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Overview
Comment: | Avoid pointer aliasing in the allocSpace() routine in vdbeaux.c. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
d6ae27512229d95502c584b17bb2cbdb |
User & Date: | drh 2009-12-08 15:35:23.000 |
Context
2009-12-08
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19:05 | Add tests to improve coverage of fts3. Associated bugfixes. (check-in: f0eac4175a user: dan tags: trunk) | |
15:35 | Avoid pointer aliasing in the allocSpace() routine in vdbeaux.c. (check-in: d6ae275122 user: drh tags: trunk) | |
15:16 | Begin updating API documentation to use the new MD5-hash based automatic requirements numbering. Comment changes only. Many similar changes will follow. (check-in: 973c5c86ee user: drh tags: trunk) | |
Changes
Changes to src/vdbeaux.c.
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1250 1251 1252 1253 1254 1255 1256 | z[j] = 0; sqlite3IoTrace("SQL %s\n", z); } } #endif /* !SQLITE_OMIT_TRACE && SQLITE_ENABLE_IOTRACE */ /* | | | | > > | | > > | | | | | | | | | | < > | 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 | z[j] = 0; sqlite3IoTrace("SQL %s\n", z); } } #endif /* !SQLITE_OMIT_TRACE && SQLITE_ENABLE_IOTRACE */ /* ** Allocate space from a fixed size buffer and return a pointer to ** that space. If insufficient space is available, return NULL. ** ** The pBuf parameter is the initial value of a pointer which will ** receive the new memory. pBuf is normally NULL. If pBuf is not ** NULL, it means that memory space has already been allocated and that ** this routine should not allocate any new memory. When pBuf is not ** NULL simply return pBuf. Only allocate new memory space when pBuf ** is NULL. ** ** nByte is the number of bytes of space needed. ** ** *ppFrom point to available space and pEnd points to the end of the ** available space. ** ** *pnByte is a counter of the number of bytes of space that have failed ** to allocate. If there is insufficient space in *ppFrom to satisfy the ** request, then increment *pnByte by the amount of the request. */ static void *allocSpace( void *pBuf, /* Where return pointer will be stored */ int nByte, /* Number of bytes to allocate */ u8 **ppFrom, /* IN/OUT: Allocate from *ppFrom */ u8 *pEnd, /* Pointer to 1 byte past the end of *ppFrom buffer */ int *pnByte /* If allocation cannot be made, increment *pnByte */ ){ assert( EIGHT_BYTE_ALIGNMENT(*ppFrom) ); if( pBuf ) return pBuf; nByte = ROUND8(nByte); if( &(*ppFrom)[nByte] <= pEnd ){ pBuf = (void*)*ppFrom; *ppFrom += nByte; }else{ *pnByte += nByte; } return pBuf; } /* ** Prepare a virtual machine for execution. This involves things such ** as allocating stack space and initializing the program counter. ** After the VDBE has be prepped, it can be executed by one or more ** calls to sqlite3VdbeExec(). |
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1354 1355 1356 1357 1358 1359 1360 | } memset(zCsr, 0, zEnd-zCsr); zCsr += (zCsr - (u8*)0)&7; assert( EIGHT_BYTE_ALIGNMENT(zCsr) ); do { nByte = 0; | | | | | | | < | 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 | } memset(zCsr, 0, zEnd-zCsr); zCsr += (zCsr - (u8*)0)&7; assert( EIGHT_BYTE_ALIGNMENT(zCsr) ); do { nByte = 0; p->aMem = allocSpace(p->aMem, nMem*sizeof(Mem), &zCsr, zEnd, &nByte); p->aVar = allocSpace(p->aVar, nVar*sizeof(Mem), &zCsr, zEnd, &nByte); p->apArg = allocSpace(p->apArg, nArg*sizeof(Mem*), &zCsr, zEnd, &nByte); p->azVar = allocSpace(p->azVar, nVar*sizeof(char*), &zCsr, zEnd, &nByte); p->apCsr = allocSpace(p->apCsr, nCursor*sizeof(VdbeCursor*), &zCsr, zEnd, &nByte); if( nByte ){ p->pFree = sqlite3DbMallocZero(db, nByte); } zCsr = p->pFree; zEnd = &zCsr[nByte]; }while( nByte && !db->mallocFailed ); |
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