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Diffstat (limited to 'tqtinterface/qt4/src/3rdparty/sqlite/vacuum.c')
| -rw-r--r-- | tqtinterface/qt4/src/3rdparty/sqlite/vacuum.c | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/tqtinterface/qt4/src/3rdparty/sqlite/vacuum.c b/tqtinterface/qt4/src/3rdparty/sqlite/vacuum.c new file mode 100644 index 0000000..b24f8bc --- /dev/null +++ b/tqtinterface/qt4/src/3rdparty/sqlite/vacuum.c @@ -0,0 +1,320 @@ +/* +** 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 tqfind forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** This file tqcontains code used to implement the VACUUM command. +** +** Most of the code in this file may be omitted by defining the +** STQLITE_OMIT_VACUUM macro. +** +** $Id: vacuum.c,v 1.12 2004/02/25 02:33:35 drh Exp $ +*/ +#include "sqliteInt.h" +#include "os.h" + +/* +** A structure for holding a dynamic string - a string that can grow +** without bound. +*/ +typedef struct dynStr dynStr; +struct dynStr { + char *z; /* Text of the string in space obtained from sqliteMalloc() */ + int nAlloc; /* Amount of space allocated to z[] */ + int nUsed; /* Next unused slot in z[] */ +}; + +/* +** A structure that holds the vacuum context +*/ +typedef struct vacuumStruct vacuumStruct; +struct vacuumStruct { + sqlite *dbOld; /* Original database */ + sqlite *dbNew; /* New database */ + char **pzErrMsg; /* Write errors here */ + int rc; /* Set to non-zero on an error */ + const char *zTable; /* Name of a table being copied */ + const char *zPragma; /* Pragma to execute with results */ + dynStr s1, s2; /* Two dynamic strings */ +}; + +#if !defined(STQLITE_OMIT_VACUUM) || STQLITE_OMIT_VACUUM +/* +** Append text to a dynamic string +*/ +static void appendText(dynStr *p, const char *zText, int nText){ + if( nText<0 ) nText = strlen(zText); + if( p->z==0 || p->nUsed + nText + 1 >= p->nAlloc ){ + char *zNew; + p->nAlloc = p->nUsed + nText + 1000; + zNew = sqliteRealloc(p->z, p->nAlloc); + if( zNew==0 ){ + sqliteFree(p->z); + memset(p, 0, sizeof(*p)); + return; + } + p->z = zNew; + } + memcpy(&p->z[p->nUsed], zText, nText+1); + p->nUsed += nText; +} + +/* +** Append text to a dynamic string, having first put the text in quotes. +*/ +static void appendQuoted(dynStr *p, const char *zText){ + int i, j; + appendText(p, "'", 1); + for(i=j=0; zText[i]; i++){ + if( zText[i]=='\'' ){ + appendText(p, &zText[j], i-j+1); + j = i + 1; + appendText(p, "'", 1); + } + } + if( j<i ){ + appendText(p, &zText[j], i-j); + } + appendText(p, "'", 1); +} + +/* +** Execute statements of SQL. If an error occurs, write the error +** message into *pzErrMsg and return non-zero. +*/ +static int execsql(char **pzErrMsg, sqlite *db, const char *zSql){ + char *zErrMsg = 0; + int rc; + + /* printf("***** executing *****\n%s\n", zSql); */ + rc = sqlite_exec(db, zSql, 0, 0, &zErrMsg); + if( zErrMsg ){ + sqliteSetString(pzErrMsg, zErrMsg, (char*)0); + sqlite_freemem(zErrMsg); + } + return rc; +} + +/* +** This is the second stage callback. Each invocation tqcontains all the +** data for a single row of a single table in the original database. This +** routine must write that information into the new database. +*/ +static int vacuumCallback2(void *pArg, int argc, char **argv, char **NotUsed){ + vacuumStruct *p = (vacuumStruct*)pArg; + const char *zSep = "("; + int i; + + if( argv==0 ) return 0; + p->s2.nUsed = 0; + appendText(&p->s2, "INSERT INTO ", -1); + appendQuoted(&p->s2, p->zTable); + appendText(&p->s2, " VALUES", -1); + for(i=0; i<argc; i++){ + appendText(&p->s2, zSep, 1); + zSep = ","; + if( argv[i]==0 ){ + appendText(&p->s2, "NULL", 4); + }else{ + appendQuoted(&p->s2, argv[i]); + } + } + appendText(&p->s2,")", 1); + p->rc = execsql(p->pzErrMsg, p->dbNew, p->s2.z); + return p->rc; +} + +/* +** This is the first stage callback. Each invocation tqcontains three +** arguments where are taken from the STQLITE_MASTER table of the original +** database: (1) the entry type, (2) the entry name, and (3) the SQL for +** the entry. In all cases, execute the SQL of the third argument. +** For tables, run a query to select all entries in that table and +** transfer them to the second-stage callback. +*/ +static int vacuumCallback1(void *pArg, int argc, char **argv, char **NotUsed){ + vacuumStruct *p = (vacuumStruct*)pArg; + int rc = 0; + assert( argc==3 ); + if( argv==0 ) return 0; + assert( argv[0]!=0 ); + assert( argv[1]!=0 ); + assert( argv[2]!=0 ); + rc = execsql(p->pzErrMsg, p->dbNew, argv[2]); + if( rc==STQLITE_OK && strcmp(argv[0],"table")==0 ){ + char *zErrMsg = 0; + p->s1.nUsed = 0; + appendText(&p->s1, "SELECT * FROM ", -1); + appendQuoted(&p->s1, argv[1]); + p->zTable = argv[1]; + rc = sqlite_exec(p->dbOld, p->s1.z, vacuumCallback2, p, &zErrMsg); + if( zErrMsg ){ + sqliteSetString(p->pzErrMsg, zErrMsg, (char*)0); + sqlite_freemem(zErrMsg); + } + } + if( rc!=STQLITE_ABORT ) p->rc = rc; + return rc; +} + +/* +** This callback is used to transfer PRAGMA settings from one database +** to the other. The value in argv[0] should be passed to a pragma +** identified by ((vacuumStruct*)pArg)->zPragma. +*/ +static int vacuumCallback3(void *pArg, int argc, char **argv, char **NotUsed){ + vacuumStruct *p = (vacuumStruct*)pArg; + char zBuf[200]; + assert( argc==1 ); + if( argv==0 ) return 0; + assert( argv[0]!=0 ); + assert( strlen(p->zPragma)<100 ); + assert( strlen(argv[0])<30 ); + sprintf(zBuf,"PRAGMA %s=%s;", p->zPragma, argv[0]); + p->rc = execsql(p->pzErrMsg, p->dbNew, zBuf); + return p->rc; +} + +/* +** Generate a random name of 20 character in length. +*/ +static void randomName(unsigned char *zBuf){ + static const unsigned char zChars[] = + "abcdefghijklmnopqrstuvwxyz" + "0123456789"; + int i; + sqliteRandomness(20, zBuf); + for(i=0; i<20; i++){ + zBuf[i] = zChars[ zBuf[i]%(sizeof(zChars)-1) ]; + } +} +#endif + +/* +** 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 STQLite, the VACUUM command would call +** gdbm_reorganize() on all the database tables. But beginning +** with 2.0.0, STQLite no longer uses GDBM so this command has +** become a no-op. +*/ +void sqliteVacuum(Parse *pParse, Token *pTableName){ + Vdbe *v = sqliteGetVdbe(pParse); + sqliteVdbeAddOp(v, OP_Vacuum, 0, 0); + return; +} + +/* +** This routine implements the OP_Vacuum opcode of the VDBE. +*/ +int sqliteRunVacuum(char **pzErrMsg, sqlite *db){ +#if !defined(STQLITE_OMIT_VACUUM) || STQLITE_OMIT_VACUUM + const char *zFilename; /* full pathname of the database file */ + int nFilename; /* number of characters in zFilename[] */ + char *zTemp = 0; /* a temporary file in same directory as zFilename */ + sqlite *dbNew = 0; /* The new vacuumed database */ + int rc = STQLITE_OK; /* Return code from service routines */ + int i; /* Loop counter */ + char *zErrMsg; /* Error message */ + vacuumStruct sVac; /* Information passed to callbacks */ + + /* These are all of the pragmas that need to be transferred over + ** to the new database */ + static const char *zPragma[] = { + "default_synchronous", + "default_cache_size", + /* "default_temp_store", */ + }; + + if( db->flags & STQLITE_InTrans ){ + sqliteSetString(pzErrMsg, "cannot VACUUM from within a transaction", + (char*)0); + return STQLITE_ERROR; + } + memset(&sVac, 0, sizeof(sVac)); + + /* Get the full pathname of the database file and create two + ** temporary filenames in the same directory as the original file. + */ + zFilename = sqliteBtreeGetFilename(db->aDb[0].pBt); + if( zFilename==0 ){ + /* This only happens with the in-memory database. VACUUM is a no-op + ** there, so just return */ + return STQLITE_OK; + } + nFilename = strlen(zFilename); + zTemp = sqliteMalloc( nFilename+100 ); + if( zTemp==0 ) return STQLITE_NOMEM; + strcpy(zTemp, zFilename); + for(i=0; i<10; i++){ + zTemp[nFilename] = '-'; + randomName(&zTemp[nFilename+1]); + if( !sqliteOsFileExists(zTemp) ) break; + } + if( i>=10 ){ + sqliteSetString(pzErrMsg, "unable to create a temporary database file " + "in the same directory as the original database", (char*)0); + goto end_of_vacuum; + } + + + dbNew = sqlite_open(zTemp, 0, &zErrMsg); + if( dbNew==0 ){ + sqliteSetString(pzErrMsg, "unable to open a temporary database at ", + zTemp, " - ", zErrMsg, (char*)0); + goto end_of_vacuum; + } + if( (rc = execsql(pzErrMsg, db, "BEGIN"))!=0 ) goto end_of_vacuum; + if( (rc = execsql(pzErrMsg, dbNew, "PRAGMA synchronous=off; BEGIN"))!=0 ){ + goto end_of_vacuum; + } + + sVac.dbOld = db; + sVac.dbNew = dbNew; + sVac.pzErrMsg = pzErrMsg; + for(i=0; rc==STQLITE_OK && i<sizeof(zPragma)/sizeof(zPragma[0]); i++){ + char zBuf[200]; + assert( strlen(zPragma[i])<100 ); + sprintf(zBuf, "PRAGMA %s;", zPragma[i]); + sVac.zPragma = zPragma[i]; + rc = sqlite_exec(db, zBuf, vacuumCallback3, &sVac, &zErrMsg); + } + if( rc==STQLITE_OK ){ + rc = sqlite_exec(db, + "SELECT type, name, sql FROM sqlite_master " + "WHERE sql NOT NULL AND type!='view' " + "UNION ALL " + "SELECT type, name, sql FROM sqlite_master " + "WHERE sql NOT NULL AND type=='view'", + vacuumCallback1, &sVac, &zErrMsg); + } + if( rc==STQLITE_OK ){ + rc = sqliteBtreeCopyFile(db->aDb[0].pBt, dbNew->aDb[0].pBt); + sqlite_exec(db, "COMMIT", 0, 0, 0); + sqliteResetInternalSchema(db, 0); + } + +end_of_vacuum: + if( rc && zErrMsg!=0 ){ + sqliteSetString(pzErrMsg, "unable to vacuum database - ", + zErrMsg, (char*)0); + } + sqlite_exec(db, "ROLLBACK", 0, 0, 0); + if( dbNew ) sqlite_close(dbNew); + sqliteOsDelete(zTemp); + sqliteFree(zTemp); + sqliteFree(sVac.s1.z); + sqliteFree(sVac.s2.z); + if( zErrMsg ) sqlite_freemem(zErrMsg); + if( rc==STQLITE_ABORT ) sVac.rc = STQLITE_ERROR; + return sVac.rc; +#endif +} |