Corner-case changes to the bytecode virtual table for testability and

correctness.

FossilOrigin-Name: baa720e4a88f268ed95337daab5f434fd3263b00f09101cddc6424765bf3b722

Makefile.in

@@ -190,7 +190,8 @@ LIBOBJS0 = alter.lo analyze.lo attach.lo auth.lo \
          table.lo threads.lo tokenize.lo treeview.lo trigger.lo \
          update.lo userauth.lo upsert.lo util.lo vacuum.lo \
          vdbe.lo vdbeapi.lo vdbeaux.lo vdbeblob.lo vdbemem.lo vdbesort.lo \
-         vdbetrace.lo wal.lo walker.lo where.lo wherecode.lo whereexpr.lo \
+         vdbetrace.lo vdbevtab.lo \
+         wal.lo walker.lo where.lo wherecode.lo whereexpr.lo \
          window.lo utf.lo vtab.lo
 
 # Object files for the amalgamation.
@@ -296,6 +297,7 @@ SRC = \
   $(TOP)/src/vdbemem.c \
   $(TOP)/src/vdbesort.c \
   $(TOP)/src/vdbetrace.c \
+  $(TOP)/src/vdbevtab.c \
   $(TOP)/src/vdbeInt.h \
   $(TOP)/src/vtab.c \
   $(TOP)/src/vxworks.h \
@@ -502,6 +504,7 @@ TESTSRC2 = \
   $(TOP)/src/vdbe.c \
   $(TOP)/src/vdbemem.c \
   $(TOP)/src/vdbetrace.c \
+  $(TOP)/src/vdbevtab.c \
   $(TOP)/src/where.c \
   $(TOP)/src/wherecode.c \
   $(TOP)/src/whereexpr.c \
@@ -607,6 +610,7 @@ SHELL_OPT += -DSQLITE_ENABLE_UNKNOWN_SQL_FUNCTION
 SHELL_OPT += -DSQLITE_ENABLE_STMTVTAB
 SHELL_OPT += -DSQLITE_ENABLE_DBPAGE_VTAB
 SHELL_OPT += -DSQLITE_ENABLE_DBSTAT_VTAB
+SHELL_OPT += -DSQLITE_ENABLE_BYTECODE_VTAB
 SHELL_OPT += -DSQLITE_ENABLE_OFFSET_SQL_FUNC
 SHELL_OPT += -DSQLITE_ENABLE_DESERIALIZE
 FUZZERSHELL_OPT = -DSQLITE_ENABLE_JSON1
@@ -619,6 +623,7 @@ FUZZCHECK_OPT += -DSQLITE_ENABLE_FTS4
 FUZZCHECK_OPT += -DSQLITE_ENABLE_RTREE
 FUZZCHECK_OPT += -DSQLITE_ENABLE_GEOPOLY
 FUZZCHECK_OPT += -DSQLITE_ENABLE_DBSTAT_VTAB
+FUZZCHECK_OPT += -DSQLITE_ENABLE_BYTECODE_VTAB
 FUZZCHECK_SRC = $(TOP)/test/fuzzcheck.c $(TOP)/test/ossfuzz.c
 DBFUZZ_OPT =
 
@@ -688,6 +693,7 @@ DBFUZZ2_OPTS = \
   -DSQLITE_ENABLE_DESERIALIZE \
   -DSQLITE_DEBUG \
   -DSQLITE_ENABLE_DBSTAT_VTAB \
+  -DSQLITE_ENABLE_BYTECODE_VTAB \
   -DSQLITE_ENABLE_RTREE \
   -DSQLITE_ENABLE_FTS4 \
   -DSQLITE_ENABLE_FTS5
@@ -1004,6 +1010,9 @@ vdbesort.lo:	$(TOP)/src/vdbesort.c $(HDR)
 vdbetrace.lo:	$(TOP)/src/vdbetrace.c $(HDR)
 	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/vdbetrace.c
 
+vdbevtab.lo:	$(TOP)/src/vdbevtab.c $(HDR)
+	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/vdbevtab.c
+
 vtab.lo:	$(TOP)/src/vtab.c $(HDR)
 	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/vtab.c
 
@@ -1211,6 +1220,7 @@ TESTFIXTURE_FLAGS += -DSQLITE_SERIES_CONSTRAINT_VERIFY=1
 TESTFIXTURE_FLAGS += -DSQLITE_DEFAULT_PAGE_SIZE=1024
 TESTFIXTURE_FLAGS += -DSQLITE_ENABLE_STMTVTAB
 TESTFIXTURE_FLAGS += -DSQLITE_ENABLE_DBPAGE_VTAB
+TESTFIXTURE_FLAGS += -DSQLITE_ENABLE_BYTECODE_VTAB
 TESTFIXTURE_FLAGS += -DSQLITE_ENABLE_DESERIALIZE
 
 TESTFIXTURE_SRC0 = $(TESTSRC2) libsqlite3.la

Makefile.msc

@@ -357,6 +357,7 @@ OPT_FEATURE_FLAGS = $(OPT_FEATURE_FLAGS) -DSQLITE_ENABLE_JSON1=1
 OPT_FEATURE_FLAGS = $(OPT_FEATURE_FLAGS) -DSQLITE_ENABLE_STMTVTAB=1
 OPT_FEATURE_FLAGS = $(OPT_FEATURE_FLAGS) -DSQLITE_ENABLE_DBPAGE_VTAB=1
 OPT_FEATURE_FLAGS = $(OPT_FEATURE_FLAGS) -DSQLITE_ENABLE_DBSTAT_VTAB=1
+OPT_FEATURE_FLAGS = $(OPT_FEATURE_FLAGS) -DSQLITE_ENABLE_BYTECODE_VTAB=1
 OPT_FEATURE_FLAGS = $(OPT_FEATURE_FLAGS) -DSQLITE_ENABLE_DESERIALIZE=1
 !ENDIF
 OPT_FEATURE_FLAGS = $(OPT_FEATURE_FLAGS) -DSQLITE_ENABLE_COLUMN_METADATA=1
@@ -1353,6 +1354,7 @@ SRC01 = \
   $(TOP)\src\vdbemem.c \
   $(TOP)\src\vdbesort.c \
   $(TOP)\src\vdbetrace.c \
+  $(TOP)\src\vdbevtab.c \
   $(TOP)\src\vtab.c \
   $(TOP)\src\wal.c \
   $(TOP)\src\walker.c \
@@ -1684,6 +1686,7 @@ FUZZCHECK_OPTS = $(FUZZCHECK_OPTS) -DSQLITE_ENABLE_FTS4
 FUZZCHECK_OPTS = $(FUZZCHECK_OPTS) -DSQLITE_ENABLE_RTREE
 FUZZCHECK_OPTS = $(FUZZCHECK_OPTS) -DSQLITE_ENABLE_GEOPOLY
 FUZZCHECK_OPTS = $(FUZZCHECK_OPTS) -DSQLITE_ENABLE_DBSTAT_VTAB
+FUZZCHECK_OPTS = $(FUZZCHECK_OPTS) -DSQLITE_ENABLE_BYTECODE_VTAB
 
 FUZZCHECK_SRC = $(TOP)\test\fuzzcheck.c $(TOP)\test\ossfuzz.c
 OSSSHELL_SRC = $(TOP)\test\ossshell.c $(TOP)\test\ossfuzz.c
@@ -2109,6 +2112,9 @@ vdbesort.lo:	$(TOP)\src\vdbesort.c $(HDR)
 vdbetrace.lo:	$(TOP)\src\vdbetrace.c $(HDR)
 	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\vdbetrace.c
 
+vdbevtab.lo:	$(TOP)\src\vdbevtab.c $(HDR)
+	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\vdbevtab.c
+
 vtab.lo:	$(TOP)\src\vtab.c $(HDR)
 	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\vtab.c
 
@@ -2353,6 +2359,7 @@ TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_SERIES_CONSTRAINT_VERIFY=1
 TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_DEFAULT_PAGE_SIZE=1024
 TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_ENABLE_STMTVTAB=1
 TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_ENABLE_DBPAGE_VTAB=1
+TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_ENABLE_BYTECODE_VTAB=1
 TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_ENABLE_JSON1=1
 TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_ENABLE_DESERIALIZE=1
 TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) $(TEST_CCONV_OPTS)

ext/fts3/fts3.c

@@ -962,6 +962,22 @@ static char *fts3WriteExprList(Fts3Table *p, const char *zFunc, int *pRc){
   return zRet;
 }
 
+/*
+** Buffer z contains a positive integer value encoded as utf-8 text.
+** Decode this value and store it in *pnOut, returning the number of bytes
+** consumed. If an overflow error occurs return a negative value.
+*/
+int sqlite3Fts3ReadInt(const char *z, int *pnOut){
+  u64 iVal = 0;
+  int i;
+  for(i=0; z[i]>='0' && z[i]<='9'; i++){
+    iVal = iVal*10 + (z[i] - '0');
+    if( iVal>0x7FFFFFFF ) return -1;
+  }
+  *pnOut = (int)iVal;
+  return i;
+}
+
 /*
 ** This function interprets the string at (*pp) as a non-negative integer
 ** value. It reads the integer and sets *pnOut to the value read, then 
@@ -977,19 +993,17 @@ static char *fts3WriteExprList(Fts3Table *p, const char *zFunc, int *pRc){
 */
 static int fts3GobbleInt(const char **pp, int *pnOut){
   const int MAX_NPREFIX = 10000000;
-  const char *p;                  /* Iterator pointer */
   int nInt = 0;                   /* Output value */
-
-  for(p=*pp; p[0]>='0' && p[0]<='9'; p++){
-    nInt = nInt * 10 + (p[0] - '0');
-    if( nInt>MAX_NPREFIX ){
-      nInt = 0;
-      break;
-    }
+  int nByte;
+  nByte = sqlite3Fts3ReadInt(*pp, &nInt);
+  if( nInt>MAX_NPREFIX ){
+    nInt = 0;
+  }
+  if( nByte==0 ){
+    return SQLITE_ERROR;
   }
-  if( p==*pp ) return SQLITE_ERROR;
   *pnOut = nInt;
-  *pp = p;
+  *pp += nByte;
   return SQLITE_OK;
 }
 

ext/fts3/fts3Int.h

@@ -591,6 +591,7 @@ int sqlite3Fts3EvalPhraseStats(Fts3Cursor *, Fts3Expr *, u32 *);
 int sqlite3Fts3FirstFilter(sqlite3_int64, char *, int, char *);
 void sqlite3Fts3CreateStatTable(int*, Fts3Table*);
 int sqlite3Fts3EvalTestDeferred(Fts3Cursor *pCsr, int *pRc);
+int sqlite3Fts3ReadInt(const char *z, int *pnOut);
 
 /* fts3_tokenizer.c */
 const char *sqlite3Fts3NextToken(const char *, int *);

ext/fts3/fts3_expr.c

@@ -446,10 +446,7 @@ static int getNextNode(
       if( pKey->eType==FTSQUERY_NEAR ){
         assert( nKey==4 );
         if( zInput[4]=='/' && zInput[5]>='0' && zInput[5]<='9' ){
-          nNear = 0;
-          for(nKey=5; zInput[nKey]>='0' && zInput[nKey]<='9'; nKey++){
-            nNear = nNear * 10 + (zInput[nKey] - '0');
-          }
+          nKey += 1+sqlite3Fts3ReadInt(&zInput[nKey+1], &nNear);
         }
       }
 

ext/fts3/fts3_write.c

@@ -3069,11 +3069,11 @@ static void fts3ReadEndBlockField(
   if( zText ){
     int i;
     int iMul = 1;
-    i64 iVal = 0;
+    u64 iVal = 0;
     for(i=0; zText[i]>='0' && zText[i]<='9'; i++){
       iVal = iVal*10 + (zText[i] - '0');
     }
-    *piEndBlock = iVal;
+    *piEndBlock = (i64)iVal;
     while( zText[i]==' ' ) i++;
     iVal = 0;
     if( zText[i]=='-' ){
@@ -3083,7 +3083,7 @@ static void fts3ReadEndBlockField(
     for(/* no-op */; zText[i]>='0' && zText[i]<='9'; i++){
       iVal = iVal*10 + (zText[i] - '0');
     }
-    *pnByte = (iVal * (i64)iMul);
+    *pnByte = ((i64)iVal * (i64)iMul);
   }
 }
 

ext/misc/cksumvfs.c

@@ -0,0 +1,778 @@
+/*
+** 2020-04-20
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file implements a VFS shim that writes a checksum on each page
+** of an SQLite database file.  When reading pages, the checksum is verified
+** and an error is raised if the checksum is incorrect.
+**
+** COMPILING
+**
+** This extension requires SQLite 3.32.0 or later.  It uses the
+** sqlite3_database_file_object() interface which was added in
+** version 3.32.0, so it will not link with an earlier version of
+** SQLite.
+**
+** To build this extension as a separately loaded shared library or
+** DLL, use compiler command-lines similar to the following:
+**
+**   (linux)    gcc -fPIC -shared cksumvfs.c -o cksumvfs.so
+**   (mac)      clang -fPIC -dynamiclib cksumvfs.c -o cksumvfs.dylib
+**   (windows)  cl cksumvfs.c -link -dll -out:cksumvfs.dll
+**
+** You may want to add additional compiler options, of course,
+** according to the needs of your project.
+**
+** If you want to statically link this extension with your product,
+** then compile it like any other C-language module but add the
+** "-DSQLITE_CKSUMVFS_STATIC" option so that this module knows that
+** it is being statically linked rather than dynamically linked
+**
+** LOADING
+**
+** To load this extension as a shared library, you first have to
+** bring up a dummy SQLite database connection to use as the argument
+** to the sqlite3_load_extension() API call.  Then you invoke the
+** sqlite3_load_extension() API and shutdown the dummy database
+** connection.  All subsequent database connections that are opened
+** will include this extension.  For example:
+**
+**     sqlite3 *db;
+**     sqlite3_open(":memory:", &db);
+**     sqlite3_load_extention(db, "./cksumvfs");
+**     sqlite3_close(db);
+**
+** If this extension is compiled with -DSQLITE_CKSUMVFS_STATIC and
+** statically linked against the application, initialize it using
+** a single API call as follows:
+**
+**     sqlite3_cksumvfs_init();
+**
+** Cksumvfs is a VFS Shim. When loaded, "cksmvfs" becomes the new
+** default VFS and it uses the prior default VFS as the next VFS
+** down in the stack.  This is normally what you want.  However, it
+** complex situations where multiple VFS shims are being loaded,
+** it might be important to ensure that cksumvfs is loaded in the
+** correct order so that it sequences itself into the default VFS
+** Shim stack in the right order.
+**
+** USING
+**
+** Open database connections using the sqlite3_open() or 
+** sqlite3_open_v2() interfaces, as normal.  Ordinary database files
+** (without a checksum) will operate normally.  Databases with 
+** checksums will return an SQLITE_IOERR_DATA error if a page is
+** encountered that contains an invalid checksum.
+**
+** Checksumming only works on databases that have a reserve-bytes
+** value of exactly 8.  The default value for reserve-bytes is 0.
+** Hence, newly created database files will omit the checksum by
+** default.  To create a database that includes a checksum, change
+** the reserve-bytes value to 8 by runing:
+**
+**    int n = 8;
+**    sqlite3_file_control(db, 0, SQLITE_FCNTL_RESERVED_BYTES, &n);
+**
+** If you do this immediately after creating a new database file,
+** before anything else has been written into the file, then that
+** might be all that you need to do.  Otherwise, the API call
+** above should be followed by:
+**
+**    sqlite3_exec(db, "VACUUM", 0, 0, 0);
+**
+** It never hurts to run the VACUUM, even if you don't need it.
+** If the database is in WAL mode, you should shutdown and
+** reopen all database connections before continuing.
+**
+** From the CLI, use the ".filectrl reserve_bytes 8" command, 
+** followed by "VACUUM;".
+**
+** Note that SQLite allows the number of reserve-bytes to be
+** increased but not decreased.  So if a database file already
+** has a reserve-bytes value greater than 8, there is no way to
+** activate checksumming on that database, other than to dump
+** and restore the database file.  Note also that other extensions
+** might also make use of the reserve-bytes.  Checksumming will
+** be incompatible with those other extensions.
+**
+** VERIFICATION OF CHECKSUMS
+**
+** If any checksum is incorrect, the "PRAGMA quick_check" command
+** will find it.  To verify that checksums are actually enabled
+** and running, use the following query:
+**
+**   SELECT count(*), verify_checksum(data)
+**     FROM sqlite_dbpage
+**    GROUP BY 2;
+**
+** There are three possible outputs form the verify_checksum()
+** function: 1, 0, and NULL.  1 is returned if the checksum is
+** correct.  0 is returned if the checksum is incorrect.  NULL
+** is returned if the page is unreadable.  If checksumming is
+** enabled, the read will fail if the checksum is wrong, so the
+** usual result from verify_checksum() on a bad checksum is NULL.
+**
+** If everything is OK, the query above should return a single
+** row where the second column is 1.  Any other result indicates
+** either that there is a checksum error, or checksum validation
+** is disabled.
+**
+** CONTROLLING CHECKSUM VERIFICATION
+**
+** The cksumvfs extension implements a new PRAGMA statement that can
+** be used to disable, re-enable, or query the status of checksum
+** verification:
+**
+**    PRAGMA checksum_verification;          -- query status
+**    PRAGMA checksum_verification=OFF;      -- disable verification
+**    PRAGMA checksum_verification=ON;       -- re-enable verification
+**
+** The "checksum_verification" pragma will return "1" (true) or "0"
+** (false) if checksum verification is enabled or disabled, respectively.
+** "Verification" in this context means the feature that causes
+** SQLITE_IOERR_DATA errors if a checksum mismatch is detected while
+** reading.  Checksums are always kept up-to-date as long as the
+** reserve-bytes value of the database is 8, regardless of the setting
+** of this pragma.  Checksum verification can be disabled (for example)
+** to do forensic analysis of a database that has previously reported
+** a checksum error.
+**
+** The "checksum_verification" pragma will always respond with "0" if
+** the database file does not have a reserve-bytes value of 8.  The
+** pragma will return no rows at all if the cksumvfs extension is
+** not loaded.
+**
+** IMPLEMENTATION NOTES
+**
+** The checksum is stored in the last 8 bytes of each page.  This
+** module only operates if the "bytes of reserved space on each page"
+** value at offset 20 the SQLite database header is exactly 8.  If
+** the reserved-space value is not 8, this module is a no-op.
+*/
+#ifdef SQLITE_CKSUMVFS_STATIC
+# include "sqlite3.h"
+#else
+# include "sqlite3ext.h"
+  SQLITE_EXTENSION_INIT1
+#endif
+#include <string.h>
+#include <assert.h>
+
+
+/*
+** Forward declaration of objects used by this utility
+*/
+typedef struct sqlite3_vfs CksmVfs;
+typedef struct CksmFile CksmFile;
+
+/*
+** Useful datatype abbreviations
+*/
+#if !defined(SQLITE_CORE)
+  typedef unsigned char u8;
+  typedef unsigned int u32;
+#endif
+
+/* Access to a lower-level VFS that (might) implement dynamic loading,
+** access to randomness, etc.
+*/
+#define ORIGVFS(p)  ((sqlite3_vfs*)((p)->pAppData))
+#define ORIGFILE(p) ((sqlite3_file*)(((CksmFile*)(p))+1))
+
+/* An open file */
+struct CksmFile {
+  sqlite3_file base;    /* IO methods */
+  const char *zFName;   /* Original name of the file */
+  char computeCksm;     /* True to compute checksums.
+                        ** Always true if reserve size is 8. */
+  char verifyCksm;      /* True to verify checksums */
+  char isWal;           /* True if processing a WAL file */
+  CksmFile *pPartner;   /* Ptr from WAL to main-db, or from main-db to WAL */
+};
+
+/*
+** Methods for CksmFile
+*/
+static int cksmClose(sqlite3_file*);
+static int cksmRead(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
+static int cksmWrite(sqlite3_file*,const void*,int iAmt, sqlite3_int64 iOfst);
+static int cksmTruncate(sqlite3_file*, sqlite3_int64 size);
+static int cksmSync(sqlite3_file*, int flags);
+static int cksmFileSize(sqlite3_file*, sqlite3_int64 *pSize);
+static int cksmLock(sqlite3_file*, int);
+static int cksmUnlock(sqlite3_file*, int);
+static int cksmCheckReservedLock(sqlite3_file*, int *pResOut);
+static int cksmFileControl(sqlite3_file*, int op, void *pArg);
+static int cksmSectorSize(sqlite3_file*);
+static int cksmDeviceCharacteristics(sqlite3_file*);
+static int cksmShmMap(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
+static int cksmShmLock(sqlite3_file*, int offset, int n, int flags);
+static void cksmShmBarrier(sqlite3_file*);
+static int cksmShmUnmap(sqlite3_file*, int deleteFlag);
+static int cksmFetch(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
+static int cksmUnfetch(sqlite3_file*, sqlite3_int64 iOfst, void *p);
+
+/*
+** Methods for CksmVfs
+*/
+static int cksmOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *);
+static int cksmDelete(sqlite3_vfs*, const char *zName, int syncDir);
+static int cksmAccess(sqlite3_vfs*, const char *zName, int flags, int *);
+static int cksmFullPathname(sqlite3_vfs*, const char *zName, int, char *zOut);
+static void *cksmDlOpen(sqlite3_vfs*, const char *zFilename);
+static void cksmDlError(sqlite3_vfs*, int nByte, char *zErrMsg);
+static void (*cksmDlSym(sqlite3_vfs *pVfs, void *p, const char*zSym))(void);
+static void cksmDlClose(sqlite3_vfs*, void*);
+static int cksmRandomness(sqlite3_vfs*, int nByte, char *zOut);
+static int cksmSleep(sqlite3_vfs*, int microseconds);
+static int cksmCurrentTime(sqlite3_vfs*, double*);
+static int cksmGetLastError(sqlite3_vfs*, int, char *);
+static int cksmCurrentTimeInt64(sqlite3_vfs*, sqlite3_int64*);
+static int cksmSetSystemCall(sqlite3_vfs*, const char*,sqlite3_syscall_ptr);
+static sqlite3_syscall_ptr cksmGetSystemCall(sqlite3_vfs*, const char *z);
+static const char *cksmNextSystemCall(sqlite3_vfs*, const char *zName);
+
+static sqlite3_vfs cksm_vfs = {
+  3,                            /* iVersion (set when registered) */
+  0,                            /* szOsFile (set when registered) */
+  1024,                         /* mxPathname */
+  0,                            /* pNext */
+  "cksmvfs",                    /* zName */
+  0,                            /* pAppData (set when registered) */ 
+  cksmOpen,                     /* xOpen */
+  cksmDelete,                   /* xDelete */
+  cksmAccess,                   /* xAccess */
+  cksmFullPathname,             /* xFullPathname */
+  cksmDlOpen,                   /* xDlOpen */
+  cksmDlError,                  /* xDlError */
+  cksmDlSym,                    /* xDlSym */
+  cksmDlClose,                  /* xDlClose */
+  cksmRandomness,               /* xRandomness */
+  cksmSleep,                    /* xSleep */
+  cksmCurrentTime,              /* xCurrentTime */
+  cksmGetLastError,             /* xGetLastError */
+  cksmCurrentTimeInt64,         /* xCurrentTimeInt64 */
+  cksmSetSystemCall,            /* xSetSystemCall */
+  cksmGetSystemCall,            /* xGetSystemCall */
+  cksmNextSystemCall            /* xNextSystemCall */
+};
+
+static const sqlite3_io_methods cksm_io_methods = {
+  3,                              /* iVersion */
+  cksmClose,                      /* xClose */
+  cksmRead,                       /* xRead */
+  cksmWrite,                      /* xWrite */
+  cksmTruncate,                   /* xTruncate */
+  cksmSync,                       /* xSync */
+  cksmFileSize,                   /* xFileSize */
+  cksmLock,                       /* xLock */
+  cksmUnlock,                     /* xUnlock */
+  cksmCheckReservedLock,          /* xCheckReservedLock */
+  cksmFileControl,                /* xFileControl */
+  cksmSectorSize,                 /* xSectorSize */
+  cksmDeviceCharacteristics,      /* xDeviceCharacteristics */
+  cksmShmMap,                     /* xShmMap */
+  cksmShmLock,                    /* xShmLock */
+  cksmShmBarrier,                 /* xShmBarrier */
+  cksmShmUnmap,                   /* xShmUnmap */
+  cksmFetch,                      /* xFetch */
+  cksmUnfetch                     /* xUnfetch */
+};
+
+/* Do byte swapping on a unsigned 32-bit integer */
+#define BYTESWAP32(x) ( \
+    (((x)&0x000000FF)<<24) + (((x)&0x0000FF00)<<8)  \
+  + (((x)&0x00FF0000)>>8)  + (((x)&0xFF000000)>>24) \
+)
+
+/* Compute a checksum on a buffer */
+static void cksmCompute(
+  u8 *a,           /* Content to be checksummed */
+  int nByte,       /* Bytes of content in a[].  Must be a multiple of 8. */
+  u8 *aOut         /* OUT: Final 8-byte checksum value output */
+){
+  u32 s1 = 0, s2 = 0;
+  u32 *aData = (u32*)a;
+  u32 *aEnd = (u32*)&a[nByte];
+  u32 x = 1;
+
+  assert( nByte>=8 );
+  assert( (nByte&0x00000007)==0 );
+  assert( nByte<=65536 );
+
+  if( 1 == *(u8*)&x ){
+    /* Little-endian */
+    do {
+      s1 += *aData++ + s2;
+      s2 += *aData++ + s1;
+    }while( aData<aEnd );
+  }else{
+    /* Big-endian */
+    do {
+      s1 += BYTESWAP32(aData[0]) + s2;
+      s2 += BYTESWAP32(aData[1]) + s1;
+      aData += 2;
+    }while( aData<aEnd );
+    s1 = BYTESWAP32(s1);
+    s2 = BYTESWAP32(s2);
+  }
+  memcpy(aOut, &s1, 4);
+  memcpy(aOut+4, &s2, 4);
+}
+
+/*
+** SQL function:    verify_checksum(BLOB)
+**
+** Return 0 or 1 if the checksum is invalid or valid.  Or return
+** NULL if the input is not a BLOB that is the right size for a
+** database page.
+*/
+static void cksmVerifyFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  int nByte;
+  u8 *data;
+  u8 cksum[8];
+  data = (u8*)sqlite3_value_blob(argv[0]);
+  if( data==0 ) return;
+  if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ) return;
+  nByte = sqlite3_value_bytes(argv[0]);
+  if( nByte<512 || nByte>65536 || (nByte & (nByte-1))!=0 ) return;
+  cksmCompute(data, nByte-8, cksum);
+  sqlite3_result_int(context, memcmp(data+nByte-8,cksum,8)==0);
+}
+
+/*
+** Close a cksm-file.
+*/
+static int cksmClose(sqlite3_file *pFile){
+  CksmFile *p = (CksmFile *)pFile;
+  if( p->pPartner ){
+    assert( p->pPartner->pPartner==p );
+    p->pPartner->pPartner = 0;
+    p->pPartner = 0;
+  }
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xClose(pFile);
+}
+
+/*
+** Read data from a cksm-file.
+*/
+static int cksmRead(
+  sqlite3_file *pFile, 
+  void *zBuf, 
+  int iAmt, 
+  sqlite_int64 iOfst
+){
+  int rc;
+  CksmFile *p = (CksmFile *)pFile;
+  pFile = ORIGFILE(pFile);
+  rc = pFile->pMethods->xRead(pFile, zBuf, iAmt, iOfst);
+  if( rc==SQLITE_OK ){
+    if( iOfst==0 && iAmt>=100 && memcmp(zBuf,"SQLite format 3",16)==0 ){
+      u8 *d = (u8*)zBuf;
+      char hasCorrectReserveSize = (d[20]==8);
+      if( hasCorrectReserveSize!=p->computeCksm ){
+        p->computeCksm = p->verifyCksm = hasCorrectReserveSize;
+      }
+    }
+    /* Verify the checksum if (1) the size seems appropriate for a database
+    ** page, and if (2) checksum verification is enabled.  But (3) do not 
+    ** verify the checksums on a WAL page if the main database file
+    ** has subsequently turned off checksums.
+    */
+    if( iAmt>=512           /* (1) */
+     && p->verifyCksm       /* (2) */
+     && (!p->isWal || (p->pPartner!=0 && p->pPartner->verifyCksm))  /* (3) */
+    ){
+      u8 cksum[8];
+      cksmCompute((u8*)zBuf, iAmt-8, cksum);
+      if( memcmp(zBuf+iAmt-8, cksum, 8)!=0 ){
+        sqlite3_log(SQLITE_IOERR_DATA,
+           "checksum fault offset %lld of \"%s\"",
+           iOfst, p->zFName);
+        rc = SQLITE_IOERR_DATA;
+      }
+    }
+  }
+  return rc;
+}
+
+/*
+** Write data to a cksm-file.
+*/
+static int cksmWrite(
+  sqlite3_file *pFile,
+  const void *zBuf,
+  int iAmt,
+  sqlite_int64 iOfst
+){
+  CksmFile *p = (CksmFile *)pFile;
+  pFile = ORIGFILE(pFile);
+  if( iOfst==0 && iAmt>=100 && memcmp(zBuf,"SQLite format 3",16)==0 ){
+    u8 *d = (u8*)zBuf;
+    char hasCorrectReserveSize = (d[20]==8);
+    if( hasCorrectReserveSize!=p->computeCksm ){
+      p->computeCksm = p->verifyCksm = hasCorrectReserveSize;
+    }
+  }
+  /* If the write size is appropriate for a database page and if
+  ** checksums where ever enabled, then it will be safe to compute
+  ** the checksums.  The reserve byte size might have increased, but
+  ** it will never decrease.  And because it cannot decrease, the
+  ** checksum will not overwrite anything.
+  */
+  if( iAmt>=512 && p->computeCksm ){
+    cksmCompute((u8*)zBuf, iAmt-8, ((u8*)zBuf)+iAmt-8);
+  }
+  return pFile->pMethods->xWrite(pFile, zBuf, iAmt, iOfst);
+}
+
+/*
+** Truncate a cksm-file.
+*/
+static int cksmTruncate(sqlite3_file *pFile, sqlite_int64 size){
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xTruncate(pFile, size);
+}
+
+/*
+** Sync a cksm-file.
+*/
+static int cksmSync(sqlite3_file *pFile, int flags){
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xSync(pFile, flags);
+}
+
+/*
+** Return the current file-size of a cksm-file.
+*/
+static int cksmFileSize(sqlite3_file *pFile, sqlite_int64 *pSize){
+  CksmFile *p = (CksmFile *)pFile;
+  pFile = ORIGFILE(p);
+  return pFile->pMethods->xFileSize(pFile, pSize);
+}
+
+/*
+** Lock a cksm-file.
+*/
+static int cksmLock(sqlite3_file *pFile, int eLock){
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xLock(pFile, eLock);
+}
+
+/*
+** Unlock a cksm-file.
+*/
+static int cksmUnlock(sqlite3_file *pFile, int eLock){
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xUnlock(pFile, eLock);
+}
+
+/*
+** Check if another file-handle holds a RESERVED lock on a cksm-file.
+*/
+static int cksmCheckReservedLock(sqlite3_file *pFile, int *pResOut){
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xCheckReservedLock(pFile, pResOut);
+}
+
+/*
+** File control method. For custom operations on a cksm-file.
+*/
+static int cksmFileControl(sqlite3_file *pFile, int op, void *pArg){
+  int rc;
+  CksmFile *p = (CksmFile*)pFile;
+  pFile = ORIGFILE(pFile);
+  if( op==SQLITE_FCNTL_PRAGMA ){
+    char **azArg = (char**)pArg;
+    assert( azArg[1]!=0 );
+    if( sqlite3_stricmp(azArg[1],"checksum_verification")==0 ){
+      char *zArg = azArg[2];
+      if( zArg!=0 ){
+        if( (zArg[0]>='1' && zArg[0]<='9')
+         || sqlite3_strlike("enable%",zArg,0)==0
+         || sqlite3_stricmp("yes",zArg)==0
+         || sqlite3_stricmp("on",zArg)==0
+        ){
+          p->verifyCksm = p->computeCksm;
+        }else{
+          p->verifyCksm = 0;
+        }
+      }
+      azArg[0] = sqlite3_mprintf("%d",p->verifyCksm);
+      return SQLITE_OK;
+    }else if( p->computeCksm && azArg[2]!=0
+           && sqlite3_stricmp(azArg[1], "page_size")==0 ){
+      /* Do not allow page size changes on a checksum database */
+      return SQLITE_OK;
+    }
+  }
+  rc = pFile->pMethods->xFileControl(pFile, op, pArg);
+  if( rc==SQLITE_OK && op==SQLITE_FCNTL_VFSNAME ){
+    *(char**)pArg = sqlite3_mprintf("cksm/%z", *(char**)pArg);
+  }
+  return rc;
+}
+
+/*
+** Return the sector-size in bytes for a cksm-file.
+*/
+static int cksmSectorSize(sqlite3_file *pFile){
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xSectorSize(pFile);
+}
+
+/*
+** Return the device characteristic flags supported by a cksm-file.
+*/
+static int cksmDeviceCharacteristics(sqlite3_file *pFile){
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xDeviceCharacteristics(pFile);
+}
+
+/* Create a shared memory file mapping */
+static int cksmShmMap(
+  sqlite3_file *pFile,
+  int iPg,
+  int pgsz,
+  int bExtend,
+  void volatile **pp
+){
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xShmMap(pFile,iPg,pgsz,bExtend,pp);
+}
+
+/* Perform locking on a shared-memory segment */
+static int cksmShmLock(sqlite3_file *pFile, int offset, int n, int flags){
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xShmLock(pFile,offset,n,flags);
+}
+
+/* Memory barrier operation on shared memory */
+static void cksmShmBarrier(sqlite3_file *pFile){
+  pFile = ORIGFILE(pFile);
+  pFile->pMethods->xShmBarrier(pFile);
+}
+
+/* Unmap a shared memory segment */
+static int cksmShmUnmap(sqlite3_file *pFile, int deleteFlag){
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xShmUnmap(pFile,deleteFlag);
+}
+
+/* Fetch a page of a memory-mapped file */
+static int cksmFetch(
+  sqlite3_file *pFile,
+  sqlite3_int64 iOfst,
+  int iAmt,
+  void **pp
+){
+  CksmFile *p = (CksmFile *)pFile;
+  if( p->computeCksm ){
+    *pp = 0;
+    return SQLITE_OK;
+  }
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xFetch(pFile, iOfst, iAmt, pp);
+}
+
+/* Release a memory-mapped page */
+static int cksmUnfetch(sqlite3_file *pFile, sqlite3_int64 iOfst, void *pPage){
+  pFile = ORIGFILE(pFile);
+  return pFile->pMethods->xUnfetch(pFile, iOfst, pPage);
+}
+
+/*
+** Open a cksm file handle.
+*/
+static int cksmOpen(
+  sqlite3_vfs *pVfs,
+  const char *zName,
+  sqlite3_file *pFile,
+  int flags,
+  int *pOutFlags
+){
+  CksmFile *p;
+  sqlite3_file *pSubFile;
+  sqlite3_vfs *pSubVfs;
+  int rc;
+  pSubVfs = ORIGVFS(pVfs);
+  if( (flags & (SQLITE_OPEN_MAIN_DB|SQLITE_OPEN_WAL))==0 ){
+    return pSubVfs->xOpen(pSubVfs, zName, pFile, flags, pOutFlags);
+  }
+  p = (CksmFile*)pFile;
+  memset(p, 0, sizeof(*p));
+  pSubFile = ORIGFILE(pFile);
+  p->base.pMethods = &cksm_io_methods;
+  rc = pSubVfs->xOpen(pSubVfs, zName, pSubFile, flags, pOutFlags);
+  if( rc ) goto cksm_open_done;
+  if( flags & SQLITE_OPEN_WAL ){
+    sqlite3_file *pDb = sqlite3_database_file_object(zName);
+    p->pPartner = (CksmFile*)pDb;
+    assert( p->pPartner->pPartner==0 );
+    p->pPartner->pPartner = p;
+    p->isWal = 1;
+    p->computeCksm = p->pPartner->computeCksm;
+  }else{
+    p->isWal = 0;
+    p->computeCksm = 0;
+  }
+  p->zFName = zName;
+cksm_open_done:
+  if( rc ) pFile->pMethods = 0;
+  return rc;
+}
+
+/*
+** All other VFS methods are pass-thrus.
+*/
+static int cksmDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
+  return ORIGVFS(pVfs)->xDelete(ORIGVFS(pVfs), zPath, dirSync);
+}
+static int cksmAccess(
+  sqlite3_vfs *pVfs, 
+  const char *zPath, 
+  int flags, 
+  int *pResOut
+){
+  return ORIGVFS(pVfs)->xAccess(ORIGVFS(pVfs), zPath, flags, pResOut);
+}
+static int cksmFullPathname(
+  sqlite3_vfs *pVfs, 
+  const char *zPath, 
+  int nOut, 
+  char *zOut
+){
+  return ORIGVFS(pVfs)->xFullPathname(ORIGVFS(pVfs),zPath,nOut,zOut);
+}
+static void *cksmDlOpen(sqlite3_vfs *pVfs, const char *zPath){
+  return ORIGVFS(pVfs)->xDlOpen(ORIGVFS(pVfs), zPath);
+}
+static void cksmDlError(sqlite3_vfs *pVfs, int nByte, char *zErrMsg){
+  ORIGVFS(pVfs)->xDlError(ORIGVFS(pVfs), nByte, zErrMsg);
+}
+static void (*cksmDlSym(sqlite3_vfs *pVfs, void *p, const char *zSym))(void){
+  return ORIGVFS(pVfs)->xDlSym(ORIGVFS(pVfs), p, zSym);
+}
+static void cksmDlClose(sqlite3_vfs *pVfs, void *pHandle){
+  ORIGVFS(pVfs)->xDlClose(ORIGVFS(pVfs), pHandle);
+}
+static int cksmRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
+  return ORIGVFS(pVfs)->xRandomness(ORIGVFS(pVfs), nByte, zBufOut);
+}
+static int cksmSleep(sqlite3_vfs *pVfs, int nMicro){
+  return ORIGVFS(pVfs)->xSleep(ORIGVFS(pVfs), nMicro);
+}
+static int cksmCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){
+  return ORIGVFS(pVfs)->xCurrentTime(ORIGVFS(pVfs), pTimeOut);
+}
+static int cksmGetLastError(sqlite3_vfs *pVfs, int a, char *b){
+  return ORIGVFS(pVfs)->xGetLastError(ORIGVFS(pVfs), a, b);
+}
+static int cksmCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *p){
+  return ORIGVFS(pVfs)->xCurrentTimeInt64(ORIGVFS(pVfs), p);
+}
+static int cksmSetSystemCall(
+  sqlite3_vfs *pVfs,
+  const char *zName,
+  sqlite3_syscall_ptr pCall
+){
+  return ORIGVFS(pVfs)->xSetSystemCall(ORIGVFS(pVfs),zName,pCall);
+}
+static sqlite3_syscall_ptr cksmGetSystemCall(
+  sqlite3_vfs *pVfs,
+  const char *zName
+){
+  return ORIGVFS(pVfs)->xGetSystemCall(ORIGVFS(pVfs),zName);
+}
+static const char *cksmNextSystemCall(sqlite3_vfs *pVfs, const char *zName){
+  return ORIGVFS(pVfs)->xNextSystemCall(ORIGVFS(pVfs), zName);
+}
+
+/* Register the verify_checksum() SQL function.
+*/
+static int cksmRegisterFunc(
+  sqlite3 *db, 
+  char **pzErrMsg, 
+  const sqlite3_api_routines *pApi
+){
+  int rc;
+  if( db==0 ) return SQLITE_OK;
+  rc = sqlite3_create_function(db, "verify_checksum", 1,
+                   SQLITE_UTF8|SQLITE_INNOCUOUS|SQLITE_DETERMINISTIC,
+                   0, cksmVerifyFunc, 0, 0);
+  return rc;
+}
+
+/*
+** Register the cksum VFS as the default VFS for the system.
+** Also make arrangements to automatically register the "verify_checksum()"
+** SQL function on each new database connection.
+*/
+static int cksmRegisterVfs(void){
+  int rc = SQLITE_OK;
+  sqlite3_vfs *pOrig;
+  if( sqlite3_vfs_find("cksum")!=0 ) return SQLITE_OK;
+  pOrig = sqlite3_vfs_find(0);
+  cksm_vfs.iVersion = pOrig->iVersion;
+  cksm_vfs.pAppData = pOrig;
+  cksm_vfs.szOsFile = pOrig->szOsFile + sizeof(CksmFile);
+  rc = sqlite3_vfs_register(&cksm_vfs, 1);
+  if( rc==SQLITE_OK ){
+    rc = sqlite3_auto_extension((void(*)(void))cksmRegisterFunc);
+  }
+  return rc;
+}
+
+#if defined(SQLITE_CKSUMVFS_STATIC)
+/* This variant of the initializer runs when the extension is
+** statically linked.
+*/
+int sqlite3_register_cksumvfs(const char *NotUsed){
+  (void)NotUsed;
+  return cksmRegisterVfs();
+}
+#endif /* defined(SQLITE_CKSUMVFS_STATIC */
+
+#if !defined(SQLITE_CKSUMVFS_STATIC)
+/* This variant of the initializer function is used when the
+** extension is shared library to be loaded at run-time.
+*/
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+/* 
+** This routine is called by sqlite3_load_extension() when the
+** extension is first loaded.
+***/
+int sqlite3_cksumvfs_init(
+  sqlite3 *db, 
+  char **pzErrMsg, 
+  const sqlite3_api_routines *pApi
+){
+  int rc;
+  SQLITE_EXTENSION_INIT2(pApi);
+  (void)pzErrMsg; /* not used */
+  rc = cksmRegisterFunc(db, 0, 0);
+  if( rc==SQLITE_OK ){
+    
+  }
+  if( rc==SQLITE_OK ){
+    rc = cksmRegisterVfs();
+  }
+  if( rc==SQLITE_OK ) rc = SQLITE_OK_LOAD_PERMANENTLY;
+  return rc;
+}
+#endif /* !defined(SQLITE_CKSUMVFS_STATIC) */

main.mk

@@ -74,7 +74,8 @@ LIBOBJ+= vdbe.o parse.o \
          table.o threads.o tokenize.o treeview.o trigger.o \
          update.o upsert.o userauth.o util.o vacuum.o \
          vdbeapi.o vdbeaux.o vdbeblob.o vdbemem.o vdbesort.o \
-	 vdbetrace.o wal.o walker.o where.o wherecode.o whereexpr.o \
+	 vdbetrace.o vdbevtab.o \
+         wal.o walker.o where.o wherecode.o whereexpr.o \
          utf.o vtab.o window.o
 
 LIBOBJ += sqlite3session.o
@@ -173,6 +174,7 @@ SRC = \
   $(TOP)/src/vdbemem.c \
   $(TOP)/src/vdbesort.c \
   $(TOP)/src/vdbetrace.c \
+  $(TOP)/src/vdbevtab.c \
   $(TOP)/src/vdbeInt.h \
   $(TOP)/src/vtab.c \
   $(TOP)/src/vxworks.h \
@@ -526,6 +528,7 @@ SHELL_OPT += -DSQLITE_ENABLE_UNKNOWN_SQL_FUNCTION
 SHELL_OPT += -DSQLITE_ENABLE_STMTVTAB
 SHELL_OPT += -DSQLITE_ENABLE_DBPAGE_VTAB
 SHELL_OPT += -DSQLITE_ENABLE_DBSTAT_VTAB
+SHELL_OPT += -DSQLITE_ENABLE_BYTECODE_VTAB
 SHELL_OPT += -DSQLITE_ENABLE_OFFSET_SQL_FUNC
 FUZZERSHELL_OPT = -DSQLITE_ENABLE_JSON1
 FUZZCHECK_OPT = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_MEMSYS5
@@ -536,6 +539,7 @@ FUZZCHECK_OPT += -DSQLITE_ENABLE_FTS4
 FUZZCHECK_OPT += -DSQLITE_ENABLE_RTREE
 FUZZCHECK_OPT += -DSQLITE_ENABLE_GEOPOLY
 FUZZCHECK_OPT += -DSQLITE_ENABLE_DBSTAT_VTAB
+FUZZCHECK_OPT += -DSQLITE_ENABLE_BYTECODE_VTAB
 DBFUZZ_OPT =
 KV_OPT = -DSQLITE_THREADSAFE=0 -DSQLITE_DIRECT_OVERFLOW_READ
 ST_OPT = -DSQLITE_THREADSAFE=0
@@ -586,6 +590,7 @@ DBFUZZ2_OPTS = \
   -DSQLITE_ENABLE_DESERIALIZE \
   -DSQLITE_DEBUG \
   -DSQLITE_ENABLE_DBSTAT_VTAB \
+  -DSQLITE_ENABLE_BYTECODE_VTAB \
   -DSQLITE_ENABLE_RTREE \
   -DSQLITE_ENABLE_FTS4 \
   -DSQLITE_ENABLE_FTS5
@@ -895,6 +900,7 @@ TESTFIXTURE_FLAGS += -DSQLITE_SERIES_CONSTRAINT_VERIFY=1
 TESTFIXTURE_FLAGS += -DSQLITE_DEFAULT_PAGE_SIZE=1024
 TESTFIXTURE_FLAGS += -DSQLITE_ENABLE_STMTVTAB
 TESTFIXTURE_FLAGS += -DSQLITE_ENABLE_DBPAGE_VTAB
+TESTFIXTURE_FLAGS += -DSQLITE_ENABLE_BYTECODE_VTAB
 TESTFIXTURE_FLAGS += -DTCLSH_INIT_PROC=sqlite3TestInit
 
 testfixture$(EXE): $(TESTSRC2) libsqlite3.a $(TESTSRC) $(TOP)/src/tclsqlite.c

manifest

@@ -1,11 +1,11 @@
-C Add\sthe\ssqlite3_database_file_object()\sinterface\sto\ssqlite3ext.h.
-D 2020-04-21T19:27:08.207
+C Corner-case\schanges\sto\sthe\sbytecode\svirtual\stable\sfor\stestability\sand\ncorrectness.
+D 2020-05-02T00:01:39.619
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
-F Makefile.in f6ab6e307d31e09d82aa4eca87ccb21ce66f486279e204b54b3149ff0d71616f
+F Makefile.in 280cf54350738dfd567bd97ae1bff1bf68c64658c4d5ff21be9cae117e92f063
 F Makefile.linux-gcc f609543700659711fbd230eced1f01353117621dccae7b9fb70daa64236c5241
-F Makefile.msc 46c338b1151fbeed42c82416c6bc4da7ff9a10f851bf379f8592280fd53d6efa
+F Makefile.msc d9232f9339da7d2b82611cb148734d36be4cc90e17a968882e71d9bf75e512df
 F README.md 1514a365ffca3c138e00c5cc839906108a01011a6b082bad19b09781e3aa498a
 F VERSION 980d78a2ce04a1fd0ebefbaabd665f7f9186563820629ee29c6e350e96f19b52
 F aclocal.m4 a5c22d164aff7ed549d53a90fa56d56955281f50
@@ -82,11 +82,11 @@ F ext/fts3/README.content fdc666a70d5257a64fee209f97cf89e0e6e32b51
 F ext/fts3/README.syntax a19711dc5458c20734b8e485e75fb1981ec2427a
 F ext/fts3/README.tokenizers b92bdeb8b46503f0dd301d364efc5ef59ef9fa8e2758b8e742f39fa93a2e422d
 F ext/fts3/README.txt 8c18f41574404623b76917b9da66fcb0ab38328d
-F ext/fts3/fts3.c 2a9dd452003a143248e68449302da80dd0c43df72195b56577e3562e43c408a0
+F ext/fts3/fts3.c de2cc136ccc6128e948ffd5d74636756014b2430d6237d7002c3bc3ceb1ae3ae
 F ext/fts3/fts3.h 3a10a0af180d502cecc50df77b1b22df142817fe
-F ext/fts3/fts3Int.h f091030b976045e7df91af2337935952b477cdbd9f48058c44c965684484cb50
+F ext/fts3/fts3Int.h 2c59cc46aefde134c1782e89a6a5384710ddcd4e783071337aa5d43d07269be3
 F ext/fts3/fts3_aux.c 96708c8b3a7d9b8ca1b68ea2b7e503e283f20e95f145becadedfad096dbd0f34
-F ext/fts3/fts3_expr.c b132af223e90e35b9f9efa9fe63d6ae737d34153a3b6066736086df8abc78a1f
+F ext/fts3/fts3_expr.c f081e38da641724cd72c20e23b71db2bf4d0c9517c14637442f6910259f11a34
 F ext/fts3/fts3_hash.c 8b6e31bfb0844c27dc6092c2620bdb1fca17ed613072db057d96952c6bdb48b7
 F ext/fts3/fts3_hash.h 39cf6874dc239d6b4e30479b1975fe5b22a3caaf
 F ext/fts3/fts3_icu.c 305ce7fb6036484085b5556a9c8e62acdc7763f0f4cdf5fd538212a9f3720116
@@ -100,7 +100,7 @@ F ext/fts3/fts3_tokenizer.h 64c6ef6c5272c51ebe60fc607a896e84288fcbc3
 F ext/fts3/fts3_tokenizer1.c 5c98225a53705e5ee34824087478cf477bdb7004
 F ext/fts3/fts3_unicode.c 4b9af6151c29b35ed09574937083cece7c31e911f69615e168a39677569b684d
 F ext/fts3/fts3_unicode2.c 416eb7e1e81142703520d284b768ca2751d40e31fa912cae24ba74860532bf0f
-F ext/fts3/fts3_write.c d5da5f010b2e2c1523f0e359ec43858bb724f608d3805d0e2a82ca2b466eb22e
+F ext/fts3/fts3_write.c ed869b24d074f2498bdbef915d6db1f88c604ca5811502112061932a0bed5133
 F ext/fts3/fts3speed.tcl b54caf6a18d38174f1a6e84219950d85e98bb1e9
 F ext/fts3/mkfts3amal.tcl 252ecb7fe6467854f2aa237bf2c390b74e71f100
 F ext/fts3/tool/fts3cov.sh c331d006359456cf6f8f953e37f2b9c7d568f3863f00bb5f7eb87fea4ac01b73
@@ -285,6 +285,7 @@ F ext/misc/appendvfs.c 3777f22ec1057dc4e5fd89f2fbddcc7a29fbeef1ad038c736c54411bb
 F ext/misc/blobio.c a867c4c4617f6ec223a307ebfe0eabb45e0992f74dd47722b96f3e631c0edb2a
 F ext/misc/btreeinfo.c 26004b7a6be320ec08fc20ca8d0f01fccb00a98cbe0f3197446794ff2a506aa3
 F ext/misc/carray.c 91e9a7f512fda934894bed30464552fffa7d3073b5be04189ae0bd0c59f26bfd
+F ext/misc/cksumvfs.c 755627c9112a000bc89653cb5038e080e69c58fa0a5c8e9ebd747f24e5fc01c9
 F ext/misc/closure.c dbfd8543b2a017ae6b1a5843986b22ddf99ff126ec9634a2f4047cd14c85c243
 F ext/misc/completion.c a0efe03edfdc4f717c61e6c9b0bfe2708ff7878010dae3174980a68fdf76aabc
 F ext/misc/compress.c 3354c77a7c8e86e07d849916000cdac451ed96500bfb5bd83b20eb61eee012c9
@@ -454,7 +455,7 @@ F ext/userauth/userauth.c 7f00cded7dcaa5d47f54539b290a43d2e59f4b1eb5f447545fa865
 F install-sh 9d4de14ab9fb0facae2f48780b874848cbf2f895 x
 F ltmain.sh 3ff0879076df340d2e23ae905484d8c15d5fdea8
 F magic.txt 8273bf49ba3b0c8559cb2774495390c31fd61c60
-F main.mk f3a972451ed68fa1101d81606a2a1b0a2600b85547059fe89ccb2380b983e50c
+F main.mk 0c20162946c82e216ae3abab6334d52f1c9b09035c13619ade404b5e7fe3ce21
 F mkso.sh fd21c06b063bb16a5d25deea1752c2da6ac3ed83
 F mptest/config01.test 3c6adcbc50b991866855f1977ff172eb6d901271
 F mptest/config02.test 4415dfe36c48785f751e16e32c20b077c28ae504
@@ -473,18 +474,18 @@ F src/auth.c a3d5bfdba83d25abed1013a8c7a5f204e2e29b0c25242a56bc02bb0c07bf1e06
 F src/backup.c 5e617c087f1c2d6005c2ec694ce80d6e16bc68d906e1b1c556d7c7c2228b636b
 F src/bitvec.c 17ea48eff8ba979f1f5b04cc484c7bb2be632f33
 F src/btmutex.c 8acc2f464ee76324bf13310df5692a262b801808984c1b79defb2503bbafadb6
-F src/btree.c 97673c54a3023845e7320cfa9e0de67fd6ca34b37a17a420981bb6e767601310
+F src/btree.c 02376eb7d49ccf31b53c2504f045ad74687c142a5c15ca837516e59e737867dc
 F src/btree.h 32672fa1aa74a7e9ab3aae822f94ffc8e732b1eb005988dc2283f91dc7573398
 F src/btreeInt.h 887cdd2ea7f4a65143074a8a7c8928b0546f8c18dda3c06a408ce7992cbab0c0
 F src/build.c ec6c0bda1e43ef55e5f5121a77ba19fac51fc6585f95ce2da795bcedcf6e8f36
 F src/callback.c d0b853dd413255d2e337b34545e54d888ea02f20da5ad0e63585b389624c4a6c
 F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
-F src/ctime.c 6a77ec9e0eb87aea929e002c816298907e337094a7b556898ae2d1e6be209f90
+F src/ctime.c 6892999ee100bd72b64f84dd7a8f737817d72872648705fbf8ed9575e1f1dd1a
 F src/date.c b29b349d277e3d579dcc295b24c0a2caed83fd8f090a9f7cbe6070c0fd662384
 F src/dbpage.c 8a01e865bf8bc6d7b1844b4314443a6436c07c3efe1d488ed89e81719047833a
 F src/dbstat.c 793deaf88a0904f88285d93d6713c636d55ede0ffd9f08d10f4ea825531d367f
 F src/delete.c 11000121c4281c0bce4e41db29addfaea0038eaa127ece02557c9207bc3e541d
-F src/expr.c b292bdecd64cd695109ceaa3c810f8b41f202368c75adb9ea680a875df5b0308
+F src/expr.c d1e1d42cbdec08bb867a1ab43a59b401d82ff2bc88bdcb4af20e479a5facb6d8
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c 4b575423b0a5d4898b1a7868ce985cf1a8ad91c741c9abbb108ff02536d20f41
 F src/func.c f3dcdc0e95509864767c1f0991b19360f969e44177f4e058fd51da9a6154f47e
@@ -495,9 +496,9 @@ F src/hwtime.h cb1d7e3e1ed94b7aa6fde95ae2c2daccc3df826be26fc9ed7fd90d1750ae6144
 F src/in-operator.md 10cd8f4bcd225a32518407c2fb2484089112fd71
 F src/insert.c 8e4211d04eb460c0694d486c6ba1c068d468c6f653c3f237869a802ad82854de
 F src/legacy.c d7874bc885906868cd51e6c2156698f2754f02d9eee1bae2d687323c3ca8e5aa
-F src/loadext.c 4540fb20e8606b5cea7efee1d727cc69b20390ddc2e6a6c5515e20f96dcc205c
-F src/main.c 652a782cd7b6c6ddf7419fcaf06b8aa9440b7c815857241171c9bdf03ab6544c
-F src/malloc.c cabfef0d725e04c8abfe0231a556ed8b78bf329dcc3fddbf903f6cdcd53cf4e6
+F src/loadext.c 421310045bd78afefb772294a99e50f37d87ae578786a6169074e6291e30d969
+F src/main.c 7e07ff5ec447451d28398d528fda25c272f86cce67bc59a9846ee5bdfb23e1d9
+F src/malloc.c a3e13b001f988ecec6bdb90c0ea8912c8c786e623724d7098da623d8d01d19b1
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c c12a42539b1ba105e3707d0e628ad70e611040d8f5e38cf942cee30c867083de
 F src/mem2.c f1940d9e91948dd6a908fbb9ce3835c36b5d83c3
@@ -519,7 +520,7 @@ F src/os_setup.h 0dbaea40a7d36bf311613d31342e0b99e2536586
 F src/os_unix.c 7ef8b60222558a373d89c18d0c3bc44365b45273a528183d40bec5bb76ce23fc
 F src/os_win.c 035a813cbd17f355bdcad7ab894af214a9c13a1db8aeac902365350b98cd45a7
 F src/os_win.h 7b073010f1451abe501be30d12f6bc599824944a
-F src/pager.c 29ee0618daa1f49c24431a9f21b7ac15fa148eb63626c9e0ac145fffbe0b209d
+F src/pager.c 52cee2f72710be47b5b13ff66b339ca3855e5bc48e92a94114d2affedc70041f
 F src/pager.h 3b33619a90180e0874c7eca31d6f6ceb464d9322c6fb4e9a7bbb318c8a17bdb3
 F src/parse.y c8eff38606f443d5ba245263fa7abc05e4116d95656e050c4b78e9bfbf931add
 F src/pcache.c 385ff064bca69789d199a98e2169445dc16e4291fa807babd61d4890c3b34177
@@ -532,9 +533,9 @@ F src/printf.c 9be6945837c839ba57837b4bc3af349eba630920fa5532aa518816defe42a7d4
 F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384
 F src/resolve.c d36a2b1639e1c33d7b508abfd3452a63e7fd81737f6f3940bfef085fca6f21f4
 F src/rowset.c ba9515a922af32abe1f7d39406b9d35730ed65efab9443dc5702693b60854c92
-F src/select.c ab4eb1aee1bd066feea5b6eff264220ae54459019654264e9f688368a7d0c0b5
-F src/shell.c.in 5402d3a7281576c96d788569778483746859c5e47052facfc4a4ccfac025d5da
-F src/sqlite.h.in fd6fcfe173accab8d9cb9a843856d9e9fb475f893b60a455e01d8739b5076f0e
+F src/select.c c310de94bf67315054587c18a16e7a3e3dc3a98dc79168f0c2b776548d43f6cd
+F src/shell.c.in cf2d24f54412c06e5fb34af7fabc748651125e1dceac29b740e91f06d23447b6
+F src/sqlite.h.in b20d5dc52765ff82f3701395a7e670611ddf138ee0ae84482452ad3a0b5f24b5
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 2d1af80082edffd71c6f96f70ad1ce6a4fb46615ad10291fc77fe0dea9ff0197
 F src/sqliteInt.h 0f3848c46310d197246003f052985b72d1cdbfc0b31e069db76cb5231062fa1d
@@ -605,14 +606,15 @@ F src/utf.c 95fb6e03a5ca679045c5adccd05380f0addccabef5911abddcb06af069500ab7
 F src/util.c 3b6cedf7a0c69bd6e1acce832873952d416212d6293b18d03064e07d7a9b5118
 F src/vacuum.c f25d3b39681595e321a8a4e7fca3e5971cb14a401213d0742c9bf7d4ce8c2a1a
 F src/vdbe.c 972999395eee88702091fb5d50cf4effd07889c371807d222a7f517388e6378e
-F src/vdbe.h 51282fbe819ee0e8eeeaab176240860d334c20a12b14f3b363e7f1a4e05d60b9
-F src/vdbeInt.h 0b728ee662862a38b1912af741e2ac64f524de3c77aa86cf4306c42bdcd9de59
+F src/vdbe.h 07b8c636a87df8b6e58f29d6badd7f10d5844353deff1d7c88ed1c2bfe3bbd35
+F src/vdbeInt.h 571413068b5ac07e2ed8ca7a02fa529622fd5455ae6981498376e5e492d2e5ef
 F src/vdbeapi.c d176ee7251d5344de7bb2a0d2dd0fe536834e5843d9bc2389e0f5cdcd5374141
-F src/vdbeaux.c 8349559e72bf0cfa2258b1159b004ec4d1717a054d2e1829c8cc897c32da8752
+F src/vdbeaux.c 319a6e44cff0e8ba710a8374778043609d11cf82cb4ab2ba0a80dde52e607a08
 F src/vdbeblob.c 253ed82894924c362a7fa3079551d3554cd1cdace39aa833da77d3bc67e7c1b1
 F src/vdbemem.c 39b942ecca179f4f30a32b54579a85d74ccaefa5af2a0ad2700abe5ef0768b22
 F src/vdbesort.c 2be76d26998ce2b3324cdcc9f6443728e54b6c7677c553ad909c7d7cfab587df
 F src/vdbetrace.c fa3bf238002f0bbbdfb66cc8afb0cea284ff9f148d6439bc1f6f2b4c3b7143f0
+F src/vdbevtab.c 8094dfc28dad82d60a1c832020a1b201a5381dc185c14638affc6d4e9d54c653
 F src/vtab.c 7b704a90515a239c6cdba6a66b1bb3a385e62326cceb5ecb05ec7a091d6b8515
 F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
 F src/wal.c ea8dad28bb0e2b85ac1ab7618968687ff5fd522af8a1a38d6960ec176ebc8ee6
@@ -821,7 +823,7 @@ F test/descidx1.test edc8adee58d491b06c7157c50364eaf1c3605c9c19f8093cb1ea2b6184f
 F test/descidx2.test a0ba347037ff3b811f4c6ceca5fd0f9d5d72e74e59f2d9de346a9d2f6ad78298
 F test/descidx3.test 953c831df7ea219c73826dfbf2f6ee02d95040725aa88ccb4fa43d1a1999b926
 F test/diskfull.test 106391384780753ea6896b7b4f005d10e9866b6e
-F test/distinct.test 8b6c652f0b2d477f0830884736f2a1cd2e8f7fc10a04aa6d571a401fa13ed88b
+F test/distinct.test e7d0cf371944dd0cbedff86420744e2f1ea2b528156451c97eb6ff41a99b9236
 F test/distinct2.test 11b0594c932098e969d084ba45ab81d5040f4d4e766db65d49146705a305ed98
 F test/distinctagg.test 1a6ef9c87a58669438fc771450d7a72577417376
 F test/e_blobbytes.test 439a945953b35cb6948a552edaec4dc31fd70a05
@@ -967,7 +969,7 @@ F test/fts3fuzz001.test e3c7b0ce9b04cc02281dcc96812a277f02df03cd7dc082055d87e11e
 F test/fts3join.test 949b4f5ae3ae9cc2423cb865d711e32476bdb205ab2be923fdf48246e4a44166
 F test/fts3malloc.test b0e4c133b8d61d4f6d112d8110f8320e9e453ef6
 F test/fts3matchinfo.test aa66cc50615578b30f6df9984819ae5b702511cf8a94251ec7c594096a703a4a
-F test/fts3misc.test 236f37a57d97fa1b7e0a4303aab7e02da87a9818c106e513ae88af76f25ace4a
+F test/fts3misc.test 9ec15e7c0b5831a6353bd4c46bf3acdf1360eda5d9f396f667db4d05bcf92ecf
 F test/fts3near.test 7e3354d46f155a822b59c0e957fd2a70c1d7e905
 F test/fts3offsets.test b85fd382abdc78ebce721d8117bd552dfb75094c
 F test/fts3prefix.test fa794eaab0bdae466494947b0b153d7844478ab2
@@ -1093,7 +1095,7 @@ F test/ioerr5.test 2edfa4fb0f896f733071303b42224df8bedd9da4
 F test/ioerr6.test a395a6ab144b26a9e3e21059a1ab6a7149cca65b
 F test/istrue.test 75327829744e65cc8700e69340b8e6c192e10e39dfae7ccb0e970d3c4f49090a
 F test/join.test bca044589e94bb466e4c1e91fb6fecdc3f3326ca6b3f590f555f1958156eb321
-F test/join2.test 659bc6193f5c3fe20fa444dd2c91713db8c33e376b098b860644e175e87b8dbc
+F test/join2.test 7d24d095ab88d3910228d53a3b548b7baf2e0e7d8aac6731a273e300e1b34b61
 F test/join3.test 6f0c774ff1ba0489e6c88a3e77b9d3528fb4fda0
 F test/join4.test 1a352e4e267114444c29266ce79e941af5885916
 F test/join5.test 3a96dc62f0b45402d7207e22d1993fe0c2fce1c57644a11439891dd62b990eb7
@@ -1713,7 +1715,7 @@ F test/whereH.test e4b07f7a3c2f5d31195cd33710054c78667573b2
 F test/whereI.test a2874062140ed4aba9ffae76e6190a3df6fc73d1373fdfa8fd632945082a5364
 F test/whereJ.test 88287550f6ee604422403b053455b1ad894eeaa5c35d348532dfa1439286cb9a
 F test/whereK.test f8e3cf26a8513ecc7f514f54df9f0572c046c42b
-F test/whereL.test d19499a39c9e3e5a74460778b009558d328c8a230c0e6825c9996c9adff89058
+F test/whereL.test e05cedc9389c6f09ad55bd5999a3fddccebec90672fb989433c145dcdaf26996
 F test/wherefault.test 1374c3aa198388925246475f84ad4cd5f9528864
 F test/wherelfault.test 9012e4ef5259058b771606616bd007af5d154e64cc25fa9fd4170f6411db44e3
 F test/wherelimit.test 592081800806d297dd7449b1030c863d2883d6d42901837ccd2e5a9bd962edb0
@@ -1799,7 +1801,7 @@ F tool/mkshellc.tcl 70a9978e363b0f3280ca9ce1c46d72563ff479c1930a12a7375e3881b732
 F tool/mksourceid.c 36aa8020014aed0836fd13c51d6dc9219b0df1761d6b5f58ff5b616211b079b9
 F tool/mkspeedsql.tcl a1a334d288f7adfe6e996f2e712becf076745c97
 F tool/mksqlite3c-noext.tcl 4f7cfef5152b0c91920355cbfc1d608a4ad242cb819f1aea07f6d0274f584a7f
-F tool/mksqlite3c.tcl 5fed3d75069d8f66f202d3b5200b0cea4aa7108481acd06732a06fdd42eb83a2
+F tool/mksqlite3c.tcl 3ab95bcf7b765f9d6d99cbeb8c4f150b38b0bb1f001ffac688f2ad02ebce2123
 F tool/mksqlite3h.tcl 080873e3856eceb9d289a08a00c4b30f875ea3feadcbece796bd509b1532792c
 F tool/mksqlite3internalh.tcl eb994013e833359137eb53a55acdad0b5ae1049b
 F tool/mkvsix.tcl b9e0777a213c23156b6542842c238479e496ebf5
@@ -1818,7 +1820,7 @@ F tool/showshm.c a0ab6ec32dd1f11218ca2a4018f8fb875b59414801ab8ceed8b2e69b7b45a80
 F tool/showstat4.c 0682ebea7abf4d3657f53c4a243f2e7eab48eab344ed36a94bb75dcd19a5c2a1
 F tool/showwal.c ad9d768f96ca6199ad3a8c9562d679680bd032dd01204ea3e5ea6fb931d81847
 F tool/soak1.tcl 8d407956e1a45b485a8e072470a3e629a27037fe
-F tool/spaceanal.tcl 4bfd19aad7eb3ce0372ef0255f58035e0bba4ff5e9acfd763a10c6fb365c8dec
+F tool/spaceanal.tcl c161d838825d0242317c7cc13b1eb2126f8cec031950ef31114d42732cb2674e
 F tool/speed-check.sh 2b042d703a9472f08c3b13be27afac658426f8e4fc87cd2d575953fda86f08d1
 F tool/speedtest.tcl 06c76698485ccf597b9e7dbb1ac70706eb873355
 F tool/speedtest16.c ecb6542862151c3e6509bbc00509b234562ae81e
@@ -1861,7 +1863,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P ae697b152d22737169892411a0c4d908895ff5fb249cce9bdb1ba0bbe32806f0
-R cc7f5aa23076777d96573db8bef15752
+P 96dfc71ea599702ef38b60952d03e95dce5a8c534cd943e076e9c76b00e61e65
+R 8a6312f86dfd0f2dc1b9dbd32625eb27
 U drh
-Z 0fbe741b842883ec4b35af5da437ce6d
+Z 054131aab304a488c76322b7f6a162fc

manifest.uuid

@@ -1 +1 @@
-3cabe06b6e9433cbfb4bf7bd72a425f43b54f57d84a205adbaa6a1147bbe46bf
+baa720e4a88f268ed95337daab5f434fd3263b00f09101cddc6424765bf3b722

src/btree.c

@@ -2913,6 +2913,10 @@ int sqlite3BtreeGetReserveNoMutex(Btree *p){
 ** Return the number of bytes of space at the end of every page that
 ** are intentually left unused.  This is the "reserved" space that is
 ** sometimes used by extensions.
+**
+** The value returned is the larger of the current reserve size and
+** the latest reserve size requested by SQLITE_FILECTRL_RESERVE_BYTES.
+** The amount of reserve can only grow - never shrink.
 */
 int sqlite3BtreeGetRequestedReserve(Btree *p){
   int n;

src/ctime.c

@@ -193,6 +193,9 @@ static const char * const sqlite3azCompileOpt[] = {
 #if SQLITE_ENABLE_BATCH_ATOMIC_WRITE
   "ENABLE_BATCH_ATOMIC_WRITE",
 #endif
+#if SQLITE_ENABLE_BYTECODE_VTAB
+  "ENABLE_BYTECODE_VTAB",
+#endif
 #if SQLITE_ENABLE_CEROD
   "ENABLE_CEROD=" CTIMEOPT_VAL(SQLITE_ENABLE_CEROD),
 #endif

src/expr.c

@@ -45,7 +45,7 @@ char sqlite3TableColumnAffinity(Table *pTab, int iCol){
 char sqlite3ExprAffinity(const Expr *pExpr){
   int op;
   while( ExprHasProperty(pExpr, EP_Skip) ){
-    assert( pExpr->op==TK_COLLATE );
+    assert( pExpr->op==TK_COLLATE || pExpr->op==TK_IF_NULL_ROW );
     pExpr = pExpr->pLeft;
     assert( pExpr!=0 );
   }
@@ -112,7 +112,7 @@ Expr *sqlite3ExprAddCollateString(Parse *pParse, Expr *pExpr, const char *zC){
 */
 Expr *sqlite3ExprSkipCollate(Expr *pExpr){
   while( pExpr && ExprHasProperty(pExpr, EP_Skip) ){
-    assert( pExpr->op==TK_COLLATE );
+    assert( pExpr->op==TK_COLLATE || pExpr->op==TK_IF_NULL_ROW );
     pExpr = pExpr->pLeft;
   }   
   return pExpr;
@@ -131,7 +131,7 @@ Expr *sqlite3ExprSkipCollateAndLikely(Expr *pExpr){
       assert( pExpr->op==TK_FUNCTION );
       pExpr = pExpr->x.pList->a[0].pExpr;
     }else{
-      assert( pExpr->op==TK_COLLATE );
+      assert( pExpr->op==TK_COLLATE || pExpr->op==TK_IF_NULL_ROW );
       pExpr = pExpr->pLeft;
     }
   }   

src/loadext.c

@@ -480,6 +480,14 @@ static const sqlite3_api_routines sqlite3Apis = {
   sqlite3_database_file_object,
 };
 
+/* True if x is the directory separator character
+*/
+#if SQLITE_OS_WIN
+# define DirSep(X)  ((X)=='/'||(X)=='\\')
+#else
+# define DirSep(X)  ((X)=='/')
+#endif
+
 /*
 ** Attempt to load an SQLite extension library contained in the file
 ** zFile.  The entry point is zProc.  zProc may be 0 in which case a
@@ -581,7 +589,7 @@ static int sqlite3LoadExtension(
       return SQLITE_NOMEM_BKPT;
     }
     memcpy(zAltEntry, "sqlite3_", 8);
-    for(iFile=ncFile-1; iFile>=0 && zFile[iFile]!='/'; iFile--){}
+    for(iFile=ncFile-1; iFile>=0 && !DirSep(zFile[iFile]); iFile--){}
     iFile++;
     if( sqlite3_strnicmp(zFile+iFile, "lib", 3)==0 ) iFile += 3;
     for(iEntry=8; (c = zFile[iFile])!=0 && c!='.'; iFile++){

src/main.c

@@ -3358,6 +3358,12 @@ static int openDatabase(
   }
 #endif
 
+#ifdef SQLITE_ENABLE_BYTECODE_VTAB
+  if( !db->mallocFailed && rc==SQLITE_OK){
+    rc = sqlite3VdbeBytecodeVtabInit(db);
+  }
+#endif
+
 #ifdef SQLITE_ENABLE_INTERNAL_FUNCTIONS
   /* Testing use only!!! The -DSQLITE_ENABLE_INTERNAL_FUNCTIONS=1 compile-time
   ** option gives access to internal functions by default.  

src/malloc.c

@@ -111,7 +111,7 @@ sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 n){
   }
   mem0.alarmThreshold = n;
   nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
-  mem0.nearlyFull = (n>0 && n<=nUsed);
+  AtomicStore(&mem0.nearlyFull, n>0 && n<=nUsed);
   sqlite3_mutex_leave(mem0.mutex);
   excess = sqlite3_memory_used() - n;
   if( excess>0 ) sqlite3_release_memory((int)(excess & 0x7fffffff));
@@ -179,7 +179,7 @@ int sqlite3MallocInit(void){
 ** sqlite3_soft_heap_limit().
 */
 int sqlite3HeapNearlyFull(void){
-  return mem0.nearlyFull;
+  return AtomicLoad(&mem0.nearlyFull);
 }
 
 /*
@@ -243,7 +243,7 @@ static void mallocWithAlarm(int n, void **pp){
   if( mem0.alarmThreshold>0 ){
     sqlite3_int64 nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
     if( nUsed >= mem0.alarmThreshold - nFull ){
-      mem0.nearlyFull = 1;
+      AtomicStore(&mem0.nearlyFull, 1);
       sqlite3MallocAlarm(nFull);
       if( mem0.hardLimit ){
         nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
@@ -253,7 +253,7 @@ static void mallocWithAlarm(int n, void **pp){
         }
       }
     }else{
-      mem0.nearlyFull = 0;
+      AtomicStore(&mem0.nearlyFull, 0);
     }
   }
   p = sqlite3GlobalConfig.m.xMalloc(nFull);

src/pager.c

@@ -2536,9 +2536,12 @@ static int pager_delmaster(Pager *pPager, const char *zMaster){
       /* One of the journals pointed to by the master journal exists.
       ** Open it and check if it points at the master journal. If
       ** so, return without deleting the master journal file.
+      ** NB:  zJournal is really a MAIN_JOURNAL.  But call it a 
+      ** MASTER_JOURNAL here so that the VFS will not send the zJournal
+      ** name into sqlite3_database_file_object().
       */
       int c;
-      int flags = (SQLITE_OPEN_READONLY|SQLITE_OPEN_MAIN_JOURNAL);
+      int flags = (SQLITE_OPEN_READONLY|SQLITE_OPEN_MASTER_JOURNAL);
       rc = sqlite3OsOpen(pVfs, zJournal, pJournal, flags, 0);
       if( rc!=SQLITE_OK ){
         goto delmaster_out;

src/select.c

@@ -3498,6 +3498,7 @@ static Expr *substExpr(
           ifNullRow.op = TK_IF_NULL_ROW;
           ifNullRow.pLeft = pCopy;
           ifNullRow.iTable = pSubst->iNewTable;
+          ifNullRow.flags = EP_Skip;
           pCopy = &ifNullRow;
         }
         testcase( ExprHasProperty(pCopy, EP_Subquery) );

src/shell.c.in

@@ -3158,6 +3158,7 @@ static int shell_exec(
             const char *zEQPLine = (const char*)sqlite3_column_text(pExplain,3);
             int iEqpId = sqlite3_column_int(pExplain, 0);
             int iParentId = sqlite3_column_int(pExplain, 1);
+            if( zEQPLine==0 ) zEQPLine = "";
             if( zEQPLine[0]=='-' ) eqp_render(pArg);
             eqp_append(pArg, iEqpId, iParentId, zEQPLine);
           }
@@ -5067,12 +5068,7 @@ static int shell_dbinfo_command(ShellState *p, int nArg, char **azArg){
              "SELECT data FROM sqlite_dbpage(?1) WHERE pgno=1",
              -1, &pStmt, 0);
   if( rc ){
-    if( !sqlite3_compileoption_used("ENABLE_DBPAGE_VTAB") ){
-      utf8_printf(stderr, "the \".dbinfo\" command requires the "
-                          "-DSQLITE_ENABLE_DBPAGE_VTAB compile-time options\n");
-    }else{
-      utf8_printf(stderr, "error: %s\n", sqlite3_errmsg(p->db));
-    }
+    utf8_printf(stderr, "error: %s\n", sqlite3_errmsg(p->db));
     sqlite3_finalize(pStmt);
     return 1;
   }
@@ -8346,7 +8342,7 @@ static int do_meta_command(char *zLine, ShellState *p){
     int i;
     int eMode = 0;
     int bBOM = 0;
-    int bOnce;
+    int bOnce = 0;  /* 0: .output, 1: .once, 2: .excel */
 
     if( c=='e' ){
       eMode = 'x';

src/sqlite.h.in

@@ -299,26 +299,22 @@ typedef sqlite_uint64 sqlite3_uint64;
 ** the [sqlite3] object is successfully destroyed and all associated
 ** resources are deallocated.
 **
-** ^If the database connection is associated with unfinalized prepared
-** statements or unfinished sqlite3_backup objects then sqlite3_close()
-** will leave the database connection open and return [SQLITE_BUSY].
-** ^If sqlite3_close_v2() is called with unfinalized prepared statements
-** and/or unfinished sqlite3_backups, then the database connection becomes
-** an unusable "zombie" which will automatically be deallocated when the
-** last prepared statement is finalized or the last sqlite3_backup is
-** finished.  The sqlite3_close_v2() interface is intended for use with
-** host languages that are garbage collected, and where the order in which
-** destructors are called is arbitrary.
-**
-** Applications should [sqlite3_finalize | finalize] all [prepared statements],
-** [sqlite3_blob_close | close] all [BLOB handles], and 
+** Ideally, applications should [sqlite3_finalize | finalize] all
+** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and 
 ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
-** with the [sqlite3] object prior to attempting to close the object.  ^If
-** sqlite3_close_v2() is called on a [database connection] that still has
-** outstanding [prepared statements], [BLOB handles], and/or
-** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation
-** of resources is deferred until all [prepared statements], [BLOB handles],
-** and [sqlite3_backup] objects are also destroyed.
+** with the [sqlite3] object prior to attempting to close the object.
+** ^If the database connection is associated with unfinalized prepared
+** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then
+** sqlite3_close() will leave the database connection open and return
+** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared
+** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups,
+** it returns [SQLITE_OK] regardless, but instead of deallocating the database
+** connection immediately, it marks the database connection as an unusable
+** "zombie" and makes arrangements to automatically deallocate the database
+** connection after all prepared statements are finalized, all BLOB handles
+** are closed, and all backups have finished. The sqlite3_close_v2() interface
+** is intended for use with host languages that are garbage collected, and
+** where the order in which destructors are called is arbitrary.
 **
 ** ^If an [sqlite3] object is destroyed while a transaction is open,
 ** the transaction is automatically rolled back.
@@ -507,6 +503,7 @@ int sqlite3_exec(
 #define SQLITE_IOERR_BEGIN_ATOMIC      (SQLITE_IOERR | (29<<8))
 #define SQLITE_IOERR_COMMIT_ATOMIC     (SQLITE_IOERR | (30<<8))
 #define SQLITE_IOERR_ROLLBACK_ATOMIC   (SQLITE_IOERR | (31<<8))
+#define SQLITE_IOERR_DATA              (SQLITE_IOERR | (32<<8))
 #define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
 #define SQLITE_LOCKED_VTAB             (SQLITE_LOCKED |  (2<<8))
 #define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
@@ -3536,8 +3533,19 @@ int sqlite3_open_v2(
 ** that check if a database file was a URI that contained a specific query 
 ** parameter, and if so obtains the value of that query parameter.
 **
-** If F is the database filename pointer passed into the xOpen() method of 
-** a VFS implementation or it is the return value of [sqlite3_db_filename()]
+** The first parameter to these interfaces (hereafter referred to
+** as F) must be one of:
+** <ul>
+** <li> A database filename pointer created by the SQLite core and
+** passed into the xOpen() method of a VFS implemention, or
+** <li> A filename obtained from [sqlite3_db_filename()], or
+** <li> A new filename constructed using [sqlite3_create_filename()].
+** </ul>
+** If the F parameter is not one of the above, then the behavior is
+** undefined and probably undesirable.  Older versions of SQLite were
+** more tolerant of invalid F parameters than newer versions.
+**
+** If F is a suitable filename (as described in the previous paragraph)
 ** and if P is the name of the query parameter, then
 ** sqlite3_uri_parameter(F,P) returns the value of the P
 ** parameter if it exists or a NULL pointer if P does not appear as a 
@@ -3673,7 +3681,7 @@ sqlite3_file *sqlite3_database_file_object(const char*);
 **
 ** The sqlite3_free_filename(Y) routine releases a memory allocation
 ** previously obtained from sqlite3_create_filename().  Invoking
-** sqlite3_free_filename(Y) is a NULL pointer is a harmless no-op.
+** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op.
 **
 ** If the Y parameter to sqlite3_free_filename(Y) is anything other
 ** than a NULL pointer or a pointer previously acquired from

src/vdbe.h

@@ -290,6 +290,9 @@ void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
 int sqlite3VdbeHasSubProgram(Vdbe*);
 
 int sqlite3NotPureFunc(sqlite3_context*);
+#ifdef SQLITE_ENABLE_BYTECODE_VTAB
+int sqlite3VdbeBytecodeVtabInit(sqlite3*);
+#endif
 
 /* Use SQLITE_ENABLE_COMMENTS to enable generation of extra comments on
 ** each VDBE opcode.

src/vdbeInt.h

@@ -31,7 +31,8 @@
 ** "explain" P4 display logic is enabled.
 */
 #if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) \
-     || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
+     || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG) \
+     || defined(SQLITE_ENABLE_BYTECODE_VTAB)
 # define VDBE_DISPLAY_P4 1
 #else
 # define VDBE_DISPLAY_P4 0
@@ -496,7 +497,14 @@ int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
 int sqlite3VdbeIdxKeyCompare(sqlite3*,VdbeCursor*,UnpackedRecord*,int*);
 int sqlite3VdbeIdxRowid(sqlite3*, BtCursor*, i64*);
 int sqlite3VdbeExec(Vdbe*);
-#ifndef SQLITE_OMIT_EXPLAIN
+#if !defined(SQLITE_OMIT_EXPLAIN) || defined(SQLITE_ENABLE_BYTECODE_VTAB)
+int sqlite3VdbeNextOpcode(Vdbe*,Mem*,int,int*,int*,Op**);
+char *sqlite3VdbeDisplayP4(sqlite3*,Op*);
+#endif
+#if defined(SQLITE_ENABLE_EXPLAIN_COMMENTS)
+char *sqlite3VdbeDisplayComment(sqlite3*,const Op*,const char*);
+#endif
+#if !defined(SQLITE_OMIT_EXPLAIN)
 int sqlite3VdbeList(Vdbe*);
 #endif
 int sqlite3VdbeHalt(Vdbe*);
@@ -538,7 +546,7 @@ int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
 #ifndef SQLITE_OMIT_WINDOWFUNC
 int sqlite3VdbeMemAggValue(Mem*, Mem*, FuncDef*);
 #endif
-#ifndef SQLITE_OMIT_EXPLAIN
+#if !defined(SQLITE_OMIT_EXPLAIN) || defined(SQLITE_ENABLE_BYTECODE_VTAB)
 const char *sqlite3OpcodeName(int);
 #endif
 int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);

src/vdbeaux.c

@@ -1464,11 +1464,10 @@ static int translateP(char c, const Op *pOp){
 **       "PX@PY+1" ->  "r[X..X+Y]"    or "r[x]" if y is 0
 **       "PY..PY"  ->  "r[X..Y]"      or "r[x]" if y<=x
 */
-static int displayComment(
+char *sqlite3VdbeDisplayComment(
+  sqlite3 *db,       /* Optional - Oom error reporting only */
   const Op *pOp,     /* The opcode to be commented */
-  const char *zP4,   /* Previously obtained value for P4 */
-  char *zTemp,       /* Write result here */
-  int nTemp          /* Space available in zTemp[] */
+  const char *zP4    /* Previously obtained value for P4 */
 ){
   const char *zOpName;
   const char *zSynopsis;
@@ -1476,8 +1475,8 @@ static int displayComment(
   int ii;
   char zAlt[50];
   StrAccum x;
-  sqlite3StrAccumInit(&x, 0, zTemp, nTemp, 0);
 
+  sqlite3StrAccumInit(&x, 0, 0, 0, SQLITE_MAX_LENGTH);
   zOpName = sqlite3OpcodeName(pOp->opcode);
   nOpName = sqlite3Strlen30(zOpName);
   if( zOpName[nOpName+1] ){
@@ -1544,10 +1543,12 @@ static int displayComment(
   }else if( pOp->zComment ){
     sqlite3_str_appendall(&x, pOp->zComment);
   }
-  sqlite3StrAccumFinish(&x);
-  return x.nChar;
+  if( (x.accError & SQLITE_NOMEM)!=0 && db!=0 ){
+    sqlite3OomFault(db);
+  }
+  return sqlite3StrAccumFinish(&x);
 }
-#endif /* SQLITE_DEBUG */
+#endif /* SQLITE_ENABLE_EXPLAIN_COMMENTS */
 
 #if VDBE_DISPLAY_P4 && defined(SQLITE_ENABLE_CURSOR_HINTS)
 /*
@@ -1628,11 +1629,11 @@ static void displayP4Expr(StrAccum *p, Expr *pExpr){
 ** Compute a string that describes the P4 parameter for an opcode.
 ** Use zTemp for any required temporary buffer space.
 */
-static char *displayP4(Op *pOp, char *zTemp, int nTemp){
-  char *zP4 = zTemp;
+char *sqlite3VdbeDisplayP4(sqlite3 *db, Op *pOp){
+  char *zP4 = 0;
   StrAccum x;
-  assert( nTemp>=20 );
-  sqlite3StrAccumInit(&x, 0, zTemp, nTemp, 0);
+
+  sqlite3StrAccumInit(&x, 0, 0, 0, SQLITE_MAX_LENGTH);
   switch( pOp->p4type ){
     case P4_KEYINFO: {
       int j;
@@ -1716,36 +1717,32 @@ static char *displayP4(Op *pOp, char *zTemp, int nTemp){
       int n = ai[0];   /* The first element of an INTARRAY is always the
                        ** count of the number of elements to follow */
       for(i=1; i<=n; i++){
-        sqlite3_str_appendf(&x, ",%d", ai[i]);
+        sqlite3_str_appendf(&x, "%c%d", (i==1 ? '[' : ','), ai[i]);
       }
-      zTemp[0] = '[';
       sqlite3_str_append(&x, "]", 1);
       break;
     }
     case P4_SUBPROGRAM: {
-      sqlite3_str_appendf(&x, "program");
+      zP4 = "program";
       break;
     }
     case P4_DYNBLOB:
     case P4_ADVANCE: {
-      zTemp[0] = 0;
       break;
     }
     case P4_TABLE: {
-      sqlite3_str_appendf(&x, "%s", pOp->p4.pTab->zName);
+      zP4 = pOp->p4.pTab->zName;
       break;
     }
     default: {
       zP4 = pOp->p4.z;
-      if( zP4==0 ){
-        zP4 = zTemp;
-        zTemp[0] = 0;
-      }
     }
   }
-  sqlite3StrAccumFinish(&x);
-  assert( zP4!=0 );
-  return zP4;
+  if( zP4 ) sqlite3_str_appendall(&x, zP4);
+  if( (x.accError & SQLITE_NOMEM)!=0 ){
+    sqlite3OomFault(db);
+  }
+  return sqlite3StrAccumFinish(&x);
 }
 #endif /* VDBE_DISPLAY_P4 */
 
@@ -1835,24 +1832,28 @@ void sqlite3VdbeLeave(Vdbe *p){
 */
 void sqlite3VdbePrintOp(FILE *pOut, int pc, VdbeOp *pOp){
   char *zP4;
-  char zPtr[50];
-  char zCom[100];
+  char *zCom;
+  sqlite3 dummyDb;
   static const char *zFormat1 = "%4d %-13s %4d %4d %4d %-13s %.2X %s\n";
   if( pOut==0 ) pOut = stdout;
-  zP4 = displayP4(pOp, zPtr, sizeof(zPtr));
+  dummyDb.mallocFailed = 1;
+  zP4 = sqlite3VdbeDisplayP4(&dummyDb, pOp);
 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
-  displayComment(pOp, zP4, zCom, sizeof(zCom));
+  zCom = sqlite3VdbeDisplayComment(0, pOp, zP4);
 #else
-  zCom[0] = 0;
+  zCom = 0;
 #endif
   /* NB:  The sqlite3OpcodeName() function is implemented by code created
   ** by the mkopcodeh.awk and mkopcodec.awk scripts which extract the
   ** information from the vdbe.c source text */
   fprintf(pOut, zFormat1, pc, 
-      sqlite3OpcodeName(pOp->opcode), pOp->p1, pOp->p2, pOp->p3, zP4, pOp->p5,
-      zCom
+      sqlite3OpcodeName(pOp->opcode), pOp->p1, pOp->p2, pOp->p3, 
+      zP4 ? zP4 : "", pOp->p5,
+      zCom ? zCom : ""
   );
   fflush(pOut);
+  sqlite3_free(zP4);
+  sqlite3_free(zCom);
 }
 #endif
 
@@ -1943,6 +1944,121 @@ void sqlite3VdbeFrameMemDel(void *pArg){
   pFrame->v->pDelFrame = pFrame;
 }
 
+#if defined(SQLITE_ENABLE_BYTECODE_VTAB) || !defined(SQLITE_OMIT_EXPLAIN)
+/*
+** Locate the next opcode to be displayed in EXPLAIN or EXPLAIN
+** QUERY PLAN output.
+**
+** Return SQLITE_ROW on success.  Return SQLITE_DONE if there are no
+** more opcodes to be displayed.
+*/
+int sqlite3VdbeNextOpcode(
+  Vdbe *p,         /* The statement being explained */
+  Mem *pSub,       /* Storage for keeping track of subprogram nesting */
+  int eMode,       /* 0: normal.  1: EQP.  2:  TablesUsed */
+  int *piPc,       /* IN/OUT: Current rowid.  Overwritten with next rowid */
+  int *piAddr,     /* OUT: Write index into (*paOp)[] here */
+  Op **paOp        /* OUT: Write the opcode array here */
+){
+  int nRow;                            /* Stop when row count reaches this */
+  int nSub = 0;                        /* Number of sub-vdbes seen so far */
+  SubProgram **apSub = 0;              /* Array of sub-vdbes */
+  int i;                               /* Next instruction address */
+  int rc = SQLITE_OK;                  /* Result code */
+  Op *aOp = 0;                         /* Opcode array */
+  int iPc;                             /* Rowid.  Copy of value in *piPc */
+
+  /* When the number of output rows reaches nRow, that means the
+  ** listing has finished and sqlite3_step() should return SQLITE_DONE.
+  ** nRow is the sum of the number of rows in the main program, plus
+  ** the sum of the number of rows in all trigger subprograms encountered
+  ** so far.  The nRow value will increase as new trigger subprograms are
+  ** encountered, but p->pc will eventually catch up to nRow.
+  */
+  nRow = p->nOp;
+  if( pSub!=0 ){
+    if( pSub->flags&MEM_Blob ){
+      /* pSub is initiallly NULL.  It is initialized to a BLOB by
+      ** the P4_SUBPROGRAM processing logic below */
+      nSub = pSub->n/sizeof(Vdbe*);
+      apSub = (SubProgram **)pSub->z;
+    }
+    for(i=0; i<nSub; i++){
+      nRow += apSub[i]->nOp;
+    }
+  }
+  iPc = *piPc;
+  while(1){  /* Loop exits via break */
+    i = iPc++;
+    if( i>=nRow ){
+      p->rc = SQLITE_OK;
+      rc = SQLITE_DONE;
+      break;
+    }
+    if( i<p->nOp ){
+      /* The rowid is small enough that we are still in the
+      ** main program. */
+      aOp = p->aOp;
+    }else{
+      /* We are currently listing subprograms.  Figure out which one and
+      ** pick up the appropriate opcode. */
+      int j;
+      i -= p->nOp;
+      assert( apSub!=0 );
+      assert( nSub>0 );
+      for(j=0; i>=apSub[j]->nOp; j++){
+        i -= apSub[j]->nOp;
+        assert( i<apSub[j]->nOp || j+1<nSub );
+      }
+      aOp = apSub[j]->aOp;
+    }
+
+    /* When an OP_Program opcode is encounter (the only opcode that has
+    ** a P4_SUBPROGRAM argument), expand the size of the array of subprograms
+    ** kept in p->aMem[9].z to hold the new program - assuming this subprogram
+    ** has not already been seen.
+    */
+    if( pSub!=0 && aOp[i].p4type==P4_SUBPROGRAM ){
+      int nByte = (nSub+1)*sizeof(SubProgram*);
+      int j;
+      for(j=0; j<nSub; j++){
+        if( apSub[j]==aOp[i].p4.pProgram ) break;
+      }
+      if( j==nSub ){
+        p->rc = sqlite3VdbeMemGrow(pSub, nByte, nSub!=0);
+        if( p->rc!=SQLITE_OK ){
+          rc = SQLITE_ERROR;
+          break;
+        }
+        apSub = (SubProgram **)pSub->z;
+        apSub[nSub++] = aOp[i].p4.pProgram;
+        MemSetTypeFlag(pSub, MEM_Blob);
+        pSub->n = nSub*sizeof(SubProgram*);
+        nRow += aOp[i].p4.pProgram->nOp;
+      }
+    }
+    if( eMode==0 ) break;
+#ifdef SQLITE_ENABLE_BYTECODE_VTAB
+    if( eMode==2 ){
+      Op *pOp = aOp + i;
+      if( pOp->opcode==OP_OpenRead ) break;
+      if( pOp->opcode==OP_OpenWrite && (pOp->p5 & OPFLAG_P2ISREG)==0 ) break;
+      if( pOp->opcode==OP_ReopenIdx ) break;      
+    }else
+#endif
+    {
+      assert( eMode==1 );
+      if( aOp[i].opcode==OP_Explain ) break;
+      if( aOp[i].opcode==OP_Init && iPc>1 ) break;
+    }
+  }
+  *piPc = iPc;
+  *piAddr = i;
+  *paOp = aOp;
+  return rc;
+}
+#endif /* SQLITE_ENABLE_BYTECODE_VTAB || !SQLITE_OMIT_EXPLAIN */
+
 
 /*
 ** Delete a VdbeFrame object and its contents. VdbeFrame objects are
@@ -1983,16 +2099,14 @@ void sqlite3VdbeFrameDelete(VdbeFrame *p){
 int sqlite3VdbeList(
   Vdbe *p                   /* The VDBE */
 ){
-  int nRow;                            /* Stop when row count reaches this */
-  int nSub = 0;                        /* Number of sub-vdbes seen so far */
-  SubProgram **apSub = 0;              /* Array of sub-vdbes */
   Mem *pSub = 0;                       /* Memory cell hold array of subprogs */
   sqlite3 *db = p->db;                 /* The database connection */
   int i;                               /* Loop counter */
   int rc = SQLITE_OK;                  /* Return code */
   Mem *pMem = &p->aMem[1];             /* First Mem of result set */
   int bListSubprogs = (p->explain==1 || (db->flags & SQLITE_TriggerEQP)!=0);
-  Op *pOp = 0;
+  Op *aOp;                             /* Array of opcodes */
+  Op *pOp;                             /* Current opcode */
 
   assert( p->explain );
   assert( p->magic==VDBE_MAGIC_RUN );
@@ -2012,14 +2126,6 @@ int sqlite3VdbeList(
     return SQLITE_ERROR;
   }
 
-  /* When the number of output rows reaches nRow, that means the
-  ** listing has finished and sqlite3_step() should return SQLITE_DONE.
-  ** nRow is the sum of the number of rows in the main program, plus
-  ** the sum of the number of rows in all trigger subprograms encountered
-  ** so far.  The nRow value will increase as new trigger subprograms are
-  ** encountered, but p->pc will eventually catch up to nRow.
-  */
-  nRow = p->nOp;
   if( bListSubprogs ){
     /* The first 8 memory cells are used for the result set.  So we will
     ** commandeer the 9th cell to use as storage for an array of pointers
@@ -2027,147 +2133,55 @@ int sqlite3VdbeList(
     ** cells.  */
     assert( p->nMem>9 );
     pSub = &p->aMem[9];
-    if( pSub->flags&MEM_Blob ){
-      /* On the first call to sqlite3_step(), pSub will hold a NULL.  It is
-      ** initialized to a BLOB by the P4_SUBPROGRAM processing logic below */
-      nSub = pSub->n/sizeof(Vdbe*);
-      apSub = (SubProgram **)pSub->z;
-    }
-    for(i=0; i<nSub; i++){
-      nRow += apSub[i]->nOp;
-    }
+  }else{
+    pSub = 0;
   }
 
-  while(1){  /* Loop exits via break */
-    i = p->pc++;
-    if( i>=nRow ){
-      p->rc = SQLITE_OK;
-      rc = SQLITE_DONE;
-      break;
-    }
-    if( i<p->nOp ){
-      /* The output line number is small enough that we are still in the
-      ** main program. */
-      pOp = &p->aOp[i];
-    }else{
-      /* We are currently listing subprograms.  Figure out which one and
-      ** pick up the appropriate opcode. */
-      int j;
-      i -= p->nOp;
-      assert( apSub!=0 );
-      assert( nSub>0 );
-      for(j=0; i>=apSub[j]->nOp; j++){
-        i -= apSub[j]->nOp;
-        assert( i<apSub[j]->nOp || j+1<nSub );
-      }
-      pOp = &apSub[j]->aOp[i];
-    }
-
-    /* When an OP_Program opcode is encounter (the only opcode that has
-    ** a P4_SUBPROGRAM argument), expand the size of the array of subprograms
-    ** kept in p->aMem[9].z to hold the new program - assuming this subprogram
-    ** has not already been seen.
-    */
-    if( bListSubprogs && pOp->p4type==P4_SUBPROGRAM ){
-      int nByte = (nSub+1)*sizeof(SubProgram*);
-      int j;
-      for(j=0; j<nSub; j++){
-        if( apSub[j]==pOp->p4.pProgram ) break;
-      }
-      if( j==nSub ){
-        p->rc = sqlite3VdbeMemGrow(pSub, nByte, nSub!=0);
-        if( p->rc!=SQLITE_OK ){
-          rc = SQLITE_ERROR;
-          break;
-        }
-        apSub = (SubProgram **)pSub->z;
-        apSub[nSub++] = pOp->p4.pProgram;
-        pSub->flags |= MEM_Blob;
-        pSub->n = nSub*sizeof(SubProgram*);
-        nRow += pOp->p4.pProgram->nOp;
-      }
-    }
-    if( p->explain<2 ) break;
-    if( pOp->opcode==OP_Explain ) break;
-    if( pOp->opcode==OP_Init && p->pc>1 ) break;
-  }
+  /* Figure out which opcode is next to display */
+  rc = sqlite3VdbeNextOpcode(p, pSub, p->explain==2, &p->pc, &i, &aOp);
 
   if( rc==SQLITE_OK ){
+    pOp = aOp + i;
     if( AtomicLoad(&db->u1.isInterrupted) ){
       p->rc = SQLITE_INTERRUPT;
       rc = SQLITE_ERROR;
       sqlite3VdbeError(p, sqlite3ErrStr(p->rc));
     }else{
-      char *zP4;
-      if( p->explain==1 ){
-        pMem->flags = MEM_Int;
-        pMem->u.i = i;                                /* Program counter */
-        pMem++;
-    
-        pMem->flags = MEM_Static|MEM_Str|MEM_Term;
-        pMem->z = (char*)sqlite3OpcodeName(pOp->opcode); /* Opcode */
-        assert( pMem->z!=0 );
-        pMem->n = sqlite3Strlen30(pMem->z);
-        pMem->enc = SQLITE_UTF8;
-        pMem++;
-      }
-
-      pMem->flags = MEM_Int;
-      pMem->u.i = pOp->p1;                          /* P1 */
-      pMem++;
-
-      pMem->flags = MEM_Int;
-      pMem->u.i = pOp->p2;                          /* P2 */
-      pMem++;
-
-      pMem->flags = MEM_Int;
-      pMem->u.i = pOp->p3;                          /* P3 */
-      pMem++;
-
-      if( sqlite3VdbeMemClearAndResize(pMem, 100) ){ /* P4 */
-        assert( p->db->mallocFailed );
-        return SQLITE_ERROR;
-      }
-      pMem->flags = MEM_Str|MEM_Term;
-      zP4 = displayP4(pOp, pMem->z, pMem->szMalloc);
-      if( zP4!=pMem->z ){
-        pMem->n = 0;
-        sqlite3VdbeMemSetStr(pMem, zP4, -1, SQLITE_UTF8, 0);
+      char *zP4 = sqlite3VdbeDisplayP4(db, pOp);
+      if( p->explain==2 ){
+        sqlite3VdbeMemSetInt64(pMem, pOp->p1);
+        sqlite3VdbeMemSetInt64(pMem+1, pOp->p2);
+        sqlite3VdbeMemSetInt64(pMem+2, pOp->p3);
+        sqlite3VdbeMemSetStr(pMem+3, zP4, -1, SQLITE_UTF8, sqlite3_free);     
+        p->nResColumn = 4;
       }else{
-        assert( pMem->z!=0 );
-        pMem->n = sqlite3Strlen30(pMem->z);
-        pMem->enc = SQLITE_UTF8;
-      }
-      pMem++;
-
-      if( p->explain==1 ){
-        if( sqlite3VdbeMemClearAndResize(pMem, 4) ){
-          assert( p->db->mallocFailed );
-          return SQLITE_ERROR;
-        }
-        pMem->flags = MEM_Str|MEM_Term;
-        pMem->n = 2;
-        sqlite3_snprintf(3, pMem->z, "%.2x", pOp->p5);   /* P5 */
-        pMem->enc = SQLITE_UTF8;
-        pMem++;
-    
+        sqlite3VdbeMemSetInt64(pMem+0, i);
+        sqlite3VdbeMemSetStr(pMem+1, (char*)sqlite3OpcodeName(pOp->opcode),
+                             -1, SQLITE_UTF8, SQLITE_STATIC);
+        sqlite3VdbeMemSetInt64(pMem+2, pOp->p1);
+        sqlite3VdbeMemSetInt64(pMem+3, pOp->p2);
+        sqlite3VdbeMemSetInt64(pMem+4, pOp->p3);
+        /* pMem+5 for p4 is done last */
+        sqlite3VdbeMemSetInt64(pMem+6, pOp->p5);
 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
-        if( sqlite3VdbeMemClearAndResize(pMem, 500) ){
-          assert( p->db->mallocFailed );
-          return SQLITE_ERROR;
+        {
+          char *zCom = sqlite3VdbeDisplayComment(db, pOp, zP4);
+          sqlite3VdbeMemSetStr(pMem+7, zCom, -1, SQLITE_UTF8, sqlite3_free);
         }
-        pMem->flags = MEM_Str|MEM_Term;
-        pMem->n = displayComment(pOp, zP4, pMem->z, 500);
-        pMem->enc = SQLITE_UTF8;
 #else
-        pMem->flags = MEM_Null;                       /* Comment */
+        sqlite3VdbeMemSetNull(pMem+7);
 #endif
+        sqlite3VdbeMemSetStr(pMem+5, zP4, -1, SQLITE_UTF8, sqlite3_free);
+        p->nResColumn = 8;
+      }
+      p->pResultSet = pMem;
+      if( db->mallocFailed ){
+        p->rc = SQLITE_NOMEM;
+        rc = SQLITE_ERROR;
+      }else{
+        p->rc = SQLITE_OK;
+        rc = SQLITE_ROW;
       }
-
-      p->nResColumn = 8 - 4*(p->explain-1);
-      p->pResultSet = &p->aMem[1];
-      p->rc = SQLITE_OK;
-      rc = SQLITE_ROW;
     }
   }
   return rc;

src/vdbevtab.c

@@ -0,0 +1,422 @@
+/*
+** 2020-03-23
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file implements virtual-tables for examining the bytecode content
+** of a prepared statement.
+*/
+#ifdef SQLITE_ENABLE_BYTECODE_VTAB
+#include "sqliteInt.h"
+#include "vdbeInt.h"
+
+/* An instance of the bytecode() table-valued function.
+*/
+typedef struct bytecodevtab bytecodevtab;
+struct bytecodevtab {
+  sqlite3_vtab base;     /* Base class - must be first */
+  sqlite3 *db;           /* Database connection */
+  int bTablesUsed;       /* 2 for tables_used().  0 for bytecode(). */
+};
+
+/* A cursor for scanning through the bytecode
+*/
+typedef struct bytecodevtab_cursor bytecodevtab_cursor;
+struct bytecodevtab_cursor {
+  sqlite3_vtab_cursor base;  /* Base class - must be first */
+  sqlite3_stmt *pStmt;       /* The statement whose bytecode is displayed */
+  int iRowid;                /* The rowid of the output table */
+  int iAddr;                 /* Address */
+  int needFinalize;          /* Cursors owns pStmt and must finalize it */
+  int showSubprograms;       /* Provide a listing of subprograms */
+  Op *aOp;                   /* Operand array */
+  char *zP4;                 /* Rendered P4 value */
+  const char *zType;         /* tables_used.type */
+  const char *zSchema;       /* tables_used.schema */
+  const char *zName;         /* tables_used.name */
+  Mem sub;                   /* Subprograms */
+};
+
+/*
+** Create a new bytecode() table-valued function.
+*/
+static int bytecodevtabConnect(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr
+){
+  bytecodevtab *pNew;
+  int rc;
+  int isTabUsed = pAux!=0;
+  const char *azSchema[2] = {
+    /* bytecode() schema */
+    "CREATE TABLE x("
+      "addr INT,"
+      "opcode TEXT,"
+      "p1 INT,"
+      "p2 INT,"
+      "p3 INT,"
+      "p4 TEXT,"
+      "p5 INT,"
+      "comment TEXT,"
+      "subprog TEXT," 
+      "stmt HIDDEN"
+    ");",
+
+    /* Tables_used() schema */
+    "CREATE TABLE x("
+      "type TEXT,"
+      "schema TEXT,"
+      "name TEXT,"
+      "wr INT,"
+      "subprog TEXT," 
+      "stmt HIDDEN"
+   ");"
+  };
+
+  rc = sqlite3_declare_vtab(db, azSchema[isTabUsed]);
+  if( rc==SQLITE_OK ){
+    pNew = sqlite3_malloc( sizeof(*pNew) );
+    *ppVtab = (sqlite3_vtab*)pNew;
+    if( pNew==0 ) return SQLITE_NOMEM;
+    memset(pNew, 0, sizeof(*pNew));
+    pNew->db = db;
+    pNew->bTablesUsed = isTabUsed*2;
+  }
+  return rc;
+}
+
+/*
+** This method is the destructor for bytecodevtab objects.
+*/
+static int bytecodevtabDisconnect(sqlite3_vtab *pVtab){
+  bytecodevtab *p = (bytecodevtab*)pVtab;
+  sqlite3_free(p);
+  return SQLITE_OK;
+}
+
+/*
+** Constructor for a new bytecodevtab_cursor object.
+*/
+static int bytecodevtabOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){
+  bytecodevtab *pVTab = (bytecodevtab*)p;
+  bytecodevtab_cursor *pCur;
+  pCur = sqlite3_malloc( sizeof(*pCur) );
+  if( pCur==0 ) return SQLITE_NOMEM;
+  memset(pCur, 0, sizeof(*pCur));
+  sqlite3VdbeMemInit(&pCur->sub, pVTab->db, 1);
+  *ppCursor = &pCur->base;
+  return SQLITE_OK;
+}
+
+/*
+** Clear all internal content from a bytecodevtab cursor.
+*/
+static void bytecodevtabCursorClear(bytecodevtab_cursor *pCur){
+  sqlite3_free(pCur->zP4);
+  pCur->zP4 = 0;
+  sqlite3VdbeMemRelease(&pCur->sub);
+  sqlite3VdbeMemSetNull(&pCur->sub);
+  if( pCur->needFinalize ){
+    sqlite3_finalize(pCur->pStmt);
+  }
+  pCur->pStmt = 0;
+  pCur->needFinalize = 0;
+  pCur->zType = 0;
+  pCur->zSchema = 0;
+  pCur->zName = 0;
+}
+
+/*
+** Destructor for a bytecodevtab_cursor.
+*/
+static int bytecodevtabClose(sqlite3_vtab_cursor *cur){
+  bytecodevtab_cursor *pCur = (bytecodevtab_cursor*)cur;
+  bytecodevtabCursorClear(pCur);
+  sqlite3_free(pCur);
+  return SQLITE_OK;
+}
+
+
+/*
+** Advance a bytecodevtab_cursor to its next row of output.
+*/
+static int bytecodevtabNext(sqlite3_vtab_cursor *cur){
+  bytecodevtab_cursor *pCur = (bytecodevtab_cursor*)cur;
+  bytecodevtab *pTab = (bytecodevtab*)cur->pVtab;
+  int rc;
+  if( pCur->zP4 ){
+    sqlite3_free(pCur->zP4);
+    pCur->zP4 = 0;
+  }
+  if( pCur->zName ){
+    pCur->zName = 0;
+    pCur->zType = 0;
+    pCur->zSchema = 0;
+  }
+  rc = sqlite3VdbeNextOpcode(
+           (Vdbe*)pCur->pStmt, 
+           pCur->showSubprograms ? &pCur->sub : 0,
+           pTab->bTablesUsed,
+           &pCur->iRowid,
+           &pCur->iAddr,
+           &pCur->aOp);
+  if( rc!=SQLITE_OK ){
+    sqlite3VdbeMemSetNull(&pCur->sub);
+    pCur->aOp = 0;
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Return TRUE if the cursor has been moved off of the last
+** row of output.
+*/
+static int bytecodevtabEof(sqlite3_vtab_cursor *cur){
+  bytecodevtab_cursor *pCur = (bytecodevtab_cursor*)cur;
+  return pCur->aOp==0;
+}
+
+/*
+** Return values of columns for the row at which the bytecodevtab_cursor
+** is currently pointing.
+*/
+static int bytecodevtabColumn(
+  sqlite3_vtab_cursor *cur,   /* The cursor */
+  sqlite3_context *ctx,       /* First argument to sqlite3_result_...() */
+  int i                       /* Which column to return */
+){
+  bytecodevtab_cursor *pCur = (bytecodevtab_cursor*)cur;
+  bytecodevtab *pVTab = (bytecodevtab*)cur->pVtab;
+  Op *pOp = pCur->aOp + pCur->iAddr;
+  if( pVTab->bTablesUsed ){
+    if( i==4 ){
+      i = 8;
+    }else{
+      if( i<=2 && pCur->zType==0 ){
+        Schema *pSchema;
+        HashElem *k;
+        int iDb = pOp->p3;
+        int iRoot = pOp->p2;
+        sqlite3 *db = pVTab->db;
+        pSchema = db->aDb[iDb].pSchema;
+        pCur->zSchema = db->aDb[iDb].zDbSName;
+        for(k=sqliteHashFirst(&pSchema->tblHash); k; k=sqliteHashNext(k)){
+          Table *pTab = (Table*)sqliteHashData(k);
+          if( !IsVirtual(pTab) && pTab->tnum==iRoot ){
+            pCur->zName = pTab->zName;
+            pCur->zType = "table";
+            break;
+          }
+        }
+        if( pCur->zName==0 ){
+          for(k=sqliteHashFirst(&pSchema->idxHash); k; k=sqliteHashNext(k)){
+            Index *pIdx = (Index*)sqliteHashData(k);
+            if( pIdx->tnum==iRoot ){
+              pCur->zName = pIdx->zName;
+              pCur->zType = "index";
+            }
+          }
+        }
+      }
+      i += 10;
+    }
+  }
+  switch( i ){
+    case 0:   /* addr */
+      sqlite3_result_int(ctx, pCur->iAddr);
+      break;
+    case 1:   /* opcode */
+      sqlite3_result_text(ctx, (char*)sqlite3OpcodeName(pOp->opcode),
+                          -1, SQLITE_STATIC);
+      break;
+    case 2:   /* p1 */
+      sqlite3_result_int(ctx, pOp->p1);
+      break;
+    case 3:   /* p2 */
+      sqlite3_result_int(ctx, pOp->p2);
+      break;
+    case 4:   /* p3 */
+      sqlite3_result_int(ctx, pOp->p3);
+      break;
+    case 5:   /* p4 */
+    case 7:   /* comment */
+      if( pCur->zP4==0 ){
+        pCur->zP4 = sqlite3VdbeDisplayP4(pVTab->db, pOp);
+      }
+      if( i==5 ){
+        sqlite3_result_text(ctx, pCur->zP4, -1, SQLITE_STATIC);
+      }else{
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
+        char *zCom = sqlite3VdbeDisplayComment(pVTab->db, pOp, pCur->zP4);
+        sqlite3_result_text(ctx, zCom, -1, sqlite3_free);
+#endif
+      }
+      break;
+    case 6:     /* p5 */
+      sqlite3_result_int(ctx, pOp->p5);
+      break;
+    case 8: {   /* subprog */
+      Op *aOp = pCur->aOp;
+      assert( aOp[0].opcode==OP_Init );
+      assert( aOp[0].p4.z==0 || strncmp(aOp[0].p4.z,"-" "- ",3)==0 );
+      if( pCur->iRowid==pCur->iAddr+1 ){
+        break;  /* Result is NULL for the main program */
+      }else if( aOp[0].p4.z!=0 ){
+         sqlite3_result_text(ctx, aOp[0].p4.z+3, -1, SQLITE_STATIC);
+      }else{
+         sqlite3_result_text(ctx, "(FK)", 4, SQLITE_STATIC);
+      }
+      break;
+    }
+    case 10:  /* tables_used.type */
+      sqlite3_result_text(ctx, pCur->zType, -1, SQLITE_STATIC);
+      break;
+    case 11:  /* tables_used.schema */
+      sqlite3_result_text(ctx, pCur->zSchema, -1, SQLITE_STATIC);
+      break;
+    case 12:  /* tables_used.name */
+      sqlite3_result_text(ctx, pCur->zName, -1, SQLITE_STATIC);
+      break;
+    case 13:  /* tables_used.wr */
+      sqlite3_result_int(ctx, pOp->opcode==OP_OpenWrite);
+      break;
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Return the rowid for the current row.  In this implementation, the
+** rowid is the same as the output value.
+*/
+static int bytecodevtabRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
+  bytecodevtab_cursor *pCur = (bytecodevtab_cursor*)cur;
+  *pRowid = pCur->iRowid;
+  return SQLITE_OK;
+}
+
+/*
+** Initialize a cursor.
+**
+**    idxNum==0     means show all subprograms
+**    idxNum==1     means show only the main bytecode and omit subprograms.
+*/
+static int bytecodevtabFilter(
+  sqlite3_vtab_cursor *pVtabCursor, 
+  int idxNum, const char *idxStr,
+  int argc, sqlite3_value **argv
+){
+  bytecodevtab_cursor *pCur = (bytecodevtab_cursor *)pVtabCursor;
+  bytecodevtab *pVTab = (bytecodevtab *)pVtabCursor->pVtab;
+  int rc = SQLITE_OK;
+
+  bytecodevtabCursorClear(pCur);
+  pCur->iRowid = 0;
+  pCur->iAddr = 0;
+  pCur->showSubprograms = idxNum==0;
+  assert( argc==1 );
+  if( sqlite3_value_type(argv[0])==SQLITE_TEXT ){
+    const char *zSql = (const char*)sqlite3_value_text(argv[0]);
+    if( zSql==0 ){
+      rc = SQLITE_NOMEM;
+    }else{
+      rc = sqlite3_prepare_v2(pVTab->db, zSql, -1, &pCur->pStmt, 0);
+      pCur->needFinalize = 1;
+    }
+  }else{
+    pCur->pStmt = (sqlite3_stmt*)sqlite3_value_pointer(argv[0],"stmt-pointer");
+  }
+  if( pCur->pStmt==0 ){
+    pVTab->base.zErrMsg = sqlite3_mprintf(
+       "argument to %s() is not a valid SQL statement",
+       pVTab->bTablesUsed ? "tables_used" : "bytecode"
+    );
+    rc = SQLITE_ERROR;
+  }else{
+    bytecodevtabNext(pVtabCursor);
+  }
+  return rc;
+}
+
+/*
+** We must have a single stmt=? constraint that will be passed through
+** into the xFilter method.  If there is no valid stmt=? constraint,
+** then return an SQLITE_CONSTRAINT error.
+*/
+static int bytecodevtabBestIndex(
+  sqlite3_vtab *tab,
+  sqlite3_index_info *pIdxInfo
+){
+  int i;
+  int rc = SQLITE_CONSTRAINT;
+  struct sqlite3_index_constraint *p;
+  bytecodevtab *pVTab = (bytecodevtab*)tab;
+  int iBaseCol = pVTab->bTablesUsed ? 4 : 8;
+  pIdxInfo->estimatedCost = (double)100;
+  pIdxInfo->estimatedRows = 100;
+  pIdxInfo->idxNum = 0;
+  for(i=0, p=pIdxInfo->aConstraint; i<pIdxInfo->nConstraint; i++, p++){
+    if( p->usable==0 ) continue;
+    if( p->op==SQLITE_INDEX_CONSTRAINT_EQ && p->iColumn==iBaseCol+1 ){
+      rc = SQLITE_OK;
+      pIdxInfo->aConstraintUsage[i].omit = 1;
+      pIdxInfo->aConstraintUsage[i].argvIndex = 1;
+    }
+    if( p->op==SQLITE_INDEX_CONSTRAINT_ISNULL && p->iColumn==iBaseCol ){
+      pIdxInfo->aConstraintUsage[i].omit = 1;
+      pIdxInfo->idxNum = 1;
+    }
+  }
+  return rc;
+}
+
+/*
+** This following structure defines all the methods for the 
+** virtual table.
+*/
+static sqlite3_module bytecodevtabModule = {
+  /* iVersion    */ 0,
+  /* xCreate     */ 0,
+  /* xConnect    */ bytecodevtabConnect,
+  /* xBestIndex  */ bytecodevtabBestIndex,
+  /* xDisconnect */ bytecodevtabDisconnect,
+  /* xDestroy    */ 0,
+  /* xOpen       */ bytecodevtabOpen,
+  /* xClose      */ bytecodevtabClose,
+  /* xFilter     */ bytecodevtabFilter,
+  /* xNext       */ bytecodevtabNext,
+  /* xEof        */ bytecodevtabEof,
+  /* xColumn     */ bytecodevtabColumn,
+  /* xRowid      */ bytecodevtabRowid,
+  /* xUpdate     */ 0,
+  /* xBegin      */ 0,
+  /* xSync       */ 0,
+  /* xCommit     */ 0,
+  /* xRollback   */ 0,
+  /* xFindMethod */ 0,
+  /* xRename     */ 0,
+  /* xSavepoint  */ 0,
+  /* xRelease    */ 0,
+  /* xRollbackTo */ 0,
+  /* xShadowName */ 0
+};
+
+
+int sqlite3VdbeBytecodeVtabInit(sqlite3 *db){
+  int rc;
+  rc = sqlite3_create_module(db, "bytecode", &bytecodevtabModule, 0);
+  if( rc==SQLITE_OK ){
+    rc = sqlite3_create_module(db, "tables_used", &bytecodevtabModule, &db);
+  }
+  return rc;
+}
+#endif /* SQLITE_ENABLE_BYTECODE_VTAB */

test/distinct.test

@@ -51,8 +51,8 @@ proc do_temptables_test {tn sql temptables} {
     set ret ""
     db eval "EXPLAIN [set sql]" {
       if {$opcode == "OpenEphemeral" || $opcode == "SorterOpen"} { 
-        if {$p5 != "08" && $p5!="00"} { error "p5 = $p5" }
-        if {$p5 == "08"} {
+        if {$p5!=8 && $p5!=0} { error "p5 = $p5" }
+        if {$p5==8} {
           lappend ret hash
         } else {
           lappend ret btree

test/fts3misc.test

@@ -315,4 +315,12 @@ do_catchsql_test 10.1 {
   INSERT INTO f(f) VALUES ('merge=69,59');
 } {1 {database disk image is malformed}}
 
+#-------------------------------------------------------------------------
+do_execsql_test 11.0 {
+  CREATE VIRTUAL TABLE xyz USING fts3();
+}
+do_execsql_test 11.1 {
+  SELECT * FROM xyz WHERE xyz MATCH 'a NEAR/4294836224 a';
+}
+
 finish_test

test/join2.test

@@ -293,5 +293,36 @@ do_execsql_test 8.1 {
   WHERE (t1.c0 BETWEEN 0 AND 0) > ('' AND t0.c0);
 }
 
+#-------------------------------------------------------------------------
+# Ticket [45f4bf4eb].
+#
+reset_db
+do_execsql_test 9.0 {
+  CREATE TABLE t0(c0 INT);
+  CREATE VIEW v0(c0) AS SELECT CAST(t0.c0 AS INTEGER) FROM t0;
+  INSERT INTO t0(c0) VALUES (0);
+}
+
+do_execsql_test 9.1 {
+  SELECT typeof(c0), c0 FROM v0 WHERE c0>='0'
+} {integer 0}
+
+do_execsql_test 9.2 {
+  SELECT * FROM t0, v0 WHERE v0.c0 >= '0';
+} {0 0}
+
+do_execsql_test 9.3 {
+  SELECT * FROM t0 LEFT JOIN v0 WHERE v0.c0 >= '0';
+} {0 0}
+
+do_execsql_test 9.4 {
+  SELECT * FROM t0 LEFT JOIN v0 ON v0.c0 >= '0';
+} {0 0}
+
+do_execsql_test 9.5 {
+  SELECT * FROM t0 LEFT JOIN v0 ON v0.c0 >= '0' WHERE TRUE 
+  UNION SELECT 0,0 WHERE 0; 
+} {0 0}
+
 
 finish_test

test/whereL.test

@@ -157,4 +157,38 @@ do_execsql_test 600 {
    WHERE x='good' AND y='good';
 } {good good}
 
+# 2020-04-24: Another test case for the previous (1dcb4d44964846ad)
+# ticket.  The test case comes from 
+# https://stackoverflow.com/questions/61399253/sqlite3-different-result-in-console-compared-to-python-script/
+# Output verified against postgresql.
+#
+do_execsql_test 610 {
+  CREATE TABLE tableA(
+    ID           int,
+    RunYearMonth int
+  );
+  INSERT INTO tableA VALUES(1,202003),(2,202003),(3,202003),(4,202004),
+    (5,202004),(6,202004),(7,202004),(8,202004);
+  CREATE TABLE tableB (
+    ID           int,
+    RunYearMonth int
+  );
+  INSERT INTO tableB VALUES(1,202004),(2,202004),(3,202004),(4,202004),
+  (5,202004);
+  SELECT *
+   FROM (
+        SELECT *
+        FROM tableA
+        WHERE RunYearMonth = 202004
+    ) AS A
+    INNER JOIN (
+        SELECT *
+        FROM tableB
+        WHERE RunYearMonth = 202004
+    ) AS B
+    ON A.ID = B.ID
+    AND A.RunYearMonth = B.RunYearMonth;
+} {4 202004 4 202004 5 202004 5 202004}
+
+
 finish_test

tool/mksqlite3c.tcl

@@ -341,6 +341,7 @@ foreach file {
    vdbe.c
    vdbeblob.c
    vdbesort.c
+   vdbevtab.c
    memjournal.c
 
    walker.c

tool/spaceanal.tcl

@@ -587,6 +587,9 @@ set free_percent2 [percent $free_pgcnt2 $file_pgcnt]
 
 set file_pgcnt2 [expr {$inuse_pgcnt+$free_pgcnt2+$av_pgcnt}]
 
+# Account for the lockbyte page
+if {$file_pgcnt2*$pageSize>1073742335} {incr file_pgcnt2}
+
 set ntable [db eval {SELECT count(*)+1 FROM sqlite_master WHERE type='table'}]
 set nindex [db eval {SELECT count(*) FROM sqlite_master WHERE type='index'}]
 set sql {SELECT count(*) FROM sqlite_master WHERE name LIKE 'sqlite_autoindex%'}