/* ** Make sure all writes to a particular file are committed to disk. ** ** Under Unix, also make sure that the directory entry for the file ** has been created by fsync-ing the directory that contains the file. ** If we do not do this and we encounter a power failure, the directory ** entry for the journal might not exist after we reboot. The next ** SQLite to access the file will not know that the journal exists (because ** the directory entry for the journal was never created) and the transaction ** will not roll back - possibly leading to database corruption. */ int sqlite3OsSync(OsFile *id){ assert( id->isOpen ); SimulateIOError(SQLITE_IOERR); TRACE2("SYNC %-3d\n", id->h); if( full_fsync(id->h, id->fullSync) ){ return SQLITE_IOERR; } if( id->dirfd>=0 ){ TRACE2("DIRSYNC %-3d\n", id->dirfd); full_fsync(id->dirfd, id->fullSync); close(id->dirfd); /* Only need to sync once, so close the directory */ id->dirfd = -1; /* when we are done. */ } return SQLITE_OK; }
/* ** Make sure all writes to a particular file are committed to disk. ** ** If dataOnly==0 then both the file itself and its metadata (file ** size, access time, etc) are synced. If dataOnly!=0 then only the ** file data is synced. ** ** Under Unix, also make sure that the directory entry for the file ** has been created by fsync-ing the directory that contains the file. ** If we do not do this and we encounter a power failure, the directory ** entry for the journal might not exist after we reboot. The next ** SQLite to access the file will not know that the journal exists (because ** the directory entry for the journal was never created) and the transaction ** will not roll back - possibly leading to database corruption. */ static int unixSync(sqlite3_file *id, int flags){ int rc; unixFile *pFile = (unixFile*)id; int isDataOnly = (flags&SQLITE_SYNC_DATAONLY); int isFullsync = (flags&0x0F)==SQLITE_SYNC_FULL; /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */ assert((flags&0x0F)==SQLITE_SYNC_NORMAL || (flags&0x0F)==SQLITE_SYNC_FULL ); /* Unix cannot, but some systems may return SQLITE_FULL from here. This ** line is to test that doing so does not cause any problems. */ SimulateDiskfullError( return SQLITE_FULL ); assert( pFile ); OSTRACE2("SYNC %-3d\n", pFile->h); rc = full_fsync(pFile->h, isFullsync, isDataOnly); SimulateIOError( rc=1 ); if( rc ){ return SQLITE_IOERR_FSYNC; } return SQLITE_OK; }