[sql] Import reference version of SQLite 3.8.7.4.

third_party/sqlite/sqlite-src-3080704/src/bitvec.c

 /*
 ** 2008 February 16
 **
 ** 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.
 **
@@ skipping 54 matching lines @@
 ** (an arbitrary prime)in the hash function provided 
 ** no fewer collisions than the no-op *1. */
 #define BITVEC_HASH(X)   (((X)*1)%BITVEC_NINT)
 
 #define BITVEC_NPTR      (BITVEC_USIZE/sizeof(Bitvec *))
 
 
 /*
 ** A bitmap is an instance of the following structure.
 **
-** This bitmap records the existance of zero or more bits
+** This bitmap records the existence of zero or more bits
 ** with values between 1 and iSize, inclusive.
 **
 ** There are three possible representations of the bitmap.
 ** If iSize<=BITVEC_NBIT, then Bitvec.u.aBitmap[] is a straight
 ** bitmap.  The least significant bit is bit 1.
 **
 ** If iSize>BITVEC_NBIT and iDivisor==0 then Bitvec.u.aHash[] is
 ** a hash table that will hold up to BITVEC_MXHASH distinct values.
 **
 ** Otherwise, the value i is redirected into one of BITVEC_NPTR
@@ skipping 247 matching lines @@
 int sqlite3BitvecBuiltinTest(int sz, int *aOp){
   Bitvec *pBitvec = 0;
   unsigned char *pV = 0;
   int rc = -1;
   int i, nx, pc, op;
   void *pTmpSpace;
 
   /* Allocate the Bitvec to be tested and a linear array of
   ** bits to act as the reference */
   pBitvec = sqlite3BitvecCreate( sz );
-  pV = sqlite3_malloc( (sz+7)/8 + 1 );
+  pV = sqlite3MallocZero( (sz+7)/8 + 1 );
   pTmpSpace = sqlite3_malloc(BITVEC_SZ);
   if( pBitvec==0 || pV==0 || pTmpSpace==0  ) goto bitvec_end;
-  memset(pV, 0, (sz+7)/8 + 1);
 
   /* NULL pBitvec tests */
   sqlite3BitvecSet(0, 1);
   sqlite3BitvecClear(0, 1, pTmpSpace);
 
   /* Run the program */
   pc = 0;
   while( (op = aOp[pc])!=0 ){
     switch( op ){
       case 1:
@@ skipping 42 matching lines @@
   }
 
   /* Free allocated structure */
 bitvec_end:
   sqlite3_free(pTmpSpace);
   sqlite3_free(pV);
   sqlite3BitvecDestroy(pBitvec);
   return rc;
 }
 #endif /* SQLITE_OMIT_BUILTIN_TEST */