/*
** 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.c,v 1.6 2007/08/16 10:09:03 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <stdarg.h>
#include <ctype.h>
/*
** Set the soft heap-size limit for the current thread. Passing a negative
** value indicates no limit.
*/
void sqlite3_soft_heap_limit(int n){
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
ThreadData *pTd = sqlite3ThreadData();
if( pTd ){
pTd->nSoftHeapLimit = n;
}
sqlite3ReleaseThreadData();
#endif
}
/*
** Release memory held by SQLite instances created by the current thread.
*/
int sqlite3_release_memory(int n){
#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) && !defined(SQLITE_OMIT_DISKIO)
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 = sqlite3_malloc(n);
if( p ){
memset(p, 0, n);
}else{
db->mallocFailed = 1;
}
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 = sqlite3_malloc(n);
if( !p ){
db->mallocFailed = 1;
}
return p;
}
/*
** 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 = sqlite3_realloc(p, n);
if( !pNew ){
sqlite3_free(p);
db->mallocFailed = 1;
}
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 = 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 = 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 = 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( db && db->mallocFailed ){
sqlite3Error(db, SQLITE_NOMEM, 0);
db->mallocFailed = 0;
rc = SQLITE_NOMEM;
}
return rc & (db ? db->errMask : 0xff);
}
#ifdef SQLITE_MEMDEBUG
/*
** This function sets a flag in the thread-specific-data structure that will
** cause an assert to fail if sqliteMalloc() or sqliteRealloc() is called.
*/
#if 0
void sqlite3MallocDisallow(){
#if 0
assert( sqlite3_mallocDisallowed>=0 );
sqlite3_mallocDisallowed++;
#endif
}
/*
** This function clears the flag set in the thread-specific-data structure set
** by sqlite3MallocDisallow().
*/
void sqlite3MallocAllow(){
#if 0
assert( sqlite3_mallocDisallowed>0 );
sqlite3_mallocDisallowed--;
#endif
}
#endif
#endif