Extend the code in memjournal.c so that it subsumes the role of journal.c. And (untested) can flush journal or statement journal files to disk after they grow to a specified size.

FossilOrigin-Name: e0b0b4316531fc8afa74b4882d9c74a91030ec69

manifest

@@ -1,5 +1,5 @@
-C Tighter\sdescription\sof\sI/O\sstats\sin\sthe\sshell.\s\sShow\sI/O\sstats\son\sspeedtest1.c.
+C Extend\sthe\scode\sin\smemjournal.c\sso\sthat\sit\ssubsumes\sthe\srole\sof\sjournal.c.\sAnd\s(untested)\scan\sflush\sjournal\sor\sstatement\sjournal\sfiles\sto\sdisk\safter\sthey\sgrow\sto\sa\sspecified\ssize.
-D 2016-02-27T19:19:22.849
+D 2016-02-27T20:14:55.339
 F Makefile.in 4e90dc1521879022aa9479268a4cd141d1771142
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 4f319afb7c049d40aff7af6e8c4e7cc2ba18e079
@@ -311,7 +311,7 @@ F src/hash.c 4263fbc955f26c2e8cdc0cf214bc42435aa4e4f5
 F src/hash.h c8f3c31722cf3277d03713909761e152a5b81094
 F src/hwtime.h d32741c8f4df852c7d959236615444e2b1063b08
 F src/insert.c 9ca97272e9f74ed0efddf3b4350ee12740cebbef
-F src/journal.c fe3a3e2559ce3ce9d371afd30fbabbc074174575
+F src/journal.c 673cbdde5676eb0c55848f561575d45b609c820d
 F src/legacy.c 75d3023be8f0d2b99d60f905090341a03358c58e
 F src/loadext.c 9e2a41adcaff16ebc1ebff1f336cbf33de55396f
 F src/main.c be9309f442ec291177642d2e48e82290e0951f4b
@@ -321,7 +321,7 @@ F src/mem1.c 6919bcf12f221868ea066eec27e579fed95ce98b
 F src/mem2.c f1940d9e91948dd6a908fbb9ce3835c36b5d83c3
 F src/mem3.c 8768ac94694f31ffaf8b4d0ea5dc08af7010a35a
 F src/mem5.c 9bf955937b07f8c32541c8a9991f33ce3173d944
-F src/memjournal.c 349a04fb803db40532cde0993e39758f1acaecce
+F src/memjournal.c 8d045e50120e9988e63bb0af69187e1e5e35122f
 F src/msvc.h d9ba56c6851227ab44b3f228a35f3f5772296495
 F src/mutex.c 8e45800ee78e0cd1f1f3fe8e398853307f4a085c
 F src/mutex.h 779d588e3b7756ec3ecf7d78cde1d84aba414f85
@@ -329,14 +329,14 @@ F src/mutex_noop.c 9d4309c075ba9cc7249e19412d3d62f7f94839c4
 F src/mutex_unix.c 27bb6cc49485ee46711a6580ab7b3f1402211d23
 F src/mutex_w32.c 5e6fe1c298fb5a8a15aaed4161d5759311431c17
 F src/notify.c 9711a7575036f0d3040ba61bc6e217f13a9888e7
-F src/os.c ca9a104b677328ee037cfdf1a54a16fd1805e8c9
+F src/os.c f89e3ca1c2e3d5015b847aec60371c474acbac82
 F src/os.h 3e57a24e2794a94d3cf2342c6d9a884888cd96bf
 F src/os_common.h b2f4707a603e36811d9b1a13278bffd757857b85
 F src/os_setup.h c9d4553b5aaa6f73391448b265b89bed0b890faa
 F src/os_unix.c 3a6f20736dfb8a0949cdd66553fdf59f6604be35
 F src/os_win.c f0d7aa603eb6262143d7169a222aea07c4fca91d
 F src/os_win.h eb7a47aa17b26b77eb97e4823f20a00b8bda12ca
-F src/pager.c d034c69b958c01289eb8070cbf902e1a68cd7e0b
+F src/pager.c e2bf43b506447d649e9d9266e988007ae7248699
 F src/pager.h e1d38a2f14849e219df0f91f8323504d134c8a56
 F src/parse.y c3ce2c4a7cbf0b699239be6b2a945c5cb51875e2
 F src/pcache.c 647bb53a86b7bbcf55ad88089b3ea5a9170b90df
@@ -354,7 +354,7 @@ F src/shell.c 5e0ab1e708dc294330ccd8230536e1801f60822e
 F src/sqlite.h.in 57d2a02b14c9ec4f7cb294153eaf62294dc5aa68
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h dfbe62ffd95b99afe2140d8c35b180d11924072d
-F src/sqliteInt.h 63c0e1b5b5d608a1ba2303fe3a554b859a120406
+F src/sqliteInt.h 3c4ed7e5dcb8b7d4cd4ab258ee7d0e0d0368f014
 F src/sqliteLimit.h 216557999cb45f2e3578ed53ebefe228d779cb46
 F src/status.c 70912d7be68e9e2dbc4010c93d344af61d4c59ba
 F src/table.c 5226df15ab9179b9ed558d89575ea0ce37b03fc9
@@ -1451,7 +1451,10 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 3c36948f16b58fe8042c37d0df634308b4e48217
+P f681d800340e0e710f73d0f7c09101f899249183
-R 2b473c8c6b36608ca875feba0d8cbb83
+R f456c30e495865d50fc2c9c2ddb305ed
-U drh
+T *branch * memjournal-exp
-Z 565e8454d2408a569a86791d9e6b12a6
+T *sym-memjournal-exp *
+T -sym-trunk *
+U dan
+Z dad681f00ca4c98b68e43d3727f3c92e

manifest.uuid

@@ -1 +1 @@
-f681d800340e0e710f73d0f7c09101f899249183
+e0b0b4316531fc8afa74b4882d9c74a91030ec69

src/journal.c

@@ -24,6 +24,7 @@
 **      buffer, or
 **   2) The sqlite3JournalCreate() function is called.
 */
+#if 0 
 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
 #include "sqliteInt.h"
 
@@ -254,3 +255,4 @@ int sqlite3JournalSize(sqlite3_vfs *pVfs){
   return (pVfs->szOsFile+sizeof(JournalFile));
 }
 #endif
+#endif

src/memjournal.c

@@ -21,24 +21,28 @@ typedef struct MemJournal MemJournal;
 typedef struct FilePoint FilePoint;
 typedef struct FileChunk FileChunk;
 
-/* Space to hold the rollback journal is allocated in increments of
-** this many bytes.
-**
-** The size chosen is a little less than a power of two.  That way,
-** the FileChunk object will have a size that almost exactly fills
-** a power-of-two allocation.  This minimizes wasted space in power-of-two
-** memory allocators.
-*/
-#define JOURNAL_CHUNKSIZE ((int)(1024-sizeof(FileChunk*)))
-
 /*
 ** The rollback journal is composed of a linked list of these structures.
+**
+** The zChunk array is always at least 8 bytes in size - usually much more.
+** Its actual size is stored in the MemJournal.nChunkSize variable.
 */
 struct FileChunk {
   FileChunk *pNext;               /* Next chunk in the journal */
-  u8 zChunk[JOURNAL_CHUNKSIZE];   /* Content of this chunk */
+  u8 zChunk[8];                   /* Content of this chunk */
 };
 
+/*
+** By default, allocate this many bytes of memory for each FileChunk object.
+*/
+#define MEMJOURNAL_DFLT_FILECHUNKSIZE 1024
+
+/*
+** For chunk size nChunkSize, return the number of bytes that should
+** be allocated for each FileChunk structure.
+*/
+#define fileChunkSize(nChunkSize) (sizeof(FileChunk) + ((nChunkSize)-8))
+
 /*
 ** An instance of this object serves as a cursor into the rollback journal.
 ** The cursor can be either for reading or writing.
@@ -49,14 +53,23 @@ struct FilePoint {
 };
 
 /*
-** This subclass is a subclass of sqlite3_file.  Each open memory-journal
+** This structure is a subclass of sqlite3_file. Each open memory-journal
 ** is an instance of this class.
 */
 struct MemJournal {
-  sqlite3_io_methods *pMethod;    /* Parent class. MUST BE FIRST */
+  const sqlite3_io_methods *pMethod; /* Parent class. MUST BE FIRST */
+  int nChunkSize;                 /* In-memory chunk-size */
+
+  int nBuf;                       /* Bytes of data before flushing */
+  int nSize;                      /* Bytes of data currently in memory */
   FileChunk *pFirst;              /* Head of in-memory chunk-list */
   FilePoint endpoint;             /* Pointer to the end of the file */
   FilePoint readpoint;            /* Pointer to the end of the last xRead() */
+
+  int flags;                      /* xOpen flags */
+  sqlite3_vfs *pVfs;              /* The "real" underlying VFS */
+  const char *zJournal;           /* Name of the journal file */
+  sqlite3_file *pReal;            /* The "real" underlying file descriptor */
 };
 
 /*
@@ -70,30 +83,32 @@ static int memjrnlRead(
   sqlite_int64 iOfst     /* Begin reading at this offset */
 ){
   MemJournal *p = (MemJournal *)pJfd;
+  if( p->pReal ){
+    return sqlite3OsRead(p->pReal, zBuf, iAmt, iOfst);
+  }else if( (iAmt+iOfst)>p->endpoint.iOffset ){
+    return SQLITE_IOERR_SHORT_READ;
+  }else{
     u8 *zOut = zBuf;
     int nRead = iAmt;
     int iChunkOffset;
     FileChunk *pChunk;
 
-  /* SQLite never tries to read past the end of a rollback journal file */
-  assert( iOfst+iAmt<=p->endpoint.iOffset );
-
     if( p->readpoint.iOffset!=iOfst || iOfst==0 ){
       sqlite3_int64 iOff = 0;
       for(pChunk=p->pFirst; 
-        ALWAYS(pChunk) && (iOff+JOURNAL_CHUNKSIZE)<=iOfst;
+          ALWAYS(pChunk) && (iOff+p->nChunkSize)<=iOfst;
           pChunk=pChunk->pNext
       ){
-      iOff += JOURNAL_CHUNKSIZE;
+        iOff += p->nChunkSize;
       }
     }else{
       pChunk = p->readpoint.pChunk;
     }
 
-  iChunkOffset = (int)(iOfst%JOURNAL_CHUNKSIZE);
+    iChunkOffset = (int)(iOfst%p->nChunkSize);
     do {
-    int iSpace = JOURNAL_CHUNKSIZE - iChunkOffset;
+      int iSpace = p->nChunkSize - iChunkOffset;
-    int nCopy = MIN(nRead, (JOURNAL_CHUNKSIZE - iChunkOffset));
+      int nCopy = MIN(nRead, (p->nChunkSize - iChunkOffset));
       memcpy(zOut, &pChunk->zChunk[iChunkOffset], nCopy);
       zOut += nCopy;
       nRead -= iSpace;
@@ -101,10 +116,63 @@ static int memjrnlRead(
     } while( nRead>=0 && (pChunk=pChunk->pNext)!=0 && nRead>0 );
     p->readpoint.iOffset = iOfst+iAmt;
     p->readpoint.pChunk = pChunk;
+  }
 
   return SQLITE_OK;
 }
 
+/*
+** Free the list of FileChunk structures headed at MemJournal.pFirst.
+*/
+static void memjrnlFreeChunks(MemJournal *p){
+  FileChunk *pIter;
+  FileChunk *pNext;
+  for(pIter=p->pFirst; pIter; pIter=pNext){
+    pNext = pIter->pNext;
+    sqlite3_free(pIter);
+  } 
+  p->pFirst = 0;
+}
+
+/*
+** Flush the contents of memory to a real file on disk.
+*/
+static int createFile(MemJournal *p){
+  int rc = SQLITE_OK;
+  if( !p->pReal ){
+    sqlite3_file *pReal = (sqlite3_file *)&p[1];
+    rc = sqlite3OsOpen(p->pVfs, p->zJournal, pReal, p->flags, 0);
+    if( rc==SQLITE_OK ){
+      int nChunk = p->nChunkSize;
+      i64 iOff = 0;
+      FileChunk *pIter;
+      p->pReal = pReal;
+      for(pIter=p->pFirst; pIter && rc==SQLITE_OK; pIter=pIter->pNext){
+        int nWrite = nChunk;
+        if( pIter==p->endpoint.pChunk ){
+          nWrite = p->endpoint.iOffset % p->nChunkSize;
+          if( nWrite==0 ) nWrite = p->nChunkSize;
+        }
+        rc = sqlite3OsWrite(pReal, pIter->zChunk, nWrite, iOff);
+        iOff += nWrite;
+      }
+      if( rc!=SQLITE_OK ){
+        /* If an error occurred while writing to the file, close it before
+        ** returning. This way, SQLite uses the in-memory journal data to 
+        ** roll back changes made to the internal page-cache before this
+        ** function was called.  */
+        sqlite3OsClose(pReal);
+        p->pReal = 0;
+      }else{
+        /* No error has occurred. Free the in-memory buffers. */
+        memjrnlFreeChunks(p);
+      }
+    }
+  }
+  return rc;
+}
+
+
 /*
 ** Write data to the file.
 */
@@ -118,20 +186,40 @@ static int memjrnlWrite(
   int nWrite = iAmt;
   u8 *zWrite = (u8 *)zBuf;
 
-  /* An in-memory journal file should only ever be appended to. Random
+  /* If the file has already been created on disk. */
-  ** access writes are not required by sqlite.
+  if( p->pReal ){
-  */
+    return sqlite3OsWrite(p->pReal, zBuf, iAmt, iOfst);
-  assert( iOfst==p->endpoint.iOffset );
+  }
-  UNUSED_PARAMETER(iOfst);
 
+  /* If the file should be created now. */
+  else if( p->nBuf>0 && (iAmt+iOfst)>p->nBuf ){
+    int rc = createFile(p);
+    if( rc==SQLITE_OK ){
+      rc = memjrnlWrite(pJfd, zBuf, iAmt, iOfst);
+    }
+    return rc;
+  }
+
+  /* If the contents of this write should be stored in memory */
+  else{
+    /* An in-memory journal file should only ever be appended to. Random
+    ** access writes are not required. The only exception to this is when
+    ** the in-memory journal is being used by a connection using the
+    ** atomic-write optimization. In this case the first 28 bytes of the
+    ** journal file may be written as part of committing the transaction. */ 
+    assert( iOfst==p->endpoint.iOffset || iOfst==0 );
+    if( iOfst==0 && p->pFirst ){
+      assert( p->nChunkSize>iAmt );
+      memcpy(p->pFirst->zChunk, zBuf, iAmt);
+    }else{
       while( nWrite>0 ){
         FileChunk *pChunk = p->endpoint.pChunk;
-    int iChunkOffset = (int)(p->endpoint.iOffset%JOURNAL_CHUNKSIZE);
+        int iChunkOffset = (int)(p->endpoint.iOffset%p->nChunkSize);
-    int iSpace = MIN(nWrite, JOURNAL_CHUNKSIZE - iChunkOffset);
+        int iSpace = MIN(nWrite, p->nChunkSize - iChunkOffset);
 
         if( iChunkOffset==0 ){
           /* New chunk is required to extend the file. */
-      FileChunk *pNew = sqlite3_malloc(sizeof(FileChunk));
+          FileChunk *pNew = sqlite3_malloc(fileChunkSize(p->nChunkSize));
           if( !pNew ){
             return SQLITE_IOERR_NOMEM_BKPT;
           }
@@ -151,6 +239,9 @@ static int memjrnlWrite(
         nWrite -= iSpace;
         p->endpoint.iOffset += iSpace;
       }
+      p->nSize = iAmt + iOfst;
+    }
+  }
 
   return SQLITE_OK;
 }
@@ -160,16 +251,16 @@ static int memjrnlWrite(
 */
 static int memjrnlTruncate(sqlite3_file *pJfd, sqlite_int64 size){
   MemJournal *p = (MemJournal *)pJfd;
-  FileChunk *pChunk;
+  if( p->pReal ){
-  assert(size==0);
+    return sqlite3OsTruncate(p->pReal, size);
-  UNUSED_PARAMETER(size);
+  }else if( size==0 ){
-  pChunk = p->pFirst;
+    memjrnlFreeChunks(p);
-  while( pChunk ){
+    p->nSize = 0;
-    FileChunk *pTmp = pChunk;
+    p->endpoint.pChunk = 0;
-    pChunk = pChunk->pNext;
+    p->endpoint.iOffset = 0;
-    sqlite3_free(pTmp);
+    p->readpoint.pChunk = 0;
+    p->readpoint.iOffset = 0;
   }
-  sqlite3MemJournalOpen(pJfd);
   return SQLITE_OK;
 }
 
@@ -177,21 +268,23 @@ static int memjrnlTruncate(sqlite3_file *pJfd, sqlite_int64 size){
 ** Close the file.
 */
 static int memjrnlClose(sqlite3_file *pJfd){
-  memjrnlTruncate(pJfd, 0);
+  MemJournal *p = (MemJournal *)pJfd;
+  memjrnlFreeChunks(p);
+  if( p->pReal ) sqlite3OsClose(p->pReal);
   return SQLITE_OK;
 }
 
-
 /*
 ** Sync the file.
 **
-** Syncing an in-memory journal is a no-op.  And, in fact, this routine
+** If the real file has been created, call its xSync method. Otherwise, 
-** is never called in a working implementation.  This implementation
+** syncing an in-memory journal is a no-op. 
-** exists purely as a contingency, in case some malfunction in some other
-** part of SQLite causes Sync to be called by mistake.
 */
-static int memjrnlSync(sqlite3_file *NotUsed, int NotUsed2){
+static int memjrnlSync(sqlite3_file *pJfd, int flags){
-  UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  MemJournal *p = (MemJournal *)pJfd;
+  if( p->pReal ){
+    return sqlite3OsSync(p->pReal, flags);
+  }
   return SQLITE_OK;
 }
 
@@ -200,6 +293,9 @@ static int memjrnlSync(sqlite3_file *NotUsed, int NotUsed2){
 */
 static int memjrnlFileSize(sqlite3_file *pJfd, sqlite_int64 *pSize){
   MemJournal *p = (MemJournal *)pJfd;
+  if( p->pReal ){
+    return sqlite3OsFileSize(p->pReal, pSize);
+  }
   *pSize = (sqlite_int64) p->endpoint.iOffset;
   return SQLITE_OK;
 }
@@ -231,25 +327,91 @@ static const struct sqlite3_io_methods MemJournalMethods = {
 
 /* 
 ** Open a journal file. 
+**
+** The behaviour of the journal file depends on the value of parameter 
+** nBuf. If nBuf is 0, then the journal file is always create and 
+** accessed using the underlying VFS. If nBuf is less than zero, then
+** all content is always stored in main-memory. Finally, if nBuf is a
+** positive value, then the journal file is initially created in-memory
+** but may be flushed to disk later on. In this case the journal file is
+** flushed to disk either when it grows larger than nBuf bytes in size,
+** or when sqlite3JournalCreate() is called.
+*/
+int sqlite3JournalOpen(
+  sqlite3_vfs *pVfs,         /* The VFS to use for actual file I/O */
+  const char *zName,         /* Name of the journal file */
+  sqlite3_file *pJfd,        /* Preallocated, blank file handle */
+  int flags,                 /* Opening flags */
+  int nBuf                   /* Bytes buffered before opening the file */
+){
+  MemJournal *p = (MemJournal*)pJfd;
+
+  /* Zero the file-handle object. If nBuf was passed zero, initialize
+  ** it using the sqlite3OsOpen() function of the underlying VFS. In this
+  ** case none of the code in this module is executed as a result of calls
+  ** made on the journal file-handle.  */
+  memset(p, 0, sizeof(MemJournal));
+  if( nBuf==0 ){
+    return sqlite3OsOpen(pVfs, zName, pJfd, flags, 0);
+  }
+
+  if( nBuf>0 ){
+    p->nChunkSize = nBuf;
+  }else{
+    p->nChunkSize = 8 + MEMJOURNAL_DFLT_FILECHUNKSIZE - sizeof(FileChunk);
+    assert( MEMJOURNAL_DFLT_FILECHUNKSIZE==fileChunkSize(p->nChunkSize) );
+  }
+
+  p->pMethod = (const sqlite3_io_methods*)&MemJournalMethods;
+  p->nBuf = nBuf;
+  p->flags = flags;
+  p->zJournal = zName;
+  p->pVfs = pVfs;
+  return SQLITE_OK;
+}
+
+/*
+** Open an in-memory journal file.
 */
 void sqlite3MemJournalOpen(sqlite3_file *pJfd){
-  MemJournal *p = (MemJournal *)pJfd;
+  sqlite3JournalOpen(0, 0, pJfd, 0, -1);
-  assert( EIGHT_BYTE_ALIGNMENT(p) );
-  memset(p, 0, sqlite3MemJournalSize());
-  p->pMethod = (sqlite3_io_methods*)&MemJournalMethods;
 }
 
 /*
-** Return true if the file-handle passed as an argument is 
+** Return true if the file-handle passed as an argument is an in-memory 
-** an in-memory journal 
+** journal.
 */
 int sqlite3IsMemJournal(sqlite3_file *pJfd){
-  return pJfd->pMethods==&MemJournalMethods;
+  return pJfd->pMethods==&MemJournalMethods && ((MemJournal*)pJfd)->pReal==0;
 }
 
 /*
-** Return the number of bytes required to store a MemJournal file descriptor.
+** If the argument p points to a MemJournal structure that is not an 
+** in-memory-only journal file, and the underlying file has not yet been 
+** created, create it now.
 */
-int sqlite3MemJournalSize(void){
+int sqlite3JournalCreate(sqlite3_file *p){
-  return sizeof(MemJournal);
+  int rc = SQLITE_OK;
+  if( p->pMethods==&MemJournalMethods && ((MemJournal*)p)->nBuf>=0 ){
+    rc = createFile((MemJournal*)p);
   }
+  return rc;
+}
+
+/*
+** The file-handle passed as teh only argument is open on a journal file.
+** Return true if this "journal file" is actually stored in heap memory,
+** or false otherwise.
+*/
+int sqlite3JournalIsInMemory(sqlite3_file *p){
+  return p->pMethods==&MemJournalMethods && ((MemJournal*)p)->pReal==0;
+}
+
+/* 
+** Return the number of bytes required to store a JournalFile that uses vfs
+** pVfs to create the underlying on-disk files.
+*/
+int sqlite3JournalSize(sqlite3_vfs *pVfs){
+  return pVfs->szOsFile + sizeof(MemJournal);
+}
+

src/os.c

@@ -66,7 +66,7 @@ int sqlite3_open_file_count = 0;
 #if defined(SQLITE_TEST)
 int sqlite3_memdebug_vfs_oom_test = 1;
   #define DO_OS_MALLOC_TEST(x)                                       \
-  if (sqlite3_memdebug_vfs_oom_test && (!x || !sqlite3IsMemJournal(x))) {  \
+  if (sqlite3_memdebug_vfs_oom_test && (!x || !sqlite3JournalIsInMemory(x))) { \
     void *pTstAlloc = sqlite3Malloc(10);                             \
     if (!pTstAlloc) return SQLITE_IOERR_NOMEM_BKPT;                  \
     sqlite3_free(pTstAlloc);                                         \

src/pager.c

@@ -1724,7 +1724,7 @@ static void releaseAllSavepoints(Pager *pPager){
   for(ii=0; ii<pPager->nSavepoint; ii++){
     sqlite3BitvecDestroy(pPager->aSavepoint[ii].pInSavepoint);
   }
-  if( !pPager->exclusiveMode || sqlite3IsMemJournal(pPager->sjfd) ){
+  if( !pPager->exclusiveMode || sqlite3JournalIsInMemory(pPager->sjfd) ){
     sqlite3OsClose(pPager->sjfd);
   }
   sqlite3_free(pPager->aSavepoint);
@@ -1962,8 +1962,8 @@ static int pager_end_transaction(Pager *pPager, int hasMaster, int bCommit){
     assert( !pagerUseWal(pPager) );
 
     /* Finalize the journal file. */
-    if( sqlite3IsMemJournal(pPager->jfd) ){
+    if( sqlite3JournalIsInMemory(pPager->jfd) ){
-      assert( pPager->journalMode==PAGER_JOURNALMODE_MEMORY );
+      /* assert( pPager->journalMode==PAGER_JOURNALMODE_MEMORY ); */
       sqlite3OsClose(pPager->jfd);
     }else if( pPager->journalMode==PAGER_JOURNALMODE_TRUNCATE ){
       if( pPager->journalOff==0 ){
@@ -1991,7 +1991,7 @@ static int pager_end_transaction(Pager *pPager, int hasMaster, int bCommit){
       ** file should be closed and deleted. If this connection writes to
       ** the database file, it will do so using an in-memory journal. 
       */
-      int bDelete = (!pPager->tempFile && sqlite3JournalExists(pPager->jfd));
+      int bDelete = (!pPager->tempFile&&!sqlite3JournalIsInMemory(pPager->jfd));
       assert( pPager->journalMode==PAGER_JOURNALMODE_DELETE 
            || pPager->journalMode==PAGER_JOURNALMODE_MEMORY 
            || pPager->journalMode==PAGER_JOURNALMODE_WAL 
@@ -4578,18 +4578,8 @@ int sqlite3PagerOpen(
   int nUri = 0;            /* Number of bytes of URI args at *zUri */
 
   /* Figure out how much space is required for each journal file-handle
-  ** (there are two of them, the main journal and the sub-journal). This
+  ** (there are two of them, the main journal and the sub-journal).  */
-  ** is the maximum space required for an in-memory journal file handle 
-  ** and a regular journal file-handle. Note that a "regular journal-handle"
-  ** may be a wrapper capable of caching the first portion of the journal
-  ** file in memory to implement the atomic-write optimization (see 
-  ** source file journal.c).
-  */
-  if( sqlite3JournalSize(pVfs)>sqlite3MemJournalSize() ){
   journalFileSize = ROUND8(sqlite3JournalSize(pVfs));
-  }else{
-    journalFileSize = ROUND8(sqlite3MemJournalSize());
-  }
 
   /* Set the output variable to NULL in case an error occurs. */
   *ppPager = 0;
@@ -6667,7 +6657,7 @@ int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint){
     if( op==SAVEPOINT_RELEASE ){
       if( nNew==0 && isOpen(pPager->sjfd) ){
         /* Only truncate if it is an in-memory sub-journal. */
-        if( sqlite3IsMemJournal(pPager->sjfd) ){
+        if( sqlite3JournalIsInMemory(pPager->sjfd) ){
           rc = sqlite3OsTruncate(pPager->sjfd, 0);
           assert( rc==SQLITE_OK );
         }

src/sqliteInt.h

@@ -4004,15 +4004,12 @@ int sqlite3FindInIndex(Parse *, Expr *, u32, int*);
   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
   int sqlite3JournalSize(sqlite3_vfs *);
   int sqlite3JournalCreate(sqlite3_file *);
-  int sqlite3JournalExists(sqlite3_file *p);
 #else
   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
-  #define sqlite3JournalExists(p) 1
 #endif
 
+int sqlite3JournalIsInMemory(sqlite3_file *p);
 void sqlite3MemJournalOpen(sqlite3_file *);
-int sqlite3MemJournalSize(void);
-int sqlite3IsMemJournal(sqlite3_file *);
 
 void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p);
 #if SQLITE_MAX_EXPR_DEPTH>0