When the multiplexor opens an auxiliary file, it now persists the name of that

file until it is closed, as it should.  Remove the limit on the number of
auxiliary files used by the multiplexor.

FossilOrigin-Name: 1ffa542bf913200a18ef77447aec4fc3ca1ed618

4 files changed, 177 insertions, 271 deletions

diff --git a/manifest b/manifest
index dc0a0982a..c0583658f 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Formatting\schanges\son\sthe\smultiplexor\scode\s-\smake\ssure\sno\slines\sexceed\s80\ncharacters.\s\sNo\slogical\schanges.
-D 2011-07-19T18:29:00.027
+C When\sthe\smultiplexor\sopens\san\sauxiliary\sfile,\sit\snow\spersists\sthe\sname\sof\sthat\nfile\suntil\sit\sis\sclosed,\sas\sit\sshould.\s\sRemove\sthe\slimit\son\sthe\snumber\sof\nauxiliary\sfiles\sused\sby\sthe\smultiplexor.
+D 2011-07-20T16:35:31.624
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in c1d7a7f4fd8da6b1815032efca950e3d5125407e
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -213,7 +213,7 @@ F src/test_intarray.h 489edb9068bb926583445cb02589344961054207
 F src/test_journal.c 03313c693cca72959dcaaf79f8d76f21c01e19ff
 F src/test_loadext.c df586c27176e3c2cb2e099c78da67bf14379a56e
 F src/test_malloc.c 7ca7be34e0e09ef0ed6619544552ed95732e41f6
-F src/test_multiplex.c d1b43de1209bd1bc207b694a738fdb84a162f65b
+F src/test_multiplex.c 282f315fd035c8d8342a4cc59748c60216b61fef
 F src/test_multiplex.h e99c571bc4968b7a9363b661481f3934bfead61d
 F src/test_mutex.c a6bd7b9cf6e19d989e31392b06ac8d189f0d573e
 F src/test_onefile.c 40cf9e212a377a6511469384a64b01e6e34b2eec
@@ -595,7 +595,7 @@ F test/misc5.test 9f9338f8211c7f5d1cbe16331fa65d019501aa50
 F test/misc6.test 953cc693924d88e6117aeba16f46f0bf5abede91
 F test/misc7.test 29032efcd3d826fbd409e2a7af873e7939f4a4e3
 F test/misuse.test 30b3a458e5a70c31e74c291937b6c82204c59f33
-F test/multiplex.test 555080c87abfc72ba68e2f3df01d4a9a7a4fdf58
+F test/multiplex.test 2256e90e8780de6eeafc07d4084427c3a97d3bcb
 F test/mutex1.test 78b2b9bb320e51d156c4efdb71b99b051e7a4b41
 F test/mutex2.test bfeaeac2e73095b2ac32285d2756e3a65e681660
 F test/nan.test dc212a22b36109fd1ae37154292444ef249c5ec2
@@ -952,7 +952,7 @@ F tool/symbols.sh caaf6ccc7300fd43353318b44524853e222557d5
 F tool/tostr.awk 11760e1b94a5d3dcd42378f3cc18544c06cfa576
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings.sh 2ebae31e1eb352696f3c2f7706a34c084b28c262
-P 4355bf2908b923e844907c1e3c09be3bf469f833
-R 33ae39ed3129fdb3c8dbf2c830ddcfd5
+P ed5f0aad6b21066bacd01521e82c22e96991f400
+R e63c3d9c3ff7ac85b18419c4f45127d4
 U drh
-Z 60f009445613def050e13415b0c93faf
+Z 1541751b97b37082064c8e76500e9b76
diff --git a/manifest.uuid b/manifest.uuid
index a91085ca7..04e86b35f 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-ed5f0aad6b21066bacd01521e82c22e96991f400
\ No newline at end of file
+1ffa542bf913200a18ef77447aec4fc3ca1ed618
\ No newline at end of file
diff --git a/src/test_multiplex.c b/src/test_multiplex.c
index 2203c60b5..b6fe9e8b6 100644
--- a/src/test_multiplex.c
+++ b/src/test_multiplex.c
@@ -126,13 +126,15 @@ typedef struct multiplexConn multiplexConn;
 ** group.
 */
 struct multiplexGroup {
-  sqlite3_file **pReal;            /* Handles to each chunk */
-  char *bOpen;                     /* array of bools - 0 if chunk not opened */
+  struct multiplexReal {           /* For each chunk */
+    sqlite3_file *p;                  /* Handle for the chunk */
+    char *z;                          /* Name of this chunk */
+  } *aReal;                        /* list of all chunks */
+  int nReal;                       /* Number of chunks */
   char *zName;                     /* Base filename of this group */
   int nName;                       /* Length of base filename */
   int flags;                       /* Flags used for original opening */
   int nChunkSize;                  /* Chunk size used for this group */
-  int nMaxChunks;                  /* Max number of chunks for this group */
   int bEnabled;                    /* TRUE to use Multiplex VFS for this file */
   multiplexGroup *pNext, *pPrev;   /* Doubly linked list of all group objects */
 };
@@ -191,12 +193,6 @@ static struct {
   /* List of multiplexGroup objects.
   */
   multiplexGroup *pGroups;
-
-  /* Storage for temp file names.  Allocated during 
-  ** initialization to the max pathname of the underlying VFS.
-  */
-  char *zName;
-
 } gMultiplex;
 
 /************************* Utility Routines *********************************/
@@ -287,45 +283,69 @@ static int multiplexGetTempname(sqlite3_vfs *pOrigVfs, int nBuf, char *zBuf){
   return rc;
 }
 
+/* Compute the filename for the iChunk-th chunk
+*/
+static int multiplexSubFilename(multiplexGroup *pGroup, int iChunk){
+  if( iChunk>=pGroup->nReal ){
+    struct multiplexReal *p;
+    p = sqlite3_realloc(pGroup->aReal, (iChunk+1)*sizeof(*p));
+    if( p==0 ){
+      return SQLITE_NOMEM;
+    }
+    memset(&p[pGroup->nReal], 0, sizeof(p[0])*(iChunk+1-pGroup->nReal));
+    pGroup->aReal = p;
+    pGroup->nReal = iChunk+1;
+  }
+  if( pGroup->aReal[iChunk].z==0 ){
+    char *z;
+    int n = pGroup->nName;
+    pGroup->aReal[iChunk].z = z = sqlite3_malloc( n+3 );
+    if( z==0 ){
+      return SQLITE_NOMEM;
+    }
+    memcpy(z, pGroup->zName, n+1);
+    if( iChunk>0 ){
+#ifdef SQLITE_ENABLE_8_3_NAMES
+      if( n>3 && z[n-3]=='.' ){
+        n--;
+      }else if( n>4 && z[n-4]=='.' ){
+        n -= 2;
+      }
+#endif
+      sqlite3_snprintf(3,&z[n],"%02d",iChunk);
+    }
+  }
+  return SQLITE_OK;
+}
+
 /* Translate an sqlite3_file* that is really a multiplexGroup* into
 ** the sqlite3_file* for the underlying original VFS.
 */
 static sqlite3_file *multiplexSubOpen(
-  multiplexConn *pConn,
+  multiplexGroup *pGroup,
   int iChunk,
   int *rc,
   int *pOutFlags
 ){
-  multiplexGroup *pGroup = pConn->pGroup;
+  sqlite3_file *pSubOpen = 0;
   sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;        /* Real VFS */
-  if( iChunk<pGroup->nMaxChunks ){
-    sqlite3_file *pSubOpen = pGroup->pReal[iChunk];   /* Real file descriptor */
-    if( !pGroup->bOpen[iChunk] ){
-      memcpy(gMultiplex.zName, pGroup->zName, pGroup->nName+1);
-      if( iChunk ){
-#ifdef SQLITE_MULTIPLEX_EXT_OVWR
-        sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1,
-             gMultiplex.zName+pGroup->nName-SQLITE_MULTIPLEX_EXT_SZ,
-             SQLITE_MULTIPLEX_EXT_FMT, iChunk);
-#else
-        sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1,
-             gMultiplex.zName+pGroup->nName,
-             SQLITE_MULTIPLEX_EXT_FMT, iChunk);
-#endif
-      }
-      *rc = pOrigVfs->xOpen(pOrigVfs, gMultiplex.zName, pSubOpen,
-                            pGroup->flags, pOutFlags);
-      if( *rc==SQLITE_OK ){
-        pGroup->bOpen[iChunk] = -1;
-        return pSubOpen;
-      }
-      return NULL;
+  *rc = multiplexSubFilename(pGroup, iChunk);
+  if( (*rc)==SQLITE_OK && (pSubOpen = pGroup->aReal[iChunk].p)==0 ){
+    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 ){
+      sqlite3_free(pSubOpen);
+      pGroup->aReal[iChunk].p = 0;
+      return 0;
     }
-    *rc = SQLITE_OK;
-    return pSubOpen;
   }
-  *rc = SQLITE_FULL;
-  return NULL;
+  return pSubOpen;
 }
 
 /*
@@ -384,6 +404,36 @@ static int multiplexFuncInit(
   return rc;
 }
 
+/*
+** Close a single sub-file in the connection group.
+*/
+static void multiplexSubClose(
+  multiplexGroup *pGroup,
+  int iChunk,
+  sqlite3_vfs *pOrigVfs
+){
+  sqlite3_file *pSubOpen = pGroup->aReal[iChunk].p;
+  if( pSubOpen ){
+    if( pOrigVfs ) pOrigVfs->xDelete(pOrigVfs, pGroup->aReal[iChunk].z, 0);
+    pSubOpen->pMethods->xClose(pSubOpen);
+    sqlite3_free(pGroup->aReal[iChunk].p);
+  }
+  sqlite3_free(pGroup->aReal[iChunk].z);
+  memset(&pGroup->aReal[iChunk], 0, sizeof(pGroup->aReal[iChunk]));
+}
+
+/*
+** Deallocate memory held by a multiplexGroup
+*/
+static void multiplexFreeComponents(multiplexGroup *pGroup){
+  int i;
+  for(i=0; i<pGroup->nReal; i++){ multiplexSubClose(pGroup, i, 0); }
+  sqlite3_free(pGroup->aReal);
+  pGroup->aReal = 0;
+  pGroup->nReal = 0;
+}
+
+
 /************************* VFS Method Wrappers *****************************/
 
 /*
@@ -406,10 +456,11 @@ static int multiplexOpen(
   sqlite3_file *pSubOpen;                        /* Real file descriptor */
   sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */
   int nName;
-  int i;
   int sz;
+  char *zToFree = 0;
 
   UNUSED_PARAMETER(pVfs);
+  memset(pConn, 0, pVfs->szOsFile);
 
   /* We need to create a group structure and manage
   ** access to this group of files.
@@ -423,28 +474,22 @@ static int multiplexOpen(
   ** it.
   */
   if( !zName ){
-    rc = multiplexGetTempname(pOrigVfs, pOrigVfs->mxPathname, gMultiplex.zName);
-    zName = gMultiplex.zName;
+    zName = zToFree = sqlite3_malloc( pOrigVfs->mxPathname + 10 );
+    if( zName==0 ){
+      rc = SQLITE_NOMEM;
+    }else{
+      rc = multiplexGetTempname(pOrigVfs, pOrigVfs->mxPathname, zToFree);
+    }
   }
 
   if( rc==SQLITE_OK ){
     /* allocate space for group */
     nName = multiplexStrlen30(zName);
     sz = sizeof(multiplexGroup)                             /* multiplexGroup */
-       + (sizeof(sqlite3_file *)*SQLITE_MULTIPLEX_MAX_CHUNKS)  /* pReal[] */
-       + (pOrigVfs->szOsFile*SQLITE_MULTIPLEX_MAX_CHUNKS)      /* *pReal */
-       + SQLITE_MULTIPLEX_MAX_CHUNKS                           /* bOpen[] */
-       + nName + 1;                                            /* zName */
-#ifndef SQLITE_MULTIPLEX_EXT_OVWR
-    sz += SQLITE_MULTIPLEX_EXT_SZ;
-    assert(nName+SQLITE_MULTIPLEX_EXT_SZ < pOrigVfs->mxPathname);
-#else
-    assert(nName >= SQLITE_MULTIPLEX_EXT_SZ);
-    assert(nName < pOrigVfs->mxPathname);
-#endif
+       + nName + 1;                                         /* zName */
     pGroup = sqlite3_malloc( sz );
     if( pGroup==0 ){
-      rc=SQLITE_NOMEM;
+      rc = SQLITE_NOMEM;
     }
   }
 
@@ -456,27 +501,19 @@ static int multiplexOpen(
     memset(pGroup, 0, sz);
     pGroup->bEnabled = -1;
     pGroup->nChunkSize = SQLITE_MULTIPLEX_CHUNK_SIZE;
-    zChunkSize = sqlite3_uri_parameter(zName, "chunksize");
-    if( zChunkSize ){
-      int n = atoi(zChunkSize);
-      if( n>0 ) pGroup->nChunkSize = (n+0xffff)&~0xffff;
-    }
-    pGroup->nMaxChunks = SQLITE_MULTIPLEX_MAX_CHUNKS;
-    pGroup->pReal = (sqlite3_file **)p;
-    p += (sizeof(sqlite3_file *)*pGroup->nMaxChunks);
-    for(i=0; i<pGroup->nMaxChunks; i++){
-      pGroup->pReal[i] = (sqlite3_file *)p;
-      p += pOrigVfs->szOsFile;
+    if( flags & SQLITE_OPEN_URI ){
+      zChunkSize = sqlite3_uri_parameter(zName, "chunksize");
+      if( zChunkSize ){
+        int n = atoi(zChunkSize);
+        if( n>0 ) pGroup->nChunkSize = (n+0xffff)&~0xffff;
+      }
     }
-    /* bOpen[] vals should all be zero from memset above */
-    pGroup->bOpen = p;
-    p += pGroup->nMaxChunks;
     pGroup->zName = p;
     /* save off base filename, name length, and original open flags  */
     memcpy(pGroup->zName, zName, nName+1);
     pGroup->nName = nName;
     pGroup->flags = flags;
-    pSubOpen = multiplexSubOpen(pMultiplexOpen, 0, &rc, pOutFlags);
+    pSubOpen = multiplexSubOpen(pGroup, 0, &rc, pOutFlags);
     if( pSubOpen ){
       /* if this file is already larger than chunk size, disable 
       ** the multiplex feature.
@@ -496,17 +533,18 @@ static int multiplexOpen(
       if( gMultiplex.pGroups ) gMultiplex.pGroups->pPrev = pGroup;
       gMultiplex.pGroups = pGroup;
     }else{
+      multiplexFreeComponents(pGroup);
       sqlite3_free(pGroup);
     }
   }
   multiplexLeave();
+  sqlite3_free(zToFree);
   return rc;
 }
 
 /*
 ** This is the xDelete method used for the "multiplex" VFS.
-** It attempts to delete the filename specified, as well
-** as additional files with the SQLITE_MULTIPLEX_EXT_FMT extension.
+** It attempts to delete the filename specified.
 */
 static int multiplexDelete(
   sqlite3_vfs *pVfs,         /* The multiplex VFS */
@@ -514,41 +552,7 @@ static int multiplexDelete(
   int syncDir
 ){
   sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */
-  int rc = SQLITE_OK;
-  int nName = multiplexStrlen30(zName);
-  int i;
-
-  UNUSED_PARAMETER(pVfs);
-
-  multiplexEnter();
-  memcpy(gMultiplex.zName, zName, nName+1);
-  for(i=0; i<SQLITE_MULTIPLEX_MAX_CHUNKS; i++){
-    int rc2;
-    int exists = 0;
-    if( i ){
-#ifdef SQLITE_MULTIPLEX_EXT_OVWR
-        sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
-            gMultiplex.zName+nName-SQLITE_MULTIPLEX_EXT_SZ, 
-            SQLITE_MULTIPLEX_EXT_FMT, i);
-#else
-        sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
-            gMultiplex.zName+nName, 
-            SQLITE_MULTIPLEX_EXT_FMT, i);
-#endif
-    }
-    rc2 = pOrigVfs->xAccess(pOrigVfs, gMultiplex.zName, 
-        SQLITE_ACCESS_EXISTS, &exists);
-    if( rc2==SQLITE_OK && exists ){
-      /* if it exists, delete it */
-      rc2 = pOrigVfs->xDelete(pOrigVfs, gMultiplex.zName, syncDir);
-      if( rc2!=SQLITE_OK ) rc = rc2;
-    }else{
-      /* stop at first "gap" */
-      break;
-    }
-  }
-  multiplexLeave();
-  return rc;
+  return pOrigVfs->xDelete(pOrigVfs, zName, syncDir);
 }
 
 static int multiplexAccess(sqlite3_vfs *a, const char *b, int c, int *d){
@@ -596,17 +600,8 @@ static int multiplexClose(sqlite3_file *pConn){
   multiplexConn *p = (multiplexConn*)pConn;
   multiplexGroup *pGroup = p->pGroup;
   int rc = SQLITE_OK;
-  int i;
   multiplexEnter();
-  /* close any open handles */
-  for(i=0; i<pGroup->nMaxChunks; i++){
-    if( pGroup->bOpen[i] ){
-      sqlite3_file *pSubOpen = pGroup->pReal[i];
-      int rc2 = pSubOpen->pMethods->xClose(pSubOpen);
-      if( rc2!=SQLITE_OK ) rc = rc2;
-      pGroup->bOpen[i] = 0;
-    }
-  }
+  multiplexFreeComponents(pGroup);
   /* remove from linked list */
   if( pGroup->pNext ) pGroup->pNext->pPrev = pGroup->pPrev;
   if( pGroup->pPrev ){
@@ -634,8 +629,8 @@ static int multiplexRead(
   int rc = SQLITE_OK;
   multiplexEnter();
   if( !pGroup->bEnabled ){
-    sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
-    if( !pSubOpen ){
+    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL);
+    if( pSubOpen==0 ){
       rc = SQLITE_IOERR_READ;
     }else{
       rc = pSubOpen->pMethods->xRead(pSubOpen, pBuf, iAmt, iOfst);
@@ -643,7 +638,7 @@ static int multiplexRead(
   }else{
     while( iAmt > 0 ){
       int i = (int)(iOfst / pGroup->nChunkSize);
-      sqlite3_file *pSubOpen = multiplexSubOpen(p, i, &rc, NULL);
+      sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, i, &rc, NULL);
       if( pSubOpen ){
         int extra = ((int)(iOfst % pGroup->nChunkSize) + iAmt) -
                                                         pGroup->nChunkSize;
@@ -680,7 +675,7 @@ static int multiplexWrite(
   int rc = SQLITE_OK;
   multiplexEnter();
   if( !pGroup->bEnabled ){
-    sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
+    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL);
     if( pSubOpen==0 ){
       rc = SQLITE_IOERR_WRITE;
     }else{
@@ -689,7 +684,7 @@ static int multiplexWrite(
   }else{
     while( iAmt > 0 ){
       int i = (int)(iOfst / pGroup->nChunkSize);
-      sqlite3_file *pSubOpen = multiplexSubOpen(p, i, &rc, NULL);
+      sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, i, &rc, NULL);
       if( pSubOpen ){
         int extra = ((int)(iOfst % pGroup->nChunkSize) + iAmt) -
                     pGroup->nChunkSize;
@@ -721,7 +716,7 @@ static int multiplexTruncate(sqlite3_file *pConn, sqlite3_int64 size){
   int rc = SQLITE_OK;
   multiplexEnter();
   if( !pGroup->bEnabled ){
-    sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
+    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL);
     if( pSubOpen==0 ){
       rc = SQLITE_IOERR_TRUNCATE;
     }else{
@@ -732,29 +727,11 @@ static int multiplexTruncate(sqlite3_file *pConn, sqlite3_int64 size){
     int i;
     sqlite3_file *pSubOpen;
     sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */
-    memcpy(gMultiplex.zName, pGroup->zName, pGroup->nName+1);
     /* delete the chunks above the truncate limit */
-    for(i=(int)(size / pGroup->nChunkSize)+1; i<pGroup->nMaxChunks; i++){
-      /* close any open chunks before deleting them */
-      if( pGroup->bOpen[i] ){
-        pSubOpen = pGroup->pReal[i];
-        rc2 = pSubOpen->pMethods->xClose(pSubOpen);
-        if( rc2!=SQLITE_OK ) rc = SQLITE_IOERR_TRUNCATE;
-        pGroup->bOpen[i] = 0;
-      }
-#ifdef SQLITE_MULTIPLEX_EXT_OVWR
-      sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
-          gMultiplex.zName+pGroup->nName-SQLITE_MULTIPLEX_EXT_SZ, 
-          SQLITE_MULTIPLEX_EXT_FMT, i);
-#else
-      sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
-          gMultiplex.zName+pGroup->nName, 
-          SQLITE_MULTIPLEX_EXT_FMT, i);
-#endif
-      rc2 = pOrigVfs->xDelete(pOrigVfs, gMultiplex.zName, 0);
-      if( rc2!=SQLITE_OK ) rc = SQLITE_IOERR_TRUNCATE;
+    for(i=(int)(size / pGroup->nChunkSize)+1; i<pGroup->nReal; i++){
+      multiplexSubClose(pGroup, i, pOrigVfs);
     }
-    pSubOpen = multiplexSubOpen(p, (int)(size/pGroup->nChunkSize), &rc2, NULL);
+    pSubOpen = multiplexSubOpen(pGroup, (int)(size/pGroup->nChunkSize), &rc2,0);
     if( pSubOpen ){
       rc2 = pSubOpen->pMethods->xTruncate(pSubOpen, size % pGroup->nChunkSize);
       if( rc2!=SQLITE_OK ) rc = rc2;
@@ -774,10 +751,9 @@ static int multiplexSync(sqlite3_file *pConn, int flags){
   int rc = SQLITE_OK;
   int i;
   multiplexEnter();
-  for(i=0; i<pGroup->nMaxChunks; i++){
-    /* if we don't have it open, we don't need to sync it */
-    if( pGroup->bOpen[i] ){
-      sqlite3_file *pSubOpen = pGroup->pReal[i];
+  for(i=0; i<pGroup->nReal; i++){
+    sqlite3_file *pSubOpen = pGroup->aReal[i].p;
+    if( pSubOpen ){
       int rc2 = pSubOpen->pMethods->xSync(pSubOpen, flags);
       if( rc2!=SQLITE_OK ) rc = rc2;
     }
@@ -797,7 +773,7 @@ static int multiplexFileSize(sqlite3_file *pConn, sqlite3_int64 *pSize){
   int i;
   multiplexEnter();
   if( !pGroup->bEnabled ){
-    sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
+    sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL);
     if( pSubOpen==0 ){
       rc = SQLITE_IOERR_FSTAT;
     }else{
@@ -805,35 +781,20 @@ static int multiplexFileSize(sqlite3_file *pConn, sqlite3_int64 *pSize){
     }
   }else{
     *pSize = 0;
-    for(i=0; i<pGroup->nMaxChunks; i++){
-      sqlite3_file *pSubOpen = NULL;
-      /* if not opened already, check to see if the chunk exists */
-      if( pGroup->bOpen[i] ){
-        pSubOpen = pGroup->pReal[i];
+    for(i=0; 1; i++){
+      sqlite3_file *pSubOpen = 0;
+      sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;
+      int exists = 0;
+      rc = multiplexSubFilename(pGroup, i);
+      if( rc ) break;
+      rc2 = pOrigVfs->xAccess(pOrigVfs, pGroup->aReal[i].z,
+          SQLITE_ACCESS_EXISTS, &exists);
+      if( rc2==SQLITE_OK && exists){
+        /* if it exists, open it */
+        pSubOpen = multiplexSubOpen(pGroup, i, &rc, NULL);
       }else{
-        sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */
-        int exists = 0;
-        memcpy(gMultiplex.zName, pGroup->zName, pGroup->nName+1);
-        if( i ){
-#ifdef SQLITE_MULTIPLEX_EXT_OVWR
-          sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
-              gMultiplex.zName+pGroup->nName-SQLITE_MULTIPLEX_EXT_SZ, 
-              SQLITE_MULTIPLEX_EXT_FMT, i);
-#else
-          sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
-              gMultiplex.zName+pGroup->nName, 
-              SQLITE_MULTIPLEX_EXT_FMT, i);
-#endif
-        }
-        rc2 = pOrigVfs->xAccess(pOrigVfs, gMultiplex.zName, 
-            SQLITE_ACCESS_EXISTS, &exists);
-        if( rc2==SQLITE_OK && exists){
-          /* if it exists, open it */
-          pSubOpen = multiplexSubOpen(p, i, &rc, NULL);
-        }else{
-          /* stop at first "gap" */
-          break;
-        }
+        /* stop at first "gap" */
+        break;
       }
       if( pSubOpen ){
         sqlite3_int64 sz;
@@ -860,7 +821,7 @@ 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, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
   if( pSubOpen ){
     return pSubOpen->pMethods->xLock(pSubOpen, lock);
   }
@@ -872,7 +833,7 @@ 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, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
   if( pSubOpen ){
     return pSubOpen->pMethods->xUnlock(pSubOpen, lock);
   }
@@ -884,7 +845,7 @@ 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, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
   if( pSubOpen ){
     return pSubOpen->pMethods->xCheckReservedLock(pSubOpen, pResOut);
   }
@@ -924,15 +885,7 @@ static int multiplexFileControl(sqlite3_file *pConn, int op, void *pArg){
       }
       break;
     case MULTIPLEX_CTRL_SET_MAX_CHUNKS:
-      if( pArg ) {
-        int nMaxChunks = *(int *)pArg;
-        if(( nMaxChunks<1 ) || ( nMaxChunks>SQLITE_MULTIPLEX_MAX_CHUNKS )){
-          rc = SQLITE_MISUSE;
-        }else{
-          pGroup->nMaxChunks = nMaxChunks;
-          rc = SQLITE_OK;
-        }
-      }
+      rc = SQLITE_OK;
       break;
     case SQLITE_FCNTL_SIZE_HINT:
     case SQLITE_FCNTL_CHUNK_SIZE:
@@ -940,7 +893,7 @@ static int multiplexFileControl(sqlite3_file *pConn, int op, void *pArg){
       rc = SQLITE_OK;
       break;
     default:
-      pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
+      pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL);
       if( pSubOpen ){
         rc = pSubOpen->pMethods->xFileControl(pSubOpen, op, pArg);
       }
@@ -954,7 +907,7 @@ 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, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
   if( pSubOpen ){
     return pSubOpen->pMethods->xSectorSize(pSubOpen);
   }
@@ -966,7 +919,7 @@ static int multiplexSectorSize(sqlite3_file *pConn){
 static int multiplexDeviceCharacteristics(sqlite3_file *pConn){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
   if( pSubOpen ){
     return pSubOpen->pMethods->xDeviceCharacteristics(pSubOpen);
   }
@@ -984,7 +937,7 @@ static int multiplexShmMap(
 ){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
   if( pSubOpen ){
     return pSubOpen->pMethods->xShmMap(pSubOpen, iRegion, szRegion, bExtend,pp);
   }
@@ -1001,7 +954,7 @@ static int multiplexShmLock(
 ){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
   if( pSubOpen ){
     return pSubOpen->pMethods->xShmLock(pSubOpen, ofst, n, flags);
   }
@@ -1013,7 +966,7 @@ static int multiplexShmLock(
 static void multiplexShmBarrier(sqlite3_file *pConn){
   multiplexConn *p = (multiplexConn*)pConn;
   int rc;
-  sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
   if( pSubOpen ){
     pSubOpen->pMethods->xShmBarrier(pSubOpen);
   }
@@ -1024,7 +977,7 @@ 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, 0, &rc, NULL);
+  sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL);
   if( pSubOpen ){
     return pSubOpen->pMethods->xShmUnmap(pSubOpen, deleteFlag);
   }
@@ -1054,11 +1007,6 @@ int sqlite3_multiplex_initialize(const char *zOrigVfsName, int makeDefault){
   if( !gMultiplex.pMutex ){
     return SQLITE_NOMEM;
   }
-  gMultiplex.zName = sqlite3_malloc(pOrigVfs->mxPathname);
-  if( !gMultiplex.zName ){
-    sqlite3_mutex_free(gMultiplex.pMutex);
-    return SQLITE_NOMEM;
-  }
   gMultiplex.pGroups = NULL;
   gMultiplex.isInitialized = 1;
   gMultiplex.pOrigVfs = pOrigVfs;
@@ -1119,7 +1067,6 @@ int sqlite3_multiplex_shutdown(void){
   if( gMultiplex.isInitialized==0 ) return SQLITE_MISUSE;
   if( gMultiplex.pGroups ) return SQLITE_MISUSE;
   gMultiplex.isInitialized = 0;
-  sqlite3_free(gMultiplex.zName);
   sqlite3_mutex_free(gMultiplex.pMutex);
   sqlite3_vfs_unregister(&gMultiplex.sThisVfs);
   memset(&gMultiplex, 0, sizeof(gMultiplex));
@@ -1221,8 +1168,8 @@ static int test_multiplex_dump(
           Tcl_NewIntObj(pGroup->flags));
 
     /* count number of chunks with open handles */
-    for(i=0; i<pGroup->nMaxChunks; i++){
-      if( pGroup->bOpen[i] ) nChunks++;
+    for(i=0; i<pGroup->nReal; i++){
+      if( pGroup->aReal[i].p!=0 ) nChunks++;
     }
     Tcl_ListObjAppendElement(interp, pGroupTerm,
           Tcl_NewIntObj(nChunks));
@@ -1230,7 +1177,7 @@ static int test_multiplex_dump(
     Tcl_ListObjAppendElement(interp, pGroupTerm,
           Tcl_NewIntObj(pGroup->nChunkSize));
     Tcl_ListObjAppendElement(interp, pGroupTerm,
-          Tcl_NewIntObj(pGroup->nMaxChunks));
+          Tcl_NewIntObj(pGroup->nReal));
 
     Tcl_ListObjAppendElement(interp, pResult, pGroupTerm);
   }
diff --git a/test/multiplex.test b/test/multiplex.test
index 9278e8427..93d4aafc1 100644
--- a/test/multiplex.test
+++ b/test/multiplex.test
@@ -49,6 +49,7 @@ proc multiplex_set {db name chunk_size max_chunks} {
 # and files with the chunk extension.
 proc multiplex_delete {name} {
   global g_max_chunks
+  forcedelete $name
   for {set i 0} {$i<$g_max_chunks} {incr i} {
     forcedelete [multiplex_name $name $i]
     forcedelete [multiplex_name $name-journal $i]
@@ -78,10 +79,10 @@ do_test multiplex-1.8 { sqlite3_multiplex_shutdown }               {SQLITE_OK}
 do_test multiplex-1.9.1  { sqlite3_multiplex_initialize "" 1 }     {SQLITE_OK}
 do_test multiplex-1.9.2  { sqlite3 db test.db }                    {}
 do_test multiplex-1.9.3  { multiplex_set db main 32768 16 }        {SQLITE_OK}
-do_test multiplex-1.9.4  { multiplex_set db main 32768 -1 }        {SQLITE_MISUSE}
+do_test multiplex-1.9.4  { multiplex_set db main 32768 -1 }        {SQLITE_OK}
 do_test multiplex-1.9.5  { multiplex_set db main -1 16 }           {SQLITE_MISUSE}
 do_test multiplex-1.9.6  { multiplex_set db main 31 16 }           {SQLITE_OK}
-do_test multiplex-1.9.7  { multiplex_set db main 32768 100 }       {SQLITE_MISUSE}
+do_test multiplex-1.9.7  { multiplex_set db main 32768 100 }       {SQLITE_OK}
 do_test multiplex-1.9.8  { multiplex_set db main 1073741824 1 }    {SQLITE_OK}
 do_test multiplex-1.9.9  { db close }                              {}
 do_test multiplex-1.9.10 { sqlite3_multiplex_shutdown }            {SQLITE_OK}
@@ -89,10 +90,10 @@ do_test multiplex-1.9.10 { sqlite3_multiplex_shutdown }            {SQLITE_OK}
 do_test multiplex-1.10.1  { sqlite3_multiplex_initialize "" 1 }                                  {SQLITE_OK}
 do_test multiplex-1.10.2  { sqlite3 db test.db }                                                 {}
 do_test multiplex-1.10.3  { lindex [ catchsql { SELECT multiplex_control(2, 32768); } ] 0 }      {0}
-do_test multiplex-1.10.4  { lindex [ catchsql { SELECT multiplex_control(3, -1); } ] 0 }         {1}
+do_test multiplex-1.10.4  { lindex [ catchsql { SELECT multiplex_control(3, -1); } ] 0 }         {0}
 do_test multiplex-1.10.5  { lindex [ catchsql { SELECT multiplex_control(2, -1); } ] 0 }         {1}
 do_test multiplex-1.10.6  { lindex [ catchsql { SELECT multiplex_control(2, 31); } ] 0 }         {0}
-do_test multiplex-1.10.7  { lindex [ catchsql { SELECT multiplex_control(3, 100); } ] 0 }        {1}
+do_test multiplex-1.10.7  { lindex [ catchsql { SELECT multiplex_control(3, 100); } ] 0 }        {0}
 do_test multiplex-1.10.8  { lindex [ catchsql { SELECT multiplex_control(2, 1073741824); } ] 0 } {0}
 do_test multiplex-1.10.9  { db close }                                                           {}
 do_test multiplex-1.10.10 { sqlite3_multiplex_shutdown }                                         {SQLITE_OK}
@@ -146,8 +147,9 @@ do_test multiplex-1.13.7  { sqlite3_multiplex_shutdown }
 sqlite3_multiplex_initialize "" 1
 multiplex_set db main 32768 16
 
+file delete -force test.x
 do_test multiplex-2.1.2 {
-  sqlite3 db test.db
+  sqlite3 db test.x
   execsql {
     PRAGMA page_size=1024;
     PRAGMA auto_vacuum=OFF;
@@ -159,7 +161,7 @@ do_test multiplex-2.1.2 {
     INSERT INTO t1 VALUES(2, randomblob(1100));
   }
 } {}
-do_test multiplex-2.1.3 { file size [multiplex_name test.db 0] } {4096}
+do_test multiplex-2.1.3 { file size [multiplex_name test.x 0] } {4096}
 do_test multiplex-2.1.4 {
   execsql { INSERT INTO t1 VALUES(3, randomblob(1100)) }
 } {}
@@ -167,10 +169,10 @@ do_test multiplex-2.1.4 {
 do_test multiplex-2.2.1 {
   execsql { INSERT INTO t1 VALUES(3, randomblob(1100)) }
 } {}
-do_test multiplex-2.2.3 { file size [multiplex_name test.db 0] } {6144}
+do_test multiplex-2.2.3 { file size [multiplex_name test.x 0] } {6144}
 
 do_test multiplex-2.3.1 {
-  sqlite3 db2 test2.db
+  sqlite3 db2 test2.x
   db2 close
 } {}
 
@@ -181,7 +183,7 @@ do_test multiplex-2.4.1 {
 do_test multiplex-2.4.2 {
   execsql { INSERT INTO t1 VALUES(3, randomblob(1100)) }
 } {}
-do_test multiplex-2.4.4 { file size [multiplex_name test.db 0] } {7168}
+do_test multiplex-2.4.4 { file size [multiplex_name test.x 0] } {7168}
 do_test multiplex-2.4.99 {
   db close
   sqlite3_multiplex_shutdown
@@ -189,9 +191,9 @@ do_test multiplex-2.4.99 {
 
 
 do_test multiplex-2.5.1 {
-  multiplex_delete test.db
+  multiplex_delete test.x
   sqlite3_multiplex_initialize "" 1
-  sqlite3 db test.db
+  sqlite3 db test.x
   multiplex_set db main 4096 16
 } {SQLITE_OK}
 
@@ -236,8 +238,8 @@ do_test multiplex-2.5.8 {
   db eval {SELECT a,length(b) FROM t1 WHERE a=4}
 } {4 4000}
 
-do_test multiplex-2.5.9 { file size [multiplex_name test.db 0] } [list $g_chunk_size]
-do_test multiplex-2.5.10 { file size [multiplex_name test.db 1] } [list $g_chunk_size]
+do_test multiplex-2.5.9 { file size [multiplex_name test.x 0] } [list $g_chunk_size]
+do_test multiplex-2.5.10 { file size [multiplex_name test.x 1] } [list $g_chunk_size]
 
 do_test multiplex-2.5.99 {
   db close
@@ -523,50 +525,6 @@ do_faultsim_test multiplex-5.5 -prep {
   multiplex_set db main 32768 16
 }
 
-# test that mismatch filesize is detected
-#
-# Do not run this test if $::G(perm:presql) is set. If it is set, then the
-# expected IO error will occur within the Tcl [sqlite3] wrapper, not within
-# the first SQL statement executed below. This breaks the test case.
-#
-if {0==[info exists ::G(perm:presql)] || $::G(perm:presql) == ""} {
-  set all_journal_modes {delete persist truncate memory off}
-  foreach jmode $all_journal_modes {
-    do_test multiplex-5.6.1.$jmode {
-      sqlite3_multiplex_shutdown
-      multiplex_delete test.db
-      sqlite3 db test.db
-      db eval {
-        PRAGMA page_size = 1024;
-        PRAGMA auto_vacuum = off;
-      }
-      db eval "PRAGMA journal_mode = $jmode;"
-    } $jmode
-    do_test multiplex-5.6.2.$jmode {
-      execsql {
-        CREATE TABLE t1(a, b);
-        INSERT INTO t1 VALUES(1, randomblob(15000));
-        INSERT INTO t1 VALUES(2, randomblob(15000));
-        INSERT INTO t1 VALUES(3, randomblob(15000));
-        INSERT INTO t1 VALUES(4, randomblob(15000));
-        INSERT INTO t1 VALUES(5, randomblob(15000));
-      }
-      db close
-      sqlite3_multiplex_initialize "" 1
-      sqlite3 db test.db
-      multiplex_set db main 4096 16
-    } {SQLITE_OK}
-    do_test multiplex-5.6.3.$jmode {
-      catchsql {
-        INSERT INTO t1 VALUES(6, randomblob(15000));
-      }
-    } {1 {disk I/O error}}
-    do_test multiplex-5.6.4.$jmode {
-      db close
-    } {}
-  }
-}
-
 #-------------------------------------------------------------------------
 # Test that you can vacuum a multiplex'ed DB.  
 
@@ -575,8 +533,9 @@ ifcapable vacuum {
 sqlite3_multiplex_shutdown
 do_test multiplex-6.0.0 {
   multiplex_delete test.db
+  multiplex_delete test.x
   sqlite3_multiplex_initialize "" 1
-  sqlite3 db test.db
+  sqlite3 db test.x
   multiplex_set db main 4096 16
 } {SQLITE_OK}
 
@@ -592,8 +551,8 @@ do_test multiplex-6.1.0 {
     INSERT INTO t1 VALUES(2, randomblob($g_chunk_size));
   }
 } {}
-do_test multiplex-6.2.1 { file size [multiplex_name test.db 0] } [list $g_chunk_size]
-do_test multiplex-6.2.2 { file size [multiplex_name test.db 1] } [list $g_chunk_size]
+do_test multiplex-6.2.1 { file size [multiplex_name test.x 0] } [list $g_chunk_size]
+do_test multiplex-6.2.2 { file size [multiplex_name test.x 1] } [list $g_chunk_size]
 
 do_test multiplex-6.3.0 {
   execsql { VACUUM }
@@ -601,7 +560,7 @@ do_test multiplex-6.3.0 {
 
 do_test multiplex-6.99 {
   db close
-  multiplex_delete test.db
+  multiplex_delete test.x
   sqlite3_multiplex_shutdown
 } {SQLITE_OK}