Index: third_party/sqlite/sqlite-src-3070603/src/vacuum.c |
diff --git a/third_party/sqlite/sqlite-src-3070603/src/vacuum.c b/third_party/sqlite/sqlite-src-3070603/src/vacuum.c |
new file mode 100644 |
index 0000000000000000000000000000000000000000..5a4ed32052c52ce6b0a24f70926440e77637c4b1 |
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+++ b/third_party/sqlite/sqlite-src-3070603/src/vacuum.c |
@@ -0,0 +1,345 @@ |
+/* |
+** 2003 April 6 |
+** |
+** 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 code used to implement the VACUUM command. |
+** |
+** Most of the code in this file may be omitted by defining the |
+** SQLITE_OMIT_VACUUM macro. |
+*/ |
+#include "sqliteInt.h" |
+#include "vdbeInt.h" |
+ |
+#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH) |
+/* |
+** Finalize a prepared statement. If there was an error, store the |
+** text of the error message in *pzErrMsg. Return the result code. |
+*/ |
+static int vacuumFinalize(sqlite3 *db, sqlite3_stmt *pStmt, char **pzErrMsg){ |
+ int rc; |
+ rc = sqlite3VdbeFinalize((Vdbe*)pStmt); |
+ if( rc ){ |
+ sqlite3SetString(pzErrMsg, db, sqlite3_errmsg(db)); |
+ } |
+ return rc; |
+} |
+ |
+/* |
+** Execute zSql on database db. Return an error code. |
+*/ |
+static int execSql(sqlite3 *db, char **pzErrMsg, const char *zSql){ |
+ sqlite3_stmt *pStmt; |
+ VVA_ONLY( int rc; ) |
+ if( !zSql ){ |
+ return SQLITE_NOMEM; |
+ } |
+ if( SQLITE_OK!=sqlite3_prepare(db, zSql, -1, &pStmt, 0) ){ |
+ sqlite3SetString(pzErrMsg, db, sqlite3_errmsg(db)); |
+ return sqlite3_errcode(db); |
+ } |
+ VVA_ONLY( rc = ) sqlite3_step(pStmt); |
+ assert( rc!=SQLITE_ROW ); |
+ return vacuumFinalize(db, pStmt, pzErrMsg); |
+} |
+ |
+/* |
+** Execute zSql on database db. The statement returns exactly |
+** one column. Execute this as SQL on the same database. |
+*/ |
+static int execExecSql(sqlite3 *db, char **pzErrMsg, const char *zSql){ |
+ sqlite3_stmt *pStmt; |
+ int rc; |
+ |
+ rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0); |
+ if( rc!=SQLITE_OK ) return rc; |
+ |
+ while( SQLITE_ROW==sqlite3_step(pStmt) ){ |
+ rc = execSql(db, pzErrMsg, (char*)sqlite3_column_text(pStmt, 0)); |
+ if( rc!=SQLITE_OK ){ |
+ vacuumFinalize(db, pStmt, pzErrMsg); |
+ return rc; |
+ } |
+ } |
+ |
+ return vacuumFinalize(db, pStmt, pzErrMsg); |
+} |
+ |
+/* |
+** The non-standard VACUUM command is used to clean up the database, |
+** collapse free space, etc. It is modelled after the VACUUM command |
+** in PostgreSQL. |
+** |
+** In version 1.0.x of SQLite, the VACUUM command would call |
+** gdbm_reorganize() on all the database tables. But beginning |
+** with 2.0.0, SQLite no longer uses GDBM so this command has |
+** become a no-op. |
+*/ |
+void sqlite3Vacuum(Parse *pParse){ |
+ Vdbe *v = sqlite3GetVdbe(pParse); |
+ if( v ){ |
+ sqlite3VdbeAddOp2(v, OP_Vacuum, 0, 0); |
+ } |
+ return; |
+} |
+ |
+/* |
+** This routine implements the OP_Vacuum opcode of the VDBE. |
+*/ |
+int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){ |
+ int rc = SQLITE_OK; /* Return code from service routines */ |
+ Btree *pMain; /* The database being vacuumed */ |
+ Btree *pTemp; /* The temporary database we vacuum into */ |
+ char *zSql = 0; /* SQL statements */ |
+ int saved_flags; /* Saved value of the db->flags */ |
+ int saved_nChange; /* Saved value of db->nChange */ |
+ int saved_nTotalChange; /* Saved value of db->nTotalChange */ |
+ void (*saved_xTrace)(void*,const char*); /* Saved db->xTrace */ |
+ Db *pDb = 0; /* Database to detach at end of vacuum */ |
+ int isMemDb; /* True if vacuuming a :memory: database */ |
+ int nRes; /* Bytes of reserved space at the end of each page */ |
+ int nDb; /* Number of attached databases */ |
+ |
+ if( !db->autoCommit ){ |
+ sqlite3SetString(pzErrMsg, db, "cannot VACUUM from within a transaction"); |
+ return SQLITE_ERROR; |
+ } |
+ if( db->activeVdbeCnt>1 ){ |
+ sqlite3SetString(pzErrMsg, db,"cannot VACUUM - SQL statements in progress"); |
+ return SQLITE_ERROR; |
+ } |
+ |
+ /* Save the current value of the database flags so that it can be |
+ ** restored before returning. Then set the writable-schema flag, and |
+ ** disable CHECK and foreign key constraints. */ |
+ saved_flags = db->flags; |
+ saved_nChange = db->nChange; |
+ saved_nTotalChange = db->nTotalChange; |
+ saved_xTrace = db->xTrace; |
+ db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks | SQLITE_PreferBuiltin; |
+ db->flags &= ~(SQLITE_ForeignKeys | SQLITE_ReverseOrder); |
+ db->xTrace = 0; |
+ |
+ pMain = db->aDb[0].pBt; |
+ isMemDb = sqlite3PagerIsMemdb(sqlite3BtreePager(pMain)); |
+ |
+ /* Attach the temporary database as 'vacuum_db'. The synchronous pragma |
+ ** can be set to 'off' for this file, as it is not recovered if a crash |
+ ** occurs anyway. The integrity of the database is maintained by a |
+ ** (possibly synchronous) transaction opened on the main database before |
+ ** sqlite3BtreeCopyFile() is called. |
+ ** |
+ ** An optimisation would be to use a non-journaled pager. |
+ ** (Later:) I tried setting "PRAGMA vacuum_db.journal_mode=OFF" but |
+ ** that actually made the VACUUM run slower. Very little journalling |
+ ** actually occurs when doing a vacuum since the vacuum_db is initially |
+ ** empty. Only the journal header is written. Apparently it takes more |
+ ** time to parse and run the PRAGMA to turn journalling off than it does |
+ ** to write the journal header file. |
+ */ |
+ nDb = db->nDb; |
+ if( sqlite3TempInMemory(db) ){ |
+ zSql = "ATTACH ':memory:' AS vacuum_db;"; |
+ }else{ |
+ zSql = "ATTACH '' AS vacuum_db;"; |
+ } |
+ rc = execSql(db, pzErrMsg, zSql); |
+ if( db->nDb>nDb ){ |
+ pDb = &db->aDb[db->nDb-1]; |
+ assert( strcmp(pDb->zName,"vacuum_db")==0 ); |
+ } |
+ if( rc!=SQLITE_OK ) goto end_of_vacuum; |
+ pTemp = db->aDb[db->nDb-1].pBt; |
+ |
+ /* The call to execSql() to attach the temp database has left the file |
+ ** locked (as there was more than one active statement when the transaction |
+ ** to read the schema was concluded. Unlock it here so that this doesn't |
+ ** cause problems for the call to BtreeSetPageSize() below. */ |
+ sqlite3BtreeCommit(pTemp); |
+ |
+ nRes = sqlite3BtreeGetReserve(pMain); |
+ |
+ /* A VACUUM cannot change the pagesize of an encrypted database. */ |
+#ifdef SQLITE_HAS_CODEC |
+ if( db->nextPagesize ){ |
+ extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*); |
+ int nKey; |
+ char *zKey; |
+ sqlite3CodecGetKey(db, 0, (void**)&zKey, &nKey); |
+ if( nKey ) db->nextPagesize = 0; |
+ } |
+#endif |
+ |
+ /* Do not attempt to change the page size for a WAL database */ |
+ if( sqlite3PagerGetJournalMode(sqlite3BtreePager(pMain)) |
+ ==PAGER_JOURNALMODE_WAL ){ |
+ db->nextPagesize = 0; |
+ } |
+ |
+ if( sqlite3BtreeSetPageSize(pTemp, sqlite3BtreeGetPageSize(pMain), nRes, 0) |
+ || (!isMemDb && sqlite3BtreeSetPageSize(pTemp, db->nextPagesize, nRes, 0)) |
+ || NEVER(db->mallocFailed) |
+ ){ |
+ rc = SQLITE_NOMEM; |
+ goto end_of_vacuum; |
+ } |
+ rc = execSql(db, pzErrMsg, "PRAGMA vacuum_db.synchronous=OFF"); |
+ if( rc!=SQLITE_OK ){ |
+ goto end_of_vacuum; |
+ } |
+ |
+#ifndef SQLITE_OMIT_AUTOVACUUM |
+ sqlite3BtreeSetAutoVacuum(pTemp, db->nextAutovac>=0 ? db->nextAutovac : |
+ sqlite3BtreeGetAutoVacuum(pMain)); |
+#endif |
+ |
+ /* Begin a transaction */ |
+ rc = execSql(db, pzErrMsg, "BEGIN EXCLUSIVE;"); |
+ if( rc!=SQLITE_OK ) goto end_of_vacuum; |
+ |
+ /* Query the schema of the main database. Create a mirror schema |
+ ** in the temporary database. |
+ */ |
+ rc = execExecSql(db, pzErrMsg, |
+ "SELECT 'CREATE TABLE vacuum_db.' || substr(sql,14) " |
+ " FROM sqlite_master WHERE type='table' AND name!='sqlite_sequence'" |
+ " AND rootpage>0" |
+ ); |
+ if( rc!=SQLITE_OK ) goto end_of_vacuum; |
+ rc = execExecSql(db, pzErrMsg, |
+ "SELECT 'CREATE INDEX vacuum_db.' || substr(sql,14)" |
+ " FROM sqlite_master WHERE sql LIKE 'CREATE INDEX %' "); |
+ if( rc!=SQLITE_OK ) goto end_of_vacuum; |
+ rc = execExecSql(db, pzErrMsg, |
+ "SELECT 'CREATE UNIQUE INDEX vacuum_db.' || substr(sql,21) " |
+ " FROM sqlite_master WHERE sql LIKE 'CREATE UNIQUE INDEX %'"); |
+ if( rc!=SQLITE_OK ) goto end_of_vacuum; |
+ |
+ /* Loop through the tables in the main database. For each, do |
+ ** an "INSERT INTO vacuum_db.xxx SELECT * FROM main.xxx;" to copy |
+ ** the contents to the temporary database. |
+ */ |
+ rc = execExecSql(db, pzErrMsg, |
+ "SELECT 'INSERT INTO vacuum_db.' || quote(name) " |
+ "|| ' SELECT * FROM main.' || quote(name) || ';'" |
+ "FROM main.sqlite_master " |
+ "WHERE type = 'table' AND name!='sqlite_sequence' " |
+ " AND rootpage>0" |
+ ); |
+ if( rc!=SQLITE_OK ) goto end_of_vacuum; |
+ |
+ /* Copy over the sequence table |
+ */ |
+ rc = execExecSql(db, pzErrMsg, |
+ "SELECT 'DELETE FROM vacuum_db.' || quote(name) || ';' " |
+ "FROM vacuum_db.sqlite_master WHERE name='sqlite_sequence' " |
+ ); |
+ if( rc!=SQLITE_OK ) goto end_of_vacuum; |
+ rc = execExecSql(db, pzErrMsg, |
+ "SELECT 'INSERT INTO vacuum_db.' || quote(name) " |
+ "|| ' SELECT * FROM main.' || quote(name) || ';' " |
+ "FROM vacuum_db.sqlite_master WHERE name=='sqlite_sequence';" |
+ ); |
+ if( rc!=SQLITE_OK ) goto end_of_vacuum; |
+ |
+ |
+ /* Copy the triggers, views, and virtual tables from the main database |
+ ** over to the temporary database. None of these objects has any |
+ ** associated storage, so all we have to do is copy their entries |
+ ** from the SQLITE_MASTER table. |
+ */ |
+ rc = execSql(db, pzErrMsg, |
+ "INSERT INTO vacuum_db.sqlite_master " |
+ " SELECT type, name, tbl_name, rootpage, sql" |
+ " FROM main.sqlite_master" |
+ " WHERE type='view' OR type='trigger'" |
+ " OR (type='table' AND rootpage=0)" |
+ ); |
+ if( rc ) goto end_of_vacuum; |
+ |
+ /* At this point, unless the main db was completely empty, there is now a |
+ ** transaction open on the vacuum database, but not on the main database. |
+ ** Open a btree level transaction on the main database. This allows a |
+ ** call to sqlite3BtreeCopyFile(). The main database btree level |
+ ** transaction is then committed, so the SQL level never knows it was |
+ ** opened for writing. This way, the SQL transaction used to create the |
+ ** temporary database never needs to be committed. |
+ */ |
+ { |
+ u32 meta; |
+ int i; |
+ |
+ /* This array determines which meta meta values are preserved in the |
+ ** vacuum. Even entries are the meta value number and odd entries |
+ ** are an increment to apply to the meta value after the vacuum. |
+ ** The increment is used to increase the schema cookie so that other |
+ ** connections to the same database will know to reread the schema. |
+ */ |
+ static const unsigned char aCopy[] = { |
+ BTREE_SCHEMA_VERSION, 1, /* Add one to the old schema cookie */ |
+ BTREE_DEFAULT_CACHE_SIZE, 0, /* Preserve the default page cache size */ |
+ BTREE_TEXT_ENCODING, 0, /* Preserve the text encoding */ |
+ BTREE_USER_VERSION, 0, /* Preserve the user version */ |
+ }; |
+ |
+ assert( 1==sqlite3BtreeIsInTrans(pTemp) ); |
+ assert( 1==sqlite3BtreeIsInTrans(pMain) ); |
+ |
+ /* Copy Btree meta values */ |
+ for(i=0; i<ArraySize(aCopy); i+=2){ |
+ /* GetMeta() and UpdateMeta() cannot fail in this context because |
+ ** we already have page 1 loaded into cache and marked dirty. */ |
+ sqlite3BtreeGetMeta(pMain, aCopy[i], &meta); |
+ rc = sqlite3BtreeUpdateMeta(pTemp, aCopy[i], meta+aCopy[i+1]); |
+ if( NEVER(rc!=SQLITE_OK) ) goto end_of_vacuum; |
+ } |
+ |
+ rc = sqlite3BtreeCopyFile(pMain, pTemp); |
+ if( rc!=SQLITE_OK ) goto end_of_vacuum; |
+ rc = sqlite3BtreeCommit(pTemp); |
+ if( rc!=SQLITE_OK ) goto end_of_vacuum; |
+#ifndef SQLITE_OMIT_AUTOVACUUM |
+ sqlite3BtreeSetAutoVacuum(pMain, sqlite3BtreeGetAutoVacuum(pTemp)); |
+#endif |
+ } |
+ |
+ assert( rc==SQLITE_OK ); |
+ rc = sqlite3BtreeSetPageSize(pMain, sqlite3BtreeGetPageSize(pTemp), nRes,1); |
+ |
+end_of_vacuum: |
+ /* Restore the original value of db->flags */ |
+ db->flags = saved_flags; |
+ db->nChange = saved_nChange; |
+ db->nTotalChange = saved_nTotalChange; |
+ db->xTrace = saved_xTrace; |
+ sqlite3BtreeSetPageSize(pMain, -1, -1, 1); |
+ |
+ /* Currently there is an SQL level transaction open on the vacuum |
+ ** database. No locks are held on any other files (since the main file |
+ ** was committed at the btree level). So it safe to end the transaction |
+ ** by manually setting the autoCommit flag to true and detaching the |
+ ** vacuum database. The vacuum_db journal file is deleted when the pager |
+ ** is closed by the DETACH. |
+ */ |
+ db->autoCommit = 1; |
+ |
+ if( pDb ){ |
+ sqlite3BtreeClose(pDb->pBt); |
+ pDb->pBt = 0; |
+ pDb->pSchema = 0; |
+ } |
+ |
+ /* This both clears the schemas and reduces the size of the db->aDb[] |
+ ** array. */ |
+ sqlite3ResetInternalSchema(db, -1); |
+ |
+ return rc; |
+} |
+ |
+#endif /* SQLITE_OMIT_VACUUM && SQLITE_OMIT_ATTACH */ |