/*
** An SQL user-function registered to do the work of an DETACH statement. The
** three arguments to the function come directly from a detach statement:
**
** DETACH DATABASE x
**
** SELECT sqlite_detach(x)
*/
static void detachFunc(
sqlite3_context *context,
int NotUsed,
sqlite3_value **argv
){
const char *zName = (const char *)sqlite3_value_text(argv[0]);
sqlite3 *db = sqlite3_context_db_handle(context);
int i;
Db *pDb = 0;
char zErr[128];
UNUSED_PARAMETER(NotUsed);
if( zName==0 ) zName = "";
for(i=0; i<db->nDb; i++){
pDb = &db->aDb[i];
if( pDb->pBt==0 ) continue;
if( sqlite3StrICmp(pDb->zName, zName)==0 ) break;
}
if( i>=db->nDb ){
sqlite3_snprintf(sizeof(zErr),zErr, "no such database: %s", zName);
goto detach_error;
}
if( i<2 ){
sqlite3_snprintf(sizeof(zErr),zErr, "cannot detach database %s", zName);
goto detach_error;
}
if( !db->autoCommit ){
sqlite3_snprintf(sizeof(zErr), zErr,
"cannot DETACH database within transaction");
goto detach_error;
}
if( sqlite3BtreeIsInReadTrans(pDb->pBt) || sqlite3BtreeIsInBackup(pDb->pBt) ){
sqlite3_snprintf(sizeof(zErr),zErr, "database %s is locked", zName);
goto detach_error;
}
sqlite3BtreeClose(pDb->pBt);
pDb->pBt = 0;
pDb->pSchema = 0;
sqlite3ResetAllSchemasOfConnection(db);
return;
detach_error:
sqlite3_result_error(context, zErr, -1);
}
/*
** An SQL user-function registered to do the work of an ATTACH statement. The
** three arguments to the function come directly from an attach statement:
**
** ATTACH DATABASE x AS y KEY z
**
** SELECT sqlite_attach(x, y, z)
**
** If the optional "KEY z" syntax is omitted, an SQL NULL is passed as the
** third argument.
*/
static void attachFunc(
sqlite3_context *context,
int NotUsed,
sqlite3_value **argv
){
int i;
int rc = 0;
sqlite3 *db = sqlite3_context_db_handle(context);
const char *zName;
const char *zFile;
char *zPath = 0;
char *zErr = 0;
unsigned int flags;
Db *aNew;
char *zErrDyn = 0;
sqlite3_vfs *pVfs;
UNUSED_PARAMETER(NotUsed);
zFile = (const char *)sqlite3_value_text(argv[0]);
zName = (const char *)sqlite3_value_text(argv[1]);
if( zFile==0 ) zFile = "";
if( zName==0 ) zName = "";
/* Check for the following errors:
**
** * Too many attached databases,
** * Transaction currently open
** * Specified database name already being used.
*/
if( db->nDb>=db->aLimit[SQLITE_LIMIT_ATTACHED]+2 ){
zErrDyn = sqlite3MPrintf(db, "too many attached databases - max %d",
db->aLimit[SQLITE_LIMIT_ATTACHED]
);
goto attach_error;
}
if( !db->autoCommit ){
zErrDyn = sqlite3MPrintf(db, "cannot ATTACH database within transaction");
goto attach_error;
}
for(i=0; i<db->nDb; i++){
char *z = db->aDb[i].zName;
assert( z && zName );
if( sqlite3StrICmp(z, zName)==0 ){
zErrDyn = sqlite3MPrintf(db, "database %s is already in use", zName);
goto attach_error;
}
}
/* Allocate the new entry in the db->aDb[] array and initialize the schema
** hash tables.
*/
if( db->aDb==db->aDbStatic ){
aNew = sqlite3DbMallocRaw(db, sizeof(db->aDb[0])*3 );
if( aNew==0 ) return;
memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2);
}else{
aNew = sqlite3DbRealloc(db, db->aDb, sizeof(db->aDb[0])*(db->nDb+1) );
if( aNew==0 ) return;
}
db->aDb = aNew;
aNew = &db->aDb[db->nDb];
memset(aNew, 0, sizeof(*aNew));
/* Open the database file. If the btree is successfully opened, use
** it to obtain the database schema. At this point the schema may
** or may not be initialized.
*/
flags = db->openFlags;
rc = sqlite3ParseUri(db->pVfs->zName, zFile, &flags, &pVfs, &zPath, &zErr);
if( rc!=SQLITE_OK ){
if( rc==SQLITE_NOMEM ) db->mallocFailed = 1;
sqlite3_result_error(context, zErr, -1);
sqlite3_free(zErr);
return;
}
assert( pVfs );
flags |= SQLITE_OPEN_MAIN_DB;
rc = sqlite3BtreeOpen(pVfs, zPath, db, &aNew->pBt, 0, flags);
sqlite3_free( zPath );
db->nDb++;
if( rc==SQLITE_CONSTRAINT ){
rc = SQLITE_ERROR;
zErrDyn = sqlite3MPrintf(db, "database is already attached");
}else if( rc==SQLITE_OK ){
Pager *pPager;
aNew->pSchema = sqlite3SchemaGet(db, aNew->pBt);
if( !aNew->pSchema ){
rc = SQLITE_NOMEM;
}else if( aNew->pSchema->file_format && aNew->pSchema->enc!=ENC(db) ){
zErrDyn = sqlite3MPrintf(db,
"attached databases must use the same text encoding as main database");
rc = SQLITE_ERROR;
}
sqlite3BtreeEnter(aNew->pBt);
pPager = sqlite3BtreePager(aNew->pBt);
sqlite3PagerLockingMode(pPager, db->dfltLockMode);
sqlite3BtreeSecureDelete(aNew->pBt,
sqlite3BtreeSecureDelete(db->aDb[0].pBt,-1) );
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
sqlite3BtreeSetPagerFlags(aNew->pBt, 3 | (db->flags & PAGER_FLAGS_MASK));
#endif
sqlite3BtreeLeave(aNew->pBt);
}
aNew->safety_level = 3;
aNew->zName = sqlite3DbStrDup(db, zName);
if( rc==SQLITE_OK && aNew->zName==0 ){
rc = SQLITE_NOMEM;
}
#ifdef SQLITE_HAS_CODEC
if( rc==SQLITE_OK ){
extern int sqlite3CodecAttach(sqlite3*, int, const void*, int);
extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*);
int nKey;
char *zKey;
int t = sqlite3_value_type(argv[2]);
switch( t ){
case SQLITE_INTEGER:
case SQLITE_FLOAT:
zErrDyn = sqlite3DbStrDup(db, "Invalid key value");
rc = SQLITE_ERROR;
break;
case SQLITE_TEXT:
case SQLITE_BLOB:
nKey = sqlite3_value_bytes(argv[2]);
zKey = (char *)sqlite3_value_blob(argv[2]);
rc = sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
break;
case SQLITE_NULL:
/* No key specified. Use the key from the main database */
sqlite3CodecGetKey(db, 0, (void**)&zKey, &nKey);
if( nKey>0 || sqlite3BtreeGetOptimalReserve(db->aDb[0].pBt)>0 ){
rc = sqlite3CodecAttach(db, db->nDb-1, zKey, nKey);
}
break;
}
}
#endif
/* If the file was opened successfully, read the schema for the new database.
** If this fails, or if opening the file failed, then close the file and
** remove the entry from the db->aDb[] array. i.e. put everything back the way
** we found it.
*/
if( rc==SQLITE_OK ){
sqlite3BtreeEnterAll(db);
rc = sqlite3Init(db, &zErrDyn);
sqlite3BtreeLeaveAll(db);
}
#ifdef SQLITE_USER_AUTHENTICATION
if( rc==SQLITE_OK ){
u8 newAuth = 0;
rc = sqlite3UserAuthCheckLogin(db, zName, &newAuth);
if( newAuth<db->auth.authLevel ){
rc = SQLITE_AUTH_USER;
}
}
#endif
if( rc ){
int iDb = db->nDb - 1;
assert( iDb>=2 );
if( db->aDb[iDb].pBt ){
sqlite3BtreeClose(db->aDb[iDb].pBt);
db->aDb[iDb].pBt = 0;
db->aDb[iDb].pSchema = 0;
}
sqlite3ResetAllSchemasOfConnection(db);
db->nDb = iDb;
if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
db->mallocFailed = 1;
sqlite3DbFree(db, zErrDyn);
zErrDyn = sqlite3MPrintf(db, "out of memory");
}else if( zErrDyn==0 ){
zErrDyn = sqlite3MPrintf(db, "unable to open database: %s", zFile);
}
goto attach_error;
}
return;
attach_error:
/* Return an error if we get here */
if( zErrDyn ){
sqlite3_result_error(context, zErrDyn, -1);
sqlite3DbFree(db, zErrDyn);
}
if( rc ) sqlite3_result_error_code(context, rc);
}
/* CHANGE 1 of 3: Add function parameter nRes */
SQLITE_PRIVATE int sqlite3RunVacuumForRekey(char **pzErrMsg, sqlite3 *db, int iDb, int nRes){
int rc = SQLITE_OK; /* Return code from service routines */
Btree *pMain; /* The database being vacuumed */
Btree *pTemp; /* The temporary database we vacuum into */
u16 saved_mDbFlags; /* Saved value of db->mDbFlags */
u32 saved_flags; /* Saved value of db->flags */
int saved_nChange; /* Saved value of db->nChange */
int saved_nTotalChange; /* Saved value of db->nTotalChange */
u8 saved_mTrace; /* Saved trace settings */
Db *pDb = 0; /* Database to detach at end of vacuum */
int isMemDb; /* True if vacuuming a :memory: database */
/* CHANGE 2 of 3: Do not define local variable nRes */
/*int nRes;*/ /* Bytes of reserved space at the end of each page */
int nDb; /* Number of attached databases */
const char *zDbMain; /* Schema name of database to vacuum */
if (!db->autoCommit) {
sqlite3SetString(pzErrMsg, db, "cannot VACUUM from within a transaction");
return SQLITE_ERROR;
}
if (db->nVdbeActive>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_mDbFlags = db->mDbFlags;
saved_nChange = db->nChange;
saved_nTotalChange = db->nTotalChange;
saved_mTrace = db->mTrace;
db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks;
db->mDbFlags |= DBFLAG_PreferBuiltin | DBFLAG_Vacuum;
db->flags &= ~(SQLITE_ForeignKeys | SQLITE_ReverseOrder | SQLITE_CountRows);
db->mTrace = 0;
zDbMain = db->aDb[iDb].zDbSName;
pMain = db->aDb[iDb].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;
rc = execSql(db, pzErrMsg, "ATTACH''AS vacuum_db");
if (rc != SQLITE_OK) goto end_of_vacuum;
assert((db->nDb - 1) == nDb);
pDb = &db->aDb[nDb];
assert(strcmp(pDb->zDbSName, "vacuum_db") == 0);
pTemp = pDb->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);
/* CHANGE 3 of 3: Do not call sqlite3BtreeGetOptimalReserve */
/* nRes = sqlite3BtreeGetOptimalReserve(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, iDb, (void**)&zKey, &nKey);
if (nKey) db->nextPagesize = 0;
}
#endif
sqlite3BtreeSetCacheSize(pTemp, db->aDb[iDb].pSchema->cache_size);
sqlite3BtreeSetSpillSize(pTemp, sqlite3BtreeSetSpillSize(pMain, 0));
sqlite3BtreeSetPagerFlags(pTemp, PAGER_SYNCHRONOUS_OFF | PAGER_CACHESPILL);
/* Begin a transaction and take an exclusive lock on the main database
** file. This is done before the sqlite3BtreeGetPageSize(pMain) call below,
** to ensure that we do not try to change the page-size on a WAL database.
*/
rc = execSql(db, pzErrMsg, "BEGIN");
if (rc != SQLITE_OK) goto end_of_vacuum;
rc = sqlite3BtreeBeginTrans(pMain, 2);
if (rc != SQLITE_OK) goto end_of_vacuum;
/* 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_BKPT;
goto end_of_vacuum;
}
#ifndef SQLITE_OMIT_AUTOVACUUM
sqlite3BtreeSetAutoVacuum(pTemp, db->nextAutovac >= 0 ? db->nextAutovac :
sqlite3BtreeGetAutoVacuum(pMain));
#endif
/* Query the schema of the main database. Create a mirror schema
** in the temporary database.
*/
db->init.iDb = nDb; /* force new CREATE statements into vacuum_db */
rc = execSqlF(db, pzErrMsg,
"SELECT sql FROM \"%w\".sqlite_master"
" WHERE type='table'AND name<>'sqlite_sequence'"
" AND coalesce(rootpage,1)>0",
zDbMain
);
if (rc != SQLITE_OK) goto end_of_vacuum;
rc = execSqlF(db, pzErrMsg,
"SELECT sql FROM \"%w\".sqlite_master"
" WHERE type='index'",
zDbMain
);
if (rc != SQLITE_OK) goto end_of_vacuum;
db->init.iDb = 0;
/* 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 = execSqlF(db, pzErrMsg,
"SELECT'INSERT INTO vacuum_db.'||quote(name)"
"||' SELECT*FROM\"%w\".'||quote(name)"
"FROM vacuum_db.sqlite_master "
"WHERE type='table'AND coalesce(rootpage,1)>0",
zDbMain
);
assert((db->mDbFlags & DBFLAG_Vacuum) != 0);
db->mDbFlags &= ~DBFLAG_Vacuum;
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 = execSqlF(db, pzErrMsg,
"INSERT INTO vacuum_db.sqlite_master"
" SELECT*FROM \"%w\".sqlite_master"
" WHERE type IN('view','trigger')"
" OR(type='table'AND rootpage=0)",
zDbMain
);
if (rc) goto end_of_vacuum;
/* At this point, there is a write transaction open on both the
** vacuum database and the main database. Assuming no error occurs,
** both transactions are closed by this block - the main database
** transaction by sqlite3BtreeCopyFile() and the other by an explicit
** call to sqlite3BtreeCommit().
*/
{
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 */
BTREE_APPLICATION_ID, 0, /* Preserve the application id */
};
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->init.iDb = 0;
db->mDbFlags = saved_mDbFlags;
db->flags = saved_flags;
db->nChange = saved_nChange;
db->nTotalChange = saved_nTotalChange;
db->mTrace = saved_mTrace;
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. */
sqlite3ResetAllSchemasOfConnection(db);
return rc;
}
/*
** Copy nPage pages from the source b-tree to the destination.
*/
int sqlite3_backup_step(sqlite3_backup *p, int nPage){
int rc;
int destMode; /* Destination journal mode */
int pgszSrc = 0; /* Source page size */
int pgszDest = 0; /* Destination page size */
#ifdef SQLITE_ENABLE_API_ARMOR
if( p==0 ) return SQLITE_MISUSE_BKPT;
#endif
sqlite3_mutex_enter(p->pSrcDb->mutex);
sqlite3BtreeEnter(p->pSrc);
if( p->pDestDb ){
sqlite3_mutex_enter(p->pDestDb->mutex);
}
rc = p->rc;
if( !isFatalError(rc) ){
Pager * const pSrcPager = sqlite3BtreePager(p->pSrc); /* Source pager */
Pager * const pDestPager = sqlite3BtreePager(p->pDest); /* Dest pager */
int ii; /* Iterator variable */
int nSrcPage = -1; /* Size of source db in pages */
int bCloseTrans = 0; /* True if src db requires unlocking */
/* If the source pager is currently in a write-transaction, return
** SQLITE_BUSY immediately.
*/
if( p->pDestDb && p->pSrc->pBt->inTransaction==TRANS_WRITE ){
rc = SQLITE_BUSY;
}else{
rc = SQLITE_OK;
}
/* If there is no open read-transaction on the source database, open
** one now. If a transaction is opened here, then it will be closed
** before this function exits.
*/
if( rc==SQLITE_OK && 0==sqlite3BtreeIsInReadTrans(p->pSrc) ){
rc = sqlite3BtreeBeginTrans(p->pSrc, 0, 0);
bCloseTrans = 1;
}
/* If the destination database has not yet been locked (i.e. if this
** is the first call to backup_step() for the current backup operation),
** try to set its page size to the same as the source database. This
** is especially important on ZipVFS systems, as in that case it is
** not possible to create a database file that uses one page size by
** writing to it with another. */
if( p->bDestLocked==0 && rc==SQLITE_OK && setDestPgsz(p)==SQLITE_NOMEM ){
rc = SQLITE_NOMEM;
}
/* Lock the destination database, if it is not locked already. */
if( SQLITE_OK==rc && p->bDestLocked==0
&& SQLITE_OK==(rc = sqlite3BtreeBeginTrans(p->pDest, 2,
(int*)&p->iDestSchema))
){
p->bDestLocked = 1;
}
/* Do not allow backup if the destination database is in WAL mode
** and the page sizes are different between source and destination */
pgszSrc = sqlite3BtreeGetPageSize(p->pSrc);
pgszDest = sqlite3BtreeGetPageSize(p->pDest);
destMode = sqlite3PagerGetJournalMode(sqlite3BtreePager(p->pDest));
if( SQLITE_OK==rc && destMode==PAGER_JOURNALMODE_WAL && pgszSrc!=pgszDest ){
rc = SQLITE_READONLY;
}
/* Now that there is a read-lock on the source database, query the
** source pager for the number of pages in the database.
*/
nSrcPage = (int)sqlite3BtreeLastPage(p->pSrc);
assert( nSrcPage>=0 );
for(ii=0; (nPage<0 || ii<nPage) && p->iNext<=(Pgno)nSrcPage && !rc; ii++){
const Pgno iSrcPg = p->iNext; /* Source page number */
if( iSrcPg!=PENDING_BYTE_PAGE(p->pSrc->pBt) ){
DbPage *pSrcPg; /* Source page object */
rc = sqlite3PagerGet(pSrcPager, iSrcPg, &pSrcPg,PAGER_GET_READONLY);
if( rc==SQLITE_OK ){
rc = backupOnePage(p, iSrcPg, sqlite3PagerGetData(pSrcPg), 0);
sqlite3PagerUnref(pSrcPg);
}
}
p->iNext++;
}
if( rc==SQLITE_OK ){
p->nPagecount = nSrcPage;
p->nRemaining = nSrcPage+1-p->iNext;
if( p->iNext>(Pgno)nSrcPage ){
rc = SQLITE_DONE;
}else if( !p->isAttached ){
attachBackupObject(p);
}
}
/* Update the schema version field in the destination database. This
** is to make sure that the schema-version really does change in
** the case where the source and destination databases have the
** same schema version.
*/
if( rc==SQLITE_DONE ){
if( nSrcPage==0 ){
rc = sqlite3BtreeNewDb(p->pDest);
nSrcPage = 1;
}
if( rc==SQLITE_OK || rc==SQLITE_DONE ){
rc = sqlite3BtreeUpdateMeta(p->pDest,1,p->iDestSchema+1);
}
if( rc==SQLITE_OK ){
if( p->pDestDb ){
sqlite3ResetAllSchemasOfConnection(p->pDestDb);
}
if( destMode==PAGER_JOURNALMODE_WAL ){
rc = sqlite3BtreeSetVersion(p->pDest, 2);
}
}
if( rc==SQLITE_OK ){
int nDestTruncate;
/* Set nDestTruncate to the final number of pages in the destination
** database. The complication here is that the destination page
** size may be different to the source page size.
**
** If the source page size is smaller than the destination page size,
** round up. In this case the call to sqlite3OsTruncate() below will
** fix the size of the file. However it is important to call
** sqlite3PagerTruncateImage() here so that any pages in the
** destination file that lie beyond the nDestTruncate page mark are
** journalled by PagerCommitPhaseOne() before they are destroyed
** by the file truncation.
*/
assert( pgszSrc==sqlite3BtreeGetPageSize(p->pSrc) );
assert( pgszDest==sqlite3BtreeGetPageSize(p->pDest) );
if( pgszSrc<pgszDest ){
int ratio = pgszDest/pgszSrc;
nDestTruncate = (nSrcPage+ratio-1)/ratio;
if( nDestTruncate==(int)PENDING_BYTE_PAGE(p->pDest->pBt) ){
nDestTruncate--;
}
}else{
nDestTruncate = nSrcPage * (pgszSrc/pgszDest);
}
assert( nDestTruncate>0 );
if( pgszSrc<pgszDest ){
/* If the source page-size is smaller than the destination page-size,
** two extra things may need to happen:
**
** * The destination may need to be truncated, and
**
** * Data stored on the pages immediately following the
** pending-byte page in the source database may need to be
** copied into the destination database.
*/
const i64 iSize = (i64)pgszSrc * (i64)nSrcPage;
sqlite3_file * const pFile = sqlite3PagerFile(pDestPager);
Pgno iPg;
int nDstPage;
i64 iOff;
i64 iEnd;
assert( pFile );
assert( nDestTruncate==0
|| (i64)nDestTruncate*(i64)pgszDest >= iSize || (
nDestTruncate==(int)(PENDING_BYTE_PAGE(p->pDest->pBt)-1)
&& iSize>=PENDING_BYTE && iSize<=PENDING_BYTE+pgszDest
));
/* This block ensures that all data required to recreate the original
** database has been stored in the journal for pDestPager and the
** journal synced to disk. So at this point we may safely modify
** the database file in any way, knowing that if a power failure
** occurs, the original database will be reconstructed from the
** journal file. */
sqlite3PagerPagecount(pDestPager, &nDstPage);
for(iPg=nDestTruncate; rc==SQLITE_OK && iPg<=(Pgno)nDstPage; iPg++){
if( iPg!=PENDING_BYTE_PAGE(p->pDest->pBt) ){
DbPage *pPg;
rc = sqlite3PagerGet(pDestPager, iPg, &pPg, 0);
if( rc==SQLITE_OK ){
rc = sqlite3PagerWrite(pPg);
sqlite3PagerUnref(pPg);
}
}
}
if( rc==SQLITE_OK ){
rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 1);
}
/* Write the extra pages and truncate the database file as required */
iEnd = MIN(PENDING_BYTE + pgszDest, iSize);
for(
iOff=PENDING_BYTE+pgszSrc;
rc==SQLITE_OK && iOff<iEnd;
iOff+=pgszSrc
){
PgHdr *pSrcPg = 0;
const Pgno iSrcPg = (Pgno)((iOff/pgszSrc)+1);
rc = sqlite3PagerGet(pSrcPager, iSrcPg, &pSrcPg, 0);
if( rc==SQLITE_OK ){
u8 *zData = sqlite3PagerGetData(pSrcPg);
rc = sqlite3OsWrite(pFile, zData, pgszSrc, iOff);
}
sqlite3PagerUnref(pSrcPg);
}
if( rc==SQLITE_OK ){
rc = backupTruncateFile(pFile, iSize);
}
/* Sync the database file to disk. */
if( rc==SQLITE_OK ){
rc = sqlite3PagerSync(pDestPager, 0);
}
}else{
sqlite3PagerTruncateImage(pDestPager, nDestTruncate);
rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 0);
}
/* Finish committing the transaction to the destination database. */
if( SQLITE_OK==rc
&& SQLITE_OK==(rc = sqlite3BtreeCommitPhaseTwo(p->pDest, 0))
){
rc = SQLITE_DONE;
}
}
}
/* If bCloseTrans is true, then this function opened a read transaction
** on the source database. Close the read transaction here. There is
** no need to check the return values of the btree methods here, as
** "committing" a read-only transaction cannot fail.
*/
if( bCloseTrans ){
TESTONLY( int rc2 );
TESTONLY( rc2 = ) sqlite3BtreeCommitPhaseOne(p->pSrc, 0);
TESTONLY( rc2 |= ) sqlite3BtreeCommitPhaseTwo(p->pSrc, 0);
assert( rc2==SQLITE_OK );
}
if( rc==SQLITE_IOERR_NOMEM ){
rc = SQLITE_NOMEM_BKPT;
}
p->rc = rc;
}
int sqlcipher_codec_ctx_migrate(codec_ctx *ctx) {
u32 meta;
int rc = 0;
int command_idx = 0;
int password_sz;
int saved_flags;
int saved_nChange;
int saved_nTotalChange;
void (*saved_xTrace)(void*,const char*);
Db *pDb = 0;
sqlite3 *db = ctx->pBt->db;
const char *db_filename = sqlite3_db_filename(db, "main");
char *migrated_db_filename = sqlite3_mprintf("%s-migrated", db_filename);
char *pragma_hmac_off = "PRAGMA cipher_use_hmac = OFF;";
char *pragma_4k_kdf_iter = "PRAGMA kdf_iter = 4000;";
char *pragma_1x_and_4k;
char *set_user_version;
char *key;
int key_sz;
int user_version = 0;
int upgrade_1x_format = 0;
int upgrade_4k_format = 0;
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 */
BTREE_APPLICATION_ID, 0, /* Preserve the application id */
};
key_sz = ctx->read_ctx->pass_sz + 1;
key = sqlcipher_malloc(key_sz);
memset(key, 0, key_sz);
memcpy(key, ctx->read_ctx->pass, ctx->read_ctx->pass_sz);
if(db_filename){
const char* commands[5];
char *attach_command = sqlite3_mprintf("ATTACH DATABASE '%s-migrated' as migrate KEY '%q';",
db_filename, key);
int rc = sqlcipher_check_connection(db_filename, key, ctx->read_ctx->pass_sz, "", &user_version);
if(rc == SQLITE_OK){
CODEC_TRACE(("No upgrade required - exiting\n"));
goto exit;
}
// Version 2 - check for 4k with hmac format
rc = sqlcipher_check_connection(db_filename, key, ctx->read_ctx->pass_sz, pragma_4k_kdf_iter, &user_version);
if(rc == SQLITE_OK) {
CODEC_TRACE(("Version 2 format found\n"));
upgrade_4k_format = 1;
}
// Version 1 - check both no hmac and 4k together
pragma_1x_and_4k = sqlite3_mprintf("%s%s", pragma_hmac_off,
pragma_4k_kdf_iter);
rc = sqlcipher_check_connection(db_filename, key, ctx->read_ctx->pass_sz, pragma_1x_and_4k, &user_version);
sqlite3_free(pragma_1x_and_4k);
if(rc == SQLITE_OK) {
CODEC_TRACE(("Version 1 format found\n"));
upgrade_1x_format = 1;
upgrade_4k_format = 1;
}
if(upgrade_1x_format == 0 && upgrade_4k_format == 0) {
CODEC_TRACE(("Upgrade format not determined\n"));
goto handle_error;
}
set_user_version = sqlite3_mprintf("PRAGMA migrate.user_version = %d;", user_version);
commands[0] = upgrade_4k_format == 1 ? pragma_4k_kdf_iter : "";
commands[1] = upgrade_1x_format == 1 ? pragma_hmac_off : "";
commands[2] = attach_command;
commands[3] = "SELECT sqlcipher_export('migrate');";
commands[4] = set_user_version;
for(command_idx = 0; command_idx < ArraySize(commands); command_idx++){
const char *command = commands[command_idx];
if(strcmp(command, "") == 0){
continue;
}
rc = sqlite3_exec(db, command, NULL, NULL, NULL);
if(rc != SQLITE_OK){
break;
}
}
sqlite3_free(attach_command);
sqlite3_free(set_user_version);
sqlcipher_free(key, key_sz);
if(rc == SQLITE_OK){
Btree *pDest;
Btree *pSrc;
int i = 0;
if( !db->autoCommit ){
CODEC_TRACE(("cannot migrate from within a transaction"));
goto handle_error;
}
if( db->nVdbeActive>1 ){
CODEC_TRACE(("cannot migrate - SQL statements in progress"));
goto handle_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;
pDest = db->aDb[0].pBt;
pDb = &(db->aDb[db->nDb-1]);
pSrc = pDb->pBt;
rc = sqlite3_exec(db, "BEGIN;", NULL, NULL, NULL);
rc = sqlite3BtreeBeginTrans(pSrc, 2);
rc = sqlite3BtreeBeginTrans(pDest, 2);
assert( 1==sqlite3BtreeIsInTrans(pDest) );
assert( 1==sqlite3BtreeIsInTrans(pSrc) );
sqlite3CodecGetKey(db, db->nDb - 1, (void**)&key, &password_sz);
sqlite3CodecAttach(db, 0, key, password_sz);
sqlite3pager_get_codec(pDest->pBt->pPager, (void**)&ctx);
ctx->skip_read_hmac = 1;
for(i=0; i<ArraySize(aCopy); i+=2){
sqlite3BtreeGetMeta(pSrc, aCopy[i], &meta);
rc = sqlite3BtreeUpdateMeta(pDest, aCopy[i], meta+aCopy[i+1]);
if( NEVER(rc!=SQLITE_OK) ) goto handle_error;
}
rc = sqlite3BtreeCopyFile(pDest, pSrc);
ctx->skip_read_hmac = 0;
if( rc!=SQLITE_OK ) goto handle_error;
rc = sqlite3BtreeCommit(pDest);
db->flags = saved_flags;
db->nChange = saved_nChange;
db->nTotalChange = saved_nTotalChange;
db->xTrace = saved_xTrace;
db->autoCommit = 1;
if( pDb ){
sqlite3BtreeClose(pDb->pBt);
pDb->pBt = 0;
pDb->pSchema = 0;
}
sqlite3ResetAllSchemasOfConnection(db);
remove(migrated_db_filename);
sqlite3_free(migrated_db_filename);
} else {
CODEC_TRACE(("*** migration failure** \n\n"));
}
}
goto exit;
handle_error:
CODEC_TRACE(("An error occurred attempting to migrate the database\n"));
rc = SQLITE_ERROR;
exit:
return rc;
}
