Improve text-to-integer conversion in boundary cases. The

sqlite3Atoi64() function always returns the minimum or maximum integer
if the magnitude of the text value is too large.  Trailing whitespace is
now ignored.

FossilOrigin-Name: ace0644a1a2a42a3ea42d44f00a31915b8a7e56c9ba90f90a6c02001f89f9c86

1 files changed, 28 insertions, 24 deletions

diff --git a/src/util.c b/src/util.c
index 456317cfa..9954d709d 100644
--- a/src/util.c
+++ b/src/util.c
@@ -595,7 +595,7 @@ static int compare2pow63(const char *zNum, int incr){
 ** Returns:
 **
 **     0    Successful transformation.  Fits in a 64-bit signed integer.
-**     1    Excess text after the integer value
+**     1    Excess non-space text after the integer value
 **     2    Integer too large for a 64-bit signed integer or is malformed
 **     3    Special case of 9223372036854775808
 **
@@ -638,47 +638,51 @@ int sqlite3Atoi64(const char *zNum, i64 *pNum, int length, u8 enc){
   for(i=0; &zNum[i]<zEnd && (c=zNum[i])>='0' && c<='9'; i+=incr){
     u = u*10 + c - '0';
   }
-  if( u>LARGEST_INT64 ){
-    *pNum = neg ? SMALLEST_INT64 : LARGEST_INT64;
-  }else if( neg ){
+  testcase( i==18*incr );
+  testcase( i==19*incr );
+  testcase( i==20*incr );
+  if( neg ){
     *pNum = -(i64)u;
   }else{
     *pNum = (i64)u;
   }
-  testcase( i==18 );
-  testcase( i==19 );
-  testcase( i==20 );
-  if( &zNum[i]<zEnd              /* Extra bytes at the end */
-   || (i==0 && zStart==zNum)     /* No digits */
+  rc = 0;
+  if( (i==0 && zStart==zNum)     /* No digits */
    || nonNum                     /* UTF16 with high-order bytes non-zero */
   ){
     rc = 1;
-  }else{
-    rc = 0;
+  }else if( &zNum[i]<zEnd ){     /* Extra bytes at the end */
+    int jj = i;
+    do{
+      if( !sqlite3Isspace(zNum[jj]) ){
+        rc = 1;          /* Extra non-space text after the integer */
+        break;
+      }
+      jj += incr;
+    }while( &zNum[jj]<zEnd );
   }
-  if( i>19*incr ){                /* Too many digits */
-    /* zNum is empty or contains non-numeric text or is longer
-    ** than 19 digits (thus guaranteeing that it is too large) */
-    return 2;
-  }else if( i<19*incr ){
+  if( i<19*incr ){
     /* Less than 19 digits, so we know that it fits in 64 bits */
     assert( u<=LARGEST_INT64 );
     return rc;
   }else{
     /* zNum is a 19-digit numbers.  Compare it against 9223372036854775808. */
-    c = compare2pow63(zNum, incr);
+    c = i>19*incr ? 1 : compare2pow63(zNum, incr);
     if( c<0 ){
       /* zNum is less than 9223372036854775808 so it fits */
       assert( u<=LARGEST_INT64 );
       return rc;
-    }else if( c>0 ){
-      /* zNum is greater than 9223372036854775808 so it overflows */
-      return 2;
     }else{
-      /* zNum is exactly 9223372036854775808.  Fits if negative.  The
-      ** special case 2 overflow if positive */
-      assert( u-1==LARGEST_INT64 );
-      return neg ? rc : 3;
+      *pNum = neg ? SMALLEST_INT64 : LARGEST_INT64;
+      if( c>0 ){
+        /* zNum is greater than 9223372036854775808 so it overflows */
+        return 2;
+      }else{
+        /* zNum is exactly 9223372036854775808.  Fits if negative.  The
+        ** special case 2 overflow if positive */
+        assert( u-1==LARGEST_INT64 );
+        return neg ? rc : 3;
+      }
     }
   }
 }