diff -r 5f8e5adbbed9 -r 29cda98b007e engine/sqlite/src/malloc.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/engine/sqlite/src/malloc.cpp Thu Feb 25 14:29:19 2010 +0000 @@ -0,0 +1,241 @@ +/* +** 2001 September 15 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** Memory allocation functions used throughout sqlite. +** +** +** $Id: malloc.cpp 1282 2008-11-13 09:31:33Z LarsPson $ +*/ +#include "sqliteInt.h" +#include +#include + +/* +** This routine runs when the memory allocator sees that the +** total memory allocation is about to exceed the soft heap +** limit. +*/ +static void softHeapLimitEnforcer( + void *NotUsed, + sqlite3_int64 inUse, + int allocSize +){ + sqlite3_release_memory(allocSize); +} + +/* +** Set the soft heap-size limit for the current thread. Passing a +** zero or negative value indicates no limit. +*/ +EXPORT_C void sqlite3_soft_heap_limit(int n){ + sqlite3_uint64 iLimit; + int overage; + if( n<0 ){ + iLimit = 0; + }else{ + iLimit = n; + } + if( iLimit>0 ){ + sqlite3_memory_alarm(softHeapLimitEnforcer, 0, iLimit); + }else{ + sqlite3_memory_alarm(0, 0, 0); + } + overage = sqlite3_memory_used() - n; + if( overage>0 ){ + sqlite3_release_memory(overage); + } +} + +/* +** Release memory held by SQLite instances created by the current thread. +*/ +EXPORT_C int sqlite3_release_memory(int n){ +#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT + return sqlite3PagerReleaseMemory(n); +#else + return SQLITE_OK; +#endif +} + + +/* +** Allocate and zero memory. +*/ +void *sqlite3MallocZero(unsigned n){ + + void *p = sqlite3_malloc(n); + if( p ){ + memset(p, 0, n); + } + + return p; +} + +/* +** Allocate and zero memory. If the allocation fails, make +** the mallocFailed flag in the connection pointer. +*/ +void *sqlite3DbMallocZero(sqlite3 *db, unsigned n){ + void *p = sqlite3DbMallocRaw(db, n); + if( p ){ + memset(p, 0, n); + } + return p; +} + +/* +** Allocate and zero memory. If the allocation fails, make +** the mallocFailed flag in the connection pointer. +*/ +void *sqlite3DbMallocRaw(sqlite3 *db, unsigned n){ + void *p = 0; + if( !db || db->mallocFailed==0 ){ + p = sqlite3_malloc(n); + if( !p && db ){ + db->mallocFailed = 1; + } + } + return p; +} + +/* +** Resize the block of memory pointed to by p to n bytes. If the +** resize fails, set the mallocFailed flag inthe connection object. +*/ +void *sqlite3DbRealloc(sqlite3 *db, void *p, int n){ + void *pNew = 0; + if( db->mallocFailed==0 ){ + pNew = sqlite3_realloc(p, n); + if( !pNew ){ + db->mallocFailed = 1; + } + } + return pNew; +} + +/* +** Attempt to reallocate p. If the reallocation fails, then free p +** and set the mallocFailed flag in the database connection. +*/ +void *sqlite3DbReallocOrFree(sqlite3 *db, void *p, int n){ + void *pNew; + pNew = sqlite3DbRealloc(db, p, n); + if( !pNew ){ + sqlite3_free(p); + } + return pNew; +} + +/* +** Make a copy of a string in memory obtained from sqliteMalloc(). These +** functions call sqlite3MallocRaw() directly instead of sqliteMalloc(). This +** is because when memory debugging is turned on, these two functions are +** called via macros that record the current file and line number in the +** ThreadData structure. +*/ +char *sqlite3StrDup(const char *z){ + char *zNew; + int n; + if( z==0 ) return 0; + n = strlen(z)+1; + zNew = (char*)sqlite3_malloc(n); + if( zNew ) memcpy(zNew, z, n); + return zNew; +} +char *sqlite3StrNDup(const char *z, int n){ + char *zNew; + if( z==0 ) return 0; + zNew = (char*)sqlite3_malloc(n+1); + if( zNew ){ + memcpy(zNew, z, n); + zNew[n] = 0; + } + return zNew; +} + +char *sqlite3DbStrDup(sqlite3 *db, const char *z){ + char *zNew = sqlite3StrDup(z); + if( z && !zNew ){ + db->mallocFailed = 1; + } + return zNew; +} +char *sqlite3DbStrNDup(sqlite3 *db, const char *z, int n){ + char *zNew = sqlite3StrNDup(z, n); + if( z && !zNew ){ + db->mallocFailed = 1; + } + return zNew; +} + +/* +** Create a string from the 2nd and subsequent arguments (up to the +** first NULL argument), store the string in memory obtained from +** sqliteMalloc() and make the pointer indicated by the 1st argument +** point to that string. The 1st argument must either be NULL or +** point to memory obtained from sqliteMalloc(). +*/ +void sqlite3SetString(char **pz, ...){ + va_list ap; + int nByte; + const char *z; + char *zResult; + + assert( pz!=0 ); + nByte = 1; + va_start(ap, pz); + while( (z = va_arg(ap, const char*))!=0 ){ + nByte += strlen(z); + } + va_end(ap); + sqlite3_free(*pz); + *pz = zResult = (char*)sqlite3_malloc(nByte); + if( zResult==0 ){ + return; + } + *zResult = 0; + va_start(ap, pz); + while( (z = va_arg(ap, const char*))!=0 ){ + int n = strlen(z); + memcpy(zResult, z, n); + zResult += n; + } + zResult[0] = 0; + va_end(ap); +} + + +/* +** This function must be called before exiting any API function (i.e. +** returning control to the user) that has called sqlite3_malloc or +** sqlite3_realloc. +** +** The returned value is normally a copy of the second argument to this +** function. However, if a malloc() failure has occured since the previous +** invocation SQLITE_NOMEM is returned instead. +** +** If the first argument, db, is not NULL and a malloc() error has occured, +** then the connection error-code (the value returned by sqlite3_errcode()) +** is set to SQLITE_NOMEM. +*/ +int sqlite3ApiExit(sqlite3* db, int rc){ + /* If the db handle is not NULL, then we must hold the connection handle + ** mutex here. Otherwise the read (and possible write) of db->mallocFailed + ** is unsafe, as is the call to sqlite3Error(). + */ + assert( !db || sqlite3_mutex_held(db->mutex) ); + if( db && db->mallocFailed ){ + sqlite3Error(db, SQLITE_NOMEM, 0); + db->mallocFailed = 0; + rc = SQLITE_NOMEM; + } + return rc & (db ? db->errMask : 0xff); +}