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Changes In Branch snapshot-get Excluding Merge-Ins
This is equivalent to a diff from 901d0b8f to 843c15a5
2015-12-11
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12:44 | Add the experimental snapshot interface. Because it is experimental, it is subject to change or removal at a later date. (check-in: 9b124a5a user: drh tags: trunk) | |
03:27 | Mention that the snapshot interfaces are only available if SQLite is compiled with SQLITE_ENABLE_SNAPSHOT. (Closed-Leaf check-in: 843c15a5 user: drh tags: snapshot-get) | |
03:20 | Disable the snapshot test scripts if not compiled with SQLITE_ENABLE_SNAPSHOT. (check-in: 5fd008f0 user: drh tags: snapshot-get) | |
2015-12-09
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16:26 | Simplification of the DROP TRIGGER logic using sqlite3NestedParse() instead of hand-coded VDBE code. This is a manual cherry-pick of the key change from check-in [c80bbf14b365d]. (check-in: 8021b4c8 user: drh tags: trunk) | |
16:04 | Merge unrelated fixes from trunk. (check-in: 362615b4 user: drh tags: snapshot-get) | |
08:13 | Merge latest trunk with this branch. (check-in: dc236f11 user: dan tags: onepass-delete-or) | |
2015-12-08
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16:58 | Changes to avoid undefined behavior in memset() and memcpy() and in the comparisons of pointers from different allocations. All problems are found by analysis tools - none have been seen in the wild. (check-in: 901d0b8f user: drh tags: trunk) | |
16:08 | Avoid doing comparisons with pointers that might have been previously been passed to realloc() and/or free(). (check-in: f20396ad user: drh tags: trunk) | |
Changes to src/main.c.
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3862 3863 3864 3865 3866 3867 3868 | (void)SQLITE_MISUSE_BKPT; return -1; } #endif pBt = sqlite3DbNameToBtree(db, zDbName); return pBt ? sqlite3BtreeIsReadonly(pBt) : -1; } | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 3862 3863 3864 3865 3866 3867 3868 3869 3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931 3932 3933 3934 3935 3936 3937 3938 3939 3940 3941 3942 3943 3944 3945 3946 3947 3948 3949 3950 3951 | (void)SQLITE_MISUSE_BKPT; return -1; } #endif pBt = sqlite3DbNameToBtree(db, zDbName); return pBt ? sqlite3BtreeIsReadonly(pBt) : -1; } #ifdef SQLITE_ENABLE_SNAPSHOT /* ** Obtain a snapshot handle for the snapshot of database zDb currently ** being read by handle db. */ int sqlite3_snapshot_get( sqlite3 *db, const char *zDb, sqlite3_snapshot **ppSnapshot ){ int rc = SQLITE_ERROR; #ifndef SQLITE_OMIT_WAL int iDb; #ifdef SQLITE_ENABLE_API_ARMOR if( !sqlite3SafetyCheckOk(db) ){ return SQLITE_MISUSE_BKPT; } #endif sqlite3_mutex_enter(db->mutex); iDb = sqlite3FindDbName(db, zDb); if( iDb==0 || iDb>1 ){ Btree *pBt = db->aDb[iDb].pBt; if( 0==sqlite3BtreeIsInTrans(pBt) ){ rc = sqlite3BtreeBeginTrans(pBt, 0); if( rc==SQLITE_OK ){ rc = sqlite3PagerSnapshotGet(sqlite3BtreePager(pBt), ppSnapshot); } } } sqlite3_mutex_leave(db->mutex); #endif /* SQLITE_OMIT_WAL */ return rc; } /* ** Open a read-transaction on the snapshot idendified by pSnapshot. */ int sqlite3_snapshot_open( sqlite3 *db, const char *zDb, sqlite3_snapshot *pSnapshot ){ int rc = SQLITE_ERROR; #ifndef SQLITE_OMIT_WAL #ifdef SQLITE_ENABLE_API_ARMOR if( !sqlite3SafetyCheckOk(db) ){ return SQLITE_MISUSE_BKPT; } #endif sqlite3_mutex_enter(db->mutex); if( db->autoCommit==0 ){ int iDb; iDb = sqlite3FindDbName(db, zDb); if( iDb==0 || iDb>1 ){ Btree *pBt = db->aDb[iDb].pBt; if( 0==sqlite3BtreeIsInReadTrans(pBt) ){ rc = sqlite3PagerSnapshotOpen(sqlite3BtreePager(pBt), pSnapshot); if( rc==SQLITE_OK ){ rc = sqlite3BtreeBeginTrans(pBt, 0); sqlite3PagerSnapshotOpen(sqlite3BtreePager(pBt), 0); } } } } sqlite3_mutex_leave(db->mutex); #endif /* SQLITE_OMIT_WAL */ return rc; } /* ** Free a snapshot handle obtained from sqlite3_snapshot_get(). */ void sqlite3_snapshot_free(sqlite3_snapshot *pSnapshot){ sqlite3_free(pSnapshot); } #endif /* SQLITE_ENABLE_SNAPSHOT */ |
Changes to src/pager.c.
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7297 7298 7299 7300 7301 7302 7303 7304 7305 7306 7307 7308 7309 7310 | pPager->pWal = 0; pagerFixMaplimit(pPager); } } return rc; } #endif /* !SQLITE_OMIT_WAL */ #ifdef SQLITE_ENABLE_ZIPVFS /* ** A read-lock must be held on the pager when this function is called. If ** the pager is in WAL mode and the WAL file currently contains one or more ** frames, return the size in bytes of the page images stored within the | > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 7297 7298 7299 7300 7301 7302 7303 7304 7305 7306 7307 7308 7309 7310 7311 7312 7313 7314 7315 7316 7317 7318 7319 7320 7321 7322 7323 7324 7325 7326 7327 7328 7329 7330 7331 7332 7333 7334 7335 7336 7337 7338 | pPager->pWal = 0; pagerFixMaplimit(pPager); } } return rc; } #ifdef SQLITE_ENABLE_SNAPSHOT /* ** If this is a WAL database, obtain a snapshot handle for the snapshot ** currently open. Otherwise, return an error. */ int sqlite3PagerSnapshotGet(Pager *pPager, sqlite3_snapshot **ppSnapshot){ int rc = SQLITE_ERROR; if( pPager->pWal ){ rc = sqlite3WalSnapshotGet(pPager->pWal, ppSnapshot); } return rc; } /* ** If this is a WAL database, store a pointer to pSnapshot. Next time a ** read transaction is opened, attempt to read from the snapshot it ** identifies. If this is not a WAL database, return an error. */ int sqlite3PagerSnapshotOpen(Pager *pPager, sqlite3_snapshot *pSnapshot){ int rc = SQLITE_OK; if( pPager->pWal ){ sqlite3WalSnapshotOpen(pPager->pWal, pSnapshot); }else{ rc = SQLITE_ERROR; } return rc; } #endif /* SQLITE_ENABLE_SNAPSHOT */ #endif /* !SQLITE_OMIT_WAL */ #ifdef SQLITE_ENABLE_ZIPVFS /* ** A read-lock must be held on the pager when this function is called. If ** the pager is in WAL mode and the WAL file currently contains one or more ** frames, return the size in bytes of the page images stored within the |
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Changes to src/pager.h.
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164 165 166 167 168 169 170 171 172 173 174 175 176 177 | #ifndef SQLITE_OMIT_WAL int sqlite3PagerCheckpoint(Pager *pPager, int, int*, int*); int sqlite3PagerWalSupported(Pager *pPager); int sqlite3PagerWalCallback(Pager *pPager); int sqlite3PagerOpenWal(Pager *pPager, int *pisOpen); int sqlite3PagerCloseWal(Pager *pPager); #endif #ifdef SQLITE_ENABLE_ZIPVFS int sqlite3PagerWalFramesize(Pager *pPager); #endif /* Functions used to query pager state and configuration. */ | > > > > | 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 | #ifndef SQLITE_OMIT_WAL int sqlite3PagerCheckpoint(Pager *pPager, int, int*, int*); int sqlite3PagerWalSupported(Pager *pPager); int sqlite3PagerWalCallback(Pager *pPager); int sqlite3PagerOpenWal(Pager *pPager, int *pisOpen); int sqlite3PagerCloseWal(Pager *pPager); # ifdef SQLITE_ENABLE_SNAPSHOT int sqlite3PagerSnapshotGet(Pager *pPager, sqlite3_snapshot **ppSnapshot); int sqlite3PagerSnapshotOpen(Pager *pPager, sqlite3_snapshot *pSnapshot); # endif #endif #ifdef SQLITE_ENABLE_ZIPVFS int sqlite3PagerWalFramesize(Pager *pPager); #endif /* Functions used to query pager state and configuration. */ |
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Changes to src/sqlite.h.in.
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4401 4402 4403 4404 4405 4406 4407 | ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a ** memory allocation fails. ** ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer ** then sqlite3_value_free(V) is a harmless no-op. */ | | | | 4401 4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 | ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a ** memory allocation fails. ** ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer ** then sqlite3_value_free(V) is a harmless no-op. */ sqlite3_value *sqlite3_value_dup(const sqlite3_value*); void sqlite3_value_free(sqlite3_value*); /* ** CAPI3REF: Obtain Aggregate Function Context ** METHOD: sqlite3_context ** ** Implementations of aggregate SQL functions use this ** routine to allocate memory for storing their state. |
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7847 7848 7849 7850 7851 7852 7853 | ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. */ void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); /* ** CAPI3REF: Flush caches to disk mid-transaction ** | | > | | > | | | | | | | | | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 7847 7848 7849 7850 7851 7852 7853 7854 7855 7856 7857 7858 7859 7860 7861 7862 7863 7864 7865 7866 7867 7868 7869 7870 7871 7872 7873 7874 7875 7876 7877 7878 7879 7880 7881 7882 7883 7884 7885 7886 7887 7888 7889 7890 7891 7892 7893 7894 7895 7896 7897 7898 7899 7900 7901 7902 7903 7904 7905 7906 7907 7908 7909 7910 7911 7912 7913 7914 7915 7916 7917 7918 7919 7920 7921 7922 7923 7924 7925 7926 7927 7928 7929 7930 7931 7932 7933 7934 7935 7936 7937 7938 7939 7940 7941 7942 7943 7944 7945 7946 7947 7948 7949 7950 7951 7952 7953 7954 7955 7956 7957 7958 7959 7960 7961 7962 7963 7964 7965 7966 7967 7968 7969 7970 7971 7972 7973 7974 7975 7976 7977 7978 7979 7980 7981 7982 7983 7984 7985 7986 | ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. */ void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); /* ** CAPI3REF: Flush caches to disk mid-transaction ** ** ^If a write-transaction is open on [database connection] D when the ** [sqlite3_db_cacheflush(D)] interface invoked, any dirty ** pages in the pager-cache that are not currently in use are written out ** to disk. A dirty page may be in use if a database cursor created by an ** active SQL statement is reading from it, or if it is page 1 of a database ** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] ** interface flushes caches for all schemas - "main", "temp", and ** any [attached] databases. ** ** ^If this function needs to obtain extra database locks before dirty pages ** can be flushed to disk, it does so. ^If those locks cannot be obtained ** immediately and there is a busy-handler callback configured, it is invoked ** in the usual manner. ^If the required lock still cannot be obtained, then ** the database is skipped and an attempt made to flush any dirty pages ** belonging to the next (if any) database. ^If any databases are skipped ** because locks cannot be obtained, but no other error occurs, this ** function returns SQLITE_BUSY. ** ** ^If any other error occurs while flushing dirty pages to disk (for ** example an IO error or out-of-memory condition), then processing is ** abandoned and an SQLite [error code] is returned to the caller immediately. ** ** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. ** ** ^This function does not set the database handle error code or message ** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. */ int sqlite3_db_cacheflush(sqlite3*); /* ** CAPI3REF: Database Snapshot ** KEYWORDS: {snapshot} ** EXPERIMENTAL ** ** An instance of the snapshot object records the state of a [WAL mode] ** database for some specific point in history. ** ** In [WAL mode], multiple [database connections] that are open on the ** same database file can each be reading a different historical version ** of the database file. When a [database connection] begins a read ** transaction, that connection sees an unchanging copy of the database ** as it existed for the point in time when the transaction first started. ** Subsequent changes to the database from other connections are not seen ** by the reader until a new read transaction is started. ** ** The sqlite3_snapshot object records state information about an historical ** version of the database file so that it is possible to later open a new read ** transaction that sees that historical version of the database rather than ** the most recent version. ** ** The constructor for this object is [sqlite3_snapshot_get()]. The ** [sqlite3_snapshot_open()] method causes a fresh read transaction to refer ** to an historical snapshot (if possible). The destructor for ** sqlite3_snapshot objects is [sqlite3_snapshot_free()]. */ typedef struct sqlite3_snapshot sqlite3_snapshot; /* ** CAPI3REF: Record A Database Snapshot ** EXPERIMENTAL ** ** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a ** new [sqlite3_snapshot] object that records the current state of ** schema S in database connection D. ^On success, the ** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly ** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. ** ^If schema S of [database connection] D is not a [WAL mode] database ** that is in a read transaction, then [sqlite3_snapshot_get(D,S,P)] ** leaves the *P value unchanged and returns an appropriate [error code]. ** ** The [sqlite3_snapshot] object returned from a successful call to ** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] ** to avoid a memory leak. ** ** The [sqlite3_snapshot_get()] interface is only available when the ** SQLITE_ENABLE_SNAPSHOT compile-time option is used. */ SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( sqlite3 *db, const char *zSchema, sqlite3_snapshot **ppSnapshot ); /* ** CAPI3REF: Start a read transaction on an historical snapshot ** EXPERIMENTAL ** ** ^The [sqlite3_snapshot_open(D,S,P)] interface attempts to move the ** read transaction that is currently open on schema S of ** [database connection] D so that it refers to historical [snapshot] P. ** ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK on success ** or an appropriate [error code] if it fails. ** ** ^In order to succeed, a call to [sqlite3_snapshot_open(D,S,P)] must be ** the first operation, apart from other sqlite3_snapshot_open() calls, ** following the [BEGIN] that starts a new read transaction. ** ^A [snapshot] will fail to open if it has been overwritten by a ** [checkpoint]. ** ** The [sqlite3_snapshot_open()] interface is only available when the ** SQLITE_ENABLE_SNAPSHOT compile-time option is used. */ SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( sqlite3 *db, const char *zSchema, sqlite3_snapshot *pSnapshot ); /* ** CAPI3REF: Destroy a snapshot ** EXPERIMENTAL ** ** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. ** The application must eventually free every [sqlite3_snapshot] object ** using this routine to avoid a memory leak. ** ** The [sqlite3_snapshot_free()] interface is only available when the ** SQLITE_ENABLE_SNAPSHOT compile-time option is used. */ SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); /* ** Undo the hack that converts floating point types to integer for ** builds on processors without floating point support. */ #ifdef SQLITE_OMIT_FLOATING_POINT # undef double #endif #ifdef __cplusplus } /* End of the 'extern "C"' block */ #endif #endif /* _SQLITE3_H_ */ |
Changes to src/test1.c.
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2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 | return TCL_ERROR; } pVfs->xCurrentTimeInt64(pVfs, &t); Tcl_SetObjResult(interp, Tcl_NewWideIntObj(t)); return TCL_OK; } /* ** Usage: sqlite3_next_stmt DB STMT ** ** Return the next statment in sequence after STMT. */ static int test_next_stmt( void * clientData, | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 | return TCL_ERROR; } pVfs->xCurrentTimeInt64(pVfs, &t); Tcl_SetObjResult(interp, Tcl_NewWideIntObj(t)); return TCL_OK; } #ifdef SQLITE_ENABLE_SNAPSHOT /* ** Usage: sqlite3_snapshot_get DB DBNAME */ static int test_snapshot_get( void * clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[] ){ int rc; sqlite3 *db; char *zName; sqlite3_snapshot *pSnapshot = 0; if( objc!=3 ){ Tcl_WrongNumArgs(interp, 1, objv, "DB DBNAME"); return TCL_ERROR; } if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR; zName = Tcl_GetString(objv[2]); rc = sqlite3_snapshot_get(db, zName, &pSnapshot); if( rc!=SQLITE_OK ){ Tcl_SetObjResult(interp, Tcl_NewStringObj(sqlite3ErrName(rc), -1)); return TCL_ERROR; }else{ char zBuf[100]; if( sqlite3TestMakePointerStr(interp, zBuf, pSnapshot) ) return TCL_ERROR; Tcl_SetObjResult(interp, Tcl_NewStringObj(zBuf, -1)); } return TCL_OK; } #endif /* SQLITE_ENABLE_SNAPSHOT */ #ifdef SQLITE_ENABLE_SNAPSHOT /* ** Usage: sqlite3_snapshot_open DB DBNAME SNAPSHOT */ static int test_snapshot_open( void * clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[] ){ int rc; sqlite3 *db; char *zName; sqlite3_snapshot *pSnapshot; if( objc!=4 ){ Tcl_WrongNumArgs(interp, 1, objv, "DB DBNAME SNAPSHOT"); return TCL_ERROR; } if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR; zName = Tcl_GetString(objv[2]); pSnapshot = (sqlite3_snapshot*)sqlite3TestTextToPtr(Tcl_GetString(objv[3])); rc = sqlite3_snapshot_open(db, zName, pSnapshot); if( rc!=SQLITE_OK ){ Tcl_SetObjResult(interp, Tcl_NewStringObj(sqlite3ErrName(rc), -1)); return TCL_ERROR; } return TCL_OK; } #endif /* SQLITE_ENABLE_SNAPSHOT */ #ifdef SQLITE_ENABLE_SNAPSHOT /* ** Usage: sqlite3_snapshot_free SNAPSHOT */ static int test_snapshot_free( void * clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[] ){ sqlite3_snapshot *pSnapshot; if( objc!=2 ){ Tcl_WrongNumArgs(interp, 1, objv, "SNAPSHOT"); return TCL_ERROR; } pSnapshot = (sqlite3_snapshot*)sqlite3TestTextToPtr(Tcl_GetString(objv[1])); sqlite3_snapshot_free(pSnapshot); return TCL_OK; } #endif /* SQLITE_ENABLE_SNAPSHOT */ /* ** Usage: sqlite3_next_stmt DB STMT ** ** Return the next statment in sequence after STMT. */ static int test_next_stmt( void * clientData, |
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7079 7080 7081 7082 7083 7084 7085 7086 7087 7088 7089 7090 7091 7092 | { "sqlite3_stmt_scanstatus", test_stmt_scanstatus, 0 }, { "sqlite3_stmt_scanstatus_reset", test_stmt_scanstatus_reset, 0 }, #endif #ifdef SQLITE_ENABLE_SQLLOG { "sqlite3_config_sqllog", test_config_sqllog, 0 }, #endif { "vfs_current_time_int64", vfsCurrentTimeInt64, 0 }, }; static int bitmask_size = sizeof(Bitmask)*8; static int longdouble_size = sizeof(LONGDOUBLE_TYPE); int i; extern int sqlite3_sync_count, sqlite3_fullsync_count; extern int sqlite3_opentemp_count; extern int sqlite3_like_count; | > > > > > | 7167 7168 7169 7170 7171 7172 7173 7174 7175 7176 7177 7178 7179 7180 7181 7182 7183 7184 7185 | { "sqlite3_stmt_scanstatus", test_stmt_scanstatus, 0 }, { "sqlite3_stmt_scanstatus_reset", test_stmt_scanstatus_reset, 0 }, #endif #ifdef SQLITE_ENABLE_SQLLOG { "sqlite3_config_sqllog", test_config_sqllog, 0 }, #endif { "vfs_current_time_int64", vfsCurrentTimeInt64, 0 }, #ifdef SQLITE_ENABLE_SNAPSHOT { "sqlite3_snapshot_get", test_snapshot_get, 0 }, { "sqlite3_snapshot_open", test_snapshot_open, 0 }, { "sqlite3_snapshot_free", test_snapshot_free, 0 }, #endif }; static int bitmask_size = sizeof(Bitmask)*8; static int longdouble_size = sizeof(LONGDOUBLE_TYPE); int i; extern int sqlite3_sync_count, sqlite3_fullsync_count; extern int sqlite3_opentemp_count; extern int sqlite3_like_count; |
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Changes to src/test_config.c.
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138 139 140 141 142 143 144 145 146 147 148 149 150 151 | #endif #ifdef SQLITE_ENABLE_MEMSYS5 Tcl_SetVar2(interp, "sqlite_options", "mem5", "1", TCL_GLOBAL_ONLY); #else Tcl_SetVar2(interp, "sqlite_options", "mem5", "0", TCL_GLOBAL_ONLY); #endif #ifdef SQLITE_MUTEX_OMIT Tcl_SetVar2(interp, "sqlite_options", "mutex", "0", TCL_GLOBAL_ONLY); #else Tcl_SetVar2(interp, "sqlite_options", "mutex", "1", TCL_GLOBAL_ONLY); #endif | > > > > > > | 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 | #endif #ifdef SQLITE_ENABLE_MEMSYS5 Tcl_SetVar2(interp, "sqlite_options", "mem5", "1", TCL_GLOBAL_ONLY); #else Tcl_SetVar2(interp, "sqlite_options", "mem5", "0", TCL_GLOBAL_ONLY); #endif #ifdef SQLITE_ENABLE_SNAPSHOT Tcl_SetVar2(interp, "sqlite_options", "snapshot", "1", TCL_GLOBAL_ONLY); #else Tcl_SetVar2(interp, "sqlite_options", "snapshot", "0", TCL_GLOBAL_ONLY); #endif #ifdef SQLITE_MUTEX_OMIT Tcl_SetVar2(interp, "sqlite_options", "mutex", "0", TCL_GLOBAL_ONLY); #else Tcl_SetVar2(interp, "sqlite_options", "mutex", "1", TCL_GLOBAL_ONLY); #endif |
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Changes to src/wal.c.
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268 269 270 271 272 273 274 | ** returns SQLITE_CANTOPEN. */ #define WAL_MAX_VERSION 3007000 #define WALINDEX_MAX_VERSION 3007000 /* ** Indices of various locking bytes. WAL_NREADER is the number | | > | > > > | 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 | ** returns SQLITE_CANTOPEN. */ #define WAL_MAX_VERSION 3007000 #define WALINDEX_MAX_VERSION 3007000 /* ** Indices of various locking bytes. WAL_NREADER is the number ** of available reader locks and should be at least 3. The default ** is SQLITE_SHM_NLOCK==8 and WAL_NREADER==5. */ #define WAL_WRITE_LOCK 0 #define WAL_ALL_BUT_WRITE 1 #define WAL_CKPT_LOCK 1 #define WAL_RECOVER_LOCK 2 #define WAL_READ_LOCK(I) (3+(I)) #define WAL_NREADER (SQLITE_SHM_NLOCK-3) /* Object declarations */ typedef struct WalIndexHdr WalIndexHdr; typedef struct WalIterator WalIterator; typedef struct WalCkptInfo WalCkptInfo; /* ** The following object holds a copy of the wal-index header content. ** ** The actual header in the wal-index consists of two copies of this ** object followed by one instance of the WalCkptInfo object. ** For all versions of SQLite through 3.10.0 and probably beyond, ** the locking bytes (WalCkptInfo.aLock) start at offset 120 and ** the total header size is 136 bytes. ** ** The szPage value can be any power of 2 between 512 and 32768, inclusive. ** Or it can be 1 to represent a 65536-byte page. The latter case was ** added in 3.7.1 when support for 64K pages was added. */ struct WalIndexHdr { u32 iVersion; /* Wal-index version */ |
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320 321 322 323 324 325 326 327 328 329 330 331 332 333 | ** nBackfill is the number of frames in the WAL that have been written ** back into the database. (We call the act of moving content from WAL to ** database "backfilling".) The nBackfill number is never greater than ** WalIndexHdr.mxFrame. nBackfill can only be increased by threads ** holding the WAL_CKPT_LOCK lock (which includes a recovery thread). ** However, a WAL_WRITE_LOCK thread can move the value of nBackfill from ** mxFrame back to zero when the WAL is reset. ** ** There is one entry in aReadMark[] for each reader lock. If a reader ** holds read-lock K, then the value in aReadMark[K] is no greater than ** the mxFrame for that reader. The value READMARK_NOT_USED (0xffffffff) ** for any aReadMark[] means that entry is unused. aReadMark[0] is ** a special case; its value is never used and it exists as a place-holder ** to avoid having to offset aReadMark[] indexs by one. Readers holding | > > > > > > > > > > | 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 | ** nBackfill is the number of frames in the WAL that have been written ** back into the database. (We call the act of moving content from WAL to ** database "backfilling".) The nBackfill number is never greater than ** WalIndexHdr.mxFrame. nBackfill can only be increased by threads ** holding the WAL_CKPT_LOCK lock (which includes a recovery thread). ** However, a WAL_WRITE_LOCK thread can move the value of nBackfill from ** mxFrame back to zero when the WAL is reset. ** ** nBackfillAttempted is the largest value of nBackfill that a checkpoint ** has attempted to achieve. Normally nBackfill==nBackfillAtempted, however ** the nBackfillAttempted is set before any backfilling is done and the ** nBackfill is only set after all backfilling completes. So if a checkpoint ** crashes, nBackfillAttempted might be larger than nBackfill. The ** WalIndexHdr.mxFrame must never be less than nBackfillAttempted. ** ** The aLock[] field is a set of bytes used for locking. These bytes should ** never be read or written. ** ** There is one entry in aReadMark[] for each reader lock. If a reader ** holds read-lock K, then the value in aReadMark[K] is no greater than ** the mxFrame for that reader. The value READMARK_NOT_USED (0xffffffff) ** for any aReadMark[] means that entry is unused. aReadMark[0] is ** a special case; its value is never used and it exists as a place-holder ** to avoid having to offset aReadMark[] indexs by one. Readers holding |
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360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 | ** ** We assume that 32-bit loads are atomic and so no locks are needed in ** order to read from any aReadMark[] entries. */ struct WalCkptInfo { u32 nBackfill; /* Number of WAL frames backfilled into DB */ u32 aReadMark[WAL_NREADER]; /* Reader marks */ }; #define READMARK_NOT_USED 0xffffffff /* A block of WALINDEX_LOCK_RESERVED bytes beginning at ** WALINDEX_LOCK_OFFSET is reserved for locks. Since some systems ** only support mandatory file-locks, we do not read or write data ** from the region of the file on which locks are applied. */ | > > > < | | | 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 | ** ** We assume that 32-bit loads are atomic and so no locks are needed in ** order to read from any aReadMark[] entries. */ struct WalCkptInfo { u32 nBackfill; /* Number of WAL frames backfilled into DB */ u32 aReadMark[WAL_NREADER]; /* Reader marks */ u8 aLock[SQLITE_SHM_NLOCK]; /* Reserved space for locks */ u32 nBackfillAttempted; /* WAL frames perhaps written, or maybe not */ u32 notUsed0; /* Available for future enhancements */ }; #define READMARK_NOT_USED 0xffffffff /* A block of WALINDEX_LOCK_RESERVED bytes beginning at ** WALINDEX_LOCK_OFFSET is reserved for locks. Since some systems ** only support mandatory file-locks, we do not read or write data ** from the region of the file on which locks are applied. */ #define WALINDEX_LOCK_OFFSET (sizeof(WalIndexHdr)*2+offsetof(WalCkptInfo,aLock)) #define WALINDEX_HDR_SIZE (sizeof(WalIndexHdr)*2+sizeof(WalCkptInfo)) /* Size of header before each frame in wal */ #define WAL_FRAME_HDRSIZE 24 /* Size of write ahead log header, including checksum. */ /* #define WAL_HDRSIZE 24 */ #define WAL_HDRSIZE 32 |
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430 431 432 433 434 435 436 437 438 439 440 441 442 443 | WalIndexHdr hdr; /* Wal-index header for current transaction */ u32 minFrame; /* Ignore wal frames before this one */ const char *zWalName; /* Name of WAL file */ u32 nCkpt; /* Checkpoint sequence counter in the wal-header */ #ifdef SQLITE_DEBUG u8 lockError; /* True if a locking error has occurred */ #endif }; /* ** Candidate values for Wal.exclusiveMode. */ #define WAL_NORMAL_MODE 0 #define WAL_EXCLUSIVE_MODE 1 | > > > | 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 | WalIndexHdr hdr; /* Wal-index header for current transaction */ u32 minFrame; /* Ignore wal frames before this one */ const char *zWalName; /* Name of WAL file */ u32 nCkpt; /* Checkpoint sequence counter in the wal-header */ #ifdef SQLITE_DEBUG u8 lockError; /* True if a locking error has occurred */ #endif #ifdef SQLITE_ENABLE_SNAPSHOT WalIndexHdr *pSnapshot; /* Start transaction here if not NULL */ #endif }; /* ** Candidate values for Wal.exclusiveMode. */ #define WAL_NORMAL_MODE 0 #define WAL_EXCLUSIVE_MODE 1 |
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1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 | /* Reset the checkpoint-header. This is safe because this thread is ** currently holding locks that exclude all other readers, writers and ** checkpointers. */ pInfo = walCkptInfo(pWal); pInfo->nBackfill = 0; pInfo->aReadMark[0] = 0; for(i=1; i<WAL_NREADER; i++) pInfo->aReadMark[i] = READMARK_NOT_USED; if( pWal->hdr.mxFrame ) pInfo->aReadMark[1] = pWal->hdr.mxFrame; /* If more than one frame was recovered from the log file, report an ** event via sqlite3_log(). This is to help with identifying performance ** problems caused by applications routinely shutting down without | > | 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 | /* Reset the checkpoint-header. This is safe because this thread is ** currently holding locks that exclude all other readers, writers and ** checkpointers. */ pInfo = walCkptInfo(pWal); pInfo->nBackfill = 0; pInfo->nBackfillAttempted = pWal->hdr.mxFrame; pInfo->aReadMark[0] = 0; for(i=1; i<WAL_NREADER; i++) pInfo->aReadMark[i] = READMARK_NOT_USED; if( pWal->hdr.mxFrame ) pInfo->aReadMark[1] = pWal->hdr.mxFrame; /* If more than one frame was recovered from the log file, report an ** event via sqlite3_log(). This is to help with identifying performance ** problems caused by applications routinely shutting down without |
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1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 | assert( zWalName && zWalName[0] ); assert( pDbFd ); /* In the amalgamation, the os_unix.c and os_win.c source files come before ** this source file. Verify that the #defines of the locking byte offsets ** in os_unix.c and os_win.c agree with the WALINDEX_LOCK_OFFSET value. */ #ifdef WIN_SHM_BASE assert( WIN_SHM_BASE==WALINDEX_LOCK_OFFSET ); #endif #ifdef UNIX_SHM_BASE assert( UNIX_SHM_BASE==WALINDEX_LOCK_OFFSET ); #endif | > > > > | 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 | assert( zWalName && zWalName[0] ); assert( pDbFd ); /* In the amalgamation, the os_unix.c and os_win.c source files come before ** this source file. Verify that the #defines of the locking byte offsets ** in os_unix.c and os_win.c agree with the WALINDEX_LOCK_OFFSET value. ** For that matter, if the lock offset ever changes from its initial design ** value of 120, we need to know that so there is an assert() to check it. */ assert( 120==WALINDEX_LOCK_OFFSET ); assert( 136==WALINDEX_HDR_SIZE ); #ifdef WIN_SHM_BASE assert( WIN_SHM_BASE==WALINDEX_LOCK_OFFSET ); #endif #ifdef UNIX_SHM_BASE assert( UNIX_SHM_BASE==WALINDEX_LOCK_OFFSET ); #endif |
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1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 | u32 *aSalt = pWal->hdr.aSalt; /* Big-endian salt values */ pWal->nCkpt++; pWal->hdr.mxFrame = 0; sqlite3Put4byte((u8*)&aSalt[0], 1 + sqlite3Get4byte((u8*)&aSalt[0])); memcpy(&pWal->hdr.aSalt[1], &salt1, 4); walIndexWriteHdr(pWal); pInfo->nBackfill = 0; pInfo->aReadMark[1] = 0; for(i=2; i<WAL_NREADER; i++) pInfo->aReadMark[i] = READMARK_NOT_USED; assert( pInfo->aReadMark[0]==0 ); } /* ** Copy as much content as we can from the WAL back into the database file | > | 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 | u32 *aSalt = pWal->hdr.aSalt; /* Big-endian salt values */ pWal->nCkpt++; pWal->hdr.mxFrame = 0; sqlite3Put4byte((u8*)&aSalt[0], 1 + sqlite3Get4byte((u8*)&aSalt[0])); memcpy(&pWal->hdr.aSalt[1], &salt1, 4); walIndexWriteHdr(pWal); pInfo->nBackfill = 0; pInfo->nBackfillAttempted = 0; pInfo->aReadMark[1] = 0; for(i=2; i<WAL_NREADER; i++) pInfo->aReadMark[i] = READMARK_NOT_USED; assert( pInfo->aReadMark[0]==0 ); } /* ** Copy as much content as we can from the WAL back into the database file |
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1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 | } if( pInfo->nBackfill<mxSafeFrame && (rc = walBusyLock(pWal, xBusy, pBusyArg, WAL_READ_LOCK(0),1))==SQLITE_OK ){ i64 nSize; /* Current size of database file */ u32 nBackfill = pInfo->nBackfill; /* Sync the WAL to disk */ if( sync_flags ){ rc = sqlite3OsSync(pWal->pWalFd, sync_flags); } /* If the database may grow as a result of this checkpoint, hint | > > | 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 | } if( pInfo->nBackfill<mxSafeFrame && (rc = walBusyLock(pWal, xBusy, pBusyArg, WAL_READ_LOCK(0),1))==SQLITE_OK ){ i64 nSize; /* Current size of database file */ u32 nBackfill = pInfo->nBackfill; pInfo->nBackfillAttempted = mxSafeFrame; /* Sync the WAL to disk */ if( sync_flags ){ rc = sqlite3OsSync(pWal->pWalFd, sync_flags); } /* If the database may grow as a result of this checkpoint, hint |
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2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 | */ static int walTryBeginRead(Wal *pWal, int *pChanged, int useWal, int cnt){ volatile WalCkptInfo *pInfo; /* Checkpoint information in wal-index */ u32 mxReadMark; /* Largest aReadMark[] value */ int mxI; /* Index of largest aReadMark[] value */ int i; /* Loop counter */ int rc = SQLITE_OK; /* Return code */ assert( pWal->readLock<0 ); /* Not currently locked */ /* Take steps to avoid spinning forever if there is a protocol error. ** ** Circumstances that cause a RETRY should only last for the briefest ** instances of time. No I/O or other system calls are done while the | > | 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 | */ static int walTryBeginRead(Wal *pWal, int *pChanged, int useWal, int cnt){ volatile WalCkptInfo *pInfo; /* Checkpoint information in wal-index */ u32 mxReadMark; /* Largest aReadMark[] value */ int mxI; /* Index of largest aReadMark[] value */ int i; /* Loop counter */ int rc = SQLITE_OK; /* Return code */ u32 mxFrame; /* Wal frame to lock to */ assert( pWal->readLock<0 ); /* Not currently locked */ /* Take steps to avoid spinning forever if there is a protocol error. ** ** Circumstances that cause a RETRY should only last for the briefest ** instances of time. No I/O or other system calls are done while the |
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2206 2207 2208 2209 2210 2211 2212 | } if( rc!=SQLITE_OK ){ return rc; } } pInfo = walCkptInfo(pWal); | | > > > > > | 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 | } if( rc!=SQLITE_OK ){ return rc; } } pInfo = walCkptInfo(pWal); if( !useWal && pInfo->nBackfill==pWal->hdr.mxFrame #ifdef SQLITE_ENABLE_SNAPSHOT && (pWal->pSnapshot==0 || pWal->hdr.mxFrame==0 || 0==memcmp(&pWal->hdr, pWal->pSnapshot, sizeof(WalIndexHdr))) #endif ){ /* The WAL has been completely backfilled (or it is empty). ** and can be safely ignored. */ rc = walLockShared(pWal, WAL_READ_LOCK(0)); walShmBarrier(pWal); if( rc==SQLITE_OK ){ if( memcmp((void *)walIndexHdr(pWal), &pWal->hdr, sizeof(WalIndexHdr)) ){ |
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2244 2245 2246 2247 2248 2249 2250 2251 2252 | /* If we get this far, it means that the reader will want to use ** the WAL to get at content from recent commits. The job now is ** to select one of the aReadMark[] entries that is closest to ** but not exceeding pWal->hdr.mxFrame and lock that entry. */ mxReadMark = 0; mxI = 0; for(i=1; i<WAL_NREADER; i++){ u32 thisMark = pInfo->aReadMark[i]; | > > > > > > | < < | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | < | 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 | /* If we get this far, it means that the reader will want to use ** the WAL to get at content from recent commits. The job now is ** to select one of the aReadMark[] entries that is closest to ** but not exceeding pWal->hdr.mxFrame and lock that entry. */ mxReadMark = 0; mxI = 0; mxFrame = pWal->hdr.mxFrame; #ifdef SQLITE_ENABLE_SNAPSHOT if( pWal->pSnapshot && pWal->pSnapshot->mxFrame<mxFrame ){ mxFrame = pWal->pSnapshot->mxFrame; } #endif for(i=1; i<WAL_NREADER; i++){ u32 thisMark = pInfo->aReadMark[i]; if( mxReadMark<=thisMark && thisMark<=mxFrame ){ assert( thisMark!=READMARK_NOT_USED ); mxReadMark = thisMark; mxI = i; } } if( (pWal->readOnly & WAL_SHM_RDONLY)==0 && (mxReadMark<mxFrame || mxI==0) ){ for(i=1; i<WAL_NREADER; i++){ rc = walLockExclusive(pWal, WAL_READ_LOCK(i), 1); if( rc==SQLITE_OK ){ mxReadMark = pInfo->aReadMark[i] = mxFrame; mxI = i; walUnlockExclusive(pWal, WAL_READ_LOCK(i), 1); break; }else if( rc!=SQLITE_BUSY ){ return rc; } } } if( mxI==0 ){ assert( rc==SQLITE_BUSY || (pWal->readOnly & WAL_SHM_RDONLY)!=0 ); return rc==SQLITE_BUSY ? WAL_RETRY : SQLITE_READONLY_CANTLOCK; } rc = walLockShared(pWal, WAL_READ_LOCK(mxI)); if( rc ){ return rc==SQLITE_BUSY ? WAL_RETRY : rc; } /* Now that the read-lock has been obtained, check that neither the ** value in the aReadMark[] array or the contents of the wal-index ** header have changed. ** ** It is necessary to check that the wal-index header did not change ** between the time it was read and when the shared-lock was obtained ** on WAL_READ_LOCK(mxI) was obtained to account for the possibility ** that the log file may have been wrapped by a writer, or that frames ** that occur later in the log than pWal->hdr.mxFrame may have been ** copied into the database by a checkpointer. If either of these things ** happened, then reading the database with the current value of ** pWal->hdr.mxFrame risks reading a corrupted snapshot. So, retry ** instead. ** ** Before checking that the live wal-index header has not changed ** since it was read, set Wal.minFrame to the first frame in the wal ** file that has not yet been checkpointed. This client will not need ** to read any frames earlier than minFrame from the wal file - they ** can be safely read directly from the database file. ** ** Because a ShmBarrier() call is made between taking the copy of ** nBackfill and checking that the wal-header in shared-memory still ** matches the one cached in pWal->hdr, it is guaranteed that the ** checkpointer that set nBackfill was not working with a wal-index ** header newer than that cached in pWal->hdr. If it were, that could ** cause a problem. The checkpointer could omit to checkpoint ** a version of page X that lies before pWal->minFrame (call that version ** A) on the basis that there is a newer version (version B) of the same ** page later in the wal file. But if version B happens to like past ** frame pWal->hdr.mxFrame - then the client would incorrectly assume ** that it can read version A from the database file. However, since ** we can guarantee that the checkpointer that set nBackfill could not ** see any pages past pWal->hdr.mxFrame, this problem does not come up. */ pWal->minFrame = pInfo->nBackfill+1; walShmBarrier(pWal); if( pInfo->aReadMark[mxI]!=mxReadMark || memcmp((void *)walIndexHdr(pWal), &pWal->hdr, sizeof(WalIndexHdr)) ){ walUnlockShared(pWal, WAL_READ_LOCK(mxI)); return WAL_RETRY; }else{ assert( mxReadMark<=pWal->hdr.mxFrame ); pWal->readLock = (i16)mxI; } return rc; } /* ** Begin a read transaction on the database. ** |
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2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 | ** Pager layer will use this to know that is cache is stale and ** needs to be flushed. */ int sqlite3WalBeginReadTransaction(Wal *pWal, int *pChanged){ int rc; /* Return code */ int cnt = 0; /* Number of TryBeginRead attempts */ do{ rc = walTryBeginRead(pWal, pChanged, 0, ++cnt); }while( rc==WAL_RETRY ); testcase( (rc&0xff)==SQLITE_BUSY ); testcase( (rc&0xff)==SQLITE_IOERR ); testcase( rc==SQLITE_PROTOCOL ); testcase( rc==SQLITE_OK ); return rc; } /* ** Finish with a read transaction. All this does is release the ** read-lock. */ | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 | ** Pager layer will use this to know that is cache is stale and ** needs to be flushed. */ int sqlite3WalBeginReadTransaction(Wal *pWal, int *pChanged){ int rc; /* Return code */ int cnt = 0; /* Number of TryBeginRead attempts */ #ifdef SQLITE_ENABLE_SNAPSHOT int bChanged = 0; WalIndexHdr *pSnapshot = pWal->pSnapshot; if( pSnapshot && memcmp(pSnapshot, &pWal->hdr, sizeof(WalIndexHdr))!=0 ){ bChanged = 1; } #endif do{ rc = walTryBeginRead(pWal, pChanged, 0, ++cnt); }while( rc==WAL_RETRY ); testcase( (rc&0xff)==SQLITE_BUSY ); testcase( (rc&0xff)==SQLITE_IOERR ); testcase( rc==SQLITE_PROTOCOL ); testcase( rc==SQLITE_OK ); #ifdef SQLITE_ENABLE_SNAPSHOT if( rc==SQLITE_OK ){ if( pSnapshot && memcmp(pSnapshot, &pWal->hdr, sizeof(WalIndexHdr))!=0 ){ /* At this point the client has a lock on an aReadMark[] slot holding ** a value equal to or smaller than pSnapshot->mxFrame, but pWal->hdr ** is populated with the wal-index header corresponding to the head ** of the wal file. Verify that pSnapshot is still valid before ** continuing. Reasons why pSnapshot might no longer be valid: ** ** (1) The WAL file has been reset since the snapshot was taken. ** In this case, the salt will have changed. ** ** (2) A checkpoint as been attempted that wrote frames past ** pSnapshot->mxFrame into the database file. Note that the ** checkpoint need not have completed for this to cause problems. */ volatile WalCkptInfo *pInfo = walCkptInfo(pWal); assert( pWal->readLock>0 || pWal->hdr.mxFrame==0 ); assert( pInfo->aReadMark[pWal->readLock]<=pSnapshot->mxFrame ); /* It is possible that there is a checkpointer thread running ** concurrent with this code. If this is the case, it may be that the ** checkpointer has already determined that it will checkpoint ** snapshot X, where X is later in the wal file than pSnapshot, but ** has not yet set the pInfo->nBackfillAttempted variable to indicate ** its intent. To avoid the race condition this leads to, ensure that ** there is no checkpointer process by taking a shared CKPT lock ** before checking pInfo->nBackfillAttempted. */ rc = walLockShared(pWal, WAL_CKPT_LOCK); if( rc==SQLITE_OK ){ /* Check that the wal file has not been wrapped. Assuming that it has ** not, also check that no checkpointer has attempted to checkpoint any ** frames beyond pSnapshot->mxFrame. If either of these conditions are ** true, return SQLITE_BUSY_SNAPSHOT. Otherwise, overwrite pWal->hdr ** with *pSnapshot and set *pChanged as appropriate for opening the ** snapshot. */ if( !memcmp(pSnapshot->aSalt, pWal->hdr.aSalt, sizeof(pWal->hdr.aSalt)) && pSnapshot->mxFrame>=pInfo->nBackfillAttempted ){ memcpy(&pWal->hdr, pSnapshot, sizeof(WalIndexHdr)); *pChanged = bChanged; }else{ rc = SQLITE_BUSY_SNAPSHOT; } /* Release the shared CKPT lock obtained above. */ walUnlockShared(pWal, WAL_CKPT_LOCK); } if( rc!=SQLITE_OK ){ sqlite3WalEndReadTransaction(pWal); } } } #endif return rc; } /* ** Finish with a read transaction. All this does is release the ** read-lock. */ |
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3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 | ** heap-memory for the wal-index. Otherwise, if the argument is NULL or the ** WAL module is using shared-memory, return false. */ int sqlite3WalHeapMemory(Wal *pWal){ return (pWal && pWal->exclusiveMode==WAL_HEAPMEMORY_MODE ); } #ifdef SQLITE_ENABLE_ZIPVFS /* ** If the argument is not NULL, it points to a Wal object that holds a ** read-lock. This function returns the database page-size if it is known, ** or zero if it is not (or if pWal is NULL). */ int sqlite3WalFramesize(Wal *pWal){ assert( pWal==0 || pWal->readLock>=0 ); return (pWal ? pWal->szPage : 0); } #endif #endif /* #ifndef SQLITE_OMIT_WAL */ | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 | ** heap-memory for the wal-index. Otherwise, if the argument is NULL or the ** WAL module is using shared-memory, return false. */ int sqlite3WalHeapMemory(Wal *pWal){ return (pWal && pWal->exclusiveMode==WAL_HEAPMEMORY_MODE ); } #ifdef SQLITE_ENABLE_SNAPSHOT /* Create a snapshot object. The content of a snapshot is opaque to ** every other subsystem, so the WAL module can put whatever it needs ** in the object. */ int sqlite3WalSnapshotGet(Wal *pWal, sqlite3_snapshot **ppSnapshot){ int rc = SQLITE_OK; WalIndexHdr *pRet; assert( pWal->readLock>=0 && pWal->writeLock==0 ); pRet = (WalIndexHdr*)sqlite3_malloc(sizeof(WalIndexHdr)); if( pRet==0 ){ rc = SQLITE_NOMEM; }else{ memcpy(pRet, &pWal->hdr, sizeof(WalIndexHdr)); *ppSnapshot = (sqlite3_snapshot*)pRet; } return rc; } /* Try to open on pSnapshot when the next read-transaction starts */ void sqlite3WalSnapshotOpen(Wal *pWal, sqlite3_snapshot *pSnapshot){ pWal->pSnapshot = (WalIndexHdr*)pSnapshot; } #endif /* SQLITE_ENABLE_SNAPSHOT */ #ifdef SQLITE_ENABLE_ZIPVFS /* ** If the argument is not NULL, it points to a Wal object that holds a ** read-lock. This function returns the database page-size if it is known, ** or zero if it is not (or if pWal is NULL). */ int sqlite3WalFramesize(Wal *pWal){ assert( pWal==0 || pWal->readLock>=0 ); return (pWal ? pWal->szPage : 0); } #endif #endif /* #ifndef SQLITE_OMIT_WAL */ |
Changes to src/wal.h.
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121 122 123 124 125 126 127 128 129 130 131 132 133 134 | int sqlite3WalExclusiveMode(Wal *pWal, int op); /* Return true if the argument is non-NULL and the WAL module is using ** heap-memory for the wal-index. Otherwise, if the argument is NULL or the ** WAL module is using shared-memory, return false. */ int sqlite3WalHeapMemory(Wal *pWal); #ifdef SQLITE_ENABLE_ZIPVFS /* If the WAL file is not empty, return the number of bytes of content ** stored in each frame (i.e. the db page-size when the WAL was created). */ int sqlite3WalFramesize(Wal *pWal); #endif | > > > > > | 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 | int sqlite3WalExclusiveMode(Wal *pWal, int op); /* Return true if the argument is non-NULL and the WAL module is using ** heap-memory for the wal-index. Otherwise, if the argument is NULL or the ** WAL module is using shared-memory, return false. */ int sqlite3WalHeapMemory(Wal *pWal); #ifdef SQLITE_ENABLE_SNAPSHOT int sqlite3WalSnapshotGet(Wal *pWal, sqlite3_snapshot **ppSnapshot); void sqlite3WalSnapshotOpen(Wal *pWal, sqlite3_snapshot *pSnapshot); #endif #ifdef SQLITE_ENABLE_ZIPVFS /* If the WAL file is not empty, return the number of bytes of content ** stored in each frame (i.e. the db page-size when the WAL was created). */ int sqlite3WalFramesize(Wal *pWal); #endif |
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Added test/snapshot.test.
> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 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 | # 2015 December 7 # # 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 implements regression tests for SQLite library. The focus # of this file is the sqlite3_snapshot_xxx() APIs. # set testdir [file dirname $argv0] source $testdir/tester.tcl ifcapable !snapshot {finish_test; return} set testprefix snapshot #------------------------------------------------------------------------- # Check some error conditions in snapshot_get(). It is an error if: # # 1) snapshot_get() is called on a non-WAL database, or # 2) there is an open write transaction on the database. # do_execsql_test 1.0 { CREATE TABLE t1(a, b); INSERT INTO t1 VALUES(1, 2); INSERT INTO t1 VALUES(3, 4); } do_test 1.1.1 { execsql { BEGIN; SELECT * FROM t1; } list [catch { sqlite3_snapshot_get db main } msg] $msg } {1 SQLITE_ERROR} do_execsql_test 1.1.2 COMMIT do_test 1.2.1 { execsql { PRAGMA journal_mode = WAL; BEGIN; INSERT INTO t1 VALUES(5, 6); INSERT INTO t1 VALUES(7, 8); } list [catch { sqlite3_snapshot_get db main } msg] $msg } {1 SQLITE_ERROR} do_execsql_test 1.3.2 COMMIT #------------------------------------------------------------------------- # Check that a simple case works. Reuse the database created by the # block of tests above. # do_execsql_test 2.1.0 { BEGIN; SELECT * FROM t1; } {1 2 3 4 5 6 7 8} breakpoint do_test 2.1.1 { set snapshot [sqlite3_snapshot_get db main] execsql { COMMIT; INSERT INTO t1 VALUES(9, 10); SELECT * FROM t1; } } {1 2 3 4 5 6 7 8 9 10} do_test 2.1.2 { execsql BEGIN sqlite3_snapshot_open db main $snapshot execsql { SELECT * FROM t1; } } {1 2 3 4 5 6 7 8} do_test 2.1.3 { sqlite3_snapshot_free $snapshot execsql COMMIT } {} do_test 2.2.0 { sqlite3 db2 test.db execsql { BEGIN; SELECT * FROM t1; } db2 } {1 2 3 4 5 6 7 8 9 10} do_test 2.2.1 { set snapshot [sqlite3_snapshot_get db2 main] execsql { INSERT INTO t1 VALUES(11, 12); SELECT * FROM t1; } } {1 2 3 4 5 6 7 8 9 10 11 12} do_test 2.2.2 { execsql BEGIN sqlite3_snapshot_open db main $snapshot execsql { SELECT * FROM t1; } } {1 2 3 4 5 6 7 8 9 10} do_test 2.2.3 { sqlite3_snapshot_free $snapshot execsql COMMIT execsql COMMIT db2 db2 close } {} do_test 2.3.1 { execsql { DELETE FROM t1 WHERE a>6 } set snapshot [sqlite3_snapshot_get db main] execsql { INSERT INTO t1 VALUES('a', 'b'); INSERT INTO t1 VALUES('c', 'd'); SELECT * FROM t1; } } {1 2 3 4 5 6 a b c d} do_test 2.3.2 { execsql BEGIN sqlite3_snapshot_open db main $snapshot execsql { SELECT * FROM t1 } } {1 2 3 4 5 6} do_test 2.3.3 { catchsql { INSERT INTO t1 VALUES('x','y') } } {1 {database is locked}} do_test 2.3.4 { execsql COMMIT sqlite3_snapshot_free $snapshot } {} #------------------------------------------------------------------------- # Check some errors in sqlite3_snapshot_open(). It is an error if: # # 1) the db is in auto-commit mode, # 2) the db has an open (read or write) transaction, # 3) the db is not a wal database, # # Reuse the database created by earlier tests. # do_execsql_test 3.0.0 { CREATE TABLE t2(x, y); INSERT INTO t2 VALUES('a', 'b'); INSERT INTO t2 VALUES('c', 'd'); BEGIN; SELECT * FROM t2; } {a b c d} do_test 3.0.1 { set snapshot [sqlite3_snapshot_get db main] execsql { COMMIT } execsql { INSERT INTO t2 VALUES('e', 'f'); } } {} do_test 3.1 { list [catch {sqlite3_snapshot_open db main $snapshot } msg] $msg } {1 SQLITE_ERROR} do_test 3.2.1 { execsql { BEGIN; SELECT * FROM t2; } } {a b c d e f} do_test 3.2.2 { list [catch {sqlite3_snapshot_open db main $snapshot } msg] $msg } {1 SQLITE_ERROR} do_test 3.2.3 { execsql { COMMIT; BEGIN; INSERT INTO t2 VALUES('g', 'h'); } list [catch {sqlite3_snapshot_open db main $snapshot } msg] $msg } {1 SQLITE_ERROR} do_execsql_test 3.2.4 COMMIT do_test 3.3.1 { execsql { PRAGMA journal_mode = DELETE } execsql { BEGIN } list [catch {sqlite3_snapshot_open db main $snapshot } msg] $msg } {1 SQLITE_ERROR} do_test 3.3.2 { sqlite3_snapshot_free $snapshot execsql COMMIT } {} #------------------------------------------------------------------------- # Check that SQLITE_BUSY_SNAPSHOT is returned if the specified snapshot # no longer exists because the wal file has been checkpointed. # # 1. Reading a snapshot from the middle of a wal file is not possible # after the wal file has been checkpointed. # # 2. That a snapshot from the end of a wal file can not be read once # the wal file has been wrapped. # do_execsql_test 4.1.0 { PRAGMA journal_mode = wal; CREATE TABLE t3(i, j); INSERT INTO t3 VALUES('o', 't'); INSERT INTO t3 VALUES('t', 'f'); BEGIN; SELECT * FROM t3; } {wal o t t f} do_test 4.1.1 { set snapshot [sqlite3_snapshot_get db main] execsql COMMIT } {} do_test 4.1.2 { execsql { INSERT INTO t3 VALUES('f', 's'); BEGIN; } sqlite3_snapshot_open db main $snapshot execsql { SELECT * FROM t3 } } {o t t f} do_test 4.1.3 { execsql { COMMIT; PRAGMA wal_checkpoint; BEGIN; } list [catch {sqlite3_snapshot_open db main $snapshot} msg] $msg } {1 SQLITE_BUSY_SNAPSHOT} do_test 4.1.4 { sqlite3_snapshot_free $snapshot execsql COMMIT } {} do_test 4.2.1 { execsql { INSERT INTO t3 VALUES('s', 'e'); INSERT INTO t3 VALUES('n', 't'); BEGIN; SELECT * FROM t3; } } {o t t f f s s e n t} do_test 4.2.2 { set snapshot [sqlite3_snapshot_get db main] execsql { COMMIT; PRAGMA wal_checkpoint; BEGIN; } sqlite3_snapshot_open db main $snapshot execsql { SELECT * FROM t3 } } {o t t f f s s e n t} do_test 4.2.3 { execsql { COMMIT; INSERT INTO t3 VALUES('e', 't'); BEGIN; } list [catch {sqlite3_snapshot_open db main $snapshot} msg] $msg } {1 SQLITE_BUSY_SNAPSHOT} do_test 4.2.4 { sqlite3_snapshot_free $snapshot } {} #------------------------------------------------------------------------- # Check that SQLITE_BUSY is returned if a checkpoint is running when # sqlite3_snapshot_open() is called. # reset_db db close testvfs tvfs sqlite3 db test.db -vfs tvfs do_execsql_test 5.1 { PRAGMA journal_mode = wal; CREATE TABLE x1(x, xx, xxx); INSERT INTO x1 VALUES('z', 'zz', 'zzz'); BEGIN; SELECT * FROM x1; } {wal z zz zzz} do_test 5.2 { set ::snapshot [sqlite3_snapshot_get db main] sqlite3 db2 test.db -vfs tvfs execsql { INSERT INTO x1 VALUES('a', 'aa', 'aaa'); COMMIT; } } {} set t53 0 proc write_callback {args} { do_test 5.3.[incr ::t53] { execsql BEGIN list [catch { sqlite3_snapshot_open db main $::snapshot } msg] $msg } {1 SQLITE_BUSY} catchsql COMMIT } tvfs filter xWrite tvfs script write_callback db2 eval { PRAGMA wal_checkpoint } db close db2 close tvfs delete sqlite3_snapshot_free $snapshot #------------------------------------------------------------------------- # Test that sqlite3_snapshot_get() may be called immediately after # "BEGIN; PRAGMA user_version;". And that sqlite3_snapshot_open() may # be called after opening the db handle and running the script # "PRAGMA user_version; BEGIN". reset_db do_execsql_test 6.1 { PRAGMA journal_mode = wal; CREATE TABLE x1(x, xx, xxx); INSERT INTO x1 VALUES('z', 'zz', 'zzz'); BEGIN; PRAGMA user_version; } {wal 0} do_test 6.2 { set ::snapshot [sqlite3_snapshot_get db main] execsql { INSERT INTO x1 VALUES('a', 'aa', 'aaa'); COMMIT; } } {} do_test 6.3 { sqlite3 db2 test.db db2 eval "PRAGMA user_version ; BEGIN" sqlite3_snapshot_open db2 main $::snapshot db2 eval { SELECT * FROM x1 } } {z zz zzz} sqlite3_snapshot_free $snapshot finish_test |
Added test/snapshot_fault.test.
> > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 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 | # 2015 December 10 # # 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 implements regression tests for SQLite library. The focus # of this file is the sqlite3_snapshot_xxx() APIs. # set testdir [file dirname $argv0] source $testdir/tester.tcl ifcapable !snapshot {finish_test; return} set testprefix snapshot_fault #------------------------------------------------------------------------- # Check that an sqlite3_snapshot_open() client cannot be tricked into # reading a corrupt snapshot even if a second client fails while # checkpointing the db. # do_faultsim_test 1.0 -prep { faultsim_delete_and_reopen sqlite3 db2 test.db db2 eval { CREATE TABLE t1(a, b UNIQUE, c UNIQUE); INSERT INTO t1 VALUES(1, randomblob(500), randomblob(500)); INSERT INTO t1 VALUES(2, randomblob(500), randomblob(500)); PRAGMA journal_mode = wal; INSERT INTO t1 VALUES(3, randomblob(500), randomblob(500)); BEGIN; SELECT a FROM t1; } set ::snapshot [sqlite3_snapshot_get db2 main] db2 eval COMMIT db2 eval { UPDATE t1 SET b=randomblob(501), c=randomblob(501) WHERE a=1; INSERT INTO t1 VALUES(4, randomblob(500), randomblob(500)); INSERT INTO t1 VALUES(5, randomblob(500), randomblob(500)); INSERT INTO t1 VALUES(6, randomblob(500), randomblob(500)); } } -body { db eval { PRAGMA wal_checkpoint } } -test { db2 eval BEGIN if {[catch { sqlite3_snapshot_open db2 main $::snapshot } msg]} { if {$msg != "SQLITE_BUSY_SNAPSHOT" && $msg != "SQLITE_BUSY"} { error "error is $msg" } } else { set res [db2 eval { SELECT a FROM t1; PRAGMA integrity_check; }] if {$res != "1 2 3 ok"} { error "res is $res" } } sqlite3_snapshot_free $::snapshot } #------------------------------------------------------------------------- # This test is similar to the previous one. Except, after the # "PRAGMA wal_checkpoint" command fails the db is closed and reopened # so as to require wal file recovery. It should not be possible to open # a snapshot that is part of the body of a recovered wal file. # do_faultsim_test 2.0 -prep { faultsim_delete_and_reopen db eval { CREATE TABLE t1(a, b UNIQUE, c UNIQUE); INSERT INTO t1 VALUES(1, randomblob(500), randomblob(500)); INSERT INTO t1 VALUES(2, randomblob(500), randomblob(500)); PRAGMA journal_mode = wal; INSERT INTO t1 VALUES(3, randomblob(500), randomblob(500)); BEGIN; SELECT a FROM t1; } set ::snapshot [sqlite3_snapshot_get db main] db eval COMMIT db eval { UPDATE t1 SET b=randomblob(501), c=randomblob(501) WHERE a=1; INSERT INTO t1 VALUES(4, randomblob(500), randomblob(500)); INSERT INTO t1 VALUES(5, randomblob(500), randomblob(500)); INSERT INTO t1 VALUES(6, randomblob(500), randomblob(500)); } } -body { db eval { PRAGMA wal_checkpoint } } -test { db_save db close db_restore_and_reopen db eval { SELECT * FROM t1 } db eval BEGIN if {[catch { sqlite3_snapshot_open db main $::snapshot } msg]} { if {$msg != "SQLITE_BUSY_SNAPSHOT" && $msg != "SQLITE_BUSY"} { error "error is $msg" } } else { # This branch should actually never be taken. But it was useful in # determining whether or not this test was actually working (by # running a modified version of SQLite that allowed snapshots to be # opened following a recovery). error "TEST HAS FAILED" set res [db eval { SELECT a FROM t1; PRAGMA integrity_check; }] if {$res != "1 2 3 ok"} { error "res is $res" } } sqlite3_snapshot_free $::snapshot } #------------------------------------------------------------------------- # Test the handling of faults that occur within sqlite3_snapshot_open(). # do_faultsim_test 3.0 -prep { faultsim_delete_and_reopen db eval { CREATE TABLE t1(a, b UNIQUE, c UNIQUE); INSERT INTO t1 VALUES(1, randomblob(500), randomblob(500)); INSERT INTO t1 VALUES(2, randomblob(500), randomblob(500)); PRAGMA journal_mode = wal; INSERT INTO t1 VALUES(3, randomblob(500), randomblob(500)); BEGIN; SELECT a FROM t1; } set ::snapshot [sqlite3_snapshot_get db main] db eval COMMIT db eval { UPDATE t1 SET b=randomblob(501), c=randomblob(501) WHERE a=1; INSERT INTO t1 VALUES(4, randomblob(500), randomblob(500)); INSERT INTO t1 VALUES(5, randomblob(500), randomblob(500)); INSERT INTO t1 VALUES(6, randomblob(500), randomblob(500)); BEGIN; } } -body { if { [catch { sqlite3_snapshot_open db main $::snapshot } msg] } { error $msg } } -test { faultsim_test_result {0 {}} {1 SQLITE_IOERR} \ {1 SQLITE_IOERR_NOMEM} {1 SQLITE_IOERR_READ} if {$testrc==0} { set res [db eval { SELECT a FROM t1; PRAGMA integrity_check; }] if {$res != "1 2 3 ok"} { error "res is $res" } } sqlite3_snapshot_free $::snapshot } finish_test |