--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/qtmobility/src/publishsubscribe/dlmalloc.c Fri Apr 16 15:51:22 2010 +0300
@@ -0,0 +1,5644 @@
+/*
+ This is a version (aka dlmalloc) of malloc/free/realloc written by
+ Doug Lea and released to the public domain. Use, modify, and
+ redistribute this code without permission or acknowledgement in any
+ way you wish. Send questions, comments, complaints, performance
+ data, etc to dl@cs.oswego.edu
+
+* VERSION 2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (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 (-O), and link it into another program. All
+ of the compile-time options default to reasonable values for use on
+ most unix platforms. Compile -DWIN32 for reasonable defaults on windows.
+ 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-2.7.1.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.
+
+* Why use this malloc?
+
+ 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.
+
+ The main properties of the algorithms are:
+ * For large (>= 512 bytes) requests, it is a pure best-fit allocator,
+ with ties normally decided via FIFO (i.e. least recently used).
+ * For small (<= 64 bytes by default) requests, it is a caching
+ allocator, that maintains pools of quickly recycled chunks.
+ * In between, and for combinations of large and small requests, it does
+ the best it can trying to meet both goals at once.
+ * For very large requests (>= 128KB by default), it relies on system
+ memory mapping facilities, if supported.
+
+ For a longer but slightly out of date high-level description, see
+ http://gee.cs.oswego.edu/dl/html/malloc.html
+
+ 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 in order to
+ customize settings or to avoid overheads associated with library
+ versions.
+
+* Contents, described in more detail in "description of public routines" below.
+
+ Standard (ANSI/SVID/...) functions:
+ malloc(size_t n);
+ calloc(size_t n_elements, size_t element_size);
+ free(Void_t* p);
+ realloc(Void_t* p, size_t n);
+ memalign(size_t alignment, size_t n);
+ valloc(size_t n);
+ mallinfo()
+ mallopt(int parameter_number, int parameter_value)
+
+ Additional functions:
+ independent_calloc(size_t n_elements, size_t size, Void_t* chunks[]);
+ independent_comalloc(size_t n_elements, size_t sizes[], Void_t* chunks[]);
+ pvalloc(size_t n);
+ cfree(Void_t* p);
+ malloc_trim(size_t pad);
+ malloc_usable_size(Void_t* p);
+ malloc_stats();
+
+* Vital statistics:
+
+ Supported pointer representation: 4 or 8 bytes
+ Supported size_t representation: 4 or 8 bytes
+ Note that size_t is allowed to be 4 bytes even if pointers are 8.
+ You can adjust this by defining INTERNAL_SIZE_T
+
+ Alignment: 2 * sizeof(size_t) (default)
+ (i.e., 8 byte alignment with 4byte size_t). This suffices for
+ nearly all current machines and C compilers. However, you can
+ define MALLOC_ALIGNMENT to be wider than this if necessary.
+
+ Minimum overhead per allocated chunk: 4 or 8 bytes
+ Each malloced chunk has a hidden word of overhead holding size
+ and status information.
+
+ Minimum allocated size: 4-byte ptrs: 16 bytes (including 4 overhead)
+ 8-byte ptrs: 24/32 bytes (including, 4/8 overhead)
+
+ When a chunk is freed, 12 (for 4byte ptrs) or 20 (for 8 byte
+ ptrs but 4 byte size) or 24 (for 8/8) additional bytes are
+ needed; 4 (8) for a trailing size field and 8 (16) bytes for
+ free list pointers. Thus, the minimum allocatable size is
+ 16/24/32 bytes.
+
+ 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 2 *
+ sizeof(size_t) bytes plus the remainder from a system page (the
+ minimal mmap unit); typically 4096 or 8192 bytes.
+
+ Maximum allocated size: 4-byte size_t: 2^32 minus about two pages
+ 8-byte size_t: 2^64 minus about two pages
+
+ It is assumed that (possibly signed) size_t values suffice to
+ represent chunk sizes. `Possibly signed' is due to the fact
+ that `size_t' may be defined on a system as either a signed or
+ an unsigned type. The ISO C standard says that it must be
+ unsigned, but a few systems are known not to adhere to this.
+ Additionally, even when size_t is unsigned, sbrk (which is by
+ default used to obtain memory from system) accepts signed
+ arguments, and may not be able to handle size_t-wide arguments
+ with negative sign bit. Generally, values that would
+ appear as negative after accounting for overhead and alignment
+ are supported only via mmap(), which does not have this
+ limitation.
+
+ Requests for sizes outside the allowed range will perform an optional
+ failure action and then return null. (Requests may also
+ also fail because a system is out of memory.)
+
+ Thread-safety: NOT thread-safe unless USE_MALLOC_LOCK defined
+
+ When USE_MALLOC_LOCK is defined, wrappers are created to
+ surround every public call 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,
+ you would be far better off obtaining ptmalloc, which is
+ derived from a version of this malloc, and is well-tuned for
+ concurrent programs. (See http://www.malloc.de) Note that
+ even when USE_MALLOC_LOCK is defined, you can can guarantee
+ full thread-safety only if no threads acquire memory through
+ direct calls to MORECORE or other system-level allocators.
+
+ Compliance: I believe it is compliant with the 1997 Single Unix Specification
+ (See http://www.opennc.org). Also SVID/XPG, ANSI C, and probably
+ others as well.
+
+* Synopsis of compile-time options:
+
+ People have reported using previous versions of this malloc on all
+ versions of Unix, sometimes by tweaking some of the defines
+ below. It has been tested most extensively on Solaris and
+ Linux. It is also reported to work on WIN32 platforms.
+ People also report using it in stand-alone embedded systems.
+
+ The implementation is in straight, hand-tuned ANSI C. It is not
+ at all modular. (Sorry!) It uses a lot of macros. To be at all
+ usable, this code should be compiled using an optimizing compiler
+ (for example gcc -O3) that can simplify expressions and control
+ paths. (FAQ: some macros import variables as arguments rather than
+ declare locals because people reported that some debuggers
+ otherwise get confused.)
+
+ OPTION DEFAULT VALUE
+
+ Compilation Environment options:
+
+ __STD_C derived from C compiler defines
+ WIN32 NOT defined
+ HAVE_MEMCPY defined
+ USE_MEMCPY 1 if HAVE_MEMCPY is defined
+ HAVE_MMAP defined as 1
+ MMAP_CLEARS 1
+ HAVE_MREMAP 0 unless linux defined
+ malloc_getpagesize derived from system #includes, or 4096 if not
+ HAVE_USR_INCLUDE_MALLOC_H NOT defined
+ LACKS_UNISTD_H NOT defined unless WIN32
+ LACKS_SYS_PARAM_H NOT defined unless WIN32
+ LACKS_SYS_MMAN_H NOT defined unless WIN32
+ LACKS_FCNTL_H NOT defined
+
+ Changing default word sizes:
+
+ INTERNAL_SIZE_T size_t
+ MALLOC_ALIGNMENT 2 * sizeof(INTERNAL_SIZE_T)
+ PTR_UINT unsigned long
+ CHUNK_SIZE_T unsigned long
+
+ Configuration and functionality options:
+
+ USE_DL_PREFIX NOT defined
+ USE_PUBLIC_MALLOC_WRAPPERS NOT defined
+ USE_MALLOC_LOCK NOT defined
+ DEBUG NOT defined
+ REALLOC_ZERO_BYTES_FREES NOT defined
+ MALLOC_FAILURE_ACTION errno = ENOMEM, if __STD_C defined, else no-op
+ TRIM_FASTBINS 0
+ FIRST_SORTED_BIN_SIZE 512
+
+ Options for customizing MORECORE:
+
+ MORECORE sbrk
+ MORECORE_CONTIGUOUS 1
+ MORECORE_CANNOT_TRIM NOT defined
+ MMAP_AS_MORECORE_SIZE (1024 * 1024)
+
+ Tuning options that are also dynamically changeable via mallopt:
+
+ DEFAULT_MXFAST 64
+ DEFAULT_TRIM_THRESHOLD 256 * 1024
+ DEFAULT_TOP_PAD 0
+ DEFAULT_MMAP_THRESHOLD 256 * 1024
+ DEFAULT_MMAP_MAX 65536
+
+ There are several other #defined constants and macros that you
+ probably don't want to touch unless you are extending or adapting malloc.
+*/
+
+/*
+ WIN32 sets up defaults for MS environment and compilers.
+ Otherwise defaults are for unix.
+*/
+
+/* #define WIN32 */
+
+#ifdef WIN32
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+/* Win32 doesn't supply or need the following headers */
+#define LACKS_UNISTD_H
+#define LACKS_SYS_PARAM_H
+#define LACKS_SYS_MMAN_H
+
+/* Use the supplied emulation of sbrk */
+#ifndef MORECORE
+#define MORECORE sbrk
+#endif
+#define MORECORE_CONTIGUOUS 1
+#define MORECORE_FAILURE ((void*)(-1))
+
+/* Use the supplied emulation of mmap and munmap */
+#ifndef HAVE_MMAP
+#define HAVE_MMAP 1
+#endif
+#define MUNMAP_FAILURE (-1)
+#define MMAP_CLEARS 1
+
+/* These values don't really matter in windows mmap emulation */
+#define MAP_PRIVATE 1
+#define MAP_ANONYMOUS 2
+#define PROT_READ 1
+#define PROT_WRITE 2
+
+/* Emulation functions defined at the end of this file */
+
+/* If USE_MALLOC_LOCK, use supplied critical-section-based lock functions */
+#ifdef USE_MALLOC_LOCK
+static int slwait(int *sl);
+static int slrelease(int *sl);
+#endif
+
+static long getpagesize(void);
+static long getregionsize(void);
+static void *sbrk(long size);
+static void *mmap(void *ptr, long size, long prot, long type, long handle, long arg);
+static long munmap(void *ptr, long size);
+
+static void vminfo (unsigned long*free, unsigned long*reserved, unsigned long*committed);
+static int cpuinfo (int whole, unsigned long*kernel, unsigned long*user);
+
+#endif
+
+/*
+ __STD_C should be nonzero if using ANSI-standard C compiler, a C++
+ compiler, or a C compiler sufficiently close to ANSI to get away
+ with it.
+*/
+
+#ifndef __STD_C
+#if defined(__STDC__) || defined(_cplusplus)
+#define __STD_C 1
+#else
+#define __STD_C 0
+#endif
+#endif /*__STD_C*/
+
+
+/*
+ Void_t* is the pointer type that malloc should say it returns
+*/
+
+#ifndef Void_t
+#if (__STD_C || defined(WIN32))
+#define Void_t void
+#else
+#define Void_t char
+#endif
+#endif /*Void_t*/
+
+#if __STD_C
+#include <stddef.h> /* for size_t */
+#else
+#include <sys/types.h>
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* define LACKS_UNISTD_H if your system does not have a <unistd.h>. */
+
+/* #define LACKS_UNISTD_H */
+
+#ifndef LACKS_UNISTD_H
+#include <unistd.h>
+#endif
+
+/* define LACKS_SYS_PARAM_H if your system does not have a <sys/param.h>. */
+
+/* #define LACKS_SYS_PARAM_H */
+
+
+#include <stdio.h> /* needed for malloc_stats */
+
+#ifndef LACKS_ERRNO_H
+#include <errno.h> /* needed for optional MALLOC_FAILURE_ACTION */
+#endif
+
+/*
+ Debugging:
+
+ Because freed chunks may be overwritten with bookkeeping fields, this
+ malloc will often die when freed memory is overwritten by user
+ programs. This can be very effective (albeit in an annoying way)
+ in helping track down dangling pointers.
+
+ If you compile with -DDEBUG, a number of assertion checks are
+ enabled that will catch more memory errors. You probably won't be
+ able to make much sense of the actual assertion errors, but they
+ should help you locate incorrectly overwritten memory. 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 summmaries. (By nature, mmapped regions
+ cannot be checked very much automatically.)
+
+ Setting DEBUG may also be helpful if you are trying to modify
+ this code. The assertions in the check routines spell out in more
+ detail the assumptions and invariants underlying the algorithms.
+
+ Setting DEBUG does NOT provide an automated mechanism for checking
+ that all accesses to malloced memory stay within their
+ bounds. However, there are several add-ons and adaptations of this
+ or other mallocs available that do this.
+*/
+
+#if DEBUG
+#include <assert.h>
+#else
+#define assert(x) ((void)0)
+#endif
+
+/*
+ The unsigned integer type used for comparing any two chunk sizes.
+ This should be at least as wide as size_t, but should not be signed.
+*/
+
+#ifndef CHUNK_SIZE_T
+#define CHUNK_SIZE_T unsigned long
+#endif
+
+/*
+ The unsigned integer type used to hold addresses when they are are
+ manipulated as integers. Except that it is not defined on all
+ systems, intptr_t would suffice.
+*/
+#ifndef PTR_UINT
+#define PTR_UINT unsigned long
+#endif
+
+
+/*
+ INTERNAL_SIZE_T is the word-size used for internal bookkeeping
+ of chunk sizes.
+
+ The default version is the same as size_t.
+
+ While not strictly necessary, it is best to define this as an
+ unsigned type, even if size_t is a signed type. This may avoid some
+ artificial size limitations on some systems.
+
+ On a 64-bit machine, you may be able to reduce malloc overhead by
+ defining INTERNAL_SIZE_T to be a 32 bit `unsigned int' at the
+ expense of not being able to handle more than 2^32 of malloced
+ space. If this limitation is acceptable, you are encouraged to set
+ this unless you are on a platform requiring 16byte alignments. In
+ this case the alignment requirements turn out to negate any
+ potential advantages of decreasing size_t word size.
+
+ Implementors: Beware of the possible combinations of:
+ - INTERNAL_SIZE_T might be signed or unsigned, might be 32 or 64 bits,
+ and might be the same width as int or as long
+ - size_t might have different width and signedness as INTERNAL_SIZE_T
+ - int and long might be 32 or 64 bits, and might be the same width
+ To deal with this, most comparisons and difference computations
+ among INTERNAL_SIZE_Ts should cast them to CHUNK_SIZE_T, being
+ aware of the fact that casting an unsigned int to a wider long does
+ not sign-extend. (This also makes checking for negative numbers
+ awkward.) Some of these casts result in harmless compiler warnings
+ on some systems.
+*/
+
+#ifndef INTERNAL_SIZE_T
+#define INTERNAL_SIZE_T size_t
+#endif
+
+/* The corresponding word size */
+#define SIZE_SZ (sizeof(INTERNAL_SIZE_T))
+
+
+
+/*
+ MALLOC_ALIGNMENT is the minimum alignment for malloc'ed chunks.
+ It must be a power of two at least 2 * SIZE_SZ, 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.
+*/
+
+
+#ifndef MALLOC_ALIGNMENT
+#define MALLOC_ALIGNMENT (2 * SIZE_SZ)
+#endif
+
+/* The corresponding bit mask value */
+#define MALLOC_ALIGN_MASK (MALLOC_ALIGNMENT - 1)
+
+
+
+/*
+ REALLOC_ZERO_BYTES_FREES 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).
+*/
+
+/* #define REALLOC_ZERO_BYTES_FREES */
+
+/*
+ TRIM_FASTBINS controls whether free() of a very small chunk can
+ immediately lead to trimming. Setting to true (1) can reduce memory
+ footprint, but will almost always slow down programs that use a lot
+ of small chunks.
+
+ Define this only if you are willing to give up some speed to more
+ aggressively reduce system-level memory footprint when releasing
+ memory in programs that use many small chunks. You can get
+ essentially the same effect by setting MXFAST to 0, but this can
+ lead to even greater slowdowns in programs using many small chunks.
+ TRIM_FASTBINS is an in-between compile-time option, that disables
+ only those chunks bordering topmost memory from being placed in
+ fastbins.
+*/
+
+#ifndef TRIM_FASTBINS
+#define TRIM_FASTBINS 0
+#endif
+
+
+/*
+ USE_DL_PREFIX will prefix all public routines with the string 'dl'.
+ This is necessary when you only want to use this malloc in one part
+ of a program, using your regular system malloc elsewhere.
+*/
+
+/* #define USE_DL_PREFIX */
+
+
+/*
+ USE_MALLOC_LOCK causes wrapper functions to surround each
+ callable routine with pthread mutex lock/unlock.
+
+ USE_MALLOC_LOCK forces USE_PUBLIC_MALLOC_WRAPPERS to be defined
+*/
+
+
+/* #define USE_MALLOC_LOCK */
+
+
+/*
+ If USE_PUBLIC_MALLOC_WRAPPERS is defined, every public routine is
+ actually a wrapper function that first calls MALLOC_PREACTION, then
+ calls the internal routine, and follows it with
+ MALLOC_POSTACTION. This is needed for locking, but you can also use
+ this, without USE_MALLOC_LOCK, for purposes of interception,
+ instrumentation, etc. It is a sad fact that using wrappers often
+ noticeably degrades performance of malloc-intensive programs.
+*/
+
+#ifdef USE_MALLOC_LOCK
+#define USE_PUBLIC_MALLOC_WRAPPERS
+#else
+/* #define USE_PUBLIC_MALLOC_WRAPPERS */
+#endif
+
+
+/*
+ Two-phase name translation.
+ All of the actual routines are given mangled names.
+ When wrappers are used, they become the public callable versions.
+ When DL_PREFIX is used, the callable names are prefixed.
+*/
+
+#ifndef USE_PUBLIC_MALLOC_WRAPPERS
+#define cALLOc public_cALLOc
+#define fREe public_fREe
+#define cFREe public_cFREe
+#define mALLOc public_mALLOc
+#define mEMALIGn public_mEMALIGn
+#define rEALLOc public_rEALLOc
+#define vALLOc public_vALLOc
+#define pVALLOc public_pVALLOc
+#define mALLINFo public_mALLINFo
+#define mALLOPt public_mALLOPt
+#define mTRIm public_mTRIm
+#define mSTATs public_mSTATs
+#define mUSABLe public_mUSABLe
+#define iCALLOc public_iCALLOc
+#define iCOMALLOc public_iCOMALLOc
+#endif
+
+#ifdef USE_DL_PREFIX
+#define public_cALLOc dlcalloc
+#define public_fREe dlfree
+#define public_cFREe dlcfree
+#define public_mALLOc dlmalloc
+#define public_mEMALIGn dlmemalign
+#define public_rEALLOc dlrealloc
+#define public_vALLOc dlvalloc
+#define public_pVALLOc dlpvalloc
+#define public_mALLINFo dlmallinfo
+#define public_mALLOPt dlmallopt
+#define public_mTRIm dlmalloc_trim
+#define public_mSTATs dlmalloc_stats
+#define public_mUSABLe dlmalloc_usable_size
+#define public_iCALLOc dlindependent_calloc
+#define public_iCOMALLOc dlindependent_comalloc
+#else /* USE_DL_PREFIX */
+#define public_cALLOc calloc
+#define public_fREe free
+#define public_cFREe cfree
+#define public_mALLOc malloc
+#define public_mEMALIGn memalign
+#define public_rEALLOc realloc
+#define public_vALLOc valloc
+#define public_pVALLOc pvalloc
+#define public_mALLINFo mallinfo
+#define public_mALLOPt mallopt
+#define public_mTRIm malloc_trim
+#define public_mSTATs malloc_stats
+#define public_mUSABLe malloc_usable_size
+#define public_iCALLOc independent_calloc
+#define public_iCOMALLOc independent_comalloc
+#endif /* USE_DL_PREFIX */
+
+
+/*
+ HAVE_MEMCPY should be defined if you are not otherwise using
+ ANSI STD C, but still have memcpy and memset in your C library
+ and want to use them in calloc and realloc. Otherwise simple
+ macro versions are defined below.
+
+ USE_MEMCPY should be defined as 1 if you actually want to
+ have memset and memcpy called. People report that the macro
+ versions are faster than libc versions on some systems.
+
+ Even if USE_MEMCPY is set to 1, loops to copy/clear small chunks
+ (of <= 36 bytes) are manually unrolled in realloc and calloc.
+*/
+
+#define HAVE_MEMCPY
+
+#ifndef USE_MEMCPY
+#ifdef HAVE_MEMCPY
+#define USE_MEMCPY 1
+#else
+#define USE_MEMCPY 0
+#endif
+#endif
+
+
+#if (__STD_C || defined(HAVE_MEMCPY))
+
+#ifdef WIN32
+/* On Win32 memset and memcpy are already declared in windows.h */
+#else
+#if __STD_C
+void* memset(void*, int, size_t);
+void* memcpy(void*, const void*, size_t);
+#else
+Void_t* memset();
+Void_t* memcpy();
+#endif
+#endif
+#endif
+
+/*
+ MALLOC_FAILURE_ACTION is the action to take before "return 0" when
+ malloc fails to be able to return memory, either because memory is
+ exhausted or because of illegal arguments.
+
+ By default, sets errno if running on STD_C platform, else does nothing.
+*/
+
+#ifndef MALLOC_FAILURE_ACTION
+#if __STD_C
+#define MALLOC_FAILURE_ACTION \
+ errno = ENOMEM;
+
+#else
+#define MALLOC_FAILURE_ACTION
+#endif
+#endif
+
+/*
+ MORECORE-related declarations. By default, rely on sbrk
+*/
+
+
+#ifdef LACKS_UNISTD_H
+#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
+#if __STD_C
+extern Void_t* sbrk(ptrdiff_t);
+#else
+extern Void_t* sbrk();
+#endif
+#endif
+#endif
+
+/*
+ MORECORE is the name of the routine to call to obtain more memory
+ from the system. See below for general guidance on writing
+ alternative MORECORE functions, as well as a version for WIN32 and a
+ sample version for pre-OSX macos.
+*/
+
+#ifndef MORECORE
+#define MORECORE sbrk
+#endif
+
+/*
+ MORECORE_FAILURE is the value returned upon failure of MORECORE
+ as well as mmap. Since it cannot be an otherwise valid memory address,
+ and must reflect values of standard sys calls, you probably ought not
+ try to redefine it.
+*/
+
+#ifndef MORECORE_FAILURE
+#define MORECORE_FAILURE (-1)
+#endif
+
+/*
+ If MORECORE_CONTIGUOUS is true, take advantage of fact that
+ consecutive calls to MORECORE with positive arguments always return
+ contiguous increasing addresses. This is true of unix sbrk. Even
+ if not defined, when regions happen to be contiguous, malloc will
+ permit allocations spanning regions obtained from different
+ calls. But defining this when applicable enables some stronger
+ consistency checks and space efficiencies.
+*/
+
+#ifndef MORECORE_CONTIGUOUS
+#define MORECORE_CONTIGUOUS 1
+#endif
+
+/*
+ Define MORECORE_CANNOT_TRIM if your version of 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.
+*/
+
+/* #define MORECORE_CANNOT_TRIM */
+
+
+/*
+ Define HAVE_MMAP as true to optionally make malloc() use mmap() to
+ allocate very large blocks. These will be returned to the
+ operating system immediately after a free(). Also, if mmap
+ is available, it is used as a backup strategy in cases where
+ MORECORE fails to provide space from system.
+
+ This malloc is best tuned to work with mmap for large requests.
+ If you do not have mmap, operations involving very large chunks (1MB
+ or so) may be slower than you'd like.
+*/
+
+#ifndef HAVE_MMAP
+#define HAVE_MMAP 1
+#endif
+
+#if HAVE_MMAP
+/*
+ Standard unix mmap using /dev/zero clears memory so calloc doesn't
+ need to.
+*/
+
+#ifndef MMAP_CLEARS
+#define MMAP_CLEARS 1
+#endif
+
+#else /* no mmap */
+#ifndef MMAP_CLEARS
+#define MMAP_CLEARS 0
+#endif
+#endif
+
+
+/*
+ MMAP_AS_MORECORE_SIZE is the minimum mmap size argument to use if
+ sbrk fails, and mmap is used as a backup (which is done only if
+ HAVE_MMAP). The value must be a multiple of page size. This
+ backup strategy generally applies only when systems have "holes" in
+ address space, so sbrk cannot perform contiguous expansion, but
+ there is still space available on system. On systems for which
+ this is known to be useful (i.e. most linux kernels), this occurs
+ only when programs allocate huge amounts of memory. Between this,
+ and the fact that mmap regions tend to be limited, the size should
+ be large, to avoid too many mmap calls and thus avoid running out
+ of kernel resources.
+*/
+
+#ifndef MMAP_AS_MORECORE_SIZE
+#define MMAP_AS_MORECORE_SIZE (1024 * 1024)
+#endif
+
+/*
+ Define HAVE_MREMAP to make realloc() use mremap() to re-allocate
+ large blocks. This is currently only possible on Linux with
+ kernel versions newer than 1.3.77.
+*/
+
+#ifndef HAVE_MREMAP
+#ifdef linux
+#define HAVE_MREMAP 1
+#else
+#define HAVE_MREMAP 0
+#endif
+
+#endif /* HAVE_MMAP */
+
+
+/*
+ The system page size. To the extent possible, this malloc manages
+ memory from the system in page-size units. Note that this value is
+ cached during initialization into a field of malloc_state. So even
+ if malloc_getpagesize is a function, it is only called once.
+
+ The following mechanics for getpagesize were adapted from bsd/gnu
+ getpagesize.h. If none of the system-probes here apply, a value of
+ 4096 is used, which should be OK: If they don't apply, then using
+ the actual value probably doesn't impact performance.
+*/
+
+
+#ifndef malloc_getpagesize
+
+#ifndef LACKS_UNISTD_H
+# include <unistd.h>
+#endif
+
+# 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 (4096)
+# endif
+# endif
+# endif
+# endif
+# endif
+# endif
+# endif
+#endif
+
+/*
+ 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 SVID/XPG compliant system that has
+ a /usr/include/malloc.h defining struct mallinfo. (If you'd like to
+ install such a thing yourself, cut out the preliminary declarations
+ as described above and below and save them in a malloc.h file. But
+ there's no compelling reason to bother to do this.)
+
+ The main declaration needed is the mallinfo struct that is returned
+ (by-copy) by mallinfo(). The SVID/XPG 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 an SVID2/XPG2 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
+
+/* SVID2/XPG mallinfo structure */
+
+struct mallinfo {
+ int arena; /* non-mmapped space allocated from system */
+ int ordblks; /* number of free chunks */
+ int smblks; /* number of fastbin blocks */
+ int hblks; /* number of mmapped regions */
+ int hblkhd; /* space in mmapped regions */
+ int usmblks; /* maximum total allocated space */
+ int fsmblks; /* space available in freed fastbin blocks */
+ int uordblks; /* total allocated space */
+ int fordblks; /* total free space */
+ int keepcost; /* top-most, releasable (via malloc_trim) space */
+};
+
+/*
+ SVID/XPG defines four standard parameter numbers for mallopt,
+ normally defined in malloc.h. Only one of these (M_MXFAST) is used
+ in this malloc. The others (M_NLBLKS, M_GRAIN, M_KEEP) don't apply,
+ so setting them has no effect. But this malloc also supports other
+ options in mallopt described below.
+*/
+#endif
+
+
+/* ---------- description of public routines ------------ */
+
+/*
+ malloc(size_t n)
+ Returns a pointer to a newly allocated chunk of at least n bytes, or null
+ if no space is available. Additionally, on failure, errno is
+ set to ENOMEM on ANSI C systems.
+
+ If n is zero, malloc returns a minumum-sized chunk. (The minimum
+ size is 16 bytes on most 32bit systems, and 24 or 32 bytes on 64bit
+ systems.) On most systems, size_t is an unsigned type, so calls
+ with negative arguments 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.
+*/
+#if __STD_C
+Void_t* public_mALLOc(size_t);
+#else
+Void_t* public_mALLOc();
+#endif
+
+/*
+ free(Void_t* 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. It can have arbitrary (i.e., bad!)
+ effects if p has already been freed.
+
+ Unless disabled (using mallopt), freeing very large spaces will
+ when possible, automatically trigger operations that give
+ back unused memory to the system, thus reducing program footprint.
+*/
+#if __STD_C
+void public_fREe(Void_t*);
+#else
+void public_fREe();
+#endif
+
+/*
+ calloc(size_t n_elements, size_t element_size);
+ Returns a pointer to n_elements * element_size bytes, with all locations
+ set to zero.
+*/
+#if __STD_C
+Void_t* public_cALLOc(size_t, size_t);
+#else
+Void_t* public_cALLOc();
+#endif
+
+/*
+ realloc(Void_t* 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 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. Unless the #define
+ REALLOC_ZERO_BYTES_FREES is set, realloc with a size argument of
+ zero (re)allocates a minimum-sized chunk.
+
+ Large chunks that were internally obtained via mmap will always
+ be reallocated using malloc-copy-free sequences unless
+ the system supports MREMAP (currently only linux).
+
+ The old unix realloc convention of allowing the last-free'd chunk
+ to be used as an argument to realloc is not supported.
+*/
+#if __STD_C
+Void_t* public_rEALLOc(Void_t*, size_t);
+#else
+Void_t* public_rEALLOc();
+#endif
+
+/*
+ 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.
+*/
+#if __STD_C
+Void_t* public_mEMALIGn(size_t, size_t);
+#else
+Void_t* public_mEMALIGn();
+#endif
+
+/*
+ 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.
+*/
+#if __STD_C
+Void_t* public_vALLOc(size_t);
+#else
+Void_t* public_vALLOc();
+#endif
+
+
+
+/*
+ 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. Only one of these (M_MXFAST) is used
+ in this malloc. The others (M_NLBLKS, M_GRAIN, M_KEEP) don't apply,
+ so setting them has no effect. But this malloc also supports four
+ 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_MXFAST 1 64 0-80 (0 disables fastbins)
+ M_TRIM_THRESHOLD -1 256*1024 any (-1U disables trimming)
+ M_TOP_PAD -2 0 any
+ M_MMAP_THRESHOLD -3 256*1024 any (or 0 if no MMAP support)
+ M_MMAP_MAX -4 65536 any (0 disables use of mmap)
+*/
+#if __STD_C
+int public_mALLOPt(int, int);
+#else
+int public_mALLOPt();
+#endif
+
+
+/*
+ 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: the number of fastbin blocks (i.e., small chunks that
+ have been freed but not use resused or consolidated)
+ 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: total bytes held in fastbin blocks
+ 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.
+*/
+#if __STD_C
+struct mallinfo public_mALLINFo(void);
+#else
+struct mallinfo public_mALLINFo();
+#endif
+
+/*
+ independent_calloc(size_t n_elements, size_t element_size, Void_t* 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;
+ }
+*/
+#if __STD_C
+Void_t** public_iCALLOc(size_t, size_t, Void_t**);
+#else
+Void_t** public_iCALLOc();
+#endif
+
+/*
+ independent_comalloc(size_t n_elements, size_t sizes[], Void_t* 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.
+*/
+#if __STD_C
+Void_t** public_iCOMALLOc(size_t, size_t*, Void_t**);
+#else
+Void_t** public_iCOMALLOc();
+#endif
+
+
+/*
+ pvalloc(size_t n);
+ Equivalent to valloc(minimum-page-that-holds(n)), that is,
+ round up n to nearest pagesize.
+ */
+#if __STD_C
+Void_t* public_pVALLOc(size_t);
+#else
+Void_t* public_pVALLOc();
+#endif
+
+/*
+ cfree(Void_t* p);
+ Equivalent to free(p).
+
+ cfree is needed/defined on some systems that pair it with calloc,
+ for odd historical reasons (such as: cfree is used in example
+ code in the first edition of K&R).
+*/
+#if __STD_C
+void public_cFREe(Void_t*);
+#else
+void public_cFREe();
+#endif
+
+/*
+ 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. 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 (one page or less). 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.
+ On systems that do not support "negative sbrks", it will always
+ rreturn 0.
+*/
+#if __STD_C
+int public_mTRIm(size_t);
+#else
+int public_mTRIm();
+#endif
+
+/*
+ malloc_usable_size(Void_t* 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);
+
+*/
+#if __STD_C
+size_t public_mUSABLe(Void_t*);
+#else
+size_t public_mUSABLe();
+#endif
+
+/*
+ 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.
+
+*/
+#if __STD_C
+void public_mSTATs();
+#else
+void public_mSTATs();
+#endif
+
+/* mallopt tuning options */
+
+/*
+ M_MXFAST is the maximum request size used for "fastbins", special bins
+ that hold returned chunks without consolidating their spaces. This
+ enables future requests for chunks of the same size to be handled
+ very quickly, but can increase fragmentation, and thus increase the
+ overall memory footprint of a program.
+
+ This malloc manages fastbins very conservatively yet still
+ efficiently, so fragmentation is rarely a problem for values less
+ than or equal to the default. The maximum supported value of MXFAST
+ is 80. You wouldn't want it any higher than this anyway. Fastbins
+ are designed especially for use with many small structs, objects or
+ strings -- the default handles structs/objects/arrays with sizes up
+ to 16 4byte fields, or small strings representing words, tokens,
+ etc. Using fastbins for larger objects normally worsens
+ fragmentation without improving speed.
+
+ M_MXFAST is set in REQUEST size units. It is internally used in
+ chunksize units, which adds padding and alignment. You can reduce
+ M_MXFAST to 0 to disable all use of fastbins. This causes the malloc
+ algorithm to be a closer approximation of fifo-best-fit in all cases,
+ not just for larger requests, but will generally cause it to be
+ slower.
+*/
+
+
+/* M_MXFAST is a standard SVID/XPG tuning option, usually listed in malloc.h */
+#ifndef M_MXFAST
+#define M_MXFAST 1
+#endif
+
+#ifndef DEFAULT_MXFAST
+#define DEFAULT_MXFAST 64
+#endif
+
+
+/*
+ M_TRIM_THRESHOLD is 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.
+ 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.
+
+ The trim threshold and the mmap control parameters (see below)
+ can be traded off with one another. Trimming and mmapping are
+ two different ways of releasing unused memory back to the
+ system. Between these two, it is often possible to keep
+ system-level demands of a long-lived program down to a bare
+ minimum. For example, in one test suite of sessions measuring
+ the XF86 X server on Linux, using a trim threshold of 128K and a
+ mmap threshold of 192K led to near-minimal long term resource
+ consumption.
+
+ If you are using this malloc in a long-lived program, it should
+ pay to experiment with these values. 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's
+ worth it to tune for trimming rather tham memory mapping 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. And in well-behaved long-lived programs,
+ controlling release of large blocks via trimming versus mapping
+ is usually faster.
+
+ However, in most programs, these parameters serve mainly as
+ protection against the system-level effects of carrying around
+ massive amounts of unneeded memory. Since frequent calls to
+ sbrk, mmap, and munmap otherwise degrade performance, the default
+ parameters are set to relatively high values that serve only as
+ safeguards.
+
+ The trim value must be greater than page size to have any useful
+ effect. To disable trimming completely, you can set to
+ (unsigned long)(-1)
+
+ Trim settings interact with fastbin (MXFAST) settings: Unless
+ TRIM_FASTBINS is defined, automatic trimming never takes place upon
+ freeing a chunk with size less than or equal to MXFAST. Trimming is
+ instead delayed until subsequent freeing of larger chunks. However,
+ you can still force an attempted trim by calling malloc_trim.
+
+ Also, trimming is not generally possible in cases where
+ the main arena is obtained via mmap.
+
+ 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.
+*/
+
+#define M_TRIM_THRESHOLD -1
+
+#ifndef DEFAULT_TRIM_THRESHOLD
+#define DEFAULT_TRIM_THRESHOLD (256 * 1024)
+#endif
+
+/*
+ M_TOP_PAD is the amount of extra `padding' space to allocate or
+ retain whenever sbrk is called. It is used in two ways internally:
+
+ * When sbrk is called to extend the top of the arena to satisfy
+ a new malloc request, this much padding is added to the sbrk
+ request.
+
+ * When malloc_trim is called automatically from free(),
+ it is used as the `pad' argument.
+
+ In both cases, the actual amount of padding is rounded
+ so that the end of the arena is always a system page boundary.
+
+ The main reason for using padding is to avoid calling sbrk so
+ often. Having even a small pad greatly reduces the likelihood
+ that nearly every malloc request during program start-up (or
+ after trimming) will invoke sbrk, which needlessly wastes
+ time.
+
+ Automatic rounding-up to page-size units is normally sufficient
+ to avoid measurable overhead, so the default is 0. However, in
+ systems where sbrk is relatively slow, it can pay to increase
+ this value, at the expense of carrying around more memory than
+ the program needs.
+*/
+
+#define M_TOP_PAD -2
+
+#ifndef DEFAULT_TOP_PAD
+#define DEFAULT_TOP_PAD (0)
+#endif
+
+/*
+ M_MMAP_THRESHOLD is the request size threshold for using mmap()
+ to 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:
+
+ 1. 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.
+ 2. Mapped memory can never become `locked' between
+ other chunks, as can happen with normally allocated chunks, which
+ means that even trimming via malloc_trim would not release them.
+ 3. On some systems with "holes" in address spaces, mmap can obtain
+ memory that sbrk cannot.
+
+ However, it has the disadvantages that:
+
+ 1. The space cannot be reclaimed, consolidated, and then
+ used to service later requests, as happens with normal chunks.
+ 2. It can lead to more wastage because of mmap page alignment
+ requirements
+ 3. It causes malloc performance to be more dependent on host
+ system memory management support routines which may vary in
+ implementation quality and may impose arbitrary
+ limitations. Generally, servicing a request via normal
+ malloc steps is faster than going through a system's mmap.
+
+ The advantages of mmap nearly always outweigh disadvantages for
+ "large" chunks, but the value of "large" varies across systems. The
+ default is an empirically derived value that works well in most
+ systems.
+*/
+
+#define M_MMAP_THRESHOLD -3
+
+#ifndef DEFAULT_MMAP_THRESHOLD
+#define DEFAULT_MMAP_THRESHOLD (256 * 1024)
+#endif
+
+/*
+ M_MMAP_MAX is the maximum number of requests to simultaneously
+ service using mmap. This parameter exists because
+. Some systems have a limited number of internal tables for
+ use by mmap, and using more than a few of them may degrade
+ performance.
+
+ The default is set to a value that serves only as a safeguard.
+ Setting to 0 disables use of mmap for servicing large requests. If
+ HAVE_MMAP is not set, the default value is 0, and attempts to set it
+ to non-zero values in mallopt will fail.
+*/
+
+#define M_MMAP_MAX -4
+
+#ifndef DEFAULT_MMAP_MAX
+#if HAVE_MMAP
+#define DEFAULT_MMAP_MAX (65536)
+#else
+#define DEFAULT_MMAP_MAX (0)
+#endif
+#endif
+
+#ifdef __cplusplus
+}; /* end of extern "C" */
+#endif
+
+/*
+ ========================================================================
+ 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" */
+
+/* --------------------- public wrappers ---------------------- */
+
+#ifdef USE_PUBLIC_MALLOC_WRAPPERS
+
+/* Declare all routines as internal */
+#if __STD_C
+static Void_t* mALLOc(size_t);
+static void fREe(Void_t*);
+static Void_t* rEALLOc(Void_t*, size_t);
+static Void_t* mEMALIGn(size_t, size_t);
+static Void_t* vALLOc(size_t);
+static Void_t* pVALLOc(size_t);
+static Void_t* cALLOc(size_t, size_t);
+static Void_t** iCALLOc(size_t, size_t, Void_t**);
+static Void_t** iCOMALLOc(size_t, size_t*, Void_t**);
+static void cFREe(Void_t*);
+static int mTRIm(size_t);
+static size_t mUSABLe(Void_t*);
+static void mSTATs();
+static int mALLOPt(int, int);
+static struct mallinfo mALLINFo(void);
+#else
+static Void_t* mALLOc();
+static void fREe();
+static Void_t* rEALLOc();
+static Void_t* mEMALIGn();
+static Void_t* vALLOc();
+static Void_t* pVALLOc();
+static Void_t* cALLOc();
+static Void_t** iCALLOc();
+static Void_t** iCOMALLOc();
+static void cFREe();
+static int mTRIm();
+static size_t mUSABLe();
+static void mSTATs();
+static int mALLOPt();
+static struct mallinfo mALLINFo();
+#endif
+
+/*
+ MALLOC_PREACTION and MALLOC_POSTACTION should be
+ defined to return 0 on success, and nonzero on failure.
+ The return value of MALLOC_POSTACTION is currently ignored
+ in wrapper functions since there is no reasonable default
+ action to take on failure.
+*/
+
+
+#ifdef USE_MALLOC_LOCK
+
+#ifdef WIN32
+
+static int mALLOC_MUTEx;
+#define MALLOC_PREACTION slwait(&mALLOC_MUTEx)
+#define MALLOC_POSTACTION slrelease(&mALLOC_MUTEx)
+
+#else
+
+#include <pthread.h>
+
+static pthread_mutex_t mALLOC_MUTEx = PTHREAD_MUTEX_INITIALIZER;
+
+#define MALLOC_PREACTION pthread_mutex_lock(&mALLOC_MUTEx)
+#define MALLOC_POSTACTION pthread_mutex_unlock(&mALLOC_MUTEx)
+
+#endif /* USE_MALLOC_LOCK */
+
+#else
+
+/* Substitute anything you like for these */
+
+#define MALLOC_PREACTION (0)
+#define MALLOC_POSTACTION (0)
+
+#endif
+
+Void_t* public_mALLOc(size_t bytes) {
+ Void_t* m;
+ if (MALLOC_PREACTION != 0) {
+ return 0;
+ }
+ m = mALLOc(bytes);
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return m;
+}
+
+void public_fREe(Void_t* m) {
+ if (MALLOC_PREACTION != 0) {
+ return;
+ }
+ fREe(m);
+ if (MALLOC_POSTACTION != 0) {
+ }
+}
+
+Void_t* public_rEALLOc(Void_t* m, size_t bytes) {
+ if (MALLOC_PREACTION != 0) {
+ return 0;
+ }
+ m = rEALLOc(m, bytes);
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return m;
+}
+
+Void_t* public_mEMALIGn(size_t alignment, size_t bytes) {
+ Void_t* m;
+ if (MALLOC_PREACTION != 0) {
+ return 0;
+ }
+ m = mEMALIGn(alignment, bytes);
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return m;
+}
+
+Void_t* public_vALLOc(size_t bytes) {
+ Void_t* m;
+ if (MALLOC_PREACTION != 0) {
+ return 0;
+ }
+ m = vALLOc(bytes);
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return m;
+}
+
+Void_t* public_pVALLOc(size_t bytes) {
+ Void_t* m;
+ if (MALLOC_PREACTION != 0) {
+ return 0;
+ }
+ m = pVALLOc(bytes);
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return m;
+}
+
+Void_t* public_cALLOc(size_t n, size_t elem_size) {
+ Void_t* m;
+ if (MALLOC_PREACTION != 0) {
+ return 0;
+ }
+ m = cALLOc(n, elem_size);
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return m;
+}
+
+
+Void_t** public_iCALLOc(size_t n, size_t elem_size, Void_t** chunks) {
+ Void_t** m;
+ if (MALLOC_PREACTION != 0) {
+ return 0;
+ }
+ m = iCALLOc(n, elem_size, chunks);
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return m;
+}
+
+Void_t** public_iCOMALLOc(size_t n, size_t sizes[], Void_t** chunks) {
+ Void_t** m;
+ if (MALLOC_PREACTION != 0) {
+ return 0;
+ }
+ m = iCOMALLOc(n, sizes, chunks);
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return m;
+}
+
+void public_cFREe(Void_t* m) {
+ if (MALLOC_PREACTION != 0) {
+ return;
+ }
+ cFREe(m);
+ if (MALLOC_POSTACTION != 0) {
+ }
+}
+
+int public_mTRIm(size_t s) {
+ int result;
+ if (MALLOC_PREACTION != 0) {
+ return 0;
+ }
+ result = mTRIm(s);
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return result;
+}
+
+size_t public_mUSABLe(Void_t* m) {
+ size_t result;
+ if (MALLOC_PREACTION != 0) {
+ return 0;
+ }
+ result = mUSABLe(m);
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return result;
+}
+
+void public_mSTATs() {
+ if (MALLOC_PREACTION != 0) {
+ return;
+ }
+ mSTATs();
+ if (MALLOC_POSTACTION != 0) {
+ }
+}
+
+struct mallinfo public_mALLINFo() {
+ struct mallinfo m;
+ if (MALLOC_PREACTION != 0) {
+ struct mallinfo nm = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+ return nm;
+ }
+ m = mALLINFo();
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return m;
+}
+
+int public_mALLOPt(int p, int v) {
+ int result;
+ if (MALLOC_PREACTION != 0) {
+ return 0;
+ }
+ result = mALLOPt(p, v);
+ if (MALLOC_POSTACTION != 0) {
+ }
+ return result;
+}
+
+#endif
+
+
+
+/* ------------- Optional versions of memcopy ---------------- */
+
+
+#if USE_MEMCPY
+
+/*
+ Note: memcpy is ONLY invoked with non-overlapping regions,
+ so the (usually slower) memmove is not needed.
+*/
+
+#define MALLOC_COPY(dest, src, nbytes) memcpy(dest, src, nbytes)
+#define MALLOC_ZERO(dest, nbytes) memset(dest, 0, nbytes)
+
+#else /* !USE_MEMCPY */
+
+/* Use Duff's device for good zeroing/copying performance. */
+
+#define MALLOC_ZERO(charp, nbytes) \
+do { \
+ INTERNAL_SIZE_T* mzp = (INTERNAL_SIZE_T*)(charp); \
+ CHUNK_SIZE_T mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T); \
+ long mcn; \
+ if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \
+ switch (mctmp) { \
+ case 0: for(;;) { *mzp++ = 0; \
+ case 7: *mzp++ = 0; \
+ case 6: *mzp++ = 0; \
+ case 5: *mzp++ = 0; \
+ case 4: *mzp++ = 0; \
+ case 3: *mzp++ = 0; \
+ case 2: *mzp++ = 0; \
+ case 1: *mzp++ = 0; if(mcn <= 0) break; mcn--; } \
+ } \
+} while(0)
+
+#define MALLOC_COPY(dest,src,nbytes) \
+do { \
+ INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) src; \
+ INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) dest; \
+ CHUNK_SIZE_T mctmp = (nbytes)/sizeof(INTERNAL_SIZE_T); \
+ long mcn; \
+ if (mctmp < 8) mcn = 0; else { mcn = (mctmp-1)/8; mctmp %= 8; } \
+ switch (mctmp) { \
+ case 0: for(;;) { *mcdst++ = *mcsrc++; \
+ case 7: *mcdst++ = *mcsrc++; \
+ case 6: *mcdst++ = *mcsrc++; \
+ case 5: *mcdst++ = *mcsrc++; \
+ case 4: *mcdst++ = *mcsrc++; \
+ case 3: *mcdst++ = *mcsrc++; \
+ case 2: *mcdst++ = *mcsrc++; \
+ case 1: *mcdst++ = *mcsrc++; if(mcn <= 0) break; mcn--; } \
+ } \
+} while(0)
+
+#endif
+
+/* ------------------ MMAP support ------------------ */
+
+
+#if HAVE_MMAP
+
+#ifndef LACKS_FCNTL_H
+#include <fcntl.h>
+#endif
+
+#ifndef LACKS_SYS_MMAN_H
+#include <sys/mman.h>
+#endif
+
+#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
+#define MAP_ANONYMOUS MAP_ANON
+#endif
+
+/*
+ Nearly all versions of mmap support MAP_ANONYMOUS,
+ so the following is unlikely to be needed, but is
+ supplied just in case.
+*/
+
+#ifndef MAP_ANONYMOUS
+
+static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */
+
+#define MMAP(addr, size, prot, flags) ((dev_zero_fd < 0) ? \
+ (dev_zero_fd = open("/dev/zero", O_RDWR), \
+ mmap((addr), (size), (prot), (flags), dev_zero_fd, 0)) : \
+ mmap((addr), (size), (prot), (flags), dev_zero_fd, 0))
+
+#else
+
+#define MMAP(addr, size, prot, flags) \
+ (mmap((addr), (size), (prot), (flags)|MAP_ANONYMOUS, -1, 0))
+
+#endif
+
+
+#endif /* HAVE_MMAP */
+
+
+/*
+ ----------------------- Chunk representations -----------------------
+*/
+
+
+/*
+ This struct declaration is misleading (but accurate and necessary).
+ It declares a "view" into memory allowing access to necessary
+ fields at known offsets from a given base. See explanation below.
+*/
+
+struct malloc_chunk {
+
+ INTERNAL_SIZE_T prev_size; /* Size of previous chunk (if free). */
+ INTERNAL_SIZE_T size; /* Size in bytes, including overhead. */
+
+ struct malloc_chunk* fd; /* double links -- used only if free. */
+ struct malloc_chunk* bk;
+};
+
+
+typedef struct malloc_chunk* mchunkptr;
+
+/*
+ malloc_chunk details:
+
+ (The following includes lightly edited explanations by Colin Plumb.)
+
+ Chunks of memory are maintained using a `boundary tag' method as
+ described in e.g., Knuth or Standish. (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 very fast. The
+ size fields also hold bits representing whether chunks are free or
+ in use.
+
+ An allocated chunk looks like this:
+
+
+ chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Size of previous chunk, if allocated | |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Size of chunk, in bytes |P|
+ mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | User data starts here... .
+ . .
+ . (malloc_usable_space() bytes) .
+ . |
+nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ | Size of chunk |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+
+ Where "chunk" is the front of the chunk for the purpose of most of
+ the malloc code, but "mem" is the pointer that is returned to the
+ user. "Nextchunk" is the beginning of the next contiguous chunk.
+
+ Chunks always begin on even word boundries, so the mem portion
+ (which is returned to the user) is also on an even word boundary, and
+ thus at least double-word aligned.
+
+ Free 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 |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+ The P (PREV_INUSE) 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
+ prev_inuse 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.
+
+ Note that the `foot' of the current chunk is actually represented
+ as the prev_size 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 two exceptions to all this are
+
+ 1. The special chunk `top' doesn't bother using the
+ trailing size field since there is no next contiguous chunk
+ that would have to index off it. After initialization, `top'
+ is forced to always exist. If it would become less than
+ MINSIZE bytes long, it is replenished.
+
+ 2. Chunks allocated via mmap, which have the second-lowest-order
+ bit (IS_MMAPPED) set in their size fields. Because they are
+ allocated one-by-one, each must contain its own trailing size field.
+
+*/
+
+/*
+ ---------- Size and alignment checks and conversions ----------
+*/
+
+/* conversion from malloc headers to user pointers, and back */
+
+#define chunk2mem(p) ((Void_t*)((char*)(p) + 2*SIZE_SZ))
+#define mem2chunk(mem) ((mchunkptr)((char*)(mem) - 2*SIZE_SZ))
+
+/* The smallest possible chunk */
+#define MIN_CHUNK_SIZE (sizeof(struct malloc_chunk))
+
+/* The smallest size we can malloc is an aligned minimal chunk */
+
+#define MINSIZE \
+ (CHUNK_SIZE_T)(((MIN_CHUNK_SIZE+MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK))
+
+/* Check if m has acceptable alignment */
+
+#define aligned_OK(m) (((PTR_UINT)((m)) & (MALLOC_ALIGN_MASK)) == 0)
+
+
+/*
+ Check if a request is so large that it would wrap around zero when
+ padded and aligned. To simplify some other code, the bound is made
+ low enough so that adding MINSIZE will also not wrap around sero.
+*/
+
+#define REQUEST_OUT_OF_RANGE(req) \
+ ((CHUNK_SIZE_T)(req) >= \
+ (CHUNK_SIZE_T)(INTERNAL_SIZE_T)(-2 * MINSIZE))
+
+/* pad request bytes into a usable size -- internal version */
+
+#define request2size(req) \
+ (((req) + SIZE_SZ + MALLOC_ALIGN_MASK < MINSIZE) ? \
+ MINSIZE : \
+ ((req) + SIZE_SZ + MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK)
+
+/* Same, except also perform argument check */
+
+#define checked_request2size(req, sz) \
+ if (REQUEST_OUT_OF_RANGE(req)) { \
+ MALLOC_FAILURE_ACTION; \
+ return 0; \
+ } \
+ (sz) = request2size(req);
+
+/*
+ --------------- Physical chunk operations ---------------
+*/
+
+
+/* size field is or'ed with PREV_INUSE when previous adjacent chunk in use */
+#define PREV_INUSE 0x1
+
+/* extract inuse bit of previous chunk */
+#define prev_inuse(p) ((p)->size & PREV_INUSE)
+
+
+/* size field is or'ed with IS_MMAPPED if the chunk was obtained with mmap() */
+#define IS_MMAPPED 0x2
+
+/* check for mmap()'ed chunk */
+#define chunk_is_mmapped(p) ((p)->size & IS_MMAPPED)
+
+/*
+ Bits to mask off when extracting size
+
+ Note: IS_MMAPPED is intentionally not masked off from size field in
+ macros for which mmapped chunks should never be seen. This should
+ cause helpful core dumps to occur if it is tried by accident by
+ people extending or adapting this malloc.
+*/
+#define SIZE_BITS (PREV_INUSE|IS_MMAPPED)
+
+/* Get size, ignoring use bits */
+#define chunksize(p) ((p)->size & ~(SIZE_BITS))
+
+
+/* Ptr to next physical malloc_chunk. */
+#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->size & ~PREV_INUSE) ))
+
+/* Ptr to previous physical malloc_chunk */
+#define prev_chunk(p) ((mchunkptr)( ((char*)(p)) - ((p)->prev_size) ))
+
+/* Treat space at ptr + offset as a chunk */
+#define chunk_at_offset(p, s) ((mchunkptr)(((char*)(p)) + (s)))
+
+/* extract p's inuse bit */
+#define inuse(p)\
+((((mchunkptr)(((char*)(p))+((p)->size & ~PREV_INUSE)))->size) & PREV_INUSE)
+
+/* set/clear chunk as being inuse without otherwise disturbing */
+#define set_inuse(p)\
+((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size |= PREV_INUSE
+
+#define clear_inuse(p)\
+((mchunkptr)(((char*)(p)) + ((p)->size & ~PREV_INUSE)))->size &= ~(PREV_INUSE)
+
+
+/* check/set/clear inuse bits in known places */
+#define inuse_bit_at_offset(p, s)\
+ (((mchunkptr)(((char*)(p)) + (s)))->size & PREV_INUSE)
+
+#define set_inuse_bit_at_offset(p, s)\
+ (((mchunkptr)(((char*)(p)) + (s)))->size |= PREV_INUSE)
+
+#define clear_inuse_bit_at_offset(p, s)\
+ (((mchunkptr)(((char*)(p)) + (s)))->size &= ~(PREV_INUSE))
+
+
+/* Set size at head, without disturbing its use bit */
+#define set_head_size(p, s) ((p)->size = (((p)->size & PREV_INUSE) | (s)))
+
+/* Set size/use field */
+#define set_head(p, s) ((p)->size = (s))
+
+/* Set size at footer (only when chunk is not in use) */
+#define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_size = (s))
+
+
+/*
+ -------------------- Internal data structures --------------------
+
+ All internal state is held in an instance of malloc_state defined
+ below. There are no other static variables, except in two optional
+ cases:
+ * If USE_MALLOC_LOCK is defined, the mALLOC_MUTEx declared above.
+ * If HAVE_MMAP is true, but mmap doesn't support
+ MAP_ANONYMOUS, a dummy file descriptor for mmap.
+
+ Beware of lots of tricks that minimize the total bookkeeping space
+ requirements. The result is a little over 1K bytes (for 4byte
+ pointers and size_t.)
+*/
+
+/*
+ Bins
+
+ An array of bin headers for free chunks. Each bin is doubly
+ linked. The bins are approximately proportionally (log) spaced.
+ There are a lot of these bins (128). This may look excessive, but
+ works very well in practice. Most bins hold sizes that are
+ unusual as malloc request sizes, but are more usual for fragments
+ and consolidated sets of chunks, which is what these bins hold, so
+ they can be found quickly. All procedures maintain the invariant
+ that no consolidated chunk physically borders another one, so each
+ chunk in a list is known to be preceeded and followed by either
+ inuse chunks or the ends of memory.
+
+ Chunks in bins are kept in size order, with ties going to the
+ approximately least recently used chunk. Ordering isn't needed
+ for the small bins, which all contain the same-sized chunks, but
+ facilitates best-fit allocation for larger chunks. These lists
+ are just sequential. Keeping them in order almost never requires
+ enough traversal to warrant using fancier ordered data
+ structures.
+
+ Chunks of the same size are linked with the most
+ recently freed at the front, and allocations are taken from the
+ back. This results in LRU (FIFO) allocation order, which tends
+ to give each chunk an equal opportunity to be consolidated with
+ adjacent freed chunks, resulting in larger free chunks and less
+ fragmentation.
+
+ To simplify use in double-linked lists, each bin header acts
+ as a malloc_chunk. This avoids special-casing for headers.
+ But to conserve space and improve locality, we allocate
+ only the fd/bk pointers of bins, and then use repositioning tricks
+ to treat these as the fields of a malloc_chunk*.
+*/
+
+typedef struct malloc_chunk* mbinptr;
+
+/* addressing -- note that bin_at(0) does not exist */
+#define bin_at(m, i) ((mbinptr)((char*)&((m)->bins[(i)<<1]) - (SIZE_SZ<<1)))
+
+/* analog of ++bin */
+#define next_bin(b) ((mbinptr)((char*)(b) + (sizeof(mchunkptr)<<1)))
+
+/* Reminders about list directionality within bins */
+#define first(b) ((b)->fd)
+#define last(b) ((b)->bk)
+
+/* Take a chunk off a bin list */
+#define unlink(P, BK, FD) { \
+ FD = P->fd; \
+ BK = P->bk; \
+ FD->bk = BK; \
+ BK->fd = FD; \
+}
+
+/*
+ Indexing
+
+ Bins for sizes < 512 bytes contain chunks of all the same size, spaced
+ 8 bytes apart. Larger bins are approximately logarithmically spaced:
+
+ 64 bins of size 8
+ 32 bins of size 64
+ 16 bins of size 512
+ 8 bins of size 4096
+ 4 bins of size 32768
+ 2 bins of size 262144
+ 1 bin of size what's left
+
+ The bins top out around 1MB because we expect to service large
+ requests via mmap.
+*/
+
+#define NBINS 96
+#define NSMALLBINS 32
+#define SMALLBIN_WIDTH 8
+#define MIN_LARGE_SIZE 256
+
+#define in_smallbin_range(sz) \
+ ((CHUNK_SIZE_T)(sz) < (CHUNK_SIZE_T)MIN_LARGE_SIZE)
+
+#define smallbin_index(sz) (((unsigned)(sz)) >> 3)
+
+/*
+ Compute index for size. We expect this to be inlined when
+ compiled with optimization, else not, which works out well.
+*/
+static int largebin_index(unsigned int sz) {
+ unsigned int x = sz >> SMALLBIN_WIDTH;
+ unsigned int m; /* bit position of highest set bit of m */
+
+ if (x >= 0x10000) return NBINS-1;
+
+ /* On intel, use BSRL instruction to find highest bit */
+#if defined(__GNUC__) && defined(i386)
+
+ __asm__("bsrl %1,%0\n\t"
+ : "=r" (m)
+ : "g" (x));
+
+#else
+ {
+ /*
+ Based on branch-free nlz algorithm in chapter 5 of Henry
+ S. Warren Jr's book "Hacker's Delight".
+ */
+
+ unsigned int n = ((x - 0x100) >> 16) & 8;
+ x <<= n;
+ m = ((x - 0x1000) >> 16) & 4;
+ n += m;
+ x <<= m;
+ m = ((x - 0x4000) >> 16) & 2;
+ n += m;
+ x = (x << m) >> 14;
+ m = 13 - n + (x & ~(x>>1));
+ }
+#endif
+
+ /* Use next 2 bits to create finer-granularity bins */
+ return NSMALLBINS + (m << 2) + ((sz >> (m + 6)) & 3);
+}
+
+#define bin_index(sz) \
+ ((in_smallbin_range(sz)) ? smallbin_index(sz) : largebin_index(sz))
+
+/*
+ FIRST_SORTED_BIN_SIZE is the chunk size corresponding to the
+ first bin that is maintained in sorted order. This must
+ be the smallest size corresponding to a given bin.
+
+ Normally, this should be MIN_LARGE_SIZE. But you can weaken
+ best fit guarantees to sometimes speed up malloc by increasing value.
+ Doing this means that malloc may choose a chunk that is
+ non-best-fitting by up to the width of the bin.
+
+ Some useful cutoff values:
+ 512 - all bins sorted
+ 2560 - leaves bins <= 64 bytes wide unsorted
+ 12288 - leaves bins <= 512 bytes wide unsorted
+ 65536 - leaves bins <= 4096 bytes wide unsorted
+ 262144 - leaves bins <= 32768 bytes wide unsorted
+ -1 - no bins sorted (not recommended!)
+*/
+
+#define FIRST_SORTED_BIN_SIZE MIN_LARGE_SIZE
+/* #define FIRST_SORTED_BIN_SIZE 65536 */
+
+/*
+ Unsorted chunks
+
+ All remainders from chunk splits, as well as all returned chunks,
+ are first placed in the "unsorted" bin. They are then placed
+ in regular bins after malloc gives them ONE chance to be used before
+ binning. So, basically, the unsorted_chunks list acts as a queue,
+ with chunks being placed on it in free (and malloc_consolidate),
+ and taken off (to be either used or placed in bins) in malloc.
+*/
+
+/* The otherwise unindexable 1-bin is used to hold unsorted chunks. */
+#define unsorted_chunks(M) (bin_at(M, 1))
+
+/*
+ Top
+
+ The top-most available chunk (i.e., the one bordering the end of
+ available memory) is treated specially. It 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). Because top initially
+ points to its own bin with initial zero size, thus forcing
+ extension on the first malloc request, we avoid having any special
+ code in malloc to check whether it even exists yet. But we still
+ need to do so when getting memory from system, so we make
+ initial_top treat the bin as a legal but unusable chunk during the
+ interval between initialization and the first call to
+ sYSMALLOc. (This is somewhat delicate, since it relies on
+ the 2 preceding words to be zero during this interval as well.)
+*/
+
+/* Conveniently, the unsorted bin can be used as dummy top on first call */
+#define initial_top(M) (unsorted_chunks(M))
+
+/*
+ Binmap
+
+ To help compensate for the large number of bins, a one-level index
+ structure is used for bin-by-bin searching. `binmap' is a
+ bitvector recording whether bins are definitely empty so they can
+ be skipped over during during traversals. The bits are NOT always
+ cleared as soon as bins are empty, but instead only
+ when they are noticed to be empty during traversal in malloc.
+*/
+
+/* Conservatively use 32 bits per map word, even if on 64bit system */
+#define BINMAPSHIFT 5
+#define BITSPERMAP (1U << BINMAPSHIFT)
+#define BINMAPSIZE (NBINS / BITSPERMAP)
+
+#define idx2block(i) ((i) >> BINMAPSHIFT)
+#define idx2bit(i) ((1U << ((i) & ((1U << BINMAPSHIFT)-1))))
+
+#define mark_bin(m,i) ((m)->binmap[idx2block(i)] |= idx2bit(i))
+#define unmark_bin(m,i) ((m)->binmap[idx2block(i)] &= ~(idx2bit(i)))
+#define get_binmap(m,i) ((m)->binmap[idx2block(i)] & idx2bit(i))
+
+/*
+ Fastbins
+
+ An array of lists holding recently freed small chunks. Fastbins
+ are not doubly linked. It is faster to single-link them, and
+ since chunks are never removed from the middles of these lists,
+ double linking is not necessary. Also, unlike regular bins, they
+ are not even processed in FIFO order (they use faster LIFO) since
+ ordering doesn't much matter in the transient contexts in which
+ fastbins are normally used.
+
+ Chunks in fastbins keep their inuse bit set, so they cannot
+ be consolidated with other free chunks. malloc_consolidate
+ releases all chunks in fastbins and consolidates them with
+ other free chunks.
+*/
+
+typedef struct malloc_chunk* mfastbinptr;
+
+/* offset 2 to use otherwise unindexable first 2 bins */
+#define fastbin_index(sz) ((((unsigned int)(sz)) >> 3) - 2)
+
+/* The maximum fastbin request size we support */
+#define MAX_FAST_SIZE 80
+
+#define NFASTBINS (fastbin_index(request2size(MAX_FAST_SIZE))+1)
+
+/*
+ FASTBIN_CONSOLIDATION_THRESHOLD is the size of a chunk in free()
+ that triggers automatic consolidation of possibly-surrounding
+ fastbin chunks. This is a heuristic, so the exact value should not
+ matter too much. It is defined at half the default trim threshold as a
+ compromise heuristic to only attempt consolidation if it is likely
+ to lead to trimming. However, it is not dynamically tunable, since
+ consolidation reduces fragmentation surrounding loarge chunks even
+ if trimming is not used.
+*/
+
+#define FASTBIN_CONSOLIDATION_THRESHOLD \
+ ((unsigned long)(DEFAULT_TRIM_THRESHOLD) >> 1)
+
+/*
+ Since the lowest 2 bits in max_fast don't matter in size comparisons,
+ they are used as flags.
+*/
+
+/*
+ ANYCHUNKS_BIT held in max_fast indicates that there may be any
+ freed chunks at all. It is set true when entering a chunk into any
+ bin.
+*/
+
+#define ANYCHUNKS_BIT (1U)
+
+#define have_anychunks(M) (((M)->max_fast & ANYCHUNKS_BIT))
+#define set_anychunks(M) ((M)->max_fast |= ANYCHUNKS_BIT)
+#define clear_anychunks(M) ((M)->max_fast &= ~ANYCHUNKS_BIT)
+
+/*
+ FASTCHUNKS_BIT held in max_fast indicates that there are probably
+ some fastbin chunks. It is set true on entering a chunk into any
+ fastbin, and cleared only in malloc_consolidate.
+*/
+
+#define FASTCHUNKS_BIT (2U)
+
+#define have_fastchunks(M) (((M)->max_fast & FASTCHUNKS_BIT))
+#define set_fastchunks(M) ((M)->max_fast |= (FASTCHUNKS_BIT|ANYCHUNKS_BIT))
+#define clear_fastchunks(M) ((M)->max_fast &= ~(FASTCHUNKS_BIT))
+
+/*
+ Set value of max_fast.
+ Use impossibly small value if 0.
+*/
+
+#define set_max_fast(M, s) \
+ (M)->max_fast = (((s) == 0)? SMALLBIN_WIDTH: request2size(s)) | \
+ ((M)->max_fast & (FASTCHUNKS_BIT|ANYCHUNKS_BIT))
+
+#define get_max_fast(M) \
+ ((M)->max_fast & ~(FASTCHUNKS_BIT | ANYCHUNKS_BIT))
+
+
+/*
+ morecore_properties is a status word holding dynamically discovered
+ or controlled properties of the morecore function
+*/
+
+#define MORECORE_CONTIGUOUS_BIT (1U)
+
+#define contiguous(M) \
+ (((M)->morecore_properties & MORECORE_CONTIGUOUS_BIT))
+#define noncontiguous(M) \
+ (((M)->morecore_properties & MORECORE_CONTIGUOUS_BIT) == 0)
+#define set_contiguous(M) \
+ ((M)->morecore_properties |= MORECORE_CONTIGUOUS_BIT)
+#define set_noncontiguous(M) \
+ ((M)->morecore_properties &= ~MORECORE_CONTIGUOUS_BIT)
+
+
+/*
+ ----------- Internal state representation and initialization -----------
+*/
+
+struct malloc_state {
+
+ /* The maximum chunk size to be eligible for fastbin */
+ INTERNAL_SIZE_T max_fast; /* low 2 bits used as flags */
+
+ /* Fastbins */
+ mfastbinptr fastbins[NFASTBINS];
+
+ /* Base of the topmost chunk -- not otherwise kept in a bin */
+ mchunkptr top;
+
+ /* The remainder from the most recent split of a small request */
+ mchunkptr last_remainder;
+
+ /* Normal bins packed as described above */
+ mchunkptr bins[NBINS * 2];
+
+ /* Bitmap of bins. Trailing zero map handles cases of largest binned size */
+ unsigned int binmap[BINMAPSIZE+1];
+
+ /* Tunable parameters */
+ CHUNK_SIZE_T trim_threshold;
+ INTERNAL_SIZE_T top_pad;
+ INTERNAL_SIZE_T mmap_threshold;
+
+ /* Memory map support */
+ int n_mmaps;
+ int n_mmaps_max;
+ int max_n_mmaps;
+
+ /* Cache malloc_getpagesize */
+ unsigned int pagesize;
+
+ /* Track properties of MORECORE */
+ unsigned int morecore_properties;
+
+ /* Statistics */
+ INTERNAL_SIZE_T mmapped_mem;
+ INTERNAL_SIZE_T sbrked_mem;
+ INTERNAL_SIZE_T max_sbrked_mem;
+ INTERNAL_SIZE_T max_mmapped_mem;
+ INTERNAL_SIZE_T max_total_mem;
+};
+
+typedef struct malloc_state *mstate;
+
+/*
+ There is exactly one instance of this struct in this malloc.
+ If you are adapting this malloc in a way that does NOT use a static
+ malloc_state, you MUST explicitly zero-fill it before using. This
+ malloc relies on the property that malloc_state is initialized to
+ all zeroes (as is true of C statics).
+*/
+
+#ifndef get_malloc_state
+static struct malloc_state av_; /* never directly referenced */
+
+/*
+ All uses of av_ are via get_malloc_state().
+ At most one "call" to get_malloc_state is made per invocation of
+ the public versions of malloc and free, but other routines
+ that in turn invoke malloc and/or free may call more then once.
+ Also, it is called in check* routines if DEBUG is set.
+*/
+
+#define get_malloc_state() (&(av_))
+#endif
+
+/*
+ Initialize a malloc_state struct.
+
+ This is called only from within malloc_consolidate, which needs
+ be called in the same contexts anyway. It is never called directly
+ outside of malloc_consolidate because some optimizing compilers try
+ to inline it at all call points, which turns out not to be an
+ optimization at all. (Inlining it in malloc_consolidate is fine though.)
+*/
+
+#if __STD_C
+static void malloc_init_state(mstate av)
+#else
+static void malloc_init_state(av) mstate av;
+#endif
+{
+ int i;
+ mbinptr bin;
+
+ /* Establish circular links for normal bins */
+ for (i = 1; i < NBINS; ++i) {
+ bin = bin_at(av,i);
+ bin->fd = bin->bk = bin;
+ }
+
+ av->top_pad = DEFAULT_TOP_PAD;
+ av->n_mmaps_max = DEFAULT_MMAP_MAX;
+ av->mmap_threshold = DEFAULT_MMAP_THRESHOLD;
+ av->trim_threshold = DEFAULT_TRIM_THRESHOLD;
+
+#if MORECORE_CONTIGUOUS
+ set_contiguous(av);
+#else
+ set_noncontiguous(av);
+#endif
+
+
+ set_max_fast(av, DEFAULT_MXFAST);
+
+ av->top = initial_top(av);
+ av->pagesize = malloc_getpagesize;
+}
+
+/*
+ Other internal utilities operating on mstates
+*/
+
+#if __STD_C
+static Void_t* sYSMALLOc(INTERNAL_SIZE_T, mstate);
+static int sYSTRIm(size_t, mstate);
+static void malloc_consolidate(mstate);
+static Void_t** iALLOc(size_t, size_t*, int, Void_t**);
+#else
+static Void_t* sYSMALLOc();
+static int sYSTRIm();
+static void malloc_consolidate();
+static Void_t** iALLOc();
+#endif
+
+/*
+ Debugging support
+
+ These routines make a number of assertions about the states
+ of data structures that should be true at all times. If any
+ are not true, it's very likely that a user program has somehow
+ trashed memory. (It's also possible that there is a coding error
+ in malloc. In which case, please report it!)
+*/
+
+#if ! DEBUG
+
+#define check_chunk(P)
+#define check_free_chunk(P)
+#define check_inuse_chunk(P)
+#define check_remalloced_chunk(P,N)
+#define check_malloced_chunk(P,N)
+#define check_malloc_state()
+
+#else
+#define check_chunk(P) do_check_chunk(P)
+#define check_free_chunk(P) do_check_free_chunk(P)
+#define check_inuse_chunk(P) do_check_inuse_chunk(P)
+#define check_remalloced_chunk(P,N) do_check_remalloced_chunk(P,N)
+#define check_malloced_chunk(P,N) do_check_malloced_chunk(P,N)
+#define check_malloc_state() do_check_malloc_state()
+
+/*
+ Properties of all chunks
+*/
+
+#if __STD_C
+static void do_check_chunk(mchunkptr p)
+#else
+static void do_check_chunk(p) mchunkptr p;
+#endif
+{
+ mstate av = get_malloc_state();
+ CHUNK_SIZE_T sz = chunksize(p);
+ /* min and max possible addresses assuming contiguous allocation */
+ char* max_address = (char*)(av->top) + chunksize(av->top);
+ char* min_address = max_address - av->sbrked_mem;
+
+ if (!chunk_is_mmapped(p)) {
+
+ /* Has legal address ... */
+ if (p != av->top) {
+ if (contiguous(av)) {
+ assert(((char*)p) >= min_address);
+ assert(((char*)p + sz) <= ((char*)(av->top)));
+ }
+ }
+ else {
+ /* top size is always at least MINSIZE */
+ assert((CHUNK_SIZE_T)(sz) >= MINSIZE);
+ /* top predecessor always marked inuse */
+ assert(prev_inuse(p));
+ }
+
+ }
+ else {
+#if HAVE_MMAP
+ /* address is outside main heap */
+ if (contiguous(av) && av->top != initial_top(av)) {
+ assert(((char*)p) < min_address || ((char*)p) > max_address);
+ }
+ /* chunk is page-aligned */
+ assert(((p->prev_size + sz) & (av->pagesize-1)) == 0);
+ /* mem is aligned */
+ assert(aligned_OK(chunk2mem(p)));
+#else
+ /* force an appropriate assert violation if debug set */
+ assert(!chunk_is_mmapped(p));
+#endif
+ }
+}
+
+/*
+ Properties of free chunks
+*/
+
+#if __STD_C
+static void do_check_free_chunk(mchunkptr p)
+#else
+static void do_check_free_chunk(p) mchunkptr p;
+#endif
+{
+ mstate av = get_malloc_state();
+
+ INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE;
+ mchunkptr next = chunk_at_offset(p, sz);
+
+ do_check_chunk(p);
+
+ /* Chunk must claim to be free ... */
+ assert(!inuse(p));
+ assert (!chunk_is_mmapped(p));
+
+ /* Unless a special marker, must have OK fields */
+ if ((CHUNK_SIZE_T)(sz) >= MINSIZE)
+ {
+ assert((sz & MALLOC_ALIGN_MASK) == 0);
+ assert(aligned_OK(chunk2mem(p)));
+ /* ... matching footer field */
+ assert(next->prev_size == sz);
+ /* ... and is fully consolidated */
+ assert(prev_inuse(p));
+ assert (next == av->top || inuse(next));
+
+ /* ... and has minimally sane links */
+ assert(p->fd->bk == p);
+ assert(p->bk->fd == p);
+ }
+ else /* markers are always of size SIZE_SZ */
+ assert(sz == SIZE_SZ);
+}
+
+/*
+ Properties of inuse chunks
+*/
+
+#if __STD_C
+static void do_check_inuse_chunk(mchunkptr p)
+#else
+static void do_check_inuse_chunk(p) mchunkptr p;
+#endif
+{
+ mstate av = get_malloc_state();
+ mchunkptr next;
+ do_check_chunk(p);
+
+ if (chunk_is_mmapped(p))
+ return; /* mmapped chunks have no next/prev */
+
+ /* Check whether it claims to be in use ... */
+ assert(inuse(p));
+
+ next = next_chunk(p);
+
+ /* ... and is surrounded by OK chunks.
+ Since more things can be checked with free chunks than inuse ones,
+ if an inuse chunk borders them and debug is on, it's worth doing them.
+ */
+ if (!prev_inuse(p)) {
+ /* Note that we cannot even look at prev unless it is not inuse */
+ mchunkptr prv = prev_chunk(p);
+ assert(next_chunk(prv) == p);
+ do_check_free_chunk(prv);
+ }
+
+ if (next == av->top) {
+ assert(prev_inuse(next));
+ assert(chunksize(next) >= MINSIZE);
+ }
+ else if (!inuse(next))
+ do_check_free_chunk(next);
+}
+
+/*
+ Properties of chunks recycled from fastbins
+*/
+
+#if __STD_C
+static void do_check_remalloced_chunk(mchunkptr p, INTERNAL_SIZE_T s)
+#else
+static void do_check_remalloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s;
+#endif
+{
+ INTERNAL_SIZE_T sz = p->size & ~PREV_INUSE;
+
+ do_check_inuse_chunk(p);
+
+ /* Legal size ... */
+ assert((sz & MALLOC_ALIGN_MASK) == 0);
+ assert((CHUNK_SIZE_T)(sz) >= MINSIZE);
+ /* ... and alignment */
+ assert(aligned_OK(chunk2mem(p)));
+ /* chunk is less than MINSIZE more than request */
+ assert((long)(sz) - (long)(s) >= 0);
+ assert((long)(sz) - (long)(s + MINSIZE) < 0);
+}
+
+/*
+ Properties of nonrecycled chunks at the point they are malloced
+*/
+
+#if __STD_C
+static void do_check_malloced_chunk(mchunkptr p, INTERNAL_SIZE_T s)
+#else
+static void do_check_malloced_chunk(p, s) mchunkptr p; INTERNAL_SIZE_T s;
+#endif
+{
+ /* same as recycled case ... */
+ do_check_remalloced_chunk(p, s);
+
+ /*
+ ... plus, must obey implementation invariant that prev_inuse is
+ always true of any allocated chunk; i.e., that 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. This does not necessarily hold however for chunks
+ recycled via fastbins.
+ */
+
+ assert(prev_inuse(p));
+}
+
+
+/*
+ Properties of malloc_state.
+
+ This may be useful for debugging malloc, as well as detecting user
+ programmer errors that somehow write into malloc_state.
+
+ If you are extending or experimenting with this malloc, you can
+ probably figure out how to hack this routine to print out or
+ display chunk addresses, sizes, bins, and other instrumentation.
+*/
+
+static void do_check_malloc_state()
+{
+ mstate av = get_malloc_state();
+ unsigned int i;
+ mchunkptr p;
+ mchunkptr q;
+ mbinptr b;
+ unsigned int binbit;
+ int empty;
+ unsigned int idx;
+ INTERNAL_SIZE_T size;
+ CHUNK_SIZE_T total = 0;
+ int max_fast_bin;
+
+ /* internal size_t must be no wider than pointer type */
+ assert(sizeof(INTERNAL_SIZE_T) <= sizeof(char*));
+
+ /* alignment is a power of 2 */
+ assert((MALLOC_ALIGNMENT & (MALLOC_ALIGNMENT-1)) == 0);
+
+ /* cannot run remaining checks until fully initialized */
+ if (av->top == 0 || av->top == initial_top(av))
+ return;
+
+ /* pagesize is a power of 2 */
+ assert((av->pagesize & (av->pagesize-1)) == 0);
+
+ /* properties of fastbins */
+
+ /* max_fast is in allowed range */
+ assert(get_max_fast(av) <= request2size(MAX_FAST_SIZE));
+
+ max_fast_bin = fastbin_index(av->max_fast);
+
+ for (i = 0; i < NFASTBINS; ++i) {
+ p = av->fastbins[i];
+
+ /* all bins past max_fast are empty */
+ if (i > max_fast_bin)
+ assert(p == 0);
+
+ while (p != 0) {
+ /* each chunk claims to be inuse */
+ do_check_inuse_chunk(p);
+ total += chunksize(p);
+ /* chunk belongs in this bin */
+ assert(fastbin_index(chunksize(p)) == i);
+ p = p->fd;
+ }
+ }
+
+ if (total != 0)
+ assert(have_fastchunks(av));
+ else if (!have_fastchunks(av))
+ assert(total == 0);
+
+ /* check normal bins */
+ for (i = 1; i < NBINS; ++i) {
+ b = bin_at(av,i);
+
+ /* binmap is accurate (except for bin 1 == unsorted_chunks) */
+ if (i >= 2) {
+ binbit = get_binmap(av,i);
+ empty = last(b) == b;
+ if (!binbit)
+ assert(empty);
+ else if (!empty)
+ assert(binbit);
+ }
+
+ for (p = last(b); p != b; p = p->bk) {
+ /* each chunk claims to be free */
+ do_check_free_chunk(p);
+ size = chunksize(p);
+ total += size;
+ if (i >= 2) {
+ /* chunk belongs in bin */
+ idx = bin_index(size);
+ assert(idx == i);
+ /* lists are sorted */
+ if ((CHUNK_SIZE_T) size >= (CHUNK_SIZE_T)(FIRST_SORTED_BIN_SIZE)) {
+ assert(p->bk == b ||
+ (CHUNK_SIZE_T)chunksize(p->bk) >=
+ (CHUNK_SIZE_T)chunksize(p));
+ }
+ }
+ /* chunk is followed by a legal chain of inuse chunks */
+ for (q = next_chunk(p);
+ (q != av->top && inuse(q) &&
+ (CHUNK_SIZE_T)(chunksize(q)) >= MINSIZE);
+ q = next_chunk(q))
+ do_check_inuse_chunk(q);
+ }
+ }
+
+ /* top chunk is OK */
+ check_chunk(av->top);
+
+ /* sanity checks for statistics */
+
+ assert(total <= (CHUNK_SIZE_T)(av->max_total_mem));
+ assert(av->n_mmaps >= 0);
+ assert(av->n_mmaps <= av->max_n_mmaps);
+
+ assert((CHUNK_SIZE_T)(av->sbrked_mem) <=
+ (CHUNK_SIZE_T)(av->max_sbrked_mem));
+
+ assert((CHUNK_SIZE_T)(av->mmapped_mem) <=
+ (CHUNK_SIZE_T)(av->max_mmapped_mem));
+
+ assert((CHUNK_SIZE_T)(av->max_total_mem) >=
+ (CHUNK_SIZE_T)(av->mmapped_mem) + (CHUNK_SIZE_T)(av->sbrked_mem));
+}
+#endif
+
+
+/* ----------- Routines dealing with system allocation -------------- */
+
+/*
+ sysmalloc handles malloc cases requiring more memory from the system.
+ On entry, it is assumed that av->top does not have enough
+ space to service request for nb bytes, thus requiring that av->top
+ be extended or replaced.
+*/
+
+#if __STD_C
+static Void_t* sYSMALLOc(INTERNAL_SIZE_T nb, mstate av)
+#else
+static Void_t* sYSMALLOc(nb, av) INTERNAL_SIZE_T nb; mstate av;
+#endif
+{
+ mchunkptr old_top; /* incoming value of av->top */
+ INTERNAL_SIZE_T old_size; /* its size */
+ char* old_end; /* its end address */
+
+ long size; /* arg to first MORECORE or mmap call */
+ char* brk; /* return value from MORECORE */
+
+ long correction; /* arg to 2nd MORECORE call */
+ char* snd_brk; /* 2nd return val */
+
+ INTERNAL_SIZE_T front_misalign; /* unusable bytes at front of new space */
+ INTERNAL_SIZE_T end_misalign; /* partial page left at end of new space */
+ char* aligned_brk; /* aligned offset into brk */
+
+ mchunkptr p; /* the allocated/returned chunk */
+ mchunkptr remainder; /* remainder from allocation */
+ CHUNK_SIZE_T remainder_size; /* its size */
+
+ CHUNK_SIZE_T sum; /* for updating stats */
+
+ size_t pagemask = av->pagesize - 1;
+
+ /*
+ If there is space available in fastbins, consolidate and retry
+ malloc from scratch rather than getting memory from system. This
+ can occur only if nb is in smallbin range so we didn't consolidate
+ upon entry to malloc. It is much easier to handle this case here
+ than in malloc proper.
+ */
+
+ if (have_fastchunks(av)) {
+ assert(in_smallbin_range(nb));
+ malloc_consolidate(av);
+ return mALLOc(nb - MALLOC_ALIGN_MASK);
+ }
+
+
+#if HAVE_MMAP
+
+ /*
+ If have mmap, and the request size meets the mmap threshold, and
+ the system supports mmap, and there are few enough currently
+ allocated mmapped regions, try to directly map this request
+ rather than expanding top.
+ */
+
+ if ((CHUNK_SIZE_T)(nb) >= (CHUNK_SIZE_T)(av->mmap_threshold) &&
+ (av->n_mmaps < av->n_mmaps_max)) {
+
+ char* mm; /* return value from mmap call*/
+
+ /*
+ Round up size to nearest page. For mmapped chunks, the overhead
+ is one SIZE_SZ unit larger than for normal chunks, because there
+ is no following chunk whose prev_size field could be used.
+ */
+ size = (nb + SIZE_SZ + MALLOC_ALIGN_MASK + pagemask) & ~pagemask;
+
+ /* Don't try if size wraps around 0 */
+ if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb)) {
+
+ mm = (char*)(MMAP(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE));
+
+ if (mm != (char*)(MORECORE_FAILURE)) {
+
+ /*
+ The offset to the start of the mmapped region is stored
+ in the prev_size field of the chunk. This allows us to adjust
+ returned start address to meet alignment requirements here
+ and in memalign(), and still be able to compute proper
+ address argument for later munmap in free() and realloc().
+ */
+
+ front_misalign = (INTERNAL_SIZE_T)chunk2mem(mm) & MALLOC_ALIGN_MASK;
+ if (front_misalign > 0) {
+ correction = MALLOC_ALIGNMENT - front_misalign;
+ p = (mchunkptr)(mm + correction);
+ p->prev_size = correction;
+ set_head(p, (size - correction) |IS_MMAPPED);
+ }
+ else {
+ p = (mchunkptr)mm;
+ p->prev_size = 0;
+ set_head(p, size|IS_MMAPPED);
+ }
+
+ /* update statistics */
+
+ if (++av->n_mmaps > av->max_n_mmaps)
+ av->max_n_mmaps = av->n_mmaps;
+
+ sum = av->mmapped_mem += size;
+ if (sum > (CHUNK_SIZE_T)(av->max_mmapped_mem))
+ av->max_mmapped_mem = sum;
+ sum += av->sbrked_mem;
+ if (sum > (CHUNK_SIZE_T)(av->max_total_mem))
+ av->max_total_mem = sum;
+
+ check_chunk(p);
+
+ return chunk2mem(p);
+ }
+ }
+ }
+#endif
+
+ /* Record incoming configuration of top */
+
+ old_top = av->top;
+ old_size = chunksize(old_top);
+ old_end = (char*)(chunk_at_offset(old_top, old_size));
+
+ brk = snd_brk = (char*)(MORECORE_FAILURE);
+
+ /*
+ If not the first time through, we require old_size to be
+ at least MINSIZE and to have prev_inuse set.
+ */
+
+ assert((old_top == initial_top(av) && old_size == 0) ||
+ ((CHUNK_SIZE_T) (old_size) >= MINSIZE &&
+ prev_inuse(old_top)));
+
+ /* Precondition: not enough current space to satisfy nb request */
+ assert((CHUNK_SIZE_T)(old_size) < (CHUNK_SIZE_T)(nb + MINSIZE));
+
+ /* Precondition: all fastbins are consolidated */
+ assert(!have_fastchunks(av));
+
+
+ /* Request enough space for nb + pad + overhead */
+
+ size = nb + av->top_pad + MINSIZE;
+
+ /*
+ If contiguous, we can subtract out existing space that we hope to
+ combine with new space. We add it back later only if
+ we don't actually get contiguous space.
+ */
+
+ if (contiguous(av))
+ size -= old_size;
+
+ /*
+ Round to a multiple of page size.
+ If MORECORE is not contiguous, this ensures that we only call it
+ with whole-page arguments. And if MORECORE is contiguous and
+ this is not first time through, this preserves page-alignment of
+ previous calls. Otherwise, we correct to page-align below.
+ */
+
+ size = (size + pagemask) & ~pagemask;
+
+ /*
+ Don't try to call MORECORE if argument is so big as to appear
+ negative. Note that since mmap takes size_t arg, it may succeed
+ below even if we cannot call MORECORE.
+ */
+
+ if (size > 0)
+ brk = (char*)(MORECORE(size));
+
+ /*
+ If have mmap, try using it as a backup when MORECORE fails or
+ cannot be used. This is worth doing on systems that have "holes" in
+ address space, so sbrk cannot extend to give contiguous space, but
+ space is available elsewhere. Note that we ignore mmap max count
+ and threshold limits, since the space will not be used as a
+ segregated mmap region.
+ */
+
+#if HAVE_MMAP
+ if (brk == (char*)(MORECORE_FAILURE)) {
+
+ /* Cannot merge with old top, so add its size back in */
+ if (contiguous(av))
+ size = (size + old_size + pagemask) & ~pagemask;
+
+ /* If we are relying on mmap as backup, then use larger units */
+ if ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(MMAP_AS_MORECORE_SIZE))
+ size = MMAP_AS_MORECORE_SIZE;
+
+ /* Don't try if size wraps around 0 */
+ if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb)) {
+
+ brk = (char*)(MMAP(0, size, PROT_READ|PROT_WRITE, MAP_PRIVATE));
+
+ if (brk != (char*)(MORECORE_FAILURE)) {
+
+ /* We do not need, and cannot use, another sbrk call to find end */
+ snd_brk = brk + size;
+
+ /*
+ Record that we no longer have a contiguous sbrk region.
+ After the first time mmap is used as backup, we do not
+ ever rely on contiguous space since this could incorrectly
+ bridge regions.
+ */
+ set_noncontiguous(av);
+ }
+ }
+ }
+#endif
+
+ if (brk != (char*)(MORECORE_FAILURE)) {
+ av->sbrked_mem += size;
+
+ /*
+ If MORECORE extends previous space, we can likewise extend top size.
+ */
+
+ if (brk == old_end && snd_brk == (char*)(MORECORE_FAILURE)) {
+ set_head(old_top, (size + old_size) | PREV_INUSE);
+ }
+
+ /*
+ Otherwise, make adjustments:
+
+ * If the first time through or noncontiguous, we need to call sbrk
+ just to find out where the end of memory lies.
+
+ * We need to ensure that all returned chunks from malloc will meet
+ MALLOC_ALIGNMENT
+
+ * If there was an intervening foreign sbrk, we need to adjust sbrk
+ request size to account for fact that we will not be able to
+ combine new space with existing space in old_top.
+
+ * Almost all systems internally allocate whole pages at a time, in
+ which case we might as well use the whole last page of request.
+ So we allocate enough more memory to hit a page boundary now,
+ which in turn causes future contiguous calls to page-align.
+ */
+
+ else {
+ front_misalign = 0;
+ end_misalign = 0;
+ correction = 0;
+ aligned_brk = brk;
+
+ /*
+ If MORECORE returns an address lower than we have seen before,
+ we know it isn't really contiguous. This and some subsequent
+ checks help cope with non-conforming MORECORE functions and
+ the presence of "foreign" calls to MORECORE from outside of
+ malloc or by other threads. We cannot guarantee to detect
+ these in all cases, but cope with the ones we do detect.
+ */
+ if (contiguous(av) && old_size != 0 && brk < old_end) {
+ set_noncontiguous(av);
+ }
+
+ /* handle contiguous cases */
+ if (contiguous(av)) {
+
+ /*
+ We can tolerate forward non-contiguities here (usually due
+ to foreign calls) but treat them as part of our space for
+ stats reporting.
+ */
+ if (old_size != 0)
+ av->sbrked_mem += brk - old_end;
+
+ /* Guarantee alignment of first new chunk made from this space */
+
+ front_misalign = (INTERNAL_SIZE_T)chunk2mem(brk) & MALLOC_ALIGN_MASK;
+ if (front_misalign > 0) {
+
+ /*
+ Skip over some bytes to arrive at an aligned position.
+ We don't need to specially mark these wasted front bytes.
+ They will never be accessed anyway because
+ prev_inuse of av->top (and any chunk created from its start)
+ is always true after initialization.
+ */
+
+ correction = MALLOC_ALIGNMENT - front_misalign;
+ aligned_brk += correction;
+ }
+
+ /*
+ If this isn't adjacent to existing space, then we will not
+ be able to merge with old_top space, so must add to 2nd request.
+ */
+
+ correction += old_size;
+
+ /* Extend the end address to hit a page boundary */
+ end_misalign = (INTERNAL_SIZE_T)(brk + size + correction);
+ correction += ((end_misalign + pagemask) & ~pagemask) - end_misalign;
+
+ assert(correction >= 0);
+ snd_brk = (char*)(MORECORE(correction));
+
+ if (snd_brk == (char*)(MORECORE_FAILURE)) {
+ /*
+ If can't allocate correction, try to at least find out current
+ brk. It might be enough to proceed without failing.
+ */
+ correction = 0;
+ snd_brk = (char*)(MORECORE(0));
+ }
+ else if (snd_brk < brk) {
+ /*
+ If the second call gives noncontiguous space even though
+ it says it won't, the only course of action is to ignore
+ results of second call, and conservatively estimate where
+ the first call left us. Also set noncontiguous, so this
+ won't happen again, leaving at most one hole.
+
+ Note that this check is intrinsically incomplete. Because
+ MORECORE is allowed to give more space than we ask for,
+ there is no reliable way to detect a noncontiguity
+ producing a forward gap for the second call.
+ */
+ snd_brk = brk + size;
+ correction = 0;
+ set_noncontiguous(av);
+ }
+
+ }
+
+ /* handle non-contiguous cases */
+ else {
+ /* MORECORE/mmap must correctly align */
+ assert(aligned_OK(chunk2mem(brk)));
+
+ /* Find out current end of memory */
+ if (snd_brk == (char*)(MORECORE_FAILURE)) {
+ snd_brk = (char*)(MORECORE(0));
+ av->sbrked_mem += snd_brk - brk - size;
+ }
+ }
+
+ /* Adjust top based on results of second sbrk */
+ if (snd_brk != (char*)(MORECORE_FAILURE)) {
+ av->top = (mchunkptr)aligned_brk;
+ set_head(av->top, (snd_brk - aligned_brk + correction) | PREV_INUSE);
+ av->sbrked_mem += correction;
+
+ /*
+ If not the first time through, we either have a
+ gap due to foreign sbrk or a non-contiguous region. Insert a
+ double fencepost at old_top to prevent consolidation with space
+ we don't own. These fenceposts are artificial chunks that are
+ marked as inuse and are in any case too small to use. We need
+ two to make sizes and alignments work out.
+ */
+
+ if (old_size != 0) {
+ /*
+ Shrink old_top to insert fenceposts, keeping size a
+ multiple of MALLOC_ALIGNMENT. We know there is at least
+ enough space in old_top to do this.
+ */
+ old_size = (old_size - 3*SIZE_SZ) & ~MALLOC_ALIGN_MASK;
+ set_head(old_top, old_size | PREV_INUSE);
+
+ /*
+ Note that the following assignments completely overwrite
+ old_top when old_size was previously MINSIZE. This is
+ intentional. We need the fencepost, even if old_top otherwise gets
+ lost.
+ */
+ chunk_at_offset(old_top, old_size )->size =
+ SIZE_SZ|PREV_INUSE;
+
+ chunk_at_offset(old_top, old_size + SIZE_SZ)->size =
+ SIZE_SZ|PREV_INUSE;
+
+ /*
+ If possible, release the rest, suppressing trimming.
+ */
+ if (old_size >= MINSIZE) {
+ INTERNAL_SIZE_T tt = av->trim_threshold;
+ av->trim_threshold = (INTERNAL_SIZE_T)(-1);
+ fREe(chunk2mem(old_top));
+ av->trim_threshold = tt;
+ }
+ }
+ }
+ }
+
+ /* Update statistics */
+ sum = av->sbrked_mem;
+ if (sum > (CHUNK_SIZE_T)(av->max_sbrked_mem))
+ av->max_sbrked_mem = sum;
+
+ sum += av->mmapped_mem;
+ if (sum > (CHUNK_SIZE_T)(av->max_total_mem))
+ av->max_total_mem = sum;
+
+ check_malloc_state();
+
+ /* finally, do the allocation */
+
+ p = av->top;
+ size = chunksize(p);
+
+ /* check that one of the above allocation paths succeeded */
+ if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb + MINSIZE)) {
+ remainder_size = size - nb;
+ remainder = chunk_at_offset(p, nb);
+ av->top = remainder;
+ set_head(p, nb | PREV_INUSE);
+ set_head(remainder, remainder_size | PREV_INUSE);
+ check_malloced_chunk(p, nb);
+ return chunk2mem(p);
+ }
+
+ }
+
+ /* catch all failure paths */
+ MALLOC_FAILURE_ACTION;
+ return 0;
+}
+
+
+
+
+/*
+ sYSTRIm is an inverse of sorts to sYSMALLOc. It gives memory back
+ to the system (via negative arguments to sbrk) if there is unused
+ memory at the `high' end of the malloc pool. It is called
+ automatically by free() when top space exceeds the trim
+ threshold. It is also called by the public malloc_trim routine. It
+ returns 1 if it actually released any memory, else 0.
+*/
+
+#if __STD_C
+static int sYSTRIm(size_t pad, mstate av)
+#else
+static int sYSTRIm(pad, av) size_t pad; mstate av;
+#endif
+{
+ long top_size; /* Amount of top-most memory */
+ long extra; /* Amount to release */
+ long released; /* Amount actually released */
+ char* current_brk; /* address returned by pre-check sbrk call */
+ char* new_brk; /* address returned by post-check sbrk call */
+ size_t pagesz;
+
+ pagesz = av->pagesize;
+ top_size = chunksize(av->top);
+
+ /* Release in pagesize units, keeping at least one page */
+ extra = ((top_size - pad - MINSIZE + (pagesz-1)) / pagesz - 1) * pagesz;
+
+ if (extra > 0) {
+
+ /*
+ Only proceed if end of memory is where we last set it.
+ This avoids problems if there were foreign sbrk calls.
+ */
+ current_brk = (char*)(MORECORE(0));
+ if (current_brk == (char*)(av->top) + top_size) {
+
+ /*
+ Attempt to release memory. We ignore MORECORE return value,
+ and instead call again to find out where new end of memory is.
+ This avoids problems if first call releases less than we asked,
+ of if failure somehow altered brk value. (We could still
+ encounter problems if it altered brk in some very bad way,
+ but the only thing we can do is adjust anyway, which will cause
+ some downstream failure.)
+ */
+
+ MORECORE(-extra);
+ new_brk = (char*)(MORECORE(0));
+
+ if (new_brk != (char*)MORECORE_FAILURE) {
+ released = (long)(current_brk - new_brk);
+
+ if (released != 0) {
+ /* Success. Adjust top. */
+ av->sbrked_mem -= released;
+ set_head(av->top, (top_size - released) | PREV_INUSE);
+ check_malloc_state();
+ return 1;
+ }
+ }
+ }
+ }
+ return 0;
+}
+
+/*
+ ------------------------------ malloc ------------------------------
+*/
+
+
+#if __STD_C
+Void_t* mALLOc(size_t bytes)
+#else
+ Void_t* mALLOc(bytes) size_t bytes;
+#endif
+{
+ mstate av = get_malloc_state();
+
+ INTERNAL_SIZE_T nb; /* normalized request size */
+ unsigned int idx; /* associated bin index */
+ mbinptr bin; /* associated bin */
+ mfastbinptr* fb; /* associated fastbin */
+
+ mchunkptr victim; /* inspected/selected chunk */
+ INTERNAL_SIZE_T size; /* its size */
+ int victim_index; /* its bin index */
+
+ mchunkptr remainder; /* remainder from a split */
+ CHUNK_SIZE_T remainder_size; /* its size */
+
+ unsigned int block; /* bit map traverser */
+ unsigned int bit; /* bit map traverser */
+ unsigned int map; /* current word of binmap */
+
+ mchunkptr fwd; /* misc temp for linking */
+ mchunkptr bck; /* misc temp for linking */
+
+ /*
+ Convert request size to internal form by adding SIZE_SZ bytes
+ overhead plus possibly more to obtain necessary alignment and/or
+ to obtain a size of at least MINSIZE, the smallest allocatable
+ size. Also, checked_request2size traps (returning 0) request sizes
+ that are so large that they wrap around zero when padded and
+ aligned.
+ */
+
+ checked_request2size(bytes, nb);
+
+ /*
+ Bypass search if no frees yet
+ */
+ if (!have_anychunks(av)) {
+ if (av->max_fast == 0) /* initialization check */
+ malloc_consolidate(av);
+ goto use_top;
+ }
+
+ /*
+ If the size qualifies as a fastbin, first check corresponding bin.
+ */
+
+ if ((CHUNK_SIZE_T)(nb) <= (CHUNK_SIZE_T)(av->max_fast)) {
+ fb = &(av->fastbins[(fastbin_index(nb))]);
+ if ( (victim = *fb) != 0) {
+ *fb = victim->fd;
+ check_remalloced_chunk(victim, nb);
+ return chunk2mem(victim);
+ }
+ }
+
+ /*
+ If a small request, check regular bin. Since these "smallbins"
+ hold one size each, no searching within bins is necessary.
+ (For a large request, we need to wait until unsorted chunks are
+ processed to find best fit. But for small ones, fits are exact
+ anyway, so we can check now, which is faster.)
+ */
+
+ if (in_smallbin_range(nb)) {
+ idx = smallbin_index(nb);
+ bin = bin_at(av,idx);
+
+ if ( (victim = last(bin)) != bin) {
+ bck = victim->bk;
+ set_inuse_bit_at_offset(victim, nb);
+ bin->bk = bck;
+ bck->fd = bin;
+
+ check_malloced_chunk(victim, nb);
+ return chunk2mem(victim);
+ }
+ }
+
+ /*
+ If this is a large request, consolidate fastbins before continuing.
+ While it might look excessive to kill all fastbins before
+ even seeing if there is space available, this avoids
+ fragmentation problems normally associated with fastbins.
+ Also, in practice, programs tend to have runs of either small or
+ large requests, but less often mixtures, so consolidation is not
+ invoked all that often in most programs. And the programs that
+ it is called frequently in otherwise tend to fragment.
+ */
+
+ else {
+ idx = largebin_index(nb);
+ if (have_fastchunks(av))
+ malloc_consolidate(av);
+ }
+
+ /*
+ Process recently freed or remaindered chunks, taking one only if
+ it is exact fit, or, if this a small request, the chunk is remainder from
+ the most recent non-exact fit. Place other traversed chunks in
+ bins. Note that this step is the only place in any routine where
+ chunks are placed in bins.
+ */
+
+ while ( (victim = unsorted_chunks(av)->bk) != unsorted_chunks(av)) {
+ bck = victim->bk;
+ size = chunksize(victim);
+
+ /*
+ If a small request, try to use last remainder if it is the
+ only chunk in unsorted bin. This helps promote locality for
+ runs of consecutive small requests. This is the only
+ exception to best-fit, and applies only when there is
+ no exact fit for a small chunk.
+ */
+
+ if (in_smallbin_range(nb) &&
+ bck == unsorted_chunks(av) &&
+ victim == av->last_remainder &&
+ (CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb + MINSIZE)) {
+
+ /* split and reattach remainder */
+ remainder_size = size - nb;
+ remainder = chunk_at_offset(victim, nb);
+ unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder;
+ av->last_remainder = remainder;
+ remainder->bk = remainder->fd = unsorted_chunks(av);
+
+ set_head(victim, nb | PREV_INUSE);
+ set_head(remainder, remainder_size | PREV_INUSE);
+ set_foot(remainder, remainder_size);
+
+ check_malloced_chunk(victim, nb);
+ return chunk2mem(victim);
+ }
+
+ /* remove from unsorted list */
+ unsorted_chunks(av)->bk = bck;
+ bck->fd = unsorted_chunks(av);
+
+ /* Take now instead of binning if exact fit */
+
+ if (size == nb) {
+ set_inuse_bit_at_offset(victim, size);
+ check_malloced_chunk(victim, nb);
+ return chunk2mem(victim);
+ }
+
+ /* place chunk in bin */
+
+ if (in_smallbin_range(size)) {
+ victim_index = smallbin_index(size);
+ bck = bin_at(av, victim_index);
+ fwd = bck->fd;
+ }
+ else {
+ victim_index = largebin_index(size);
+ bck = bin_at(av, victim_index);
+ fwd = bck->fd;
+
+ if (fwd != bck) {
+ /* if smaller than smallest, place first */
+ if ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(bck->bk->size)) {
+ fwd = bck;
+ bck = bck->bk;
+ }
+ else if ((CHUNK_SIZE_T)(size) >=
+ (CHUNK_SIZE_T)(FIRST_SORTED_BIN_SIZE)) {
+
+ /* maintain large bins in sorted order */
+ size |= PREV_INUSE; /* Or with inuse bit to speed comparisons */
+ while ((CHUNK_SIZE_T)(size) < (CHUNK_SIZE_T)(fwd->size))
+ fwd = fwd->fd;
+ bck = fwd->bk;
+ }
+ }
+ }
+
+ mark_bin(av, victim_index);
+ victim->bk = bck;
+ victim->fd = fwd;
+ fwd->bk = victim;
+ bck->fd = victim;
+ }
+
+ /*
+ If a large request, scan through the chunks of current bin to
+ find one that fits. (This will be the smallest that fits unless
+ FIRST_SORTED_BIN_SIZE has been changed from default.) This is
+ the only step where an unbounded number of chunks might be
+ scanned without doing anything useful with them. However the
+ lists tend to be short.
+ */
+
+ if (!in_smallbin_range(nb)) {
+ bin = bin_at(av, idx);
+
+ for (victim = last(bin); victim != bin; victim = victim->bk) {
+ size = chunksize(victim);
+
+ if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb)) {
+ remainder_size = size - nb;
+ unlink(victim, bck, fwd);
+
+ /* Exhaust */
+ if (remainder_size < MINSIZE) {
+ set_inuse_bit_at_offset(victim, size);
+ check_malloced_chunk(victim, nb);
+ return chunk2mem(victim);
+ }
+ /* Split */
+ else {
+ remainder = chunk_at_offset(victim, nb);
+ unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder;
+ remainder->bk = remainder->fd = unsorted_chunks(av);
+ set_head(victim, nb | PREV_INUSE);
+ set_head(remainder, remainder_size | PREV_INUSE);
+ set_foot(remainder, remainder_size);
+ check_malloced_chunk(victim, nb);
+ return chunk2mem(victim);
+ }
+ }
+ }
+ }
+
+ /*
+ Search for a chunk by scanning bins, starting with next largest
+ bin. This search is strictly by best-fit; i.e., the smallest
+ (with ties going to approximately the least recently used) chunk
+ that fits is selected.
+
+ The bitmap avoids needing to check that most blocks are nonempty.
+ */
+
+ ++idx;
+ bin = bin_at(av,idx);
+ block = idx2block(idx);
+ map = av->binmap[block];
+ bit = idx2bit(idx);
+
+ for (;;) {
+
+ /* Skip rest of block if there are no more set bits in this block. */
+ if (bit > map || bit == 0) {
+ do {
+ if (++block >= BINMAPSIZE) /* out of bins */
+ goto use_top;
+ } while ( (map = av->binmap[block]) == 0);
+
+ bin = bin_at(av, (block << BINMAPSHIFT));
+ bit = 1;
+ }
+
+ /* Advance to bin with set bit. There must be one. */
+ while ((bit & map) == 0) {
+ bin = next_bin(bin);
+ bit <<= 1;
+ assert(bit != 0);
+ }
+
+ /* Inspect the bin. It is likely to be non-empty */
+ victim = last(bin);
+
+ /* If a false alarm (empty bin), clear the bit. */
+ if (victim == bin) {
+ av->binmap[block] = map &= ~bit; /* Write through */
+ bin = next_bin(bin);
+ bit <<= 1;
+ }
+
+ else {
+ size = chunksize(victim);
+
+ /* We know the first chunk in this bin is big enough to use. */
+ assert((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb));
+
+ remainder_size = size - nb;
+
+ /* unlink */
+ bck = victim->bk;
+ bin->bk = bck;
+ bck->fd = bin;
+
+ /* Exhaust */
+ if (remainder_size < MINSIZE) {
+ set_inuse_bit_at_offset(victim, size);
+ check_malloced_chunk(victim, nb);
+ return chunk2mem(victim);
+ }
+
+ /* Split */
+ else {
+ remainder = chunk_at_offset(victim, nb);
+
+ unsorted_chunks(av)->bk = unsorted_chunks(av)->fd = remainder;
+ remainder->bk = remainder->fd = unsorted_chunks(av);
+ /* advertise as last remainder */
+ if (in_smallbin_range(nb))
+ av->last_remainder = remainder;
+
+ set_head(victim, nb | PREV_INUSE);
+ set_head(remainder, remainder_size | PREV_INUSE);
+ set_foot(remainder, remainder_size);
+ check_malloced_chunk(victim, nb);
+ return chunk2mem(victim);
+ }
+ }
+ }
+
+ use_top:
+ /*
+ If large enough, split off the chunk bordering the end of memory
+ (held in av->top). Note that this is in accord with the best-fit
+ search rule. In effect, av->top is treated as larger (and thus
+ less well fitting) than any other available chunk since it can
+ be extended to be as large as necessary (up to system
+ limitations).
+
+ We require that av->top always exists (i.e., has size >=
+ MINSIZE) after initialization, so if it would otherwise be
+ exhuasted by current request, it is replenished. (The main
+ reason for ensuring it exists is that we may need MINSIZE space
+ to put in fenceposts in sysmalloc.)
+ */
+
+ victim = av->top;
+ size = chunksize(victim);
+
+ if ((CHUNK_SIZE_T)(size) >= (CHUNK_SIZE_T)(nb + MINSIZE)) {
+ remainder_size = size - nb;
+ remainder = chunk_at_offset(victim, nb);
+ av->top = remainder;
+ set_head(victim, nb | PREV_INUSE);
+ set_head(remainder, remainder_size | PREV_INUSE);
+
+ check_malloced_chunk(victim, nb);
+ return chunk2mem(victim);
+ }
+
+ /*
+ If no space in top, relay to handle system-dependent cases
+ */
+ return sYSMALLOc(nb, av);
+}
+
+/*
+ ------------------------------ free ------------------------------
+*/
+
+#if __STD_C
+void fREe(Void_t* mem)
+#else
+void fREe(mem) Void_t* mem;
+#endif
+{
+ mstate av = get_malloc_state();
+
+ mchunkptr p; /* chunk corresponding to mem */
+ INTERNAL_SIZE_T size; /* its size */
+ mfastbinptr* fb; /* associated fastbin */
+ mchunkptr nextchunk; /* next contiguous chunk */
+ INTERNAL_SIZE_T nextsize; /* its size */
+ int nextinuse; /* true if nextchunk is used */
+ INTERNAL_SIZE_T prevsize; /* size of previous contiguous chunk */
+ mchunkptr bck; /* misc temp for linking */
+ mchunkptr fwd; /* misc temp for linking */
+
+ /* free(0) has no effect */
+ if (mem != 0) {
+ p = mem2chunk(mem);
+ size = chunksize(p);
+
+ check_inuse_chunk(p);
+
+ /*
+ If eligible, place chunk on a fastbin so it can be found
+ and used quickly in malloc.
+ */
+
+ if ((CHUNK_SIZE_T)(size) <= (CHUNK_SIZE_T)(av->max_fast)
+
+#if TRIM_FASTBINS
+ /*
+ If TRIM_FASTBINS set, don't place chunks
+ bordering top into fastbins
+ */
+ && (chunk_at_offset(p, size) != av->top)
+#endif
+ ) {
+
+ set_fastchunks(av);
+ fb = &(av->fastbins[fastbin_index(size)]);
+ p->fd = *fb;
+ *fb = p;
+ }
+
+ /*
+ Consolidate other non-mmapped chunks as they arrive.
+ */
+
+ else if (!chunk_is_mmapped(p)) {
+ set_anychunks(av);
+
+ nextchunk = chunk_at_offset(p, size);
+ nextsize = chunksize(nextchunk);
+
+ /* consolidate backward */
+ if (!prev_inuse(p)) {
+ prevsize = p->prev_size;
+ size += prevsize;
+ p = chunk_at_offset(p, -((long) prevsize));
+ unlink(p, bck, fwd);
+ }
+
+ if (nextchunk != av->top) {
+ /* get and clear inuse bit */
+ nextinuse = inuse_bit_at_offset(nextchunk, nextsize);
+ set_head(nextchunk, nextsize);
+
+ /* consolidate forward */
+ if (!nextinuse) {
+ unlink(nextchunk, bck, fwd);
+ size += nextsize;
+ }
+
+ /*
+ Place the chunk in unsorted chunk list. Chunks are
+ not placed into regular bins until after they have
+ been given one chance to be used in malloc.
+ */
+
+ bck = unsorted_chunks(av);
+ fwd = bck->fd;
+ p->bk = bck;
+ p->fd = fwd;
+ bck->fd = p;
+ fwd->bk = p;
+
+ set_head(p, size | PREV_INUSE);
+ set_foot(p, size);
+
+ check_free_chunk(p);
+ }
+
+ /*
+ If the chunk borders the current high end of memory,
+ consolidate into top
+ */
+
+ else {
+ size += nextsize;
+ set_head(p, size | PREV_INUSE);
+ av->top = p;
+ check_chunk(p);
+ }
+
+ /*
+ If freeing a large space, consolidate possibly-surrounding
+ chunks. Then, if the total unused topmost memory exceeds trim
+ threshold, ask malloc_trim to reduce top.
+
+ Unless max_fast is 0, we don't know if there are fastbins
+ bordering top, so we cannot tell for sure whether threshold
+ has been reached unless fastbins are consolidated. But we
+ don't want to consolidate on each free. As a compromise,
+ consolidation is performed if FASTBIN_CONSOLIDATION_THRESHOLD
+ is reached.
+ */
+
+ if ((CHUNK_SIZE_T)(size) >= FASTBIN_CONSOLIDATION_THRESHOLD) {
+ if (have_fastchunks(av))
+ malloc_consolidate(av);
+
+#ifndef MORECORE_CANNOT_TRIM
+ if ((CHUNK_SIZE_T)(chunksize(av->top)) >=
+ (CHUNK_SIZE_T)(av->trim_threshold))
+ sYSTRIm(av->top_pad, av);
+#endif
+ }
+
+ }
+ /*
+ If the chunk was allocated via mmap, release via munmap()
+ Note that if HAVE_MMAP is false but chunk_is_mmapped is
+ true, then user must have overwritten memory. There's nothing
+ we can do to catch this error unless DEBUG is set, in which case
+ check_inuse_chunk (above) will have triggered error.
+ */
+
+ else {
+#if HAVE_MMAP
+ int ret;
+ INTERNAL_SIZE_T offset = p->prev_size;
+ av->n_mmaps--;
+ av->mmapped_mem -= (size + offset);
+ ret = munmap((char*)p - offset, size + offset);
+ /* munmap returns non-zero on failure */
+ assert(ret == 0);
+#endif
+ }
+ }
+}
+
+/*
+ ------------------------- malloc_consolidate -------------------------
+
+ malloc_consolidate is a specialized version of free() that tears
+ down chunks held in fastbins. Free itself cannot be used for this
+ purpose since, among other things, it might place chunks back onto
+ fastbins. So, instead, we need to use a minor variant of the same
+ code.
+
+ Also, because this routine needs to be called the first time through
+ malloc anyway, it turns out to be the perfect place to trigger
+ initialization code.
+*/
+
+#if __STD_C
+static void malloc_consolidate(mstate av)
+#else
+static void malloc_consolidate(av) mstate av;
+#endif
+{
+ mfastbinptr* fb; /* current fastbin being consolidated */
+ mfastbinptr* maxfb; /* last fastbin (for loop control) */
+ mchunkptr p; /* current chunk being consolidated */
+ mchunkptr nextp; /* next chunk to consolidate */
+ mchunkptr unsorted_bin; /* bin header */
+ mchunkptr first_unsorted; /* chunk to link to */
+
+ /* These have same use as in free() */
+ mchunkptr nextchunk;
+ INTERNAL_SIZE_T size;
+ INTERNAL_SIZE_T nextsize;
+ INTERNAL_SIZE_T prevsize;
+ int nextinuse;
+ mchunkptr bck;
+ mchunkptr fwd;
+
+ /*
+ If max_fast is 0, we know that av hasn't
+ yet been initialized, in which case do so below
+ */
+
+ if (av->max_fast != 0) {
+ clear_fastchunks(av);
+
+ unsorted_bin = unsorted_chunks(av);
+
+ /*
+ Remove each chunk from fast bin and consolidate it, placing it
+ then in unsorted bin. Among other reasons for doing this,
+ placing in unsorted bin avoids needing to calculate actual bins
+ until malloc is sure that chunks aren't immediately going to be
+ reused anyway.
+ */
+
+ maxfb = &(av->fastbins[fastbin_index(av->max_fast)]);
+ fb = &(av->fastbins[0]);
+ do {
+ if ( (p = *fb) != 0) {
+ *fb = 0;
+
+ do {
+ check_inuse_chunk(p);
+ nextp = p->fd;
+
+ /* Slightly streamlined version of consolidation code in free() */
+ size = p->size & ~PREV_INUSE;
+ nextchunk = chunk_at_offset(p, size);
+ nextsize = chunksize(nextchunk);
+
+ if (!prev_inuse(p)) {
+ prevsize = p->prev_size;
+ size += prevsize;
+ p = chunk_at_offset(p, -((long) prevsize));
+ unlink(p, bck, fwd);
+ }
+
+ if (nextchunk != av->top) {
+ nextinuse = inuse_bit_at_offset(nextchunk, nextsize);
+ set_head(nextchunk, nextsize);
+
+ if (!nextinuse) {
+ size += nextsize;
+ unlink(nextchunk, bck, fwd);
+ }
+
+ first_unsorted = unsorted_bin->fd;
+ unsorted_bin->fd = p;
+ first_unsorted->bk = p;
+
+ set_head(p, size | PREV_INUSE);
+ p->bk = unsorted_bin;
+ p->fd = first_unsorted;
+ set_foot(p, size);
+ }
+
+ else {
+ size += nextsize;
+ set_head(p, size | PREV_INUSE);
+ av->top = p;
+ }
+
+ } while ( (p = nextp) != 0);
+
+ }
+ } while (fb++ != maxfb);
+ }
+ else {
+ malloc_init_state(av);
+ check_malloc_state();
+ }
+}
+
+/*
+ ------------------------------ realloc ------------------------------
+*/
+
+
+#if __STD_C
+Void_t* rEALLOc(Void_t* oldmem, size_t bytes)
+#else
+Void_t* rEALLOc(oldmem, bytes) Void_t* oldmem; size_t bytes;
+#endif
+{
+ mstate av = get_malloc_state();
+
+ INTERNAL_SIZE_T nb; /* padded request size */
+
+ mchunkptr oldp; /* chunk corresponding to oldmem */
+ INTERNAL_SIZE_T oldsize; /* its size */
+
+ mchunkptr newp; /* chunk to return */
+ INTERNAL_SIZE_T newsize; /* its size */
+ Void_t* newmem; /* corresponding user mem */
+
+ mchunkptr next; /* next contiguous chunk after oldp */
+
+ mchunkptr remainder; /* extra space at end of newp */
+ CHUNK_SIZE_T remainder_size; /* its size */
+
+ mchunkptr bck; /* misc temp for linking */
+ mchunkptr fwd; /* misc temp for linking */
+
+ CHUNK_SIZE_T copysize; /* bytes to copy */
+ unsigned int ncopies; /* INTERNAL_SIZE_T words to copy */
+ INTERNAL_SIZE_T* s; /* copy source */
+ INTERNAL_SIZE_T* d; /* copy destination */
+
+
+#ifdef REALLOC_ZERO_BYTES_FREES
+ if (bytes == 0) {
+ fREe(oldmem);
+ return 0;
+ }
+#endif
+
+ /* realloc of null is supposed to be same as malloc */
+ if (oldmem == 0) return mALLOc(bytes);
+
+ checked_request2size(bytes, nb);
+
+ oldp = mem2chunk(oldmem);
+ oldsize = chunksize(oldp);
+
+ check_inuse_chunk(oldp);
+
+ if (!chunk_is_mmapped(oldp)) {
+
+ if ((CHUNK_SIZE_T)(oldsize) >= (CHUNK_SIZE_T)(nb)) {
+ /* already big enough; split below */
+ newp = oldp;
+ newsize = oldsize;
+ }
+
+ else {
+ next = chunk_at_offset(oldp, oldsize);
+
+ /* Try to expand forward into top */
+ if (next == av->top &&
+ (CHUNK_SIZE_T)(newsize = oldsize + chunksize(next)) >=
+ (CHUNK_SIZE_T)(nb + MINSIZE)) {
+ set_head_size(oldp, nb);
+ av->top = chunk_at_offset(oldp, nb);
+ set_head(av->top, (newsize - nb) | PREV_INUSE);
+ return chunk2mem(oldp);
+ }
+
+ /* Try to expand forward into next chunk; split off remainder below */
+ else if (next != av->top &&
+ !inuse(next) &&
+ (CHUNK_SIZE_T)(newsize = oldsize + chunksize(next)) >=
+ (CHUNK_SIZE_T)(nb)) {
+ newp = oldp;
+ unlink(next, bck, fwd);
+ }
+
+ /* allocate, copy, free */
+ else {
+ newmem = mALLOc(nb - MALLOC_ALIGN_MASK);
+ if (newmem == 0)
+ return 0; /* propagate failure */
+
+ newp = mem2chunk(newmem);
+ newsize = chunksize(newp);
+
+ /*
+ Avoid copy if newp is next chunk after oldp.
+ */
+ if (newp == next) {
+ newsize += oldsize;
+ newp = oldp;
+ }
+ else {
+ /*
+ Unroll copy of <= 36 bytes (72 if 8byte sizes)
+ We know that contents have an odd number of
+ INTERNAL_SIZE_T-sized words; minimally 3.
+ */
+
+ copysize = oldsize - SIZE_SZ;
+ s = (INTERNAL_SIZE_T*)(oldmem);
+ d = (INTERNAL_SIZE_T*)(newmem);
+ ncopies = copysize / sizeof(INTERNAL_SIZE_T);
+ assert(ncopies >= 3);
+
+ if (ncopies > 9)
+ MALLOC_COPY(d, s, copysize);
+
+ else {
+ *(d+0) = *(s+0);
+ *(d+1) = *(s+1);
+ *(d+2) = *(s+2);
+ if (ncopies > 4) {
+ *(d+3) = *(s+3);
+ *(d+4) = *(s+4);
+ if (ncopies > 6) {
+ *(d+5) = *(s+5);
+ *(d+6) = *(s+6);
+ if (ncopies > 8) {
+ *(d+7) = *(s+7);
+ *(d+8) = *(s+8);
+ }
+ }
+ }
+ }
+
+ fREe(oldmem);
+ check_inuse_chunk(newp);
+ return chunk2mem(newp);
+ }
+ }
+ }
+
+ /* If possible, free extra space in old or extended chunk */
+
+ assert((CHUNK_SIZE_T)(newsize) >= (CHUNK_SIZE_T)(nb));
+
+ remainder_size = newsize - nb;
+
+ if (remainder_size < MINSIZE) { /* not enough extra to split off */
+ set_head_size(newp, newsize);
+ set_inuse_bit_at_offset(newp, newsize);
+ }
+ else { /* split remainder */
+ remainder = chunk_at_offset(newp, nb);
+ set_head_size(newp, nb);
+ set_head(remainder, remainder_size | PREV_INUSE);
+ /* Mark remainder as inuse so free() won't complain */
+ set_inuse_bit_at_offset(remainder, remainder_size);
+ fREe(chunk2mem(remainder));
+ }
+
+ check_inuse_chunk(newp);
+ return chunk2mem(newp);
+ }
+
+ /*
+ Handle mmap cases
+ */
+
+ else {
+#if HAVE_MMAP
+
+#if HAVE_MREMAP
+ INTERNAL_SIZE_T offset = oldp->prev_size;
+ size_t pagemask = av->pagesize - 1;
+ char *cp;
+ CHUNK_SIZE_T sum;
+
+ /* Note the extra SIZE_SZ overhead */
+ newsize = (nb + offset + SIZE_SZ + pagemask) & ~pagemask;
+
+ /* don't need to remap if still within same page */
+ if (oldsize == newsize - offset)
+ return oldmem;
+
+ cp = (char*)mremap((char*)oldp - offset, oldsize + offset, newsize, 1);
+
+ if (cp != (char*)MORECORE_FAILURE) {
+
+ newp = (mchunkptr)(cp + offset);
+ set_head(newp, (newsize - offset)|IS_MMAPPED);
+
+ assert(aligned_OK(chunk2mem(newp)));
+ assert((newp->prev_size == offset));
+
+ /* update statistics */
+ sum = av->mmapped_mem += newsize - oldsize;
+ if (sum > (CHUNK_SIZE_T)(av->max_mmapped_mem))
+ av->max_mmapped_mem = sum;
+ sum += av->sbrked_mem;
+ if (sum > (CHUNK_SIZE_T)(av->max_total_mem))
+ av->max_total_mem = sum;
+
+ return chunk2mem(newp);
+ }
+#endif
+
+ /* Note the extra SIZE_SZ overhead. */
+ if ((CHUNK_SIZE_T)(oldsize) >= (CHUNK_SIZE_T)(nb + SIZE_SZ))
+ newmem = oldmem; /* do nothing */
+ else {
+ /* Must alloc, copy, free. */
+ newmem = mALLOc(nb - MALLOC_ALIGN_MASK);
+ if (newmem != 0) {
+ MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ);
+ fREe(oldmem);
+ }
+ }
+ return newmem;
+
+#else
+ /* If !HAVE_MMAP, but chunk_is_mmapped, user must have overwritten mem */
+ check_malloc_state();
+ MALLOC_FAILURE_ACTION;
+ return 0;
+#endif
+ }
+}
+
+/*
+ ------------------------------ memalign ------------------------------
+*/
+
+#if __STD_C
+Void_t* mEMALIGn(size_t alignment, size_t bytes)
+#else
+Void_t* mEMALIGn(alignment, bytes) size_t alignment; size_t bytes;
+#endif
+{
+ INTERNAL_SIZE_T nb; /* padded request size */
+ char* m; /* memory returned by malloc call */
+ mchunkptr p; /* corresponding chunk */
+ char* brk; /* alignment point within p */
+ mchunkptr newp; /* chunk to return */
+ INTERNAL_SIZE_T newsize; /* its size */
+ INTERNAL_SIZE_T leadsize; /* leading space before alignment point */
+ mchunkptr remainder; /* spare room at end to split off */
+ CHUNK_SIZE_T remainder_size; /* its size */
+ INTERNAL_SIZE_T size;
+
+ /* If need less alignment than we give anyway, just relay to malloc */
+
+ if (alignment <= MALLOC_ALIGNMENT) return mALLOc(bytes);
+
+ /* Otherwise, ensure that it is at least a minimum chunk size */
+
+ if (alignment < MINSIZE) alignment = MINSIZE;
+
+ /* Make sure alignment is power of 2 (in case MINSIZE is not). */
+ if ((alignment & (alignment - 1)) != 0) {
+ size_t a = MALLOC_ALIGNMENT * 2;
+ while ((CHUNK_SIZE_T)a < (CHUNK_SIZE_T)alignment) a <<= 1;
+ alignment = a;
+ }
+
+ checked_request2size(bytes, nb);
+
+ /*
+ Strategy: find a spot within that chunk that meets the alignment
+ request, and then possibly free the leading and trailing space.
+ */
+
+
+ /* Call malloc with worst case padding to hit alignment. */
+
+ m = (char*)(mALLOc(nb + alignment + MINSIZE));
+
+ if (m == 0) return 0; /* propagate failure */
+
+ p = mem2chunk(m);
+
+ if ((((PTR_UINT)(m)) % alignment) != 0) { /* misaligned */
+
+ /*
+ Find an aligned spot inside chunk. Since we need to give back
+ leading space in a chunk of at least MINSIZE, if the first
+ calculation places us at a spot with less than MINSIZE leader,
+ we can move to the next aligned spot -- we've allocated enough
+ total room so that this is always possible.
+ */
+
+ brk = (char*)mem2chunk((PTR_UINT)(((PTR_UINT)(m + alignment - 1)) &
+ -((signed long) alignment)));
+ if ((CHUNK_SIZE_T)(brk - (char*)(p)) < MINSIZE)
+ brk += alignment;
+
+ newp = (mchunkptr)brk;
+ leadsize = brk - (char*)(p);
+ newsize = chunksize(p) - leadsize;
+
+ /* For mmapped chunks, just adjust offset */
+ if (chunk_is_mmapped(p)) {
+ newp->prev_size = p->prev_size + leadsize;
+ set_head(newp, newsize|IS_MMAPPED);
+ return chunk2mem(newp);
+ }
+
+ /* Otherwise, give back leader, use the rest */
+ set_head(newp, newsize | PREV_INUSE);
+ set_inuse_bit_at_offset(newp, newsize);
+ set_head_size(p, leadsize);
+ fREe(chunk2mem(p));
+ p = newp;
+
+ assert (newsize >= nb &&
+ (((PTR_UINT)(chunk2mem(p))) % alignment) == 0);
+ }
+
+ /* Also give back spare room at the end */
+ if (!chunk_is_mmapped(p)) {
+ size = chunksize(p);
+ if ((CHUNK_SIZE_T)(size) > (CHUNK_SIZE_T)(nb + MINSIZE)) {
+ remainder_size = size - nb;
+ remainder = chunk_at_offset(p, nb);
+ set_head(remainder, remainder_size | PREV_INUSE);
+ set_head_size(p, nb);
+ fREe(chunk2mem(remainder));
+ }
+ }
+
+ check_inuse_chunk(p);
+ return chunk2mem(p);
+}
+
+/*
+ ------------------------------ calloc ------------------------------
+*/
+
+#if __STD_C
+Void_t* cALLOc(size_t n_elements, size_t elem_size)
+#else
+Void_t* cALLOc(n_elements, elem_size) size_t n_elements; size_t elem_size;
+#endif
+{
+ mchunkptr p;
+ CHUNK_SIZE_T clearsize;
+ CHUNK_SIZE_T nclears;
+ INTERNAL_SIZE_T* d;
+
+ Void_t* mem = mALLOc(n_elements * elem_size);
+
+ if (mem != 0) {
+ p = mem2chunk(mem);
+
+ if (!chunk_is_mmapped(p))
+ {
+ /*
+ Unroll clear of <= 36 bytes (72 if 8byte sizes)
+ We know that contents have an odd number of
+ INTERNAL_SIZE_T-sized words; minimally 3.
+ */
+
+ d = (INTERNAL_SIZE_T*)mem;
+ clearsize = chunksize(p) - SIZE_SZ;
+ nclears = clearsize / sizeof(INTERNAL_SIZE_T);
+ assert(nclears >= 3);
+
+ if (nclears > 9)
+ MALLOC_ZERO(d, clearsize);
+
+ else {
+ *(d+0) = 0;
+ *(d+1) = 0;
+ *(d+2) = 0;
+ if (nclears > 4) {
+ *(d+3) = 0;
+ *(d+4) = 0;
+ if (nclears > 6) {
+ *(d+5) = 0;
+ *(d+6) = 0;
+ if (nclears > 8) {
+ *(d+7) = 0;
+ *(d+8) = 0;
+ }
+ }
+ }
+ }
+ }
+#if ! MMAP_CLEARS
+ else
+ {
+ d = (INTERNAL_SIZE_T*)mem;
+ /*
+ Note the additional SIZE_SZ
+ */
+ clearsize = chunksize(p) - 2*SIZE_SZ;
+ MALLOC_ZERO(d, clearsize);
+ }
+#endif
+ }
+ return mem;
+}
+
+/*
+ ------------------------------ cfree ------------------------------
+*/
+
+#if __STD_C
+void cFREe(Void_t *mem)
+#else
+void cFREe(mem) Void_t *mem;
+#endif
+{
+ fREe(mem);
+}
+
+/*
+ ------------------------- independent_calloc -------------------------
+*/
+
+#if __STD_C
+Void_t** iCALLOc(size_t n_elements, size_t elem_size, Void_t* chunks[])
+#else
+Void_t** iCALLOc(n_elements, elem_size, chunks) size_t n_elements; size_t elem_size; Void_t* chunks[];
+#endif
+{
+ size_t sz = elem_size; /* serves as 1-element array */
+ /* opts arg of 3 means all elements are same size, and should be cleared */
+ return iALLOc(n_elements, &sz, 3, chunks);
+}
+
+/*
+ ------------------------- independent_comalloc -------------------------
+*/
+
+#if __STD_C
+Void_t** iCOMALLOc(size_t n_elements, size_t sizes[], Void_t* chunks[])
+#else
+Void_t** iCOMALLOc(n_elements, sizes, chunks) size_t n_elements; size_t sizes[]; Void_t* chunks[];
+#endif
+{
+ return iALLOc(n_elements, sizes, 0, chunks);
+}
+
+
+/*
+ ------------------------------ ialloc ------------------------------
+ ialloc 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
+*/
+
+
+#if __STD_C
+static Void_t** iALLOc(size_t n_elements,
+ size_t* sizes,
+ int opts,
+ Void_t* chunks[])
+#else
+static Void_t** iALLOc(n_elements, sizes, opts, chunks) size_t n_elements; size_t* sizes; int opts; Void_t* chunks[];
+#endif
+{
+ mstate av = get_malloc_state();
+ INTERNAL_SIZE_T element_size; /* chunksize of each element, if all same */
+ INTERNAL_SIZE_T contents_size; /* total size of elements */
+ INTERNAL_SIZE_T array_size; /* request size of pointer array */
+ Void_t* mem; /* malloced aggregate space */
+ mchunkptr p; /* corresponding chunk */
+ INTERNAL_SIZE_T remainder_size; /* remaining bytes while splitting */
+ Void_t** marray; /* either "chunks" or malloced ptr array */
+ mchunkptr array_chunk; /* chunk for malloced ptr array */
+ int mmx; /* to disable mmap */
+ INTERNAL_SIZE_T size;
+ size_t i;
+
+ /* Ensure initialization */
+ if (av->max_fast == 0) malloc_consolidate(av);
+
+ /* 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_t**) mALLOc(0);
+ marray = 0;
+ array_size = request2size(n_elements * (sizeof(Void_t*)));
+ }
+
+ /* 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]);
+ }
+
+ /* subtract out alignment bytes from total to minimize overallocation */
+ size = contents_size + array_size - MALLOC_ALIGN_MASK;
+
+ /*
+ Allocate the aggregate chunk.
+ But first disable mmap so malloc won't use it, since
+ we would not be able to later free/realloc space internal
+ to a segregated mmap region.
+ */
+ mmx = av->n_mmaps_max; /* disable mmap */
+ av->n_mmaps_max = 0;
+ mem = mALLOc(size);
+ av->n_mmaps_max = mmx; /* reset mmap */
+ if (mem == 0)
+ return 0;
+
+ p = mem2chunk(mem);
+ assert(!chunk_is_mmapped(p));
+ remainder_size = chunksize(p);
+
+ if (opts & 0x2) { /* optionally clear the elements */
+ MALLOC_ZERO(mem, remainder_size - SIZE_SZ - array_size);
+ }
+
+ /* If not provided, allocate the pointer array as final part of chunk */
+ if (marray == 0) {
+ array_chunk = chunk_at_offset(p, contents_size);
+ marray = (Void_t**) (chunk2mem(array_chunk));
+ set_head(array_chunk, (remainder_size - contents_size) | PREV_INUSE);
+ 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_head(p, size | PREV_INUSE);
+ p = chunk_at_offset(p, size);
+ }
+ else { /* the final element absorbs any overallocation slop */
+ set_head(p, remainder_size | PREV_INUSE);
+ 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(mem2chunk(marray));
+ }
+
+ for (i = 0; i != n_elements; ++i)
+ check_inuse_chunk(mem2chunk(marray[i]));
+#endif
+
+ return marray;
+}
+
+
+/*
+ ------------------------------ valloc ------------------------------
+*/
+
+#if __STD_C
+Void_t* vALLOc(size_t bytes)
+#else
+Void_t* vALLOc(bytes) size_t bytes;
+#endif
+{
+ /* Ensure initialization */
+ mstate av = get_malloc_state();
+ if (av->max_fast == 0) malloc_consolidate(av);
+ return mEMALIGn(av->pagesize, bytes);
+}
+
+/*
+ ------------------------------ pvalloc ------------------------------
+*/
+
+
+#if __STD_C
+Void_t* pVALLOc(size_t bytes)
+#else
+Void_t* pVALLOc(bytes) size_t bytes;
+#endif
+{
+ mstate av = get_malloc_state();
+ size_t pagesz;
+
+ /* Ensure initialization */
+ if (av->max_fast == 0) malloc_consolidate(av);
+ pagesz = av->pagesize;
+ return mEMALIGn(pagesz, (bytes + pagesz - 1) & ~(pagesz - 1));
+}
+
+
+/*
+ ------------------------------ malloc_trim ------------------------------
+*/
+
+#if __STD_C
+int mTRIm(size_t pad)
+#else
+int mTRIm(pad) size_t pad;
+#endif
+{
+ mstate av = get_malloc_state();
+ /* Ensure initialization/consolidation */
+ malloc_consolidate(av);
+
+#ifndef MORECORE_CANNOT_TRIM
+ return sYSTRIm(pad, av);
+#else
+ return 0;
+#endif
+}
+
+
+/*
+ ------------------------- malloc_usable_size -------------------------
+*/
+
+#if __STD_C
+size_t mUSABLe(Void_t* mem)
+#else
+size_t mUSABLe(mem) Void_t* mem;
+#endif
+{
+ mchunkptr p;
+ if (mem != 0) {
+ p = mem2chunk(mem);
+ if (chunk_is_mmapped(p))
+ return chunksize(p) - 2*SIZE_SZ;
+ else if (inuse(p))
+ return chunksize(p) - SIZE_SZ;
+ }
+ return 0;
+}
+
+/*
+ ------------------------------ mallinfo ------------------------------
+*/
+
+struct mallinfo mALLINFo()
+{
+ mstate av = get_malloc_state();
+ struct mallinfo mi;
+ int i;
+ mbinptr b;
+ mchunkptr p;
+ INTERNAL_SIZE_T avail;
+ INTERNAL_SIZE_T fastavail;
+ int nblocks;
+ int nfastblocks;
+
+ /* Ensure initialization */
+ if (av->top == 0) malloc_consolidate(av);
+
+ check_malloc_state();
+
+ /* Account for top */
+ avail = chunksize(av->top);
+ nblocks = 1; /* top always exists */
+
+ /* traverse fastbins */
+ nfastblocks = 0;
+ fastavail = 0;
+
+ for (i = 0; i < (int)NFASTBINS; ++i) {
+ for (p = av->fastbins[i]; p != 0; p = p->fd) {
+ ++nfastblocks;
+ fastavail += chunksize(p);
+ }
+ }
+
+ avail += fastavail;
+
+ /* traverse regular bins */
+ for (i = 1; i < NBINS; ++i) {
+ b = bin_at(av, i);
+ for (p = last(b); p != b; p = p->bk) {
+ ++nblocks;
+ avail += chunksize(p);
+ }
+ }
+
+ mi.smblks = nfastblocks;
+ mi.ordblks = nblocks;
+ mi.fordblks = avail;
+ mi.uordblks = av->sbrked_mem - avail;
+ mi.arena = av->sbrked_mem;
+ mi.hblks = av->n_mmaps;
+ mi.hblkhd = av->mmapped_mem;
+ mi.fsmblks = fastavail;
+ mi.keepcost = chunksize(av->top);
+ mi.usmblks = av->max_total_mem;
+ return mi;
+}
+
+/*
+ ------------------------------ malloc_stats ------------------------------
+*/
+
+void mSTATs()
+{
+ struct mallinfo mi = mALLINFo();
+
+#ifdef WIN32
+ {
+ CHUNK_SIZE_T free, reserved, committed;
+ vminfo (&free, &reserved, &committed);
+ fprintf(stderr, "free bytes = %10lu\n",
+ free);
+ fprintf(stderr, "reserved bytes = %10lu\n",
+ reserved);
+ fprintf(stderr, "committed bytes = %10lu\n",
+ committed);
+ }
+#endif
+
+
+ fprintf(stderr, "max system bytes = %10lu\n",
+ (CHUNK_SIZE_T)(mi.usmblks));
+ fprintf(stderr, "system bytes = %10lu\n",
+ (CHUNK_SIZE_T)(mi.arena + mi.hblkhd));
+ fprintf(stderr, "in use bytes = %10lu\n",
+ (CHUNK_SIZE_T)(mi.uordblks + mi.hblkhd));
+
+#ifdef WIN32
+ {
+ CHUNK_SIZE_T kernel, user;
+ if (cpuinfo (TRUE, &kernel, &user)) {
+ fprintf(stderr, "kernel ms = %10lu\n",
+ kernel);
+ fprintf(stderr, "user ms = %10lu\n",
+ user);
+ }
+ }
+#endif
+}
+
+
+/*
+ ------------------------------ mallopt ------------------------------
+*/
+
+#if __STD_C
+int mALLOPt(int param_number, int value)
+#else
+int mALLOPt(param_number, value) int param_number; int value;
+#endif
+{
+ mstate av = get_malloc_state();
+ /* Ensure initialization/consolidation */
+ malloc_consolidate(av);
+
+ switch(param_number) {
+ case M_MXFAST:
+ if (value >= 0 && value <= MAX_FAST_SIZE) {
+ set_max_fast(av, value);
+ return 1;
+ }
+ else
+ return 0;
+
+ case M_TRIM_THRESHOLD:
+ av->trim_threshold = value;
+ return 1;
+
+ case M_TOP_PAD:
+ av->top_pad = value;
+ return 1;
+
+ case M_MMAP_THRESHOLD:
+ av->mmap_threshold = value;
+ return 1;
+
+ case M_MMAP_MAX:
+#if !HAVE_MMAP
+ if (value != 0)
+ return 0;
+#endif
+ av->n_mmaps_max = value;
+ return 1;
+
+ default:
+ return 0;
+ }
+}
+
+
+/*
+ -------------------- Alternative MORECORE functions --------------------
+*/
+
+
+/*
+ General Requirements for MORECORE.
+
+ The MORECORE function must have the following properties:
+
+ If MORECORE_CONTIGUOUS is false:
+
+ * MORECORE must allocate in multiples of pagesize. It will
+ only be called with arguments that are multiples of pagesize.
+
+ * MORECORE(0) must return an address that is at least
+ MALLOC_ALIGNMENT aligned. (Page-aligning always suffices.)
+
+ else (i.e. If MORECORE_CONTIGUOUS is true):
+
+ * Consecutive calls to MORECORE with positive arguments
+ return increasing addresses, indicating that space has been
+ contiguously extended.
+
+ * MORECORE need not allocate in multiples of pagesize.
+ Calls to MORECORE need not have args of multiples of pagesize.
+
+ * MORECORE need not page-align.
+
+ In either case:
+
+ * MORECORE may allocate more memory than requested. (Or even less,
+ but this will generally 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. This malloc does NOT call MORECORE(0)
+ until at least one call with positive arguments is made, so
+ the initial value returned is not important.
+
+ * 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 MORECORE_FAILURE 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,
+
+ There is some variation across systems about the type of the
+ argument to sbrk/MORECORE. If size_t is unsigned, then it cannot
+ actually be size_t, because sbrk supports negative args, so it is
+ normally the signed type of the same width as size_t (sometimes
+ declared as "intptr_t", and sometimes "ptrdiff_t"). It doesn't much
+ matter though. Internally, we use "long" as arguments, which should
+ work across all reasonable possibilities.
+
+ Additionally, if MORECORE ever returns failure for a positive
+ 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 map noncontiguous space.
+
+ If you'd like mmap to ALWAYS be used, you can define MORECORE to be
+ a function that always returns MORECORE_FAILURE.
+
+ Malloc only has limited ability to detect failures of MORECORE
+ to supply contiguous space when it says it can. In particular,
+ multithreaded programs that do not use locks may result in
+ rece conditions across calls to MORECORE that result in gaps
+ that cannot be detected as such, and subsequent corruption.
+
+ If you are using this malloc with something other than sbrk (or its
+ emulation) to supply memory regions, you probably want to set
+ MORECORE_CONTIGUOUS as false. As an example, 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
+ #define MORECORE_CONTIGUOUS 0
+
+ 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 * 1024)
+ 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 *) MORECORE_FAILURE;
+ }
+ // save ptrs so they can be freed during cleanup
+ our_os_pools[next_os_pool] = ptr;
+ next_os_pool++;
+ ptr = (void *) ((((CHUNK_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 *) MORECORE_FAILURE;
+ }
+ 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;
+ }
+ }
+
+*/
+
+
+/*
+ --------------------------------------------------------------
+
+ Emulation of sbrk for win32.
+ Donated by J. Walter <Walter@GeNeSys-e.de>.
+ For additional information about this code, and malloc on Win32, see
+ http://www.genesys-e.de/jwalter/
+*/
+
+
+#ifdef WIN32
+
+#ifdef _DEBUG
+/* #define TRACE */
+#endif
+
+/* Support for USE_MALLOC_LOCK */
+#ifdef USE_MALLOC_LOCK
+
+/* Wait for spin lock */
+static int slwait (int *sl) {
+ while (InterlockedCompareExchange ((void **) sl, (void *) 1, (void *) 0) != 0)
+ Sleep (0);
+ return 0;
+}
+
+/* Release spin lock */
+static int slrelease (int *sl) {
+ InterlockedExchange (sl, 0);
+ return 0;
+}
+
+#ifdef NEEDED
+/* Spin lock for emulation code */
+static int g_sl;
+#endif
+
+#endif /* USE_MALLOC_LOCK */
+
+/* getpagesize for windows */
+static long getpagesize (void) {
+ static long g_pagesize = 0;
+ if (! g_pagesize) {
+ SYSTEM_INFO system_info;
+ GetSystemInfo (&system_info);
+ g_pagesize = system_info.dwPageSize;
+ }
+ return g_pagesize;
+}
+static long getregionsize (void) {
+ static long g_regionsize = 0;
+ if (! g_regionsize) {
+ SYSTEM_INFO system_info;
+ GetSystemInfo (&system_info);
+ g_regionsize = system_info.dwAllocationGranularity;
+ }
+ return g_regionsize;
+}
+
+/* A region list entry */
+typedef struct _region_list_entry {
+ void *top_allocated;
+ void *top_committed;
+ void *top_reserved;
+ long reserve_size;
+ struct _region_list_entry *previous;
+} region_list_entry;
+
+/* Allocate and link a region entry in the region list */
+static int region_list_append (region_list_entry **last, void *base_reserved, long reserve_size) {
+ region_list_entry *next =
+ (region_list_entry *)HeapAlloc (GetProcessHeap (), 0, sizeof (region_list_entry));
+ if (! next)
+ return FALSE;
+ next->top_allocated = (char *) base_reserved;
+ next->top_committed = (char *) base_reserved;
+ next->top_reserved = (char *) base_reserved + reserve_size;
+ next->reserve_size = reserve_size;
+ next->previous = *last;
+ *last = next;
+ return TRUE;
+}
+/* Free and unlink the last region entry from the region list */
+static int region_list_remove (region_list_entry **last) {
+ region_list_entry *previous = (*last)->previous;
+ if (! HeapFree (GetProcessHeap (), sizeof (region_list_entry), *last))
+ return FALSE;
+ *last = previous;
+ return TRUE;
+}
+
+#define CEIL(size,to) (((size)+(to)-1)&~((to)-1))
+#define FLOOR(size,to) ((size)&~((to)-1))
+
+#define SBRK_SCALE 0
+/* #define SBRK_SCALE 1 */
+/* #define SBRK_SCALE 2 */
+/* #define SBRK_SCALE 4 */
+
+/* sbrk for windows */
+static void *sbrk (long size) {
+ static long g_pagesize, g_my_pagesize;
+ static long g_regionsize, g_my_regionsize;
+ static region_list_entry *g_last;
+ void *result = (void *) MORECORE_FAILURE;
+#ifdef TRACE
+ printf ("sbrk %d\n", size);
+#endif
+#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
+ /* Wait for spin lock */
+ slwait (&g_sl);
+#endif
+ /* First time initialization */
+ if (! g_pagesize) {
+ g_pagesize = getpagesize ();
+ g_my_pagesize = g_pagesize << SBRK_SCALE;
+ }
+ if (! g_regionsize) {
+ g_regionsize = getregionsize ();
+ g_my_regionsize = g_regionsize << SBRK_SCALE;
+ }
+ if (! g_last) {
+ if (! region_list_append (&g_last, 0, 0))
+ goto sbrk_exit;
+ }
+ /* Assert invariants */
+ assert (g_last);
+ assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_allocated &&
+ g_last->top_allocated <= g_last->top_committed);
+ assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_committed &&
+ g_last->top_committed <= g_last->top_reserved &&
+ (unsigned) g_last->top_committed % g_pagesize == 0);
+ assert ((unsigned) g_last->top_reserved % g_regionsize == 0);
+ assert ((unsigned) g_last->reserve_size % g_regionsize == 0);
+ /* Allocation requested? */
+ if (size >= 0) {
+ /* Allocation size is the requested size */
+ long allocate_size = size;
+ /* Compute the size to commit */
+ long to_commit = (char *) g_last->top_allocated + allocate_size - (char *) g_last->top_committed;
+ /* Do we reach the commit limit? */
+ if (to_commit > 0) {
+ /* Round size to commit */
+ long commit_size = CEIL (to_commit, g_my_pagesize);
+ /* Compute the size to reserve */
+ long to_reserve = (char *) g_last->top_committed + commit_size - (char *) g_last->top_reserved;
+ /* Do we reach the reserve limit? */
+ if (to_reserve > 0) {
+ /* Compute the remaining size to commit in the current region */
+ long remaining_commit_size = (char *) g_last->top_reserved - (char *) g_last->top_committed;
+ if (remaining_commit_size > 0) {
+ /* Assert preconditions */
+ assert ((unsigned) g_last->top_committed % g_pagesize == 0);
+ assert (0 < remaining_commit_size && remaining_commit_size % g_pagesize == 0); {
+ /* Commit this */
+ void *base_committed = VirtualAlloc (g_last->top_committed, remaining_commit_size,
+ MEM_COMMIT, PAGE_READWRITE);
+ /* Check returned pointer for consistency */
+ if (base_committed != g_last->top_committed)
+ goto sbrk_exit;
+ /* Assert postconditions */
+ assert ((unsigned) base_committed % g_pagesize == 0);
+#ifdef TRACE
+ printf ("Commit %p %d\n", base_committed, remaining_commit_size);
+#endif
+ /* Adjust the regions commit top */
+ g_last->top_committed = (char *) base_committed + remaining_commit_size;
+ }
+ } {
+ /* Now we are going to search and reserve. */
+ int contiguous = -1;
+ int found = FALSE;
+ MEMORY_BASIC_INFORMATION memory_info;
+ void *base_reserved;
+ long reserve_size;
+ do {
+ /* Assume contiguous memory */
+ contiguous = TRUE;
+ /* Round size to reserve */
+ reserve_size = CEIL (to_reserve, g_my_regionsize);
+ /* Start with the current region's top */
+ memory_info.BaseAddress = g_last->top_reserved;
+ /* Assert preconditions */
+ assert ((unsigned) memory_info.BaseAddress % g_pagesize == 0);
+ assert (0 < reserve_size && reserve_size % g_regionsize == 0);
+ while (VirtualQuery (memory_info.BaseAddress, &memory_info, sizeof (memory_info))) {
+ /* Assert postconditions */
+ assert ((unsigned) memory_info.BaseAddress % g_pagesize == 0);
+#ifdef TRACE
+ printf ("Query %p %d %s\n", memory_info.BaseAddress, memory_info.RegionSize,
+ memory_info.State == MEM_FREE ? "FREE":
+ (memory_info.State == MEM_RESERVE ? "RESERVED":
+ (memory_info.State == MEM_COMMIT ? "COMMITTED": "?")));
+#endif
+ /* Region is free, well aligned and big enough: we are done */
+ if (memory_info.State == MEM_FREE &&
+ (unsigned) memory_info.BaseAddress % g_regionsize == 0 &&
+ memory_info.RegionSize >= (unsigned) reserve_size) {
+ found = TRUE;
+ break;
+ }
+ /* From now on we can't get contiguous memory! */
+ contiguous = FALSE;
+ /* Recompute size to reserve */
+ reserve_size = CEIL (allocate_size, g_my_regionsize);
+ memory_info.BaseAddress = (char *) memory_info.BaseAddress + memory_info.RegionSize;
+ /* Assert preconditions */
+ assert ((unsigned) memory_info.BaseAddress % g_pagesize == 0);
+ assert (0 < reserve_size && reserve_size % g_regionsize == 0);
+ }
+ /* Search failed? */
+ if (! found)
+ goto sbrk_exit;
+ /* Assert preconditions */
+ assert ((unsigned) memory_info.BaseAddress % g_regionsize == 0);
+ assert (0 < reserve_size && reserve_size % g_regionsize == 0);
+ /* Try to reserve this */
+ base_reserved = VirtualAlloc (memory_info.BaseAddress, reserve_size,
+ MEM_RESERVE, PAGE_NOACCESS);
+ if (! base_reserved) {
+ int rc = GetLastError ();
+ if (rc != ERROR_INVALID_ADDRESS)
+ goto sbrk_exit;
+ }
+ /* A null pointer signals (hopefully) a race condition with another thread. */
+ /* In this case, we try again. */
+ } while (! base_reserved);
+ /* Check returned pointer for consistency */
+ if (memory_info.BaseAddress && base_reserved != memory_info.BaseAddress)
+ goto sbrk_exit;
+ /* Assert postconditions */
+ assert ((unsigned) base_reserved % g_regionsize == 0);
+#ifdef TRACE
+ printf ("Reserve %p %d\n", base_reserved, reserve_size);
+#endif
+ /* Did we get contiguous memory? */
+ if (contiguous) {
+ long start_size = (char *) g_last->top_committed - (char *) g_last->top_allocated;
+ /* Adjust allocation size */
+ allocate_size -= start_size;
+ /* Adjust the regions allocation top */
+ g_last->top_allocated = g_last->top_committed;
+ /* Recompute the size to commit */
+ to_commit = (char *) g_last->top_allocated + allocate_size - (char *) g_last->top_committed;
+ /* Round size to commit */
+ commit_size = CEIL (to_commit, g_my_pagesize);
+ }
+ /* Append the new region to the list */
+ if (! region_list_append (&g_last, base_reserved, reserve_size))
+ goto sbrk_exit;
+ /* Didn't we get contiguous memory? */
+ if (! contiguous) {
+ /* Recompute the size to commit */
+ to_commit = (char *) g_last->top_allocated + allocate_size - (char *) g_last->top_committed;
+ /* Round size to commit */
+ commit_size = CEIL (to_commit, g_my_pagesize);
+ }
+ }
+ }
+ /* Assert preconditions */
+ assert ((unsigned) g_last->top_committed % g_pagesize == 0);
+ assert (0 < commit_size && commit_size % g_pagesize == 0); {
+ /* Commit this */
+ void *base_committed = VirtualAlloc (g_last->top_committed, commit_size,
+ MEM_COMMIT, PAGE_READWRITE);
+ /* Check returned pointer for consistency */
+ if (base_committed != g_last->top_committed)
+ goto sbrk_exit;
+ /* Assert postconditions */
+ assert ((unsigned) base_committed % g_pagesize == 0);
+#ifdef TRACE
+ printf ("Commit %p %d\n", base_committed, commit_size);
+#endif
+ /* Adjust the regions commit top */
+ g_last->top_committed = (char *) base_committed + commit_size;
+ }
+ }
+ /* Adjust the regions allocation top */
+ g_last->top_allocated = (char *) g_last->top_allocated + allocate_size;
+ result = (char *) g_last->top_allocated - size;
+ /* Deallocation requested? */
+ } else if (size < 0) {
+ long deallocate_size = - size;
+ /* As long as we have a region to release */
+ while ((char *) g_last->top_allocated - deallocate_size < (char *) g_last->top_reserved - g_last->reserve_size) {
+ /* Get the size to release */
+ long release_size = g_last->reserve_size;
+ /* Get the base address */
+ void *base_reserved = (char *) g_last->top_reserved - release_size;
+ /* Assert preconditions */
+ assert ((unsigned) base_reserved % g_regionsize == 0);
+ assert (0 < release_size && release_size % g_regionsize == 0); {
+ /* Release this */
+ int rc = VirtualFree (base_reserved, 0,
+ MEM_RELEASE);
+ /* Check returned code for consistency */
+ if (! rc)
+ goto sbrk_exit;
+#ifdef TRACE
+ printf ("Release %p %d\n", base_reserved, release_size);
+#endif
+ }
+ /* Adjust deallocation size */
+ deallocate_size -= (char *) g_last->top_allocated - (char *) base_reserved;
+ /* Remove the old region from the list */
+ if (! region_list_remove (&g_last))
+ goto sbrk_exit;
+ } {
+ /* Compute the size to decommit */
+ long to_decommit = (char *) g_last->top_committed - ((char *) g_last->top_allocated - deallocate_size);
+ if (to_decommit >= g_my_pagesize) {
+ /* Compute the size to decommit */
+ long decommit_size = FLOOR (to_decommit, g_my_pagesize);
+ /* Compute the base address */
+ void *base_committed = (char *) g_last->top_committed - decommit_size;
+ /* Assert preconditions */
+ assert ((unsigned) base_committed % g_pagesize == 0);
+ assert (0 < decommit_size && decommit_size % g_pagesize == 0); {
+ /* Decommit this */
+ int rc = VirtualFree ((char *) base_committed, decommit_size,
+ MEM_DECOMMIT);
+ /* Check returned code for consistency */
+ if (! rc)
+ goto sbrk_exit;
+#ifdef TRACE
+ printf ("Decommit %p %d\n", base_committed, decommit_size);
+#endif
+ }
+ /* Adjust deallocation size and regions commit and allocate top */
+ deallocate_size -= (char *) g_last->top_allocated - (char *) base_committed;
+ g_last->top_committed = base_committed;
+ g_last->top_allocated = base_committed;
+ }
+ }
+ /* Adjust regions allocate top */
+ g_last->top_allocated = (char *) g_last->top_allocated - deallocate_size;
+ /* Check for underflow */
+ if ((char *) g_last->top_reserved - g_last->reserve_size > (char *) g_last->top_allocated ||
+ g_last->top_allocated > g_last->top_committed) {
+ /* Adjust regions allocate top */
+ g_last->top_allocated = (char *) g_last->top_reserved - g_last->reserve_size;
+ goto sbrk_exit;
+ }
+ result = g_last->top_allocated;
+ }
+ /* Assert invariants */
+ assert (g_last);
+ assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_allocated &&
+ g_last->top_allocated <= g_last->top_committed);
+ assert ((char *) g_last->top_reserved - g_last->reserve_size <= (char *) g_last->top_committed &&
+ g_last->top_committed <= g_last->top_reserved &&
+ (unsigned) g_last->top_committed % g_pagesize == 0);
+ assert ((unsigned) g_last->top_reserved % g_regionsize == 0);
+ assert ((unsigned) g_last->reserve_size % g_regionsize == 0);
+
+sbrk_exit:
+#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
+ /* Release spin lock */
+ slrelease (&g_sl);
+#endif
+ return result;
+}
+
+/* mmap for windows */
+static void *mmap (void *ptr, long size, long prot, long type, long handle, long arg) {
+ static long g_pagesize;
+ static long g_regionsize;
+#ifdef TRACE
+ printf ("mmap %d\n", size);
+#endif
+#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
+ /* Wait for spin lock */
+ slwait (&g_sl);
+#endif
+ /* First time initialization */
+ if (! g_pagesize)
+ g_pagesize = getpagesize ();
+ if (! g_regionsize)
+ g_regionsize = getregionsize ();
+ /* Assert preconditions */
+ assert ((unsigned) ptr % g_regionsize == 0);
+ assert (size % g_pagesize == 0);
+ /* Allocate this */
+ ptr = VirtualAlloc (ptr, size,
+ MEM_RESERVE | MEM_COMMIT | MEM_TOP_DOWN, PAGE_READWRITE);
+ if (! ptr) {
+ ptr = (void *) MORECORE_FAILURE;
+ goto mmap_exit;
+ }
+ /* Assert postconditions */
+ assert ((unsigned) ptr % g_regionsize == 0);
+#ifdef TRACE
+ printf ("Commit %p %d\n", ptr, size);
+#endif
+mmap_exit:
+#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
+ /* Release spin lock */
+ slrelease (&g_sl);
+#endif
+ return ptr;
+}
+
+/* munmap for windows */
+static long munmap (void *ptr, long size) {
+ static long g_pagesize;
+ static long g_regionsize;
+ int rc = MUNMAP_FAILURE;
+#ifdef TRACE
+ printf ("munmap %p %d\n", ptr, size);
+#endif
+#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
+ /* Wait for spin lock */
+ slwait (&g_sl);
+#endif
+ /* First time initialization */
+ if (! g_pagesize)
+ g_pagesize = getpagesize ();
+ if (! g_regionsize)
+ g_regionsize = getregionsize ();
+ /* Assert preconditions */
+ assert ((unsigned) ptr % g_regionsize == 0);
+ assert (size % g_pagesize == 0);
+ /* Free this */
+ if (! VirtualFree (ptr, 0,
+ MEM_RELEASE))
+ goto munmap_exit;
+ rc = 0;
+#ifdef TRACE
+ printf ("Release %p %d\n", ptr, size);
+#endif
+munmap_exit:
+#if defined (USE_MALLOC_LOCK) && defined (NEEDED)
+ /* Release spin lock */
+ slrelease (&g_sl);
+#endif
+ return rc;
+}
+
+static void vminfo (CHUNK_SIZE_T *free, CHUNK_SIZE_T *reserved, CHUNK_SIZE_T *committed) {
+ MEMORY_BASIC_INFORMATION memory_info;
+ memory_info.BaseAddress = 0;
+ *free = *reserved = *committed = 0;
+ while (VirtualQuery (memory_info.BaseAddress, &memory_info, sizeof (memory_info))) {
+ switch (memory_info.State) {
+ case MEM_FREE:
+ *free += memory_info.RegionSize;
+ break;
+ case MEM_RESERVE:
+ *reserved += memory_info.RegionSize;
+ break;
+ case MEM_COMMIT:
+ *committed += memory_info.RegionSize;
+ break;
+ }
+ memory_info.BaseAddress = (char *) memory_info.BaseAddress + memory_info.RegionSize;
+ }
+}
+
+#ifdef Q_OS_WINCE
+
+#include <tlhelp32.h>
+
+static int cpuinfo (int whole, CHUNK_SIZE_T *kernel, CHUNK_SIZE_T *user) {
+ if (whole) {
+ __int64 totalKernel64 = 0;
+ __int64 totalUser64 = 0;
+
+ HANDLE threadSnapshot = CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD, GetCurrentProcessId());
+ if (threadSnapshot == INVALID_HANDLE_VALUE) {
+ *kernel = 0;
+ *user = 0;
+ return FALSE;
+ }
+
+ THREADENTRY32 threadEntry;
+ threadEntry.dwSize = sizeof(THREADENTRY32);
+
+ if (!Thread32First(threadSnapshot, &threadEntry)) {
+ *kernel = 0;
+ *user = 0;
+ return FALSE;
+ }
+
+ do {
+ __int64 creation64, exit64, kernel64, user64;
+ HANDLE threadHandle = OpenProcess(0, false, threadEntry.th32ThreadID);
+
+ int rc = GetThreadTimes(threadHandle,
+ (FILETIME *) &creation64,
+ (FILETIME *) &exit64,
+ (FILETIME *) &kernel64,
+ (FILETIME *) &user64);
+
+ CloseHandle(threadHandle);
+
+ if (!rc)
+ continue;
+
+ totalKernel64 += kernel64;
+ totalUser64 += user64;
+ } while (Thread32Next(threadSnapshot, &threadEntry));
+
+ CloseHandle(threadSnapshot);
+
+ *kernel = (CHUNK_SIZE_T) (totalKernel64 / 10000);
+ *user = (CHUNK_SIZE_T) (totalUser64 / 10000);
+ return TRUE;
+ } else {
+ __int64 creation64, exit64, kernel64, user64;
+ int rc = GetThreadTimes (GetCurrentThread (),
+ (FILETIME *) &creation64,
+ (FILETIME *) &exit64,
+ (FILETIME *) &kernel64,
+ (FILETIME *) &user64);
+ if (! rc) {
+ *kernel = 0;
+ *user = 0;
+ return FALSE;
+ }
+ *kernel = (CHUNK_SIZE_T) (kernel64 / 10000);
+ *user = (CHUNK_SIZE_T) (user64 / 10000);
+ return TRUE;
+ }
+}
+#else
+static int cpuinfo (int whole, CHUNK_SIZE_T *kernel, CHUNK_SIZE_T *user) {
+ if (whole) {
+ __int64 creation64, exit64, kernel64, user64;
+ int rc = GetProcessTimes (GetCurrentProcess (),
+ (FILETIME *) &creation64,
+ (FILETIME *) &exit64,
+ (FILETIME *) &kernel64,
+ (FILETIME *) &user64);
+ if (! rc) {
+ *kernel = 0;
+ *user = 0;
+ return FALSE;
+ }
+ *kernel = (CHUNK_SIZE_T) (kernel64 / 10000);
+ *user = (CHUNK_SIZE_T) (user64 / 10000);
+ return TRUE;
+ } else {
+ __int64 creation64, exit64, kernel64, user64;
+ int rc = GetThreadTimes (GetCurrentThread (),
+ (FILETIME *) &creation64,
+ (FILETIME *) &exit64,
+ (FILETIME *) &kernel64,
+ (FILETIME *) &user64);
+ if (! rc) {
+ *kernel = 0;
+ *user = 0;
+ return FALSE;
+ }
+ *kernel = (CHUNK_SIZE_T) (kernel64 / 10000);
+ *user = (CHUNK_SIZE_T) (user64 / 10000);
+ return TRUE;
+ }
+}
+#endif
+
+#endif /* WIN32 */
+
+/* ------------------------------------------------------------
+History:
+ 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.)
+
+*/