Move codec management from database connections into the pager so that it

will work together with shared cache. (CVS 6782)

FossilOrigin-Name: ed08b53cd64c4ff2c94ef4e48441c5236041c9ca

6 files changed, 60 insertions, 41 deletions

diff --git a/src/btree.c b/src/btree.c
index 8d6a1482d..a83c8115d 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 1.635 2009/06/18 11:29:21 drh Exp $
+** $Id: btree.c,v 1.636 2009/06/18 17:22:39 drh Exp $
 **
 ** This file implements a external (disk-based) database using BTrees.
 ** See the header comment on "btreeInt.h" for additional information.
@@ -1589,7 +1589,7 @@ int sqlite3BtreeOpen(
       pBt->incrVacuum = (get4byte(&zDbHeader[36 + 7*4])?1:0);
 #endif
     }
-    rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize);
+    rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize, nReserve);
     if( rc ) goto btree_open_out;
     pBt->usableSize = pBt->pageSize - nReserve;
     assert( (pBt->pageSize & 7)==0 );  /* 8-byte alignment of pageSize */
@@ -1880,8 +1880,8 @@ int sqlite3BtreeSetPageSize(Btree *p, int pageSize, int nReserve, int iFix){
     assert( !pBt->pPage1 && !pBt->pCursor );
     pBt->pageSize = (u16)pageSize;
     freeTempSpace(pBt);
-    rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize);
   }
+  rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize, nReserve);
   pBt->usableSize = pBt->pageSize - (u16)nReserve;
   if( iFix ) pBt->pageSizeFixed = 1;
   sqlite3BtreeLeave(p);
@@ -2036,7 +2036,8 @@ static int lockBtree(BtShared *pBt){
       pBt->usableSize = (u16)usableSize;
       pBt->pageSize = (u16)pageSize;
       freeTempSpace(pBt);
-      rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize);
+      rc = sqlite3PagerSetPagesize(pBt->pPager, &pBt->pageSize,
+                                   pageSize-usableSize);
       if( rc ) goto page1_init_failed;
       return SQLITE_OK;
     }
diff --git a/src/build.c b/src/build.c
index a159ee43a..53d03b743 100644
--- a/src/build.c
+++ b/src/build.c
@@ -22,7 +22,7 @@
 **     COMMIT
 **     ROLLBACK
 **
-** $Id: build.c,v 1.551 2009/06/16 04:35:39 danielk1977 Exp $
+** $Id: build.c,v 1.552 2009/06/18 17:22:39 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -429,15 +429,6 @@ void sqlite3ResetInternalSchema(sqlite3 *db, int iDb){
   ** schema hash tables and therefore do not have to make any changes
   ** to any of those tables.
   */
-#ifdef SQLITE_HAS_CODEC
-  for(i=0; i<db->nDb; i++){
-    struct Db *pDb = &db->aDb[i];
-    if( pDb->pBt==0 ){
-      if( pDb->pAux && pDb->xFreeAux ) pDb->xFreeAux(pDb->pAux);
-      pDb->pAux = 0;
-    }
-  }
-#endif
   for(i=j=2; i<db->nDb; i++){
     struct Db *pDb = &db->aDb[i];
     if( pDb->pBt==0 ){
diff --git a/src/pager.c b/src/pager.c
index 522a926b5..60ef5678f 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 1.593 2009/06/11 17:32:45 drh Exp $
+** @(#) $Id: pager.c,v 1.594 2009/06/18 17:22:39 drh Exp $
 */
 #ifndef SQLITE_OMIT_DISKIO
 #include "sqliteInt.h"
@@ -104,10 +104,10 @@ int sqlite3PagerTrace=1;  /* True to enable tracing */
 */
 #ifdef SQLITE_HAS_CODEC
 # define CODEC1(P,D,N,X,E) \
-    if( P->xCodec && P->xCodec(P->pCodecArg,D,N,X)==0 ){ E; }
+    if( P->xCodec && P->xCodec(P->pCodec,D,N,X)==0 ){ E; }
 # define CODEC2(P,D,N,X,E,O) \
     if( P->xCodec==0 ){ O=(char*)D; }else \
-    if( (O=(char*)(P->xCodec(P->pCodecArg,D,N,X)))==0 ){ E; }
+    if( (O=(char*)(P->xCodec(P->pCodec,D,N,X)))==0 ){ E; }
 #else
 # define CODEC1(P,D,N,X,E)   /* NO-OP */
 # define CODEC2(P,D,N,X,E,O) O=(char*)D
@@ -290,7 +290,8 @@ struct Pager {
   char dbFileVers[16];        /* Changes whenever database file changes */
   u32 sectorSize;             /* Assumed sector size during rollback */
 
-  int nExtra;                 /* Add this many bytes to each in-memory page */
+  u16 nExtra;                 /* Add this many bytes to each in-memory page */
+  i16 nReserve;               /* Number of unused bytes at end of each page */
   u32 vfsFlags;               /* Flags for sqlite3_vfs.xOpen() */
   int pageSize;               /* Number of bytes in a page */
   Pgno mxPgno;                /* Maximum allowed size of the database */
@@ -305,7 +306,9 @@ struct Pager {
   void (*xReiniter)(DbPage*); /* Call this routine when reloading pages */
 #ifdef SQLITE_HAS_CODEC
   void *(*xCodec)(void*,void*,Pgno,int); /* Routine for en/decoding data */
-  void *pCodecArg;            /* First argument to xCodec() */
+  void (*xCodecSizeChng)(void*,int,int); /* Notify of page size changes */
+  void (*xCodecFree)(void*);             /* Destructor for the codec */
+  void *pCodec;               /* First argument to xCodec... methods */
 #endif
   char *pTmpSpace;            /* Pager.pageSize bytes of space for tmp use */
   i64 journalSizeLimit;       /* Size limit for persistent journal files */
@@ -927,7 +930,7 @@ static int readJournalHdr(
     ** PagerSetPagesize() is tested.
     */
     iPageSize16 = (u16)iPageSize;
-    rc = sqlite3PagerSetPagesize(pPager, &iPageSize16);
+    rc = sqlite3PagerSetPagesize(pPager, &iPageSize16, -1);
     testcase( rc!=SQLITE_OK );
     assert( rc!=SQLITE_OK || iPageSize16==(u16)iPageSize );
 
@@ -2362,6 +2365,21 @@ void sqlite3PagerSetReiniter(Pager *pPager, void (*xReinit)(DbPage*)){
 }
 
 /*
+** Report the current page size and number of reserved bytes back
+** to the codec.
+*/
+#ifdef SQLITE_HAS_CODEC
+static void pagerReportSize(Pager *pPager){
+  if( pPager->xCodecSizeChng ){
+    pPager->xCodecSizeChng(pPager->pCodec, pPager->pageSize,
+                           (int)pPager->nReserve);
+  }
+}
+#else
+# define pagerReportSize(X)     /* No-op if we do not support a codec */
+#endif
+
+/*
 ** Change the page size used by the Pager object. The new page size 
 ** is passed in *pPageSize.
 **
@@ -2391,7 +2409,7 @@ void sqlite3PagerSetReiniter(Pager *pPager, void (*xReinit)(DbPage*)){
 ** function was called, or because the memory allocation attempt failed, 
 ** then *pPageSize is set to the old, retained page size before returning.
 */
-int sqlite3PagerSetPagesize(Pager *pPager, u16 *pPageSize){
+int sqlite3PagerSetPagesize(Pager *pPager, u16 *pPageSize, int nReserve){
   int rc = pPager->errCode;
   if( rc==SQLITE_OK ){
     u16 pageSize = *pPageSize;
@@ -2412,6 +2430,10 @@ int sqlite3PagerSetPagesize(Pager *pPager, u16 *pPageSize){
       }
     }
     *pPageSize = (u16)pPager->pageSize;
+    if( nReserve<0 ) nReserve = pPager->nReserve;
+    assert( nReserve>=0 && nReserve<1000 );
+    pPager->nReserve = (i16)nReserve;
+    pagerReportSize(pPager);
   }
   return rc;
 }
@@ -2660,6 +2682,10 @@ int sqlite3PagerClose(Pager *pPager){
   sqlite3PageFree(pPager->pTmpSpace);
   sqlite3PcacheClose(pPager->pPCache);
 
+#ifdef SQLITE_HAS_CODEC
+  if( pPager->xCodecFree ) pPager->xCodecFree(pPager->pCodec);
+#endif
+
   assert( !pPager->aSavepoint && !pPager->pInJournal );
   assert( !isOpen(pPager->jfd) && !isOpen(pPager->sjfd) );
 
@@ -3281,7 +3307,7 @@ int sqlite3PagerOpen(
   */
   if( rc==SQLITE_OK ){
     assert( pPager->memDb==0 );
-    rc = sqlite3PagerSetPagesize(pPager, &szPageDflt);
+    rc = sqlite3PagerSetPagesize(pPager, &szPageDflt, -1);
     testcase( rc!=SQLITE_OK );
   }
 
@@ -3296,6 +3322,7 @@ int sqlite3PagerOpen(
   }
 
   /* Initialize the PCache object. */
+  assert( nExtra<1000 );
   nExtra = ROUND8(nExtra);
   sqlite3PcacheOpen(szPageDflt, nExtra, !memDb,
                     !memDb?pagerStress:0, (void *)pPager, pPager->pPCache);
@@ -3331,7 +3358,7 @@ int sqlite3PagerOpen(
   /* pPager->pFirst = 0; */
   /* pPager->pFirstSynced = 0; */
   /* pPager->pLast = 0; */
-  pPager->nExtra = nExtra;
+  pPager->nExtra = (u16)nExtra;
   pPager->journalSizeLimit = SQLITE_DEFAULT_JOURNAL_SIZE_LIMIT;
   assert( isOpen(pPager->fd) || tempFile );
   setSectorSize(pPager);
@@ -5044,15 +5071,24 @@ int sqlite3PagerNosync(Pager *pPager){
 
 #ifdef SQLITE_HAS_CODEC
 /*
-** Set the codec for this pager
+** Set or retrieve the codec for this pager
 */
-void sqlite3PagerSetCodec(
+static void sqlite3PagerSetCodec(
   Pager *pPager,
   void *(*xCodec)(void*,void*,Pgno,int),
-  void *pCodecArg
+  void (*xCodecSizeChng)(void*,int,int),
+  void (*xCodecFree)(void*),
+  void *pCodec
 ){
+  if( pPager->xCodecFree ) pPager->xCodecFree(pPager->pCodec);
   pPager->xCodec = xCodec;
-  pPager->pCodecArg = pCodecArg;
+  pPager->xCodecSizeChng = xCodecSizeChng;
+  pPager->xCodecFree = xCodecFree;
+  pPager->pCodec = pCodec;
+  pagerReportSize(pPager);
+}
+static void *sqlite3PagerGetCodec(Pager *pPager){
+  return pPager->pCodec;
 }
 #endif
 
diff --git a/src/pager.h b/src/pager.h
index a0110f859..aed165f06 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 1.101 2009/04/30 09:10:38 danielk1977 Exp $
+** @(#) $Id: pager.h,v 1.102 2009/06/18 17:22:39 drh Exp $
 */
 
 #ifndef _PAGER_H_
@@ -93,7 +93,7 @@ int sqlite3PagerReadFileheader(Pager*, int, unsigned char*);
 /* Functions used to configure a Pager object. */
 void sqlite3PagerSetBusyhandler(Pager*, int(*)(void *), void *);
 void sqlite3PagerSetReiniter(Pager*, void(*)(DbPage*));
-int sqlite3PagerSetPagesize(Pager*, u16*);
+int sqlite3PagerSetPagesize(Pager*, u16*, int);
 int sqlite3PagerMaxPageCount(Pager*, int);
 void sqlite3PagerSetCachesize(Pager*, int);
 void sqlite3PagerSetSafetyLevel(Pager*,int,int);
@@ -141,11 +141,6 @@ int sqlite3PagerIsMemdb(Pager*);
 /* Functions used to truncate the database file. */
 void sqlite3PagerTruncateImage(Pager*,Pgno);
 
-/* Used by encryption extensions. */
-#ifdef SQLITE_HAS_CODEC
-  void sqlite3PagerSetCodec(Pager*,void*(*)(void*,void*,Pgno,int),void*);
-#endif
-
 /* Functions to support testing and debugging. */
 #if !defined(NDEBUG) || defined(SQLITE_TEST)
   Pgno sqlite3PagerPagenumber(DbPage*);
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 0601584b8..67fc1344f 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -11,7 +11,7 @@
 *************************************************************************
 ** Internal interface definitions for SQLite.
 **
-** @(#) $Id: sqliteInt.h,v 1.884 2009/06/15 20:45:35 drh Exp $
+** @(#) $Id: sqliteInt.h,v 1.885 2009/06/18 17:22:39 drh Exp $
 */
 #ifndef _SQLITEINT_H_
 #define _SQLITEINT_H_
@@ -645,10 +645,6 @@ struct Db {
   u8 inTrans;          /* 0: not writable.  1: Transaction.  2: Checkpoint */
   u8 safety_level;     /* How aggressive at syncing data to disk */
   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
-#ifdef SQLITE_HAS_CODEC
-  void *pAux;               /* Auxiliary data.  Usually NULL */
-  void (*xFreeAux)(void*);  /* Routine to free pAux */
-#endif
 };
 
 /*
diff --git a/src/test2.c b/src/test2.c
index 4db8eede6..0ea382830 100644
--- a/src/test2.c
+++ b/src/test2.c
@@ -13,7 +13,7 @@
 ** is not included in the SQLite library.  It is used for automated
 ** testing of the SQLite library.
 **
-** $Id: test2.c,v 1.70 2009/02/05 16:31:46 drh Exp $
+** $Id: test2.c,v 1.71 2009/06/18 17:22:39 drh Exp $
 */
 #include "sqliteInt.h"
 #include "tcl.h"
@@ -86,7 +86,7 @@ static int pager_open(
   }
   sqlite3PagerSetCachesize(pPager, nPage);
   pageSize = test_pagesize;
-  sqlite3PagerSetPagesize(pPager, &pageSize);
+  sqlite3PagerSetPagesize(pPager, &pageSize, -1);
   sqlite3_snprintf(sizeof(zBuf),zBuf,"%p",pPager);
   Tcl_AppendResult(interp, zBuf, 0);
   return TCL_OK;