AryaWu/sqlite
0
1/*2** 2008 Jan 223**4** The author disclaims copyright to this source code. In place of5** 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** This file contains code that modified the OS layer in order to simulate14** different device types (by overriding the return values of the 15** xDeviceCharacteristics() and xSectorSize() methods).16*/17#if SQLITE_TEST /* This file is used for testing only */18 19#include "sqlite3.h"20#include "sqliteInt.h"21 22/*23** Maximum pathname length supported by the devsym backend.24*/25#define DEVSYM_MAX_PATHNAME 51226 27/*28** Name used to identify this VFS.29*/30#define DEVSYM_VFS_NAME "devsym"31#define WRITECRASH_NAME "writecrash"32 33typedef struct devsym_file devsym_file;34struct devsym_file {35 sqlite3_file base;36 sqlite3_file *pReal;37};38 39/*40** Method declarations for devsym_file.41*/42static int devsymClose(sqlite3_file*);43static int devsymRead(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);44static int devsymWrite(sqlite3_file*,const void*,int iAmt, sqlite3_int64 iOfst);45static int devsymTruncate(sqlite3_file*, sqlite3_int64 size);46static int devsymSync(sqlite3_file*, int flags);47static int devsymFileSize(sqlite3_file*, sqlite3_int64 *pSize);48static int devsymLock(sqlite3_file*, int);49static int devsymUnlock(sqlite3_file*, int);50static int devsymCheckReservedLock(sqlite3_file*, int *);51static int devsymFileControl(sqlite3_file*, int op, void *pArg);52static int devsymSectorSize(sqlite3_file*);53static int devsymDeviceCharacteristics(sqlite3_file*);54static int devsymShmLock(sqlite3_file*,int,int,int);55static int devsymShmMap(sqlite3_file*,int,int,int, void volatile **);56static void devsymShmBarrier(sqlite3_file*);57static int devsymShmUnmap(sqlite3_file*,int);58 59/*60** Method declarations for devsym_vfs.61*/62static int devsymOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *);63static int devsymDelete(sqlite3_vfs*, const char *zName, int syncDir);64static int devsymAccess(sqlite3_vfs*, const char *zName, int flags, int *);65static int devsymFullPathname(sqlite3_vfs*, const char *zName, int, char *zOut);66#ifndef SQLITE_OMIT_LOAD_EXTENSION67static void *devsymDlOpen(sqlite3_vfs*, const char *zFilename);68static void devsymDlError(sqlite3_vfs*, int nByte, char *zErrMsg);69static void (*devsymDlSym(sqlite3_vfs*,void*, const char *zSymbol))(void);70static void devsymDlClose(sqlite3_vfs*, void*);71#endif /* SQLITE_OMIT_LOAD_EXTENSION */72static int devsymRandomness(sqlite3_vfs*, int nByte, char *zOut);73static int devsymSleep(sqlite3_vfs*, int microseconds);74static int devsymCurrentTime(sqlite3_vfs*, double*);75 76struct DevsymGlobal {77 sqlite3_vfs *pVfs;78 int iDeviceChar;79 int iSectorSize;80 int nWriteCrash;81};82struct DevsymGlobal g = {0, 0, 512, 0};83 84/*85** Close an devsym-file.86*/87static int devsymClose(sqlite3_file *pFile){88 devsym_file *p = (devsym_file *)pFile;89 sqlite3OsClose(p->pReal);90 return SQLITE_OK;91}92 93/*94** Read data from an devsym-file.95*/96static int devsymRead(97 sqlite3_file *pFile, 98 void *zBuf, 99 int iAmt, 100 sqlite_int64 iOfst101){102 devsym_file *p = (devsym_file *)pFile;103 return sqlite3OsRead(p->pReal, zBuf, iAmt, iOfst);104}105 106/*107** Write data to an devsym-file.108*/109static int devsymWrite(110 sqlite3_file *pFile, 111 const void *zBuf, 112 int iAmt, 113 sqlite_int64 iOfst114){115 devsym_file *p = (devsym_file *)pFile;116 return sqlite3OsWrite(p->pReal, zBuf, iAmt, iOfst);117}118 119/*120** Truncate an devsym-file.121*/122static int devsymTruncate(sqlite3_file *pFile, sqlite_int64 size){123 devsym_file *p = (devsym_file *)pFile;124 return sqlite3OsTruncate(p->pReal, size);125}126 127/*128** Sync an devsym-file.129*/130static int devsymSync(sqlite3_file *pFile, int flags){131 devsym_file *p = (devsym_file *)pFile;132 return sqlite3OsSync(p->pReal, flags);133}134 135/*136** Return the current file-size of an devsym-file.137*/138static int devsymFileSize(sqlite3_file *pFile, sqlite_int64 *pSize){139 devsym_file *p = (devsym_file *)pFile;140 return sqlite3OsFileSize(p->pReal, pSize);141}142 143/*144** Lock an devsym-file.145*/146static int devsymLock(sqlite3_file *pFile, int eLock){147 devsym_file *p = (devsym_file *)pFile;148 return sqlite3OsLock(p->pReal, eLock);149}150 151/*152** Unlock an devsym-file.153*/154static int devsymUnlock(sqlite3_file *pFile, int eLock){155 devsym_file *p = (devsym_file *)pFile;156 return sqlite3OsUnlock(p->pReal, eLock);157}158 159/*160** Check if another file-handle holds a RESERVED lock on an devsym-file.161*/162static int devsymCheckReservedLock(sqlite3_file *pFile, int *pResOut){163 devsym_file *p = (devsym_file *)pFile;164 return sqlite3OsCheckReservedLock(p->pReal, pResOut);165}166 167/*168** File control method. For custom operations on an devsym-file.169*/170static int devsymFileControl(sqlite3_file *pFile, int op, void *pArg){171 devsym_file *p = (devsym_file *)pFile;172 return sqlite3OsFileControl(p->pReal, op, pArg);173}174 175/*176** Return the sector-size in bytes for an devsym-file.177*/178static int devsymSectorSize(sqlite3_file *pFile){179 return g.iSectorSize;180}181 182/*183** Return the device characteristic flags supported by an devsym-file.184*/185static int devsymDeviceCharacteristics(sqlite3_file *pFile){186 return g.iDeviceChar;187}188 189/*190** Shared-memory methods are all pass-throughs.191*/192static int devsymShmLock(sqlite3_file *pFile, int ofst, int n, int flags){193 devsym_file *p = (devsym_file *)pFile;194 return p->pReal->pMethods->xShmLock(p->pReal, ofst, n, flags);195}196static int devsymShmMap(197 sqlite3_file *pFile, 198 int iRegion, 199 int szRegion, 200 int isWrite, 201 void volatile **pp202){203 devsym_file *p = (devsym_file *)pFile;204 return p->pReal->pMethods->xShmMap(p->pReal, iRegion, szRegion, isWrite, pp);205}206static void devsymShmBarrier(sqlite3_file *pFile){207 devsym_file *p = (devsym_file *)pFile;208 p->pReal->pMethods->xShmBarrier(p->pReal);209}210static int devsymShmUnmap(sqlite3_file *pFile, int delFlag){211 devsym_file *p = (devsym_file *)pFile;212 return p->pReal->pMethods->xShmUnmap(p->pReal, delFlag);213}214 215 216 217/*218** Open an devsym file handle.219*/220static int devsymOpen(221 sqlite3_vfs *pVfs,222 const char *zName,223 sqlite3_file *pFile,224 int flags,225 int *pOutFlags226){227static sqlite3_io_methods devsym_io_methods = {228 2, /* iVersion */229 devsymClose, /* xClose */230 devsymRead, /* xRead */231 devsymWrite, /* xWrite */232 devsymTruncate, /* xTruncate */233 devsymSync, /* xSync */234 devsymFileSize, /* xFileSize */235 devsymLock, /* xLock */236 devsymUnlock, /* xUnlock */237 devsymCheckReservedLock, /* xCheckReservedLock */238 devsymFileControl, /* xFileControl */239 devsymSectorSize, /* xSectorSize */240 devsymDeviceCharacteristics, /* xDeviceCharacteristics */241 devsymShmMap, /* xShmMap */242 devsymShmLock, /* xShmLock */243 devsymShmBarrier, /* xShmBarrier */244 devsymShmUnmap /* xShmUnmap */245};246 247 int rc;248 devsym_file *p = (devsym_file *)pFile;249 p->pReal = (sqlite3_file *)&p[1];250 rc = sqlite3OsOpen(g.pVfs, zName, p->pReal, flags, pOutFlags);251 if( p->pReal->pMethods ){252 pFile->pMethods = &devsym_io_methods;253 }254 return rc;255}256 257/*258** Delete the file located at zPath. If the dirSync argument is true,259** ensure the file-system modifications are synced to disk before260** returning.261*/262static int devsymDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){263 return sqlite3OsDelete(g.pVfs, zPath, dirSync);264}265 266/*267** Test for access permissions. Return true if the requested permission268** is available, or false otherwise.269*/270static int devsymAccess(271 sqlite3_vfs *pVfs, 272 const char *zPath, 273 int flags, 274 int *pResOut275){276 return sqlite3OsAccess(g.pVfs, zPath, flags, pResOut);277}278 279/*280** Populate buffer zOut with the full canonical pathname corresponding281** to the pathname in zPath. zOut is guaranteed to point to a buffer282** of at least (DEVSYM_MAX_PATHNAME+1) bytes.283*/284static int devsymFullPathname(285 sqlite3_vfs *pVfs, 286 const char *zPath, 287 int nOut, 288 char *zOut289){290 return sqlite3OsFullPathname(g.pVfs, zPath, nOut, zOut);291}292 293#ifndef SQLITE_OMIT_LOAD_EXTENSION294/*295** Open the dynamic library located at zPath and return a handle.296*/297static void *devsymDlOpen(sqlite3_vfs *pVfs, const char *zPath){298 return sqlite3OsDlOpen(g.pVfs, zPath);299}300 301/*302** Populate the buffer zErrMsg (size nByte bytes) with a human readable303** utf-8 string describing the most recent error encountered associated 304** with dynamic libraries.305*/306static void devsymDlError(sqlite3_vfs *pVfs, int nByte, char *zErrMsg){307 sqlite3OsDlError(g.pVfs, nByte, zErrMsg);308}309 310/*311** Return a pointer to the symbol zSymbol in the dynamic library pHandle.312*/313static void (*devsymDlSym(sqlite3_vfs *pVfs, void *p, const char *zSym))(void){314 return sqlite3OsDlSym(g.pVfs, p, zSym);315}316 317/*318** Close the dynamic library handle pHandle.319*/320static void devsymDlClose(sqlite3_vfs *pVfs, void *pHandle){321 sqlite3OsDlClose(g.pVfs, pHandle);322}323#endif /* SQLITE_OMIT_LOAD_EXTENSION */324 325/*326** Populate the buffer pointed to by zBufOut with nByte bytes of 327** random data.328*/329static int devsymRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){330 return sqlite3OsRandomness(g.pVfs, nByte, zBufOut);331}332 333/*334** Sleep for nMicro microseconds. Return the number of microseconds 335** actually slept.336*/337static int devsymSleep(sqlite3_vfs *pVfs, int nMicro){338 return sqlite3OsSleep(g.pVfs, nMicro);339}340 341/*342** Return the current time as a Julian Day number in *pTimeOut.343*/344static int devsymCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){345 return g.pVfs->xCurrentTime(g.pVfs, pTimeOut);346}347 348/*349** Return the sector-size in bytes for an writecrash-file.350*/351static int writecrashSectorSize(sqlite3_file *pFile){352 devsym_file *p = (devsym_file *)pFile;353 return sqlite3OsSectorSize(p->pReal);354}355 356/*357** Return the device characteristic flags supported by an writecrash-file.358*/359static int writecrashDeviceCharacteristics(sqlite3_file *pFile){360 devsym_file *p = (devsym_file *)pFile;361 return sqlite3OsDeviceCharacteristics(p->pReal);362}363 364/*365** Write data to an writecrash-file.366*/367static int writecrashWrite(368 sqlite3_file *pFile, 369 const void *zBuf, 370 int iAmt, 371 sqlite_int64 iOfst372){373 devsym_file *p = (devsym_file *)pFile;374 if( g.nWriteCrash>0 ){375 g.nWriteCrash--;376 if( g.nWriteCrash==0 ) abort();377 }378 return sqlite3OsWrite(p->pReal, zBuf, iAmt, iOfst);379}380 381/*382** Open an writecrash file handle.383*/384static int writecrashOpen(385 sqlite3_vfs *pVfs,386 const char *zName,387 sqlite3_file *pFile,388 int flags,389 int *pOutFlags390){391static sqlite3_io_methods writecrash_io_methods = {392 2, /* iVersion */393 devsymClose, /* xClose */394 devsymRead, /* xRead */395 writecrashWrite, /* xWrite */396 devsymTruncate, /* xTruncate */397 devsymSync, /* xSync */398 devsymFileSize, /* xFileSize */399 devsymLock, /* xLock */400 devsymUnlock, /* xUnlock */401 devsymCheckReservedLock, /* xCheckReservedLock */402 devsymFileControl, /* xFileControl */403 writecrashSectorSize, /* xSectorSize */404 writecrashDeviceCharacteristics, /* xDeviceCharacteristics */405 devsymShmMap, /* xShmMap */406 devsymShmLock, /* xShmLock */407 devsymShmBarrier, /* xShmBarrier */408 devsymShmUnmap /* xShmUnmap */409};410 411 int rc;412 devsym_file *p = (devsym_file *)pFile;413 p->pReal = (sqlite3_file *)&p[1];414 rc = sqlite3OsOpen(g.pVfs, zName, p->pReal, flags, pOutFlags);415 if( p->pReal->pMethods ){416 pFile->pMethods = &writecrash_io_methods;417 }418 return rc;419}420 421static sqlite3_vfs devsym_vfs = {422 2, /* iVersion */423 sizeof(devsym_file), /* szOsFile */424 DEVSYM_MAX_PATHNAME, /* mxPathname */425 0, /* pNext */426 DEVSYM_VFS_NAME, /* zName */427 0, /* pAppData */428 devsymOpen, /* xOpen */429 devsymDelete, /* xDelete */430 devsymAccess, /* xAccess */431 devsymFullPathname, /* xFullPathname */432#ifndef SQLITE_OMIT_LOAD_EXTENSION433 devsymDlOpen, /* xDlOpen */434 devsymDlError, /* xDlError */435 devsymDlSym, /* xDlSym */436 devsymDlClose, /* xDlClose */437#else438 0, /* xDlOpen */439 0, /* xDlError */440 0, /* xDlSym */441 0, /* xDlClose */442#endif /* SQLITE_OMIT_LOAD_EXTENSION */443 devsymRandomness, /* xRandomness */444 devsymSleep, /* xSleep */445 devsymCurrentTime, /* xCurrentTime */446 0, /* xGetLastError */447 0 /* xCurrentTimeInt64 */448};449 450static sqlite3_vfs writecrash_vfs = {451 2, /* iVersion */452 sizeof(devsym_file), /* szOsFile */453 DEVSYM_MAX_PATHNAME, /* mxPathname */454 0, /* pNext */455 WRITECRASH_NAME, /* zName */456 0, /* pAppData */457 writecrashOpen, /* xOpen */458 devsymDelete, /* xDelete */459 devsymAccess, /* xAccess */460 devsymFullPathname, /* xFullPathname */461#ifndef SQLITE_OMIT_LOAD_EXTENSION462 devsymDlOpen, /* xDlOpen */463 devsymDlError, /* xDlError */464 devsymDlSym, /* xDlSym */465 devsymDlClose, /* xDlClose */466#else467 0, /* xDlOpen */468 0, /* xDlError */469 0, /* xDlSym */470 0, /* xDlClose */471#endif /* SQLITE_OMIT_LOAD_EXTENSION */472 devsymRandomness, /* xRandomness */473 devsymSleep, /* xSleep */474 devsymCurrentTime, /* xCurrentTime */475 0, /* xGetLastError */476 0 /* xCurrentTimeInt64 */477};478 479 480/*481** This procedure registers the devsym vfs with SQLite. If the argument is482** true, the devsym vfs becomes the new default vfs. It is the only publicly483** available function in this file.484*/485void devsym_register(int iDeviceChar, int iSectorSize){486 487 if( g.pVfs==0 ){488 g.pVfs = sqlite3_vfs_find(0);489 devsym_vfs.szOsFile += g.pVfs->szOsFile;490 writecrash_vfs.szOsFile += g.pVfs->szOsFile;491 sqlite3_vfs_register(&devsym_vfs, 0);492 sqlite3_vfs_register(&writecrash_vfs, 0);493 }494 if( iDeviceChar>=0 ){495 g.iDeviceChar = iDeviceChar;496 }else{497 g.iDeviceChar = 0;498 }499 if( iSectorSize>=0 ){500 g.iSectorSize = iSectorSize;501 }else{502 g.iSectorSize = 512;503 }504}505 506void devsym_unregister(){507 sqlite3_vfs_unregister(&devsym_vfs);508 sqlite3_vfs_unregister(&writecrash_vfs);509 g.pVfs = 0;510 g.iDeviceChar = 0;511 g.iSectorSize = 0;512}513 514void devsym_crash_on_write(int nWrite){515 if( g.pVfs==0 ){516 g.pVfs = sqlite3_vfs_find(0);517 devsym_vfs.szOsFile += g.pVfs->szOsFile;518 writecrash_vfs.szOsFile += g.pVfs->szOsFile;519 sqlite3_vfs_register(&devsym_vfs, 0);520 sqlite3_vfs_register(&writecrash_vfs, 0);521 }522 g.nWriteCrash = nWrite;523}524 525#endif526