--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/3rdparty/ptmalloc/malloc.c Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,5515 @@
+/*
+ $Id: malloc.c,v 1.4 2006/03/30 16:47:29 wg Exp $
+
+ This version of malloc.c was adapted for ptmalloc3 by Wolfram Gloger
+ <wg@malloc.de>. Therefore, some of the comments below do not apply
+ for this modified version. However, it is the intention to keep
+ differences to Doug Lea's original version minimal, hence the
+ comments were mostly left unchanged.
+
+ -----------------------------------------------------------------------
+
+ This is a version (aka dlmalloc) of malloc/free/realloc written by
+ Doug Lea and released to the public domain, as explained at
+ http://creativecommons.org/licenses/publicdomain. Send questions,
+ comments, complaints, performance data, etc to dl@cs.oswego.edu
+
+* Version pre-2.8.4 Wed Mar 29 19:46:29 2006 (dl at gee)
+
+ Note: There may be an updated version of this malloc obtainable at
+ ftp://gee.cs.oswego.edu/pub/misc/malloc.c
+ Check before installing!
+
+* Quickstart
+
+ This library is all in one file to simplify the most common usage:
+ ftp it, compile it (-O3), and link it into another program. All of
+ the compile-time options default to reasonable values for use on
+ most platforms. You might later want to step through various
+ compile-time and dynamic tuning options.
+
+ For convenience, an include file for code using this malloc is at:
+ ftp://gee.cs.oswego.edu/pub/misc/malloc-2.8.3.h
+ You don't really need this .h file unless you call functions not
+ defined in your system include files. The .h file contains only the
+ excerpts from this file needed for using this malloc on ANSI C/C++
+ systems, so long as you haven't changed compile-time options about
+ naming and tuning parameters. If you do, then you can create your
+ own malloc.h that does include all settings by cutting at the point
+ indicated below. Note that you may already by default be using a C
+ library containing a malloc that is based on some version of this
+ malloc (for example in linux). You might still want to use the one
+ in this file to customize settings or to avoid overheads associated
+ with library versions.
+
+* Vital statistics:
+
+ Supported pointer/size_t representation: 4 or 8 bytes
+ size_t MUST be an unsigned type of the same width as
+ pointers. (If you are using an ancient system that declares
+ size_t as a signed type, or need it to be a different width
+ than pointers, you can use a previous release of this malloc
+ (e.g. 2.7.2) supporting these.)
+
+ Alignment: 8 bytes (default)
+ This suffices for nearly all current machines and C compilers.
+ However, you can define MALLOC_ALIGNMENT to be wider than this
+ if necessary (up to 128bytes), at the expense of using more space.
+
+ Minimum overhead per allocated chunk: 4 or 8 bytes (if 4byte sizes)
+ 8 or 16 bytes (if 8byte sizes)
+ Each malloced chunk has a hidden word of overhead holding size
+ and status information, and additional cross-check word
+ if FOOTERS is defined.
+
+ Minimum allocated size: 4-byte ptrs: 16 bytes (including overhead)
+ 8-byte ptrs: 32 bytes (including overhead)
+
+ Even a request for zero bytes (i.e., malloc(0)) returns a
+ pointer to something of the minimum allocatable size.
+ The maximum overhead wastage (i.e., number of extra bytes
+ allocated than were requested in malloc) is less than or equal
+ to the minimum size, except for requests >= mmap_threshold that
+ are serviced via mmap(), where the worst case wastage is about
+ 32 bytes plus the remainder from a system page (the minimal
+ mmap unit); typically 4096 or 8192 bytes.
+
+ Security: static-safe; optionally more or less
+ The "security" of malloc refers to the ability of malicious
+ code to accentuate the effects of errors (for example, freeing
+ space that is not currently malloc'ed or overwriting past the
+ ends of chunks) in code that calls malloc. This malloc
+ guarantees not to modify any memory locations below the base of
+ heap, i.e., static variables, even in the presence of usage
+ errors. The routines additionally detect most improper frees
+ and reallocs. All this holds as long as the static bookkeeping
+ for malloc itself is not corrupted by some other means. This
+ is only one aspect of security -- these checks do not, and
+ cannot, detect all possible programming errors.
+
+ If FOOTERS is defined nonzero, then each allocated chunk
+ carries an additional check word to verify that it was malloced
+ from its space. These check words are the same within each
+ execution of a program using malloc, but differ across
+ executions, so externally crafted fake chunks cannot be
+ freed. This improves security by rejecting frees/reallocs that
+ could corrupt heap memory, in addition to the checks preventing
+ writes to statics that are always on. This may further improve
+ security at the expense of time and space overhead. (Note that
+ FOOTERS may also be worth using with MSPACES.)
+
+ By default detected errors cause the program to abort (calling
+ "abort()"). You can override this to instead proceed past
+ errors by defining PROCEED_ON_ERROR. In this case, a bad free
+ has no effect, and a malloc that encounters a bad address
+ caused by user overwrites will ignore the bad address by
+ dropping pointers and indices to all known memory. This may
+ be appropriate for programs that should continue if at all
+ possible in the face of programming errors, although they may
+ run out of memory because dropped memory is never reclaimed.
+
+ If you don't like either of these options, you can define
+ CORRUPTION_ERROR_ACTION and USAGE_ERROR_ACTION to do anything
+ else. And if if you are sure that your program using malloc has
+ no errors or vulnerabilities, you can define INSECURE to 1,
+ which might (or might not) provide a small performance improvement.
+
+ Thread-safety: NOT thread-safe unless USE_LOCKS defined
+ When USE_LOCKS is defined, each public call to malloc, free,
+ etc is surrounded with either a pthread mutex or a win32
+ spinlock (depending on WIN32). This is not especially fast, and
+ can be a major bottleneck. It is designed only to provide
+ minimal protection in concurrent environments, and to provide a
+ basis for extensions. If you are using malloc in a concurrent
+ program, consider instead using nedmalloc
+ (http://www.nedprod.com/programs/portable/nedmalloc/) or
+ ptmalloc (See http://www.malloc.de), which are derived
+ from versions of this malloc.
+
+ System requirements: Any combination of MORECORE and/or MMAP/MUNMAP
+ This malloc can use unix sbrk or any emulation (invoked using
+ the CALL_MORECORE macro) and/or mmap/munmap or any emulation
+ (invoked using CALL_MMAP/CALL_MUNMAP) to get and release system
+ memory. On most unix systems, it tends to work best if both
+ MORECORE and MMAP are enabled. On Win32, it uses emulations
+ based on VirtualAlloc. It also uses common C library functions
+ like memset.
+
+ Compliance: I believe it is compliant with the Single Unix Specification
+ (See http://www.unix.org). Also SVID/XPG, ANSI C, and probably
+ others as well.
+
+* Overview of algorithms
+
+ This is not the fastest, most space-conserving, most portable, or
+ most tunable malloc ever written. However it is among the fastest
+ while also being among the most space-conserving, portable and
+ tunable. Consistent balance across these factors results in a good
+ general-purpose allocator for malloc-intensive programs.
+
+ In most ways, this malloc is a best-fit allocator. Generally, it
+ chooses the best-fitting existing chunk for a request, with ties
+ broken in approximately least-recently-used order. (This strategy
+ normally maintains low fragmentation.) However, for requests less
+ than 256bytes, it deviates from best-fit when there is not an
+ exactly fitting available chunk by preferring to use space adjacent
+ to that used for the previous small request, as well as by breaking
+ ties in approximately most-recently-used order. (These enhance
+ locality of series of small allocations.) And for very large requests
+ (>= 256Kb by default), it relies on system memory mapping
+ facilities, if supported. (This helps avoid carrying around and
+ possibly fragmenting memory used only for large chunks.)
+
+ All operations (except malloc_stats and mallinfo) have execution
+ times that are bounded by a constant factor of the number of bits in
+ a size_t, not counting any clearing in calloc or copying in realloc,
+ or actions surrounding MORECORE and MMAP that have times
+ proportional to the number of non-contiguous regions returned by
+ system allocation routines, which is often just 1. In real-time
+ applications, you can optionally suppress segment traversals using
+ NO_SEGMENT_TRAVERSAL, which assures bounded execution even when
+ system allocators return non-contiguous spaces, at the typical
+ expense of carrying around more memory and increased fragmentation.
+
+ The implementation is not very modular and seriously overuses
+ macros. Perhaps someday all C compilers will do as good a job
+ inlining modular code as can now be done by brute-force expansion,
+ but now, enough of them seem not to.
+
+ Some compilers issue a lot of warnings about code that is
+ dead/unreachable only on some platforms, and also about intentional
+ uses of negation on unsigned types. All known cases of each can be
+ ignored.
+
+ For a longer but out of date high-level description, see
+ http://gee.cs.oswego.edu/dl/html/malloc.html
+
+* MSPACES
+ If MSPACES is defined, then in addition to malloc, free, etc.,
+ this file also defines mspace_malloc, mspace_free, etc. These
+ are versions of malloc routines that take an "mspace" argument
+ obtained using create_mspace, to control all internal bookkeeping.
+ If ONLY_MSPACES is defined, only these versions are compiled.
+ So if you would like to use this allocator for only some allocations,
+ and your system malloc for others, you can compile with
+ ONLY_MSPACES and then do something like...
+ static mspace mymspace = create_mspace(0,0); // for example
+ #define mymalloc(bytes) mspace_malloc(mymspace, bytes)
+
+ (Note: If you only need one instance of an mspace, you can instead
+ use "USE_DL_PREFIX" to relabel the global malloc.)
+
+ You can similarly create thread-local allocators by storing
+ mspaces as thread-locals. For example:
+ static __thread mspace tlms = 0;
+ void* tlmalloc(size_t bytes) {
+ if (tlms == 0) tlms = create_mspace(0, 0);
+ return mspace_malloc(tlms, bytes);
+ }
+ void tlfree(void* mem) { mspace_free(tlms, mem); }
+
+ Unless FOOTERS is defined, each mspace is completely independent.
+ You cannot allocate from one and free to another (although
+ conformance is only weakly checked, so usage errors are not always
+ caught). If FOOTERS is defined, then each chunk carries around a tag
+ indicating its originating mspace, and frees are directed to their
+ originating spaces.
+
+ ------------------------- Compile-time options ---------------------------
+
+Be careful in setting #define values for numerical constants of type
+size_t. On some systems, literal values are not automatically extended
+to size_t precision unless they are explicitly casted. You can also
+use the symbolic values MAX_SIZE_T, SIZE_T_ONE, etc below.
+
+WIN32 default: defined if _WIN32 defined
+ Defining WIN32 sets up defaults for MS environment and compilers.
+ Otherwise defaults are for unix.
+
+MALLOC_ALIGNMENT default: (size_t)8
+ Controls the minimum alignment for malloc'ed chunks. It must be a
+ power of two and at least 8, even on machines for which smaller
+ alignments would suffice. It may be defined as larger than this
+ though. Note however that code and data structures are optimized for
+ the case of 8-byte alignment.
+
+MSPACES default: 0 (false)
+ If true, compile in support for independent allocation spaces.
+ This is only supported if HAVE_MMAP is true.
+
+ONLY_MSPACES default: 0 (false)
+ If true, only compile in mspace versions, not regular versions.
+
+USE_LOCKS default: 0 (false)
+ Causes each call to each public routine to be surrounded with
+ pthread or WIN32 mutex lock/unlock. (If set true, this can be
+ overridden on a per-mspace basis for mspace versions.) If set to a
+ non-zero value other than 1, locks are used, but their
+ implementation is left out, so lock functions must be supplied manually.
+
+USE_SPIN_LOCKS default: 1 iff USE_LOCKS and on x86 using gcc or MSC
+ If true, uses custom spin locks for locking. This is currently
+ supported only for x86 platforms using gcc or recent MS compilers.
+ Otherwise, posix locks or win32 critical sections are used.
+
+FOOTERS default: 0
+ If true, provide extra checking and dispatching by placing
+ information in the footers of allocated chunks. This adds
+ space and time overhead.
+
+INSECURE default: 0
+ If true, omit checks for usage errors and heap space overwrites.
+
+USE_DL_PREFIX default: NOT defined
+ Causes compiler to prefix all public routines with the string 'dl'.
+ This can be useful when you only want to use this malloc in one part
+ of a program, using your regular system malloc elsewhere.
+
+ABORT default: defined as abort()
+ Defines how to abort on failed checks. On most systems, a failed
+ check cannot die with an "assert" or even print an informative
+ message, because the underlying print routines in turn call malloc,
+ which will fail again. Generally, the best policy is to simply call
+ abort(). It's not very useful to do more than this because many
+ errors due to overwriting will show up as address faults (null, odd
+ addresses etc) rather than malloc-triggered checks, so will also
+ abort. Also, most compilers know that abort() does not return, so
+ can better optimize code conditionally calling it.
+
+PROCEED_ON_ERROR default: defined as 0 (false)
+ Controls whether detected bad addresses cause them to bypassed
+ rather than aborting. If set, detected bad arguments to free and
+ realloc are ignored. And all bookkeeping information is zeroed out
+ upon a detected overwrite of freed heap space, thus losing the
+ ability to ever return it from malloc again, but enabling the
+ application to proceed. If PROCEED_ON_ERROR is defined, the
+ static variable malloc_corruption_error_count is compiled in
+ and can be examined to see if errors have occurred. This option
+ generates slower code than the default abort policy.
+
+DEBUG default: NOT defined
+ The DEBUG setting is mainly intended for people trying to modify
+ this code or diagnose problems when porting to new platforms.
+ However, it may also be able to better isolate user errors than just
+ using runtime checks. The assertions in the check routines spell
+ out in more detail the assumptions and invariants underlying the
+ algorithms. The checking is fairly extensive, and will slow down
+ execution noticeably. Calling malloc_stats or mallinfo with DEBUG
+ set will attempt to check every non-mmapped allocated and free chunk
+ in the course of computing the summaries.
+
+ABORT_ON_ASSERT_FAILURE default: defined as 1 (true)
+ Debugging assertion failures can be nearly impossible if your
+ version of the assert macro causes malloc to be called, which will
+ lead to a cascade of further failures, blowing the runtime stack.
+ ABORT_ON_ASSERT_FAILURE cause assertions failures to call abort(),
+ which will usually make debugging easier.
+
+MALLOC_FAILURE_ACTION default: sets errno to ENOMEM, or no-op on win32
+ The action to take before "return 0" when malloc fails to be able to
+ return memory because there is none available.
+
+HAVE_MORECORE default: 1 (true) unless win32 or ONLY_MSPACES
+ True if this system supports sbrk or an emulation of it.
+
+MORECORE default: sbrk
+ The name of the sbrk-style system routine to call to obtain more
+ memory. See below for guidance on writing custom MORECORE
+ functions. The type of the argument to sbrk/MORECORE varies across
+ systems. It cannot be size_t, because it supports negative
+ arguments, so it is normally the signed type of the same width as
+ size_t (sometimes declared as "intptr_t"). It doesn't much matter
+ though. Internally, we only call it with arguments less than half
+ the max value of a size_t, which should work across all reasonable
+ possibilities, although sometimes generating compiler warnings. See
+ near the end of this file for guidelines for creating a custom
+ version of MORECORE.
+
+MORECORE_CONTIGUOUS default: 1 (true) if HAVE_MORECORE
+ If true, take advantage of fact that consecutive calls to MORECORE
+ with positive arguments always return contiguous increasing
+ addresses. This is true of unix sbrk. It does not hurt too much to
+ set it true anyway, since malloc copes with non-contiguities.
+ Setting it false when definitely non-contiguous saves time
+ and possibly wasted space it would take to discover this though.
+
+MORECORE_CANNOT_TRIM default: NOT defined
+ True if MORECORE cannot release space back to the system when given
+ negative arguments. This is generally necessary only if you are
+ using a hand-crafted MORECORE function that cannot handle negative
+ arguments.
+
+NO_SEGMENT_TRAVERSAL default: 0
+ If non-zero, suppresses traversals of memory segments
+ returned by either MORECORE or CALL_MMAP. This disables
+ merging of segments that are contiguous, and selectively
+ releasing them to the OS if unused, but bounds execution times.
+
+HAVE_MMAP default: 1 (true)
+ True if this system supports mmap or an emulation of it. If so, and
+ HAVE_MORECORE is not true, MMAP is used for all system
+ allocation. If set and HAVE_MORECORE is true as well, MMAP is
+ primarily used to directly allocate very large blocks. It is also
+ used as a backup strategy in cases where MORECORE fails to provide
+ space from system. Note: A single call to MUNMAP is assumed to be
+ able to unmap memory that may have be allocated using multiple calls
+ to MMAP, so long as they are adjacent.
+
+HAVE_MREMAP default: 1 on linux, else 0
+ If true realloc() uses mremap() to re-allocate large blocks and
+ extend or shrink allocation spaces.
+
+MMAP_CLEARS default: 1 except on WINCE.
+ True if mmap clears memory so calloc doesn't need to. This is true
+ for standard unix mmap using /dev/zero and on WIN32 except for WINCE.
+
+USE_BUILTIN_FFS default: 0 (i.e., not used)
+ Causes malloc to use the builtin ffs() function to compute indices.
+ Some compilers may recognize and intrinsify ffs to be faster than the
+ supplied C version. Also, the case of x86 using gcc is special-cased
+ to an asm instruction, so is already as fast as it can be, and so
+ this setting has no effect. Similarly for Win32 under recent MS compilers.
+ (On most x86s, the asm version is only slightly faster than the C version.)
+
+malloc_getpagesize default: derive from system includes, or 4096.
+ The system page size. To the extent possible, this malloc manages
+ memory from the system in page-size units. This may be (and
+ usually is) a function rather than a constant. This is ignored
+ if WIN32, where page size is determined using getSystemInfo during
+ initialization.
+
+USE_DEV_RANDOM default: 0 (i.e., not used)
+ Causes malloc to use /dev/random to initialize secure magic seed for
+ stamping footers. Otherwise, the current time is used.
+
+NO_MALLINFO default: 0
+ If defined, don't compile "mallinfo". This can be a simple way
+ of dealing with mismatches between system declarations and
+ those in this file.
+
+MALLINFO_FIELD_TYPE default: size_t
+ The type of the fields in the mallinfo struct. This was originally
+ defined as "int" in SVID etc, but is more usefully defined as
+ size_t. The value is used only if HAVE_USR_INCLUDE_MALLOC_H is not set
+
+REALLOC_ZERO_BYTES_FREES default: not defined
+ This should be set if a call to realloc with zero bytes should
+ be the same as a call to free. Some people think it should. Otherwise,
+ since this malloc returns a unique pointer for malloc(0), so does
+ realloc(p, 0).
+
+LACKS_UNISTD_H, LACKS_FCNTL_H, LACKS_SYS_PARAM_H, LACKS_SYS_MMAN_H
+LACKS_STRINGS_H, LACKS_STRING_H, LACKS_SYS_TYPES_H, LACKS_ERRNO_H
+LACKS_STDLIB_H default: NOT defined unless on WIN32
+ Define these if your system does not have these header files.
+ You might need to manually insert some of the declarations they provide.
+
+DEFAULT_GRANULARITY default: page size if MORECORE_CONTIGUOUS,
+ system_info.dwAllocationGranularity in WIN32,
+ otherwise 64K.
+ Also settable using mallopt(M_GRANULARITY, x)
+ The unit for allocating and deallocating memory from the system. On
+ most systems with contiguous MORECORE, there is no reason to
+ make this more than a page. However, systems with MMAP tend to
+ either require or encourage larger granularities. You can increase
+ this value to prevent system allocation functions to be called so
+ often, especially if they are slow. The value must be at least one
+ page and must be a power of two. Setting to 0 causes initialization
+ to either page size or win32 region size. (Note: In previous
+ versions of malloc, the equivalent of this option was called
+ "TOP_PAD")
+
+DEFAULT_TRIM_THRESHOLD default: 2MB
+ Also settable using mallopt(M_TRIM_THRESHOLD, x)
+ The maximum amount of unused top-most memory to keep before
+ releasing via malloc_trim in free(). Automatic trimming is mainly
+ useful in long-lived programs using contiguous MORECORE. Because
+ trimming via sbrk can be slow on some systems, and can sometimes be
+ wasteful (in cases where programs immediately afterward allocate
+ more large chunks) the value should be high enough so that your
+ overall system performance would improve by releasing this much
+ memory. As a rough guide, you might set to a value close to the
+ average size of a process (program) running on your system.
+ Releasing this much memory would allow such a process to run in
+ memory. Generally, it is worth tuning trim thresholds when a
+ program undergoes phases where several large chunks are allocated
+ and released in ways that can reuse each other's storage, perhaps
+ mixed with phases where there are no such chunks at all. The trim
+ value must be greater than page size to have any useful effect. To
+ disable trimming completely, you can set to MAX_SIZE_T. Note that the trick
+ some people use of mallocing a huge space and then freeing it at
+ program startup, in an attempt to reserve system memory, doesn't
+ have the intended effect under automatic trimming, since that memory
+ will immediately be returned to the system.
+
+DEFAULT_MMAP_THRESHOLD default: 256K
+ Also settable using mallopt(M_MMAP_THRESHOLD, x)
+ The request size threshold for using MMAP to directly service a
+ request. Requests of at least this size that cannot be allocated
+ using already-existing space will be serviced via mmap. (If enough
+ normal freed space already exists it is used instead.) Using mmap
+ segregates relatively large chunks of memory so that they can be
+ individually obtained and released from the host system. A request
+ serviced through mmap is never reused by any other request (at least
+ not directly; the system may just so happen to remap successive
+ requests to the same locations). Segregating space in this way has
+ the benefits that: Mmapped space can always be individually released
+ back to the system, which helps keep the system level memory demands
+ of a long-lived program low. Also, mapped memory doesn't become
+ `locked' between other chunks, as can happen with normally allocated
+ chunks, which means that even trimming via malloc_trim would not
+ release them. However, it has the disadvantage that the space
+ cannot be reclaimed, consolidated, and then used to service later
+ requests, as happens with normal chunks. The advantages of mmap
+ nearly always outweigh disadvantages for "large" chunks, but the
+ value of "large" may vary across systems. The default is an
+ empirically derived value that works well in most systems. You can
+ disable mmap by setting to MAX_SIZE_T.
+
+MAX_RELEASE_CHECK_RATE default: 255 unless not HAVE_MMAP
+ The number of consolidated frees between checks to release
+ unused segments when freeing. When using non-contiguous segments,
+ especially with multiple mspaces, checking only for topmost space
+ doesn't always suffice to trigger trimming. To compensate for this,
+ free() will, with a period of MAX_RELEASE_CHECK_RATE (or the
+ current number of segments, if greater) try to release unused
+ segments to the OS when freeing chunks that result in
+ consolidation. The best value for this parameter is a compromise
+ between slowing down frees with relatively costly checks that
+ rarely trigger versus holding on to unused memory. To effectively
+ disable, set to MAX_SIZE_T. This may lead to a very slight speed
+ improvement at the expense of carrying around more memory.
+*/
+
+#ifndef WIN32
+#ifdef _WIN32
+#define WIN32 1
+#endif /* _WIN32 */
+#endif /* WIN32 */
+#ifdef WIN32
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#define HAVE_MMAP 1
+#define HAVE_MORECORE 0
+#define LACKS_UNISTD_H
+#define LACKS_SYS_PARAM_H
+#define LACKS_SYS_MMAN_H
+#define LACKS_STRING_H
+#define LACKS_STRINGS_H
+#define LACKS_SYS_TYPES_H
+#define LACKS_ERRNO_H
+#define MALLOC_FAILURE_ACTION
+#ifdef _WIN32_WCE /* WINCE reportedly does not clear */
+#define MMAP_CLEARS 0
+#else
+#define MMAP_CLEARS 1
+#endif /* _WIN32_WCE */
+#endif /* WIN32 */
+
+#if defined(DARWIN) || defined(_DARWIN)
+/* Mac OSX docs advise not to use sbrk; it seems better to use mmap */
+#ifndef HAVE_MORECORE
+#define HAVE_MORECORE 0
+#define HAVE_MMAP 1
+#endif /* HAVE_MORECORE */
+#endif /* DARWIN */
+
+#ifndef LACKS_SYS_TYPES_H
+#include <sys/types.h> /* For size_t */
+#endif /* LACKS_SYS_TYPES_H */
+
+/* The maximum possible size_t value has all bits set */
+#define MAX_SIZE_T (~(size_t)0)
+
+#ifndef ONLY_MSPACES
+#define ONLY_MSPACES 0
+#endif /* ONLY_MSPACES */
+#ifndef MSPACES
+#if ONLY_MSPACES
+#define MSPACES 1
+#else /* ONLY_MSPACES */
+#define MSPACES 0
+#endif /* ONLY_MSPACES */
+#endif /* MSPACES */
+#ifndef MALLOC_ALIGNMENT
+#define MALLOC_ALIGNMENT ((size_t)8U)
+#endif /* MALLOC_ALIGNMENT */
+#ifndef FOOTERS
+#define FOOTERS 0
+#endif /* FOOTERS */
+#ifndef ABORT
+#define ABORT abort()
+#endif /* ABORT */
+#ifndef ABORT_ON_ASSERT_FAILURE
+#define ABORT_ON_ASSERT_FAILURE 1
+#endif /* ABORT_ON_ASSERT_FAILURE */
+#ifndef PROCEED_ON_ERROR
+#define PROCEED_ON_ERROR 0
+#endif /* PROCEED_ON_ERROR */
+#ifndef USE_LOCKS
+#define USE_LOCKS 0
+#endif /* USE_LOCKS */
+#ifndef USE_SPIN_LOCKS
+#if USE_LOCKS && (defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))) || (defined(_MSC_VER) && _MSC_VER>=1310)
+#define USE_SPIN_LOCKS 1
+#else
+#define USE_SPIN_LOCKS 0
+#endif /* USE_LOCKS && ... */
+#endif /* USE_SPIN_LOCKS */
+#ifndef INSECURE
+#define INSECURE 0
+#endif /* INSECURE */
+#ifndef HAVE_MMAP
+#define HAVE_MMAP 1
+#endif /* HAVE_MMAP */
+#ifndef MMAP_CLEARS
+#define MMAP_CLEARS 1
+#endif /* MMAP_CLEARS */
+#ifndef HAVE_MREMAP
+#ifdef linux
+#define HAVE_MREMAP 1
+#else /* linux */
+#define HAVE_MREMAP 0
+#endif /* linux */
+#endif /* HAVE_MREMAP */
+#ifndef MALLOC_FAILURE_ACTION
+#define MALLOC_FAILURE_ACTION errno = ENOMEM;
+#endif /* MALLOC_FAILURE_ACTION */
+#ifndef HAVE_MORECORE
+#if ONLY_MSPACES
+#define HAVE_MORECORE 0
+#else /* ONLY_MSPACES */
+#define HAVE_MORECORE 1
+#endif /* ONLY_MSPACES */
+#endif /* HAVE_MORECORE */
+#if !HAVE_MORECORE
+#define MORECORE_CONTIGUOUS 0
+#else /* !HAVE_MORECORE */
+#ifndef MORECORE
+#define MORECORE sbrk
+#endif /* MORECORE */
+#ifndef MORECORE_CONTIGUOUS
+#define MORECORE_CONTIGUOUS 1
+#endif /* MORECORE_CONTIGUOUS */
+#endif /* HAVE_MORECORE */
+#ifndef DEFAULT_GRANULARITY
+#if MORECORE_CONTIGUOUS
+#define DEFAULT_GRANULARITY (0) /* 0 means to compute in init_mparams */
+#else /* MORECORE_CONTIGUOUS */
+#define DEFAULT_GRANULARITY ((size_t)64U * (size_t)1024U)
+#endif /* MORECORE_CONTIGUOUS */
+#endif /* DEFAULT_GRANULARITY */
+#ifndef DEFAULT_TRIM_THRESHOLD
+#ifndef MORECORE_CANNOT_TRIM
+#define DEFAULT_TRIM_THRESHOLD ((size_t)2U * (size_t)1024U * (size_t)1024U)
+#else /* MORECORE_CANNOT_TRIM */
+#define DEFAULT_TRIM_THRESHOLD MAX_SIZE_T
+#endif /* MORECORE_CANNOT_TRIM */
+#endif /* DEFAULT_TRIM_THRESHOLD */
+#ifndef DEFAULT_MMAP_THRESHOLD
+#if HAVE_MMAP
+#define DEFAULT_MMAP_THRESHOLD ((size_t)256U * (size_t)1024U)
+#else /* HAVE_MMAP */
+#define DEFAULT_MMAP_THRESHOLD MAX_SIZE_T
+#endif /* HAVE_MMAP */
+#endif /* DEFAULT_MMAP_THRESHOLD */
+#ifndef MAX_RELEASE_CHECK_RATE
+#if HAVE_MMAP
+#define MAX_RELEASE_CHECK_RATE 255
+#else
+#define MAX_RELEASE_CHECK_RATE MAX_SIZE_T
+#endif /* HAVE_MMAP */
+#endif /* MAX_RELEASE_CHECK_RATE */
+#ifndef USE_BUILTIN_FFS
+#define USE_BUILTIN_FFS 0
+#endif /* USE_BUILTIN_FFS */
+#ifndef USE_DEV_RANDOM
+#define USE_DEV_RANDOM 0
+#endif /* USE_DEV_RANDOM */
+#ifndef NO_MALLINFO
+#define NO_MALLINFO 0
+#endif /* NO_MALLINFO */
+#ifndef MALLINFO_FIELD_TYPE
+#define MALLINFO_FIELD_TYPE size_t
+#endif /* MALLINFO_FIELD_TYPE */
+#ifndef NO_SEGMENT_TRAVERSAL
+#define NO_SEGMENT_TRAVERSAL 0
+#endif /* NO_SEGMENT_TRAVERSAL */
+
+/*
+ mallopt tuning options. SVID/XPG defines four standard parameter
+ numbers for mallopt, normally defined in malloc.h. None of these
+ are used in this malloc, so setting them has no effect. But this
+ malloc does support the following options.
+*/
+
+#define M_TRIM_THRESHOLD (-1)
+#define M_GRANULARITY (-2)
+#define M_MMAP_THRESHOLD (-3)
+
+/* ------------------------ Mallinfo declarations ------------------------ */
+
+#if !NO_MALLINFO
+/*
+ This version of malloc supports the standard SVID/XPG mallinfo
+ routine that returns a struct containing usage properties and
+ statistics. It should work on any system that has a
+ /usr/include/malloc.h defining struct mallinfo. The main
+ declaration needed is the mallinfo struct that is returned (by-copy)
+ by mallinfo(). The malloinfo struct contains a bunch of fields that
+ are not even meaningful in this version of malloc. These fields are
+ are instead filled by mallinfo() with other numbers that might be of
+ interest.
+
+ HAVE_USR_INCLUDE_MALLOC_H should be set if you have a
+ /usr/include/malloc.h file that includes a declaration of struct
+ mallinfo. If so, it is included; else a compliant version is
+ declared below. These must be precisely the same for mallinfo() to
+ work. The original SVID version of this struct, defined on most
+ systems with mallinfo, declares all fields as ints. But some others
+ define as unsigned long. If your system defines the fields using a
+ type of different width than listed here, you MUST #include your
+ system version and #define HAVE_USR_INCLUDE_MALLOC_H.
+*/
+
+/* #define HAVE_USR_INCLUDE_MALLOC_H */
+
+#ifdef HAVE_USR_INCLUDE_MALLOC_H
+#include "/usr/include/malloc.h"
+#else /* HAVE_USR_INCLUDE_MALLOC_H */
+
+struct mallinfo {
+ MALLINFO_FIELD_TYPE arena; /* non-mmapped space allocated from system */
+ MALLINFO_FIELD_TYPE ordblks; /* number of free chunks */
+ MALLINFO_FIELD_TYPE smblks; /* always 0 */
+ MALLINFO_FIELD_TYPE hblks; /* always 0 */
+ MALLINFO_FIELD_TYPE hblkhd; /* space in mmapped regions */
+ MALLINFO_FIELD_TYPE usmblks; /* maximum total allocated space */
+ MALLINFO_FIELD_TYPE fsmblks; /* always 0 */
+ MALLINFO_FIELD_TYPE uordblks; /* total allocated space */
+ MALLINFO_FIELD_TYPE fordblks; /* total free space */
+ MALLINFO_FIELD_TYPE keepcost; /* releasable (via malloc_trim) space */
+};
+
+#endif /* HAVE_USR_INCLUDE_MALLOC_H */
+#endif /* NO_MALLINFO */
+
+/*
+ Try to persuade compilers to inline. The most critical functions for
+ inlining are defined as macros, so these aren't used for them.
+*/
+
+#ifndef FORCEINLINE
+ #if defined(__GNUC__)
+#define FORCEINLINE __inline __attribute__ ((always_inline))
+ #elif defined(_MSC_VER)
+ #define FORCEINLINE __forceinline
+ #endif
+#endif
+#ifndef NOINLINE
+ #if defined(__GNUC__)
+ #define NOINLINE __attribute__ ((noinline))
+ #elif defined(_MSC_VER)
+ #define NOINLINE __declspec(noinline)
+ #else
+ #define NOINLINE
+ #endif
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#ifndef FORCEINLINE
+ #define FORCEINLINE inline
+#endif
+#endif /* __cplusplus */
+#ifndef FORCEINLINE
+ #define FORCEINLINE
+#endif
+
+#if !ONLY_MSPACES
+
+/* ------------------- Declarations of public routines ------------------- */
+
+#ifndef USE_DL_PREFIX
+#define dlcalloc calloc
+#define dlfree free
+#define dlmalloc malloc
+#define dlmemalign memalign
+#define dlrealloc realloc
+#define dlvalloc valloc
+#define dlpvalloc pvalloc
+#define dlmallinfo mallinfo
+#define dlmallopt mallopt
+#define dlmalloc_trim malloc_trim
+#define dlmalloc_stats malloc_stats
+#define dlmalloc_usable_size malloc_usable_size
+#define dlmalloc_footprint malloc_footprint
+#define dlmalloc_max_footprint malloc_max_footprint
+#define dlindependent_calloc independent_calloc
+#define dlindependent_comalloc independent_comalloc
+#endif /* USE_DL_PREFIX */
+
+
+/*
+ malloc(size_t n)
+ Returns a pointer to a newly allocated chunk of at least n bytes, or
+ null if no space is available, in which case errno is set to ENOMEM
+ on ANSI C systems.
+
+ If n is zero, malloc returns a minimum-sized chunk. (The minimum
+ size is 16 bytes on most 32bit systems, and 32 bytes on 64bit
+ systems.) Note that size_t is an unsigned type, so calls with
+ arguments that would be negative if signed are interpreted as
+ requests for huge amounts of space, which will often fail. The
+ maximum supported value of n differs across systems, but is in all
+ cases less than the maximum representable value of a size_t.
+*/
+void* dlmalloc(size_t);
+
+/*
+ free(void* p)
+ Releases the chunk of memory pointed to by p, that had been previously
+ allocated using malloc or a related routine such as realloc.
+ It has no effect if p is null. If p was not malloced or already
+ freed, free(p) will by default cause the current program to abort.
+*/
+void dlfree(void*);
+
+/*
+ calloc(size_t n_elements, size_t element_size);
+ Returns a pointer to n_elements * element_size bytes, with all locations
+ set to zero.
+*/
+void* dlcalloc(size_t, size_t);
+
+/*
+ realloc(void* p, size_t n)
+ Returns a pointer to a chunk of size n that contains the same data
+ as does chunk p up to the minimum of (n, p's size) bytes, or null
+ if no space is available.
+
+ The returned pointer may or may not be the same as p. The algorithm
+ prefers extending p in most cases when possible, otherwise it
+ employs the equivalent of a malloc-copy-free sequence.
+
+ If p is null, realloc is equivalent to malloc.
+
+ If space is not available, realloc returns null, errno is set (if on
+ ANSI) and p is NOT freed.
+
+ if n is for fewer bytes than already held by p, the newly unused
+ space is lopped off and freed if possible. realloc with a size
+ argument of zero (re)allocates a minimum-sized chunk.
+
+ The old unix realloc convention of allowing the last-free'd chunk
+ to be used as an argument to realloc is not supported.
+*/
+
+void* dlrealloc(void*, size_t);
+
+/*
+ memalign(size_t alignment, size_t n);
+ Returns a pointer to a newly allocated chunk of n bytes, aligned
+ in accord with the alignment argument.
+
+ The alignment argument should be a power of two. If the argument is
+ not a power of two, the nearest greater power is used.
+ 8-byte alignment is guaranteed by normal malloc calls, so don't
+ bother calling memalign with an argument of 8 or less.
+
+ Overreliance on memalign is a sure way to fragment space.
+*/
+void* dlmemalign(size_t, size_t);
+
+/*
+ valloc(size_t n);
+ Equivalent to memalign(pagesize, n), where pagesize is the page
+ size of the system. If the pagesize is unknown, 4096 is used.
+*/
+void* dlvalloc(size_t);
+
+/*
+ mallopt(int parameter_number, int parameter_value)
+ Sets tunable parameters The format is to provide a
+ (parameter-number, parameter-value) pair. mallopt then sets the
+ corresponding parameter to the argument value if it can (i.e., so
+ long as the value is meaningful), and returns 1 if successful else
+ 0. SVID/XPG/ANSI defines four standard param numbers for mallopt,
+ normally defined in malloc.h. None of these are use in this malloc,
+ so setting them has no effect. But this malloc also supports other
+ options in mallopt. See below for details. Briefly, supported
+ parameters are as follows (listed defaults are for "typical"
+ configurations).
+
+ Symbol param # default allowed param values
+ M_TRIM_THRESHOLD -1 2*1024*1024 any (MAX_SIZE_T disables)
+ M_GRANULARITY -2 page size any power of 2 >= page size
+ M_MMAP_THRESHOLD -3 256*1024 any (or 0 if no MMAP support)
+*/
+int dlmallopt(int, int);
+
+/*
+ malloc_footprint();
+ Returns the number of bytes obtained from the system. The total
+ number of bytes allocated by malloc, realloc etc., is less than this
+ value. Unlike mallinfo, this function returns only a precomputed
+ result, so can be called frequently to monitor memory consumption.
+ Even if locks are otherwise defined, this function does not use them,
+ so results might not be up to date.
+*/
+size_t dlmalloc_footprint(void);
+
+/*
+ malloc_max_footprint();
+ Returns the maximum number of bytes obtained from the system. This
+ value will be greater than current footprint if deallocated space
+ has been reclaimed by the system. The peak number of bytes allocated
+ by malloc, realloc etc., is less than this value. Unlike mallinfo,
+ this function returns only a precomputed result, so can be called
+ frequently to monitor memory consumption. Even if locks are
+ otherwise defined, this function does not use them, so results might
+ not be up to date.
+*/
+size_t dlmalloc_max_footprint(void);
+
+#if !NO_MALLINFO
+/*
+ mallinfo()
+ Returns (by copy) a struct containing various summary statistics:
+
+ arena: current total non-mmapped bytes allocated from system
+ ordblks: the number of free chunks
+ smblks: always zero.
+ hblks: current number of mmapped regions
+ hblkhd: total bytes held in mmapped regions
+ usmblks: the maximum total allocated space. This will be greater
+ than current total if trimming has occurred.
+ fsmblks: always zero
+ uordblks: current total allocated space (normal or mmapped)
+ fordblks: total free space
+ keepcost: the maximum number of bytes that could ideally be released
+ back to system via malloc_trim. ("ideally" means that
+ it ignores page restrictions etc.)
+
+ Because these fields are ints, but internal bookkeeping may
+ be kept as longs, the reported values may wrap around zero and
+ thus be inaccurate.
+*/
+struct mallinfo dlmallinfo(void);
+#endif /* NO_MALLINFO */
+
+/*
+ independent_calloc(size_t n_elements, size_t element_size, void* chunks[]);
+
+ independent_calloc is similar to calloc, but instead of returning a
+ single cleared space, it returns an array of pointers to n_elements
+ independent elements that can hold contents of size elem_size, each
+ of which starts out cleared, and can be independently freed,
+ realloc'ed etc. The elements are guaranteed to be adjacently
+ allocated (this is not guaranteed to occur with multiple callocs or
+ mallocs), which may also improve cache locality in some
+ applications.
+
+ The "chunks" argument is optional (i.e., may be null, which is
+ probably the most typical usage). If it is null, the returned array
+ is itself dynamically allocated and should also be freed when it is
+ no longer needed. Otherwise, the chunks array must be of at least
+ n_elements in length. It is filled in with the pointers to the
+ chunks.
+
+ In either case, independent_calloc returns this pointer array, or
+ null if the allocation failed. If n_elements is zero and "chunks"
+ is null, it returns a chunk representing an array with zero elements
+ (which should be freed if not wanted).
+
+ Each element must be individually freed when it is no longer
+ needed. If you'd like to instead be able to free all at once, you
+ should instead use regular calloc and assign pointers into this
+ space to represent elements. (In this case though, you cannot
+ independently free elements.)
+
+ independent_calloc simplifies and speeds up implementations of many
+ kinds of pools. It may also be useful when constructing large data
+ structures that initially have a fixed number of fixed-sized nodes,
+ but the number is not known at compile time, and some of the nodes
+ may later need to be freed. For example:
+
+ struct Node { int item; struct Node* next; };
+
+ struct Node* build_list() {
+ struct Node** pool;
+ int n = read_number_of_nodes_needed();
+ if (n <= 0) return 0;
+ pool = (struct Node**)(independent_calloc(n, sizeof(struct Node), 0);
+ if (pool == 0) die();
+ // organize into a linked list...
+ struct Node* first = pool[0];
+ for (i = 0; i < n-1; ++i)
+ pool[i]->next = pool[i+1];
+ free(pool); // Can now free the array (or not, if it is needed later)
+ return first;
+ }
+*/
+void** dlindependent_calloc(size_t, size_t, void**);
+
+/*
+ independent_comalloc(size_t n_elements, size_t sizes[], void* chunks[]);
+
+ independent_comalloc allocates, all at once, a set of n_elements
+ chunks with sizes indicated in the "sizes" array. It returns
+ an array of pointers to these elements, each of which can be
+ independently freed, realloc'ed etc. The elements are guaranteed to
+ be adjacently allocated (this is not guaranteed to occur with
+ multiple callocs or mallocs), which may also improve cache locality
+ in some applications.
+
+ The "chunks" argument is optional (i.e., may be null). If it is null
+ the returned array is itself dynamically allocated and should also
+ be freed when it is no longer needed. Otherwise, the chunks array
+ must be of at least n_elements in length. It is filled in with the
+ pointers to the chunks.
+
+ In either case, independent_comalloc returns this pointer array, or
+ null if the allocation failed. If n_elements is zero and chunks is
+ null, it returns a chunk representing an array with zero elements
+ (which should be freed if not wanted).
+
+ Each element must be individually freed when it is no longer
+ needed. If you'd like to instead be able to free all at once, you
+ should instead use a single regular malloc, and assign pointers at
+ particular offsets in the aggregate space. (In this case though, you
+ cannot independently free elements.)
+
+ independent_comallac differs from independent_calloc in that each
+ element may have a different size, and also that it does not
+ automatically clear elements.
+
+ independent_comalloc can be used to speed up allocation in cases
+ where several structs or objects must always be allocated at the
+ same time. For example:
+
+ struct Head { ... }
+ struct Foot { ... }
+
+ void send_message(char* msg) {
+ int msglen = strlen(msg);
+ size_t sizes[3] = { sizeof(struct Head), msglen, sizeof(struct Foot) };
+ void* chunks[3];
+ if (independent_comalloc(3, sizes, chunks) == 0)
+ die();
+ struct Head* head = (struct Head*)(chunks[0]);
+ char* body = (char*)(chunks[1]);
+ struct Foot* foot = (struct Foot*)(chunks[2]);
+ // ...
+ }
+
+ In general though, independent_comalloc is worth using only for
+ larger values of n_elements. For small values, you probably won't
+ detect enough difference from series of malloc calls to bother.
+
+ Overuse of independent_comalloc can increase overall memory usage,
+ since it cannot reuse existing noncontiguous small chunks that
+ might be available for some of the elements.
+*/
+void** dlindependent_comalloc(size_t, size_t*, void**);
+
+
+/*
+ pvalloc(size_t n);
+ Equivalent to valloc(minimum-page-that-holds(n)), that is,
+ round up n to nearest pagesize.
+ */
+void* dlpvalloc(size_t);
+
+/*
+ malloc_trim(size_t pad);
+
+ If possible, gives memory back to the system (via negative arguments
+ to sbrk) if there is unused memory at the `high' end of the malloc
+ pool or in unused MMAP segments. You can call this after freeing
+ large blocks of memory to potentially reduce the system-level memory
+ requirements of a program. However, it cannot guarantee to reduce
+ memory. Under some allocation patterns, some large free blocks of
+ memory will be locked between two used chunks, so they cannot be
+ given back to the system.
+
+ The `pad' argument to malloc_trim represents the amount of free
+ trailing space to leave untrimmed. If this argument is zero, only
+ the minimum amount of memory to maintain internal data structures
+ will be left. Non-zero arguments can be supplied to maintain enough
+ trailing space to service future expected allocations without having
+ to re-obtain memory from the system.
+
+ Malloc_trim returns 1 if it actually released any memory, else 0.
+*/
+int dlmalloc_trim(size_t);
+
+/*
+ malloc_usable_size(void* p);
+
+ Returns the number of bytes you can actually use in
+ an allocated chunk, which may be more than you requested (although
+ often not) due to alignment and minimum size constraints.
+ You can use this many bytes without worrying about
+ overwriting other allocated objects. This is not a particularly great
+ programming practice. malloc_usable_size can be more useful in
+ debugging and assertions, for example:
+
+ p = malloc(n);
+ assert(malloc_usable_size(p) >= 256);
+*/
+size_t dlmalloc_usable_size(void*);
+
+/*
+ malloc_stats();
+ Prints on stderr the amount of space obtained from the system (both
+ via sbrk and mmap), the maximum amount (which may be more than
+ current if malloc_trim and/or munmap got called), and the current
+ number of bytes allocated via malloc (or realloc, etc) but not yet
+ freed. Note that this is the number of bytes allocated, not the
+ number requested. It will be larger than the number requested
+ because of alignment and bookkeeping overhead. Because it includes
+ alignment wastage as being in use, this figure may be greater than
+ zero even when no user-level chunks are allocated.
+
+ The reported current and maximum system memory can be inaccurate if
+ a program makes other calls to system memory allocation functions
+ (normally sbrk) outside of malloc.
+
+ malloc_stats prints only the most commonly interesting statistics.
+ More information can be obtained by calling mallinfo.
+*/
+void dlmalloc_stats(void);
+
+#endif /* ONLY_MSPACES */
+
+#if MSPACES
+
+/*
+ mspace is an opaque type representing an independent
+ region of space that supports mspace_malloc, etc.
+*/
+typedef void* mspace;
+
+/*
+ create_mspace creates and returns a new independent space with the
+ given initial capacity, or, if 0, the default granularity size. It
+ returns null if there is no system memory available to create the
+ space. If argument locked is non-zero, the space uses a separate
+ lock to control access. The capacity of the space will grow
+ dynamically as needed to service mspace_malloc requests. You can
+ control the sizes of incremental increases of this space by
+ compiling with a different DEFAULT_GRANULARITY or dynamically
+ setting with mallopt(M_GRANULARITY, value).
+*/
+mspace create_mspace(size_t capacity, int locked);
+
+/*
+ destroy_mspace destroys the given space, and attempts to return all
+ of its memory back to the system, returning the total number of
+ bytes freed. After destruction, the results of access to all memory
+ used by the space become undefined.
+*/
+size_t destroy_mspace(mspace msp);
+
+/*
+ create_mspace_with_base uses the memory supplied as the initial base
+ of a new mspace. Part (less than 128*sizeof(size_t) bytes) of this
+ space is used for bookkeeping, so the capacity must be at least this
+ large. (Otherwise 0 is returned.) When this initial space is
+ exhausted, additional memory will be obtained from the system.
+ Destroying this space will deallocate all additionally allocated
+ space (if possible) but not the initial base.
+*/
+mspace create_mspace_with_base(void* base, size_t capacity, int locked);
+
+/*
+ mspace_malloc behaves as malloc, but operates within
+ the given space.
+*/
+void* mspace_malloc(mspace msp, size_t bytes);
+
+/*
+ mspace_free behaves as free, but operates within
+ the given space.
+
+ If compiled with FOOTERS==1, mspace_free is not actually needed.
+ free may be called instead of mspace_free because freed chunks from
+ any space are handled by their originating spaces.
+*/
+void mspace_free(mspace msp, void* mem);
+
+/*
+ mspace_realloc behaves as realloc, but operates within
+ the given space.
+
+ If compiled with FOOTERS==1, mspace_realloc is not actually
+ needed. realloc may be called instead of mspace_realloc because
+ realloced chunks from any space are handled by their originating
+ spaces.
+*/
+void* mspace_realloc(mspace msp, void* mem, size_t newsize);
+
+/*
+ mspace_calloc behaves as calloc, but operates within
+ the given space.
+*/
+void* mspace_calloc(mspace msp, size_t n_elements, size_t elem_size);
+
+/*
+ mspace_memalign behaves as memalign, but operates within
+ the given space.
+*/
+void* mspace_memalign(mspace msp, size_t alignment, size_t bytes);
+
+/*
+ mspace_independent_calloc behaves as independent_calloc, but
+ operates within the given space.
+*/
+void** mspace_independent_calloc(mspace msp, size_t n_elements,
+ size_t elem_size, void* chunks[]);
+
+/*
+ mspace_independent_comalloc behaves as independent_comalloc, but
+ operates within the given space.
+*/
+void** mspace_independent_comalloc(mspace msp, size_t n_elements,
+ size_t sizes[], void* chunks[]);
+
+/*
+ mspace_footprint() returns the number of bytes obtained from the
+ system for this space.
+*/
+size_t mspace_footprint(mspace msp);
+
+/*
+ mspace_max_footprint() returns the peak number of bytes obtained from the
+ system for this space.
+*/
+size_t mspace_max_footprint(mspace msp);
+
+
+#if !NO_MALLINFO
+/*
+ mspace_mallinfo behaves as mallinfo, but reports properties of
+ the given space.
+*/
+struct mallinfo mspace_mallinfo(mspace msp);
+#endif /* NO_MALLINFO */
+
+/*
+ mspace_malloc_stats behaves as malloc_stats, but reports
+ properties of the given space.
+*/
+void mspace_malloc_stats(mspace msp);
+
+/*
+ mspace_trim behaves as malloc_trim, but
+ operates within the given space.
+*/
+int mspace_trim(mspace msp, size_t pad);
+
+/*
+ An alias for mallopt.
+*/
+int mspace_mallopt(int, int);
+
+#endif /* MSPACES */
+
+#ifdef __cplusplus
+}; /* end of extern "C" */
+#endif /* __cplusplus */
+
+/*
+ ========================================================================
+ To make a fully customizable malloc.h header file, cut everything
+ above this line, put into file malloc.h, edit to suit, and #include it
+ on the next line, as well as in programs that use this malloc.
+ ========================================================================
+*/
+
+/* #include "malloc.h" */
+
+/*------------------------------ internal #includes ---------------------- */
+
+#ifdef WIN32
+#pragma warning( disable : 4146 ) /* no "unsigned" warnings */
+#endif /* WIN32 */
+
+#include <stdio.h> /* for printing in malloc_stats */
+
+#ifndef LACKS_ERRNO_H
+#include <errno.h> /* for MALLOC_FAILURE_ACTION */
+#endif /* LACKS_ERRNO_H */
+#if FOOTERS
+#include <time.h> /* for magic initialization */
+#endif /* FOOTERS */
+#ifndef LACKS_STDLIB_H
+#include <stdlib.h> /* for abort() */
+#endif /* LACKS_STDLIB_H */
+#ifdef DEBUG
+#if ABORT_ON_ASSERT_FAILURE
+#define assert(x) if(!(x)) ABORT
+#else /* ABORT_ON_ASSERT_FAILURE */
+#include <assert.h>
+#endif /* ABORT_ON_ASSERT_FAILURE */
+#else /* DEBUG */
+#define assert(x)
+#endif /* DEBUG */
+#ifndef LACKS_STRING_H
+#include <string.h> /* for memset etc */
+#endif /* LACKS_STRING_H */
+#if USE_BUILTIN_FFS
+#ifndef LACKS_STRINGS_H
+#include <strings.h> /* for ffs */
+#endif /* LACKS_STRINGS_H */
+#endif /* USE_BUILTIN_FFS */
+#if HAVE_MMAP
+#ifndef LACKS_SYS_MMAN_H
+#include <sys/mman.h> /* for mmap */
+#endif /* LACKS_SYS_MMAN_H */
+#ifndef LACKS_FCNTL_H
+#include <fcntl.h>
+#endif /* LACKS_FCNTL_H */
+#endif /* HAVE_MMAP */
+#if HAVE_MORECORE
+#ifndef LACKS_UNISTD_H
+#include <unistd.h> /* for sbrk */
+#else /* LACKS_UNISTD_H */
+#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
+extern void* sbrk(ptrdiff_t);
+#endif /* FreeBSD etc */
+#endif /* LACKS_UNISTD_H */
+#endif /* HAVE_MMAP */
+
+/* Declarations for locking */
+#if USE_LOCKS
+#ifndef WIN32
+#include <pthread.h>
+#if defined (__SVR4) && defined (__sun) /* solaris */
+#include <thread.h>
+#endif /* solaris */
+#else
+#ifndef _M_AMD64
+/* These are already defined on AMD64 builds */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+LONG __cdecl _InterlockedCompareExchange(LPLONG volatile Dest, LONG Exchange, LONG Comp);
+LONG __cdecl _InterlockedExchange(LPLONG volatile Target, LONG Value);
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+#endif /* _M_AMD64 */
+#pragma intrinsic (_InterlockedCompareExchange)
+#pragma intrinsic (_InterlockedExchange)
+#define interlockedcompareexchange _InterlockedCompareExchange
+#define interlockedexchange _InterlockedExchange
+#endif /* Win32 */
+#endif /* USE_LOCKS */
+
+/* Declarations for bit scanning on win32 */
+#if defined(_MSC_VER) && _MSC_VER>=1300
+#ifndef BitScanForward /* Try to avoid pulling in WinNT.h */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+unsigned char _BitScanForward(unsigned long *index, unsigned long mask);
+unsigned char _BitScanReverse(unsigned long *index, unsigned long mask);
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#define BitScanForward _BitScanForward
+#define BitScanReverse _BitScanReverse
+#pragma intrinsic(_BitScanForward)
+#pragma intrinsic(_BitScanReverse)
+#endif /* BitScanForward */
+#endif /* defined(_MSC_VER) && _MSC_VER>=1300 */
+
+#ifndef WIN32
+#ifndef malloc_getpagesize
+# ifdef _SC_PAGESIZE /* some SVR4 systems omit an underscore */
+# ifndef _SC_PAGE_SIZE
+# define _SC_PAGE_SIZE _SC_PAGESIZE
+# endif
+# endif
+# ifdef _SC_PAGE_SIZE
+# define malloc_getpagesize sysconf(_SC_PAGE_SIZE)
+# else
+# if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE)
+ extern size_t getpagesize();
+# define malloc_getpagesize getpagesize()
+# else
+# ifdef WIN32 /* use supplied emulation of getpagesize */
+# define malloc_getpagesize getpagesize()
+# else
+# ifndef LACKS_SYS_PARAM_H
+# include <sys/param.h>
+# endif
+# ifdef EXEC_PAGESIZE
+# define malloc_getpagesize EXEC_PAGESIZE
+# else
+# ifdef NBPG
+# ifndef CLSIZE
+# define malloc_getpagesize NBPG
+# else
+# define malloc_getpagesize (NBPG * CLSIZE)
+# endif
+# else
+# ifdef NBPC
+# define malloc_getpagesize NBPC
+# else
+# ifdef PAGESIZE
+# define malloc_getpagesize PAGESIZE
+# else /* just guess */
+# define malloc_getpagesize ((size_t)4096U)
+# endif
+# endif
+# endif
+# endif
+# endif
+# endif
+# endif
+#endif
+#endif
+
+
+
+/* ------------------- size_t and alignment properties -------------------- */
+
+/* The byte and bit size of a size_t */
+#define SIZE_T_SIZE (sizeof(size_t))
+#define SIZE_T_BITSIZE (sizeof(size_t) << 3)
+
+/* Some constants coerced to size_t */
+/* Annoying but necessary to avoid errors on some platforms */
+#define SIZE_T_ZERO ((size_t)0)
+#define SIZE_T_ONE ((size_t)1)
+#define SIZE_T_TWO ((size_t)2)
+#define SIZE_T_FOUR ((size_t)4)
+#define TWO_SIZE_T_SIZES (SIZE_T_SIZE<<1)
+#define FOUR_SIZE_T_SIZES (SIZE_T_SIZE<<2)
+#define SIX_SIZE_T_SIZES (FOUR_SIZE_T_SIZES+TWO_SIZE_T_SIZES)
+#define HALF_MAX_SIZE_T (MAX_SIZE_T / 2U)
+
+/* The bit mask value corresponding to MALLOC_ALIGNMENT */
+#define CHUNK_ALIGN_MASK (MALLOC_ALIGNMENT - SIZE_T_ONE)
+
+/* True if address a has acceptable alignment */
+#define is_aligned(A) (((size_t)((A)) & (CHUNK_ALIGN_MASK)) == 0)
+
+/* the number of bytes to offset an address to align it */
+#define align_offset(A)\
+ ((((size_t)(A) & CHUNK_ALIGN_MASK) == 0)? 0 :\
+ ((MALLOC_ALIGNMENT - ((size_t)(A) & CHUNK_ALIGN_MASK)) & CHUNK_ALIGN_MASK))
+
+/* -------------------------- MMAP preliminaries ------------------------- */
+
+/*
+ If HAVE_MORECORE or HAVE_MMAP are false, we just define calls and
+ checks to fail so compiler optimizer can delete code rather than
+ using so many "#if"s.
+*/
+
+
+/* MORECORE and MMAP must return MFAIL on failure */
+#define MFAIL ((void*)(MAX_SIZE_T))
+#define CMFAIL ((char*)(MFAIL)) /* defined for convenience */
+
+#if !HAVE_MMAP
+#define IS_MMAPPED_BIT (SIZE_T_ZERO)
+#define USE_MMAP_BIT (SIZE_T_ZERO)
+#define CALL_MMAP(s) MFAIL
+#define CALL_MUNMAP(a, s) (-1)
+#define DIRECT_MMAP(s) MFAIL
+
+#else /* HAVE_MMAP */
+#define IS_MMAPPED_BIT (SIZE_T_ONE)
+#define USE_MMAP_BIT (SIZE_T_ONE)
+
+#ifndef WIN32
+#define CALL_MUNMAP(a, s) munmap((a), (s))
+#define MMAP_PROT (PROT_READ|PROT_WRITE)
+#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
+#define MAP_ANONYMOUS MAP_ANON
+#endif /* MAP_ANON */
+#ifdef MAP_ANONYMOUS
+#define MMAP_FLAGS (MAP_PRIVATE|MAP_ANONYMOUS)
+#define CALL_MMAP(s) mmap(0, (s), MMAP_PROT, MMAP_FLAGS, -1, 0)
+#else /* MAP_ANONYMOUS */
+/*
+ Nearly all versions of mmap support MAP_ANONYMOUS, so the following
+ is unlikely to be needed, but is supplied just in case.
+*/
+#define MMAP_FLAGS (MAP_PRIVATE)
+static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */
+#define CALL_MMAP(s) ((dev_zero_fd < 0) ? \
+ (dev_zero_fd = open("/dev/zero", O_RDWR), \
+ mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0)) : \
+ mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0))
+#endif /* MAP_ANONYMOUS */
+
+#define DIRECT_MMAP(s) CALL_MMAP(s)
+#else /* WIN32 */
+
+/* Win32 MMAP via VirtualAlloc */
+static FORCEINLINE void* win32mmap(size_t size) {
+ void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);
+ return (ptr != 0)? ptr: MFAIL;
+}
+
+/* For direct MMAP, use MEM_TOP_DOWN to minimize interference */
+static FORCEINLINE void* win32direct_mmap(size_t size) {
+ void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT|MEM_TOP_DOWN,
+ PAGE_READWRITE);
+ return (ptr != 0)? ptr: MFAIL;
+}
+
+/* This function supports releasing coalesed segments */
+static FORCEINLINE int win32munmap(void* ptr, size_t size) {
+ MEMORY_BASIC_INFORMATION minfo;
+ char* cptr = (char*)ptr;
+ while (size) {
+ if (VirtualQuery(cptr, &minfo, sizeof(minfo)) == 0)
+ return -1;
+ if (minfo.BaseAddress != cptr || minfo.AllocationBase != cptr ||
+ minfo.State != MEM_COMMIT || minfo.RegionSize > size)
+ return -1;
+ if (VirtualFree(cptr, 0, MEM_RELEASE) == 0)
+ return -1;
+ cptr += minfo.RegionSize;
+ size -= minfo.RegionSize;
+ }
+ return 0;
+}
+
+#define CALL_MMAP(s) win32mmap(s)
+#define CALL_MUNMAP(a, s) win32munmap((a), (s))
+#define DIRECT_MMAP(s) win32direct_mmap(s)
+#endif /* WIN32 */
+#endif /* HAVE_MMAP */
+
+#if HAVE_MMAP && HAVE_MREMAP
+#define CALL_MREMAP(addr, osz, nsz, mv) mremap((addr), (osz), (nsz), (mv))
+#else /* HAVE_MMAP && HAVE_MREMAP */
+#define CALL_MREMAP(addr, osz, nsz, mv) ((void)(addr),(void)(osz), \
+ (void)(nsz), (void)(mv),MFAIL)
+#endif /* HAVE_MMAP && HAVE_MREMAP */
+
+#if HAVE_MORECORE
+#define CALL_MORECORE(S) MORECORE(S)
+#else /* HAVE_MORECORE */
+#define CALL_MORECORE(S) MFAIL
+#endif /* HAVE_MORECORE */
+
+/* mstate bit set if continguous morecore disabled or failed */
+#define USE_NONCONTIGUOUS_BIT (4U)
+
+/* segment bit set in create_mspace_with_base */
+#define EXTERN_BIT (8U)
+
+
+/* --------------------------- Lock preliminaries ------------------------ */
+
+/*
+ When locks are defined, there are up to two global locks:
+
+ * If HAVE_MORECORE, morecore_mutex protects sequences of calls to
+ MORECORE. In many cases sys_alloc requires two calls, that should
+ not be interleaved with calls by other threads. This does not
+ protect against direct calls to MORECORE by other threads not
+ using this lock, so there is still code to cope the best we can on
+ interference.
+
+ * magic_init_mutex ensures that mparams.magic and other
+ unique mparams values are initialized only once.
+
+ To enable use in layered extensions, locks are reentrant.
+
+ Because lock-protected regions generally have bounded times, we use
+ the supplied simple spinlocks in the custom versions for x86.
+
+ If USE_LOCKS is > 1, the definitions of lock routines here are
+ bypassed, in which case you will need to define at least
+ INITIAL_LOCK, ACQUIRE_LOCK, RELEASE_LOCK, and
+ NULL_LOCK_INITIALIZER, and possibly TRY_LOCK and IS_LOCKED
+ (The latter two are not used in this malloc, but are
+ commonly needed in extensions.)
+*/
+
+#if USE_LOCKS == 1
+
+#if USE_SPIN_LOCKS
+#ifndef WIN32
+/* Custom pthread-style spin locks on x86 and x64 for gcc */
+struct pthread_mlock_t
+{
+ volatile pthread_t threadid;
+ volatile unsigned int c;
+ volatile unsigned int l;
+};
+#define MLOCK_T struct pthread_mlock_t
+#define CURRENT_THREAD pthread_self()
+#define SPINS_PER_YIELD 63
+static FORCEINLINE int pthread_acquire_lock (MLOCK_T *sl) {
+ if(CURRENT_THREAD==sl->threadid)
+ ++sl->c;
+ else {
+ int spins = 0;
+ for (;;) {
+ int ret;
+ __asm__ __volatile__ ("lock cmpxchgl %2,(%1)" : "=a" (ret) : "r" (&sl->l), "r" (1), "a" (0));
+ if(!ret) {
+ assert(!sl->threadid);
+ sl->threadid=CURRENT_THREAD;
+ sl->c=1;
+ break;
+ }
+ if ((++spins & SPINS_PER_YIELD) == 0) {
+#if defined (__SVR4) && defined (__sun) /* solaris */
+ thr_yield();
+#else
+#ifdef linux
+ sched_yield();
+#else /* no-op yield on unknown systems */
+ ;
+#endif /* linux */
+#endif /* solaris */
+ }
+ }
+ }
+
+ return 0;
+}
+
+static FORCEINLINE void pthread_release_lock (MLOCK_T *sl) {
+ int ret;
+ assert(CURRENT_THREAD==sl->threadid);
+ if (!--sl->c) {
+ sl->threadid=0;
+ __asm__ __volatile__ ("xchgl %2,(%1)" : "=r" (ret) : "r" (&sl->l), "0" (0));
+ }
+}
+
+static FORCEINLINE int pthread_try_lock (MLOCK_T *sl) {
+ int ret;
+ __asm__ __volatile__ ("lock cmpxchgl %2,(%1)" : "=a" (ret) : "r" (&sl->l), "r" (1), "a" (0));
+ if(!ret){
+ assert(!sl->threadid);
+ sl->threadid=CURRENT_THREAD;
+ sl->c=1;
+ return 1;
+ }
+ return 0;
+}
+
+#define INITIAL_LOCK(sl) (memset((sl), 0, sizeof(MLOCK_T)), 0)
+#define ACQUIRE_LOCK(sl) pthread_acquire_lock(sl)
+#define RELEASE_LOCK(sl) pthread_release_lock(sl)
+#define TRY_LOCK(sl) pthread_try_lock(sl)
+#define IS_LOCKED(sl) ((sl)->l)
+
+static MLOCK_T magic_init_mutex = {0, 0, 0 };
+#if HAVE_MORECORE
+static MLOCK_T morecore_mutex = {0, 0, 0 };
+#endif /* HAVE_MORECORE */
+
+#else /* WIN32 */
+/* Custom win32-style spin locks on x86 and x64 for MSC */
+struct win32_mlock_t
+{
+ volatile long threadid;
+ volatile unsigned int c;
+ long l;
+};
+#define MLOCK_T struct win32_mlock_t
+#define CURRENT_THREAD GetCurrentThreadId()
+#define SPINS_PER_YIELD 63
+static FORCEINLINE int win32_acquire_lock (MLOCK_T *sl) {
+ long mythreadid=CURRENT_THREAD;
+ if(mythreadid==sl->threadid)
+ ++sl->c;
+ else {
+ int spins = 0;
+ for (;;) {
+ if (!interlockedexchange(&sl->l, 1)) {
+ assert(!sl->threadid);
+ sl->threadid=mythreadid;
+ sl->c=1;
+ break;
+ }
+ if ((++spins & SPINS_PER_YIELD) == 0)
+ SleepEx(0, FALSE);
+ }
+ }
+ return 0;
+}
+
+static FORCEINLINE void win32_release_lock (MLOCK_T *sl) {
+ assert(CURRENT_THREAD==sl->threadid);
+ if (!--sl->c) {
+ sl->threadid=0;
+ interlockedexchange (&sl->l, 0);
+ }
+}
+
+static FORCEINLINE int win32_try_lock (MLOCK_T *sl) {
+ if (!interlockedexchange(&sl->l, 1)){
+ assert(!sl->threadid);
+ sl->threadid=CURRENT_THREAD;
+ sl->c=1;
+ return 1;
+ }
+ return 0;
+}
+
+#define INITIAL_LOCK(sl) (memset(sl, 0, sizeof(MLOCK_T)), 0)
+#define ACQUIRE_LOCK(sl) win32_acquire_lock(sl)
+#define RELEASE_LOCK(sl) win32_release_lock(sl)
+#define TRY_LOCK(sl) win32_try_lock(sl)
+#define IS_LOCKED(sl) ((sl)->l)
+
+static MLOCK_T magic_init_mutex = {0, 0 };
+#if HAVE_MORECORE
+static MLOCK_T morecore_mutex = {0, 0 };
+#endif /* HAVE_MORECORE */
+
+#endif /* WIN32 */
+#else /* USE_SPIN_LOCKS */
+
+#ifndef WIN32
+/* pthreads-based locks */
+struct pthread_mlock_t
+{
+ volatile unsigned int c;
+ pthread_mutex_t l;
+};
+#define MLOCK_T struct pthread_mlock_t
+#define CURRENT_THREAD pthread_self()
+static FORCEINLINE int pthread_acquire_lock (MLOCK_T *sl) {
+ if(!pthread_mutex_lock(&(sl)->l)){
+ sl->c++;
+ return 0;
+ }
+ return 1;
+}
+
+static FORCEINLINE void pthread_release_lock (MLOCK_T *sl) {
+ --sl->c;
+ pthread_mutex_unlock(&(sl)->l);
+}
+
+static FORCEINLINE int pthread_try_lock (MLOCK_T *sl) {
+ if(!pthread_mutex_trylock(&(sl)->l)){
+ sl->c++;
+ return 1;
+ }
+ return 0;
+}
+
+static FORCEINLINE int pthread_init_lock (MLOCK_T *sl) {
+ pthread_mutexattr_t attr;
+ sl->c=0;
+ if(pthread_mutexattr_init(&attr)) return 1;
+ if(pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) return 1;
+ if(pthread_mutex_init(&sl->l, &attr)) return 1;
+ pthread_mutexattr_destroy(&attr);
+ return 0;
+}
+
+static FORCEINLINE int pthread_islocked (MLOCK_T *sl) {
+ if(!pthread_try_lock(sl)){
+ int ret = (sl->c != 0);
+ pthread_mutex_unlock(sl);
+ return ret;
+ }
+ return 0;
+}
+
+#define INITIAL_LOCK(sl) pthread_init_lock(sl)
+#define ACQUIRE_LOCK(sl) pthread_acquire_lock(sl)
+#define RELEASE_LOCK(sl) pthread_release_lock(sl)
+#define TRY_LOCK(sl) pthread_try_lock(sl)
+#define IS_LOCKED(sl) pthread_islocked(sl)
+
+static MLOCK_T magic_init_mutex = {0, PTHREAD_MUTEX_INITIALIZER };
+#if HAVE_MORECORE
+static MLOCK_T morecore_mutex = {0, PTHREAD_MUTEX_INITIALIZER };
+#endif /* HAVE_MORECORE */
+
+#else /* WIN32 */
+/* Win32 critical sections */
+#define MLOCK_T CRITICAL_SECTION
+#define CURRENT_THREAD GetCurrentThreadId()
+#define INITIAL_LOCK(s) (!InitializeCriticalSectionAndSpinCount((s), 4000)
+#define ACQUIRE_LOCK(s) ( (!((s))->DebugInfo ? INITIAL_LOCK((s)) : 0), !EnterCriticalSection((s)), 0)
+#define RELEASE_LOCK(s) ( LeaveCriticalSection((s)), 0 )
+#define TRY_LOCK(s) ( TryEnterCriticalSection((s)) )
+#define IS_LOCKED(s) ( (s)->LockCount >= 0 )
+#define NULL_LOCK_INITIALIZER
+static MLOCK_T magic_init_mutex;
+#if HAVE_MORECORE
+static MLOCK_T morecore_mutex;
+#endif /* HAVE_MORECORE */
+#endif /* WIN32 */
+#endif /* USE_SPIN_LOCKS */
+#endif /* USE_LOCKS == 1 */
+
+/* ----------------------- User-defined locks ------------------------ */
+
+#if USE_LOCKS > 1
+/* Define your own lock implementation here */
+/* #define INITIAL_LOCK(sl) ... */
+/* #define ACQUIRE_LOCK(sl) ... */
+/* #define RELEASE_LOCK(sl) ... */
+/* #define TRY_LOCK(sl) ... */
+/* #define IS_LOCKED(sl) ... */
+/* #define NULL_LOCK_INITIALIZER ... */
+
+static MLOCK_T magic_init_mutex = NULL_LOCK_INITIALIZER;
+#if HAVE_MORECORE
+static MLOCK_T morecore_mutex = NULL_LOCK_INITIALIZER;
+#endif /* HAVE_MORECORE */
+#endif /* USE_LOCKS > 1 */
+
+/* ----------------------- Lock-based state ------------------------ */
+
+
+#if USE_LOCKS
+#define USE_LOCK_BIT (2U)
+#else /* USE_LOCKS */
+#define USE_LOCK_BIT (0U)
+#define INITIAL_LOCK(l)
+#endif /* USE_LOCKS */
+
+#if USE_LOCKS && HAVE_MORECORE
+#define ACQUIRE_MORECORE_LOCK() ACQUIRE_LOCK(&morecore_mutex);
+#define RELEASE_MORECORE_LOCK() RELEASE_LOCK(&morecore_mutex);
+#else /* USE_LOCKS && HAVE_MORECORE */
+#define ACQUIRE_MORECORE_LOCK()
+#define RELEASE_MORECORE_LOCK()
+#endif /* USE_LOCKS && HAVE_MORECORE */
+
+#if USE_LOCKS
+#define ACQUIRE_MAGIC_INIT_LOCK() ACQUIRE_LOCK(&magic_init_mutex);
+#define RELEASE_MAGIC_INIT_LOCK() RELEASE_LOCK(&magic_init_mutex);
+#else /* USE_LOCKS */
+#define ACQUIRE_MAGIC_INIT_LOCK()
+#define RELEASE_MAGIC_INIT_LOCK()
+#endif /* USE_LOCKS */
+
+
+/* ----------------------- Chunk representations ------------------------ */
+
+/*
+ (The following includes lightly edited explanations by Colin Plumb.)
+
+ The malloc_chunk declaration below is misleading (but accurate and
+ necessary). It declares a "view" into memory allowing access to
+ necessary fields at known offsets from a given base.
+
+ Chunks of memory are maintained using a `boundary tag' method as
+ originally described by Knuth. (See the paper by Paul Wilson
+ ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a survey of such
+ techniques.) Sizes of free chunks are stored both in the front of
+ each chunk and at the end. This makes consolidating fragmented
+ chunks into bigger chunks fast. The head fields also hold bits
+ representing whether chunks are free or in use.
+
+ Here are some pictures to make it clearer. They are "exploded" to
+ show that the state of a chunk can be thought of as extending from
+ the high 31 bits of the head field of its header through the
+ prev_foot and PINUSE_BIT bit of the following chunk header.
+
+ A chunk that's in use looks like:
+
+ chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Size of previous chunk (if P = 1) |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P|
+ | Size of this chunk 1| +-+
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | |
+ +- -+
+ | |
+ +- -+
+ | :
+ +- size - sizeof(size_t) available payload bytes -+
+ : |
+ chunk-> +- -+
+ | |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |1|
+ | Size of next chunk (may or may not be in use) | +-+
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+ And if it's free, it looks like this:
+
+ chunk-> +- -+
+ | User payload (must be in use, or we would have merged!) |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P|
+ | Size of this chunk 0| +-+
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Next pointer |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Prev pointer |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | :
+ +- size - sizeof(struct chunk) unused bytes -+
+ : |
+ chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Size of this chunk |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0|
+ | Size of next chunk (must be in use, or we would have merged)| +-+
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | :
+ +- User payload -+
+ : |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ |0|
+ +-+
+ Note that since we always merge adjacent free chunks, the chunks
+ adjacent to a free chunk must be in use.
+
+ Given a pointer to a chunk (which can be derived trivially from the
+ payload pointer) we can, in O(1) time, find out whether the adjacent
+ chunks are free, and if so, unlink them from the lists that they
+ are on and merge them with the current chunk.
+
+ Chunks always begin on even word boundaries, so the mem portion
+ (which is returned to the user) is also on an even word boundary, and
+ thus at least double-word aligned.
+
+ The P (PINUSE_BIT) bit, stored in the unused low-order bit of the
+ chunk size (which is always a multiple of two words), is an in-use
+ bit for the *previous* chunk. If that bit is *clear*, then the
+ word before the current chunk size contains the previous chunk
+ size, and can be used to find the front of the previous chunk.
+ The very first chunk allocated always has this bit set, preventing
+ access to non-existent (or non-owned) memory. If pinuse is set for
+ any given chunk, then you CANNOT determine the size of the
+ previous chunk, and might even get a memory addressing fault when
+ trying to do so.
+
+ The C (CINUSE_BIT) bit, stored in the unused second-lowest bit of
+ the chunk size redundantly records whether the current chunk is
+ inuse. This redundancy enables usage checks within free and realloc,
+ and reduces indirection when freeing and consolidating chunks.
+
+ Each freshly allocated chunk must have both cinuse and pinuse set.
+ That is, each allocated chunk borders either a previously allocated
+ and still in-use chunk, or the base of its memory arena. This is
+ ensured by making all allocations from the the `lowest' part of any
+ found chunk. Further, no free chunk physically borders another one,
+ so each free chunk is known to be preceded and followed by either
+ inuse chunks or the ends of memory.
+
+ Note that the `foot' of the current chunk is actually represented
+ as the prev_foot of the NEXT chunk. This makes it easier to
+ deal with alignments etc but can be very confusing when trying
+ to extend or adapt this code.
+
+ The exceptions to all this are
+
+ 1. The special chunk `top' is the top-most available chunk (i.e.,
+ the one bordering the end of available memory). It is treated
+ specially. Top is never included in any bin, is used only if
+ no other chunk is available, and is released back to the
+ system if it is very large (see M_TRIM_THRESHOLD). In effect,
+ the top chunk is treated as larger (and thus less well
+ fitting) than any other available chunk. The top chunk
+ doesn't update its trailing size field since there is no next
+ contiguous chunk that would have to index off it. However,
+ space is still allocated for it (TOP_FOOT_SIZE) to enable
+ separation or merging when space is extended.
+
+ 3. Chunks allocated via mmap, which have the lowest-order bit
+ (IS_MMAPPED_BIT) set in their prev_foot fields, and do not set
+ PINUSE_BIT in their head fields. Because they are allocated
+ one-by-one, each must carry its own prev_foot field, which is
+ also used to hold the offset this chunk has within its mmapped
+ region, which is needed to preserve alignment. Each mmapped
+ chunk is trailed by the first two fields of a fake next-chunk
+ for sake of usage checks.
+
+*/
+
+struct malloc_chunk {
+ size_t prev_foot; /* Size of previous chunk (if free). */
+ size_t head; /* Size and inuse bits. */
+ struct malloc_chunk* fd; /* double links -- used only if free. */
+ struct malloc_chunk* bk;
+};
+
+typedef struct malloc_chunk mchunk;
+typedef struct malloc_chunk* mchunkptr;
+typedef struct malloc_chunk* sbinptr; /* The type of bins of chunks */
+typedef unsigned int bindex_t; /* Described below */
+typedef unsigned int binmap_t; /* Described below */
+typedef unsigned int flag_t; /* The type of various bit flag sets */
+
+/* ------------------- Chunks sizes and alignments ----------------------- */
+
+#define MCHUNK_SIZE (sizeof(mchunk))
+
+#if FOOTERS
+#define CHUNK_OVERHEAD (TWO_SIZE_T_SIZES)
+#else /* FOOTERS */
+#define CHUNK_OVERHEAD (SIZE_T_SIZE)
+#endif /* FOOTERS */
+
+/* MMapped chunks need a second word of overhead ... */
+#define MMAP_CHUNK_OVERHEAD (TWO_SIZE_T_SIZES)
+/* ... and additional padding for fake next-chunk at foot */
+#define MMAP_FOOT_PAD (FOUR_SIZE_T_SIZES)
+
+/* The smallest size we can malloc is an aligned minimal chunk */
+#define MIN_CHUNK_SIZE\
+ ((MCHUNK_SIZE + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)
+
+/* conversion from malloc headers to user pointers, and back */
+#define chunk2mem(p) ((void*)((char*)(p) + TWO_SIZE_T_SIZES))
+#define mem2chunk(mem) ((mchunkptr)((char*)(mem) - TWO_SIZE_T_SIZES))
+/* chunk associated with aligned address A */
+#define align_as_chunk(A) (mchunkptr)((A) + align_offset(chunk2mem(A)))
+
+/* Bounds on request (not chunk) sizes. */
+#define MAX_REQUEST ((-MIN_CHUNK_SIZE) << 2)
+#define MIN_REQUEST (MIN_CHUNK_SIZE - CHUNK_OVERHEAD - SIZE_T_ONE)
+
+/* pad request bytes into a usable size */
+#define pad_request(req) \
+ (((req) + CHUNK_OVERHEAD + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)
+
+/* pad request, checking for minimum (but not maximum) */
+#define request2size(req) \
+ (((req) < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(req))
+
+
+/* ------------------ Operations on head and foot fields ----------------- */
+
+/*
+ The head field of a chunk is or'ed with PINUSE_BIT when previous
+ adjacent chunk in use, and or'ed with CINUSE_BIT if this chunk is in
+ use. If the chunk was obtained with mmap, the prev_foot field has
+ IS_MMAPPED_BIT set, otherwise holding the offset of the base of the
+ mmapped region to the base of the chunk.
+
+ FLAG4_BIT is not used by this malloc, but might be useful in extensions.
+*/
+
+#define PINUSE_BIT (SIZE_T_ONE)
+#define CINUSE_BIT (SIZE_T_TWO)
+#define FLAG4_BIT (SIZE_T_FOUR)
+#define INUSE_BITS (PINUSE_BIT|CINUSE_BIT)
+#define FLAG_BITS (PINUSE_BIT|CINUSE_BIT|FLAG4_BIT)
+
+/* Head value for fenceposts */
+#define FENCEPOST_HEAD (INUSE_BITS|SIZE_T_SIZE)
+
+/* extraction of fields from head words */
+#define cinuse(p) ((p)->head & CINUSE_BIT)
+#define pinuse(p) ((p)->head & PINUSE_BIT)
+#define chunksize(p) ((p)->head & ~(FLAG_BITS))
+
+#define clear_pinuse(p) ((p)->head &= ~PINUSE_BIT)
+#define clear_cinuse(p) ((p)->head &= ~CINUSE_BIT)
+
+/* Treat space at ptr +/- offset as a chunk */
+#define chunk_plus_offset(p, s) ((mchunkptr)(((char*)(p)) + (s)))
+#define chunk_minus_offset(p, s) ((mchunkptr)(((char*)(p)) - (s)))
+
+/* Ptr to next or previous physical malloc_chunk. */
+#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->head & ~FLAG_BITS)))
+#define prev_chunk(p) ((mchunkptr)( ((char*)(p)) - ((p)->prev_foot) ))
+
+/* extract next chunk's pinuse bit */
+#define next_pinuse(p) ((next_chunk(p)->head) & PINUSE_BIT)
+
+/* Get/set size at footer */
+#define get_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_foot)
+#define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_foot = (s))
+
+/* Set size, pinuse bit, and foot */
+#define set_size_and_pinuse_of_free_chunk(p, s)\
+ ((p)->head = (s|PINUSE_BIT), set_foot(p, s))
+
+/* Set size, pinuse bit, foot, and clear next pinuse */
+#define set_free_with_pinuse(p, s, n)\
+ (clear_pinuse(n), set_size_and_pinuse_of_free_chunk(p, s))
+
+#define is_mmapped(p)\
+ (!((p)->head & PINUSE_BIT) && ((p)->prev_foot & IS_MMAPPED_BIT))
+
+/* Get the internal overhead associated with chunk p */
+#define overhead_for(p)\
+ (is_mmapped(p)? MMAP_CHUNK_OVERHEAD : CHUNK_OVERHEAD)
+
+/* Return true if malloced space is not necessarily cleared */
+#if MMAP_CLEARS
+#define calloc_must_clear(p) (!is_mmapped(p))
+#else /* MMAP_CLEARS */
+#define calloc_must_clear(p) (1)
+#endif /* MMAP_CLEARS */
+
+/* ---------------------- Overlaid data structures ----------------------- */
+
+/*
+ When chunks are not in use, they are treated as nodes of either
+ lists or trees.
+
+ "Small" chunks are stored in circular doubly-linked lists, and look
+ like this:
+
+ chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Size of previous chunk |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ `head:' | Size of chunk, in bytes |P|
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Forward pointer to next chunk in list |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Back pointer to previous chunk in list |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Unused space (may be 0 bytes long) .
+ . .
+ . |
+nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ `foot:' | Size of chunk, in bytes |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+ Larger chunks are kept in a form of bitwise digital trees (aka
+ tries) keyed on chunksizes. Because malloc_tree_chunks are only for
+ free chunks greater than 256 bytes, their size doesn't impose any
+ constraints on user chunk sizes. Each node looks like:
+
+ chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Size of previous chunk |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ `head:' | Size of chunk, in bytes |P|
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Forward pointer to next chunk of same size |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Back pointer to previous chunk of same size |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Pointer to left child (child[0]) |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Pointer to right child (child[1]) |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Pointer to parent |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | bin index of this chunk |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Unused space .
+ . |
+nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ `foot:' | Size of chunk, in bytes |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+ Each tree holding treenodes is a tree of unique chunk sizes. Chunks
+ of the same size are arranged in a circularly-linked list, with only
+ the oldest chunk (the next to be used, in our FIFO ordering)
+ actually in the tree. (Tree members are distinguished by a non-null
+ parent pointer.) If a chunk with the same size an an existing node
+ is inserted, it is linked off the existing node using pointers that
+ work in the same way as fd/bk pointers of small chunks.
+
+ Each tree contains a power of 2 sized range of chunk sizes (the
+ smallest is 0x100 <= x < 0x180), which is is divided in half at each
+ tree level, with the chunks in the smaller half of the range (0x100
+ <= x < 0x140 for the top nose) in the left subtree and the larger
+ half (0x140 <= x < 0x180) in the right subtree. This is, of course,
+ done by inspecting individual bits.
+
+ Using these rules, each node's left subtree contains all smaller
+ sizes than its right subtree. However, the node at the root of each
+ subtree has no particular ordering relationship to either. (The
+ dividing line between the subtree sizes is based on trie relation.)
+ If we remove the last chunk of a given size from the interior of the
+ tree, we need to replace it with a leaf node. The tree ordering
+ rules permit a node to be replaced by any leaf below it.
+
+ The smallest chunk in a tree (a common operation in a best-fit
+ allocator) can be found by walking a path to the leftmost leaf in
+ the tree. Unlike a usual binary tree, where we follow left child
+ pointers until we reach a null, here we follow the right child
+ pointer any time the left one is null, until we reach a leaf with
+ both child pointers null. The smallest chunk in the tree will be
+ somewhere along that path.
+
+ The worst case number of steps to add, find, or remove a node is
+ bounded by the number of bits differentiating chunks within
+ bins. Under current bin calculations, this ranges from 6 up to 21
+ (for 32 bit sizes) or up to 53 (for 64 bit sizes). The typical case
+ is of course much better.
+*/
+
+struct malloc_tree_chunk {
+ /* The first four fields must be compatible with malloc_chunk */
+ size_t prev_foot;
+ size_t head;
+ struct malloc_tree_chunk* fd;
+ struct malloc_tree_chunk* bk;
+
+ struct malloc_tree_chunk* child[2];
+ struct malloc_tree_chunk* parent;
+ bindex_t index;
+};
+
+typedef struct malloc_tree_chunk tchunk;
+typedef struct malloc_tree_chunk* tchunkptr;
+typedef struct malloc_tree_chunk* tbinptr; /* The type of bins of trees */
+
+/* A little helper macro for trees */
+#define leftmost_child(t) ((t)->child[0] != 0? (t)->child[0] : (t)->child[1])
+
+/* ----------------------------- Segments -------------------------------- */
+
+/*
+ Each malloc space may include non-contiguous segments, held in a
+ list headed by an embedded malloc_segment record representing the
+ top-most space. Segments also include flags holding properties of
+ the space. Large chunks that are directly allocated by mmap are not
+ included in this list. They are instead independently created and
+ destroyed without otherwise keeping track of them.
+
+ Segment management mainly comes into play for spaces allocated by
+ MMAP. Any call to MMAP might or might not return memory that is
+ adjacent to an existing segment. MORECORE normally contiguously
+ extends the current space, so this space is almost always adjacent,
+ which is simpler and faster to deal with. (This is why MORECORE is
+ used preferentially to MMAP when both are available -- see
+ sys_alloc.) When allocating using MMAP, we don't use any of the
+ hinting mechanisms (inconsistently) supported in various
+ implementations of unix mmap, or distinguish reserving from
+ committing memory. Instead, we just ask for space, and exploit
+ contiguity when we get it. It is probably possible to do
+ better than this on some systems, but no general scheme seems
+ to be significantly better.
+
+ Management entails a simpler variant of the consolidation scheme
+ used for chunks to reduce fragmentation -- new adjacent memory is
+ normally prepended or appended to an existing segment. However,
+ there are limitations compared to chunk consolidation that mostly
+ reflect the fact that segment processing is relatively infrequent
+ (occurring only when getting memory from system) and that we
+ don't expect to have huge numbers of segments:
+
+ * Segments are not indexed, so traversal requires linear scans. (It
+ would be possible to index these, but is not worth the extra
+ overhead and complexity for most programs on most platforms.)
+ * New segments are only appended to old ones when holding top-most
+ memory; if they cannot be prepended to others, they are held in
+ different segments.
+
+ Except for the top-most segment of an mstate, each segment record
+ is kept at the tail of its segment. Segments are added by pushing
+ segment records onto the list headed by &mstate.seg for the
+ containing mstate.
+
+ Segment flags control allocation/merge/deallocation policies:
+ * If EXTERN_BIT set, then we did not allocate this segment,
+ and so should not try to deallocate or merge with others.
+ (This currently holds only for the initial segment passed
+ into create_mspace_with_base.)
+ * If IS_MMAPPED_BIT set, the segment may be merged with
+ other surrounding mmapped segments and trimmed/de-allocated
+ using munmap.
+ * If neither bit is set, then the segment was obtained using
+ MORECORE so can be merged with surrounding MORECORE'd segments
+ and deallocated/trimmed using MORECORE with negative arguments.
+*/
+
+struct malloc_segment {
+ char* base; /* base address */
+ size_t size; /* allocated size */
+ struct malloc_segment* next; /* ptr to next segment */
+ flag_t sflags; /* mmap and extern flag */
+};
+
+#define is_mmapped_segment(S) ((S)->sflags & IS_MMAPPED_BIT)
+#define is_extern_segment(S) ((S)->sflags & EXTERN_BIT)
+
+typedef struct malloc_segment msegment;
+typedef struct malloc_segment* msegmentptr;
+
+/* ---------------------------- malloc_state ----------------------------- */
+
+/*
+ A malloc_state holds all of the bookkeeping for a space.
+ The main fields are:
+
+ Top
+ The topmost chunk of the currently active segment. Its size is
+ cached in topsize. The actual size of topmost space is
+ topsize+TOP_FOOT_SIZE, which includes space reserved for adding
+ fenceposts and segment records if necessary when getting more
+ space from the system. The size at which to autotrim top is
+ cached from mparams in trim_check, except that it is disabled if
+ an autotrim fails.
+
+ Designated victim (dv)
+ This is the preferred chunk for servicing small requests that
+ don't have exact fits. It is normally the chunk split off most
+ recently to service another small request. Its size is cached in
+ dvsize. The link fields of this chunk are not maintained since it
+ is not kept in a bin.
+
+ SmallBins
+ An array of bin headers for free chunks. These bins hold chunks
+ with sizes less than MIN_LARGE_SIZE bytes. Each bin contains
+ chunks of all the same size, spaced 8 bytes apart. To simplify
+ use in double-linked lists, each bin header acts as a malloc_chunk
+ pointing to the real first node, if it exists (else pointing to
+ itself). This avoids special-casing for headers. But to avoid
+ waste, we allocate only the fd/bk pointers of bins, and then use
+ repositioning tricks to treat these as the fields of a chunk.
+
+ TreeBins
+ Treebins are pointers to the roots of trees holding a range of
+ sizes. There are 2 equally spaced treebins for each power of two
+ from TREE_SHIFT to TREE_SHIFT+16. The last bin holds anything
+ larger.
+
+ Bin maps
+ There is one bit map for small bins ("smallmap") and one for
+ treebins ("treemap). Each bin sets its bit when non-empty, and
+ clears the bit when empty. Bit operations are then used to avoid
+ bin-by-bin searching -- nearly all "search" is done without ever
+ looking at bins that won't be selected. The bit maps
+ conservatively use 32 bits per map word, even if on 64bit system.
+ For a good description of some of the bit-based techniques used
+ here, see Henry S. Warren Jr's book "Hacker's Delight" (and
+ supplement at http://hackersdelight.org/). Many of these are
+ intended to reduce the branchiness of paths through malloc etc, as
+ well as to reduce the number of memory locations read or written.
+
+ Segments
+ A list of segments headed by an embedded malloc_segment record
+ representing the initial space.
+
+ Address check support
+ The least_addr field is the least address ever obtained from
+ MORECORE or MMAP. Attempted frees and reallocs of any address less
+ than this are trapped (unless INSECURE is defined).
+
+ Magic tag
+ A cross-check field that should always hold same value as mparams.magic.
+
+ Flags
+ Bits recording whether to use MMAP, locks, or contiguous MORECORE
+
+ Statistics
+ Each space keeps track of current and maximum system memory
+ obtained via MORECORE or MMAP.
+
+ Trim support
+ Fields holding the amount of unused topmost memory that should trigger
+ timming, and a counter to force periodic scanning to release unused
+ non-topmost segments.
+
+ Locking
+ If USE_LOCKS is defined, the "mutex" lock is acquired and released
+ around every public call using this mspace.
+
+ Extension support
+ A void* pointer and a size_t field that can be used to help implement
+ extensions to this malloc.
+*/
+
+/* Bin types, widths and sizes */
+#define NSMALLBINS (32U)
+#define NTREEBINS (32U)
+#define SMALLBIN_SHIFT (3U)
+#define SMALLBIN_WIDTH (SIZE_T_ONE << SMALLBIN_SHIFT)
+#define TREEBIN_SHIFT (8U)
+#define MIN_LARGE_SIZE (SIZE_T_ONE << TREEBIN_SHIFT)
+#define MAX_SMALL_SIZE (MIN_LARGE_SIZE - SIZE_T_ONE)
+#define MAX_SMALL_REQUEST (MAX_SMALL_SIZE - CHUNK_ALIGN_MASK - CHUNK_OVERHEAD)
+
+struct malloc_state {
+ binmap_t smallmap;
+ binmap_t treemap;
+ size_t dvsize;
+ size_t topsize;
+ char* least_addr;
+ mchunkptr dv;
+ mchunkptr top;
+ size_t trim_check;
+ size_t release_checks;
+ size_t magic;
+ mchunkptr smallbins[(NSMALLBINS+1)*2];
+ tbinptr treebins[NTREEBINS];
+ size_t footprint;
+ size_t max_footprint;
+ flag_t mflags;
+#if USE_LOCKS
+ MLOCK_T mutex; /* locate lock among fields that rarely change */
+#endif /* USE_LOCKS */
+ msegment seg;
+ void* extp; /* Unused but available for extensions */
+ size_t exts;
+};
+
+typedef struct malloc_state* mstate;
+
+/* ------------- Global malloc_state and malloc_params ------------------- */
+
+/*
+ malloc_params holds global properties, including those that can be
+ dynamically set using mallopt. There is a single instance, mparams,
+ initialized in init_mparams.
+*/
+
+struct malloc_params {
+ size_t magic;
+ size_t page_size;
+ size_t granularity;
+ size_t mmap_threshold;
+ size_t trim_threshold;
+ flag_t default_mflags;
+};
+
+static struct malloc_params mparams;
+
+#if !ONLY_MSPACES
+
+/* The global malloc_state used for all non-"mspace" calls */
+static struct malloc_state _gm_;
+#define gm (&_gm_)
+#define is_global(M) ((M) == &_gm_)
+
+#endif /* !ONLY_MSPACES */
+
+#define is_initialized(M) ((M)->top != 0)
+
+/* -------------------------- system alloc setup ------------------------- */
+
+/* Operations on mflags */
+
+#define use_lock(M) ((M)->mflags & USE_LOCK_BIT)
+#define enable_lock(M) ((M)->mflags |= USE_LOCK_BIT)
+#define disable_lock(M) ((M)->mflags &= ~USE_LOCK_BIT)
+
+#define use_mmap(M) ((M)->mflags & USE_MMAP_BIT)
+#define enable_mmap(M) ((M)->mflags |= USE_MMAP_BIT)
+#define disable_mmap(M) ((M)->mflags &= ~USE_MMAP_BIT)
+
+#define use_noncontiguous(M) ((M)->mflags & USE_NONCONTIGUOUS_BIT)
+#define disable_contiguous(M) ((M)->mflags |= USE_NONCONTIGUOUS_BIT)
+
+#define set_lock(M,L)\
+ ((M)->mflags = (L)?\
+ ((M)->mflags | USE_LOCK_BIT) :\
+ ((M)->mflags & ~USE_LOCK_BIT))
+
+/* page-align a size */
+#define page_align(S)\
+ (((S) + (mparams.page_size - SIZE_T_ONE)) & ~(mparams.page_size - SIZE_T_ONE))
+
+/* granularity-align a size */
+#define granularity_align(S)\
+ (((S) + (mparams.granularity - SIZE_T_ONE))\
+ & ~(mparams.granularity - SIZE_T_ONE))
+
+
+/* For mmap, use granularity alignment on windows, else page-align */
+#ifdef WIN32
+#define mmap_align(S) granularity_align(S)
+#else
+#define mmap_align(S) page_align(S)
+#endif
+
+#define is_page_aligned(S)\
+ (((size_t)(S) & (mparams.page_size - SIZE_T_ONE)) == 0)
+#define is_granularity_aligned(S)\
+ (((size_t)(S) & (mparams.granularity - SIZE_T_ONE)) == 0)
+
+/* True if segment S holds address A */
+#define segment_holds(S, A)\
+ ((char*)(A) >= S->base && (char*)(A) < S->base + S->size)
+
+/* Return segment holding given address */
+static msegmentptr segment_holding(mstate m, char* addr) {
+ msegmentptr sp = &m->seg;
+ for (;;) {
+ if (addr >= sp->base && addr < sp->base + sp->size)
+ return sp;
+ if ((sp = sp->next) == 0)
+ return 0;
+ }
+}
+
+/* Return true if segment contains a segment link */
+static int has_segment_link(mstate m, msegmentptr ss) {
+ msegmentptr sp = &m->seg;
+ for (;;) {
+ if ((char*)sp >= ss->base && (char*)sp < ss->base + ss->size)
+ return 1;
+ if ((sp = sp->next) == 0)
+ return 0;
+ }
+}
+
+#ifndef MORECORE_CANNOT_TRIM
+#define should_trim(M,s) ((s) > (M)->trim_check)
+#else /* MORECORE_CANNOT_TRIM */
+#define should_trim(M,s) (0)
+#endif /* MORECORE_CANNOT_TRIM */
+
+/*
+ TOP_FOOT_SIZE is padding at the end of a segment, including space
+ that may be needed to place segment records and fenceposts when new
+ noncontiguous segments are added.
+*/
+#define TOP_FOOT_SIZE\
+ (align_offset(chunk2mem(0))+pad_request(sizeof(struct malloc_segment))+MIN_CHUNK_SIZE)
+
+
+/* ------------------------------- Hooks -------------------------------- */
+
+/*
+ PREACTION should be defined to return 0 on success, and nonzero on
+ failure. If you are not using locking, you can redefine these to do
+ anything you like.
+*/
+
+#if USE_LOCKS
+
+/* Ensure locks are initialized */
+#define GLOBALLY_INITIALIZE() (mparams.page_size == 0 && init_mparams())
+
+#define PREACTION(M) ((GLOBALLY_INITIALIZE() || use_lock(M))? ACQUIRE_LOCK(&(M)->mutex) : 0)
+#define POSTACTION(M) { if (use_lock(M)) RELEASE_LOCK(&(M)->mutex); }
+#else /* USE_LOCKS */
+
+#ifndef PREACTION
+#define PREACTION(M) (0)
+#endif /* PREACTION */
+
+#ifndef POSTACTION
+#define POSTACTION(M)
+#endif /* POSTACTION */
+
+#endif /* USE_LOCKS */
+
+/*
+ CORRUPTION_ERROR_ACTION is triggered upon detected bad addresses.
+ USAGE_ERROR_ACTION is triggered on detected bad frees and
+ reallocs. The argument p is an address that might have triggered the
+ fault. It is ignored by the two predefined actions, but might be
+ useful in custom actions that try to help diagnose errors.
+*/
+
+#if PROCEED_ON_ERROR
+
+/* A count of the number of corruption errors causing resets */
+int malloc_corruption_error_count;
+
+/* default corruption action */
+static void reset_on_error(mstate m);
+
+#define CORRUPTION_ERROR_ACTION(m) reset_on_error(m)
+#define USAGE_ERROR_ACTION(m, p)
+
+#else /* PROCEED_ON_ERROR */
+
+#ifndef CORRUPTION_ERROR_ACTION
+#define CORRUPTION_ERROR_ACTION(m) ABORT
+#endif /* CORRUPTION_ERROR_ACTION */
+
+#ifndef USAGE_ERROR_ACTION
+#define USAGE_ERROR_ACTION(m,p) ABORT
+#endif /* USAGE_ERROR_ACTION */
+
+#endif /* PROCEED_ON_ERROR */
+
+/* -------------------------- Debugging setup ---------------------------- */
+
+#if ! DEBUG
+
+#define check_free_chunk(M,P)
+#define check_inuse_chunk(M,P)
+#define check_malloced_chunk(M,P,N)
+#define check_mmapped_chunk(M,P)
+#define check_malloc_state(M)
+#define check_top_chunk(M,P)
+
+#else /* DEBUG */
+#define check_free_chunk(M,P) do_check_free_chunk(M,P)
+#define check_inuse_chunk(M,P) do_check_inuse_chunk(M,P)
+#define check_top_chunk(M,P) do_check_top_chunk(M,P)
+#define check_malloced_chunk(M,P,N) do_check_malloced_chunk(M,P,N)
+#define check_mmapped_chunk(M,P) do_check_mmapped_chunk(M,P)
+#define check_malloc_state(M) do_check_malloc_state(M)
+
+static void do_check_any_chunk(mstate m, mchunkptr p);
+static void do_check_top_chunk(mstate m, mchunkptr p);
+static void do_check_mmapped_chunk(mstate m, mchunkptr p);
+static void do_check_inuse_chunk(mstate m, mchunkptr p);
+static void do_check_free_chunk(mstate m, mchunkptr p);
+static void do_check_malloced_chunk(mstate m, void* mem, size_t s);
+static void do_check_tree(mstate m, tchunkptr t);
+static void do_check_treebin(mstate m, bindex_t i);
+static void do_check_smallbin(mstate m, bindex_t i);
+static void do_check_malloc_state(mstate m);
+static int bin_find(mstate m, mchunkptr x);
+static size_t traverse_and_check(mstate m);
+#endif /* DEBUG */
+
+/* ---------------------------- Indexing Bins ---------------------------- */
+
+#define is_small(s) (((s) >> SMALLBIN_SHIFT) < NSMALLBINS)
+#define small_index(s) ((s) >> SMALLBIN_SHIFT)
+#define small_index2size(i) ((i) << SMALLBIN_SHIFT)
+#define MIN_SMALL_INDEX (small_index(MIN_CHUNK_SIZE))
+
+/* addressing by index. See above about smallbin repositioning */
+#define smallbin_at(M, i) ((sbinptr)((char*)&((M)->smallbins[(i)<<1])))
+#define treebin_at(M,i) (&((M)->treebins[i]))
+
+/* assign tree index for size S to variable I */
+#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+#define compute_tree_index(S, I)\
+{\
+ unsigned int X = S >> TREEBIN_SHIFT;\
+ if (X == 0)\
+ I = 0;\
+ else if (X > 0xFFFF)\
+ I = NTREEBINS-1;\
+ else {\
+ unsigned int K;\
+ __asm__("bsrl\t%1, %0\n\t" : "=r" (K) : "g" (X));\
+ I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
+ }\
+}
+
+#elif defined(_MSC_VER) && _MSC_VER>=1300
+#define compute_tree_index(S, I)\
+{\
+ size_t X = S >> TREEBIN_SHIFT;\
+ if (X == 0)\
+ I = 0;\
+ else if (X > 0xFFFF)\
+ I = NTREEBINS-1;\
+ else {\
+ unsigned int K;\
+ _BitScanReverse((DWORD *) &K, X);\
+ I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
+ }\
+}
+#else /* GNUC */
+#define compute_tree_index(S, I)\
+{\
+ size_t X = S >> TREEBIN_SHIFT;\
+ if (X == 0)\
+ I = 0;\
+ else if (X > 0xFFFF)\
+ I = NTREEBINS-1;\
+ else {\
+ unsigned int Y = (unsigned int)X;\
+ unsigned int N = ((Y - 0x100) >> 16) & 8;\
+ unsigned int K = (((Y <<= N) - 0x1000) >> 16) & 4;\
+ N += K;\
+ N += K = (((Y <<= K) - 0x4000) >> 16) & 2;\
+ K = 14 - N + ((Y <<= K) >> 15);\
+ I = (K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1));\
+ }\
+}
+#endif /* GNUC */
+
+/* Bit representing maximum resolved size in a treebin at i */
+#define bit_for_tree_index(i) \
+ (i == NTREEBINS-1)? (SIZE_T_BITSIZE-1) : (((i) >> 1) + TREEBIN_SHIFT - 2)
+
+/* Shift placing maximum resolved bit in a treebin at i as sign bit */
+#define leftshift_for_tree_index(i) \
+ ((i == NTREEBINS-1)? 0 : \
+ ((SIZE_T_BITSIZE-SIZE_T_ONE) - (((i) >> 1) + TREEBIN_SHIFT - 2)))
+
+/* The size of the smallest chunk held in bin with index i */
+#define minsize_for_tree_index(i) \
+ ((SIZE_T_ONE << (((i) >> 1) + TREEBIN_SHIFT)) | \
+ (((size_t)((i) & SIZE_T_ONE)) << (((i) >> 1) + TREEBIN_SHIFT - 1)))
+
+
+/* ------------------------ Operations on bin maps ----------------------- */
+
+/* bit corresponding to given index */
+#define idx2bit(i) ((binmap_t)(1) << (i))
+
+/* Mark/Clear bits with given index */
+#define mark_smallmap(M,i) ((M)->smallmap |= idx2bit(i))
+#define clear_smallmap(M,i) ((M)->smallmap &= ~idx2bit(i))
+#define smallmap_is_marked(M,i) ((M)->smallmap & idx2bit(i))
+
+#define mark_treemap(M,i) ((M)->treemap |= idx2bit(i))
+#define clear_treemap(M,i) ((M)->treemap &= ~idx2bit(i))
+#define treemap_is_marked(M,i) ((M)->treemap & idx2bit(i))
+
+/* index corresponding to given bit */
+
+#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+#define compute_bit2idx(X, I)\
+{\
+ unsigned int J;\
+ __asm__("bsfl\t%1, %0\n\t" : "=r" (J) : "g" (X));\
+ I = (bindex_t)J;\
+}
+#elif defined(_MSC_VER) && _MSC_VER>=1300
+#define compute_bit2idx(X, I)\
+{\
+ unsigned int J;\
+ _BitScanForward((DWORD *) &J, X);\
+ I = (bindex_t)J;\
+}
+
+#else /* GNUC */
+#if USE_BUILTIN_FFS
+#define compute_bit2idx(X, I) I = ffs(X)-1
+
+#else /* USE_BUILTIN_FFS */
+#define compute_bit2idx(X, I)\
+{\
+ unsigned int Y = X - 1;\
+ unsigned int K = Y >> (16-4) & 16;\
+ unsigned int N = K; Y >>= K;\
+ N += K = Y >> (8-3) & 8; Y >>= K;\
+ N += K = Y >> (4-2) & 4; Y >>= K;\
+ N += K = Y >> (2-1) & 2; Y >>= K;\
+ N += K = Y >> (1-0) & 1; Y >>= K;\
+ I = (bindex_t)(N + Y);\
+}
+#endif /* USE_BUILTIN_FFS */
+#endif /* GNUC */
+
+/* isolate the least set bit of a bitmap */
+#define least_bit(x) ((x) & -(x))
+
+/* mask with all bits to left of least bit of x on */
+#define left_bits(x) ((x<<1) | -(x<<1))
+
+/* mask with all bits to left of or equal to least bit of x on */
+#define same_or_left_bits(x) ((x) | -(x))
+
+
+/* ----------------------- Runtime Check Support ------------------------- */
+
+/*
+ For security, the main invariant is that malloc/free/etc never
+ writes to a static address other than malloc_state, unless static
+ malloc_state itself has been corrupted, which cannot occur via
+ malloc (because of these checks). In essence this means that we
+ believe all pointers, sizes, maps etc held in malloc_state, but
+ check all of those linked or offsetted from other embedded data
+ structures. These checks are interspersed with main code in a way
+ that tends to minimize their run-time cost.
+
+ When FOOTERS is defined, in addition to range checking, we also
+ verify footer fields of inuse chunks, which can be used guarantee
+ that the mstate controlling malloc/free is intact. This is a
+ streamlined version of the approach described by William Robertson
+ et al in "Run-time Detection of Heap-based Overflows" LISA'03
+ http://www.usenix.org/events/lisa03/tech/robertson.html The footer
+ of an inuse chunk holds the xor of its mstate and a random seed,
+ that is checked upon calls to free() and realloc(). This is
+ (probablistically) unguessable from outside the program, but can be
+ computed by any code successfully malloc'ing any chunk, so does not
+ itself provide protection against code that has already broken
+ security through some other means. Unlike Robertson et al, we
+ always dynamically check addresses of all offset chunks (previous,
+ next, etc). This turns out to be cheaper than relying on hashes.
+*/
+
+#if !INSECURE
+/* Check if address a is at least as high as any from MORECORE or MMAP */
+#define ok_address(M, a) ((char*)(a) >= (M)->least_addr)
+/* Check if address of next chunk n is higher than base chunk p */
+#define ok_next(p, n) ((char*)(p) < (char*)(n))
+/* Check if p has its cinuse bit on */
+#define ok_cinuse(p) cinuse(p)
+/* Check if p has its pinuse bit on */
+#define ok_pinuse(p) pinuse(p)
+
+#else /* !INSECURE */
+#define ok_address(M, a) (1)
+#define ok_next(b, n) (1)
+#define ok_cinuse(p) (1)
+#define ok_pinuse(p) (1)
+#endif /* !INSECURE */
+
+#if (FOOTERS && !INSECURE)
+/* Check if (alleged) mstate m has expected magic field */
+#define ok_magic(M) ((M)->magic == mparams.magic)
+#else /* (FOOTERS && !INSECURE) */
+#define ok_magic(M) (1)
+#endif /* (FOOTERS && !INSECURE) */
+
+
+/* In gcc, use __builtin_expect to minimize impact of checks */
+#if !INSECURE
+#if defined(__GNUC__) && __GNUC__ >= 3
+#define RTCHECK(e) __builtin_expect(e, 1)
+#else /* GNUC */
+#define RTCHECK(e) (e)
+#endif /* GNUC */
+#else /* !INSECURE */
+#define RTCHECK(e) (1)
+#endif /* !INSECURE */
+
+/* macros to set up inuse chunks with or without footers */
+
+#if !FOOTERS
+
+#define mark_inuse_foot(M,p,s)
+
+/* Set cinuse bit and pinuse bit of next chunk */
+#define set_inuse(M,p,s)\
+ ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\
+ ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT)
+
+/* Set cinuse and pinuse of this chunk and pinuse of next chunk */
+#define set_inuse_and_pinuse(M,p,s)\
+ ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
+ ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT)
+
+/* Set size, cinuse and pinuse bit of this chunk */
+#define set_size_and_pinuse_of_inuse_chunk(M, p, s)\
+ ((p)->head = (s|PINUSE_BIT|CINUSE_BIT))
+
+#else /* FOOTERS */
+
+/* Set foot of inuse chunk to be xor of mstate and seed */
+#define mark_inuse_foot(M,p,s)\
+ (((mchunkptr)((char*)(p) + (s)))->prev_foot = ((size_t)(M) ^ mparams.magic))
+
+#define get_mstate_for(p)\
+ ((mstate)(((mchunkptr)((char*)(p) +\
+ (chunksize(p))))->prev_foot ^ mparams.magic))
+
+#define set_inuse(M,p,s)\
+ ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\
+ (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT), \
+ mark_inuse_foot(M,p,s))
+
+#define set_inuse_and_pinuse(M,p,s)\
+ ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
+ (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT),\
+ mark_inuse_foot(M,p,s))
+
+#define set_size_and_pinuse_of_inuse_chunk(M, p, s)\
+ ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
+ mark_inuse_foot(M, p, s))
+
+#endif /* !FOOTERS */
+
+/* ---------------------------- setting mparams -------------------------- */
+
+/* Initialize mparams */
+static int init_mparams(void) {
+ if (mparams.page_size == 0) {
+ size_t s;
+
+ mparams.mmap_threshold = DEFAULT_MMAP_THRESHOLD;
+ mparams.trim_threshold = DEFAULT_TRIM_THRESHOLD;
+#if MORECORE_CONTIGUOUS
+ mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT;
+#else /* MORECORE_CONTIGUOUS */
+ mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT|USE_NONCONTIGUOUS_BIT;
+#endif /* MORECORE_CONTIGUOUS */
+
+#if (FOOTERS && !INSECURE)
+ {
+#if USE_DEV_RANDOM
+ int fd;
+ unsigned char buf[sizeof(size_t)];
+ /* Try to use /dev/urandom, else fall back on using time */
+ if ((fd = open("/dev/urandom", O_RDONLY)) >= 0 &&
+ read(fd, buf, sizeof(buf)) == sizeof(buf)) {
+ s = *((size_t *) buf);
+ close(fd);
+ }
+ else
+#endif /* USE_DEV_RANDOM */
+ s = (size_t)(time(0) ^ (size_t)0x55555555U);
+
+ s |= (size_t)8U; /* ensure nonzero */
+ s &= ~(size_t)7U; /* improve chances of fault for bad values */
+
+ }
+#else /* (FOOTERS && !INSECURE) */
+ s = (size_t)0x58585858U;
+#endif /* (FOOTERS && !INSECURE) */
+ ACQUIRE_MAGIC_INIT_LOCK();
+ if (mparams.magic == 0) {
+ mparams.magic = s;
+#if !ONLY_MSPACES
+ /* Set up lock for main malloc area */
+ INITIAL_LOCK(&gm->mutex);
+ gm->mflags = mparams.default_mflags;
+#endif
+ }
+ RELEASE_MAGIC_INIT_LOCK();
+
+#ifndef WIN32
+ mparams.page_size = malloc_getpagesize;
+ mparams.granularity = ((DEFAULT_GRANULARITY != 0)?
+ DEFAULT_GRANULARITY : mparams.page_size);
+#else /* WIN32 */
+ {
+ SYSTEM_INFO system_info;
+ GetSystemInfo(&system_info);
+ mparams.page_size = system_info.dwPageSize;
+ mparams.granularity = system_info.dwAllocationGranularity;
+ }
+#endif /* WIN32 */
+
+ /* Sanity-check configuration:
+ size_t must be unsigned and as wide as pointer type.
+ ints must be at least 4 bytes.
+ alignment must be at least 8.
+ Alignment, min chunk size, and page size must all be powers of 2.
+ */
+ if ((sizeof(size_t) != sizeof(char*)) ||
+ (MAX_SIZE_T < MIN_CHUNK_SIZE) ||
+ (sizeof(int) < 4) ||
+ (MALLOC_ALIGNMENT < (size_t)8U) ||
+ ((MALLOC_ALIGNMENT & (MALLOC_ALIGNMENT-SIZE_T_ONE)) != 0) ||
+ ((MCHUNK_SIZE & (MCHUNK_SIZE-SIZE_T_ONE)) != 0) ||
+ ((mparams.granularity & (mparams.granularity-SIZE_T_ONE)) != 0) ||
+ ((mparams.page_size & (mparams.page_size-SIZE_T_ONE)) != 0))
+ ABORT;
+ }
+ return 0;
+}
+
+/* support for mallopt */
+static int change_mparam(int param_number, int value) {
+ size_t val = (size_t)value;
+ init_mparams();
+ switch(param_number) {
+ case M_TRIM_THRESHOLD:
+ mparams.trim_threshold = val;
+ return 1;
+ case M_GRANULARITY:
+ if (val >= mparams.page_size && ((val & (val-1)) == 0)) {
+ mparams.granularity = val;
+ return 1;
+ }
+ else
+ return 0;
+ case M_MMAP_THRESHOLD:
+ mparams.mmap_threshold = val;
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+#if DEBUG
+/* ------------------------- Debugging Support --------------------------- */
+
+/* Check properties of any chunk, whether free, inuse, mmapped etc */
+static void do_check_any_chunk(mstate m, mchunkptr p) {
+ assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
+ assert(ok_address(m, p));
+}
+
+/* Check properties of top chunk */
+static void do_check_top_chunk(mstate m, mchunkptr p) {
+ msegmentptr sp = segment_holding(m, (char*)p);
+ size_t sz = p->head & ~INUSE_BITS; /* third-lowest bit can be set! */
+ assert(sp != 0);
+ assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
+ assert(ok_address(m, p));
+ assert(sz == m->topsize);
+ assert(sz > 0);
+ assert(sz == ((sp->base + sp->size) - (char*)p) - TOP_FOOT_SIZE);
+ assert(pinuse(p));
+ assert(!pinuse(chunk_plus_offset(p, sz)));
+}
+
+/* Check properties of (inuse) mmapped chunks */
+static void do_check_mmapped_chunk(mstate m, mchunkptr p) {
+ size_t sz = chunksize(p);
+ size_t len = (sz + (p->prev_foot & ~IS_MMAPPED_BIT) + MMAP_FOOT_PAD);
+ assert(is_mmapped(p));
+ assert(use_mmap(m));
+ assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
+ assert(ok_address(m, p));
+ assert(!is_small(sz));
+ assert((len & (mparams.page_size-SIZE_T_ONE)) == 0);
+ assert(chunk_plus_offset(p, sz)->head == FENCEPOST_HEAD);
+ assert(chunk_plus_offset(p, sz+SIZE_T_SIZE)->head == 0);
+}
+
+/* Check properties of inuse chunks */
+static void do_check_inuse_chunk(mstate m, mchunkptr p) {
+ do_check_any_chunk(m, p);
+ assert(cinuse(p));
+ assert(next_pinuse(p));
+ /* If not pinuse and not mmapped, previous chunk has OK offset */
+ assert(is_mmapped(p) || pinuse(p) || next_chunk(prev_chunk(p)) == p);
+ if (is_mmapped(p))
+ do_check_mmapped_chunk(m, p);
+}
+
+/* Check properties of free chunks */
+static void do_check_free_chunk(mstate m, mchunkptr p) {
+ size_t sz = chunksize(p);
+ mchunkptr next = chunk_plus_offset(p, sz);
+ do_check_any_chunk(m, p);
+ assert(!cinuse(p));
+ assert(!next_pinuse(p));
+ assert (!is_mmapped(p));
+ if (p != m->dv && p != m->top) {
+ if (sz >= MIN_CHUNK_SIZE) {
+ assert((sz & CHUNK_ALIGN_MASK) == 0);
+ assert(is_aligned(chunk2mem(p)));
+ assert(next->prev_foot == sz);
+ assert(pinuse(p));
+ assert (next == m->top || cinuse(next));
+ assert(p->fd->bk == p);
+ assert(p->bk->fd == p);
+ }
+ else /* markers are always of size SIZE_T_SIZE */
+ assert(sz == SIZE_T_SIZE);
+ }
+}
+
+/* Check properties of malloced chunks at the point they are malloced */
+static void do_check_malloced_chunk(mstate m, void* mem, size_t s) {
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+ size_t sz = p->head & ~(PINUSE_BIT|CINUSE_BIT);
+ do_check_inuse_chunk(m, p);
+ assert((sz & CHUNK_ALIGN_MASK) == 0);
+ assert(sz >= MIN_CHUNK_SIZE);
+ assert(sz >= s);
+ /* unless mmapped, size is less than MIN_CHUNK_SIZE more than request */
+ assert(is_mmapped(p) || sz < (s + MIN_CHUNK_SIZE));
+ }
+}
+
+/* Check a tree and its subtrees. */
+static void do_check_tree(mstate m, tchunkptr t) {
+ tchunkptr head = 0;
+ tchunkptr u = t;
+ bindex_t tindex = t->index;
+ size_t tsize = chunksize(t);
+ bindex_t idx;
+ compute_tree_index(tsize, idx);
+ assert(tindex == idx);
+ assert(tsize >= MIN_LARGE_SIZE);
+ assert(tsize >= minsize_for_tree_index(idx));
+ assert((idx == NTREEBINS-1) || (tsize < minsize_for_tree_index((idx+1))));
+
+ do { /* traverse through chain of same-sized nodes */
+ do_check_any_chunk(m, ((mchunkptr)u));
+ assert(u->index == tindex);
+ assert(chunksize(u) == tsize);
+ assert(!cinuse(u));
+ assert(!next_pinuse(u));
+ assert(u->fd->bk == u);
+ assert(u->bk->fd == u);
+ if (u->parent == 0) {
+ assert(u->child[0] == 0);
+ assert(u->child[1] == 0);
+ }
+ else {
+ assert(head == 0); /* only one node on chain has parent */
+ head = u;
+ assert(u->parent != u);
+ assert (u->parent->child[0] == u ||
+ u->parent->child[1] == u ||
+ *((tbinptr*)(u->parent)) == u);
+ if (u->child[0] != 0) {
+ assert(u->child[0]->parent == u);
+ assert(u->child[0] != u);
+ do_check_tree(m, u->child[0]);
+ }
+ if (u->child[1] != 0) {
+ assert(u->child[1]->parent == u);
+ assert(u->child[1] != u);
+ do_check_tree(m, u->child[1]);
+ }
+ if (u->child[0] != 0 && u->child[1] != 0) {
+ assert(chunksize(u->child[0]) < chunksize(u->child[1]));
+ }
+ }
+ u = u->fd;
+ } while (u != t);
+ assert(head != 0);
+}
+
+/* Check all the chunks in a treebin. */
+static void do_check_treebin(mstate m, bindex_t i) {
+ tbinptr* tb = treebin_at(m, i);
+ tchunkptr t = *tb;
+ int empty = (m->treemap & (1U << i)) == 0;
+ if (t == 0)
+ assert(empty);
+ if (!empty)
+ do_check_tree(m, t);
+}
+
+/* Check all the chunks in a smallbin. */
+static void do_check_smallbin(mstate m, bindex_t i) {
+ sbinptr b = smallbin_at(m, i);
+ mchunkptr p = b->bk;
+ unsigned int empty = (m->smallmap & (1U << i)) == 0;
+ if (p == b)
+ assert(empty);
+ if (!empty) {
+ for (; p != b; p = p->bk) {
+ size_t size = chunksize(p);
+ mchunkptr q;
+ /* each chunk claims to be free */
+ do_check_free_chunk(m, p);
+ /* chunk belongs in bin */
+ assert(small_index(size) == i);
+ assert(p->bk == b || chunksize(p->bk) == chunksize(p));
+ /* chunk is followed by an inuse chunk */
+ q = next_chunk(p);
+ if (q->head != FENCEPOST_HEAD)
+ do_check_inuse_chunk(m, q);
+ }
+ }
+}
+
+/* Find x in a bin. Used in other check functions. */
+static int bin_find(mstate m, mchunkptr x) {
+ size_t size = chunksize(x);
+ if (is_small(size)) {
+ bindex_t sidx = small_index(size);
+ sbinptr b = smallbin_at(m, sidx);
+ if (smallmap_is_marked(m, sidx)) {
+ mchunkptr p = b;
+ do {
+ if (p == x)
+ return 1;
+ } while ((p = p->fd) != b);
+ }
+ }
+ else {
+ bindex_t tidx;
+ compute_tree_index(size, tidx);
+ if (treemap_is_marked(m, tidx)) {
+ tchunkptr t = *treebin_at(m, tidx);
+ size_t sizebits = size << leftshift_for_tree_index(tidx);
+ while (t != 0 && chunksize(t) != size) {
+ t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1];
+ sizebits <<= 1;
+ }
+ if (t != 0) {
+ tchunkptr u = t;
+ do {
+ if (u == (tchunkptr)x)
+ return 1;
+ } while ((u = u->fd) != t);
+ }
+ }
+ }
+ return 0;
+}
+
+/* Traverse each chunk and check it; return total */
+static size_t traverse_and_check(mstate m) {
+ size_t sum = 0;
+ if (is_initialized(m)) {
+ msegmentptr s = &m->seg;
+ sum += m->topsize + TOP_FOOT_SIZE;
+ while (s != 0) {
+ mchunkptr q = align_as_chunk(s->base);
+ mchunkptr lastq = 0;
+ assert(pinuse(q));
+ while (segment_holds(s, q) &&
+ q != m->top && q->head != FENCEPOST_HEAD) {
+ sum += chunksize(q);
+ if (cinuse(q)) {
+ assert(!bin_find(m, q));
+ do_check_inuse_chunk(m, q);
+ }
+ else {
+ assert(q == m->dv || bin_find(m, q));
+ assert(lastq == 0 || cinuse(lastq)); /* Not 2 consecutive free */
+ do_check_free_chunk(m, q);
+ }
+ lastq = q;
+ q = next_chunk(q);
+ }
+ s = s->next;
+ }
+ }
+ return sum;
+}
+
+/* Check all properties of malloc_state. */
+static void do_check_malloc_state(mstate m) {
+ bindex_t i;
+ size_t total;
+ /* check bins */
+ for (i = 0; i < NSMALLBINS; ++i)
+ do_check_smallbin(m, i);
+ for (i = 0; i < NTREEBINS; ++i)
+ do_check_treebin(m, i);
+
+ if (m->dvsize != 0) { /* check dv chunk */
+ do_check_any_chunk(m, m->dv);
+ assert(m->dvsize == chunksize(m->dv));
+ assert(m->dvsize >= MIN_CHUNK_SIZE);
+ assert(bin_find(m, m->dv) == 0);
+ }
+
+ if (m->top != 0) { /* check top chunk */
+ do_check_top_chunk(m, m->top);
+ /*assert(m->topsize == chunksize(m->top)); redundant */
+ assert(m->topsize > 0);
+ assert(bin_find(m, m->top) == 0);
+ }
+
+ total = traverse_and_check(m);
+ assert(total <= m->footprint);
+ assert(m->footprint <= m->max_footprint);
+}
+#endif /* DEBUG */
+
+/* ----------------------------- statistics ------------------------------ */
+
+#if !NO_MALLINFO
+static struct mallinfo internal_mallinfo(mstate m) {
+ struct mallinfo nm = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+ if (!PREACTION(m)) {
+ check_malloc_state(m);
+ if (is_initialized(m)) {
+ size_t nfree = SIZE_T_ONE; /* top always free */
+ size_t mfree = m->topsize + TOP_FOOT_SIZE;
+ size_t sum = mfree;
+ msegmentptr s = &m->seg;
+ while (s != 0) {
+ mchunkptr q = align_as_chunk(s->base);
+ while (segment_holds(s, q) &&
+ q != m->top && q->head != FENCEPOST_HEAD) {
+ size_t sz = chunksize(q);
+ sum += sz;
+ if (!cinuse(q)) {
+ mfree += sz;
+ ++nfree;
+ }
+ q = next_chunk(q);
+ }
+ s = s->next;
+ }
+
+ nm.arena = sum;
+ nm.ordblks = nfree;
+ nm.hblkhd = m->footprint - sum;
+ nm.usmblks = m->max_footprint;
+ nm.uordblks = m->footprint - mfree;
+ nm.fordblks = mfree;
+ nm.keepcost = m->topsize;
+ }
+
+ POSTACTION(m);
+ }
+ return nm;
+}
+#endif /* !NO_MALLINFO */
+
+static void internal_malloc_stats(mstate m) {
+ if (!PREACTION(m)) {
+ size_t maxfp = 0;
+ size_t fp = 0;
+ size_t used = 0;
+ check_malloc_state(m);
+ if (is_initialized(m)) {
+ msegmentptr s = &m->seg;
+ maxfp = m->max_footprint;
+ fp = m->footprint;
+ used = fp - (m->topsize + TOP_FOOT_SIZE);
+
+ while (s != 0) {
+ mchunkptr q = align_as_chunk(s->base);
+ while (segment_holds(s, q) &&
+ q != m->top && q->head != FENCEPOST_HEAD) {
+ if (!cinuse(q))
+ used -= chunksize(q);
+ q = next_chunk(q);
+ }
+ s = s->next;
+ }
+ }
+
+ fprintf(stderr, "max system bytes = %10lu\n", (unsigned long)(maxfp));
+ fprintf(stderr, "system bytes = %10lu\n", (unsigned long)(fp));
+ fprintf(stderr, "in use bytes = %10lu\n", (unsigned long)(used));
+
+ POSTACTION(m);
+ }
+}
+
+/* ----------------------- Operations on smallbins ----------------------- */
+
+/*
+ Various forms of linking and unlinking are defined as macros. Even
+ the ones for trees, which are very long but have very short typical
+ paths. This is ugly but reduces reliance on inlining support of
+ compilers.
+*/
+
+/* Link a free chunk into a smallbin */
+#define insert_small_chunk(M, P, S) {\
+ bindex_t I = small_index(S);\
+ mchunkptr B = smallbin_at(M, I);\
+ mchunkptr F = B;\
+ assert(S >= MIN_CHUNK_SIZE);\
+ if (!smallmap_is_marked(M, I))\
+ mark_smallmap(M, I);\
+ else if (RTCHECK(ok_address(M, B->fd)))\
+ F = B->fd;\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ B->fd = P;\
+ F->bk = P;\
+ P->fd = F;\
+ P->bk = B;\
+}
+
+/* Unlink a chunk from a smallbin */
+#define unlink_small_chunk(M, P, S) {\
+ mchunkptr F = P->fd;\
+ mchunkptr B = P->bk;\
+ bindex_t I = small_index(S);\
+ assert(P != B);\
+ assert(P != F);\
+ assert(chunksize(P) == small_index2size(I));\
+ if (F == B)\
+ clear_smallmap(M, I);\
+ else if (RTCHECK((F == smallbin_at(M,I) || ok_address(M, F)) &&\
+ (B == smallbin_at(M,I) || ok_address(M, B)))) {\
+ F->bk = B;\
+ B->fd = F;\
+ }\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+}
+
+/* Unlink the first chunk from a smallbin */
+#define unlink_first_small_chunk(M, B, P, I) {\
+ mchunkptr F = P->fd;\
+ assert(P != B);\
+ assert(P != F);\
+ assert(chunksize(P) == small_index2size(I));\
+ if (B == F)\
+ clear_smallmap(M, I);\
+ else if (RTCHECK(ok_address(M, F))) {\
+ B->fd = F;\
+ F->bk = B;\
+ }\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+}
+
+/* Replace dv node, binning the old one */
+/* Used only when dvsize known to be small */
+#define replace_dv(M, P, S) {\
+ size_t DVS = M->dvsize;\
+ if (DVS != 0) {\
+ mchunkptr DV = M->dv;\
+ assert(is_small(DVS));\
+ insert_small_chunk(M, DV, DVS);\
+ }\
+ M->dvsize = S;\
+ M->dv = P;\
+}
+
+/* ------------------------- Operations on trees ------------------------- */
+
+/* Insert chunk into tree */
+#define insert_large_chunk(M, X, S) {\
+ tbinptr* H;\
+ bindex_t I;\
+ compute_tree_index(S, I);\
+ H = treebin_at(M, I);\
+ X->index = I;\
+ X->child[0] = X->child[1] = 0;\
+ if (!treemap_is_marked(M, I)) {\
+ mark_treemap(M, I);\
+ *H = X;\
+ X->parent = (tchunkptr)H;\
+ X->fd = X->bk = X;\
+ }\
+ else {\
+ tchunkptr T = *H;\
+ size_t K = S << leftshift_for_tree_index(I);\
+ for (;;) {\
+ if (chunksize(T) != S) {\
+ tchunkptr* C = &(T->child[(K >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1]);\
+ K <<= 1;\
+ if (*C != 0)\
+ T = *C;\
+ else if (RTCHECK(ok_address(M, C))) {\
+ *C = X;\
+ X->parent = T;\
+ X->fd = X->bk = X;\
+ break;\
+ }\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ break;\
+ }\
+ }\
+ else {\
+ tchunkptr F = T->fd;\
+ if (RTCHECK(ok_address(M, T) && ok_address(M, F))) {\
+ T->fd = F->bk = X;\
+ X->fd = F;\
+ X->bk = T;\
+ X->parent = 0;\
+ break;\
+ }\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ break;\
+ }\
+ }\
+ }\
+ }\
+}
+
+/*
+ Unlink steps:
+
+ 1. If x is a chained node, unlink it from its same-sized fd/bk links
+ and choose its bk node as its replacement.
+ 2. If x was the last node of its size, but not a leaf node, it must
+ be replaced with a leaf node (not merely one with an open left or
+ right), to make sure that lefts and rights of descendents
+ correspond properly to bit masks. We use the rightmost descendent
+ of x. We could use any other leaf, but this is easy to locate and
+ tends to counteract removal of leftmosts elsewhere, and so keeps
+ paths shorter than minimally guaranteed. This doesn't loop much
+ because on average a node in a tree is near the bottom.
+ 3. If x is the base of a chain (i.e., has parent links) relink
+ x's parent and children to x's replacement (or null if none).
+*/
+
+#define unlink_large_chunk(M, X) {\
+ tchunkptr XP = X->parent;\
+ tchunkptr R;\
+ if (X->bk != X) {\
+ tchunkptr F = X->fd;\
+ R = X->bk;\
+ if (RTCHECK(ok_address(M, F))) {\
+ F->bk = R;\
+ R->fd = F;\
+ }\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ }\
+ else {\
+ tchunkptr* RP;\
+ if (((R = *(RP = &(X->child[1]))) != 0) ||\
+ ((R = *(RP = &(X->child[0]))) != 0)) {\
+ tchunkptr* CP;\
+ while ((*(CP = &(R->child[1])) != 0) ||\
+ (*(CP = &(R->child[0])) != 0)) {\
+ R = *(RP = CP);\
+ }\
+ if (RTCHECK(ok_address(M, RP)))\
+ *RP = 0;\
+ else {\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ }\
+ }\
+ if (XP != 0) {\
+ tbinptr* H = treebin_at(M, X->index);\
+ if (X == *H) {\
+ if ((*H = R) == 0) \
+ clear_treemap(M, X->index);\
+ }\
+ else if (RTCHECK(ok_address(M, XP))) {\
+ if (XP->child[0] == X) \
+ XP->child[0] = R;\
+ else \
+ XP->child[1] = R;\
+ }\
+ else\
+ CORRUPTION_ERROR_ACTION(M);\
+ if (R != 0) {\
+ if (RTCHECK(ok_address(M, R))) {\
+ tchunkptr C0, C1;\
+ R->parent = XP;\
+ if ((C0 = X->child[0]) != 0) {\
+ if (RTCHECK(ok_address(M, C0))) {\
+ R->child[0] = C0;\
+ C0->parent = R;\
+ }\
+ else\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ if ((C1 = X->child[1]) != 0) {\
+ if (RTCHECK(ok_address(M, C1))) {\
+ R->child[1] = C1;\
+ C1->parent = R;\
+ }\
+ else\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ }\
+ else\
+ CORRUPTION_ERROR_ACTION(M);\
+ }\
+ }\
+}
+
+/* Relays to large vs small bin operations */
+
+#define insert_chunk(M, P, S)\
+ if (is_small(S)) insert_small_chunk(M, P, S)\
+ else { tchunkptr TP = (tchunkptr)(P); insert_large_chunk(M, TP, S); }
+
+#define unlink_chunk(M, P, S)\
+ if (is_small(S)) unlink_small_chunk(M, P, S)\
+ else { tchunkptr TP = (tchunkptr)(P); unlink_large_chunk(M, TP); }
+
+
+/* Relays to internal calls to malloc/free from realloc, memalign etc */
+
+#if ONLY_MSPACES
+#define internal_malloc(m, b) mspace_malloc(m, b)
+#define internal_free(m, mem) mspace_free(m,mem);
+#else /* ONLY_MSPACES */
+#if MSPACES
+#define internal_malloc(m, b)\
+ (m == gm)? dlmalloc(b) : mspace_malloc(m, b)
+#define internal_free(m, mem)\
+ if (m == gm) dlfree(mem); else mspace_free(m,mem);
+#else /* MSPACES */
+#define internal_malloc(m, b) dlmalloc(b)
+#define internal_free(m, mem) dlfree(mem)
+#endif /* MSPACES */
+#endif /* ONLY_MSPACES */
+
+/* ----------------------- Direct-mmapping chunks ----------------------- */
+
+/*
+ Directly mmapped chunks are set up with an offset to the start of
+ the mmapped region stored in the prev_foot field of the chunk. This
+ allows reconstruction of the required argument to MUNMAP when freed,
+ and also allows adjustment of the returned chunk to meet alignment
+ requirements (especially in memalign). There is also enough space
+ allocated to hold a fake next chunk of size SIZE_T_SIZE to maintain
+ the PINUSE bit so frees can be checked.
+*/
+
+/* Malloc using mmap */
+static void* mmap_alloc(mstate m, size_t nb) {
+ size_t mmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
+ if (mmsize > nb) { /* Check for wrap around 0 */
+ char* mm = (char*)(DIRECT_MMAP(mmsize));
+ if (mm != CMFAIL) {
+ size_t offset = align_offset(chunk2mem(mm));
+ size_t psize = mmsize - offset - MMAP_FOOT_PAD;
+ mchunkptr p = (mchunkptr)(mm + offset);
+ p->prev_foot = offset | IS_MMAPPED_BIT;
+ (p)->head = (psize|CINUSE_BIT);
+ mark_inuse_foot(m, p, psize);
+ chunk_plus_offset(p, psize)->head = FENCEPOST_HEAD;
+ chunk_plus_offset(p, psize+SIZE_T_SIZE)->head = 0;
+
+ if (mm < m->least_addr)
+ m->least_addr = mm;
+ if ((m->footprint += mmsize) > m->max_footprint)
+ m->max_footprint = m->footprint;
+ assert(is_aligned(chunk2mem(p)));
+ check_mmapped_chunk(m, p);
+ return chunk2mem(p);
+ }
+ }
+ return 0;
+}
+
+/* Realloc using mmap */
+static mchunkptr mmap_resize(mstate m, mchunkptr oldp, size_t nb) {
+ size_t oldsize = chunksize(oldp);
+ if (is_small(nb)) /* Can't shrink mmap regions below small size */
+ return 0;
+ /* Keep old chunk if big enough but not too big */
+ if (oldsize >= nb + SIZE_T_SIZE &&
+ (oldsize - nb) <= (mparams.granularity << 1))
+ return oldp;
+ else {
+ size_t offset = oldp->prev_foot & ~IS_MMAPPED_BIT;
+ size_t oldmmsize = oldsize + offset + MMAP_FOOT_PAD;
+ size_t newmmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
+ char* cp = (char*)CALL_MREMAP((char*)oldp - offset,
+ oldmmsize, newmmsize, 1);
+ if (cp != CMFAIL) {
+ mchunkptr newp = (mchunkptr)(cp + offset);
+ size_t psize = newmmsize - offset - MMAP_FOOT_PAD;
+ newp->head = (psize|CINUSE_BIT);
+ mark_inuse_foot(m, newp, psize);
+ chunk_plus_offset(newp, psize)->head = FENCEPOST_HEAD;
+ chunk_plus_offset(newp, psize+SIZE_T_SIZE)->head = 0;
+
+ if (cp < m->least_addr)
+ m->least_addr = cp;
+ if ((m->footprint += newmmsize - oldmmsize) > m->max_footprint)
+ m->max_footprint = m->footprint;
+ check_mmapped_chunk(m, newp);
+ return newp;
+ }
+ }
+ return 0;
+}
+
+/* -------------------------- mspace management -------------------------- */
+
+/* Initialize top chunk and its size */
+static void init_top(mstate m, mchunkptr p, size_t psize) {
+ /* Ensure alignment */
+ size_t offset = align_offset(chunk2mem(p));
+ p = (mchunkptr)((char*)p + offset);
+ psize -= offset;
+
+ m->top = p;
+ m->topsize = psize;
+ p->head = psize | PINUSE_BIT;
+ /* set size of fake trailing chunk holding overhead space only once */
+ chunk_plus_offset(p, psize)->head = TOP_FOOT_SIZE;
+ m->trim_check = mparams.trim_threshold; /* reset on each update */
+}
+
+/* Initialize bins for a new mstate that is otherwise zeroed out */
+static void init_bins(mstate m) {
+ /* Establish circular links for smallbins */
+ bindex_t i;
+ for (i = 0; i < NSMALLBINS; ++i) {
+ sbinptr bin = smallbin_at(m,i);
+ bin->fd = bin->bk = bin;
+ }
+}
+
+#if PROCEED_ON_ERROR
+
+/* default corruption action */
+static void reset_on_error(mstate m) {
+ int i;
+ ++malloc_corruption_error_count;
+ /* Reinitialize fields to forget about all memory */
+ m->smallbins = m->treebins = 0;
+ m->dvsize = m->topsize = 0;
+ m->seg.base = 0;
+ m->seg.size = 0;
+ m->seg.next = 0;
+ m->top = m->dv = 0;
+ for (i = 0; i < NTREEBINS; ++i)
+ *treebin_at(m, i) = 0;
+ init_bins(m);
+}
+#endif /* PROCEED_ON_ERROR */
+
+/* Allocate chunk and prepend remainder with chunk in successor base. */
+static void* prepend_alloc(mstate m, char* newbase, char* oldbase,
+ size_t nb) {
+ mchunkptr p = align_as_chunk(newbase);
+ mchunkptr oldfirst = align_as_chunk(oldbase);
+ size_t psize = (char*)oldfirst - (char*)p;
+ mchunkptr q = chunk_plus_offset(p, nb);
+ size_t qsize = psize - nb;
+ set_size_and_pinuse_of_inuse_chunk(m, p, nb);
+
+ assert((char*)oldfirst > (char*)q);
+ assert(pinuse(oldfirst));
+ assert(qsize >= MIN_CHUNK_SIZE);
+
+ /* consolidate remainder with first chunk of old base */
+ if (oldfirst == m->top) {
+ size_t tsize = m->topsize += qsize;
+ m->top = q;
+ q->head = tsize | PINUSE_BIT;
+ check_top_chunk(m, q);
+ }
+ else if (oldfirst == m->dv) {
+ size_t dsize = m->dvsize += qsize;
+ m->dv = q;
+ set_size_and_pinuse_of_free_chunk(q, dsize);
+ }
+ else {
+ if (!cinuse(oldfirst)) {
+ size_t nsize = chunksize(oldfirst);
+ unlink_chunk(m, oldfirst, nsize);
+ oldfirst = chunk_plus_offset(oldfirst, nsize);
+ qsize += nsize;
+ }
+ set_free_with_pinuse(q, qsize, oldfirst);
+ insert_chunk(m, q, qsize);
+ check_free_chunk(m, q);
+ }
+
+ check_malloced_chunk(m, chunk2mem(p), nb);
+ return chunk2mem(p);
+}
+
+/* Add a segment to hold a new noncontiguous region */
+static void add_segment(mstate m, char* tbase, size_t tsize, flag_t mmapped) {
+ /* Determine locations and sizes of segment, fenceposts, old top */
+ char* old_top = (char*)m->top;
+ msegmentptr oldsp = segment_holding(m, old_top);
+ char* old_end = oldsp->base + oldsp->size;
+ size_t ssize = pad_request(sizeof(struct malloc_segment));
+ char* rawsp = old_end - (ssize + FOUR_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
+ size_t offset = align_offset(chunk2mem(rawsp));
+ char* asp = rawsp + offset;
+ char* csp = (asp < (old_top + MIN_CHUNK_SIZE))? old_top : asp;
+ mchunkptr sp = (mchunkptr)csp;
+ msegmentptr ss = (msegmentptr)(chunk2mem(sp));
+ mchunkptr tnext = chunk_plus_offset(sp, ssize);
+ mchunkptr p = tnext;
+ int nfences = 0;
+
+ /* reset top to new space */
+ init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE);
+
+ /* Set up segment record */
+ assert(is_aligned(ss));
+ set_size_and_pinuse_of_inuse_chunk(m, sp, ssize);
+ *ss = m->seg; /* Push current record */
+ m->seg.base = tbase;
+ m->seg.size = tsize;
+ m->seg.sflags = mmapped;
+ m->seg.next = ss;
+
+ /* Insert trailing fenceposts */
+ for (;;) {
+ mchunkptr nextp = chunk_plus_offset(p, SIZE_T_SIZE);
+ p->head = FENCEPOST_HEAD;
+ ++nfences;
+ if ((char*)(&(nextp->head)) < old_end)
+ p = nextp;
+ else
+ break;
+ }
+ assert(nfences >= 2);
+
+ /* Insert the rest of old top into a bin as an ordinary free chunk */
+ if (csp != old_top) {
+ mchunkptr q = (mchunkptr)old_top;
+ size_t psize = csp - old_top;
+ mchunkptr tn = chunk_plus_offset(q, psize);
+ set_free_with_pinuse(q, psize, tn);
+ insert_chunk(m, q, psize);
+ }
+
+ check_top_chunk(m, m->top);
+}
+
+/* -------------------------- System allocation -------------------------- */
+
+/* Get memory from system using MORECORE or MMAP */
+static void* sys_alloc(mstate m, size_t nb) {
+ char* tbase = CMFAIL;
+ size_t tsize = 0;
+ flag_t mmap_flag = 0;
+
+ init_mparams();
+
+ /* Directly map large chunks */
+ if (use_mmap(m) && nb >= mparams.mmap_threshold) {
+ void* mem = mmap_alloc(m, nb);
+ if (mem != 0)
+ return mem;
+ }
+
+ /*
+ Try getting memory in any of three ways (in most-preferred to
+ least-preferred order):
+ 1. A call to MORECORE that can normally contiguously extend memory.
+ (disabled if not MORECORE_CONTIGUOUS or not HAVE_MORECORE or
+ or main space is mmapped or a previous contiguous call failed)
+ 2. A call to MMAP new space (disabled if not HAVE_MMAP).
+ Note that under the default settings, if MORECORE is unable to
+ fulfill a request, and HAVE_MMAP is true, then mmap is
+ used as a noncontiguous system allocator. This is a useful backup
+ strategy for systems with holes in address spaces -- in this case
+ sbrk cannot contiguously expand the heap, but mmap may be able to
+ find space.
+ 3. A call to MORECORE that cannot usually contiguously extend memory.
+ (disabled if not HAVE_MORECORE)
+ */
+
+ if (MORECORE_CONTIGUOUS && !use_noncontiguous(m)) {
+ char* br = CMFAIL;
+ msegmentptr ss = (m->top == 0)? 0 : segment_holding(m, (char*)m->top);
+ size_t asize = 0;
+ ACQUIRE_MORECORE_LOCK();
+
+ if (ss == 0) { /* First time through or recovery */
+ char* base = (char*)CALL_MORECORE(0);
+ if (base != CMFAIL) {
+ asize = granularity_align(nb + TOP_FOOT_SIZE + SIZE_T_ONE);
+ /* Adjust to end on a page boundary */
+ if (!is_page_aligned(base))
+ asize += (page_align((size_t)base) - (size_t)base);
+ /* Can't call MORECORE if size is negative when treated as signed */
+ if (asize < HALF_MAX_SIZE_T &&
+ (br = (char*)(CALL_MORECORE(asize))) == base) {
+ tbase = base;
+ tsize = asize;
+ }
+ }
+ }
+ else {
+ /* Subtract out existing available top space from MORECORE request. */
+ asize = granularity_align(nb - m->topsize + TOP_FOOT_SIZE + SIZE_T_ONE);
+ /* Use mem here only if it did continuously extend old space */
+ if (asize < HALF_MAX_SIZE_T &&
+ (br = (char*)(CALL_MORECORE(asize))) == ss->base+ss->size) {
+ tbase = br;
+ tsize = asize;
+ }
+ }
+
+ if (tbase == CMFAIL) { /* Cope with partial failure */
+ if (br != CMFAIL) { /* Try to use/extend the space we did get */
+ if (asize < HALF_MAX_SIZE_T &&
+ asize < nb + TOP_FOOT_SIZE + SIZE_T_ONE) {
+ size_t esize = granularity_align(nb + TOP_FOOT_SIZE + SIZE_T_ONE - asize);
+ if (esize < HALF_MAX_SIZE_T) {
+ char* end = (char*)CALL_MORECORE(esize);
+ if (end != CMFAIL)
+ asize += esize;
+ else { /* Can't use; try to release */
+ (void) CALL_MORECORE(-asize);
+ br = CMFAIL;
+ }
+ }
+ }
+ }
+ if (br != CMFAIL) { /* Use the space we did get */
+ tbase = br;
+ tsize = asize;
+ }
+ else
+ disable_contiguous(m); /* Don't try contiguous path in the future */
+ }
+
+ RELEASE_MORECORE_LOCK();
+ }
+
+ if (HAVE_MMAP && tbase == CMFAIL) { /* Try MMAP */
+ size_t req = nb + TOP_FOOT_SIZE + SIZE_T_ONE;
+ size_t rsize = granularity_align(req);
+ if (rsize > nb) { /* Fail if wraps around zero */
+ char* mp = (char*)(CALL_MMAP(rsize));
+ if (mp != CMFAIL) {
+ tbase = mp;
+ tsize = rsize;
+ mmap_flag = IS_MMAPPED_BIT;
+ }
+ }
+ }
+
+ if (HAVE_MORECORE && tbase == CMFAIL) { /* Try noncontiguous MORECORE */
+ size_t asize = granularity_align(nb + TOP_FOOT_SIZE + SIZE_T_ONE);
+ if (asize < HALF_MAX_SIZE_T) {
+ char* br = CMFAIL;
+ char* end = CMFAIL;
+ ACQUIRE_MORECORE_LOCK();
+ br = (char*)(CALL_MORECORE(asize));
+ end = (char*)(CALL_MORECORE(0));
+ RELEASE_MORECORE_LOCK();
+ if (br != CMFAIL && end != CMFAIL && br < end) {
+ size_t ssize = end - br;
+ if (ssize > nb + TOP_FOOT_SIZE) {
+ tbase = br;
+ tsize = ssize;
+ }
+ }
+ }
+ }
+
+ if (tbase != CMFAIL) {
+
+ if ((m->footprint += tsize) > m->max_footprint)
+ m->max_footprint = m->footprint;
+
+ if (!is_initialized(m)) { /* first-time initialization */
+ m->seg.base = m->least_addr = tbase;
+ m->seg.size = tsize;
+ m->seg.sflags = mmap_flag;
+ m->magic = mparams.magic;
+ m->release_checks = MAX_RELEASE_CHECK_RATE;
+ init_bins(m);
+#if !ONLY_MSPACES
+ if (is_global(m))
+ init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE);
+ else
+#endif
+ {
+ /* Offset top by embedded malloc_state */
+ mchunkptr mn = next_chunk(mem2chunk(m));
+ init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) -TOP_FOOT_SIZE);
+ }
+ }
+
+ else {
+ /* Try to merge with an existing segment */
+ msegmentptr sp = &m->seg;
+ /* Only consider most recent segment if traversal suppressed */
+ while (sp != 0 && tbase != sp->base + sp->size)
+ sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next;
+ if (sp != 0 &&
+ !is_extern_segment(sp) &&
+ (sp->sflags & IS_MMAPPED_BIT) == mmap_flag &&
+ segment_holds(sp, m->top)) { /* append */
+ sp->size += tsize;
+ init_top(m, m->top, m->topsize + tsize);
+ }
+ else {
+ if (tbase < m->least_addr)
+ m->least_addr = tbase;
+ sp = &m->seg;
+ while (sp != 0 && sp->base != tbase + tsize)
+ sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next;
+ if (sp != 0 &&
+ !is_extern_segment(sp) &&
+ (sp->sflags & IS_MMAPPED_BIT) == mmap_flag) {
+ char* oldbase = sp->base;
+ sp->base = tbase;
+ sp->size += tsize;
+ return prepend_alloc(m, tbase, oldbase, nb);
+ }
+ else
+ add_segment(m, tbase, tsize, mmap_flag);
+ }
+ }
+
+ if (nb < m->topsize) { /* Allocate from new or extended top space */
+ size_t rsize = m->topsize -= nb;
+ mchunkptr p = m->top;
+ mchunkptr r = m->top = chunk_plus_offset(p, nb);
+ r->head = rsize | PINUSE_BIT;
+ set_size_and_pinuse_of_inuse_chunk(m, p, nb);
+ check_top_chunk(m, m->top);
+ check_malloced_chunk(m, chunk2mem(p), nb);
+ return chunk2mem(p);
+ }
+ }
+
+ MALLOC_FAILURE_ACTION;
+ return 0;
+}
+
+/* ----------------------- system deallocation -------------------------- */
+
+/* Unmap and unlink any mmapped segments that don't contain used chunks */
+static size_t release_unused_segments(mstate m) {
+ size_t released = 0;
+ int nsegs = 0;
+ msegmentptr pred = &m->seg;
+ msegmentptr sp = pred->next;
+ while (sp != 0) {
+ char* base = sp->base;
+ size_t size = sp->size;
+ msegmentptr next = sp->next;
+ ++nsegs;
+ if (is_mmapped_segment(sp) && !is_extern_segment(sp)) {
+ mchunkptr p = align_as_chunk(base);
+ size_t psize = chunksize(p);
+ /* Can unmap if first chunk holds entire segment and not pinned */
+ if (!cinuse(p) && (char*)p + psize >= base + size - TOP_FOOT_SIZE) {
+ tchunkptr tp = (tchunkptr)p;
+ assert(segment_holds(sp, (char*)sp));
+ if (p == m->dv) {
+ m->dv = 0;
+ m->dvsize = 0;
+ }
+ else {
+ unlink_large_chunk(m, tp);
+ }
+ if (CALL_MUNMAP(base, size) == 0) {
+ released += size;
+ m->footprint -= size;
+ /* unlink obsoleted record */
+ sp = pred;
+ sp->next = next;
+ }
+ else { /* back out if cannot unmap */
+ insert_large_chunk(m, tp, psize);
+ }
+ }
+ }
+ if (NO_SEGMENT_TRAVERSAL) /* scan only first segment */
+ break;
+ pred = sp;
+ sp = next;
+ }
+ /* Reset check counter */
+ m->release_checks = ((nsegs > MAX_RELEASE_CHECK_RATE)?
+ nsegs : MAX_RELEASE_CHECK_RATE);
+ return released;
+}
+
+static int sys_trim(mstate m, size_t pad) {
+ size_t released = 0;
+ if (pad < MAX_REQUEST && is_initialized(m)) {
+ pad += TOP_FOOT_SIZE; /* ensure enough room for segment overhead */
+
+ if (m->topsize > pad) {
+ /* Shrink top space in granularity-size units, keeping at least one */
+ size_t unit = mparams.granularity;
+ size_t extra = ((m->topsize - pad + (unit - SIZE_T_ONE)) / unit -
+ SIZE_T_ONE) * unit;
+ msegmentptr sp = segment_holding(m, (char*)m->top);
+
+ if (!is_extern_segment(sp)) {
+ if (is_mmapped_segment(sp)) {
+ if (HAVE_MMAP &&
+ sp->size >= extra &&
+ !has_segment_link(m, sp)) { /* can't shrink if pinned */
+ size_t newsize = sp->size - extra;
+ /* Prefer mremap, fall back to munmap */
+ if ((CALL_MREMAP(sp->base, sp->size, newsize, 0) != MFAIL) ||
+ (CALL_MUNMAP(sp->base + newsize, extra) == 0)) {
+ released = extra;
+ }
+ }
+ }
+ else if (HAVE_MORECORE) {
+ if (extra >= HALF_MAX_SIZE_T) /* Avoid wrapping negative */
+ extra = (HALF_MAX_SIZE_T) + SIZE_T_ONE - unit;
+ ACQUIRE_MORECORE_LOCK();
+ {
+ /* Make sure end of memory is where we last set it. */
+ char* old_br = (char*)(CALL_MORECORE(0));
+ if (old_br == sp->base + sp->size) {
+ char* rel_br = (char*)(CALL_MORECORE(-extra));
+ char* new_br = (char*)(CALL_MORECORE(0));
+ if (rel_br != CMFAIL && new_br < old_br)
+ released = old_br - new_br;
+ }
+ }
+ RELEASE_MORECORE_LOCK();
+ }
+ }
+
+ if (released != 0) {
+ sp->size -= released;
+ m->footprint -= released;
+ init_top(m, m->top, m->topsize - released);
+ check_top_chunk(m, m->top);
+ }
+ }
+
+ /* Unmap any unused mmapped segments */
+ if (HAVE_MMAP)
+ released += release_unused_segments(m);
+
+ /* On failure, disable autotrim to avoid repeated failed future calls */
+ if (released == 0 && m->topsize > m->trim_check)
+ m->trim_check = MAX_SIZE_T;
+ }
+
+ return (released != 0)? 1 : 0;
+}
+
+/* ---------------------------- malloc support --------------------------- */
+
+/* allocate a large request from the best fitting chunk in a treebin */
+static void* tmalloc_large(mstate m, size_t nb) {
+ tchunkptr v = 0;
+ size_t rsize = -nb; /* Unsigned negation */
+ tchunkptr t;
+ bindex_t idx;
+ compute_tree_index(nb, idx);
+
+ if ((t = *treebin_at(m, idx)) != 0) {
+ /* Traverse tree for this bin looking for node with size == nb */
+ size_t sizebits = nb << leftshift_for_tree_index(idx);
+ tchunkptr rst = 0; /* The deepest untaken right subtree */
+ for (;;) {
+ tchunkptr rt;
+ size_t trem = chunksize(t) - nb;
+ if (trem < rsize) {
+ v = t;
+ if ((rsize = trem) == 0)
+ break;
+ }
+ rt = t->child[1];
+ t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1];
+ if (rt != 0 && rt != t)
+ rst = rt;
+ if (t == 0) {
+ t = rst; /* set t to least subtree holding sizes > nb */
+ break;
+ }
+ sizebits <<= 1;
+ }
+ }
+
+ if (t == 0 && v == 0) { /* set t to root of next non-empty treebin */
+ binmap_t leftbits = left_bits(idx2bit(idx)) & m->treemap;
+ if (leftbits != 0) {
+ bindex_t i;
+ binmap_t leastbit = least_bit(leftbits);
+ compute_bit2idx(leastbit, i);
+ t = *treebin_at(m, i);
+ }
+ }
+
+ while (t != 0) { /* find smallest of tree or subtree */
+ size_t trem = chunksize(t) - nb;
+ if (trem < rsize) {
+ rsize = trem;
+ v = t;
+ }
+ t = leftmost_child(t);
+ }
+
+ /* If dv is a better fit, return 0 so malloc will use it */
+ if (v != 0 && rsize < (size_t)(m->dvsize - nb)) {
+ if (RTCHECK(ok_address(m, v))) { /* split */
+ mchunkptr r = chunk_plus_offset(v, nb);
+ assert(chunksize(v) == rsize + nb);
+ if (RTCHECK(ok_next(v, r))) {
+ unlink_large_chunk(m, v);
+ if (rsize < MIN_CHUNK_SIZE)
+ set_inuse_and_pinuse(m, v, (rsize + nb));
+ else {
+ set_size_and_pinuse_of_inuse_chunk(m, v, nb);
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ insert_chunk(m, r, rsize);
+ }
+ return chunk2mem(v);
+ }
+ }
+ CORRUPTION_ERROR_ACTION(m);
+ }
+ return 0;
+}
+
+/* allocate a small request from the best fitting chunk in a treebin */
+static void* tmalloc_small(mstate m, size_t nb) {
+ tchunkptr t, v;
+ size_t rsize;
+ bindex_t i;
+ binmap_t leastbit = least_bit(m->treemap);
+ compute_bit2idx(leastbit, i);
+
+ v = t = *treebin_at(m, i);
+ rsize = chunksize(t) - nb;
+
+ while ((t = leftmost_child(t)) != 0) {
+ size_t trem = chunksize(t) - nb;
+ if (trem < rsize) {
+ rsize = trem;
+ v = t;
+ }
+ }
+
+ if (RTCHECK(ok_address(m, v))) {
+ mchunkptr r = chunk_plus_offset(v, nb);
+ assert(chunksize(v) == rsize + nb);
+ if (RTCHECK(ok_next(v, r))) {
+ unlink_large_chunk(m, v);
+ if (rsize < MIN_CHUNK_SIZE)
+ set_inuse_and_pinuse(m, v, (rsize + nb));
+ else {
+ set_size_and_pinuse_of_inuse_chunk(m, v, nb);
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ replace_dv(m, r, rsize);
+ }
+ return chunk2mem(v);
+ }
+ }
+
+ CORRUPTION_ERROR_ACTION(m);
+ return 0;
+}
+
+/* --------------------------- realloc support --------------------------- */
+
+static void* internal_realloc(mstate m, void* oldmem, size_t bytes) {
+ if (bytes >= MAX_REQUEST) {
+ MALLOC_FAILURE_ACTION;
+ return 0;
+ }
+ if (!PREACTION(m)) {
+ mchunkptr oldp = mem2chunk(oldmem);
+ size_t oldsize = chunksize(oldp);
+ mchunkptr next = chunk_plus_offset(oldp, oldsize);
+ mchunkptr newp = 0;
+ void* extra = 0;
+
+ /* Try to either shrink or extend into top. Else malloc-copy-free */
+
+ if (RTCHECK(ok_address(m, oldp) && ok_cinuse(oldp) &&
+ ok_next(oldp, next) && ok_pinuse(next))) {
+ size_t nb = request2size(bytes);
+ if (is_mmapped(oldp))
+ newp = mmap_resize(m, oldp, nb);
+ else if (oldsize >= nb) { /* already big enough */
+ size_t rsize = oldsize - nb;
+ newp = oldp;
+ if (rsize >= MIN_CHUNK_SIZE) {
+ mchunkptr remainder = chunk_plus_offset(newp, nb);
+ set_inuse(m, newp, nb);
+ set_inuse(m, remainder, rsize);
+ extra = chunk2mem(remainder);
+ }
+ }
+ else if (next == m->top && oldsize + m->topsize > nb) {
+ /* Expand into top */
+ size_t newsize = oldsize + m->topsize;
+ size_t newtopsize = newsize - nb;
+ mchunkptr newtop = chunk_plus_offset(oldp, nb);
+ set_inuse(m, oldp, nb);
+ newtop->head = newtopsize |PINUSE_BIT;
+ m->top = newtop;
+ m->topsize = newtopsize;
+ newp = oldp;
+ }
+ }
+ else {
+ USAGE_ERROR_ACTION(m, oldmem);
+ POSTACTION(m);
+ return 0;
+ }
+
+ POSTACTION(m);
+
+ if (newp != 0) {
+ if (extra != 0) {
+ internal_free(m, extra);
+ }
+ check_inuse_chunk(m, newp);
+ return chunk2mem(newp);
+ }
+ else {
+ void* newmem = internal_malloc(m, bytes);
+ if (newmem != 0) {
+ size_t oc = oldsize - overhead_for(oldp);
+ memcpy(newmem, oldmem, (oc < bytes)? oc : bytes);
+ internal_free(m, oldmem);
+ }
+ return newmem;
+ }
+ }
+ return 0;
+}
+
+/* --------------------------- memalign support -------------------------- */
+
+static void* internal_memalign(mstate m, size_t alignment, size_t bytes) {
+ if (alignment <= MALLOC_ALIGNMENT) /* Can just use malloc */
+ return internal_malloc(m, bytes);
+ if (alignment < MIN_CHUNK_SIZE) /* must be at least a minimum chunk size */
+ alignment = MIN_CHUNK_SIZE;
+ if ((alignment & (alignment-SIZE_T_ONE)) != 0) {/* Ensure a power of 2 */
+ size_t a = MALLOC_ALIGNMENT << 1;
+ while (a < alignment) a <<= 1;
+ alignment = a;
+ }
+
+ if (bytes >= MAX_REQUEST - alignment) {
+ if (m != 0) { /* Test isn't needed but avoids compiler warning */
+ MALLOC_FAILURE_ACTION;
+ }
+ }
+ else {
+ size_t nb = request2size(bytes);
+ size_t req = nb + alignment + MIN_CHUNK_SIZE - CHUNK_OVERHEAD;
+ char* mem = (char*)internal_malloc(m, req);
+ if (mem != 0) {
+ void* leader = 0;
+ void* trailer = 0;
+ mchunkptr p = mem2chunk(mem);
+
+ if (PREACTION(m)) return 0;
+ if ((((size_t)(mem)) % alignment) != 0) { /* misaligned */
+ /*
+ Find an aligned spot inside chunk. Since we need to give
+ back leading space in a chunk of at least MIN_CHUNK_SIZE, if
+ the first calculation places us at a spot with less than
+ MIN_CHUNK_SIZE leader, we can move to the next aligned spot.
+ We've allocated enough total room so that this is always
+ possible.
+ */
+ char* br = (char*)mem2chunk((size_t)(((size_t)(mem +
+ alignment -
+ SIZE_T_ONE)) &
+ -alignment));
+ char* pos = ((size_t)(br - (char*)(p)) >= MIN_CHUNK_SIZE)?
+ br : br+alignment;
+ mchunkptr newp = (mchunkptr)pos;
+ size_t leadsize = pos - (char*)(p);
+ size_t newsize = chunksize(p) - leadsize;
+
+ if (is_mmapped(p)) { /* For mmapped chunks, just adjust offset */
+ newp->prev_foot = p->prev_foot + leadsize;
+ newp->head = (newsize|CINUSE_BIT);
+ }
+ else { /* Otherwise, give back leader, use the rest */
+ set_inuse(m, newp, newsize);
+ set_inuse(m, p, leadsize);
+ leader = chunk2mem(p);
+ }
+ p = newp;
+ }
+
+ /* Give back spare room at the end */
+ if (!is_mmapped(p)) {
+ size_t size = chunksize(p);
+ if (size > nb + MIN_CHUNK_SIZE) {
+ size_t remainder_size = size - nb;
+ mchunkptr remainder = chunk_plus_offset(p, nb);
+ set_inuse(m, p, nb);
+ set_inuse(m, remainder, remainder_size);
+ trailer = chunk2mem(remainder);
+ }
+ }
+
+ assert (chunksize(p) >= nb);
+ assert((((size_t)(chunk2mem(p))) % alignment) == 0);
+ check_inuse_chunk(m, p);
+ POSTACTION(m);
+ if (leader != 0) {
+ internal_free(m, leader);
+ }
+ if (trailer != 0) {
+ internal_free(m, trailer);
+ }
+ return chunk2mem(p);
+ }
+ }
+ return 0;
+}
+
+/* ------------------------ comalloc/coalloc support --------------------- */
+
+static void** ialloc(mstate m,
+ size_t n_elements,
+ size_t* sizes,
+ int opts,
+ void* chunks[]) {
+ /*
+ This provides common support for independent_X routines, handling
+ all of the combinations that can result.
+
+ The opts arg has:
+ bit 0 set if all elements are same size (using sizes[0])
+ bit 1 set if elements should be zeroed
+ */
+
+ size_t element_size; /* chunksize of each element, if all same */
+ size_t contents_size; /* total size of elements */
+ size_t array_size; /* request size of pointer array */
+ void* mem; /* malloced aggregate space */
+ mchunkptr p; /* corresponding chunk */
+ size_t remainder_size; /* remaining bytes while splitting */
+ void** marray; /* either "chunks" or malloced ptr array */
+ mchunkptr array_chunk; /* chunk for malloced ptr array */
+ flag_t was_enabled; /* to disable mmap */
+ size_t size;
+ size_t i;
+
+ /* compute array length, if needed */
+ if (chunks != 0) {
+ if (n_elements == 0)
+ return chunks; /* nothing to do */
+ marray = chunks;
+ array_size = 0;
+ }
+ else {
+ /* if empty req, must still return chunk representing empty array */
+ if (n_elements == 0)
+ return (void**)internal_malloc(m, 0);
+ marray = 0;
+ array_size = request2size(n_elements * (sizeof(void*)));
+ }
+
+ /* compute total element size */
+ if (opts & 0x1) { /* all-same-size */
+ element_size = request2size(*sizes);
+ contents_size = n_elements * element_size;
+ }
+ else { /* add up all the sizes */
+ element_size = 0;
+ contents_size = 0;
+ for (i = 0; i != n_elements; ++i)
+ contents_size += request2size(sizes[i]);
+ }
+
+ size = contents_size + array_size;
+
+ /*
+ Allocate the aggregate chunk. First disable direct-mmapping so
+ malloc won't use it, since we would not be able to later
+ free/realloc space internal to a segregated mmap region.
+ */
+ was_enabled = use_mmap(m);
+ disable_mmap(m);
+ mem = internal_malloc(m, size - CHUNK_OVERHEAD);
+ if (was_enabled)
+ enable_mmap(m);
+ if (mem == 0)
+ return 0;
+
+ if (PREACTION(m)) return 0;
+ p = mem2chunk(mem);
+ remainder_size = chunksize(p);
+
+ assert(!is_mmapped(p));
+
+ if (opts & 0x2) { /* optionally clear the elements */
+ memset((size_t*)mem, 0, remainder_size - SIZE_T_SIZE - array_size);
+ }
+
+ /* If not provided, allocate the pointer array as final part of chunk */
+ if (marray == 0) {
+ size_t array_chunk_size;
+ array_chunk = chunk_plus_offset(p, contents_size);
+ array_chunk_size = remainder_size - contents_size;
+ marray = (void**) (chunk2mem(array_chunk));
+ set_size_and_pinuse_of_inuse_chunk(m, array_chunk, array_chunk_size);
+ remainder_size = contents_size;
+ }
+
+ /* split out elements */
+ for (i = 0; ; ++i) {
+ marray[i] = chunk2mem(p);
+ if (i != n_elements-1) {
+ if (element_size != 0)
+ size = element_size;
+ else
+ size = request2size(sizes[i]);
+ remainder_size -= size;
+ set_size_and_pinuse_of_inuse_chunk(m, p, size);
+ p = chunk_plus_offset(p, size);
+ }
+ else { /* the final element absorbs any overallocation slop */
+ set_size_and_pinuse_of_inuse_chunk(m, p, remainder_size);
+ break;
+ }
+ }
+
+#if DEBUG
+ if (marray != chunks) {
+ /* final element must have exactly exhausted chunk */
+ if (element_size != 0) {
+ assert(remainder_size == element_size);
+ }
+ else {
+ assert(remainder_size == request2size(sizes[i]));
+ }
+ check_inuse_chunk(m, mem2chunk(marray));
+ }
+ for (i = 0; i != n_elements; ++i)
+ check_inuse_chunk(m, mem2chunk(marray[i]));
+
+#endif /* DEBUG */
+
+ POSTACTION(m);
+ return marray;
+}
+
+
+/* -------------------------- public routines ---------------------------- */
+
+#if !ONLY_MSPACES
+
+void* dlmalloc(size_t bytes) {
+ /*
+ Basic algorithm:
+ If a small request (< 256 bytes minus per-chunk overhead):
+ 1. If one exists, use a remainderless chunk in associated smallbin.
+ (Remainderless means that there are too few excess bytes to
+ represent as a chunk.)
+ 2. If it is big enough, use the dv chunk, which is normally the
+ chunk adjacent to the one used for the most recent small request.
+ 3. If one exists, split the smallest available chunk in a bin,
+ saving remainder in dv.
+ 4. If it is big enough, use the top chunk.
+ 5. If available, get memory from system and use it
+ Otherwise, for a large request:
+ 1. Find the smallest available binned chunk that fits, and use it
+ if it is better fitting than dv chunk, splitting if necessary.
+ 2. If better fitting than any binned chunk, use the dv chunk.
+ 3. If it is big enough, use the top chunk.
+ 4. If request size >= mmap threshold, try to directly mmap this chunk.
+ 5. If available, get memory from system and use it
+
+ The ugly goto's here ensure that postaction occurs along all paths.
+ */
+
+ if (!PREACTION(gm)) {
+ void* mem;
+ size_t nb;
+ if (bytes <= MAX_SMALL_REQUEST) {
+ bindex_t idx;
+ binmap_t smallbits;
+ nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes);
+ idx = small_index(nb);
+ smallbits = gm->smallmap >> idx;
+
+ if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */
+ mchunkptr b, p;
+ idx += ~smallbits & 1; /* Uses next bin if idx empty */
+ b = smallbin_at(gm, idx);
+ p = b->fd;
+ assert(chunksize(p) == small_index2size(idx));
+ unlink_first_small_chunk(gm, b, p, idx);
+ set_inuse_and_pinuse(gm, p, small_index2size(idx));
+ mem = chunk2mem(p);
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+
+ else if (nb > gm->dvsize) {
+ if (smallbits != 0) { /* Use chunk in next nonempty smallbin */
+ mchunkptr b, p, r;
+ size_t rsize;
+ bindex_t i;
+ binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx));
+ binmap_t leastbit = least_bit(leftbits);
+ compute_bit2idx(leastbit, i);
+ b = smallbin_at(gm, i);
+ p = b->fd;
+ assert(chunksize(p) == small_index2size(i));
+ unlink_first_small_chunk(gm, b, p, i);
+ rsize = small_index2size(i) - nb;
+ /* Fit here cannot be remainderless if 4byte sizes */
+ if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE)
+ set_inuse_and_pinuse(gm, p, small_index2size(i));
+ else {
+ set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
+ r = chunk_plus_offset(p, nb);
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ replace_dv(gm, r, rsize);
+ }
+ mem = chunk2mem(p);
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+
+ else if (gm->treemap != 0 && (mem = tmalloc_small(gm, nb)) != 0) {
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+ }
+ }
+ else if (bytes >= MAX_REQUEST)
+ nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */
+ else {
+ nb = pad_request(bytes);
+ if (gm->treemap != 0 && (mem = tmalloc_large(gm, nb)) != 0) {
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+ }
+
+ if (nb <= gm->dvsize) {
+ size_t rsize = gm->dvsize - nb;
+ mchunkptr p = gm->dv;
+ if (rsize >= MIN_CHUNK_SIZE) { /* split dv */
+ mchunkptr r = gm->dv = chunk_plus_offset(p, nb);
+ gm->dvsize = rsize;
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
+ }
+ else { /* exhaust dv */
+ size_t dvs = gm->dvsize;
+ gm->dvsize = 0;
+ gm->dv = 0;
+ set_inuse_and_pinuse(gm, p, dvs);
+ }
+ mem = chunk2mem(p);
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+
+ else if (nb < gm->topsize) { /* Split top */
+ size_t rsize = gm->topsize -= nb;
+ mchunkptr p = gm->top;
+ mchunkptr r = gm->top = chunk_plus_offset(p, nb);
+ r->head = rsize | PINUSE_BIT;
+ set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
+ mem = chunk2mem(p);
+ check_top_chunk(gm, gm->top);
+ check_malloced_chunk(gm, mem, nb);
+ goto postaction;
+ }
+
+ mem = sys_alloc(gm, nb);
+
+ postaction:
+ POSTACTION(gm);
+ return mem;
+ }
+
+ return 0;
+}
+
+void dlfree(void* mem) {
+ /*
+ Consolidate freed chunks with preceeding or succeeding bordering
+ free chunks, if they exist, and then place in a bin. Intermixed
+ with special cases for top, dv, mmapped chunks, and usage errors.
+ */
+
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+#if FOOTERS
+ mstate fm = get_mstate_for(p);
+ if (!ok_magic(fm)) {
+ USAGE_ERROR_ACTION(fm, p);
+ return;
+ }
+#else /* FOOTERS */
+#define fm gm
+#endif /* FOOTERS */
+ if (!PREACTION(fm)) {
+ check_inuse_chunk(fm, p);
+ if (RTCHECK(ok_address(fm, p) && ok_cinuse(p))) {
+ size_t psize = chunksize(p);
+ mchunkptr next = chunk_plus_offset(p, psize);
+ if (!pinuse(p)) {
+ size_t prevsize = p->prev_foot;
+ if ((prevsize & IS_MMAPPED_BIT) != 0) {
+ prevsize &= ~IS_MMAPPED_BIT;
+ psize += prevsize + MMAP_FOOT_PAD;
+ if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
+ fm->footprint -= psize;
+ goto postaction;
+ }
+ else {
+ mchunkptr prev = chunk_minus_offset(p, prevsize);
+ psize += prevsize;
+ p = prev;
+ if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */
+ if (p != fm->dv) {
+ unlink_chunk(fm, p, prevsize);
+ }
+ else if ((next->head & INUSE_BITS) == INUSE_BITS) {
+ fm->dvsize = psize;
+ set_free_with_pinuse(p, psize, next);
+ goto postaction;
+ }
+ }
+ else
+ goto erroraction;
+ }
+ }
+
+ if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) {
+ if (!cinuse(next)) { /* consolidate forward */
+ if (next == fm->top) {
+ size_t tsize = fm->topsize += psize;
+ fm->top = p;
+ p->head = tsize | PINUSE_BIT;
+ if (p == fm->dv) {
+ fm->dv = 0;
+ fm->dvsize = 0;
+ }
+ if (should_trim(fm, tsize))
+ sys_trim(fm, 0);
+ goto postaction;
+ }
+ else if (next == fm->dv) {
+ size_t dsize = fm->dvsize += psize;
+ fm->dv = p;
+ set_size_and_pinuse_of_free_chunk(p, dsize);
+ goto postaction;
+ }
+ else {
+ size_t nsize = chunksize(next);
+ psize += nsize;
+ unlink_chunk(fm, next, nsize);
+ set_size_and_pinuse_of_free_chunk(p, psize);
+ if (p == fm->dv) {
+ fm->dvsize = psize;
+ goto postaction;
+ }
+ }
+ }
+ else
+ set_free_with_pinuse(p, psize, next);
+
+ if (is_small(psize)) {
+ insert_small_chunk(fm, p, psize);
+ check_free_chunk(fm, p);
+ }
+ else {
+ tchunkptr tp = (tchunkptr)p;
+ insert_large_chunk(fm, tp, psize);
+ check_free_chunk(fm, p);
+ if (--fm->release_checks == 0)
+ release_unused_segments(fm);
+ }
+ goto postaction;
+ }
+ }
+ erroraction:
+ USAGE_ERROR_ACTION(fm, p);
+ postaction:
+ POSTACTION(fm);
+ }
+ }
+#if !FOOTERS
+#undef fm
+#endif /* FOOTERS */
+}
+
+void* dlcalloc(size_t n_elements, size_t elem_size) {
+ void* mem;
+ size_t req = 0;
+ if (n_elements != 0) {
+ req = n_elements * elem_size;
+ if (((n_elements | elem_size) & ~(size_t)0xffff) &&
+ (req / n_elements != elem_size))
+ req = MAX_SIZE_T; /* force downstream failure on overflow */
+ }
+ mem = dlmalloc(req);
+ if (mem != 0 && calloc_must_clear(mem2chunk(mem)))
+ memset(mem, 0, req);
+ return mem;
+}
+
+void* dlrealloc(void* oldmem, size_t bytes) {
+ if (oldmem == 0)
+ return dlmalloc(bytes);
+#ifdef REALLOC_ZERO_BYTES_FREES
+ if (bytes == 0) {
+ dlfree(oldmem);
+ return 0;
+ }
+#endif /* REALLOC_ZERO_BYTES_FREES */
+ else {
+#if ! FOOTERS
+ mstate m = gm;
+#else /* FOOTERS */
+ mstate m = get_mstate_for(mem2chunk(oldmem));
+ if (!ok_magic(m)) {
+ USAGE_ERROR_ACTION(m, oldmem);
+ return 0;
+ }
+#endif /* FOOTERS */
+ return internal_realloc(m, oldmem, bytes);
+ }
+}
+
+void* dlmemalign(size_t alignment, size_t bytes) {
+ return internal_memalign(gm, alignment, bytes);
+}
+
+void** dlindependent_calloc(size_t n_elements, size_t elem_size,
+ void* chunks[]) {
+ size_t sz = elem_size; /* serves as 1-element array */
+ return ialloc(gm, n_elements, &sz, 3, chunks);
+}
+
+void** dlindependent_comalloc(size_t n_elements, size_t sizes[],
+ void* chunks[]) {
+ return ialloc(gm, n_elements, sizes, 0, chunks);
+}
+
+void* dlvalloc(size_t bytes) {
+ size_t pagesz;
+ init_mparams();
+ pagesz = mparams.page_size;
+ return dlmemalign(pagesz, bytes);
+}
+
+void* dlpvalloc(size_t bytes) {
+ size_t pagesz;
+ init_mparams();
+ pagesz = mparams.page_size;
+ return dlmemalign(pagesz, (bytes + pagesz - SIZE_T_ONE) & ~(pagesz - SIZE_T_ONE));
+}
+
+int dlmalloc_trim(size_t pad) {
+ int result = 0;
+ if (!PREACTION(gm)) {
+ result = sys_trim(gm, pad);
+ POSTACTION(gm);
+ }
+ return result;
+}
+
+size_t dlmalloc_footprint(void) {
+ return gm->footprint;
+}
+
+size_t dlmalloc_max_footprint(void) {
+ return gm->max_footprint;
+}
+
+#if !NO_MALLINFO
+struct mallinfo dlmallinfo(void) {
+ return internal_mallinfo(gm);
+}
+#endif /* NO_MALLINFO */
+
+void dlmalloc_stats() {
+ internal_malloc_stats(gm);
+}
+
+size_t dlmalloc_usable_size(void* mem) {
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+ if (cinuse(p))
+ return chunksize(p) - overhead_for(p);
+ }
+ return 0;
+}
+
+int dlmallopt(int param_number, int value) {
+ return change_mparam(param_number, value);
+}
+
+#endif /* !ONLY_MSPACES */
+
+/* ----------------------------- user mspaces ---------------------------- */
+
+#if MSPACES
+
+static mstate init_user_mstate(char* tbase, size_t tsize) {
+ size_t msize = pad_request(sizeof(struct malloc_state));
+ mchunkptr mn;
+ mchunkptr msp = align_as_chunk(tbase);
+ mstate m = (mstate)(chunk2mem(msp));
+ memset(m, 0, msize);
+ INITIAL_LOCK(&m->mutex);
+ msp->head = (msize|PINUSE_BIT|CINUSE_BIT);
+ m->seg.base = m->least_addr = tbase;
+ m->seg.size = m->footprint = m->max_footprint = tsize;
+ m->magic = mparams.magic;
+ m->release_checks = MAX_RELEASE_CHECK_RATE;
+ m->mflags = mparams.default_mflags;
+ m->extp = 0;
+ m->exts = 0;
+ disable_contiguous(m);
+ init_bins(m);
+ mn = next_chunk(mem2chunk(m));
+ init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) - TOP_FOOT_SIZE);
+ check_top_chunk(m, m->top);
+ return m;
+}
+
+mspace create_mspace(size_t capacity, int locked) {
+ mstate m = 0;
+ size_t msize = pad_request(sizeof(struct malloc_state));
+ init_mparams(); /* Ensure pagesize etc initialized */
+
+ if (capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) {
+ size_t rs = ((capacity == 0)? mparams.granularity :
+ (capacity + TOP_FOOT_SIZE + msize));
+ size_t tsize = granularity_align(rs);
+ char* tbase = (char*)(CALL_MMAP(tsize));
+ if (tbase != CMFAIL) {
+ m = init_user_mstate(tbase, tsize);
+ m->seg.sflags = IS_MMAPPED_BIT;
+ set_lock(m, locked);
+ }
+ }
+ return (mspace)m;
+}
+
+mspace create_mspace_with_base(void* base, size_t capacity, int locked) {
+ mstate m = 0;
+ size_t msize = pad_request(sizeof(struct malloc_state));
+ init_mparams(); /* Ensure pagesize etc initialized */
+
+ if (capacity > msize + TOP_FOOT_SIZE &&
+ capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) {
+ m = init_user_mstate((char*)base, capacity);
+ m->seg.sflags = EXTERN_BIT;
+ set_lock(m, locked);
+ }
+ return (mspace)m;
+}
+
+size_t destroy_mspace(mspace msp) {
+ size_t freed = 0;
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ msegmentptr sp = &ms->seg;
+ while (sp != 0) {
+ char* base = sp->base;
+ size_t size = sp->size;
+ flag_t flag = sp->sflags;
+ sp = sp->next;
+ if ((flag & IS_MMAPPED_BIT) && !(flag & EXTERN_BIT) &&
+ CALL_MUNMAP(base, size) == 0)
+ freed += size;
+ }
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return freed;
+}
+
+/*
+ mspace versions of routines are near-clones of the global
+ versions. This is not so nice but better than the alternatives.
+*/
+
+
+void* mspace_malloc(mspace msp, size_t bytes) {
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ return 0;
+ }
+ if (!PREACTION(ms)) {
+ void* mem;
+ size_t nb;
+ if (bytes <= MAX_SMALL_REQUEST) {
+ bindex_t idx;
+ binmap_t smallbits;
+ nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes);
+ idx = small_index(nb);
+ smallbits = ms->smallmap >> idx;
+
+ if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */
+ mchunkptr b, p;
+ idx += ~smallbits & 1; /* Uses next bin if idx empty */
+ b = smallbin_at(ms, idx);
+ p = b->fd;
+ assert(chunksize(p) == small_index2size(idx));
+ unlink_first_small_chunk(ms, b, p, idx);
+ set_inuse_and_pinuse(ms, p, small_index2size(idx));
+ mem = chunk2mem(p);
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+
+ else if (nb > ms->dvsize) {
+ if (smallbits != 0) { /* Use chunk in next nonempty smallbin */
+ mchunkptr b, p, r;
+ size_t rsize;
+ bindex_t i;
+ binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx));
+ binmap_t leastbit = least_bit(leftbits);
+ compute_bit2idx(leastbit, i);
+ b = smallbin_at(ms, i);
+ p = b->fd;
+ assert(chunksize(p) == small_index2size(i));
+ unlink_first_small_chunk(ms, b, p, i);
+ rsize = small_index2size(i) - nb;
+ /* Fit here cannot be remainderless if 4byte sizes */
+ if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE)
+ set_inuse_and_pinuse(ms, p, small_index2size(i));
+ else {
+ set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
+ r = chunk_plus_offset(p, nb);
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ replace_dv(ms, r, rsize);
+ }
+ mem = chunk2mem(p);
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+
+ else if (ms->treemap != 0 && (mem = tmalloc_small(ms, nb)) != 0) {
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+ }
+ }
+ else if (bytes >= MAX_REQUEST)
+ nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */
+ else {
+ nb = pad_request(bytes);
+ if (ms->treemap != 0 && (mem = tmalloc_large(ms, nb)) != 0) {
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+ }
+
+ if (nb <= ms->dvsize) {
+ size_t rsize = ms->dvsize - nb;
+ mchunkptr p = ms->dv;
+ if (rsize >= MIN_CHUNK_SIZE) { /* split dv */
+ mchunkptr r = ms->dv = chunk_plus_offset(p, nb);
+ ms->dvsize = rsize;
+ set_size_and_pinuse_of_free_chunk(r, rsize);
+ set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
+ }
+ else { /* exhaust dv */
+ size_t dvs = ms->dvsize;
+ ms->dvsize = 0;
+ ms->dv = 0;
+ set_inuse_and_pinuse(ms, p, dvs);
+ }
+ mem = chunk2mem(p);
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+
+ else if (nb < ms->topsize) { /* Split top */
+ size_t rsize = ms->topsize -= nb;
+ mchunkptr p = ms->top;
+ mchunkptr r = ms->top = chunk_plus_offset(p, nb);
+ r->head = rsize | PINUSE_BIT;
+ set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
+ mem = chunk2mem(p);
+ check_top_chunk(ms, ms->top);
+ check_malloced_chunk(ms, mem, nb);
+ goto postaction;
+ }
+
+ mem = sys_alloc(ms, nb);
+
+ postaction:
+ POSTACTION(ms);
+ return mem;
+ }
+
+ return 0;
+}
+
+void mspace_free(mspace msp, void* mem) {
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+#if FOOTERS
+ mstate fm = get_mstate_for(p);
+#else /* FOOTERS */
+ mstate fm = (mstate)msp;
+#endif /* FOOTERS */
+ if (!ok_magic(fm)) {
+ USAGE_ERROR_ACTION(fm, p);
+ return;
+ }
+ if (!PREACTION(fm)) {
+ check_inuse_chunk(fm, p);
+ if (RTCHECK(ok_address(fm, p) && ok_cinuse(p))) {
+ size_t psize = chunksize(p);
+ mchunkptr next = chunk_plus_offset(p, psize);
+ if (!pinuse(p)) {
+ size_t prevsize = p->prev_foot;
+ if ((prevsize & IS_MMAPPED_BIT) != 0) {
+ prevsize &= ~IS_MMAPPED_BIT;
+ psize += prevsize + MMAP_FOOT_PAD;
+ if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
+ fm->footprint -= psize;
+ goto postaction;
+ }
+ else {
+ mchunkptr prev = chunk_minus_offset(p, prevsize);
+ psize += prevsize;
+ p = prev;
+ if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */
+ if (p != fm->dv) {
+ unlink_chunk(fm, p, prevsize);
+ }
+ else if ((next->head & INUSE_BITS) == INUSE_BITS) {
+ fm->dvsize = psize;
+ set_free_with_pinuse(p, psize, next);
+ goto postaction;
+ }
+ }
+ else
+ goto erroraction;
+ }
+ }
+
+ if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) {
+ if (!cinuse(next)) { /* consolidate forward */
+ if (next == fm->top) {
+ size_t tsize = fm->topsize += psize;
+ fm->top = p;
+ p->head = tsize | PINUSE_BIT;
+ if (p == fm->dv) {
+ fm->dv = 0;
+ fm->dvsize = 0;
+ }
+ if (should_trim(fm, tsize))
+ sys_trim(fm, 0);
+ goto postaction;
+ }
+ else if (next == fm->dv) {
+ size_t dsize = fm->dvsize += psize;
+ fm->dv = p;
+ set_size_and_pinuse_of_free_chunk(p, dsize);
+ goto postaction;
+ }
+ else {
+ size_t nsize = chunksize(next);
+ psize += nsize;
+ unlink_chunk(fm, next, nsize);
+ set_size_and_pinuse_of_free_chunk(p, psize);
+ if (p == fm->dv) {
+ fm->dvsize = psize;
+ goto postaction;
+ }
+ }
+ }
+ else
+ set_free_with_pinuse(p, psize, next);
+
+ if (is_small(psize)) {
+ insert_small_chunk(fm, p, psize);
+ check_free_chunk(fm, p);
+ }
+ else {
+ tchunkptr tp = (tchunkptr)p;
+ insert_large_chunk(fm, tp, psize);
+ check_free_chunk(fm, p);
+ if (--fm->release_checks == 0)
+ release_unused_segments(fm);
+ }
+ goto postaction;
+ }
+ }
+ erroraction:
+ USAGE_ERROR_ACTION(fm, p);
+ postaction:
+ POSTACTION(fm);
+ }
+ }
+}
+
+void* mspace_calloc(mspace msp, size_t n_elements, size_t elem_size) {
+ void* mem;
+ size_t req = 0;
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ return 0;
+ }
+ if (n_elements != 0) {
+ req = n_elements * elem_size;
+ if (((n_elements | elem_size) & ~(size_t)0xffff) &&
+ (req / n_elements != elem_size))
+ req = MAX_SIZE_T; /* force downstream failure on overflow */
+ }
+ mem = internal_malloc(ms, req);
+ if (mem != 0 && calloc_must_clear(mem2chunk(mem)))
+ memset(mem, 0, req);
+ return mem;
+}
+
+void* mspace_realloc(mspace msp, void* oldmem, size_t bytes) {
+ if (oldmem == 0)
+ return mspace_malloc(msp, bytes);
+#ifdef REALLOC_ZERO_BYTES_FREES
+ if (bytes == 0) {
+ mspace_free(msp, oldmem);
+ return 0;
+ }
+#endif /* REALLOC_ZERO_BYTES_FREES */
+ else {
+#if FOOTERS
+ mchunkptr p = mem2chunk(oldmem);
+ mstate ms = get_mstate_for(p);
+#else /* FOOTERS */
+ mstate ms = (mstate)msp;
+#endif /* FOOTERS */
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ return 0;
+ }
+ return internal_realloc(ms, oldmem, bytes);
+ }
+}
+
+void* mspace_memalign(mspace msp, size_t alignment, size_t bytes) {
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ return 0;
+ }
+ return internal_memalign(ms, alignment, bytes);
+}
+
+void** mspace_independent_calloc(mspace msp, size_t n_elements,
+ size_t elem_size, void* chunks[]) {
+ size_t sz = elem_size; /* serves as 1-element array */
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ return 0;
+ }
+ return ialloc(ms, n_elements, &sz, 3, chunks);
+}
+
+void** mspace_independent_comalloc(mspace msp, size_t n_elements,
+ size_t sizes[], void* chunks[]) {
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ return 0;
+ }
+ return ialloc(ms, n_elements, sizes, 0, chunks);
+}
+
+int mspace_trim(mspace msp, size_t pad) {
+ int result = 0;
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ if (!PREACTION(ms)) {
+ result = sys_trim(ms, pad);
+ POSTACTION(ms);
+ }
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return result;
+}
+
+void mspace_malloc_stats(mspace msp) {
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ internal_malloc_stats(ms);
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+}
+
+size_t mspace_footprint(mspace msp) {
+ size_t result = 0;
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ result = ms->footprint;
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return result;
+}
+
+
+size_t mspace_max_footprint(mspace msp) {
+ size_t result = 0;
+ mstate ms = (mstate)msp;
+ if (ok_magic(ms)) {
+ result = ms->max_footprint;
+ }
+ else {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return result;
+}
+
+
+#if !NO_MALLINFO
+struct mallinfo mspace_mallinfo(mspace msp) {
+ mstate ms = (mstate)msp;
+ if (!ok_magic(ms)) {
+ USAGE_ERROR_ACTION(ms,ms);
+ }
+ return internal_mallinfo(ms);
+}
+#endif /* NO_MALLINFO */
+
+size_t mspace_usable_size(void* mem) {
+ if (mem != 0) {
+ mchunkptr p = mem2chunk(mem);
+ if (cinuse(p))
+ return chunksize(p) - overhead_for(p);
+ }
+ return 0;
+}
+
+int mspace_mallopt(int param_number, int value) {
+ return change_mparam(param_number, value);
+}
+
+#endif /* MSPACES */
+
+/* -------------------- Alternative MORECORE functions ------------------- */
+
+/*
+ Guidelines for creating a custom version of MORECORE:
+
+ * For best performance, MORECORE should allocate in multiples of pagesize.
+ * MORECORE may allocate more memory than requested. (Or even less,
+ but this will usually result in a malloc failure.)
+ * MORECORE must not allocate memory when given argument zero, but
+ instead return one past the end address of memory from previous
+ nonzero call.
+ * For best performance, consecutive calls to MORECORE with positive
+ arguments should return increasing addresses, indicating that
+ space has been contiguously extended.
+ * Even though consecutive calls to MORECORE need not return contiguous
+ addresses, it must be OK for malloc'ed chunks to span multiple
+ regions in those cases where they do happen to be contiguous.
+ * MORECORE need not handle negative arguments -- it may instead
+ just return MFAIL when given negative arguments.
+ Negative arguments are always multiples of pagesize. MORECORE
+ must not misinterpret negative args as large positive unsigned
+ args. You can suppress all such calls from even occurring by defining
+ MORECORE_CANNOT_TRIM,
+
+ As an example alternative MORECORE, here is a custom allocator
+ kindly contributed for pre-OSX macOS. It uses virtually but not
+ necessarily physically contiguous non-paged memory (locked in,
+ present and won't get swapped out). You can use it by uncommenting
+ this section, adding some #includes, and setting up the appropriate
+ defines above:
+
+ #define MORECORE osMoreCore
+
+ There is also a shutdown routine that should somehow be called for
+ cleanup upon program exit.
+
+ #define MAX_POOL_ENTRIES 100
+ #define MINIMUM_MORECORE_SIZE (64 * 1024U)
+ static int next_os_pool;
+ void *our_os_pools[MAX_POOL_ENTRIES];
+
+ void *osMoreCore(int size)
+ {
+ void *ptr = 0;
+ static void *sbrk_top = 0;
+
+ if (size > 0)
+ {
+ if (size < MINIMUM_MORECORE_SIZE)
+ size = MINIMUM_MORECORE_SIZE;
+ if (CurrentExecutionLevel() == kTaskLevel)
+ ptr = PoolAllocateResident(size + RM_PAGE_SIZE, 0);
+ if (ptr == 0)
+ {
+ return (void *) MFAIL;
+ }
+ // save ptrs so they can be freed during cleanup
+ our_os_pools[next_os_pool] = ptr;
+ next_os_pool++;
+ ptr = (void *) ((((size_t) ptr) + RM_PAGE_MASK) & ~RM_PAGE_MASK);
+ sbrk_top = (char *) ptr + size;
+ return ptr;
+ }
+ else if (size < 0)
+ {
+ // we don't currently support shrink behavior
+ return (void *) MFAIL;
+ }
+ else
+ {
+ return sbrk_top;
+ }
+ }
+
+ // cleanup any allocated memory pools
+ // called as last thing before shutting down driver
+
+ void osCleanupMem(void)
+ {
+ void **ptr;
+
+ for (ptr = our_os_pools; ptr < &our_os_pools[MAX_POOL_ENTRIES]; ptr++)
+ if (*ptr)
+ {
+ PoolDeallocate(*ptr);
+ *ptr = 0;
+ }
+ }
+
+*/
+
+
+/* -----------------------------------------------------------------------
+History:
+ V2.8.4 (not yet released)
+ * Fix bad error check in mspace_footprint
+ * Adaptations for ptmalloc, courtesy of Wolfram Gloger.
+ * Reentrant spin locks, courtesy of Earl Chew and others
+ * Win32 improvements, courtesy of Niall Douglas and Earl Chew
+ * Add NO_SEGMENT_TRAVERSAL and MAX_RELEASE_CHECK_RATE options
+ * Various small adjustments to reduce warnings on some compilers
+ * Extension hook in malloc_state
+
+ V2.8.3 Thu Sep 22 11:16:32 2005 Doug Lea (dl at gee)
+ * Add max_footprint functions
+ * Ensure all appropriate literals are size_t
+ * Fix conditional compilation problem for some #define settings
+ * Avoid concatenating segments with the one provided
+ in create_mspace_with_base
+ * Rename some variables to avoid compiler shadowing warnings
+ * Use explicit lock initialization.
+ * Better handling of sbrk interference.
+ * Simplify and fix segment insertion, trimming and mspace_destroy
+ * Reinstate REALLOC_ZERO_BYTES_FREES option from 2.7.x
+ * Thanks especially to Dennis Flanagan for help on these.
+
+ V2.8.2 Sun Jun 12 16:01:10 2005 Doug Lea (dl at gee)
+ * Fix memalign brace error.
+
+ V2.8.1 Wed Jun 8 16:11:46 2005 Doug Lea (dl at gee)
+ * Fix improper #endif nesting in C++
+ * Add explicit casts needed for C++
+
+ V2.8.0 Mon May 30 14:09:02 2005 Doug Lea (dl at gee)
+ * Use trees for large bins
+ * Support mspaces
+ * Use segments to unify sbrk-based and mmap-based system allocation,
+ removing need for emulation on most platforms without sbrk.
+ * Default safety checks
+ * Optional footer checks. Thanks to William Robertson for the idea.
+ * Internal code refactoring
+ * Incorporate suggestions and platform-specific changes.
+ Thanks to Dennis Flanagan, Colin Plumb, Niall Douglas,
+ Aaron Bachmann, Emery Berger, and others.
+ * Speed up non-fastbin processing enough to remove fastbins.
+ * Remove useless cfree() to avoid conflicts with other apps.
+ * Remove internal memcpy, memset. Compilers handle builtins better.
+ * Remove some options that no one ever used and rename others.
+
+ V2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (dl at gee)
+ * Fix malloc_state bitmap array misdeclaration
+
+ V2.7.1 Thu Jul 25 10:58:03 2002 Doug Lea (dl at gee)
+ * Allow tuning of FIRST_SORTED_BIN_SIZE
+ * Use PTR_UINT as type for all ptr->int casts. Thanks to John Belmonte.
+ * Better detection and support for non-contiguousness of MORECORE.
+ Thanks to Andreas Mueller, Conal Walsh, and Wolfram Gloger
+ * Bypass most of malloc if no frees. Thanks To Emery Berger.
+ * Fix freeing of old top non-contiguous chunk im sysmalloc.
+ * Raised default trim and map thresholds to 256K.
+ * Fix mmap-related #defines. Thanks to Lubos Lunak.
+ * Fix copy macros; added LACKS_FCNTL_H. Thanks to Neal Walfield.
+ * Branch-free bin calculation
+ * Default trim and mmap thresholds now 256K.
+
+ V2.7.0 Sun Mar 11 14:14:06 2001 Doug Lea (dl at gee)
+ * Introduce independent_comalloc and independent_calloc.
+ Thanks to Michael Pachos for motivation and help.
+ * Make optional .h file available
+ * Allow > 2GB requests on 32bit systems.
+ * new WIN32 sbrk, mmap, munmap, lock code from <Walter@GeNeSys-e.de>.
+ Thanks also to Andreas Mueller <a.mueller at paradatec.de>,
+ and Anonymous.
+ * Allow override of MALLOC_ALIGNMENT (Thanks to Ruud Waij for
+ helping test this.)
+ * memalign: check alignment arg
+ * realloc: don't try to shift chunks backwards, since this
+ leads to more fragmentation in some programs and doesn't
+ seem to help in any others.
+ * Collect all cases in malloc requiring system memory into sysmalloc
+ * Use mmap as backup to sbrk
+ * Place all internal state in malloc_state
+ * Introduce fastbins (although similar to 2.5.1)
+ * Many minor tunings and cosmetic improvements
+ * Introduce USE_PUBLIC_MALLOC_WRAPPERS, USE_MALLOC_LOCK
+ * Introduce MALLOC_FAILURE_ACTION, MORECORE_CONTIGUOUS
+ Thanks to Tony E. Bennett <tbennett@nvidia.com> and others.
+ * Include errno.h to support default failure action.
+
+ V2.6.6 Sun Dec 5 07:42:19 1999 Doug Lea (dl at gee)
+ * return null for negative arguments
+ * Added Several WIN32 cleanups from Martin C. Fong <mcfong at yahoo.com>
+ * Add 'LACKS_SYS_PARAM_H' for those systems without 'sys/param.h'
+ (e.g. WIN32 platforms)
+ * Cleanup header file inclusion for WIN32 platforms
+ * Cleanup code to avoid Microsoft Visual C++ compiler complaints
+ * Add 'USE_DL_PREFIX' to quickly allow co-existence with existing
+ memory allocation routines
+ * Set 'malloc_getpagesize' for WIN32 platforms (needs more work)
+ * Use 'assert' rather than 'ASSERT' in WIN32 code to conform to
+ usage of 'assert' in non-WIN32 code
+ * Improve WIN32 'sbrk()' emulation's 'findRegion()' routine to
+ avoid infinite loop
+ * Always call 'fREe()' rather than 'free()'
+
+ V2.6.5 Wed Jun 17 15:57:31 1998 Doug Lea (dl at gee)
+ * Fixed ordering problem with boundary-stamping
+
+ V2.6.3 Sun May 19 08:17:58 1996 Doug Lea (dl at gee)
+ * Added pvalloc, as recommended by H.J. Liu
+ * Added 64bit pointer support mainly from Wolfram Gloger
+ * Added anonymously donated WIN32 sbrk emulation
+ * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen
+ * malloc_extend_top: fix mask error that caused wastage after
+ foreign sbrks
+ * Add linux mremap support code from HJ Liu
+
+ V2.6.2 Tue Dec 5 06:52:55 1995 Doug Lea (dl at gee)
+ * Integrated most documentation with the code.
+ * Add support for mmap, with help from
+ Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
+ * Use last_remainder in more cases.
+ * Pack bins using idea from colin@nyx10.cs.du.edu
+ * Use ordered bins instead of best-fit threshhold
+ * Eliminate block-local decls to simplify tracing and debugging.
+ * Support another case of realloc via move into top
+ * Fix error occuring when initial sbrk_base not word-aligned.
+ * Rely on page size for units instead of SBRK_UNIT to
+ avoid surprises about sbrk alignment conventions.
+ * Add mallinfo, mallopt. Thanks to Raymond Nijssen
+ (raymond@es.ele.tue.nl) for the suggestion.
+ * Add `pad' argument to malloc_trim and top_pad mallopt parameter.
+ * More precautions for cases where other routines call sbrk,
+ courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
+ * Added macros etc., allowing use in linux libc from
+ H.J. Lu (hjl@gnu.ai.mit.edu)
+ * Inverted this history list
+
+ V2.6.1 Sat Dec 2 14:10:57 1995 Doug Lea (dl at gee)
+ * Re-tuned and fixed to behave more nicely with V2.6.0 changes.
+ * Removed all preallocation code since under current scheme
+ the work required to undo bad preallocations exceeds
+ the work saved in good cases for most test programs.
+ * No longer use return list or unconsolidated bins since
+ no scheme using them consistently outperforms those that don't
+ given above changes.
+ * Use best fit for very large chunks to prevent some worst-cases.
+ * Added some support for debugging
+
+ V2.6.0 Sat Nov 4 07:05:23 1995 Doug Lea (dl at gee)
+ * Removed footers when chunks are in use. Thanks to
+ Paul Wilson (wilson@cs.texas.edu) for the suggestion.
+
+ V2.5.4 Wed Nov 1 07:54:51 1995 Doug Lea (dl at gee)
+ * Added malloc_trim, with help from Wolfram Gloger
+ (wmglo@Dent.MED.Uni-Muenchen.DE).
+
+ V2.5.3 Tue Apr 26 10:16:01 1994 Doug Lea (dl at g)
+
+ V2.5.2 Tue Apr 5 16:20:40 1994 Doug Lea (dl at g)
+ * realloc: try to expand in both directions
+ * malloc: swap order of clean-bin strategy;
+ * realloc: only conditionally expand backwards
+ * Try not to scavenge used bins
+ * Use bin counts as a guide to preallocation
+ * Occasionally bin return list chunks in first scan
+ * Add a few optimizations from colin@nyx10.cs.du.edu
+
+ V2.5.1 Sat Aug 14 15:40:43 1993 Doug Lea (dl at g)
+ * faster bin computation & slightly different binning
+ * merged all consolidations to one part of malloc proper
+ (eliminating old malloc_find_space & malloc_clean_bin)
+ * Scan 2 returns chunks (not just 1)
+ * Propagate failure in realloc if malloc returns 0
+ * Add stuff to allow compilation on non-ANSI compilers
+ from kpv@research.att.com
+
+ V2.5 Sat Aug 7 07:41:59 1993 Doug Lea (dl at g.oswego.edu)
+ * removed potential for odd address access in prev_chunk
+ * removed dependency on getpagesize.h
+ * misc cosmetics and a bit more internal documentation
+ * anticosmetics: mangled names in macros to evade debugger strangeness
+ * tested on sparc, hp-700, dec-mips, rs6000
+ with gcc & native cc (hp, dec only) allowing
+ Detlefs & Zorn comparison study (in SIGPLAN Notices.)
+
+ Trial version Fri Aug 28 13:14:29 1992 Doug Lea (dl at g.oswego.edu)
+ * Based loosely on libg++-1.2X malloc. (It retains some of the overall
+ structure of old version, but most details differ.)
+
+*/
+
+