From 2be25bffcad4002b02a08a84eccb6bf72037721d Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Thu, 15 Dec 2011 02:22:16 +0000
Subject: [PATCH 01/10] In the multiplexor, do not try to delete overflow files
 that do not exist. And assume all but the last overflow file is the size of
 the chunk size.

FossilOrigin-Name: a822a80d3cfe42b2fca6f8c9ff11762993114a27
---
 manifest             | 12 ++++++------
 manifest.uuid        |  2 +-
 src/test_multiplex.c |  6 ++++--
 3 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/manifest b/manifest
index e9459b2243..cd4f6d1738 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Merge\sthe\sVFSNAME\sfile-control\saddition\sinto\sthe\snx-devkit\sbranch.
-D 2011-12-14T18:28:18.920
+C In\sthe\smultiplexor,\sdo\snot\stry\sto\sdelete\soverflow\sfiles\sthat\sdo\snot\sexist.\nAnd\sassume\sall\sbut\sthe\slast\soverflow\sfile\sis\sthe\ssize\sof\sthe\schunk\ssize.
+D 2011-12-15T02:22:16.244
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -214,7 +214,7 @@ F src/test_intarray.h 489edb9068bb926583445cb02589344961054207
 F src/test_journal.c 03313c693cca72959dcaaf79f8d76f21c01e19ff
 F src/test_loadext.c df586c27176e3c2cb2e099c78da67bf14379a56e
 F src/test_malloc.c 8d416f29ad8573f32601f6056c9d2b17472e9ad5
-F src/test_multiplex.c 80677a47c75ca6a035d1ac66fb59186ffd4cdd19
+F src/test_multiplex.c cee2474efe6ee92732e43184f62422bc17623d1f
 F src/test_multiplex.h e99c571bc4968b7a9363b661481f3934bfead61d
 F src/test_mutex.c a6bd7b9cf6e19d989e31392b06ac8d189f0d573e
 F src/test_onefile.c 40cf9e212a377a6511469384a64b01e6e34b2eec
@@ -978,7 +978,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P 08bbbd8e38697908ab8ae0f6b512d01c32f7e4da cdbfb553af02d10767a905489d9dfc57fc6be54e
-R d213e3c5e90076919d50d6149e76976e
+P 08c1dc517c1340737a55ad9012b7b06f72899c6f
+R 05ea69e1c214c57dec4ba569476ada26
 U drh
-Z 8e788ffb68fb72b933914781f94a7874
+Z 5b0957f1b7fd94c5b03cf783382a1410
diff --git a/manifest.uuid b/manifest.uuid
index d03e81ee9a..18315cb8d5 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-08c1dc517c1340737a55ad9012b7b06f72899c6f
\ No newline at end of file
+a822a80d3cfe42b2fca6f8c9ff11762993114a27
\ No newline at end of file
diff --git a/src/test_multiplex.c b/src/test_multiplex.c
index f6540d82dc..b9688e34df 100644
--- a/src/test_multiplex.c
+++ b/src/test_multiplex.c
@@ -365,7 +365,9 @@ static void multiplexSubClose(
   sqlite3_file *pSubOpen = pGroup->aReal[iChunk].p;
   if( pSubOpen ){
     pSubOpen->pMethods->xClose(pSubOpen);
-    if( pOrigVfs ) pOrigVfs->xDelete(pOrigVfs, pGroup->aReal[iChunk].z, 0);
+    if( pOrigVfs && pGroup->aReal[iChunk].z ){
+      pOrigVfs->xDelete(pOrigVfs, pGroup->aReal[iChunk].z, 0);
+    }
     sqlite3_free(pGroup->aReal[iChunk].p);
   }
   sqlite3_free(pGroup->aReal[iChunk].z);
@@ -768,7 +770,7 @@ static int multiplexFileSize(sqlite3_file *pConn, sqlite3_int64 *pSize){
         if( rc==SQLITE_OK && sz>pGroup->szChunk ){
           rc = SQLITE_IOERR_FSTAT;
         }
-        *pSize += sz;
+        *pSize = i*(sqlite3_int64)pGroup->szChunk + sz;
       }
     }
   }

From 31b21295b0f291b2e4f37442b687672e1feffac3 Mon Sep 17 00:00:00 2001
From: dan <dan@noemail.net>
Date: Thu, 15 Dec 2011 11:45:19 +0000
Subject: [PATCH 02/10] Fix some problems with dropped error codes in
 multiplexOpen().

FossilOrigin-Name: 2d50f78188e3297e8cefdf73cff51fa0a3b36e65
---
 manifest             | 14 +++++++-------
 manifest.uuid        |  2 +-
 src/test_multiplex.c | 18 +++++++++++-------
 3 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/manifest b/manifest
index cd4f6d1738..33561aa1a4 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C In\sthe\smultiplexor,\sdo\snot\stry\sto\sdelete\soverflow\sfiles\sthat\sdo\snot\sexist.\nAnd\sassume\sall\sbut\sthe\slast\soverflow\sfile\sis\sthe\ssize\sof\sthe\schunk\ssize.
-D 2011-12-15T02:22:16.244
+C Fix\ssome\sproblems\swith\sdropped\serror\scodes\sin\smultiplexOpen().
+D 2011-12-15T11:45:19.350
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -214,7 +214,7 @@ F src/test_intarray.h 489edb9068bb926583445cb02589344961054207
 F src/test_journal.c 03313c693cca72959dcaaf79f8d76f21c01e19ff
 F src/test_loadext.c df586c27176e3c2cb2e099c78da67bf14379a56e
 F src/test_malloc.c 8d416f29ad8573f32601f6056c9d2b17472e9ad5
-F src/test_multiplex.c cee2474efe6ee92732e43184f62422bc17623d1f
+F src/test_multiplex.c 7e8d8303b8ba74ff50fbb40502522e576760266e
 F src/test_multiplex.h e99c571bc4968b7a9363b661481f3934bfead61d
 F src/test_mutex.c a6bd7b9cf6e19d989e31392b06ac8d189f0d573e
 F src/test_onefile.c 40cf9e212a377a6511469384a64b01e6e34b2eec
@@ -978,7 +978,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P 08c1dc517c1340737a55ad9012b7b06f72899c6f
-R 05ea69e1c214c57dec4ba569476ada26
-U drh
-Z 5b0957f1b7fd94c5b03cf783382a1410
+P a822a80d3cfe42b2fca6f8c9ff11762993114a27
+R 4637baef8720406f37351464996699d4
+U dan
+Z a1536baba57190ddd9d59e1c01fe9761
diff --git a/manifest.uuid b/manifest.uuid
index 18315cb8d5..b07b3ebcac 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-a822a80d3cfe42b2fca6f8c9ff11762993114a27
\ No newline at end of file
+2d50f78188e3297e8cefdf73cff51fa0a3b36e65
\ No newline at end of file
diff --git a/src/test_multiplex.c b/src/test_multiplex.c
index b9688e34df..f0d495f491 100644
--- a/src/test_multiplex.c
+++ b/src/test_multiplex.c
@@ -466,13 +466,15 @@ static int multiplexOpen(
     rc = multiplexSubFilename(pGroup, 1);
     if( rc==SQLITE_OK ){
       pSubOpen = multiplexSubOpen(pGroup, 0, &rc, pOutFlags);
+      assert( pSubOpen || rc!=SQLITE_OK );
     }
-    if( pSubOpen ){
-      int exists, rc2, rc3;
+    if( rc==SQLITE_OK ){
       sqlite3_int64 sz;
 
-      rc2 = pSubOpen->pMethods->xFileSize(pSubOpen, &sz);
-      if( rc2==SQLITE_OK && zName ){
+      rc = pSubOpen->pMethods->xFileSize(pSubOpen, &sz);
+      if( rc==SQLITE_OK && zName ){
+        int exists;
+
         /* If the first overflow file exists and if the size of the main file
         ** is different from the chunk size, that means the chunk size is set
         ** set incorrectly.  So fix it.
@@ -482,16 +484,18 @@ static int multiplexOpen(
         ** But we have no way of determining the intended chunk size, so 
         ** just disable the multiplexor all togethre.
         */
-        rc3 = pOrigVfs->xAccess(pOrigVfs, pGroup->aReal[1].z,
+        rc = pOrigVfs->xAccess(pOrigVfs, pGroup->aReal[1].z,
             SQLITE_ACCESS_EXISTS, &exists);
-        if( rc3==SQLITE_OK && exists && sz==(sz&0xffff0000) && sz>0
+        if( rc==SQLITE_OK && exists && sz==(sz&0xffff0000) && sz>0
             && sz!=pGroup->szChunk ){
           pGroup->szChunk = sz;
-        }else if( rc3==SQLITE_OK && !exists && sz>pGroup->szChunk ){
+        }else if( rc==SQLITE_OK && !exists && sz>pGroup->szChunk ){
           pGroup->bEnabled = 0;
         }
       }
+    }
 
+    if( rc==SQLITE_OK ){
       if( pSubOpen->pMethods->iVersion==1 ){
         pMultiplexOpen->base.pMethods = &gMultiplex.sIoMethodsV1;
       }else{

From 78c0eafb3535fd70d74b9753b4e52f7a6225b5a2 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Thu, 15 Dec 2011 13:29:12 +0000
Subject: [PATCH 03/10] Make sure the chunksize in test_multiplex does not
 cause the pending byte to fall near the end of a chunk.  Adjust the chunksize
 upward as necessary to prevent this.

FossilOrigin-Name: e05f8a2998f4f4cbdb65702baa65893c538b3d38
---
 manifest             | 14 +++++++-------
 manifest.uuid        |  2 +-
 src/test_multiplex.c | 10 ++++++++++
 3 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/manifest b/manifest
index 33561aa1a4..21cbee27f3 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\ssome\sproblems\swith\sdropped\serror\scodes\sin\smultiplexOpen().
-D 2011-12-15T11:45:19.350
+C Make\ssure\sthe\schunksize\sin\stest_multiplex\sdoes\snot\scause\sthe\spending\sbyte\nto\sfall\snear\sthe\send\sof\sa\schunk.\s\sAdjust\sthe\schunksize\supward\sas\snecessary\nto\sprevent\sthis.
+D 2011-12-15T13:29:12.575
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -214,7 +214,7 @@ F src/test_intarray.h 489edb9068bb926583445cb02589344961054207
 F src/test_journal.c 03313c693cca72959dcaaf79f8d76f21c01e19ff
 F src/test_loadext.c df586c27176e3c2cb2e099c78da67bf14379a56e
 F src/test_malloc.c 8d416f29ad8573f32601f6056c9d2b17472e9ad5
-F src/test_multiplex.c 7e8d8303b8ba74ff50fbb40502522e576760266e
+F src/test_multiplex.c 7b65eea8b390dd223bd6e0ba9d7879389bd075c0
 F src/test_multiplex.h e99c571bc4968b7a9363b661481f3934bfead61d
 F src/test_mutex.c a6bd7b9cf6e19d989e31392b06ac8d189f0d573e
 F src/test_onefile.c 40cf9e212a377a6511469384a64b01e6e34b2eec
@@ -978,7 +978,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P a822a80d3cfe42b2fca6f8c9ff11762993114a27
-R 4637baef8720406f37351464996699d4
-U dan
-Z a1536baba57190ddd9d59e1c01fe9761
+P 2d50f78188e3297e8cefdf73cff51fa0a3b36e65
+R db6d46332c6333123f8fa60ccb204a1d
+U drh
+Z f65d5d73aa828ce8ac2cca0eb8289aa5
diff --git a/manifest.uuid b/manifest.uuid
index b07b3ebcac..ce1d054b8f 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-2d50f78188e3297e8cefdf73cff51fa0a3b36e65
\ No newline at end of file
+e05f8a2998f4f4cbdb65702baa65893c538b3d38
\ No newline at end of file
diff --git a/src/test_multiplex.c b/src/test_multiplex.c
index f0d495f491..12e420fb5d 100644
--- a/src/test_multiplex.c
+++ b/src/test_multiplex.c
@@ -462,6 +462,16 @@ static int multiplexOpen(
       memcpy(pGroup->zName, zName, nName+1);
       pGroup->nName = nName;
     }
+    if( pGroup->bEnabled ){
+      /* Make sure that the chunksize is not such that the pending byte
+      ** falls at the end of a chunk.  A region of up to 64K following
+      ** the pending byte is never written, so if the pending byte occurs
+      ** near the end of a chunk, that chunk will be too small. */
+      extern int sqlite3PendingByte;
+      while( (sqlite3PendingByte % pGroup->szChunk)>=(pGroup->szChunk-65536) ){
+        pGroup->szChunk += 65536;
+      }
+    }
     pGroup->flags = flags;
     rc = multiplexSubFilename(pGroup, 1);
     if( rc==SQLITE_OK ){

From e712b5823e8c984491a8ac34e43fb5e50a995058 Mon Sep 17 00:00:00 2001
From: dan <dan@noemail.net>
Date: Thu, 15 Dec 2011 17:00:10 +0000
Subject: [PATCH 04/10] When deleting a file with the multiplexor VFS, also
 delete any overflow files that exist.

FossilOrigin-Name: 3af1feaa35d3fb2e7be550cd32a727001b874938
---
 manifest             |  14 ++---
 manifest.uuid        |   2 +-
 src/test_multiplex.c | 132 +++++++++++++++++++++++++++++++------------
 3 files changed, 105 insertions(+), 43 deletions(-)

diff --git a/manifest b/manifest
index 21cbee27f3..aec2b27521 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Make\ssure\sthe\schunksize\sin\stest_multiplex\sdoes\snot\scause\sthe\spending\sbyte\nto\sfall\snear\sthe\send\sof\sa\schunk.\s\sAdjust\sthe\schunksize\supward\sas\snecessary\nto\sprevent\sthis.
-D 2011-12-15T13:29:12.575
+C When\sdeleting\sa\sfile\swith\sthe\smultiplexor\sVFS,\salso\sdelete\sany\soverflow\sfiles\sthat\sexist.
+D 2011-12-15T17:00:10.854
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -214,7 +214,7 @@ F src/test_intarray.h 489edb9068bb926583445cb02589344961054207
 F src/test_journal.c 03313c693cca72959dcaaf79f8d76f21c01e19ff
 F src/test_loadext.c df586c27176e3c2cb2e099c78da67bf14379a56e
 F src/test_malloc.c 8d416f29ad8573f32601f6056c9d2b17472e9ad5
-F src/test_multiplex.c 7b65eea8b390dd223bd6e0ba9d7879389bd075c0
+F src/test_multiplex.c c87d27283e2f578c17a8db7a8cac095f576f4323
 F src/test_multiplex.h e99c571bc4968b7a9363b661481f3934bfead61d
 F src/test_mutex.c a6bd7b9cf6e19d989e31392b06ac8d189f0d573e
 F src/test_onefile.c 40cf9e212a377a6511469384a64b01e6e34b2eec
@@ -978,7 +978,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P 2d50f78188e3297e8cefdf73cff51fa0a3b36e65
-R db6d46332c6333123f8fa60ccb204a1d
-U drh
-Z f65d5d73aa828ce8ac2cca0eb8289aa5
+P e05f8a2998f4f4cbdb65702baa65893c538b3d38
+R 45b2cf463e6285a0d96697332c4d9aa9
+U dan
+Z 16b7798bc9bd7dfe8e0e630d52e6558b
diff --git a/manifest.uuid b/manifest.uuid
index ce1d054b8f..e4ed76872d 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-e05f8a2998f4f4cbdb65702baa65893c538b3d38
\ No newline at end of file
+3af1feaa35d3fb2e7be550cd32a727001b874938
\ No newline at end of file
diff --git a/src/test_multiplex.c b/src/test_multiplex.c
index 12e420fb5d..d844604ab5 100644
--- a/src/test_multiplex.c
+++ b/src/test_multiplex.c
@@ -216,6 +216,39 @@ static int multiplexStrlen30(const char *z){
   return 0x3fffffff & (int)(z2 - z);
 }
 
+/*
+** Generate the file-name for chunk iChunk of the group with base name
+** zBase. The file-name is written to buffer zOut before returning. Buffer
+** zOut must be allocated by the caller so that it is at least (nBase+4)
+** bytes in size, where nBase is the length of zBase, not including the
+** nul-terminator.
+*/
+static void multiplexFilename(
+  const char *zBase,              /* Filename for chunk 0 */
+  int nBase,                      /* Size of zBase in bytes (without \0) */
+  int flags,                      /* Flags used to open file */
+  int iChunk,                     /* Chunk to generate filename for */
+  char *zOut                      /* Buffer to write generated name to */
+){
+  memcpy(zOut, zBase, nBase+1);
+  if( iChunk!=0 && iChunk!=SQLITE_MULTIPLEX_JOURNAL_8_3_OFFSET ){
+    int n = nBase;
+#ifdef SQLITE_ENABLE_8_3_NAMES
+    int i;
+    for(i=n-1; i>0 && i>=n-4 && zOut[i]!='.'; i--){}
+    if( i>=n-4 ) n = i+1;
+    if( flags & SQLITE_OPEN_MAIN_JOURNAL ){
+      /* The extensions on overflow files for main databases are 001, 002,
+       ** 003 and so forth.  To avoid name collisions, add 400 to the 
+       ** extensions of journal files so that they are 401, 402, 403, ....
+       */
+      iChunk += SQLITE_MULTIPLEX_JOURNAL_8_3_OFFSET;
+    }
+#endif
+    sqlite3_snprintf(4,&zOut[n],"%03d",iChunk);
+  }
+}
+
 /* Compute the filename for the iChunk-th chunk
 */
 static int multiplexSubFilename(multiplexGroup *pGroup, int iChunk){
@@ -236,22 +269,7 @@ static int multiplexSubFilename(multiplexGroup *pGroup, int iChunk){
     if( z==0 ){
       return SQLITE_NOMEM;
     }
-    memcpy(z, pGroup->zName, n+1);
-    if( iChunk>0 ){
-#ifdef SQLITE_ENABLE_8_3_NAMES
-      int i;
-      for(i=n-1; i>0 && i>=n-4 && z[i]!='.'; i--){}
-      if( i>=n-4 ) n = i+1;
-      if( pGroup->flags & (SQLITE_OPEN_MAIN_JOURNAL|SQLITE_OPEN_TEMP_JOURNAL) ){
-        /* The extensions on overflow files for main databases are 001, 002,
-        ** 003 and so forth.  To avoid name collisions, add 400 to the 
-        ** extensions of journal files so that they are 401, 402, 403, ....
-        */
-        iChunk += SQLITE_MULTIPLEX_JOURNAL_8_3_OFFSET;
-      }
-#endif
-      sqlite3_snprintf(4,&z[n],"%03d",iChunk);
-    }
+    multiplexFilename(pGroup->zName, pGroup->nName, pGroup->flags, iChunk, z);
   }
   return SQLITE_OK;
 }
@@ -483,24 +501,43 @@ static int multiplexOpen(
 
       rc = pSubOpen->pMethods->xFileSize(pSubOpen, &sz);
       if( rc==SQLITE_OK && zName ){
-        int exists;
-
-        /* If the first overflow file exists and if the size of the main file
-        ** is different from the chunk size, that means the chunk size is set
-        ** set incorrectly.  So fix it.
-        **
-        ** Or, if the first overflow file does not exist and the main file is
-        ** larger than the chunk size, that means the chunk size is too small.
-        ** But we have no way of determining the intended chunk size, so 
-        ** just disable the multiplexor all togethre.
-        */
-        rc = pOrigVfs->xAccess(pOrigVfs, pGroup->aReal[1].z,
-            SQLITE_ACCESS_EXISTS, &exists);
-        if( rc==SQLITE_OK && exists && sz==(sz&0xffff0000) && sz>0
-            && sz!=pGroup->szChunk ){
-          pGroup->szChunk = sz;
-        }else if( rc==SQLITE_OK && !exists && sz>pGroup->szChunk ){
-          pGroup->bEnabled = 0;
+        int bExists;
+        if( sz==0 ){
+          if( flags & SQLITE_OPEN_MAIN_JOURNAL ){
+            /* If opening a main journal file and the first chunk is zero
+            ** bytes in size, delete any subsequent chunks from the 
+            ** file-system. */
+            int iChunk = 1;
+            do {
+              rc = pOrigVfs->xAccess(pOrigVfs, 
+                  pGroup->aReal[iChunk].z, SQLITE_ACCESS_EXISTS, &bExists
+              );
+              if( rc==SQLITE_OK && bExists ){
+                rc = pOrigVfs->xDelete(pOrigVfs, pGroup->aReal[iChunk].z, 0);
+                if( rc==SQLITE_OK ){
+                  rc = multiplexSubFilename(pGroup, ++iChunk);
+                }
+              }
+            }while( rc==SQLITE_OK && bExists );
+          }
+        }else{
+          /* If the first overflow file exists and if the size of the main file
+           ** is different from the chunk size, that means the chunk size is set
+           ** set incorrectly.  So fix it.
+           **
+           ** Or, if the first overflow file does not exist and the main file is
+           ** larger than the chunk size, that means the chunk size is too small.
+           ** But we have no way of determining the intended chunk size, so 
+           ** just disable the multiplexor all togethre.
+           */
+          rc = pOrigVfs->xAccess(pOrigVfs, pGroup->aReal[1].z,
+              SQLITE_ACCESS_EXISTS, &bExists);
+          if( rc==SQLITE_OK && bExists && sz==(sz&0xffff0000) && sz>0
+              && sz!=pGroup->szChunk ){
+            pGroup->szChunk = sz;
+          }else if( rc==SQLITE_OK && !bExists && sz>pGroup->szChunk ){
+            pGroup->bEnabled = 0;
+          }
         }
       }
     }
@@ -534,8 +571,33 @@ static int multiplexDelete(
   const char *zName,         /* Name of file to delete */
   int syncDir
 ){
+  int rc;
   sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */
-  return pOrigVfs->xDelete(pOrigVfs, zName, syncDir);
+  rc = pOrigVfs->xDelete(pOrigVfs, zName, syncDir);
+  if( rc==SQLITE_OK ){
+    /* If the main chunk was deleted successfully, also delete any subsequent
+    ** chunks - starting with the last (highest numbered). 
+    */
+    int nName = strlen(zName);
+    char *z;
+    z = sqlite3_malloc(nName + 4);
+    if( z==0 ){
+      rc = SQLITE_IOERR_NOMEM;
+    }else{
+      int iChunk = 0;
+      int bExists;
+      do{
+        multiplexFilename(zName, nName, SQLITE_OPEN_MAIN_JOURNAL, ++iChunk, z);
+        rc = pOrigVfs->xAccess(pOrigVfs, z, SQLITE_ACCESS_EXISTS, &bExists);
+      }while( rc==SQLITE_OK && bExists );
+      while( rc==SQLITE_OK && iChunk>1 ){
+        multiplexFilename(zName, nName, SQLITE_OPEN_MAIN_JOURNAL, --iChunk, z);
+        rc = pOrigVfs->xDelete(pOrigVfs, z, syncDir);
+      }
+    }
+    sqlite3_free(z);
+  }
+  return rc;
 }
 
 static int multiplexAccess(sqlite3_vfs *a, const char *b, int c, int *d){

From f580860f5196fc51fd5d9b6f42fe89e5b0573adc Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Fri, 16 Dec 2011 00:33:04 +0000
Subject: [PATCH 05/10] Make sure the antipenultimate character of
 master-journal filenames is a "9" in order to avoid collisions with other
 files in 8+3 filename mode.  Also, limit the number of attempts at finding a
 unique master-journal filename.

FossilOrigin-Name: 34a0483605d36e6cf03065ed0df33fb1f7c8a272
---
 manifest      | 16 ++++++++--------
 manifest.uuid |  2 +-
 src/util.c    |  1 +
 src/vdbeaux.c | 12 +++++++++++-
 4 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/manifest b/manifest
index aec2b27521..c6cfc989a6 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C When\sdeleting\sa\sfile\swith\sthe\smultiplexor\sVFS,\salso\sdelete\sany\soverflow\sfiles\sthat\sexist.
-D 2011-12-15T17:00:10.854
+C Make\ssure\sthe\santipenultimate\scharacter\sof\smaster-journal\sfilenames\sis\sa\s"9"\nin\sorder\sto\savoid\scollisions\swith\sother\sfiles\sin\s8+3\sfilename\smode.\s\sAlso,\nlimit\sthe\snumber\sof\sattempts\sat\sfinding\sa\sunique\smaster-journal\sfilename.
+D 2011-12-16T00:33:04.352
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -237,13 +237,13 @@ F src/tokenize.c c819d9f72168a035d545a5bdafe9b085b20df705
 F src/trigger.c 1cfb80e2290ef66ea89cb4e821caae65a02c0d56
 F src/update.c 25e046a8f69d5e557aabde2000487b8545509d8d
 F src/utf.c 890c67dcfcc7a74623c95baac7535aadfe265e84
-F src/util.c 01238e2b0f24a14779181dbf991fe02620a80e31
+F src/util.c 343508d359df65685b62e63964a40e7af4cfbe05
 F src/vacuum.c 0c0ba2242355c6048d65e2b333abe0f7c06348fa
 F src/vdbe.c a7ab9993ec5a4d9479dc99671faec061fbf9b889
 F src/vdbe.h f0725ee997db869ecae5bb70a71612aabeca7755
 F src/vdbeInt.h 9498fc98a2c9e349a4ef13455ff5a3e898f40176
 F src/vdbeapi.c 4dbba7f94f127f6ea8d2d0505ee1f98e5ffbf546
-F src/vdbeaux.c 45713a5f8f4f36195f503b30153ddef292323f88
+F src/vdbeaux.c 896ce3c48bf1bf27a1330589a20daa2db0222381
 F src/vdbeblob.c 32f2a4899d67f69634ea4dd93e3f651936d732cb
 F src/vdbemem.c 2fc78b3e0fabcc1eaa23cd79dd2e30e6dcfe1e56
 F src/vdbesort.c 468d43c057063e54da4f1988b38b4f46d60e7790
@@ -978,7 +978,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P e05f8a2998f4f4cbdb65702baa65893c538b3d38
-R 45b2cf463e6285a0d96697332c4d9aa9
-U dan
-Z 16b7798bc9bd7dfe8e0e630d52e6558b
+P 3af1feaa35d3fb2e7be550cd32a727001b874938
+R 398b3e3805c532cf24ac8d99750e0da2
+U drh
+Z ebbc2fb95389a75c4e570b61ca8c6d99
diff --git a/manifest.uuid b/manifest.uuid
index e4ed76872d..b3c3bab442 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-3af1feaa35d3fb2e7be550cd32a727001b874938
\ No newline at end of file
+34a0483605d36e6cf03065ed0df33fb1f7c8a272
\ No newline at end of file
diff --git a/src/util.c b/src/util.c
index ffbf7daadf..d27f6fdf26 100644
--- a/src/util.c
+++ b/src/util.c
@@ -1169,6 +1169,7 @@ int sqlite3AbsInt32(int x){
 **     test.db-journal    =>   test.nal
 **     test.db-wal        =>   test.wal
 **     test.db-shm        =>   test.shm
+**     test.db-mj7f3319fa =>   test.9fa
 */
 void sqlite3FileSuffix3(const char *zBaseFilename, char *z){
 #if SQLITE_ENABLE_8_3_NAMES<2
diff --git a/src/vdbeaux.c b/src/vdbeaux.c
index 7c69d28cf6..2e01c982e5 100644
--- a/src/vdbeaux.c
+++ b/src/vdbeaux.c
@@ -1824,16 +1824,26 @@ static int vdbeCommit(sqlite3 *db, Vdbe *p){
     sqlite3_file *pMaster = 0;
     i64 offset = 0;
     int res;
+    int retryCount = 0;
 
     /* Select a master journal file name */
     do {
       u32 iRandom;
+      if( retryCount++>100 ){
+        sqlite3_log(SQLITE_FULL, "cannot create a master journal filename");
+        rc = SQLITE_FULL;
+        break;
+      }
       sqlite3DbFree(db, zMaster);
       sqlite3_randomness(sizeof(iRandom), &iRandom);
-      zMaster = sqlite3MPrintf(db, "%s-mj%08X", zMainFile, iRandom&0x7fffffff);
+      zMaster = sqlite3MPrintf(db, "%s-mj%06X9%02X", zMainFile,
+                               (iRandom>>8)&0xffffff, iRandom&0xff);
       if( !zMaster ){
         return SQLITE_NOMEM;
       }
+      /* The antipenultimate character of the master journal name must
+      ** be "9" to avoid name collisions when using 8+3 filenames. */
+      assert( zMaster[strlen(zMaster)-3]=='9' );
       sqlite3FileSuffix3(zMainFile, zMaster);
       rc = sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS, &res);
     }while( rc==SQLITE_OK && res );

From 5c531a4aabce7f5a1f60ec87576f24092259a848 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Fri, 16 Dec 2011 01:21:31 +0000
Subject: [PATCH 06/10] A better solution to being unable to find a unique
 master-journal filename: just delete an existing master-journal and reuse it.

FossilOrigin-Name: 2685c2b949061f18bf6a4940eac8c8148873abb6
---
 manifest      | 12 ++++++------
 manifest.uuid |  2 +-
 src/vdbeaux.c | 15 +++++++--------
 3 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/manifest b/manifest
index c6cfc989a6..322d293528 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Make\ssure\sthe\santipenultimate\scharacter\sof\smaster-journal\sfilenames\sis\sa\s"9"\nin\sorder\sto\savoid\scollisions\swith\sother\sfiles\sin\s8+3\sfilename\smode.\s\sAlso,\nlimit\sthe\snumber\sof\sattempts\sat\sfinding\sa\sunique\smaster-journal\sfilename.
-D 2011-12-16T00:33:04.352
+C A\sbetter\ssolution\sto\sbeing\sunable\sto\sfind\sa\sunique\smaster-journal\sfilename:\njust\sdelete\san\sexisting\smaster-journal\sand\sreuse\sit.
+D 2011-12-16T01:21:31.882
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -243,7 +243,7 @@ F src/vdbe.c a7ab9993ec5a4d9479dc99671faec061fbf9b889
 F src/vdbe.h f0725ee997db869ecae5bb70a71612aabeca7755
 F src/vdbeInt.h 9498fc98a2c9e349a4ef13455ff5a3e898f40176
 F src/vdbeapi.c 4dbba7f94f127f6ea8d2d0505ee1f98e5ffbf546
-F src/vdbeaux.c 896ce3c48bf1bf27a1330589a20daa2db0222381
+F src/vdbeaux.c 7bae4d94d7e41e8005824a6d1da54b73d47f52b1
 F src/vdbeblob.c 32f2a4899d67f69634ea4dd93e3f651936d732cb
 F src/vdbemem.c 2fc78b3e0fabcc1eaa23cd79dd2e30e6dcfe1e56
 F src/vdbesort.c 468d43c057063e54da4f1988b38b4f46d60e7790
@@ -978,7 +978,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P 3af1feaa35d3fb2e7be550cd32a727001b874938
-R 398b3e3805c532cf24ac8d99750e0da2
+P 34a0483605d36e6cf03065ed0df33fb1f7c8a272
+R dac1ae186d64bf5089bb1df4a91a9793
 U drh
-Z ebbc2fb95389a75c4e570b61ca8c6d99
+Z cdecba57f424e5a33e7e2e3955b5bd95
diff --git a/manifest.uuid b/manifest.uuid
index b3c3bab442..6fdf08c334 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-34a0483605d36e6cf03065ed0df33fb1f7c8a272
\ No newline at end of file
+2685c2b949061f18bf6a4940eac8c8148873abb6
\ No newline at end of file
diff --git a/src/vdbeaux.c b/src/vdbeaux.c
index 2e01c982e5..6e183d0b8c 100644
--- a/src/vdbeaux.c
+++ b/src/vdbeaux.c
@@ -1825,25 +1825,24 @@ static int vdbeCommit(sqlite3 *db, Vdbe *p){
     i64 offset = 0;
     int res;
     int retryCount = 0;
+    int nMainFile;
 
     /* Select a master journal file name */
+    nMainFile = sqlite3Strlen30(zMainFile);
+    zMaster = sqlite3MPrintf(db, "%s-mjXXXXXX9XX", zMainFile);
+    if( zMaster==0 ) return SQLITE_NOMEM;
     do {
       u32 iRandom;
       if( retryCount++>100 ){
-        sqlite3_log(SQLITE_FULL, "cannot create a master journal filename");
-        rc = SQLITE_FULL;
+        sqlite3OsDelete(pVfs, zMaster, 0);
         break;
       }
-      sqlite3DbFree(db, zMaster);
       sqlite3_randomness(sizeof(iRandom), &iRandom);
-      zMaster = sqlite3MPrintf(db, "%s-mj%06X9%02X", zMainFile,
+      sqlite3_snprintf(13, &zMaster[nMainFile], "-mj%06X9%02X",
                                (iRandom>>8)&0xffffff, iRandom&0xff);
-      if( !zMaster ){
-        return SQLITE_NOMEM;
-      }
       /* The antipenultimate character of the master journal name must
       ** be "9" to avoid name collisions when using 8+3 filenames. */
-      assert( zMaster[strlen(zMaster)-3]=='9' );
+      assert( zMaster[sqlite3Strlen30(zMaster)-3]=='9' );
       sqlite3FileSuffix3(zMainFile, zMaster);
       rc = sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS, &res);
     }while( rc==SQLITE_OK && res );

From 38deeb9763133eea8ffbf1d7c1d3843bb8f2fc9e Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Fri, 16 Dec 2011 01:30:15 +0000
Subject: [PATCH 07/10] Call sqlite3_log() with an appropriate message if
 unable to find a unique master-journal filename.

FossilOrigin-Name: e9177f7d4ec19f0841d0613990d2fb5725700ba1
---
 manifest      | 12 ++++++------
 manifest.uuid |  2 +-
 src/vdbeaux.c |  1 +
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/manifest b/manifest
index 322d293528..0d3df0583b 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C A\sbetter\ssolution\sto\sbeing\sunable\sto\sfind\sa\sunique\smaster-journal\sfilename:\njust\sdelete\san\sexisting\smaster-journal\sand\sreuse\sit.
-D 2011-12-16T01:21:31.882
+C Call\ssqlite3_log()\swith\san\sappropriate\smessage\sif\sunable\sto\sfind\sa\sunique\nmaster-journal\sfilename.
+D 2011-12-16T01:30:15.388
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -243,7 +243,7 @@ F src/vdbe.c a7ab9993ec5a4d9479dc99671faec061fbf9b889
 F src/vdbe.h f0725ee997db869ecae5bb70a71612aabeca7755
 F src/vdbeInt.h 9498fc98a2c9e349a4ef13455ff5a3e898f40176
 F src/vdbeapi.c 4dbba7f94f127f6ea8d2d0505ee1f98e5ffbf546
-F src/vdbeaux.c 7bae4d94d7e41e8005824a6d1da54b73d47f52b1
+F src/vdbeaux.c 52ebf2a62d6b66ded536d0a2745f2236771097c7
 F src/vdbeblob.c 32f2a4899d67f69634ea4dd93e3f651936d732cb
 F src/vdbemem.c 2fc78b3e0fabcc1eaa23cd79dd2e30e6dcfe1e56
 F src/vdbesort.c 468d43c057063e54da4f1988b38b4f46d60e7790
@@ -978,7 +978,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P 34a0483605d36e6cf03065ed0df33fb1f7c8a272
-R dac1ae186d64bf5089bb1df4a91a9793
+P 2685c2b949061f18bf6a4940eac8c8148873abb6
+R 45a748a7c5e87682cd34056f04633da7
 U drh
-Z cdecba57f424e5a33e7e2e3955b5bd95
+Z 8c7f37ab067ed94fde60690f325712e2
diff --git a/manifest.uuid b/manifest.uuid
index 6fdf08c334..57de583d49 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-2685c2b949061f18bf6a4940eac8c8148873abb6
\ No newline at end of file
+e9177f7d4ec19f0841d0613990d2fb5725700ba1
\ No newline at end of file
diff --git a/src/vdbeaux.c b/src/vdbeaux.c
index 6e183d0b8c..bb1844dfb4 100644
--- a/src/vdbeaux.c
+++ b/src/vdbeaux.c
@@ -1834,6 +1834,7 @@ static int vdbeCommit(sqlite3 *db, Vdbe *p){
     do {
       u32 iRandom;
       if( retryCount++>100 ){
+        sqlite3_log(SQLITE_FULL, "cannot find unique master-journal");
         sqlite3OsDelete(pVfs, zMaster, 0);
         break;
       }

From e7d9f13d99667f89606a617eb9ffc01eb0fc8649 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Fri, 16 Dec 2011 04:57:32 +0000
Subject: [PATCH 08/10] The xTruncate method for the multiplexor now changes
 surplus overflow files to zero-length by default.  Or if the "truncate" query
 parameter is used, it actually deletes the surplus overflow files.  This
 allows VACUUM to shrink the database again.

FossilOrigin-Name: 5aefef04d6cc3b734c3f05e036b3869a52248f4d
---
 manifest             |  12 ++--
 manifest.uuid        |   2 +-
 src/test_multiplex.c | 168 ++++++++++++++++++++++++-------------------
 3 files changed, 103 insertions(+), 79 deletions(-)

diff --git a/manifest b/manifest
index 0d3df0583b..a12b10d33a 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Call\ssqlite3_log()\swith\san\sappropriate\smessage\sif\sunable\sto\sfind\sa\sunique\nmaster-journal\sfilename.
-D 2011-12-16T01:30:15.388
+C The\sxTruncate\smethod\sfor\sthe\smultiplexor\snow\schanges\ssurplus\soverflow\nfiles\sto\szero-length\sby\sdefault.\s\sOr\sif\sthe\s"truncate"\squery\sparameter\s\nis\sused,\sit\sactually\sdeletes\sthe\ssurplus\soverflow\sfiles.\s\sThis\sallows\nVACUUM\sto\sshrink\sthe\sdatabase\sagain.
+D 2011-12-16T04:57:32.390
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -214,7 +214,7 @@ F src/test_intarray.h 489edb9068bb926583445cb02589344961054207
 F src/test_journal.c 03313c693cca72959dcaaf79f8d76f21c01e19ff
 F src/test_loadext.c df586c27176e3c2cb2e099c78da67bf14379a56e
 F src/test_malloc.c 8d416f29ad8573f32601f6056c9d2b17472e9ad5
-F src/test_multiplex.c c87d27283e2f578c17a8db7a8cac095f576f4323
+F src/test_multiplex.c 993f930c9c8e1aa0f4fe7b5a74c9a60fbf3447e4
 F src/test_multiplex.h e99c571bc4968b7a9363b661481f3934bfead61d
 F src/test_mutex.c a6bd7b9cf6e19d989e31392b06ac8d189f0d573e
 F src/test_onefile.c 40cf9e212a377a6511469384a64b01e6e34b2eec
@@ -978,7 +978,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P 2685c2b949061f18bf6a4940eac8c8148873abb6
-R 45a748a7c5e87682cd34056f04633da7
+P e9177f7d4ec19f0841d0613990d2fb5725700ba1
+R c09d355f93cdab856d4274295151320d
 U drh
-Z 8c7f37ab067ed94fde60690f325712e2
+Z 4efbc5088c9568c2b7090122e09b39c8
diff --git a/manifest.uuid b/manifest.uuid
index 57de583d49..4852f04967 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-e9177f7d4ec19f0841d0613990d2fb5725700ba1
\ No newline at end of file
+5aefef04d6cc3b734c3f05e036b3869a52248f4d
\ No newline at end of file
diff --git a/src/test_multiplex.c b/src/test_multiplex.c
index d844604ab5..f01a7f585b 100644
--- a/src/test_multiplex.c
+++ b/src/test_multiplex.c
@@ -133,7 +133,8 @@ struct multiplexGroup {
   int nName;                       /* Length of base filename */
   int flags;                       /* Flags used for original opening */
   unsigned int szChunk;            /* Chunk size used for this group */
-  int bEnabled;                    /* TRUE to use Multiplex VFS for this file */
+  unsigned char bEnabled;          /* TRUE to use Multiplex VFS for this file */
+  unsigned char bTruncate;         /* TRUE to enable truncation of databases */
   multiplexGroup *pNext, *pPrev;   /* Doubly linked list of all group objects */
 };
 
@@ -276,12 +277,17 @@ static int multiplexSubFilename(multiplexGroup *pGroup, int iChunk){
 
 /* Translate an sqlite3_file* that is really a multiplexGroup* into
 ** the sqlite3_file* for the underlying original VFS.
+**
+** For chunk 0, the pGroup->flags determines whether or not a new file
+** is created if it does not already exist.  For chunks 1 and higher, the
+** file is created only if createFlag is 1.
 */
 static sqlite3_file *multiplexSubOpen(
-  multiplexGroup *pGroup,
-  int iChunk,
-  int *rc,
-  int *pOutFlags
+  multiplexGroup *pGroup,    /* The multiplexor group */
+  int iChunk,                /* Which chunk to open.  0==original file */
+  int *rc,                   /* Result code in and out */
+  int *pOutFlags,            /* Output flags */
+  int createFlag             /* True to create if iChunk>0 */
 ){
   sqlite3_file *pSubOpen = 0;
   sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;        /* Real VFS */
@@ -299,15 +305,28 @@ static sqlite3_file *multiplexSubOpen(
 
   *rc = multiplexSubFilename(pGroup, iChunk);
   if( (*rc)==SQLITE_OK && (pSubOpen = pGroup->aReal[iChunk].p)==0 ){
+    int flags, rc2, bExists;
+    if( iChunk==0 ) createFlag = (pGroup->flags & SQLITE_OPEN_CREATE)!=0;
+    flags = pGroup->flags;
+    if( createFlag ){
+      flags |= SQLITE_OPEN_CREATE;
+    }else if( pGroup->aReal[iChunk].z==0 ){
+      return 0;
+    }else{
+      *rc = pOrigVfs->xAccess(pOrigVfs, pGroup->aReal[iChunk].z,
+                              SQLITE_ACCESS_EXISTS, &bExists);
+      if( *rc || !bExists ) return 0;
+      flags &= ~SQLITE_OPEN_CREATE;
+    }
     pSubOpen = sqlite3_malloc( pOrigVfs->szOsFile );
     if( pSubOpen==0 ){
       *rc = SQLITE_NOMEM;
       return 0;
     }
     pGroup->aReal[iChunk].p = pSubOpen;
-    *rc = pOrigVfs->xOpen(pOrigVfs, pGroup->aReal[iChunk].z, pSubOpen,
-                          pGroup->flags, pOutFlags);
-    if( *rc!=SQLITE_OK ){
+    rc2 = pOrigVfs->xOpen(pOrigVfs, pGroup->aReal[iChunk].z, pSubOpen,
+                          flags, pOutFlags);
+    if( rc2!=SQLITE_OK ){
       sqlite3_free(pSubOpen);
       pGroup->aReal[iChunk].p = 0;
       return 0;
@@ -316,6 +335,25 @@ static sqlite3_file *multiplexSubOpen(
   return pSubOpen;
 }
 
+/*
+** Return the size, in bytes, of chunk number iChunk.  If that chunk
+** does not exist, then return 0.  This function does not distingish between
+** non-existant files and zero-length files.
+*/
+static sqlite3_int64 multiplexSubSize(
+  multiplexGroup *pGroup,    /* The multiplexor group */
+  int iChunk,                /* Which chunk to open.  0==original file */
+  int *rc                    /* Result code in and out */
+){
+  sqlite3_file *pSub;
+  sqlite3_int64 sz = 0;
+
+  pSub = multiplexSubOpen(pGroup, iChunk, rc, NULL, 0);
+  if( pSub==0 ) return 0;
+  *rc = pSub->pMethods->xFileSize(pSub, &sz);
+  return sz;
+}    
+
 /*
 ** This is the implementation of the multiplex_control() SQL function.
 */
@@ -455,6 +493,7 @@ static int multiplexOpen(
     memset(pGroup, 0, sz);
     pMultiplexOpen->pGroup = pGroup;
     pGroup->bEnabled = -1;
+    pGroup->bTruncate = (flags & SQLITE_OPEN_MAIN_DB)==0;
     pGroup->szChunk = SQLITE_MULTIPLEX_CHUNK_SIZE;
 
     if( zName ){
@@ -475,6 +514,7 @@ static int multiplexOpen(
             pGroup->bEnabled = 0;
           }
         }
+        if( sqlite3_uri_parameter(zName, "truncate") ) pGroup->bTruncate = 1;
       }
       pGroup->zName = p;
       memcpy(pGroup->zName, zName, nName+1);
@@ -493,8 +533,8 @@ static int multiplexOpen(
     pGroup->flags = flags;
     rc = multiplexSubFilename(pGroup, 1);
     if( rc==SQLITE_OK ){
-      pSubOpen = multiplexSubOpen(pGroup, 0, &rc, pOutFlags);
-      assert( pSubOpen || rc!=SQLITE_OK );
+      pSubOpen = multiplexSubOpen(pGroup, 0, &rc, pOutFlags, 0);
+      if( pSubOpen==0 && rc==SQLITE_OK ) rc = SQLITE_CANTOPEN;
     }
     if( rc==SQLITE_OK ){
       sqlite3_int64 sz;
@@ -522,17 +562,18 @@ static int multiplexOpen(
           }
         }else{
           /* If the first overflow file exists and if the size of the main file
-           ** is different from the chunk size, that means the chunk size is set
-           ** set incorrectly.  So fix it.
-           **
-           ** Or, if the first overflow file does not exist and the main file is
-           ** larger than the chunk size, that means the chunk size is too small.
-           ** But we have no way of determining the intended chunk size, so 
-           ** just disable the multiplexor all togethre.
-           */
+          ** is different from the chunk size, that means the chunk size is set
+          ** set incorrectly.  So fix it.
+          **
+          ** Or, if the first overflow file does not exist and the main file is
+          ** larger than the chunk size, that means the chunk size is too small.
+          ** But we have no way of determining the intended chunk size, so 
+          ** just disable the multiplexor all togethre.
+          */
           rc = pOrigVfs->xAccess(pOrigVfs, pGroup->aReal[1].z,
               SQLITE_ACCESS_EXISTS, &bExists);
-          if( rc==SQLITE_OK && bExists && sz==(sz&0xffff0000) && sz>0
+          bExists = multiplexSubSize(pGroup, 1, &rc)>0;
+          if( rc==SQLITE_OK && bExists  && sz==(sz&0xffff0000) && sz>0
               && sz!=pGroup->szChunk ){
             pGroup->szChunk = sz;
           }else if( rc==SQLITE_OK && !bExists && sz>pGroup->szChunk ){
@@ -674,7 +715,7 @@ static int multiplexRead(
   int rc = SQLITE_OK;
   multiplexEnter();
   if( !pGroup->bEnabled ){
-    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL);
+    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0);
     if( pSubOpen==0 ){
       rc = SQLITE_IOERR_READ;
     }else{
@@ -683,7 +724,7 @@ static int multiplexRead(
   }else{
     while( iAmt > 0 ){
       int i = (int)(iOfst / pGroup->szChunk);
-      sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, i, &rc, NULL);
+      sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, i, &rc, NULL, 1);
       if( pSubOpen ){
         int extra = ((int)(iOfst % pGroup->szChunk) + iAmt) - pGroup->szChunk;
         if( extra<0 ) extra = 0;
@@ -719,7 +760,7 @@ static int multiplexWrite(
   int rc = SQLITE_OK;
   multiplexEnter();
   if( !pGroup->bEnabled ){
-    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL);
+    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0);
     if( pSubOpen==0 ){
       rc = SQLITE_IOERR_WRITE;
     }else{
@@ -728,7 +769,7 @@ static int multiplexWrite(
   }else{
     while( rc==SQLITE_OK && iAmt>0 ){
       int i = (int)(iOfst / pGroup->szChunk);
-      sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, i, &rc, NULL);
+      sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, i, &rc, NULL, 1);
       if( pSubOpen ){
         int extra = ((int)(iOfst % pGroup->szChunk) + iAmt) -
                     pGroup->szChunk;
@@ -756,28 +797,35 @@ static int multiplexTruncate(sqlite3_file *pConn, sqlite3_int64 size){
   int rc = SQLITE_OK;
   multiplexEnter();
   if( !pGroup->bEnabled ){
-    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL);
+    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0);
     if( pSubOpen==0 ){
       rc = SQLITE_IOERR_TRUNCATE;
     }else{
       rc = pSubOpen->pMethods->xTruncate(pSubOpen, size);
     }
-  }else if( (pGroup->flags & SQLITE_OPEN_MAIN_DB)==0 ){
-    int rc2;
+  }else{
     int i;
+    int iBaseGroup = (int)(size / pGroup->szChunk);
     sqlite3_file *pSubOpen;
     sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */
     /* delete the chunks above the truncate limit */
-    for(i=(int)(size / pGroup->szChunk)+1; i<pGroup->nReal; i++){
-      multiplexSubClose(pGroup, i, pOrigVfs);
+    for(i = pGroup->nReal-1; i>iBaseGroup && rc==SQLITE_OK; i--){
+      if( pGroup->bTruncate ){
+        multiplexSubClose(pGroup, i, pOrigVfs);
+      }else{
+        pSubOpen = multiplexSubOpen(pGroup, i, &rc, 0, 0);
+        if( pSubOpen ){
+          rc = pSubOpen->pMethods->xTruncate(pSubOpen, 0);
+        }
+      }
     }
-    pSubOpen = multiplexSubOpen(pGroup, (int)(size/pGroup->szChunk), &rc2,0);
-    if( pSubOpen ){
-      rc2 = pSubOpen->pMethods->xTruncate(pSubOpen, size % pGroup->szChunk);
-      if( rc2!=SQLITE_OK ) rc = rc2;
-    }else{
-      rc = SQLITE_IOERR_TRUNCATE;
+    if( rc==SQLITE_OK ){
+      pSubOpen = multiplexSubOpen(pGroup, iBaseGroup, &rc, 0, 0);
+      if( pSubOpen ){
+        rc = pSubOpen->pMethods->xTruncate(pSubOpen, size % pGroup->szChunk);
+      }
     }
+    if( rc ) rc = SQLITE_IOERR_TRUNCATE;
   }
   multiplexLeave();
   return rc;
@@ -812,42 +860,18 @@ static int multiplexFileSize(sqlite3_file *pConn, sqlite3_int64 *pSize){
   int i;
   multiplexEnter();
   if( !pGroup->bEnabled ){
-    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL);
+    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0);
     if( pSubOpen==0 ){
       rc = SQLITE_IOERR_FSTAT;
     }else{
       rc = pSubOpen->pMethods->xFileSize(pSubOpen, pSize);
     }
   }else{
-    sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;
     *pSize = 0;
     for(i=0; rc==SQLITE_OK; i++){
-      sqlite3_file *pSubOpen = 0;
-      int exists = 0;
-      rc = multiplexSubFilename(pGroup, i);
-      if( rc!=SQLITE_OK ) break;
-      if( pGroup->nReal>i && pGroup->aReal[i].p!=0 ){
-        exists = 1;
-      }else if( (pGroup->flags & SQLITE_OPEN_DELETEONCLOSE)==0 ){
-        const char *zReal = pGroup->aReal[i].z;
-        rc = pOrigVfs->xAccess(pOrigVfs, zReal, SQLITE_ACCESS_EXISTS, &exists);
-      }
-      if( exists==0 ){
-        /* stop at first "gap" or IO error. */
-        break;
-      }
-      if( rc==SQLITE_OK ){
-        pSubOpen = multiplexSubOpen(pGroup, i, &rc, NULL);
-      }
-      assert( pSubOpen || rc!=SQLITE_OK );
-      if( rc==SQLITE_OK ){
-        sqlite3_int64 sz = 0;
-        rc = pSubOpen->pMethods->xFileSize(pSubOpen, &sz);
-        if( rc==SQLITE_OK && sz>pGroup->szChunk ){
-          rc = SQLITE_IOERR_FSTAT;
-        }
-        *pSize = i*(sqlite3_int64)pGroup->szChunk + sz;
-      }
+      sqlite3_int64 sz = multiplexSubSize(pGroup, i, &rc);
+      if( sz==0 ) break;
+      *pSize = i*(sqlite3_int64)pGroup->szChunk + sz;
     }
   }
   multiplexLeave();
@@ -859,7 +883,7 @@ static int multiplexFileSize(sqlite3_file *pConn, sqlite3_int64 *pSize){
 static int multiplexLock(sqlite3_file *pConn, int lock){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0);
   if( pSubOpen ){
     return pSubOpen->pMethods->xLock(pSubOpen, lock);
   }
@@ -871,7 +895,7 @@ static int multiplexLock(sqlite3_file *pConn, int lock){
 static int multiplexUnlock(sqlite3_file *pConn, int lock){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0);
   if( pSubOpen ){
     return pSubOpen->pMethods->xUnlock(pSubOpen, lock);
   }
@@ -883,7 +907,7 @@ static int multiplexUnlock(sqlite3_file *pConn, int lock){
 static int multiplexCheckReservedLock(sqlite3_file *pConn, int *pResOut){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0);
   if( pSubOpen ){
     return pSubOpen->pMethods->xCheckReservedLock(pSubOpen, pResOut);
   }
@@ -931,7 +955,7 @@ static int multiplexFileControl(sqlite3_file *pConn, int op, void *pArg){
       rc = SQLITE_OK;
       break;
     default:
-      pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL);
+      pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0);
       if( pSubOpen ){
         rc = pSubOpen->pMethods->xFileControl(pSubOpen, op, pArg);
         if( op==SQLITE_FCNTL_VFSNAME && rc==SQLITE_OK ){
@@ -948,7 +972,7 @@ static int multiplexFileControl(sqlite3_file *pConn, int op, void *pArg){
 static int multiplexSectorSize(sqlite3_file *pConn){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0);
   if( pSubOpen && pSubOpen->pMethods->xSectorSize ){
     return pSubOpen->pMethods->xSectorSize(pSubOpen);
   }
@@ -960,7 +984,7 @@ static int multiplexSectorSize(sqlite3_file *pConn){
 static int multiplexDeviceCharacteristics(sqlite3_file *pConn){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0);
   if( pSubOpen ){
     return pSubOpen->pMethods->xDeviceCharacteristics(pSubOpen);
   }
@@ -978,7 +1002,7 @@ static int multiplexShmMap(
 ){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0);
   if( pSubOpen ){
     return pSubOpen->pMethods->xShmMap(pSubOpen, iRegion, szRegion, bExtend,pp);
   }
@@ -995,7 +1019,7 @@ static int multiplexShmLock(
 ){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0);
   if( pSubOpen ){
     return pSubOpen->pMethods->xShmLock(pSubOpen, ofst, n, flags);
   }
@@ -1007,7 +1031,7 @@ static int multiplexShmLock(
 static void multiplexShmBarrier(sqlite3_file *pConn){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0);
   if( pSubOpen ){
     pSubOpen->pMethods->xShmBarrier(pSubOpen);
   }
@@ -1018,7 +1042,7 @@ static void multiplexShmBarrier(sqlite3_file *pConn){
 static int multiplexShmUnmap(sqlite3_file *pConn, int deleteFlag){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0);
   if( pSubOpen ){
     return pSubOpen->pMethods->xShmUnmap(pSubOpen, deleteFlag);
   }

From 06999667980faaf686d7232e7d97bf1cf4907849 Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Fri, 16 Dec 2011 05:09:46 +0000
Subject: [PATCH 09/10] Fix a potential infinite loop (inserted by the previous
 check-in) on the multiplexWrite() method of the multiplexor.

FossilOrigin-Name: 022bf427c2edfe494ec7c222f436953ff56574a6
---
 manifest             | 12 ++++++------
 manifest.uuid        |  2 +-
 src/test_multiplex.c |  6 +++---
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/manifest b/manifest
index a12b10d33a..88df5c4fc4 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C The\sxTruncate\smethod\sfor\sthe\smultiplexor\snow\schanges\ssurplus\soverflow\nfiles\sto\szero-length\sby\sdefault.\s\sOr\sif\sthe\s"truncate"\squery\sparameter\s\nis\sused,\sit\sactually\sdeletes\sthe\ssurplus\soverflow\sfiles.\s\sThis\sallows\nVACUUM\sto\sshrink\sthe\sdatabase\sagain.
-D 2011-12-16T04:57:32.390
+C Fix\sa\spotential\sinfinite\sloop\s(inserted\sby\sthe\sprevious\scheck-in)\non\sthe\smultiplexWrite()\smethod\sof\sthe\smultiplexor.
+D 2011-12-16T05:09:46.415
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -214,7 +214,7 @@ F src/test_intarray.h 489edb9068bb926583445cb02589344961054207
 F src/test_journal.c 03313c693cca72959dcaaf79f8d76f21c01e19ff
 F src/test_loadext.c df586c27176e3c2cb2e099c78da67bf14379a56e
 F src/test_malloc.c 8d416f29ad8573f32601f6056c9d2b17472e9ad5
-F src/test_multiplex.c 993f930c9c8e1aa0f4fe7b5a74c9a60fbf3447e4
+F src/test_multiplex.c ccc5f2feae52c4fbef1a88205667a6bcf2078844
 F src/test_multiplex.h e99c571bc4968b7a9363b661481f3934bfead61d
 F src/test_mutex.c a6bd7b9cf6e19d989e31392b06ac8d189f0d573e
 F src/test_onefile.c 40cf9e212a377a6511469384a64b01e6e34b2eec
@@ -978,7 +978,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P e9177f7d4ec19f0841d0613990d2fb5725700ba1
-R c09d355f93cdab856d4274295151320d
+P 5aefef04d6cc3b734c3f05e036b3869a52248f4d
+R 8d7b158bf3a519193898c5ead6ba7790
 U drh
-Z 4efbc5088c9568c2b7090122e09b39c8
+Z d8c8d1df41588adf9be8799f58ddd721
diff --git a/manifest.uuid b/manifest.uuid
index 4852f04967..8cbc3f560c 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-5aefef04d6cc3b734c3f05e036b3869a52248f4d
\ No newline at end of file
+022bf427c2edfe494ec7c222f436953ff56574a6
\ No newline at end of file
diff --git a/src/test_multiplex.c b/src/test_multiplex.c
index f01a7f585b..47d553cc27 100644
--- a/src/test_multiplex.c
+++ b/src/test_multiplex.c
@@ -305,7 +305,7 @@ static sqlite3_file *multiplexSubOpen(
 
   *rc = multiplexSubFilename(pGroup, iChunk);
   if( (*rc)==SQLITE_OK && (pSubOpen = pGroup->aReal[iChunk].p)==0 ){
-    int flags, rc2, bExists;
+    int flags, bExists;
     if( iChunk==0 ) createFlag = (pGroup->flags & SQLITE_OPEN_CREATE)!=0;
     flags = pGroup->flags;
     if( createFlag ){
@@ -324,9 +324,9 @@ static sqlite3_file *multiplexSubOpen(
       return 0;
     }
     pGroup->aReal[iChunk].p = pSubOpen;
-    rc2 = pOrigVfs->xOpen(pOrigVfs, pGroup->aReal[iChunk].z, pSubOpen,
+    *rc = pOrigVfs->xOpen(pOrigVfs, pGroup->aReal[iChunk].z, pSubOpen,
                           flags, pOutFlags);
-    if( rc2!=SQLITE_OK ){
+    if( (*rc)!=SQLITE_OK ){
       sqlite3_free(pSubOpen);
       pGroup->aReal[iChunk].p = 0;
       return 0;

From 8c24a369a5e5efab956a7dac56083ecd0fdd4e6b Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Fri, 16 Dec 2011 05:50:39 +0000
Subject: [PATCH 10/10] Tweaks to the way multiplexSubOpen() works, for
 backwards compatibility.

FossilOrigin-Name: bb40338887c912be70cb6fe3b760d87c14bb88a5
---
 manifest             | 12 ++++++------
 manifest.uuid        |  2 +-
 src/test_multiplex.c |  6 ++++--
 3 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/manifest b/manifest
index 88df5c4fc4..1257f0f4ca 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sa\spotential\sinfinite\sloop\s(inserted\sby\sthe\sprevious\scheck-in)\non\sthe\smultiplexWrite()\smethod\sof\sthe\smultiplexor.
-D 2011-12-16T05:09:46.415
+C Tweaks\sto\sthe\sway\smultiplexSubOpen()\sworks,\sfor\sbackwards\scompatibility.
+D 2011-12-16T05:50:39.331
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5b4a3e12a850b021547e43daf886b25133b44c07
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -214,7 +214,7 @@ F src/test_intarray.h 489edb9068bb926583445cb02589344961054207
 F src/test_journal.c 03313c693cca72959dcaaf79f8d76f21c01e19ff
 F src/test_loadext.c df586c27176e3c2cb2e099c78da67bf14379a56e
 F src/test_malloc.c 8d416f29ad8573f32601f6056c9d2b17472e9ad5
-F src/test_multiplex.c ccc5f2feae52c4fbef1a88205667a6bcf2078844
+F src/test_multiplex.c 6e07b94e2fe430f7f4f0d7d67b5e58f504dea655
 F src/test_multiplex.h e99c571bc4968b7a9363b661481f3934bfead61d
 F src/test_mutex.c a6bd7b9cf6e19d989e31392b06ac8d189f0d573e
 F src/test_onefile.c 40cf9e212a377a6511469384a64b01e6e34b2eec
@@ -978,7 +978,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P 5aefef04d6cc3b734c3f05e036b3869a52248f4d
-R 8d7b158bf3a519193898c5ead6ba7790
+P 022bf427c2edfe494ec7c222f436953ff56574a6
+R 29ea54dcd671c93952fcbf93e86a1060
 U drh
-Z d8c8d1df41588adf9be8799f58ddd721
+Z b9fbbc1fe20301c015fc0588c12a3621
diff --git a/manifest.uuid b/manifest.uuid
index 8cbc3f560c..6edf6058c3 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-022bf427c2edfe494ec7c222f436953ff56574a6
\ No newline at end of file
+bb40338887c912be70cb6fe3b760d87c14bb88a5
\ No newline at end of file
diff --git a/src/test_multiplex.c b/src/test_multiplex.c
index 47d553cc27..25bfcdddd2 100644
--- a/src/test_multiplex.c
+++ b/src/test_multiplex.c
@@ -306,10 +306,12 @@ static sqlite3_file *multiplexSubOpen(
   *rc = multiplexSubFilename(pGroup, iChunk);
   if( (*rc)==SQLITE_OK && (pSubOpen = pGroup->aReal[iChunk].p)==0 ){
     int flags, bExists;
-    if( iChunk==0 ) createFlag = (pGroup->flags & SQLITE_OPEN_CREATE)!=0;
+    createFlag = (pGroup->flags & SQLITE_OPEN_CREATE)!=0;
     flags = pGroup->flags;
     if( createFlag ){
       flags |= SQLITE_OPEN_CREATE;
+    }else if( iChunk==0 ){
+      /* Fall through */
     }else if( pGroup->aReal[iChunk].z==0 ){
       return 0;
     }else{
@@ -320,7 +322,7 @@ static sqlite3_file *multiplexSubOpen(
     }
     pSubOpen = sqlite3_malloc( pOrigVfs->szOsFile );
     if( pSubOpen==0 ){
-      *rc = SQLITE_NOMEM;
+      *rc = SQLITE_IOERR_NOMEM;
       return 0;
     }
     pGroup->aReal[iChunk].p = pSubOpen;