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-rw-r--r--src/attach.c4
-rw-r--r--src/backup.c559
-rw-r--r--src/btree.c227
-rw-r--r--src/btree.h3
-rw-r--r--src/btreeInt.h3
-rw-r--r--src/build.c38
-rw-r--r--src/main.c12
-rw-r--r--src/pager.c32
-rw-r--r--src/pager.h5
-rw-r--r--src/sqlite.h.in174
-rw-r--r--src/sqliteInt.h6
-rw-r--r--src/tclsqlite.c4
-rw-r--r--src/test1.c4
-rw-r--r--src/test_backup.c148
-rw-r--r--src/vacuum.c3
-rw-r--r--src/vdbeaux.c4
16 files changed, 972 insertions, 254 deletions
diff --git a/src/attach.c b/src/attach.c
index 2a7525ae9..bf2683fb3 100644
--- a/src/attach.c
+++ b/src/attach.c
@@ -11,7 +11,7 @@
*************************************************************************
** This file contains code used to implement the ATTACH and DETACH commands.
**
-** $Id: attach.c,v 1.81 2008/12/10 16:45:51 drh Exp $
+** $Id: attach.c,v 1.82 2009/02/03 16:51:25 danielk1977 Exp $
*/
#include "sqliteInt.h"
@@ -265,7 +265,7 @@ static void detachFunc(
"cannot DETACH database within transaction");
goto detach_error;
}
- if( sqlite3BtreeIsInReadTrans(pDb->pBt) ){
+ if( sqlite3BtreeIsInReadTrans(pDb->pBt) || sqlite3BtreeIsInBackup(pDb->pBt) ){
sqlite3_snprintf(sizeof(zErr),zErr, "database %s is locked", zName);
goto detach_error;
}
diff --git a/src/backup.c b/src/backup.c
new file mode 100644
index 000000000..a03ac2ad5
--- /dev/null
+++ b/src/backup.c
@@ -0,0 +1,559 @@
+/*
+** 2009 January 28
+**
+** 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 the implementation of the sqlite3_backup_XXX()
+** API functions and the related features.
+**
+** $Id: backup.c,v 1.1 2009/02/03 16:51:25 danielk1977 Exp $
+*/
+#include "sqliteInt.h"
+#include "btreeInt.h"
+
+/* Macro to find the minimum of two numeric values.
+*/
+#ifndef MIN
+# define MIN(x,y) ((x)<(y)?(x):(y))
+#endif
+
+/*
+** Structure allocated for each backup operation.
+*/
+struct sqlite3_backup {
+ sqlite3* pDestDb; /* Destination database handle */
+ Btree *pDest; /* Destination b-tree file */
+ u32 iDestSchema; /* Original schema cookie in destination */
+ int bDestLocked; /* True once a write-transaction is open on pDest */
+
+ Pgno iNext; /* Page number of the next source page to copy */
+ sqlite3* pSrcDb; /* Source database handle */
+ Btree *pSrc; /* Source b-tree file */
+
+ int rc; /* Backup process error code */
+
+ /* These two variables are set by every call to backup_step(). They are
+ ** read by calls to backup_remaining() and backup_pagecount().
+ */
+ Pgno nRemaining; /* Number of pages left to copy */
+ Pgno nPagecount; /* Total number of pages to copy */
+
+ sqlite3_backup *pNext; /* Next backup associated with source pager */
+};
+
+/*
+** THREAD SAFETY NOTES:
+**
+** Once it has been created using backup_init(), a single sqlite3_backup
+** structure may be accessed via two groups of thread-safe entry points:
+**
+** * Via the sqlite3_backup_XXX() API function backup_step() and
+** backup_finish(). Both these functions obtain the source database
+** handle mutex and the mutex associated with the source BtShared
+** structure, in that order.
+**
+** * Via the BackupUpdate() and BackupRestart() functions, which are
+** invoked by the pager layer to report various state changes in
+** the page cache associated with the source database. The mutex
+** associated with the source database BtShared structure will always
+** be held when either of these functions are invoked.
+**
+** The other sqlite3_backup_XXX() API functions, backup_remaining() and
+** backup_pagecount() are not thread-safe functions. If they are called
+** while some other thread is calling backup_step() or backup_finish(),
+** the values returned may be invalid. There is no way for a call to
+** BackupUpdate() or BackupRestart() to interfere with backup_remaining()
+** or backup_pagecount().
+**
+** Depending on the SQLite configuration, the database handles and/or
+** the Btree objects may have their own mutexes that require locking.
+** Non-sharable Btrees (in-memory databases for example), do not have
+** associated mutexes.
+*/
+
+/*
+** Return a pointer corresponding to database zDb (i.e. "main", "temp")
+** in connection handle pDb. If such a database cannot be found, return
+** a NULL pointer and write an error message to pErrorDb.
+**
+** If the "temp" database is requested, it may need to be opened by this
+** function. If an error occurs while doing so, return 0 and write an
+** error message to pErrorDb.
+*/
+static Btree *findBtree(sqlite3 *pErrorDb, sqlite3 *pDb, const char *zDb){
+ int i = sqlite3FindDbName(pDb, zDb);
+
+ if( i==1 ){
+ Parse sParse;
+ memset(&sParse, 0, sizeof(sParse));
+ sParse.db = pDb;
+ if( sqlite3OpenTempDatabase(&sParse) ){
+ sqlite3ErrorClear(&sParse);
+ sqlite3Error(pErrorDb, sParse.rc, "%s", sParse.zErrMsg);
+ return 0;
+ }
+ assert( sParse.zErrMsg==0 );
+ }
+
+ if( i<0 ){
+ sqlite3Error(pErrorDb, SQLITE_ERROR, "unknown database %s", zDb);
+ return 0;
+ }
+
+ return pDb->aDb[i].pBt;
+}
+
+/*
+** Create an sqlite3_backup process to copy the contents of zSrcDb from
+** connection handle pSrcDb to zDestDb in pDestDb. If successful, return
+** a pointer to the new sqlite3_backup object.
+**
+** If an error occurs, NULL is returned and an error code and error message
+** stored in database handle pDestDb.
+*/
+sqlite3_backup *sqlite3_backup_init(
+ sqlite3* pDestDb, /* Database to write to */
+ const char *zDestDb, /* Name of database within pDestDb */
+ sqlite3* pSrcDb, /* Database connection to read from */
+ const char *zSrcDb /* Name of database within pSrcDb */
+){
+ sqlite3_backup *p; /* Value to return */
+
+ /* Lock the source database handle. The destination database
+ ** handle is not locked. The user is required to ensure that no
+ ** other thread accesses the destination handle for the duration
+ ** of the backup operation.
+ */
+ sqlite3_mutex_enter(pSrcDb->mutex);
+
+ if( pSrcDb==pDestDb ){
+ sqlite3Error(
+ pDestDb, SQLITE_ERROR, "Source and destination handles must be distinct"
+ );
+ p = 0;
+ }else {
+ /* Allocate space for a new sqlite3_backup object */
+ p = (sqlite3_backup *)sqlite3_malloc(sizeof(sqlite3_backup));
+ if( !p ){
+ sqlite3Error(pDestDb, SQLITE_NOMEM, 0);
+ }
+ }
+
+ /* If the allocation succeeded, populate the new object. */
+ if( p ){
+ memset(p, 0, sizeof(sqlite3_backup));
+ p->pSrc = findBtree(pDestDb, pSrcDb, zSrcDb);
+ p->pDest = findBtree(pDestDb, pDestDb, zDestDb);
+ p->pDestDb = pDestDb;
+ p->pSrcDb = pSrcDb;
+ p->iNext = 1;
+
+ if( 0==p->pSrc || 0==p->pDest ){
+ /* One (or both) of the named databases did not exist. An error has
+ ** already been written into the pDestDb handle. All that is left
+ ** to do here is free the sqlite3_backup structure.
+ */
+ sqlite3_free(p);
+ p = 0;
+ }
+ }
+
+ /* If everything has gone as planned, attach the backup object to the
+ ** source pager. The source pager calls BackupUpdate() and BackupRestart()
+ ** to notify this module if the source file is modified mid-backup.
+ */
+ if( p ){
+ sqlite3_backup **pp; /* Pointer to head of pagers backup list */
+ sqlite3BtreeEnter(p->pSrc);
+ pp = sqlite3PagerBackupPtr(sqlite3BtreePager(p->pSrc));
+ p->pNext = *pp;
+ *pp = p;
+ sqlite3BtreeLeave(p->pSrc);
+ p->pSrc->nBackup++;
+ }
+
+ sqlite3_mutex_leave(pSrcDb->mutex);
+ return p;
+}
+
+/*
+** Parameter zSrcData points to a buffer containing the data for
+** page iSrcPg from the source database. Copy this data into the
+** destination database.
+*/
+static int backupOnePage(sqlite3_backup *p, Pgno iSrcPg, const u8 *zSrcData){
+ Pager * const pDestPager = sqlite3BtreePager(p->pDest);
+ const int nSrcPgsz = sqlite3BtreeGetPageSize(p->pSrc);
+ int nDestPgsz = sqlite3BtreeGetPageSize(p->pDest);
+ const int nCopy = MIN(nSrcPgsz, nDestPgsz);
+ const i64 iEnd = (i64)iSrcPg*(i64)nSrcPgsz;
+
+ int rc = SQLITE_OK;
+ i64 iOff;
+
+ assert( p->bDestLocked );
+ assert( p->rc==SQLITE_OK );
+ assert( iSrcPg!=PENDING_BYTE_PAGE(p->pSrc->pBt) );
+ assert( zSrcData );
+
+ /* Catch the case where the destination is an in-memory database and the
+ ** page sizes of the source and destination differ.
+ */
+ if( nSrcPgsz!=nDestPgsz && sqlite3PagerIsMemdb(sqlite3BtreePager(p->pDest)) ){
+ rc = SQLITE_READONLY;
+ }
+
+ /* This loop runs once for each destination page spanned by the source
+ ** page. For each iteration, variable iOff is set to the byte offset
+ ** of the destination page.
+ */
+ for(iOff=iEnd-(i64)nSrcPgsz; rc==SQLITE_OK && iOff<iEnd; iOff+=nDestPgsz){
+ DbPage *pDestPg = 0;
+ Pgno iDest = (Pgno)(iOff/nDestPgsz)+1;
+ if( iDest==PENDING_BYTE_PAGE(p->pDest->pBt) ) continue;
+ if( SQLITE_OK==(rc = sqlite3PagerGet(pDestPager, iDest, &pDestPg))
+ && SQLITE_OK==(rc = sqlite3PagerWrite(pDestPg))
+ ){
+ const u8 *zIn = &zSrcData[iOff%nSrcPgsz];
+ u8 *zDestData = sqlite3PagerGetData(pDestPg);
+ u8 *zOut = &zDestData[iOff%nDestPgsz];
+
+ /* Copy the data from the source page into the destination page.
+ ** Then clear the Btree layer MemPage.isInit flag. Both this module
+ ** and the pager code use this trick (clearing the first byte
+ ** of the page 'extra' space to invalidate the Btree layers
+ ** cached parse of the page). MemPage.isInit is marked
+ ** "MUST BE FIRST" for this purpose.
+ */
+ memcpy(zOut, zIn, nCopy);
+ ((u8 *)sqlite3PagerGetExtra(pDestPg))[0] = 0;
+ }
+ sqlite3PagerUnref(pDestPg);
+ }
+
+ return rc;
+}
+
+/*
+** Copy nPage pages from the source b-tree to the destination.
+*/
+int sqlite3_backup_step(sqlite3_backup *p, int nPage){
+ int rc;
+
+ sqlite3_mutex_enter(p->pSrcDb->mutex);
+ sqlite3BtreeEnter(p->pSrc);
+
+ rc = p->rc;
+ if( rc==SQLITE_OK ){
+ Pager * const pSrcPager = sqlite3BtreePager(p->pSrc); /* Source pager */
+ Pager * const pDestPager = sqlite3BtreePager(p->pDest); /* Dest pager */
+ int ii; /* Iterator variable */
+ int nSrcPage; /* 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_LOCKED immediately.
+ */
+ if( p->pDestDb && p->pSrc->pBt->inTransaction==TRANS_WRITE ){
+ rc = SQLITE_LOCKED;
+ }
+
+ /* Lock the destination database, if it is not locked already. */
+ if( SQLITE_OK==rc && p->bDestLocked==0
+ && SQLITE_OK==(rc = sqlite3BtreeBeginTrans(p->pDest, 2))
+ ){
+ p->bDestLocked = 1;
+ rc = sqlite3BtreeGetMeta(p->pDest, 1, &p->iDestSchema);
+ }
+
+ /* 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);
+ bCloseTrans = 1;
+ }
+
+ /* Now that there is a read-lock on the source database, query the
+ ** source pager for the number of pages in the database.
+ */
+ if( rc==SQLITE_OK ){
+ rc = sqlite3PagerPagecount(pSrcPager, &nSrcPage);
+ }
+ for(ii=0; ii<nPage && p->iNext<=nSrcPage && rc==SQLITE_OK; 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);
+ if( rc==SQLITE_OK ){
+ rc = backupOnePage(p, iSrcPg, sqlite3PagerGetData(pSrcPg));
+ sqlite3PagerUnref(pSrcPg);
+ }
+ }
+ p->iNext++;
+ }
+ if( rc==SQLITE_OK ){
+ p->nPagecount = nSrcPage;
+ p->nRemaining = nSrcPage+1-p->iNext;
+ if( p->iNext>nSrcPage ){
+ rc = SQLITE_DONE;
+ }
+ }
+
+ if( rc==SQLITE_DONE ){
+ const int nSrcPagesize = sqlite3BtreeGetPageSize(p->pSrc);
+ const int nDestPagesize = sqlite3BtreeGetPageSize(p->pDest);
+ int nDestTruncate;
+ sqlite3_file *pFile = 0;
+ i64 iSize;
+
+ /* 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.
+ */
+ sqlite3BtreeUpdateMeta(p->pDest, 1, p->iDestSchema+1);
+
+ /* 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.
+ */
+ if( nSrcPagesize<nDestPagesize ){
+ int ratio = nDestPagesize/nSrcPagesize;
+ nDestTruncate = (nSrcPage+ratio-1)/ratio;
+ }else{
+ nDestTruncate = nSrcPage * (nSrcPagesize/nDestPagesize);
+ }
+ sqlite3PagerTruncateImage(pDestPager, nDestTruncate);
+
+ if( nSrcPagesize<nDestPagesize ){
+ /* 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.
+ */
+ iSize = (i64)nSrcPagesize * (i64)nSrcPage;
+ pFile = sqlite3PagerFile(pDestPager);
+ assert( pFile );
+ if( SQLITE_OK==(rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 1))
+ && SQLITE_OK==(rc = sqlite3OsTruncate(pFile, iSize))
+ && SQLITE_OK==(rc = sqlite3PagerSync(pDestPager))
+ ){
+ i64 iOff;
+ i64 iEnd = MIN(PENDING_BYTE + nDestPagesize, iSize);
+ for(
+ iOff=PENDING_BYTE+nSrcPagesize;
+ rc==SQLITE_OK && iOff<iEnd;
+ iOff+=nSrcPagesize
+ ){
+ PgHdr *pSrcPg = 0;
+ const Pgno iSrcPg = (iOff/nSrcPagesize)+1;
+ rc = sqlite3PagerGet(pSrcPager, iSrcPg, &pSrcPg);
+ if( rc==SQLITE_OK ){
+ u8 *zData = sqlite3PagerGetData(pSrcPg);
+ rc = sqlite3OsWrite(pFile, zData, nSrcPagesize, iOff);
+ }
+ sqlite3PagerUnref(pSrcPg);
+ }
+ }
+ }else{
+ rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 0);
+ }
+
+ /* Finish committing the transaction to the destination database. */
+ if( SQLITE_OK==rc
+ && SQLITE_OK==(rc = sqlite3BtreeCommitPhaseTwo(p->pDest))
+ ){
+ 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);
+ assert( rc2==SQLITE_OK );
+ }
+
+ if( rc!=SQLITE_LOCKED && rc!=SQLITE_BUSY ){
+ p->rc = rc;
+ }
+ }
+ sqlite3BtreeLeave(p->pSrc);
+ sqlite3_mutex_leave(p->pSrcDb->mutex);
+ return rc;
+}
+
+/*
+** Release all resources associated with an sqlite3_backup* handle.
+*/
+int sqlite3_backup_finish(sqlite3_backup *p){
+ sqlite3_backup **pp; /* Ptr to head of pagers backup list */
+ sqlite3_mutex *mutex; /* Mutex to protect source database */
+ int rc; /* Value to return */
+
+ /* Enter the mutexes */
+ sqlite3_mutex_enter(p->pSrcDb->mutex);
+ sqlite3BtreeEnter(p->pSrc);
+ mutex = p->pSrcDb->mutex;
+
+ /* Detach this backup from the source pager. */
+ if( p->pDestDb ){
+ pp = sqlite3PagerBackupPtr(sqlite3BtreePager(p->pSrc));
+ while( *pp!=p ){
+ pp = &(*pp)->pNext;
+ }
+ *pp = p->pNext;
+ p->pSrc->nBackup--;
+ }
+
+ /* If a transaction is still open on the Btree, roll it back. */
+ sqlite3BtreeRollback(p->pDest);
+
+ /* Set the error code of the destination database handle. */
+ rc = (p->rc==SQLITE_DONE) ? SQLITE_OK : p->rc;
+ sqlite3Error(p->pDestDb, rc, 0);
+
+ /* Exit the mutexes and free the backup context structure. */
+ sqlite3BtreeLeave(p->pSrc);
+ if( p->pDestDb ){
+ sqlite3_free(p);
+ }
+ sqlite3_mutex_leave(mutex);
+ return rc;
+}
+
+/*
+** Return the number of pages still to be backed up as of the most recent
+** call to sqlite3_backup_step().
+*/
+int sqlite3_backup_remaining(sqlite3_backup *p){
+ return p->nRemaining;
+}
+
+/*
+** Return the total number of pages in the source database as of the most
+** recent call to sqlite3_backup_step().
+*/
+int sqlite3_backup_pagecount(sqlite3_backup *p){
+ return p->nPagecount;
+}
+
+/*
+** This function is called after the contents of page iPage of the
+** source database have been modified. If page iPage has already been
+** copied into the destination database, then the data written to the
+** destination is now invalidated. The destination copy of iPage needs
+** to be updated with the new data before the backup operation is
+** complete.
+**
+** It is assumed that the mutex associated with the BtShared object
+** corresponding to the source database is held when this function is
+** called.
+*/
+void sqlite3BackupUpdate(sqlite3_backup *pBackup, Pgno iPage, const u8 *aData){
+ sqlite3_backup *p; /* Iterator variable */
+ for(p=pBackup; p; p=p->pNext){
+ assert( sqlite3_mutex_held(p->pSrc->pBt->mutex) );
+ if( p->rc==SQLITE_OK && iPage<p->iNext ){
+ /* The backup process p has already copied page iPage. But now it
+ ** has been modified by a transaction on the source pager. Copy
+ ** the new data into the backup.
+ */
+ int rc = backupOnePage(p, iPage, aData);
+ if( rc!=SQLITE_OK ){
+ p->rc = rc;
+ }
+ }
+ }
+}
+
+/*
+** Restart the backup process. This is called when the pager layer
+** detects that the database has been modified by an external database
+** connection. In this case there is no way of knowing which of the
+** pages that have been copied into the destination database are still
+** valid and which are not, so the entire process needs to be restarted.
+**
+** It is assumed that the mutex associated with the BtShared object
+** corresponding to the source database is held when this function is
+** called.
+*/
+void sqlite3BackupRestart(sqlite3_backup *pBackup){
+ sqlite3_backup *p; /* Iterator variable */
+ for(p=pBackup; p; p=p->pNext){
+ assert( sqlite3_mutex_held(p->pSrc->pBt->mutex) );
+ p->iNext = 1;
+ }
+}
+
+#ifndef SQLITE_OMIT_VACUUM
+/*
+** Copy the complete content of pBtFrom into pBtTo. A transaction
+** must be active for both files.
+**
+** The size of file pTo may be reduced by this operation. If anything
+** goes wrong, the transaction on pTo is rolled back. If successful, the
+** transaction is committed before returning.
+*/
+int sqlite3BtreeCopyFile(Btree *pTo, Btree *pFrom){
+ int rc;
+ sqlite3_backup b;
+ sqlite3BtreeEnter(pTo);
+ sqlite3BtreeEnter(pFrom);
+
+ /* Set up an sqlite3_backup object. sqlite3_backup.pDestDb must be set
+ ** to 0. This is used by the implementations of sqlite3_backup_step()
+ ** and sqlite3_backup_finish() to detect that they are being called
+ ** from this function, not directly by the user.
+ */
+ memset(&b, 0, sizeof(b));
+ b.pSrcDb = pFrom->db;
+ b.pSrc = pFrom;
+ b.pDest = pTo;
+ b.iNext = 1;
+
+ /* 0x7FFFFFFF is the hard limit for the number of pages in a database
+ ** file. By passing this as the number of pages to copy to
+ ** sqlite3_backup_step(), we can guarantee that the copy finishes
+ ** within a single call (unless an error occurs). The assert() statement
+ ** checks this assumption - (p->rc) should be set to either SQLITE_DONE
+ ** or an error code.
+ */
+ sqlite3_backup_step(&b, 0x7FFFFFFF);
+ assert( b.rc!=SQLITE_OK );
+ rc = sqlite3_backup_finish(&b);
+ if( rc==SQLITE_OK ){
+ pTo->pBt->pageSizeFixed = 0;
+ }
+
+ sqlite3BtreeLeave(pFrom);
+ sqlite3BtreeLeave(pTo);
+ return rc;
+}
+#endif /* SQLITE_OMIT_VACUUM */
+
diff --git a/src/btree.c b/src/btree.c
index d48f20880..b4a70bd97 100644
--- a/src/btree.c
+++ b/src/btree.c
@@ -9,7 +9,7 @@
** May you share freely, never taking more than you give.
**
*************************************************************************
-** $Id: btree.c,v 1.563 2009/01/31 14:54:07 danielk1977 Exp $
+** $Id: btree.c,v 1.564 2009/02/03 16:51:25 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
@@ -7239,225 +7239,6 @@ const char *sqlite3BtreeGetJournalname(Btree *p){
return sqlite3PagerJournalname(p->pBt->pPager);
}
-#ifndef SQLITE_OMIT_VACUUM
-/*
-** Copy the complete content of pBtFrom into pBtTo. A transaction
-** must be active for both files.
-**
-** The size of file pTo may be reduced by this operation.
-** If anything goes wrong, the transaction on pTo is rolled back.
-**
-** If successful, CommitPhaseOne() may be called on pTo before returning.
-** The caller should finish committing the transaction on pTo by calling
-** sqlite3BtreeCommit().
-*/
-static int btreeCopyFile(Btree *pTo, Btree *pFrom){
- int rc = SQLITE_OK;
- Pgno i;
-
- Pgno nFromPage; /* Number of pages in pFrom */
- Pgno nToPage; /* Number of pages in pTo */
- Pgno nNewPage; /* Number of pages in pTo after the copy */
-
- Pgno iSkip; /* Pending byte page in pTo */
- int nToPageSize; /* Page size of pTo in bytes */
- int nFromPageSize; /* Page size of pFrom in bytes */
-
- BtShared *pBtTo = pTo->pBt;
- BtShared *pBtFrom = pFrom->pBt;
- pBtTo->db = pTo->db;
- pBtFrom->db = pFrom->db;
-
- nToPageSize = pBtTo->pageSize;
- nFromPageSize = pBtFrom->pageSize;
-
- assert( pTo->inTrans==TRANS_WRITE );
- assert( pFrom->inTrans==TRANS_WRITE );
- if( NEVER(pBtTo->pCursor) ){
- return SQLITE_BUSY;
- }
-
- nToPage = pagerPagecount(pBtTo);
- nFromPage = pagerPagecount(pBtFrom);
- iSkip = PENDING_BYTE_PAGE(pBtTo);
-
- /* Variable nNewPage is the number of pages required to store the
- ** contents of pFrom using the current page-size of pTo.
- */
- nNewPage = (Pgno)
- (((i64)nFromPage*(i64)nFromPageSize+(i64)nToPageSize-1)/(i64)nToPageSize);
-
- for(i=1; rc==SQLITE_OK && (i<=nToPage || i<=nNewPage); i++){
-
- /* Journal the original page.
- **
- ** iSkip is the page number of the locking page (PENDING_BYTE_PAGE)
- ** in database *pTo (before the copy). This page is never written
- ** into the journal file. Unless i==iSkip or the page was not
- ** present in pTo before the copy operation, journal page i from pTo.
- */
- if( i!=iSkip && i<=nToPage ){
- DbPage *pDbPage = 0;
- rc = sqlite3PagerGet(pBtTo->pPager, i, &pDbPage);
- if( rc==SQLITE_OK ){
- rc = sqlite3PagerWrite(pDbPage);
- if( rc==SQLITE_OK && i>nFromPage ){
- /* Yeah. It seems wierd to call DontWrite() right after Write(). But
- ** that is because the names of those procedures do not exactly
- ** represent what they do. Write() really means "put this page in the
- ** rollback journal and mark it as dirty so that it will be written
- ** to the database file later." DontWrite() undoes the second part of
- ** that and prevents the page from being written to the database. The
- ** page is still on the rollback journal, though. And that is the
- ** whole point of this block: to put pages on the rollback journal.
- */
- sqlite3PagerDontWrite(pDbPage);
- }
- sqlite3PagerUnref(pDbPage);
- }
- }
-
- /* Overwrite the data in page i of the target database */
- if( rc==SQLITE_OK && i!=iSkip && i<=nNewPage ){
-
- DbPage *pToPage = 0;
- sqlite3_int64 iOff;
-
- rc = sqlite3PagerGet(pBtTo->pPager, i, &pToPage);
- if( rc==SQLITE_OK ){
- rc = sqlite3PagerWrite(pToPage);
- }
-
- for(
- iOff=(i-1)*nToPageSize;
- rc==SQLITE_OK && iOff<i*nToPageSize;
- iOff += nFromPageSize
- ){
- DbPage *pFromPage = 0;
- Pgno iFrom = (Pgno)(iOff/nFromPageSize)+1;
-
- if( iFrom==PENDING_BYTE_PAGE(pBtFrom) ){
- continue;
- }
-
- rc = sqlite3PagerGet(pBtFrom->pPager, iFrom, &pFromPage);
- if( rc==SQLITE_OK ){
- char *zTo = sqlite3PagerGetData(pToPage);
- char *zFrom = sqlite3PagerGetData(pFromPage);
- int nCopy;
-
- if( nFromPageSize>=nToPageSize ){
- zFrom += ((i-1)*nToPageSize - ((iFrom-1)*nFromPageSize));
- nCopy = nToPageSize;
- }else{
- zTo += (((iFrom-1)*nFromPageSize) - (i-1)*nToPageSize);
- nCopy = nFromPageSize;
- }
-
- memcpy(zTo, zFrom, nCopy);
- sqlite3PagerUnref(pFromPage);
- }
- }
-
- if( pToPage ){
- MemPage *p = (MemPage *)sqlite3PagerGetExtra(pToPage);
- p->isInit = 0;
- sqlite3PagerUnref(pToPage);
- }
- }
- }
-
- /* If things have worked so far, the database file may need to be
- ** truncated. The complex part is that it may need to be truncated to
- ** a size that is not an integer multiple of nToPageSize - the current
- ** page size used by the pager associated with B-Tree pTo.
- **
- ** For example, say the page-size of pTo is 2048 bytes and the original
- ** number of pages is 5 (10 KB file). If pFrom has a page size of 1024
- ** bytes and 9 pages, then the file needs to be truncated to 9KB.
- */
- if( rc==SQLITE_OK ){
- sqlite3_file *pFile = sqlite3PagerFile(pBtTo->pPager);
- i64 iSize = (i64)nFromPageSize * (i64)nFromPage;
- i64 iNow = (i64)((nToPage>nNewPage)?nToPage:nNewPage) * (i64)nToPageSize;
- i64 iPending = ((i64)PENDING_BYTE_PAGE(pBtTo)-1) *(i64)nToPageSize;
-
- assert( iSize<=iNow );
-
- /* Commit phase one syncs the journal file associated with pTo
- ** containing the original data. It does not sync the database file
- ** itself. After doing this it is safe to use OsTruncate() and other
- ** file APIs on the database file directly.
- */
- pBtTo->db = pTo->db;
- if( nFromPageSize==nToPageSize ){
- sqlite3PagerTruncateImage(pBtTo->pPager, nFromPage);
- iNow = iSize;
- }
- rc = sqlite3PagerCommitPhaseOne(pBtTo->pPager, 0, 1);
- if( iSize<iNow && rc==SQLITE_OK ){
- rc = sqlite3OsTruncate(pFile, iSize);
- }
-
- /* The loop that copied data from database pFrom to pTo did not
- ** populate the locking page of database pTo. If the page-size of
- ** pFrom is smaller than that of pTo, this means some data will
- ** not have been copied.
- **
- ** This block copies the missing data from database pFrom to pTo
- ** using file APIs. This is safe because at this point we know that
- ** all of the original data from pTo has been synced into the
- ** journal file. At this point it would be safe to do anything at
- ** all to the database file except truncate it to zero bytes.
- */
- if( rc==SQLITE_OK && nFromPageSize<nToPageSize && iSize>iPending){
- i64 iOff;
- for(
- iOff=iPending;
- rc==SQLITE_OK && iOff<(iPending+nToPageSize);
- iOff += nFromPageSize
- ){
- DbPage *pFromPage = 0;
- Pgno iFrom = (Pgno)(iOff/nFromPageSize)+1;
-
- if( iFrom==PENDING_BYTE_PAGE(pBtFrom) || iFrom>nFromPage ){
- continue;
- }
-
- rc = sqlite3PagerGet(pBtFrom->pPager, iFrom, &pFromPage);
- if( rc==SQLITE_OK ){
- char *zFrom = sqlite3PagerGetData(pFromPage);
- rc = sqlite3OsWrite(pFile, zFrom, nFromPageSize, iOff);
- sqlite3PagerUnref(pFromPage);
- }
- }
- }
- }
-
- /* Sync the database file */
- if( rc==SQLITE_OK ){
- rc = sqlite3PagerSync(pBtTo->pPager);
- }
- if( rc==SQLITE_OK ){
- pBtTo->pageSizeFixed = 0;
- }else{
- sqlite3BtreeRollback(pTo);
- }
-
- return rc;
-}
-int sqlite3BtreeCopyFile(Btree *pTo, Btree *pFrom){
- int rc;
- sqlite3BtreeEnter(pTo);
- sqlite3BtreeEnter(pFrom);
- rc = btreeCopyFile(pTo, pFrom);
- sqlite3BtreeLeave(pFrom);
- sqlite3BtreeLeave(pTo);
- return rc;
-}
-
-#endif /* SQLITE_OMIT_VACUUM */
-
/*
** Return non-zero if a transaction is active.
*/
@@ -7483,6 +7264,12 @@ int sqlite3BtreeIsInReadTrans(Btree *p){
return p->inTrans!=TRANS_NONE;
}
+int sqlite3BtreeIsInBackup(Btree *p){
+ assert( p );
+ assert( sqlite3_mutex_held(p->db->mutex) );
+ return p->nBackup!=0;
+}
+
/*
** This function returns a pointer to a blob of memory associated with
** a single shared-btree. The memory is used by client code for its own
diff --git a/src/btree.h b/src/btree.h
index 49744583b..dff9fe1be 100644
--- a/src/btree.h
+++ b/src/btree.h
@@ -13,7 +13,7 @@
** subsystem. See comments in the source code for a detailed description
** of what each interface routine does.
**
-** @(#) $Id: btree.h,v 1.107 2009/01/24 11:30:43 drh Exp $
+** @(#) $Id: btree.h,v 1.108 2009/02/03 16:51:25 danielk1977 Exp $
*/
#ifndef _BTREE_H_
#define _BTREE_H_
@@ -98,6 +98,7 @@ int sqlite3BtreeCreateTable(Btree*, int*, int flags);
int sqlite3BtreeIsInTrans(Btree*);
int sqlite3BtreeIsInStmt(Btree*);
int sqlite3BtreeIsInReadTrans(Btree*);
+int sqlite3BtreeIsInBackup(Btree*);
void *sqlite3BtreeSchema(Btree *, int, void(*)(void *));
int sqlite3BtreeSchemaLocked(Btree *);
int sqlite3BtreeLockTable(Btree *, int, u8);
diff --git a/src/btreeInt.h b/src/btreeInt.h
index 2a97f9ee4..32aec9615 100644
--- a/src/btreeInt.h
+++ b/src/btreeInt.h
@@ -9,7 +9,7 @@
** May you share freely, never taking more than you give.
**
*************************************************************************
-** $Id: btreeInt.h,v 1.41 2009/01/20 17:06:27 danielk1977 Exp $
+** $Id: btreeInt.h,v 1.42 2009/02/03 16:51:25 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
@@ -324,6 +324,7 @@ struct Btree {
u8 sharable; /* True if we can share pBt with another db */
u8 locked; /* True if db currently has pBt locked */
int wantToLock; /* Number of nested calls to sqlite3BtreeEnter() */
+ int nBackup; /* Number of backup operations reading this btree */
Btree *pNext; /* List of other sharable Btrees from the same db */
Btree *pPrev; /* Back pointer of the same list */
};
diff --git a/src/build.c b/src/build.c
index 300546f0e..b54bfe06c 100644
--- a/src/build.c
+++ b/src/build.c
@@ -22,7 +22,7 @@
** COMMIT
** ROLLBACK
**
-** $Id: build.c,v 1.514 2009/02/03 15:50:34 drh Exp $
+** $Id: build.c,v 1.515 2009/02/03 16:51:25 danielk1977 Exp $
*/
#include "sqliteInt.h"
@@ -621,31 +621,41 @@ void sqlite3OpenMasterTable(Parse *p, int iDb){
}
/*
-** The token *pName contains the name of a database (either "main" or
-** "temp" or the name of an attached db). This routine returns the
-** index of the named database in db->aDb[], or -1 if the named db
-** does not exist.
+** Parameter zName points to a nul-terminated buffer containing the name
+** of a database ("main", "temp" or the name of an attached db). This
+** function returns the index of the named database in db->aDb[], or
+** -1 if the named db cannot be found.
*/
-int sqlite3FindDb(sqlite3 *db, Token *pName){
- int i = -1; /* Database number */
- int n; /* Number of characters in the name */
- Db *pDb; /* A database whose name space is being searched */
- char *zName; /* Name we are searching for */
-
- zName = sqlite3NameFromToken(db, pName);
+int sqlite3FindDbName(sqlite3 *db, const char *zName){
+ int i = -1; /* Database number */
if( zName ){
- n = sqlite3Strlen30(zName);
+ Db *pDb;
+ int n = sqlite3Strlen30(zName);
for(i=(db->nDb-1), pDb=&db->aDb[i]; i>=0; i--, pDb--){
if( (!OMIT_TEMPDB || i!=1 ) && n==sqlite3Strlen30(pDb->zName) &&
0==sqlite3StrICmp(pDb->zName, zName) ){
break;
}
}
- sqlite3DbFree(db, zName);
}
return i;
}
+/*
+** The token *pName contains the name of a database (either "main" or
+** "temp" or the name of an attached db). This routine returns the
+** index of the named database in db->aDb[], or -1 if the named db
+** does not exist.
+*/
+int sqlite3FindDb(sqlite3 *db, Token *pName){
+ int i; /* Database number */
+ char *zName; /* Name we are searching for */
+ zName = sqlite3NameFromToken(db, pName);
+ i = sqlite3FindDbName(db, zName);
+ sqlite3DbFree(db, zName);
+ return i;
+}
+
/* The table or view or trigger name is passed to this routine via tokens
** pName1 and pName2. If the table name was fully qualified, for example:
**
diff --git a/src/main.c b/src/main.c
index f104e41ec..58f5443ca 100644
--- a/src/main.c
+++ b/src/main.c
@@ -14,7 +14,7 @@
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
-** $Id: main.c,v 1.524 2009/02/03 15:50:34 drh Exp $
+** $Id: main.c,v 1.525 2009/02/03 16:51:25 danielk1977 Exp $
*/
#include "sqliteInt.h"
@@ -603,6 +603,16 @@ int sqlite3_close(sqlite3 *db){
}
assert( sqlite3SafetyCheckSickOrOk(db) );
+ for(j=0; j<db->nDb; j++){
+ Btree *pBt = db->aDb[j].pBt;
+ if( pBt && sqlite3BtreeIsInBackup(pBt) ){
+ sqlite3Error(db, SQLITE_BUSY,
+ "Unable to close due to unfinished backup operation");
+ sqlite3_mutex_leave(db->mutex);
+ return SQLITE_BUSY;
+ }
+ }
+
/* Free any outstanding Savepoint structures. */
sqlite3CloseSavepoints(db);
diff --git a/src/pager.c b/src/pager.c
index 820e8bcab..10c09e749 100644
--- a/src/pager.c
+++ b/src/pager.c
@@ -18,7 +18,7 @@
** file simultaneously, or one process from reading the database while
** another is writing.
**
-** @(#) $Id: pager.c,v 1.561 2009/01/31 14:54:07 danielk1977 Exp $
+** @(#) $Id: pager.c,v 1.562 2009/02/03 16:51:25 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
@@ -306,6 +306,7 @@ struct Pager {
char *pTmpSpace; /* Pager.pageSize bytes of space for tmp use */
i64 journalSizeLimit; /* Size limit for persistent journal files */
PCache *pPCache; /* Pointer to page cache object */
+ sqlite3_backup *pBackup; /* Pointer to list of ongoing backup processes */
};
/*
@@ -1039,9 +1040,12 @@ static PgHdr *pager_lookup(Pager *pPager, Pgno pgno){
/*
** Unless the pager is in error-state, discard all in-memory pages. If
** the pager is in error-state, then this call is a no-op.
+**
+** TODO: Why can we not reset the pager while in error state?
*/
static void pager_reset(Pager *pPager){
if( SQLITE_OK==pPager->errCode ){
+ sqlite3BackupRestart(pPager->pBackup);
sqlite3PcacheClear(pPager->pPCache);
}
}
@@ -1513,6 +1517,7 @@ static int pager_playback_one_page(
if( pgno>pPager->dbFileSize ){
pPager->dbFileSize = pgno;
}
+ sqlite3BackupUpdate(pPager->pBackup, pgno, aData);
}else if( !isMainJrnl && pPg==0 ){
/* If this is a rollback of a savepoint and data was not written to
** the database and the page is not in-memory, there is a potential
@@ -2875,6 +2880,9 @@ static int pager_write_pagelist(PgHdr *pList){
pPager->dbFileSize = pgno;
}
+ /* Update any backup objects copying the contents of this pager. */
+ sqlite3BackupUpdate(pPager->pBackup, pgno, (u8 *)pData);
+
PAGERTRACE(("STORE %d page %d hash(%08x)\n",
PAGERID(pPager), pgno, pager_pagehash(pList)));
IOTRACE(("PGOUT %p %d\n", pPager, pgno));
@@ -3549,7 +3557,7 @@ static int pagerSharedLock(Pager *pPager){
** playing back the hot-journal so that we don't end up with
** an inconsistent cache.
*/
- sqlite3PcacheClear(pPager->pPCache);
+ pager_reset(pPager);
rc = pager_playback(pPager, 1);
if( rc!=SQLITE_OK ){
rc = pager_error(pPager, rc);
@@ -4436,7 +4444,9 @@ int sqlite3PagerCommitPhaseOne(
/* If this is an in-memory db, or no pages have been written to, or this
** function has already been called, it is a no-op.
*/
- if( pPager->state!=PAGER_SYNCED && !MEMDB && pPager->dbModified ){
+ if( MEMDB && pPager->dbModified ){
+ sqlite3BackupRestart(pPager->pBackup);
+ }else if( pPager->state!=PAGER_SYNCED && pPager->dbModified ){
/* The following block updates the change-counter. Exactly how it
** does this depends on whether or not the atomic-update optimization
@@ -4747,10 +4757,14 @@ int *sqlite3PagerStats(Pager *pPager){
a[10] = pPager->nWrite;
return a;
}
+#endif
+
+/*
+** Return true if this is an in-memory pager.
+*/
int sqlite3PagerIsMemdb(Pager *pPager){
return MEMDB;
}
-#endif
/*
** Check that there are at least nSavepoint savepoints open. If there are
@@ -5152,4 +5166,14 @@ i64 sqlite3PagerJournalSizeLimit(Pager *pPager, i64 iLimit){
return pPager->journalSizeLimit;
}
+/*
+** Return a pointer to the pPager->pBackup variable. The backup module
+** in backup.c maintains the content of this variable. This module
+** uses it opaquely as an argument to sqlite3BackupRestart() and
+** sqlite3BackupUpdate() only.
+*/
+sqlite3_backup **sqlite3PagerBackupPtr(Pager *pPager){
+ return &pPager->pBackup;
+}
+
#endif /* SQLITE_OMIT_DISKIO */
diff --git a/src/pager.h b/src/pager.h
index 3d6e4bb85..011f91c40 100644
--- a/src/pager.h
+++ b/src/pager.h
@@ -13,7 +13,7 @@
** subsystem. The page cache subsystem reads and writes a file a page
** at a time and provides a journal for rollback.
**
-** @(#) $Id: pager.h,v 1.99 2009/01/31 14:54:07 danielk1977 Exp $
+** @(#) $Id: pager.h,v 1.100 2009/02/03 16:51:25 danielk1977 Exp $
*/
#ifndef _PAGER_H_
@@ -100,6 +100,7 @@ void sqlite3PagerSetSafetyLevel(Pager*,int,int);
int sqlite3PagerLockingMode(Pager *, int);
int sqlite3PagerJournalMode(Pager *, int);
i64 sqlite3PagerJournalSizeLimit(Pager *, i64);
+sqlite3_backup **sqlite3PagerBackupPtr(Pager*);
/* Functions used to obtain and release page references. */
int sqlite3PagerAcquire(Pager *pPager, Pgno pgno, DbPage **ppPage, int clrFlag);
@@ -135,6 +136,7 @@ sqlite3_file *sqlite3PagerFile(Pager*);
const char *sqlite3PagerJournalname(Pager*);
int sqlite3PagerNosync(Pager*);
void *sqlite3PagerTempSpace(Pager*);
+int sqlite3PagerIsMemdb(Pager*);
/* Functions used to truncate the database file. */
void sqlite3PagerTruncateImage(Pager*,Pgno);
@@ -152,7 +154,6 @@ void sqlite3PagerTruncateImage(Pager*,Pgno);
#ifdef SQLITE_TEST
int *sqlite3PagerStats(Pager*);
void sqlite3PagerRefdump(Pager*);
- int sqlite3PagerIsMemdb(Pager*);
void disable_simulated_io_errors(void);
void enable_simulated_io_errors(void);
#else
diff --git a/src/sqlite.h.in b/src/sqlite.h.in
index 950b09f8d..0d23bf213 100644
--- a/src/sqlite.h.in
+++ b/src/sqlite.h.in
@@ -30,7 +30,7 @@
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
**
-** @(#) $Id: sqlite.h.in,v 1.422 2009/01/23 16:45:01 danielk1977 Exp $
+** @(#) $Id: sqlite.h.in,v 1.423 2009/02/03 16:51:25 danielk1977 Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
@@ -6723,6 +6723,178 @@ struct sqlite3_pcache_methods {
};
/*
+** CAPI3REF: Online Backup API.
+** EXPERIMENTAL
+**
+** This API is used to overwrite the contents of one database with that
+** of another. It is useful either for creating backups of databases or
+** for copying in-memory databases to or from persistent files.
+**
+** Exclusive access is required to the destination database for the
+** duration of the operation. However the source database is only
+** read-locked while it is actually being read, it is not locked
+** continuously for the entire operation. Thus, the backup may be
+** performed on a live database without preventing other users from
+** writing to the database for an extended period of time.
+**
+** To perform a backup operation:
+** <ol>
+** <li>[sqlite3_backup_init()] is called once to initialize the backup,
+** <li>[sqlite3_backup_step()] is called one or more times to transfer
+** the data between the two databases, and finally
+** <li>[sqlite3_backup_finish()] is called to release all resources
+** associated with the backup operation.
+** </ol>
+** There should be exactly one call to sqlite3_backup_finish() for each
+** successful call to sqlite3_backup_init().
+**
+** <b>sqlite3_backup_init()</b>
+**
+** The first two arguments passed to [sqlite3_backup_init()] are the database
+** handle associated with the destination database and the database name
+** used to attach the destination database to the handle. The database name
+** is "main" for the main database, "temp" for the temporary database, or
+** the name specified as part of the ATTACH statement if the destination is
+** an attached database. The third and fourth arguments passed to
+** sqlite3_backup_init() identify the database handle and database name used
+** to access the source database. The values passed for the source and
+** destination database handle parameters must not be the same.
+**
+** If an error occurs within sqlite3_backup_init(), then NULL is returned
+** and an error code and error message written into the database handle
+** passed as the first argument. They may be retrieved using the
+** sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16() functions.
+** Otherwise, if successful, an opaque handle of type sqlite3_backup* is
+** returned. This handle may be used with the sqlite3_backup_step() and
+** sqlite3_backup_finish() functions to perform the specified backup
+** operation.
+**
+** <b>sqlite3_backup_step()</b>
+**
+** Function [sqlite3_backup_step()] is used to copy up to nPage pages between
+** the source and destination databases, where nPage is the value of the
+** second parameter passed to sqlite3_backup_step(). If nPage pages are
+** succesfully copied, but there are still more pages to copy before the
+** backup is complete, it returns SQLITE_OK. If no error occured and there
+** are no more pages to copy, then SQLITE_DONE is returned. If an error
+** occurs, then an SQLite error code is returned. As well as SQLITE_OK and
+** SQLITE_DONE, a call to sqlite3_backup_step() may return SQLITE_READONLY,
+** SQLITE_NOMEM, SQLITE_BUSY, SQLITE_LOCKED or an SQLITE_IOERR_XXX error code.
+**
+** As well as the case where the destination database file was opened for
+** read-only access, sqlite3_backup_step() may return SQLITE_READONLY if
+** the destination is an in-memory database with a different page size
+** from the source database.
+**
+** If sqlite3_backup_step() cannot obtain a required file-system lock, then
+** the busy-handler function is invoked (if one is specified). If the
+** busy-handler returns non-zero before the lock is available, then
+** SQLITE_BUSY is returned to the caller. In this case the call to
+** sqlite3_backup_step() can be retried later. If the source database handle
+** is being used to write to the source database when sqlite3_backup_step()
+** is called, then SQLITE_LOCKED is returned immediately. Again, in this
+** case the call to sqlite3_backup_step() can be retried later on. If
+** SQLITE_IOERR_XXX, SQLITE_NOMEM or SQLITE_READONLY is returned, then
+** there is no point in retrying the call to sqlite3_backup_step(). These
+** errors are considered fatal. At this point the application must accept
+** that the backup operation has failed and pass the backup operation handle
+** to the sqlite3_backup_finish() to release associated resources.
+**
+** Following the first call to sqlite3_backup_step(), an exclusive lock is
+** obtained on the destination file. It is not released until either
+** sqlite3_backup_finish() is called or the backup operation is complete
+** and sqlite3_backup_step() returns SQLITE_DONE. Additionally, each time
+** a call to sqlite3_backup_step() is made a shared lock is obtained on
+** the source database file. This lock is released before the
+** sqlite3_backup_step() call returns. Because the source database is not
+** locked between calls to sqlite3_backup_step(), it may be modified mid-way
+** through the backup procedure. If the source database is modified by an
+** external process or via a database connection other than the one being
+** used by the backup operation, then the backup will be transparently
+** restarted by the next call to sqlite3_backup_step(). If the source
+** database is modified by the using the same database connection as is used
+** by the backup operation, then the backup database is transparently
+** updated at the same time.
+**
+** <b>sqlite3_backup_finish()</b>
+**
+** Once sqlite3_backup_step() has returned SQLITE_DONE, or when the
+** application wishes to abandon the backup operation, the sqlite3_backup*
+** handle should be passed to sqlite3_backup_finish(). This releases all
+** resources associated with the backup operation. If sqlite3_backup_step()
+** has not yet returned SQLITE_DONE, then any active write-transaction on the
+** destination database is rolled back. The sqlite3_backup* handle is invalid
+** and may not be used following a call to sqlite3_backup_finish().
+**
+** The value returned by sqlite3_backup_finish is SQLITE_OK if no error
+** occured, regardless or whether or not sqlite3_backup_step() was called
+** a sufficient number of times to complete the backup operation. Or, if
+** an out-of-memory condition or IO error occured during a call to
+** sqlite3_backup_step() then SQLITE_NOMEM or an SQLITE_IOERR_XXX error code
+** is returned. In this case the error code and an error message are
+** written to the destination database handle.
+**
+** A return of SQLITE_BUSY or SQLITE_LOCKED from sqlite3_backup_step() is
+** not considered an error and does not affect the return value of
+** sqlite3_backup_finish().
+**
+** <b>sqlite3_backup_remaining(), sqlite3_backup_pagecount()</b>
+**
+** Each call to sqlite3_backup_step() sets two values stored internally
+** by an sqlite3_backup* handle. The number of pages still to be backed
+** up, which may be queried by sqlite3_backup_remaining(), and the total
+** number of pages in the source database file, which may be queried by
+** sqlite3_backup_pagecount().
+**
+** The values returned by these functions are only updated by
+** sqlite3_backup_step(). If the source database is modified during a backup
+** operation, then the values are not updated to account for any extra
+** pages that need to be updated or the size of the source database file
+** changing.
+**
+** <b>Concurrent Usage of Database Handles</b>
+**
+** The source database handle may be used by the application for other
+** purposes while a backup operation is underway or being initialized.
+** If SQLite is compiled and configured to support threadsafe database
+** connections, then the source database connection may be used concurrently
+** from within other threads.
+**
+** However, the application must guarantee that the destination database
+** connection handle is not passed to any other API (by any thread) after
+** sqlite3_backup_init() is called and before the corresponding call to
+** sqlite3_backup_finish(). Unfortunately SQLite does not currently check
+** for this, if the application does use the destination database handle
+** for some other purpose during a backup operation, things may appear to
+** work correctly but in fact be subtly malfunctioning.
+**
+** Furthermore, if running in shared cache mode, the application must
+** guarantee that the shared cache used by the destination database
+** is not accessed while the backup is running. In practice this means
+** that the application must guarantee that the file-system file being
+** backed up to is not accessed by any connection within the process,
+** not just the specific connection that was passed to sqlite3_backup_init().
+**
+** The sqlite3_backup handle itself is partially threadsafe. Multiple
+** threads may safely make multiple concurrent calls to sqlite3_backup_step().
+** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
+** APIs are not strictly speaking threadsafe. If they are invoked at the
+** same time as another thread is invoking sqlite3_backup_step() it is
+** possible that they return invalid values.
+*/
+typedef struct sqlite3_backup sqlite3_backup;
+sqlite3_backup *sqlite3_backup_init(
+ sqlite3 *pDest, /* Destination database handle */
+ const char *zDestName, /* Destination database name */
+ sqlite3 *pSource, /* Source database handle */
+ const char *zSourceName /* Source database name */
+);
+int sqlite3_backup_step(sqlite3_backup *p, int nPage);
+int sqlite3_backup_finish(sqlite3_backup *p);
+int sqlite3_backup_remaining(sqlite3_backup *p);
+int sqlite3_backup_pagecount(sqlite3_backup *p);
+
+/*
** Undo the hack that converts floating point types to integer for
** builds on processors without floating point support.
*/
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 287d2c95f..8db2e69e3 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -11,7 +11,7 @@
*************************************************************************
** Internal interface definitions for SQLite.
**
-** @(#) $Id: sqliteInt.h,v 1.830 2009/01/24 11:30:43 drh Exp $
+** @(#) $Id: sqliteInt.h,v 1.831 2009/02/03 16:51:25 danielk1977 Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_
@@ -2552,6 +2552,7 @@ char sqlite3AffinityType(const Token*);
void sqlite3Analyze(Parse*, Token*, Token*);
int sqlite3InvokeBusyHandler(BusyHandler*);
int sqlite3FindDb(sqlite3*, Token*);
+int sqlite3FindDbName(sqlite3 *, const char *);
int sqlite3AnalysisLoad(sqlite3*,int iDB);
void sqlite3DefaultRowEst(Index*);
void sqlite3RegisterLikeFunctions(sqlite3*, int);
@@ -2573,6 +2574,9 @@ char *sqlite3StrAccumFinish(StrAccum*);
void sqlite3StrAccumReset(StrAccum*);
void sqlite3SelectDestInit(SelectDest*,int,int);
+void sqlite3BackupRestart(sqlite3_backup *);
+void sqlite3BackupUpdate(sqlite3_backup *, Pgno, const u8 *);
+
/*
** The interface to the LEMON-generated parser
*/
diff --git a/src/tclsqlite.c b/src/tclsqlite.c
index 0e35f41e4..1516728d5 100644
--- a/src/tclsqlite.c
+++ b/src/tclsqlite.c
@@ -12,7 +12,7 @@
** A TCL Interface to SQLite. Append this file to sqlite3.c and
** compile the whole thing to build a TCL-enabled version of SQLite.
**
-** $Id: tclsqlite.c,v 1.234 2009/01/14 23:38:03 drh Exp $
+** $Id: tclsqlite.c,v 1.235 2009/02/03 16:51:25 danielk1977 Exp $
*/
#include "tcl.h"
#include <errno.h>
@@ -2663,6 +2663,7 @@ int TCLSH_MAIN(int argc, char **argv){
extern int SqlitetestThread_Init(Tcl_Interp*);
extern int SqlitetestOnefile_Init();
extern int SqlitetestOsinst_Init(Tcl_Interp*);
+ extern int Sqlitetestbackup_Init(Tcl_Interp*);
Md5_Init(interp);
Sqliteconfig_Init(interp);
@@ -2686,6 +2687,7 @@ int TCLSH_MAIN(int argc, char **argv){
SqlitetestThread_Init(interp);
SqlitetestOnefile_Init(interp);
SqlitetestOsinst_Init(interp);
+ Sqlitetestbackup_Init(interp);
#ifdef SQLITE_SSE
Sqlitetestsse_Init(interp);
diff --git a/src/test1.c b/src/test1.c
index eff89a7de..326c67daf 100644
--- a/src/test1.c
+++ b/src/test1.c
@@ -13,7 +13,7 @@
** is not included in the SQLite library. It is used for automated
** testing of the SQLite library.
**
-** $Id: test1.c,v 1.346 2009/02/03 16:25:48 drh Exp $
+** $Id: test1.c,v 1.347 2009/02/03 16:51:25 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
@@ -3217,7 +3217,7 @@ static int test_errcode(
}
/*
-** Usage: test_errmsg DB
+** Usage: sqlite3_errmsg DB
**
** Returns the UTF-8 representation of the error message string for the
** most recent sqlite3_* API call.
diff --git a/src/test_backup.c b/src/test_backup.c
new file mode 100644
index 000000000..1a1418d1c
--- /dev/null
+++ b/src/test_backup.c
@@ -0,0 +1,148 @@
+/*
+** 2009 January 28
+**
+** 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.
+**
+*************************************************************************
+**
+** $Id: test_backup.c,v 1.1 2009/02/03 16:51:25 danielk1977 Exp $
+*/
+
+#include "tcl.h"
+#include <sqlite3.h>
+#include <assert.h>
+
+/* These functions are implemented in test1.c. */
+int getDbPointer(Tcl_Interp *, const char *, sqlite3 **);
+const char *sqlite3TestErrorName(int);
+
+static int backupTestCmd(
+ ClientData clientData,
+ Tcl_Interp *interp,
+ int objc,
+ Tcl_Obj *const*objv
+){
+ enum BackupSubCommandEnum {
+ BACKUP_STEP, BACKUP_FINISH, BACKUP_REMAINING, BACKUP_PAGECOUNT
+ };
+ struct BackupSubCommand {
+ const char *zCmd;
+ enum BackupSubCommandEnum eCmd;
+ int nArg;
+ const char *zArg;
+ } aSub[] = {
+ {"step", BACKUP_STEP , 1, "npage" },
+ {"finish", BACKUP_FINISH , 0, "" },
+ {"remaining", BACKUP_REMAINING , 0, "" },
+ {"pagecount", BACKUP_PAGECOUNT , 0, "" },
+ {0, 0, 0, 0}
+ };
+
+ sqlite3_backup *p = (sqlite3_backup *)clientData;
+ int iCmd;
+ int rc;
+
+ rc = Tcl_GetIndexFromObjStruct(
+ interp, objv[1], aSub, sizeof(aSub[0]), "option", 0, &iCmd
+ );
+ if( rc!=TCL_OK ){
+ return rc;
+ }
+ if( objc!=(2 + aSub[iCmd].nArg) ){
+ Tcl_WrongNumArgs(interp, 2, objv, aSub[iCmd].zArg);
+ return TCL_ERROR;
+ }
+
+ switch( aSub[iCmd].eCmd ){
+
+ case BACKUP_FINISH: {
+ Tcl_CmdInfo cmdInfo;
+ Tcl_Command cmd = Tcl_GetCommandFromObj(interp, objv[0]);
+ Tcl_GetCommandInfoFromToken(cmd, &cmdInfo);
+ cmdInfo.deleteProc = 0;
+ Tcl_SetCommandInfoFromToken(cmd, &cmdInfo);
+ Tcl_DeleteCommandFromToken(interp, cmd);
+
+ rc = sqlite3_backup_finish(p);
+ Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_STATIC);
+ break;
+ }
+
+ case BACKUP_STEP: {
+ int nPage;
+ if( TCL_OK!=Tcl_GetIntFromObj(interp, objv[2], &nPage) ){
+ return TCL_ERROR;
+ }
+ rc = sqlite3_backup_step(p, nPage);
+ Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_STATIC);
+ break;
+ }
+
+ case BACKUP_REMAINING:
+ Tcl_SetObjResult(interp, Tcl_NewIntObj(sqlite3_backup_remaining(p)));
+ break;
+
+ case BACKUP_PAGECOUNT:
+ Tcl_SetObjResult(interp, Tcl_NewIntObj(sqlite3_backup_pagecount(p)));
+ break;
+ }
+
+ return TCL_OK;
+}
+
+static void backupTestFinish(ClientData clientData){
+ sqlite3_backup *pBackup = (sqlite3_backup *)clientData;
+ sqlite3_backup_finish(pBackup);
+}
+
+/*
+** sqlite3_backup CMDNAME DESTHANDLE DESTNAME SRCHANDLE SRCNAME
+**
+*/
+static int backupTestInit(
+ ClientData clientData,
+ Tcl_Interp *interp,
+ int objc,
+ Tcl_Obj *const*objv
+){
+ sqlite3_backup *pBackup;
+ sqlite3 *pDestDb;
+ sqlite3 *pSrcDb;
+ const char *zDestName;
+ const char *zSrcName;
+ const char *zCmd;
+
+ if( objc!=6 ){
+ Tcl_WrongNumArgs(
+ interp, 1, objv, "CMDNAME DESTHANDLE DESTNAME SRCHANDLE SRCNAME"
+ );
+ return TCL_ERROR;
+ }
+
+ zCmd = Tcl_GetString(objv[1]);
+ getDbPointer(interp, Tcl_GetString(objv[2]), &pDestDb);
+ zDestName = Tcl_GetString(objv[3]);
+ getDbPointer(interp, Tcl_GetString(objv[4]), &pSrcDb);
+ zSrcName = Tcl_GetString(objv[5]);
+
+ pBackup = sqlite3_backup_init(pDestDb, zDestName, pSrcDb, zSrcName);
+ if( !pBackup ){
+ Tcl_AppendResult(interp, "sqlite3_backup_init() failed", 0);
+ return TCL_ERROR;
+ }
+
+ Tcl_CreateObjCommand(interp, zCmd, backupTestCmd, pBackup, backupTestFinish);
+ Tcl_SetObjResult(interp, objv[1]);
+ return TCL_OK;
+}
+
+int Sqlitetestbackup_Init(Tcl_Interp *interp){
+ Tcl_CreateObjCommand(interp, "sqlite3_backup", backupTestInit, 0, 0);
+ return TCL_OK;
+}
+
diff --git a/src/vacuum.c b/src/vacuum.c
index 2a16df43e..c6227303d 100644
--- a/src/vacuum.c
+++ b/src/vacuum.c
@@ -14,7 +14,7 @@
** Most of the code in this file may be omitted by defining the
** SQLITE_OMIT_VACUUM macro.
**
-** $Id: vacuum.c,v 1.85 2009/01/22 23:04:46 drh Exp $
+** $Id: vacuum.c,v 1.86 2009/02/03 16:51:25 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"
@@ -265,7 +265,6 @@ int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
#ifndef SQLITE_OMIT_AUTOVACUUM
sqlite3BtreeSetAutoVacuum(pMain, sqlite3BtreeGetAutoVacuum(pTemp));
#endif
- rc = sqlite3BtreeCommit(pMain);
}
if( rc==SQLITE_OK ){
diff --git a/src/vdbeaux.c b/src/vdbeaux.c
index 54528ea38..9bc5beff4 100644
--- a/src/vdbeaux.c
+++ b/src/vdbeaux.c
@@ -14,7 +14,7 @@
** to version 2.8.7, all this code was combined into the vdbe.c source file.
** But that file was getting too big so this subroutines were split out.
**
-** $Id: vdbeaux.c,v 1.434 2009/01/20 17:06:27 danielk1977 Exp $
+** $Id: vdbeaux.c,v 1.435 2009/02/03 16:51:25 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"
@@ -1298,7 +1298,7 @@ static int vdbeCommit(sqlite3 *db, Vdbe *p){
if( 0==sqlite3Strlen30(sqlite3BtreeGetFilename(db->aDb[0].pBt))
|| nTrans<=1
){
- for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
+ for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
rc = sqlite3BtreeCommitPhaseOne(pBt, 0);
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-17 18:37:29 +0000