1/* 2** 2007 October 14 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** This file contains the C functions that implement a memory 13** allocation subsystem for use by SQLite. 14** 15** This version of the memory allocation subsystem omits all 16** use of malloc(). The SQLite user supplies a block of memory 17** before calling sqlite3_initialize() from which allocations 18** are made and returned by the xMalloc() and xRealloc() 19** implementations. Once sqlite3_initialize() has been called, 20** the amount of memory available to SQLite is fixed and cannot 21** be changed. 22** 23** This version of the memory allocation subsystem is included 24** in the build only if SQLITE_ENABLE_MEMSYS3 is defined. 25*/ 26#include "sqliteInt.h" 27 28/* 29** This version of the memory allocator is only built into the library 30** SQLITE_ENABLE_MEMSYS3 is defined. Defining this symbol does not 31** mean that the library will use a memory-pool by default, just that 32** it is available. The mempool allocator is activated by calling 33** sqlite3_config(). 34*/ 35#ifdef SQLITE_ENABLE_MEMSYS3 36 37/* 38** Maximum size (in Mem3Blocks) of a "small" chunk. 39*/ 40#define MX_SMALL 10 41 42 43/* 44** Number of freelist hash slots 45*/ 46#define N_HASH 61 47 48/* 49** A memory allocation (also called a "chunk") consists of two or 50** more blocks where each block is 8 bytes. The first 8 bytes are 51** a header that is not returned to the user. 52** 53** A chunk is two or more blocks that is either checked out or 54** free. The first block has format u.hdr. u.hdr.size4x is 4 times the 55** size of the allocation in blocks if the allocation is free. 56** The u.hdr.size4x&1 bit is true if the chunk is checked out and 57** false if the chunk is on the freelist. The u.hdr.size4x&2 bit 58** is true if the previous chunk is checked out and false if the 59** previous chunk is free. The u.hdr.prevSize field is the size of 60** the previous chunk in blocks if the previous chunk is on the 61** freelist. If the previous chunk is checked out, then 62** u.hdr.prevSize can be part of the data for that chunk and should 63** not be read or written. 64** 65** We often identify a chunk by its index in mem3.aPool[]. When 66** this is done, the chunk index refers to the second block of 67** the chunk. In this way, the first chunk has an index of 1. 68** A chunk index of 0 means "no such chunk" and is the equivalent 69** of a NULL pointer. 70** 71** The second block of free chunks is of the form u.list. The 72** two fields form a double-linked list of chunks of related sizes. 73** Pointers to the head of the list are stored in mem3.aiSmall[] 74** for smaller chunks and mem3.aiHash[] for larger chunks. 75** 76** The second block of a chunk is user data if the chunk is checked 77** out. If a chunk is checked out, the user data may extend into 78** the u.hdr.prevSize value of the following chunk. 79*/ 80typedef struct Mem3Block Mem3Block; 81struct Mem3Block { 82 union { 83 struct { 84 u32 prevSize; /* Size of previous chunk in Mem3Block elements */ 85 u32 size4x; /* 4x the size of current chunk in Mem3Block elements */ 86 } hdr; 87 struct { 88 u32 next; /* Index in mem3.aPool[] of next free chunk */ 89 u32 prev; /* Index in mem3.aPool[] of previous free chunk */ 90 } list; 91 } u; 92}; 93 94/* 95** All of the static variables used by this module are collected 96** into a single structure named "mem3". This is to keep the 97** static variables organized and to reduce namespace pollution 98** when this module is combined with other in the amalgamation. 99*/ 100static SQLITE_WSD struct Mem3Global { 101 /* 102 ** Memory available for allocation. nPool is the size of the array 103 ** (in Mem3Blocks) pointed to by aPool less 2. 104 */ 105 u32 nPool; 106 Mem3Block *aPool; 107 108 /* 109 ** True if we are evaluating an out-of-memory callback. 110 */ 111 int alarmBusy; 112 113 /* 114 ** Mutex to control access to the memory allocation subsystem. 115 */ 116 sqlite3_mutex *mutex; 117 118 /* 119 ** The minimum amount of free space that we have seen. 120 */ 121 u32 mnMaster; 122 123 /* 124 ** iMaster is the index of the master chunk. Most new allocations 125 ** occur off of this chunk. szMaster is the size (in Mem3Blocks) 126 ** of the current master. iMaster is 0 if there is not master chunk. 127 ** The master chunk is not in either the aiHash[] or aiSmall[]. 128 */ 129 u32 iMaster; 130 u32 szMaster; 131 132 /* 133 ** Array of lists of free blocks according to the block size 134 ** for smaller chunks, or a hash on the block size for larger 135 ** chunks. 136 */ 137 u32 aiSmall[MX_SMALL-1]; /* For sizes 2 through MX_SMALL, inclusive */ 138 u32 aiHash[N_HASH]; /* For sizes MX_SMALL+1 and larger */ 139} mem3 = { 97535575 }; 140 141#define mem3 GLOBAL(struct Mem3Global, mem3) 142 143/* 144** Unlink the chunk at mem3.aPool[i] from list it is currently 145** on. *pRoot is the list that i is a member of. 146*/ 147static void memsys3UnlinkFromList(u32 i, u32 *pRoot){ 148 u32 next = mem3.aPool[i].u.list.next; 149 u32 prev = mem3.aPool[i].u.list.prev; 150 assert( sqlite3_mutex_held(mem3.mutex) ); 151 if( prev==0 ){ 152 *pRoot = next; 153 }else{ 154 mem3.aPool[prev].u.list.next = next; 155 } 156 if( next ){ 157 mem3.aPool[next].u.list.prev = prev; 158 } 159 mem3.aPool[i].u.list.next = 0; 160 mem3.aPool[i].u.list.prev = 0; 161} 162 163/* 164** Unlink the chunk at index i from 165** whatever list is currently a member of. 166*/ 167static void memsys3Unlink(u32 i){ 168 u32 size, hash; 169 assert( sqlite3_mutex_held(mem3.mutex) ); 170 assert( (mem3.aPool[i-1].u.hdr.size4x & 1)==0 ); 171 assert( i>=1 ); 172 size = mem3.aPool[i-1].u.hdr.size4x/4; 173 assert( size==mem3.aPool[i+size-1].u.hdr.prevSize ); 174 assert( size>=2 ); 175 if( size <= MX_SMALL ){ 176 memsys3UnlinkFromList(i, &mem3.aiSmall[size-2]); 177 }else{ 178 hash = size % N_HASH; 179 memsys3UnlinkFromList(i, &mem3.aiHash[hash]); 180 } 181} 182 183/* 184** Link the chunk at mem3.aPool[i] so that is on the list rooted 185** at *pRoot. 186*/ 187static void memsys3LinkIntoList(u32 i, u32 *pRoot){ 188 assert( sqlite3_mutex_held(mem3.mutex) ); 189 mem3.aPool[i].u.list.next = *pRoot; 190 mem3.aPool[i].u.list.prev = 0; 191 if( *pRoot ){ 192 mem3.aPool[*pRoot].u.list.prev = i; 193 } 194 *pRoot = i; 195} 196 197/* 198** Link the chunk at index i into either the appropriate 199** small chunk list, or into the large chunk hash table. 200*/ 201static void memsys3Link(u32 i){ 202 u32 size, hash; 203 assert( sqlite3_mutex_held(mem3.mutex) ); 204 assert( i>=1 ); 205 assert( (mem3.aPool[i-1].u.hdr.size4x & 1)==0 ); 206 size = mem3.aPool[i-1].u.hdr.size4x/4; 207 assert( size==mem3.aPool[i+size-1].u.hdr.prevSize ); 208 assert( size>=2 ); 209 if( size <= MX_SMALL ){ 210 memsys3LinkIntoList(i, &mem3.aiSmall[size-2]); 211 }else{ 212 hash = size % N_HASH; 213 memsys3LinkIntoList(i, &mem3.aiHash[hash]); 214 } 215} 216 217/* 218** If the STATIC_MEM mutex is not already held, obtain it now. The mutex 219** will already be held (obtained by code in malloc.c) if 220** sqlite3GlobalConfig.bMemStat is true. 221*/ 222static void memsys3Enter(void){ 223 if( sqlite3GlobalConfig.bMemstat==0 && mem3.mutex==0 ){ 224 mem3.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM); 225 } 226 sqlite3_mutex_enter(mem3.mutex); 227} 228static void memsys3Leave(void){ 229 sqlite3_mutex_leave(mem3.mutex); 230} 231 232/* 233** Called when we are unable to satisfy an allocation of nBytes. 234*/ 235static void memsys3OutOfMemory(int nByte){ 236 if( !mem3.alarmBusy ){ 237 mem3.alarmBusy = 1; 238 assert( sqlite3_mutex_held(mem3.mutex) ); 239 sqlite3_mutex_leave(mem3.mutex); 240 sqlite3_release_memory(nByte); 241 sqlite3_mutex_enter(mem3.mutex); 242 mem3.alarmBusy = 0; 243 } 244} 245 246 247/* 248** Chunk i is a free chunk that has been unlinked. Adjust its 249** size parameters for check-out and return a pointer to the 250** user portion of the chunk. 251*/ 252static void *memsys3Checkout(u32 i, u32 nBlock){ 253 u32 x; 254 assert( sqlite3_mutex_held(mem3.mutex) ); 255 assert( i>=1 ); 256 assert( mem3.aPool[i-1].u.hdr.size4x/4==nBlock ); 257 assert( mem3.aPool[i+nBlock-1].u.hdr.prevSize==nBlock ); 258 x = mem3.aPool[i-1].u.hdr.size4x; 259 mem3.aPool[i-1].u.hdr.size4x = nBlock*4 | 1 | (x&2); 260 mem3.aPool[i+nBlock-1].u.hdr.prevSize = nBlock; 261 mem3.aPool[i+nBlock-1].u.hdr.size4x |= 2; 262 return &mem3.aPool[i]; 263} 264 265/* 266** Carve a piece off of the end of the mem3.iMaster free chunk. 267** Return a pointer to the new allocation. Or, if the master chunk 268** is not large enough, return 0. 269*/ 270static void *memsys3FromMaster(u32 nBlock){ 271 assert( sqlite3_mutex_held(mem3.mutex) ); 272 assert( mem3.szMaster>=nBlock ); 273 if( nBlock>=mem3.szMaster-1 ){ 274 /* Use the entire master */ 275 void *p = memsys3Checkout(mem3.iMaster, mem3.szMaster); 276 mem3.iMaster = 0; 277 mem3.szMaster = 0; 278 mem3.mnMaster = 0; 279 return p; 280 }else{ 281 /* Split the master block. Return the tail. */ 282 u32 newi, x; 283 newi = mem3.iMaster + mem3.szMaster - nBlock; 284 assert( newi > mem3.iMaster+1 ); 285 mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = nBlock; 286 mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x |= 2; 287 mem3.aPool[newi-1].u.hdr.size4x = nBlock*4 + 1; 288 mem3.szMaster -= nBlock; 289 mem3.aPool[newi-1].u.hdr.prevSize = mem3.szMaster; 290 x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2; 291 mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x; 292 if( mem3.szMaster < mem3.mnMaster ){ 293 mem3.mnMaster = mem3.szMaster; 294 } 295 return (void*)&mem3.aPool[newi]; 296 } 297} 298 299/* 300** *pRoot is the head of a list of free chunks of the same size 301** or same size hash. In other words, *pRoot is an entry in either 302** mem3.aiSmall[] or mem3.aiHash[]. 303** 304** This routine examines all entries on the given list and tries 305** to coalesce each entries with adjacent free chunks. 306** 307** If it sees a chunk that is larger than mem3.iMaster, it replaces 308** the current mem3.iMaster with the new larger chunk. In order for 309** this mem3.iMaster replacement to work, the master chunk must be 310** linked into the hash tables. That is not the normal state of 311** affairs, of course. The calling routine must link the master 312** chunk before invoking this routine, then must unlink the (possibly 313** changed) master chunk once this routine has finished. 314*/ 315static void memsys3Merge(u32 *pRoot){ 316 u32 iNext, prev, size, i, x; 317 318 assert( sqlite3_mutex_held(mem3.mutex) ); 319 for(i=*pRoot; i>0; i=iNext){ 320 iNext = mem3.aPool[i].u.list.next; 321 size = mem3.aPool[i-1].u.hdr.size4x; 322 assert( (size&1)==0 ); 323 if( (size&2)==0 ){ 324 memsys3UnlinkFromList(i, pRoot); 325 assert( i > mem3.aPool[i-1].u.hdr.prevSize ); 326 prev = i - mem3.aPool[i-1].u.hdr.prevSize; 327 if( prev==iNext ){ 328 iNext = mem3.aPool[prev].u.list.next; 329 } 330 memsys3Unlink(prev); 331 size = i + size/4 - prev; 332 x = mem3.aPool[prev-1].u.hdr.size4x & 2; 333 mem3.aPool[prev-1].u.hdr.size4x = size*4 | x; 334 mem3.aPool[prev+size-1].u.hdr.prevSize = size; 335 memsys3Link(prev); 336 i = prev; 337 }else{ 338 size /= 4; 339 } 340 if( size>mem3.szMaster ){ 341 mem3.iMaster = i; 342 mem3.szMaster = size; 343 } 344 } 345} 346 347/* 348** Return a block of memory of at least nBytes in size. 349** Return NULL if unable. 350** 351** This function assumes that the necessary mutexes, if any, are 352** already held by the caller. Hence "Unsafe". 353*/ 354static void *memsys3MallocUnsafe(int nByte){ 355 u32 i; 356 u32 nBlock; 357 u32 toFree; 358 359 assert( sqlite3_mutex_held(mem3.mutex) ); 360 assert( sizeof(Mem3Block)==8 ); 361 if( nByte<=12 ){ 362 nBlock = 2; 363 }else{ 364 nBlock = (nByte + 11)/8; 365 } 366 assert( nBlock>=2 ); 367 368 /* STEP 1: 369 ** Look for an entry of the correct size in either the small 370 ** chunk table or in the large chunk hash table. This is 371 ** successful most of the time (about 9 times out of 10). 372 */ 373 if( nBlock <= MX_SMALL ){ 374 i = mem3.aiSmall[nBlock-2]; 375 if( i>0 ){ 376 memsys3UnlinkFromList(i, &mem3.aiSmall[nBlock-2]); 377 return memsys3Checkout(i, nBlock); 378 } 379 }else{ 380 int hash = nBlock % N_HASH; 381 for(i=mem3.aiHash[hash]; i>0; i=mem3.aPool[i].u.list.next){ 382 if( mem3.aPool[i-1].u.hdr.size4x/4==nBlock ){ 383 memsys3UnlinkFromList(i, &mem3.aiHash[hash]); 384 return memsys3Checkout(i, nBlock); 385 } 386 } 387 } 388 389 /* STEP 2: 390 ** Try to satisfy the allocation by carving a piece off of the end 391 ** of the master chunk. This step usually works if step 1 fails. 392 */ 393 if( mem3.szMaster>=nBlock ){ 394 return memsys3FromMaster(nBlock); 395 } 396 397 398 /* STEP 3: 399 ** Loop through the entire memory pool. Coalesce adjacent free 400 ** chunks. Recompute the master chunk as the largest free chunk. 401 ** Then try again to satisfy the allocation by carving a piece off 402 ** of the end of the master chunk. This step happens very 403 ** rarely (we hope!) 404 */ 405 for(toFree=nBlock*16; toFree<(mem3.nPool*16); toFree *= 2){ 406 memsys3OutOfMemory(toFree); 407 if( mem3.iMaster ){ 408 memsys3Link(mem3.iMaster); 409 mem3.iMaster = 0; 410 mem3.szMaster = 0; 411 } 412 for(i=0; i<N_HASH; i++){ 413 memsys3Merge(&mem3.aiHash[i]); 414 } 415 for(i=0; i<MX_SMALL-1; i++){ 416 memsys3Merge(&mem3.aiSmall[i]); 417 } 418 if( mem3.szMaster ){ 419 memsys3Unlink(mem3.iMaster); 420 if( mem3.szMaster>=nBlock ){ 421 return memsys3FromMaster(nBlock); 422 } 423 } 424 } 425 426 /* If none of the above worked, then we fail. */ 427 return 0; 428} 429 430/* 431** Free an outstanding memory allocation. 432** 433** This function assumes that the necessary mutexes, if any, are 434** already held by the caller. Hence "Unsafe". 435*/ 436void memsys3FreeUnsafe(void *pOld){ 437 Mem3Block *p = (Mem3Block*)pOld; 438 int i; 439 u32 size, x; 440 assert( sqlite3_mutex_held(mem3.mutex) ); 441 assert( p>mem3.aPool && p<&mem3.aPool[mem3.nPool] ); 442 i = p - mem3.aPool; 443 assert( (mem3.aPool[i-1].u.hdr.size4x&1)==1 ); 444 size = mem3.aPool[i-1].u.hdr.size4x/4; 445 assert( i+size<=mem3.nPool+1 ); 446 mem3.aPool[i-1].u.hdr.size4x &= ~1; 447 mem3.aPool[i+size-1].u.hdr.prevSize = size; 448 mem3.aPool[i+size-1].u.hdr.size4x &= ~2; 449 memsys3Link(i); 450 451 /* Try to expand the master using the newly freed chunk */ 452 if( mem3.iMaster ){ 453 while( (mem3.aPool[mem3.iMaster-1].u.hdr.size4x&2)==0 ){ 454 size = mem3.aPool[mem3.iMaster-1].u.hdr.prevSize; 455 mem3.iMaster -= size; 456 mem3.szMaster += size; 457 memsys3Unlink(mem3.iMaster); 458 x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2; 459 mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x; 460 mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = mem3.szMaster; 461 } 462 x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2; 463 while( (mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x&1)==0 ){ 464 memsys3Unlink(mem3.iMaster+mem3.szMaster); 465 mem3.szMaster += mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x/4; 466 mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x; 467 mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = mem3.szMaster; 468 } 469 } 470} 471 472/* 473** Return the size of an outstanding allocation, in bytes. The 474** size returned omits the 8-byte header overhead. This only 475** works for chunks that are currently checked out. 476*/ 477static int memsys3Size(void *p){ 478 Mem3Block *pBlock; 479 if( p==0 ) return 0; 480 pBlock = (Mem3Block*)p; 481 assert( (pBlock[-1].u.hdr.size4x&1)!=0 ); 482 return (pBlock[-1].u.hdr.size4x&~3)*2 - 4; 483} 484 485/* 486** Round up a request size to the next valid allocation size. 487*/ 488static int memsys3Roundup(int n){ 489 if( n<=12 ){ 490 return 12; 491 }else{ 492 return ((n+11)&~7) - 4; 493 } 494} 495 496/* 497** Allocate nBytes of memory. 498*/ 499static void *memsys3Malloc(int nBytes){ 500 sqlite3_int64 *p; 501 assert( nBytes>0 ); /* malloc.c filters out 0 byte requests */ 502 memsys3Enter(); 503 p = memsys3MallocUnsafe(nBytes); 504 memsys3Leave(); 505 return (void*)p; 506} 507 508/* 509** Free memory. 510*/ 511void memsys3Free(void *pPrior){ 512 assert( pPrior ); 513 memsys3Enter(); 514 memsys3FreeUnsafe(pPrior); 515 memsys3Leave(); 516} 517 518/* 519** Change the size of an existing memory allocation 520*/ 521void *memsys3Realloc(void *pPrior, int nBytes){ 522 int nOld; 523 void *p; 524 if( pPrior==0 ){ 525 return sqlite3_malloc(nBytes); 526 } 527 if( nBytes<=0 ){ 528 sqlite3_free(pPrior); 529 return 0; 530 } 531 nOld = memsys3Size(pPrior); 532 if( nBytes<=nOld && nBytes>=nOld-128 ){ 533 return pPrior; 534 } 535 memsys3Enter(); 536 p = memsys3MallocUnsafe(nBytes); 537 if( p ){ 538 if( nOld<nBytes ){ 539 memcpy(p, pPrior, nOld); 540 }else{ 541 memcpy(p, pPrior, nBytes); 542 } 543 memsys3FreeUnsafe(pPrior); 544 } 545 memsys3Leave(); 546 return p; 547} 548 549/* 550** Initialize this module. 551*/ 552static int memsys3Init(void *NotUsed){ 553 UNUSED_PARAMETER(NotUsed); 554 if( !sqlite3GlobalConfig.pHeap ){ 555 return SQLITE_ERROR; 556 } 557 558 /* Store a pointer to the memory block in global structure mem3. */ 559 assert( sizeof(Mem3Block)==8 ); 560 mem3.aPool = (Mem3Block *)sqlite3GlobalConfig.pHeap; 561 mem3.nPool = (sqlite3GlobalConfig.nHeap / sizeof(Mem3Block)) - 2; 562 563 /* Initialize the master block. */ 564 mem3.szMaster = mem3.nPool; 565 mem3.mnMaster = mem3.szMaster; 566 mem3.iMaster = 1; 567 mem3.aPool[0].u.hdr.size4x = (mem3.szMaster<<2) + 2; 568 mem3.aPool[mem3.nPool].u.hdr.prevSize = mem3.nPool; 569 mem3.aPool[mem3.nPool].u.hdr.size4x = 1; 570 571 return SQLITE_OK; 572} 573 574/* 575** Deinitialize this module. 576*/ 577static void memsys3Shutdown(void *NotUsed){ 578 UNUSED_PARAMETER(NotUsed); 579 mem3.mutex = 0; 580 return; 581} 582 583 584 585/* 586** Open the file indicated and write a log of all unfreed memory 587** allocations into that log. 588*/ 589void sqlite3Memsys3Dump(const char *zFilename){ 590#ifdef SQLITE_DEBUG 591 FILE *out; 592 u32 i, j; 593 u32 size; 594 if( zFilename==0 || zFilename[0]==0 ){ 595 out = stdout; 596 }else{ 597 out = fopen(zFilename, "w"); 598 if( out==0 ){ 599 fprintf(stderr, "** Unable to output memory debug output log: %s **\n", 600 zFilename); 601 return; 602 } 603 } 604 memsys3Enter(); 605 fprintf(out, "CHUNKS:\n"); 606 for(i=1; i<=mem3.nPool; i+=size/4){ 607 size = mem3.aPool[i-1].u.hdr.size4x; 608 if( size/4<=1 ){ 609 fprintf(out, "%p size error\n", &mem3.aPool[i]); 610 assert( 0 ); 611 break; 612 } 613 if( (size&1)==0 && mem3.aPool[i+size/4-1].u.hdr.prevSize!=size/4 ){ 614 fprintf(out, "%p tail size does not match\n", &mem3.aPool[i]); 615 assert( 0 ); 616 break; 617 } 618 if( ((mem3.aPool[i+size/4-1].u.hdr.size4x&2)>>1)!=(size&1) ){ 619 fprintf(out, "%p tail checkout bit is incorrect\n", &mem3.aPool[i]); 620 assert( 0 ); 621 break; 622 } 623 if( size&1 ){ 624 fprintf(out, "%p %6d bytes checked out\n", &mem3.aPool[i], (size/4)*8-8); 625 }else{ 626 fprintf(out, "%p %6d bytes free%s\n", &mem3.aPool[i], (size/4)*8-8, 627 i==mem3.iMaster ? " **master**" : ""); 628 } 629 } 630 for(i=0; i<MX_SMALL-1; i++){ 631 if( mem3.aiSmall[i]==0 ) continue; 632 fprintf(out, "small(%2d):", i); 633 for(j = mem3.aiSmall[i]; j>0; j=mem3.aPool[j].u.list.next){ 634 fprintf(out, " %p(%d)", &mem3.aPool[j], 635 (mem3.aPool[j-1].u.hdr.size4x/4)*8-8); 636 } 637 fprintf(out, "\n"); 638 } 639 for(i=0; i<N_HASH; i++){ 640 if( mem3.aiHash[i]==0 ) continue; 641 fprintf(out, "hash(%2d):", i); 642 for(j = mem3.aiHash[i]; j>0; j=mem3.aPool[j].u.list.next){ 643 fprintf(out, " %p(%d)", &mem3.aPool[j], 644 (mem3.aPool[j-1].u.hdr.size4x/4)*8-8); 645 } 646 fprintf(out, "\n"); 647 } 648 fprintf(out, "master=%d\n", mem3.iMaster); 649 fprintf(out, "nowUsed=%d\n", mem3.nPool*8 - mem3.szMaster*8); 650 fprintf(out, "mxUsed=%d\n", mem3.nPool*8 - mem3.mnMaster*8); 651 sqlite3_mutex_leave(mem3.mutex); 652 if( out==stdout ){ 653 fflush(stdout); 654 }else{ 655 fclose(out); 656 } 657#else 658 UNUSED_PARAMETER(zFilename); 659#endif 660} 661 662/* 663** This routine is the only routine in this file with external 664** linkage. 665** 666** Populate the low-level memory allocation function pointers in 667** sqlite3GlobalConfig.m with pointers to the routines in this file. The 668** arguments specify the block of memory to manage. 669** 670** This routine is only called by sqlite3_config(), and therefore 671** is not required to be threadsafe (it is not). 672*/ 673const sqlite3_mem_methods *sqlite3MemGetMemsys3(void){ 674 static const sqlite3_mem_methods mempoolMethods = { 675 memsys3Malloc, 676 memsys3Free, 677 memsys3Realloc, 678 memsys3Size, 679 memsys3Roundup, 680 memsys3Init, 681 memsys3Shutdown, 682 0 683 }; 684 return &mempoolMethods; 685} 686 687#endif /* SQLITE_ENABLE_MEMSYS3 */ 688