| OLD | NEW |
|---|
| (Empty) |
| 1 /* | |
| 2 ** 2001 September 15 | |
| 3 ** | |
| 4 ** The author disclaims copyright to this source code. In place of | |
| 5 ** a legal notice, here is a blessing: | |
| 6 ** | |
| 7 ** May you do good and not evil. | |
| 8 ** May you find forgiveness for yourself and forgive others. | |
| 9 ** May you share freely, never taking more than you give. | |
| 10 ** | |
| 11 ************************************************************************* | |
| 12 ** | |
| 13 ** Memory allocation functions used throughout sqlite. | |
| 14 */ | |
| 15 #include "sqliteInt.h" | |
| 16 #include <stdarg.h> | |
| 17 | |
| 18 /* | |
| 19 ** Attempt to release up to n bytes of non-essential memory currently | |
| 20 ** held by SQLite. An example of non-essential memory is memory used to | |
| 21 ** cache database pages that are not currently in use. | |
| 22 */ | |
| 23 int sqlite3_release_memory(int n){ | |
| 24 #ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT | |
| 25 return sqlite3PcacheReleaseMemory(n); | |
| 26 #else | |
| 27 /* IMPLEMENTATION-OF: R-34391-24921 The sqlite3_release_memory() routine | |
| 28 ** is a no-op returning zero if SQLite is not compiled with | |
| 29 ** SQLITE_ENABLE_MEMORY_MANAGEMENT. */ | |
| 30 UNUSED_PARAMETER(n); | |
| 31 return 0; | |
| 32 #endif | |
| 33 } | |
| 34 | |
| 35 /* | |
| 36 ** An instance of the following object records the location of | |
| 37 ** each unused scratch buffer. | |
| 38 */ | |
| 39 typedef struct ScratchFreeslot { | |
| 40 struct ScratchFreeslot *pNext; /* Next unused scratch buffer */ | |
| 41 } ScratchFreeslot; | |
| 42 | |
| 43 /* | |
| 44 ** State information local to the memory allocation subsystem. | |
| 45 */ | |
| 46 static SQLITE_WSD struct Mem0Global { | |
| 47 sqlite3_mutex *mutex; /* Mutex to serialize access */ | |
| 48 | |
| 49 /* | |
| 50 ** The alarm callback and its arguments. The mem0.mutex lock will | |
| 51 ** be held while the callback is running. Recursive calls into | |
| 52 ** the memory subsystem are allowed, but no new callbacks will be | |
| 53 ** issued. | |
| 54 */ | |
| 55 sqlite3_int64 alarmThreshold; | |
| 56 void (*alarmCallback)(void*, sqlite3_int64,int); | |
| 57 void *alarmArg; | |
| 58 | |
| 59 /* | |
| 60 ** Pointers to the end of sqlite3GlobalConfig.pScratch memory | |
| 61 ** (so that a range test can be used to determine if an allocation | |
| 62 ** being freed came from pScratch) and a pointer to the list of | |
| 63 ** unused scratch allocations. | |
| 64 */ | |
| 65 void *pScratchEnd; | |
| 66 ScratchFreeslot *pScratchFree; | |
| 67 u32 nScratchFree; | |
| 68 | |
| 69 /* | |
| 70 ** True if heap is nearly "full" where "full" is defined by the | |
| 71 ** sqlite3_soft_heap_limit() setting. | |
| 72 */ | |
| 73 int nearlyFull; | |
| 74 } mem0 = { 0, 0, 0, 0, 0, 0, 0, 0 }; | |
| 75 | |
| 76 #define mem0 GLOBAL(struct Mem0Global, mem0) | |
| 77 | |
| 78 /* | |
| 79 ** This routine runs when the memory allocator sees that the | |
| 80 ** total memory allocation is about to exceed the soft heap | |
| 81 ** limit. | |
| 82 */ | |
| 83 static void softHeapLimitEnforcer( | |
| 84 void *NotUsed, | |
| 85 sqlite3_int64 NotUsed2, | |
| 86 int allocSize | |
| 87 ){ | |
| 88 UNUSED_PARAMETER2(NotUsed, NotUsed2); | |
| 89 sqlite3_release_memory(allocSize); | |
| 90 } | |
| 91 | |
| 92 /* | |
| 93 ** Change the alarm callback | |
| 94 */ | |
| 95 static int sqlite3MemoryAlarm( | |
| 96 void(*xCallback)(void *pArg, sqlite3_int64 used,int N), | |
| 97 void *pArg, | |
| 98 sqlite3_int64 iThreshold | |
| 99 ){ | |
| 100 int nUsed; | |
| 101 sqlite3_mutex_enter(mem0.mutex); | |
| 102 mem0.alarmCallback = xCallback; | |
| 103 mem0.alarmArg = pArg; | |
| 104 mem0.alarmThreshold = iThreshold; | |
| 105 nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED); | |
| 106 mem0.nearlyFull = (iThreshold>0 && iThreshold<=nUsed); | |
| 107 sqlite3_mutex_leave(mem0.mutex); | |
| 108 return SQLITE_OK; | |
| 109 } | |
| 110 | |
| 111 #ifndef SQLITE_OMIT_DEPRECATED | |
| 112 /* | |
| 113 ** Deprecated external interface. Internal/core SQLite code | |
| 114 ** should call sqlite3MemoryAlarm. | |
| 115 */ | |
| 116 int sqlite3_memory_alarm( | |
| 117 void(*xCallback)(void *pArg, sqlite3_int64 used,int N), | |
| 118 void *pArg, | |
| 119 sqlite3_int64 iThreshold | |
| 120 ){ | |
| 121 return sqlite3MemoryAlarm(xCallback, pArg, iThreshold); | |
| 122 } | |
| 123 #endif | |
| 124 | |
| 125 /* | |
| 126 ** Set the soft heap-size limit for the library. Passing a zero or | |
| 127 ** negative value indicates no limit. | |
| 128 */ | |
| 129 sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 n){ | |
| 130 sqlite3_int64 priorLimit; | |
| 131 sqlite3_int64 excess; | |
| 132 #ifndef SQLITE_OMIT_AUTOINIT | |
| 133 int rc = sqlite3_initialize(); | |
| 134 if( rc ) return -1; | |
| 135 #endif | |
| 136 sqlite3_mutex_enter(mem0.mutex); | |
| 137 priorLimit = mem0.alarmThreshold; | |
| 138 sqlite3_mutex_leave(mem0.mutex); | |
| 139 if( n<0 ) return priorLimit; | |
| 140 if( n>0 ){ | |
| 141 sqlite3MemoryAlarm(softHeapLimitEnforcer, 0, n); | |
| 142 }else{ | |
| 143 sqlite3MemoryAlarm(0, 0, 0); | |
| 144 } | |
| 145 excess = sqlite3_memory_used() - n; | |
| 146 if( excess>0 ) sqlite3_release_memory((int)(excess & 0x7fffffff)); | |
| 147 return priorLimit; | |
| 148 } | |
| 149 void sqlite3_soft_heap_limit(int n){ | |
| 150 if( n<0 ) n = 0; | |
| 151 sqlite3_soft_heap_limit64(n); | |
| 152 } | |
| 153 | |
| 154 /* | |
| 155 ** Initialize the memory allocation subsystem. | |
| 156 */ | |
| 157 int sqlite3MallocInit(void){ | |
| 158 if( sqlite3GlobalConfig.m.xMalloc==0 ){ | |
| 159 sqlite3MemSetDefault(); | |
| 160 } | |
| 161 memset(&mem0, 0, sizeof(mem0)); | |
| 162 if( sqlite3GlobalConfig.bCoreMutex ){ | |
| 163 mem0.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM); | |
| 164 } | |
| 165 if( sqlite3GlobalConfig.pScratch && sqlite3GlobalConfig.szScratch>=100 | |
| 166 && sqlite3GlobalConfig.nScratch>0 ){ | |
| 167 int i, n, sz; | |
| 168 ScratchFreeslot *pSlot; | |
| 169 sz = ROUNDDOWN8(sqlite3GlobalConfig.szScratch); | |
| 170 sqlite3GlobalConfig.szScratch = sz; | |
| 171 pSlot = (ScratchFreeslot*)sqlite3GlobalConfig.pScratch; | |
| 172 n = sqlite3GlobalConfig.nScratch; | |
| 173 mem0.pScratchFree = pSlot; | |
| 174 mem0.nScratchFree = n; | |
| 175 for(i=0; i<n-1; i++){ | |
| 176 pSlot->pNext = (ScratchFreeslot*)(sz+(char*)pSlot); | |
| 177 pSlot = pSlot->pNext; | |
| 178 } | |
| 179 pSlot->pNext = 0; | |
| 180 mem0.pScratchEnd = (void*)&pSlot[1]; | |
| 181 }else{ | |
| 182 mem0.pScratchEnd = 0; | |
| 183 sqlite3GlobalConfig.pScratch = 0; | |
| 184 sqlite3GlobalConfig.szScratch = 0; | |
| 185 sqlite3GlobalConfig.nScratch = 0; | |
| 186 } | |
| 187 if( sqlite3GlobalConfig.pPage==0 || sqlite3GlobalConfig.szPage<512 | |
| 188 || sqlite3GlobalConfig.nPage<1 ){ | |
| 189 sqlite3GlobalConfig.pPage = 0; | |
| 190 sqlite3GlobalConfig.szPage = 0; | |
| 191 sqlite3GlobalConfig.nPage = 0; | |
| 192 } | |
| 193 return sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData); | |
| 194 } | |
| 195 | |
| 196 /* | |
| 197 ** Return true if the heap is currently under memory pressure - in other | |
| 198 ** words if the amount of heap used is close to the limit set by | |
| 199 ** sqlite3_soft_heap_limit(). | |
| 200 */ | |
| 201 int sqlite3HeapNearlyFull(void){ | |
| 202 return mem0.nearlyFull; | |
| 203 } | |
| 204 | |
| 205 /* | |
| 206 ** Deinitialize the memory allocation subsystem. | |
| 207 */ | |
| 208 void sqlite3MallocEnd(void){ | |
| 209 if( sqlite3GlobalConfig.m.xShutdown ){ | |
| 210 sqlite3GlobalConfig.m.xShutdown(sqlite3GlobalConfig.m.pAppData); | |
| 211 } | |
| 212 memset(&mem0, 0, sizeof(mem0)); | |
| 213 } | |
| 214 | |
| 215 /* | |
| 216 ** Return the amount of memory currently checked out. | |
| 217 */ | |
| 218 sqlite3_int64 sqlite3_memory_used(void){ | |
| 219 int n, mx; | |
| 220 sqlite3_int64 res; | |
| 221 sqlite3_status(SQLITE_STATUS_MEMORY_USED, &n, &mx, 0); | |
| 222 res = (sqlite3_int64)n; /* Work around bug in Borland C. Ticket #3216 */ | |
| 223 return res; | |
| 224 } | |
| 225 | |
| 226 /* | |
| 227 ** Return the maximum amount of memory that has ever been | |
| 228 ** checked out since either the beginning of this process | |
| 229 ** or since the most recent reset. | |
| 230 */ | |
| 231 sqlite3_int64 sqlite3_memory_highwater(int resetFlag){ | |
| 232 int n, mx; | |
| 233 sqlite3_int64 res; | |
| 234 sqlite3_status(SQLITE_STATUS_MEMORY_USED, &n, &mx, resetFlag); | |
| 235 res = (sqlite3_int64)mx; /* Work around bug in Borland C. Ticket #3216 */ | |
| 236 return res; | |
| 237 } | |
| 238 | |
| 239 /* | |
| 240 ** Trigger the alarm | |
| 241 */ | |
| 242 static void sqlite3MallocAlarm(int nByte){ | |
| 243 void (*xCallback)(void*,sqlite3_int64,int); | |
| 244 sqlite3_int64 nowUsed; | |
| 245 void *pArg; | |
| 246 if( mem0.alarmCallback==0 ) return; | |
| 247 xCallback = mem0.alarmCallback; | |
| 248 nowUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED); | |
| 249 pArg = mem0.alarmArg; | |
| 250 mem0.alarmCallback = 0; | |
| 251 sqlite3_mutex_leave(mem0.mutex); | |
| 252 xCallback(pArg, nowUsed, nByte); | |
| 253 sqlite3_mutex_enter(mem0.mutex); | |
| 254 mem0.alarmCallback = xCallback; | |
| 255 mem0.alarmArg = pArg; | |
| 256 } | |
| 257 | |
| 258 /* | |
| 259 ** Do a memory allocation with statistics and alarms. Assume the | |
| 260 ** lock is already held. | |
| 261 */ | |
| 262 static int mallocWithAlarm(int n, void **pp){ | |
| 263 int nFull; | |
| 264 void *p; | |
| 265 assert( sqlite3_mutex_held(mem0.mutex) ); | |
| 266 nFull = sqlite3GlobalConfig.m.xRoundup(n); | |
| 267 sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, n); | |
| 268 if( mem0.alarmCallback!=0 ){ | |
| 269 int nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED); | |
| 270 if( nUsed >= mem0.alarmThreshold - nFull ){ | |
| 271 mem0.nearlyFull = 1; | |
| 272 sqlite3MallocAlarm(nFull); | |
| 273 }else{ | |
| 274 mem0.nearlyFull = 0; | |
| 275 } | |
| 276 } | |
| 277 p = sqlite3GlobalConfig.m.xMalloc(nFull); | |
| 278 #ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT | |
| 279 if( p==0 && mem0.alarmCallback ){ | |
| 280 sqlite3MallocAlarm(nFull); | |
| 281 p = sqlite3GlobalConfig.m.xMalloc(nFull); | |
| 282 } | |
| 283 #endif | |
| 284 if( p ){ | |
| 285 nFull = sqlite3MallocSize(p); | |
| 286 sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nFull); | |
| 287 sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, 1); | |
| 288 } | |
| 289 *pp = p; | |
| 290 return nFull; | |
| 291 } | |
| 292 | |
| 293 /* | |
| 294 ** Allocate memory. This routine is like sqlite3_malloc() except that it | |
| 295 ** assumes the memory subsystem has already been initialized. | |
| 296 */ | |
| 297 void *sqlite3Malloc(u64 n){ | |
| 298 void *p; | |
| 299 if( n==0 || n>=0x7fffff00 ){ | |
| 300 /* A memory allocation of a number of bytes which is near the maximum | |
| 301 ** signed integer value might cause an integer overflow inside of the | |
| 302 ** xMalloc(). Hence we limit the maximum size to 0x7fffff00, giving | |
| 303 ** 255 bytes of overhead. SQLite itself will never use anything near | |
| 304 ** this amount. The only way to reach the limit is with sqlite3_malloc() */ | |
| 305 p = 0; | |
| 306 }else if( sqlite3GlobalConfig.bMemstat ){ | |
| 307 sqlite3_mutex_enter(mem0.mutex); | |
| 308 mallocWithAlarm((int)n, &p); | |
| 309 sqlite3_mutex_leave(mem0.mutex); | |
| 310 }else{ | |
| 311 p = sqlite3GlobalConfig.m.xMalloc((int)n); | |
| 312 } | |
| 313 assert( EIGHT_BYTE_ALIGNMENT(p) ); /* IMP: R-11148-40995 */ | |
| 314 return p; | |
| 315 } | |
| 316 | |
| 317 /* | |
| 318 ** This version of the memory allocation is for use by the application. | |
| 319 ** First make sure the memory subsystem is initialized, then do the | |
| 320 ** allocation. | |
| 321 */ | |
| 322 void *sqlite3_malloc(int n){ | |
| 323 #ifndef SQLITE_OMIT_AUTOINIT | |
| 324 if( sqlite3_initialize() ) return 0; | |
| 325 #endif | |
| 326 return n<=0 ? 0 : sqlite3Malloc(n); | |
| 327 } | |
| 328 void *sqlite3_malloc64(sqlite3_uint64 n){ | |
| 329 #ifndef SQLITE_OMIT_AUTOINIT | |
| 330 if( sqlite3_initialize() ) return 0; | |
| 331 #endif | |
| 332 return sqlite3Malloc(n); | |
| 333 } | |
| 334 | |
| 335 /* | |
| 336 ** Each thread may only have a single outstanding allocation from | |
| 337 ** xScratchMalloc(). We verify this constraint in the single-threaded | |
| 338 ** case by setting scratchAllocOut to 1 when an allocation | |
| 339 ** is outstanding clearing it when the allocation is freed. | |
| 340 */ | |
| 341 #if SQLITE_THREADSAFE==0 && !defined(NDEBUG) | |
| 342 static int scratchAllocOut = 0; | |
| 343 #endif | |
| 344 | |
| 345 | |
| 346 /* | |
| 347 ** Allocate memory that is to be used and released right away. | |
| 348 ** This routine is similar to alloca() in that it is not intended | |
| 349 ** for situations where the memory might be held long-term. This | |
| 350 ** routine is intended to get memory to old large transient data | |
| 351 ** structures that would not normally fit on the stack of an | |
| 352 ** embedded processor. | |
| 353 */ | |
| 354 void *sqlite3ScratchMalloc(int n){ | |
| 355 void *p; | |
| 356 assert( n>0 ); | |
| 357 | |
| 358 sqlite3_mutex_enter(mem0.mutex); | |
| 359 sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n); | |
| 360 if( mem0.nScratchFree && sqlite3GlobalConfig.szScratch>=n ){ | |
| 361 p = mem0.pScratchFree; | |
| 362 mem0.pScratchFree = mem0.pScratchFree->pNext; | |
| 363 mem0.nScratchFree--; | |
| 364 sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, 1); | |
| 365 sqlite3_mutex_leave(mem0.mutex); | |
| 366 }else{ | |
| 367 sqlite3_mutex_leave(mem0.mutex); | |
| 368 p = sqlite3Malloc(n); | |
| 369 if( sqlite3GlobalConfig.bMemstat && p ){ | |
| 370 sqlite3_mutex_enter(mem0.mutex); | |
| 371 sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, sqlite3MallocSize(p)); | |
| 372 sqlite3_mutex_leave(mem0.mutex); | |
| 373 } | |
| 374 sqlite3MemdebugSetType(p, MEMTYPE_SCRATCH); | |
| 375 } | |
| 376 assert( sqlite3_mutex_notheld(mem0.mutex) ); | |
| 377 | |
| 378 | |
| 379 #if SQLITE_THREADSAFE==0 && !defined(NDEBUG) | |
| 380 /* Verify that no more than two scratch allocations per thread | |
| 381 ** are outstanding at one time. (This is only checked in the | |
| 382 ** single-threaded case since checking in the multi-threaded case | |
| 383 ** would be much more complicated.) */ | |
| 384 assert( scratchAllocOut<=1 ); | |
| 385 if( p ) scratchAllocOut++; | |
| 386 #endif | |
| 387 | |
| 388 return p; | |
| 389 } | |
| 390 void sqlite3ScratchFree(void *p){ | |
| 391 if( p ){ | |
| 392 | |
| 393 #if SQLITE_THREADSAFE==0 && !defined(NDEBUG) | |
| 394 /* Verify that no more than two scratch allocation per thread | |
| 395 ** is outstanding at one time. (This is only checked in the | |
| 396 ** single-threaded case since checking in the multi-threaded case | |
| 397 ** would be much more complicated.) */ | |
| 398 assert( scratchAllocOut>=1 && scratchAllocOut<=2 ); | |
| 399 scratchAllocOut--; | |
| 400 #endif | |
| 401 | |
| 402 if( p>=sqlite3GlobalConfig.pScratch && p<mem0.pScratchEnd ){ | |
| 403 /* Release memory from the SQLITE_CONFIG_SCRATCH allocation */ | |
| 404 ScratchFreeslot *pSlot; | |
| 405 pSlot = (ScratchFreeslot*)p; | |
| 406 sqlite3_mutex_enter(mem0.mutex); | |
| 407 pSlot->pNext = mem0.pScratchFree; | |
| 408 mem0.pScratchFree = pSlot; | |
| 409 mem0.nScratchFree++; | |
| 410 assert( mem0.nScratchFree <= (u32)sqlite3GlobalConfig.nScratch ); | |
| 411 sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, -1); | |
| 412 sqlite3_mutex_leave(mem0.mutex); | |
| 413 }else{ | |
| 414 /* Release memory back to the heap */ | |
| 415 assert( sqlite3MemdebugHasType(p, MEMTYPE_SCRATCH) ); | |
| 416 assert( sqlite3MemdebugNoType(p, ~MEMTYPE_SCRATCH) ); | |
| 417 sqlite3MemdebugSetType(p, MEMTYPE_HEAP); | |
| 418 if( sqlite3GlobalConfig.bMemstat ){ | |
| 419 int iSize = sqlite3MallocSize(p); | |
| 420 sqlite3_mutex_enter(mem0.mutex); | |
| 421 sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, -iSize); | |
| 422 sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -iSize); | |
| 423 sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1); | |
| 424 sqlite3GlobalConfig.m.xFree(p); | |
| 425 sqlite3_mutex_leave(mem0.mutex); | |
| 426 }else{ | |
| 427 sqlite3GlobalConfig.m.xFree(p); | |
| 428 } | |
| 429 } | |
| 430 } | |
| 431 } | |
| 432 | |
| 433 /* | |
| 434 ** TRUE if p is a lookaside memory allocation from db | |
| 435 */ | |
| 436 #ifndef SQLITE_OMIT_LOOKASIDE | |
| 437 static int isLookaside(sqlite3 *db, void *p){ | |
| 438 return p>=db->lookaside.pStart && p<db->lookaside.pEnd; | |
| 439 } | |
| 440 #else | |
| 441 #define isLookaside(A,B) 0 | |
| 442 #endif | |
| 443 | |
| 444 /* | |
| 445 ** Return the size of a memory allocation previously obtained from | |
| 446 ** sqlite3Malloc() or sqlite3_malloc(). | |
| 447 */ | |
| 448 int sqlite3MallocSize(void *p){ | |
| 449 assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) ); | |
| 450 return sqlite3GlobalConfig.m.xSize(p); | |
| 451 } | |
| 452 int sqlite3DbMallocSize(sqlite3 *db, void *p){ | |
| 453 if( db==0 ){ | |
| 454 assert( sqlite3MemdebugNoType(p, ~MEMTYPE_HEAP) ); | |
| 455 assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) ); | |
| 456 return sqlite3MallocSize(p); | |
| 457 }else{ | |
| 458 assert( sqlite3_mutex_held(db->mutex) ); | |
| 459 if( isLookaside(db, p) ){ | |
| 460 return db->lookaside.sz; | |
| 461 }else{ | |
| 462 assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) ); | |
| 463 assert( sqlite3MemdebugNoType(p, ~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) ); | |
| 464 return sqlite3GlobalConfig.m.xSize(p); | |
| 465 } | |
| 466 } | |
| 467 } | |
| 468 sqlite3_uint64 sqlite3_msize(void *p){ | |
| 469 assert( sqlite3MemdebugNoType(p, ~MEMTYPE_HEAP) ); | |
| 470 assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) ); | |
| 471 return (sqlite3_uint64)sqlite3GlobalConfig.m.xSize(p); | |
| 472 } | |
| 473 | |
| 474 /* | |
| 475 ** Free memory previously obtained from sqlite3Malloc(). | |
| 476 */ | |
| 477 void sqlite3_free(void *p){ | |
| 478 if( p==0 ) return; /* IMP: R-49053-54554 */ | |
| 479 assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) ); | |
| 480 assert( sqlite3MemdebugNoType(p, ~MEMTYPE_HEAP) ); | |
| 481 if( sqlite3GlobalConfig.bMemstat ){ | |
| 482 sqlite3_mutex_enter(mem0.mutex); | |
| 483 sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, -sqlite3MallocSize(p)); | |
| 484 sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1); | |
| 485 sqlite3GlobalConfig.m.xFree(p); | |
| 486 sqlite3_mutex_leave(mem0.mutex); | |
| 487 }else{ | |
| 488 sqlite3GlobalConfig.m.xFree(p); | |
| 489 } | |
| 490 } | |
| 491 | |
| 492 /* | |
| 493 ** Add the size of memory allocation "p" to the count in | |
| 494 ** *db->pnBytesFreed. | |
| 495 */ | |
| 496 static SQLITE_NOINLINE void measureAllocationSize(sqlite3 *db, void *p){ | |
| 497 *db->pnBytesFreed += sqlite3DbMallocSize(db,p); | |
| 498 } | |
| 499 | |
| 500 /* | |
| 501 ** Free memory that might be associated with a particular database | |
| 502 ** connection. | |
| 503 */ | |
| 504 void sqlite3DbFree(sqlite3 *db, void *p){ | |
| 505 assert( db==0 || sqlite3_mutex_held(db->mutex) ); | |
| 506 if( p==0 ) return; | |
| 507 if( db ){ | |
| 508 if( db->pnBytesFreed ){ | |
| 509 measureAllocationSize(db, p); | |
| 510 return; | |
| 511 } | |
| 512 if( isLookaside(db, p) ){ | |
| 513 LookasideSlot *pBuf = (LookasideSlot*)p; | |
| 514 #if SQLITE_DEBUG | |
| 515 /* Trash all content in the buffer being freed */ | |
| 516 memset(p, 0xaa, db->lookaside.sz); | |
| 517 #endif | |
| 518 pBuf->pNext = db->lookaside.pFree; | |
| 519 db->lookaside.pFree = pBuf; | |
| 520 db->lookaside.nOut--; | |
| 521 return; | |
| 522 } | |
| 523 } | |
| 524 assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) ); | |
| 525 assert( sqlite3MemdebugNoType(p, ~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) ); | |
| 526 assert( db!=0 || sqlite3MemdebugNoType(p, MEMTYPE_LOOKASIDE) ); | |
| 527 sqlite3MemdebugSetType(p, MEMTYPE_HEAP); | |
| 528 sqlite3_free(p); | |
| 529 } | |
| 530 | |
| 531 /* | |
| 532 ** Change the size of an existing memory allocation | |
| 533 */ | |
| 534 void *sqlite3Realloc(void *pOld, u64 nBytes){ | |
| 535 int nOld, nNew, nDiff; | |
| 536 void *pNew; | |
| 537 assert( sqlite3MemdebugHasType(pOld, MEMTYPE_HEAP) ); | |
| 538 assert( sqlite3MemdebugNoType(pOld, ~MEMTYPE_HEAP) ); | |
| 539 if( pOld==0 ){ | |
| 540 return sqlite3Malloc(nBytes); /* IMP: R-04300-56712 */ | |
| 541 } | |
| 542 if( nBytes==0 ){ | |
| 543 sqlite3_free(pOld); /* IMP: R-26507-47431 */ | |
| 544 return 0; | |
| 545 } | |
| 546 if( nBytes>=0x7fffff00 ){ | |
| 547 /* The 0x7ffff00 limit term is explained in comments on sqlite3Malloc() */ | |
| 548 return 0; | |
| 549 } | |
| 550 nOld = sqlite3MallocSize(pOld); | |
| 551 /* IMPLEMENTATION-OF: R-46199-30249 SQLite guarantees that the second | |
| 552 ** argument to xRealloc is always a value returned by a prior call to | |
| 553 ** xRoundup. */ | |
| 554 nNew = sqlite3GlobalConfig.m.xRoundup((int)nBytes); | |
| 555 if( nOld==nNew ){ | |
| 556 pNew = pOld; | |
| 557 }else if( sqlite3GlobalConfig.bMemstat ){ | |
| 558 sqlite3_mutex_enter(mem0.mutex); | |
| 559 sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, (int)nBytes); | |
| 560 nDiff = nNew - nOld; | |
| 561 if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED) >= | |
| 562 mem0.alarmThreshold-nDiff ){ | |
| 563 sqlite3MallocAlarm(nDiff); | |
| 564 } | |
| 565 pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew); | |
| 566 if( pNew==0 && mem0.alarmCallback ){ | |
| 567 sqlite3MallocAlarm((int)nBytes); | |
| 568 pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew); | |
| 569 } | |
| 570 if( pNew ){ | |
| 571 nNew = sqlite3MallocSize(pNew); | |
| 572 sqlite3StatusAdd(SQLITE_STATUS_MEMORY_USED, nNew-nOld); | |
| 573 } | |
| 574 sqlite3_mutex_leave(mem0.mutex); | |
| 575 }else{ | |
| 576 pNew = sqlite3GlobalConfig.m.xRealloc(pOld, nNew); | |
| 577 } | |
| 578 assert( EIGHT_BYTE_ALIGNMENT(pNew) ); /* IMP: R-11148-40995 */ | |
| 579 return pNew; | |
| 580 } | |
| 581 | |
| 582 /* | |
| 583 ** The public interface to sqlite3Realloc. Make sure that the memory | |
| 584 ** subsystem is initialized prior to invoking sqliteRealloc. | |
| 585 */ | |
| 586 void *sqlite3_realloc(void *pOld, int n){ | |
| 587 #ifndef SQLITE_OMIT_AUTOINIT | |
| 588 if( sqlite3_initialize() ) return 0; | |
| 589 #endif | |
| 590 if( n<0 ) n = 0; /* IMP: R-26507-47431 */ | |
| 591 return sqlite3Realloc(pOld, n); | |
| 592 } | |
| 593 void *sqlite3_realloc64(void *pOld, sqlite3_uint64 n){ | |
| 594 #ifndef SQLITE_OMIT_AUTOINIT | |
| 595 if( sqlite3_initialize() ) return 0; | |
| 596 #endif | |
| 597 return sqlite3Realloc(pOld, n); | |
| 598 } | |
| 599 | |
| 600 | |
| 601 /* | |
| 602 ** Allocate and zero memory. | |
| 603 */ | |
| 604 void *sqlite3MallocZero(u64 n){ | |
| 605 void *p = sqlite3Malloc(n); | |
| 606 if( p ){ | |
| 607 memset(p, 0, (size_t)n); | |
| 608 } | |
| 609 return p; | |
| 610 } | |
| 611 | |
| 612 /* | |
| 613 ** Allocate and zero memory. If the allocation fails, make | |
| 614 ** the mallocFailed flag in the connection pointer. | |
| 615 */ | |
| 616 void *sqlite3DbMallocZero(sqlite3 *db, u64 n){ | |
| 617 void *p = sqlite3DbMallocRaw(db, n); | |
| 618 if( p ){ | |
| 619 memset(p, 0, (size_t)n); | |
| 620 } | |
| 621 return p; | |
| 622 } | |
| 623 | |
| 624 /* | |
| 625 ** Allocate and zero memory. If the allocation fails, make | |
| 626 ** the mallocFailed flag in the connection pointer. | |
| 627 ** | |
| 628 ** If db!=0 and db->mallocFailed is true (indicating a prior malloc | |
| 629 ** failure on the same database connection) then always return 0. | |
| 630 ** Hence for a particular database connection, once malloc starts | |
| 631 ** failing, it fails consistently until mallocFailed is reset. | |
| 632 ** This is an important assumption. There are many places in the | |
| 633 ** code that do things like this: | |
| 634 ** | |
| 635 ** int *a = (int*)sqlite3DbMallocRaw(db, 100); | |
| 636 ** int *b = (int*)sqlite3DbMallocRaw(db, 200); | |
| 637 ** if( b ) a[10] = 9; | |
| 638 ** | |
| 639 ** In other words, if a subsequent malloc (ex: "b") worked, it is assumed | |
| 640 ** that all prior mallocs (ex: "a") worked too. | |
| 641 */ | |
| 642 void *sqlite3DbMallocRaw(sqlite3 *db, u64 n){ | |
| 643 void *p; | |
| 644 assert( db==0 || sqlite3_mutex_held(db->mutex) ); | |
| 645 assert( db==0 || db->pnBytesFreed==0 ); | |
| 646 #ifndef SQLITE_OMIT_LOOKASIDE | |
| 647 if( db ){ | |
| 648 LookasideSlot *pBuf; | |
| 649 if( db->mallocFailed ){ | |
| 650 return 0; | |
| 651 } | |
| 652 if( db->lookaside.bEnabled ){ | |
| 653 if( n>db->lookaside.sz ){ | |
| 654 db->lookaside.anStat[1]++; | |
| 655 }else if( (pBuf = db->lookaside.pFree)==0 ){ | |
| 656 db->lookaside.anStat[2]++; | |
| 657 }else{ | |
| 658 db->lookaside.pFree = pBuf->pNext; | |
| 659 db->lookaside.nOut++; | |
| 660 db->lookaside.anStat[0]++; | |
| 661 if( db->lookaside.nOut>db->lookaside.mxOut ){ | |
| 662 db->lookaside.mxOut = db->lookaside.nOut; | |
| 663 } | |
| 664 return (void*)pBuf; | |
| 665 } | |
| 666 } | |
| 667 } | |
| 668 #else | |
| 669 if( db && db->mallocFailed ){ | |
| 670 return 0; | |
| 671 } | |
| 672 #endif | |
| 673 p = sqlite3Malloc(n); | |
| 674 if( !p && db ){ | |
| 675 db->mallocFailed = 1; | |
| 676 } | |
| 677 sqlite3MemdebugSetType(p, | |
| 678 (db && db->lookaside.bEnabled) ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP); | |
| 679 return p; | |
| 680 } | |
| 681 | |
| 682 /* | |
| 683 ** Resize the block of memory pointed to by p to n bytes. If the | |
| 684 ** resize fails, set the mallocFailed flag in the connection object. | |
| 685 */ | |
| 686 void *sqlite3DbRealloc(sqlite3 *db, void *p, u64 n){ | |
| 687 void *pNew = 0; | |
| 688 assert( db!=0 ); | |
| 689 assert( sqlite3_mutex_held(db->mutex) ); | |
| 690 if( db->mallocFailed==0 ){ | |
| 691 if( p==0 ){ | |
| 692 return sqlite3DbMallocRaw(db, n); | |
| 693 } | |
| 694 if( isLookaside(db, p) ){ | |
| 695 if( n<=db->lookaside.sz ){ | |
| 696 return p; | |
| 697 } | |
| 698 pNew = sqlite3DbMallocRaw(db, n); | |
| 699 if( pNew ){ | |
| 700 memcpy(pNew, p, db->lookaside.sz); | |
| 701 sqlite3DbFree(db, p); | |
| 702 } | |
| 703 }else{ | |
| 704 assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) ); | |
| 705 assert( sqlite3MemdebugNoType(p, ~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) ); | |
| 706 sqlite3MemdebugSetType(p, MEMTYPE_HEAP); | |
| 707 pNew = sqlite3_realloc64(p, n); | |
| 708 if( !pNew ){ | |
| 709 db->mallocFailed = 1; | |
| 710 } | |
| 711 sqlite3MemdebugSetType(pNew, | |
| 712 (db->lookaside.bEnabled ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP)); | |
| 713 } | |
| 714 } | |
| 715 return pNew; | |
| 716 } | |
| 717 | |
| 718 /* | |
| 719 ** Attempt to reallocate p. If the reallocation fails, then free p | |
| 720 ** and set the mallocFailed flag in the database connection. | |
| 721 */ | |
| 722 void *sqlite3DbReallocOrFree(sqlite3 *db, void *p, u64 n){ | |
| 723 void *pNew; | |
| 724 pNew = sqlite3DbRealloc(db, p, n); | |
| 725 if( !pNew ){ | |
| 726 sqlite3DbFree(db, p); | |
| 727 } | |
| 728 return pNew; | |
| 729 } | |
| 730 | |
| 731 /* | |
| 732 ** Make a copy of a string in memory obtained from sqliteMalloc(). These | |
| 733 ** functions call sqlite3MallocRaw() directly instead of sqliteMalloc(). This | |
| 734 ** is because when memory debugging is turned on, these two functions are | |
| 735 ** called via macros that record the current file and line number in the | |
| 736 ** ThreadData structure. | |
| 737 */ | |
| 738 char *sqlite3DbStrDup(sqlite3 *db, const char *z){ | |
| 739 char *zNew; | |
| 740 size_t n; | |
| 741 if( z==0 ){ | |
| 742 return 0; | |
| 743 } | |
| 744 n = sqlite3Strlen30(z) + 1; | |
| 745 assert( (n&0x7fffffff)==n ); | |
| 746 zNew = sqlite3DbMallocRaw(db, (int)n); | |
| 747 if( zNew ){ | |
| 748 memcpy(zNew, z, n); | |
| 749 } | |
| 750 return zNew; | |
| 751 } | |
| 752 char *sqlite3DbStrNDup(sqlite3 *db, const char *z, u64 n){ | |
| 753 char *zNew; | |
| 754 if( z==0 ){ | |
| 755 return 0; | |
| 756 } | |
| 757 assert( (n&0x7fffffff)==n ); | |
| 758 zNew = sqlite3DbMallocRaw(db, n+1); | |
| 759 if( zNew ){ | |
| 760 memcpy(zNew, z, (size_t)n); | |
| 761 zNew[n] = 0; | |
| 762 } | |
| 763 return zNew; | |
| 764 } | |
| 765 | |
| 766 /* | |
| 767 ** Create a string from the zFromat argument and the va_list that follows. | |
| 768 ** Store the string in memory obtained from sqliteMalloc() and make *pz | |
| 769 ** point to that string. | |
| 770 */ | |
| 771 void sqlite3SetString(char **pz, sqlite3 *db, const char *zFormat, ...){ | |
| 772 va_list ap; | |
| 773 char *z; | |
| 774 | |
| 775 va_start(ap, zFormat); | |
| 776 z = sqlite3VMPrintf(db, zFormat, ap); | |
| 777 va_end(ap); | |
| 778 sqlite3DbFree(db, *pz); | |
| 779 *pz = z; | |
| 780 } | |
| 781 | |
| 782 /* | |
| 783 ** Take actions at the end of an API call to indicate an OOM error | |
| 784 */ | |
| 785 static SQLITE_NOINLINE int apiOomError(sqlite3 *db){ | |
| 786 db->mallocFailed = 0; | |
| 787 sqlite3Error(db, SQLITE_NOMEM); | |
| 788 return SQLITE_NOMEM; | |
| 789 } | |
| 790 | |
| 791 /* | |
| 792 ** This function must be called before exiting any API function (i.e. | |
| 793 ** returning control to the user) that has called sqlite3_malloc or | |
| 794 ** sqlite3_realloc. | |
| 795 ** | |
| 796 ** The returned value is normally a copy of the second argument to this | |
| 797 ** function. However, if a malloc() failure has occurred since the previous | |
| 798 ** invocation SQLITE_NOMEM is returned instead. | |
| 799 ** | |
| 800 ** If the first argument, db, is not NULL and a malloc() error has occurred, | |
| 801 ** then the connection error-code (the value returned by sqlite3_errcode()) | |
| 802 ** is set to SQLITE_NOMEM. | |
| 803 */ | |
| 804 int sqlite3ApiExit(sqlite3* db, int rc){ | |
| 805 /* If the db handle is not NULL, then we must hold the connection handle | |
| 806 ** mutex here. Otherwise the read (and possible write) of db->mallocFailed | |
| 807 ** is unsafe, as is the call to sqlite3Error(). | |
| 808 */ | |
| 809 assert( !db || sqlite3_mutex_held(db->mutex) ); | |
| 810 if( db==0 ) return rc & 0xff; | |
| 811 if( db->mallocFailed || rc==SQLITE_IOERR_NOMEM ){ | |
| 812 return apiOomError(db); | |
| 813 } | |
| 814 return rc & db->errMask; | |
| 815 } | |
| OLD | NEW |
|---|
Chromium Code Reviews
Issue 2363173002:
[sqlite] Remove obsolete reference version 3.8.7.4. (Closed)
