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Overview
Comment: | Add a debugging memory allocator. (CVS 4227) |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
8d2d1c4ff9dca61f75e3048107ee9712 |
User & Date: | drh 2007-08-15 17:07:57.000 |
Context
2007-08-15
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17:08 | Modify the crash-recovery test code in test6.c for 3.5. Also change some other code to use the new sqlite3_io_methods interface. Lots of things are broken now. (CVS 4228) (check-in: af9503daf3 user: danielk1977 tags: trunk) | |
17:07 | Add a debugging memory allocator. (CVS 4227) (check-in: 8d2d1c4ff9 user: drh tags: trunk) | |
13:04 | Add initial implementations of mutex and memory subsystem modules. (CVS 4226) (check-in: c0fa376979 user: drh tags: trunk) | |
Changes
Changes to main.mk.
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54 55 56 57 58 59 60 | TCCX = $(TCC) $(OPTS) $(THREADSAFE) $(USLEEP) -I. -I$(TOP)/src # Object files for the SQLite library. # LIBOBJ+= alter.o analyze.o attach.o auth.o btree.o build.o \ callback.o complete.o date.o delete.o \ expr.o func.o hash.o insert.o loadext.o \ | | | 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 | TCCX = $(TCC) $(OPTS) $(THREADSAFE) $(USLEEP) -I. -I$(TOP)/src # Object files for the SQLite library. # LIBOBJ+= alter.o analyze.o attach.o auth.o btree.o build.o \ callback.o complete.o date.o delete.o \ expr.o func.o hash.o insert.o loadext.o \ main.o malloc.o mem1.o mem2.o mutex.o \ opcodes.o os.o os_os2.o os_unix.o os_win.o \ pager.o parse.o pragma.o prepare.o printf.o random.o \ select.o table.o tclsqlite.o tokenize.o trigger.o \ update.o util.o vacuum.o \ vdbe.o vdbeapi.o vdbeaux.o vdbeblob.o vdbefifo.o vdbemem.o \ where.o utf.o legacy.o vtab.o |
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88 89 90 91 92 93 94 | $(TOP)/src/hash.c \ $(TOP)/src/hash.h \ $(TOP)/src/insert.c \ $(TOP)/src/legacy.c \ $(TOP)/src/loadext.c \ $(TOP)/src/main.c \ $(TOP)/src/malloc.c \ | | > | 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 | $(TOP)/src/hash.c \ $(TOP)/src/hash.h \ $(TOP)/src/insert.c \ $(TOP)/src/legacy.c \ $(TOP)/src/loadext.c \ $(TOP)/src/main.c \ $(TOP)/src/malloc.c \ $(TOP)/src/mem1.c \ $(TOP)/src/mem2.c \ $(TOP)/src/mutex.c \ $(TOP)/src/os.c \ $(TOP)/src/os_os2.c \ $(TOP)/src/os_unix.c \ $(TOP)/src/os_win.c \ $(TOP)/src/pager.c \ $(TOP)/src/pager.h \ |
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342 343 344 345 346 347 348 349 350 351 352 353 354 355 | $(TCCX) -c $(TOP)/src/main.c malloc.o: $(TOP)/src/malloc.c $(HDR) $(TCCX) -c $(TOP)/src/malloc.c mem1.o: $(TOP)/src/mem1.c $(HDR) $(TCCX) -c $(TOP)/src/mem1.c mutex.o: $(TOP)/src/mutex.c $(HDR) $(TCCX) -c $(TOP)/src/mutex.c pager.o: $(TOP)/src/pager.c $(HDR) $(TOP)/src/pager.h $(TCCX) -c $(TOP)/src/pager.c | > > > | 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 | $(TCCX) -c $(TOP)/src/main.c malloc.o: $(TOP)/src/malloc.c $(HDR) $(TCCX) -c $(TOP)/src/malloc.c mem1.o: $(TOP)/src/mem1.c $(HDR) $(TCCX) -c $(TOP)/src/mem1.c mem2.o: $(TOP)/src/mem2.c $(HDR) $(TCCX) -c $(TOP)/src/mem2.c mutex.o: $(TOP)/src/mutex.c $(HDR) $(TCCX) -c $(TOP)/src/mutex.c pager.o: $(TOP)/src/pager.c $(HDR) $(TOP)/src/pager.h $(TCCX) -c $(TOP)/src/pager.c |
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Changes to src/mem1.c.
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8 9 10 11 12 13 14 | ** May you find forgiveness for yourself and forgive others. ** May you share freely, never taking more than you give. ** ************************************************************************* ** This file contains the C functions that implement a memory ** allocation subsystem for use by SQLite. ** | | > > > > > > > | 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 | ** May you find forgiveness for yourself and forgive others. ** May you share freely, never taking more than you give. ** ************************************************************************* ** This file contains the C functions that implement a memory ** allocation subsystem for use by SQLite. ** ** $Id: mem1.c,v 1.2 2007/08/15 17:07:57 drh Exp $ */ /* ** This version of the memory allocator is the default. It is ** used when no other memory allocator is specified using compile-time ** macros. */ #if !defined(SQLITE_MEMDEBUG) && !defined(SQLITE_OMIT_MEMORY_ALLOCATION) /* ** We will eventually construct multiple memory allocation subsystems ** suitable for use in various contexts: ** ** * Normal multi-threaded builds ** * Normal single-threaded builds |
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198 199 200 201 202 203 204 | if( nowUsed>mxUsed ){ mxUsed = nowUsed; } } sqlite3_mutex_leave(memMutex); return (void*)p; } | > > | 205 206 207 208 209 210 211 212 213 | if( nowUsed>mxUsed ){ mxUsed = nowUsed; } } sqlite3_mutex_leave(memMutex); return (void*)p; } #endif /* !SQLITE_MEMDEBUG && !SQLITE_OMIT_MEMORY_ALLOCATION */ |
Added src/mem2.c.
> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 | /* ** 2007 August 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. ** ************************************************************************* ** This file contains the C functions that implement a memory ** allocation subsystem for use by SQLite. ** ** $Id: mem2.c,v 1.1 2007/08/15 17:07:57 drh Exp $ */ /* ** This version of the memory allocator is used only if the ** SQLITE_MEMDEBUG macro is defined and SQLITE_OMIT_MEMORY_ALLOCATION ** is not defined. */ #if defined(SQLITE_MEMDEBUG) && !defined(SQLITE_OMIT_MEMORY_ALLOCATION) /* ** We will eventually construct multiple memory allocation subsystems ** suitable for use in various contexts: ** ** * Normal multi-threaded builds ** * Normal single-threaded builds ** * Debugging builds ** ** This version is suitable for use in debugging builds. ** ** Features: ** ** * Every allocate has guards at both ends. ** * New allocations are initialized with randomness ** * Allocations are overwritten with randomness when freed ** * Optional logs of malloc activity generated ** * Summary of outstanding allocations with backtraces to the ** point of allocation. ** * The ability to simulate memory allocation failure */ #include "sqliteInt.h" #include <stdio.h> /* ** The backtrace functionality is only available with GLIBC */ #ifdef __GLIBC__ extern int backtrace(void**,int); extern void backtrace_symbols_fd(void*const*,int,int); #else # define backtrace(A,B) 0 # define backtrace_symbols_fd(A,B,C) #endif /* ** Mutex to control access to the memory allocation subsystem. */ static sqlite3_mutex *memMutex = 0; /* ** Current allocation and high-water mark. */ static sqlite3_uint64 nowUsed = 0; static sqlite3_uint64 mxUsed = 0; /* ** The alarm callback and its arguments. The memMutex lock will ** be held while the callback is running. Recursive calls into ** the memory subsystem are allowed, but no new callbacks will be ** issued. The alarmBusy variable is set to prevent recursive ** callbacks. */ static void (*alarmCallback)(void*, sqlite3_uint64, unsigned) = 0; static void *alarmArg = 0; static sqlite3_uint64 alarmThreshold = (((sqlite3_uint64)1)<<63); static int alarmBusy = 0; /* ** Return the amount of memory currently checked out. */ sqlite3_uint64 sqlite3_memory_used(void){ sqlite3_uint64 n; if( memMutex==0 ){ memMutex = sqlite3_mutex_alloc(1); } sqlite3_mutex_enter(memMutex, 1); n = nowUsed; sqlite3_mutex_leave(memMutex); return n; } /* ** Return the maximum amount of memory that has ever been ** checked out since either the beginning of this process ** or since the most recent reset. */ sqlite3_uint64 sqlite3_memory_highwater(int resetFlag){ sqlite3_uint64 n; if( memMutex==0 ){ memMutex = sqlite3_mutex_alloc(1); } sqlite3_mutex_enter(memMutex, 1); n = mxUsed; if( resetFlag ){ mxUsed = nowUsed; } sqlite3_mutex_leave(memMutex); return n; } /* ** Change the alarm callback */ int sqlite3_memory_alarm( void(*xCallback)(void *pArg, sqlite3_uint64 used, unsigned int N), void *pArg, sqlite3_uint64 iThreshold ){ if( memMutex==0 ){ memMutex = sqlite3_mutex_alloc(1); } sqlite3_mutex_enter(memMutex, 1); alarmCallback = xCallback; alarmArg = pArg; alarmThreshold = iThreshold; sqlite3_mutex_leave(memMutex); return SQLITE_OK; } /* ** Trigger the alarm */ static void sqlite3MemsysAlarm(unsigned nByte){ if( alarmCallback==0 || alarmBusy ) return; alarmBusy = 1; alarmCallback(alarmArg, nowUsed, nByte); alarmBusy = 0; } /* ** Each memory allocation looks like this: ** ** ---------------------------------------------------------------- ** | backtrace pointers | MemBlockHdr | allocation | EndGuard | ** ---------------------------------------------------------------- ** ** The application code sees only a pointer to the allocation. We have ** to back up from the allocation pointer to find the MemBlockHdr. The ** MemBlockHdr tells us the size of the allocation and the number of ** backtrace pointers. There is also a guard word at the end of the ** MemBlockHdr. */ struct MemBlockHdr { struct MemBlockHdr *pNext, *pPrev; /* Linked list of all unfreed memory */ unsigned int iSize; /* Size of this allocation */ unsigned short nBacktrace; /* Number of backtraces on this alloc */ unsigned short nBacktraceSlots; /* Available backtrace slots */ unsigned int iForeGuard; /* Guard word for sanity */ }; /* ** Guard words */ #define FOREGUARD 0x80F5E153 #define REARGUARD 0xE4676B53 /* ** Head and tail of a linked list of all outstanding allocations */ static struct MemBlockHdr *pFirst = 0; static struct MemBlockHdr *pLast = 0; /* ** The number of levels of backtrace to save in new allocations. */ static int backtraceLevels = 0; /* ** Given an allocation, find the MemBlockHdr for that allocation. ** ** This routine checks the guards at either end of the allocation and ** if they are incorrect it asserts. */ static struct MemBlockHdr *sqlite3MemsysGetHeader(void *pAllocation){ struct MemBlockHdr *p; unsigned int *pInt; p = (struct MemBlockHdr*)pAllocation; p--; assert( p->iForeGuard==FOREGUARD ); assert( (p->iSize & 3)==0 ); pInt = (unsigned int*)pAllocation; assert( pInt[p->iSize/sizeof(unsigned int)]==REARGUARD ); return p; } /* ** Allocate nByte of memory */ void *sqlite3_malloc(unsigned int nByte){ struct MemBlockHdr *pHdr; void **pBt; unsigned int *pInt; void *p; unsigned int totalSize; if( memMutex==0 ){ memMutex = sqlite3_mutex_alloc(1); } sqlite3_mutex_enter(memMutex, 1); if( nowUsed+nByte>=alarmThreshold ){ sqlite3MemsysAlarm(nByte); } nByte = (nByte+3)&~3; totalSize = nByte + sizeof(*pHdr) + sizeof(unsigned int) + backtraceLevels*sizeof(void*); p = malloc(totalSize); if( p==0 ){ sqlite3MemsysAlarm(nByte); p = malloc(totalSize); } if( p ){ pBt = p; pHdr = (struct MemBlockHdr*)&pBt[backtraceLevels]; pHdr->pNext = 0; pHdr->pPrev = pLast; if( pLast ){ pLast->pNext = pHdr; }else{ pFirst = pHdr; } pLast = pHdr; pHdr->iForeGuard = FOREGUARD; pHdr->nBacktraceSlots = backtraceLevels; if( backtraceLevels ){ pHdr->nBacktrace = backtrace(pBt, backtraceLevels); }else{ pHdr->nBacktrace = 0; } pHdr->iSize = nByte; pInt = (unsigned int *)&pHdr[1]; pInt[nByte/sizeof(unsigned int)] = REARGUARD; memset(pInt, 0x65, nByte); nowUsed += nByte; if( nowUsed>mxUsed ){ mxUsed = nowUsed; } p = (void*)pInt; } sqlite3_mutex_leave(memMutex); return p; } /* ** Free memory. */ void sqlite3_free(void *pPrior){ struct MemBlockHdr *pHdr; void **pBt; if( pPrior==0 ){ return; } assert( memMutex!=0 ); pHdr = sqlite3MemsysGetHeader(pPrior); pBt = (void**)pHdr; pBt -= pHdr->nBacktraceSlots; sqlite3_mutex_enter(memMutex, 1); nowUsed -= pHdr->iSize; if( pHdr->pPrev ){ assert( pHdr->pPrev->pNext==pHdr ); pHdr->pPrev->pNext = pHdr->pNext; }else{ assert( pFirst==pHdr ); pFirst = pHdr->pNext; } if( pHdr->pNext ){ assert( pHdr->pNext->pPrev==pHdr ); pHdr->pNext->pPrev = pHdr->pPrev; }else{ assert( pLast==pHdr ); pLast = pHdr->pPrev; } memset(pBt, 0x2b, sizeof(void*)*pHdr->nBacktrace + sizeof(*pHdr) + pHdr->iSize + sizeof(unsigned int)); free(pBt); sqlite3_mutex_leave(memMutex); } /* ** Change the size of an existing memory allocation. ** ** For this debugging implementation, we *always* make a copy of the ** allocation into a new place in memory. In this way, if the ** higher level code is using pointer to the old allocation, it is ** much more likely to break and we are much more liking to find ** the error. */ void *sqlite3_realloc(void *pPrior, unsigned int nByte){ struct MemBlockHdr *pOldHdr; void *pNew; unsigned nOld; if( pPrior==0 ){ return sqlite3_malloc(nByte); } if( nByte==0 ){ sqlite3_free(pPrior); return; } pOldHdr = sqlite3MemsysGetHeader(pPrior); pNew = sqlite3_malloc(nByte); if( pNew ){ memcpy(pNew, pPrior, nByte<pOldHdr->iSize ? nByte : pOldHdr->iSize); if( nByte>pOldHdr->iSize ){ memset(&((char*)pNew)[pOldHdr->iSize], 0x2b, nByte - pOldHdr->iSize); } sqlite3_free(pPrior); } return pNew; } /* ** Set the number of backtrace levels kept for each allocation. ** A value of zero turns of backtracing. The number is always rounded ** up to a multiple of 2. */ void sqlite3_memdebug_backtrace_depth(int depth){ if( depth<0 ){ depth = 0; } if( depth>20 ){ depth = 20; } depth = (depth+1)&~1; backtraceLevels = depth; } /* ** Open the file indicated and write a log of all unfreed memory ** allocations into that log. */ void sqlite3_memdebug_dump(const char *zFilename){ FILE *out; struct MemBlockHdr *pHdr; void **pBt; out = fopen(zFilename, "w"); if( out==0 ){ fprintf(stderr, "** Unable to output memory debug output log: %s **\n", zFilename); return; } for(pHdr=pFirst; pHdr; pHdr=pHdr->pNext){ fprintf(out, "**** %d bytes at %p ****\n", pHdr->iSize, &pHdr[1]); if( pHdr->nBacktrace ){ fflush(out); pBt = (void**)pHdr; pBt -= pHdr->nBacktraceSlots; backtrace_symbols_fd(pBt, pHdr->nBacktrace, fileno(out)); fprintf(out, "\n"); } } fclose(out); } #endif /* SQLITE_MEMDEBUG && !SQLITE_OMIT_MEMORY_ALLOCATION */ |