tursodatabase
diff --git a/‎libsql-ffi/bundled/SQLite3MultipleCiphers/src/fileio.c‎
Lines changed: 16 additions & 8 deletions b/‎libsql-ffi/bundled/SQLite3MultipleCiphers/src/fileio.c‎
Lines changed: 16 additions & 8 deletions
diff --git a/‎libsql-ffi/bundled/SQLite3MultipleCiphers/src/series.c‎
Lines changed: 88 additions & 32 deletions b/‎libsql-ffi/bundled/SQLite3MultipleCiphers/src/series.c‎
Lines changed: 88 additions & 32 deletions
@@ -372,7 +372,9 @@ static int writeFile(
 #if !defined(_WIN32) && !defined(WIN32)
   if( S_ISLNK(mode) ){
     const char *zTo = (const char*)sqlite3_value_text(pData);
-    if( zTo==0 || symlink(zTo, zFile)<0 ) return 1;
+    if( zTo==0 ) return 1;
+    unlink(zFile);
+    if( symlink(zTo, zFile)<0 ) return 1;
   }else
 #endif
   {
@@ -458,13 +460,19 @@ static int writeFile(
       return 1;
     }
 #else
-    /* Legacy unix */
-    struct timeval times[2];
-    times[0].tv_usec = times[1].tv_usec = 0;
-    times[0].tv_sec = time(0);
-    times[1].tv_sec = mtime;
-    if( utimes(zFile, times) ){
-      return 1;
+    /* Legacy unix. 
+    **
+    ** Do not use utimes() on a symbolic link - it sees through the link and
+    ** modifies the timestamps on the target. Or fails if the target does 
+    ** not exist.  */
+    if( 0==S_ISLNK(mode) ){
+      struct timeval times[2];
+      times[0].tv_usec = times[1].tv_usec = 0;
+      times[0].tv_sec = time(0);
+      times[1].tv_sec = mtime;
+      if( utimes(zFile, times) ){
+        return 1;
+      }
     }
 #endif
   }
 
@@ -103,16 +103,20 @@ SQLITE_EXTENSION_INIT1
 ** index is ix. The 0th member is given by smBase. The sequence members
 ** progress per ix increment by smStep.
 */
-static sqlite3_int64 genSeqMember(sqlite3_int64 smBase,
-                                  sqlite3_int64 smStep,
-                                  sqlite3_uint64 ix){
-  if( ix>=(sqlite3_uint64)LLONG_MAX ){
+static sqlite3_int64 genSeqMember(
+  sqlite3_int64 smBase,
+  sqlite3_int64 smStep,
+  sqlite3_uint64 ix
+){
+  static const sqlite3_uint64 mxI64 =
+      ((sqlite3_uint64)0x7fffffff)<<32 | 0xffffffff;
+  if( ix>=mxI64 ){
     /* Get ix into signed i64 range. */
-    ix -= (sqlite3_uint64)LLONG_MAX;
+    ix -= mxI64;
     /* With 2's complement ALU, this next can be 1 step, but is split into
      * 2 for UBSAN's satisfaction (and hypothetical 1's complement ALUs.) */
-    smBase += (LLONG_MAX/2) * smStep;
-    smBase += (LLONG_MAX - LLONG_MAX/2) * smStep;
+    smBase += (mxI64/2) * smStep;
+    smBase += (mxI64 - mxI64/2) * smStep;
   }
   /* Under UBSAN (or on 1's complement machines), must do this last term
    * in steps to avoid the dreaded (and harmless) signed multiply overlow. */
@@ -372,13 +376,13 @@ static int seriesEof(sqlite3_vtab_cursor *cur){
 ** parameter.  (idxStr is not used in this implementation.)  idxNum
 ** is a bitmask showing which constraints are available:
 **
-**    1:    start=VALUE
-**    2:    stop=VALUE
-**    4:    step=VALUE
-**
-** Also, if bit 8 is set, that means that the series should be output
-** in descending order rather than in ascending order.  If bit 16 is
-** set, then output must appear in ascending order.
+**   0x01:    start=VALUE
+**   0x02:    stop=VALUE
+**   0x04:    step=VALUE
+**   0x08:    descending order
+**   0x10:    ascending order
+**   0x20:    LIMIT  VALUE
+**   0x40:    OFFSET  VALUE
 **
 ** This routine should initialize the cursor and position it so that it
 ** is pointing at the first row, or pointing off the end of the table
@@ -392,26 +396,44 @@ static int seriesFilter(
   series_cursor *pCur = (series_cursor *)pVtabCursor;
   int i = 0;
   (void)idxStrUnused;
-  if( idxNum & 1 ){
+  if( idxNum & 0x01 ){
     pCur->ss.iBase = sqlite3_value_int64(argv[i++]);
   }else{
     pCur->ss.iBase = 0;
   }
-  if( idxNum & 2 ){
+  if( idxNum & 0x02 ){
     pCur->ss.iTerm = sqlite3_value_int64(argv[i++]);
   }else{
     pCur->ss.iTerm = 0xffffffff;
   }
-  if( idxNum & 4 ){
+  if( idxNum & 0x04 ){
     pCur->ss.iStep = sqlite3_value_int64(argv[i++]);
     if( pCur->ss.iStep==0 ){
       pCur->ss.iStep = 1;
     }else if( pCur->ss.iStep<0 ){
-      if( (idxNum & 16)==0 ) idxNum |= 8;
+      if( (idxNum & 0x10)==0 ) idxNum |= 0x08;
     }
   }else{
     pCur->ss.iStep = 1;
   }
+  if( idxNum & 0x20 ){
+    sqlite3_int64 iLimit = sqlite3_value_int64(argv[i++]);
+    sqlite3_int64 iTerm;
+    if( idxNum & 0x40 ){
+      sqlite3_int64 iOffset = sqlite3_value_int64(argv[i++]);
+      if( iOffset>0 ){
+        pCur->ss.iBase += pCur->ss.iStep*iOffset;
+      }
+    }
+    if( iLimit>=0 ){
+      iTerm = pCur->ss.iBase + (iLimit - 1)*pCur->ss.iStep;
+      if( pCur->ss.iStep<0 ){
+        if( iTerm>pCur->ss.iTerm ) pCur->ss.iTerm = iTerm;
+      }else{
+        if( iTerm<pCur->ss.iTerm ) pCur->ss.iTerm = iTerm;
+      }
+    }
+  }
   for(i=0; i<argc; i++){
     if( sqlite3_value_type(argv[i])==SQLITE_NULL ){
       /* If any of the constraints have a NULL value, then return no rows.
@@ -422,7 +444,7 @@ static int seriesFilter(
       break;
     }
   }
-  if( idxNum & 8 ){
+  if( idxNum & 0x08 ){
     pCur->ss.isReversing = pCur->ss.iStep > 0;
   }else{
     pCur->ss.isReversing = pCur->ss.iStep < 0;
@@ -442,50 +464,81 @@ static int seriesFilter(
 **
 ** The query plan is represented by bits in idxNum:
 **
-**  (1)  start = $value  -- constraint exists
-**  (2)  stop = $value   -- constraint exists
-**  (4)  step = $value   -- constraint exists
-**  (8)  output in descending order
+**   0x01  start = $value  -- constraint exists
+**   0x02  stop = $value   -- constraint exists
+**   0x04  step = $value   -- constraint exists
+**   0x08  output is in descending order
+**   0x10  output is in ascending order
+**   0x20  LIMIT $value    -- constraint exists
+**   0x40  OFFSET $value   -- constraint exists
 */
 static int seriesBestIndex(
   sqlite3_vtab *pVTab,
   sqlite3_index_info *pIdxInfo
 ){
   int i, j;              /* Loop over constraints */
   int idxNum = 0;        /* The query plan bitmask */
+#ifndef ZERO_ARGUMENT_GENERATE_SERIES
   int bStartSeen = 0;    /* EQ constraint seen on the START column */
+#endif
   int unusableMask = 0;  /* Mask of unusable constraints */
   int nArg = 0;          /* Number of arguments that seriesFilter() expects */
-  int aIdx[3];           /* Constraints on start, stop, and step */
+  int aIdx[5];           /* Constraints on start, stop, step, LIMIT, OFFSET */
   const struct sqlite3_index_constraint *pConstraint;
 
   /* This implementation assumes that the start, stop, and step columns
   ** are the last three columns in the virtual table. */
   assert( SERIES_COLUMN_STOP == SERIES_COLUMN_START+1 );
   assert( SERIES_COLUMN_STEP == SERIES_COLUMN_START+2 );
 
-  aIdx[0] = aIdx[1] = aIdx[2] = -1;
+  aIdx[0] = aIdx[1] = aIdx[2] = aIdx[3] = aIdx[4] = -1;
   pConstraint = pIdxInfo->aConstraint;
   for(i=0; i<pIdxInfo->nConstraint; i++, pConstraint++){
     int iCol;    /* 0 for start, 1 for stop, 2 for step */
     int iMask;   /* bitmask for those column */
+    int op = pConstraint->op;
+    if( op>=SQLITE_INDEX_CONSTRAINT_LIMIT
+     && op<=SQLITE_INDEX_CONSTRAINT_OFFSET
+    ){
+      if( pConstraint->usable==0 ){
+        /* do nothing */
+      }else if( op==SQLITE_INDEX_CONSTRAINT_LIMIT ){
+        aIdx[3] = i;
+        idxNum |= 0x20;
+      }else{
+        assert( op==SQLITE_INDEX_CONSTRAINT_OFFSET );
+        aIdx[4] = i;
+        idxNum |= 0x40;
+      }
+      continue;
+    }
     if( pConstraint->iColumn<SERIES_COLUMN_START ) continue;
     iCol = pConstraint->iColumn - SERIES_COLUMN_START;
     assert( iCol>=0 && iCol<=2 );
     iMask = 1 << iCol;
-    if( iCol==0 ) bStartSeen = 1;
+#ifndef ZERO_ARGUMENT_GENERATE_SERIES
+    if( iCol==0 && op==SQLITE_INDEX_CONSTRAINT_EQ ){
+      bStartSeen = 1;
+    }
+#endif
     if( pConstraint->usable==0 ){
       unusableMask |=  iMask;
       continue;
-    }else if( pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ ){
+    }else if( op==SQLITE_INDEX_CONSTRAINT_EQ ){
       idxNum |= iMask;
       aIdx[iCol] = i;
     }
   }
-  for(i=0; i<3; i++){
+  if( aIdx[3]==0 ){
+    /* Ignore OFFSET if LIMIT is omitted */
+    idxNum &= ~0x60;
+    aIdx[4] = 0;
+  }
+  for(i=0; i<5; i++){
     if( (j = aIdx[i])>=0 ){
       pIdxInfo->aConstraintUsage[j].argvIndex = ++nArg;
-      pIdxInfo->aConstraintUsage[j].omit = !SQLITE_SERIES_CONSTRAINT_VERIFY;
+      pIdxInfo->aConstraintUsage[j].omit =
+         !SQLITE_SERIES_CONSTRAINT_VERIFY || i>=3;
     }
   }
   /* The current generate_column() implementation requires at least one
@@ -506,19 +559,22 @@ static int seriesBestIndex(
     ** this plan is unusable */
     return SQLITE_CONSTRAINT;
   }
-  if( (idxNum & 3)==3 ){
+  if( (idxNum & 0x03)==0x03 ){
     /* Both start= and stop= boundaries are available.  This is the 
     ** the preferred case */
     pIdxInfo->estimatedCost = (double)(2 - ((idxNum&4)!=0));
     pIdxInfo->estimatedRows = 1000;
     if( pIdxInfo->nOrderBy>=1 && pIdxInfo->aOrderBy[0].iColumn==0 ){
       if( pIdxInfo->aOrderBy[0].desc ){
-        idxNum |= 8;
+        idxNum |= 0x08;
       }else{
-        idxNum |= 16;
+        idxNum |= 0x10;
       }
       pIdxInfo->orderByConsumed = 1;
     }
+  }else if( (idxNum & 0x21)==0x21 ){
+    /* We have start= and LIMIT */
+    pIdxInfo->estimatedRows = 2500;
   }else{
     /* If either boundary is missing, we have to generate a huge span
     ** of numbers.  Make this case very expensive so that the query