Import SQLite 3.7.6.3.

third_party/sqlite/src/src/func.c

Index: third_party/sqlite/src/src/func.c
diff --git a/third_party/sqlite/src/src/func.c b/third_party/sqlite/src/src/func.c
index 2b31af216d0d3a4bd401f6902cafbcead07e87fb..ed6a1e809f11035cf5d6ff3b2d5d0312304228e3 100644
--- a/third_party/sqlite/src/src/func.c
+++ b/third_party/sqlite/src/src/func.c
@@ -117,7 +117,10 @@ static void lengthFunc(
 }
 
 /*
-** Implementation of the abs() function
+** Implementation of the abs() function.
+**
+** IMP: R-23979-26855 The abs(X) function returns the absolute value of
+** the numeric argument X. 
 */
 static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
   assert( argc==1 );
@@ -127,6 +130,9 @@ static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
       i64 iVal = sqlite3_value_int64(argv[0]);
       if( iVal<0 ){
         if( (iVal<<1)==0 ){
+          /* IMP: R-35460-15084 If X is the integer -9223372036854775807 then
+          ** abs(X) throws an integer overflow error since there is no
+          ** equivalent positive 64-bit two complement value. */
           sqlite3_result_error(context, "integer overflow", -1);
           return;
         }
@@ -136,10 +142,16 @@ static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
       break;
     }
     case SQLITE_NULL: {
+      /* IMP: R-37434-19929 Abs(X) returns NULL if X is NULL. */
       sqlite3_result_null(context);
       break;
     }
     default: {
+      /* Because sqlite3_value_double() returns 0.0 if the argument is not
+      ** something that can be converted into a number, we have:
+      ** IMP: R-57326-31541 Abs(X) return 0.0 if X is a string or blob that
+      ** cannot be converted to a numeric value. 
+      */
       double rVal = sqlite3_value_double(argv[0]);
       if( rVal<0 ) rVal = -rVal;
       sqlite3_result_double(context, rVal);
@@ -157,6 +169,8 @@ static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
 ** If x is a blob, then we count bytes.
 **
 ** If p1 is negative, then we begin abs(p1) from the end of x[].
+**
+** If p2 is negative, return the p2 characters preceeding p1.
 */
 static void substrFunc(
   sqlite3_context *context,
@@ -177,6 +191,7 @@ static void substrFunc(
     return;
   }
   p0type = sqlite3_value_type(argv[0]);
+  p1 = sqlite3_value_int(argv[1]);
   if( p0type==SQLITE_BLOB ){
     len = sqlite3_value_bytes(argv[0]);
     z = sqlite3_value_blob(argv[0]);
@@ -186,11 +201,12 @@ static void substrFunc(
     z = sqlite3_value_text(argv[0]);
     if( z==0 ) return;
     len = 0;
-    for(z2=z; *z2; len++){
-      SQLITE_SKIP_UTF8(z2);
+    if( p1<0 ){
+      for(z2=z; *z2; len++){
+        SQLITE_SKIP_UTF8(z2);
+      }
     }
   }
-  p1 = sqlite3_value_int(argv[1]);
   if( argc==3 ){
     p2 = sqlite3_value_int(argv[2]);
     if( p2<0 ){
@@ -220,10 +236,6 @@ static void substrFunc(
     }
   }
   assert( p1>=0 && p2>=0 );
-  if( p1+p2>len ){
-    p2 = len-p1;
-    if( p2<0 ) p2 = 0;
-  }
   if( p0type!=SQLITE_BLOB ){
     while( *z && p1 ){
       SQLITE_SKIP_UTF8(z);
@@ -234,6 +246,10 @@ static void substrFunc(
     }
     sqlite3_result_text(context, (char*)z, (int)(z2-z), SQLITE_TRANSIENT);
   }else{
+    if( p1+p2>len ){
+      p2 = len-p1;
+      if( p2<0 ) p2 = 0;
+    }
     sqlite3_result_blob(context, (char*)&z[p1], (int)p2, SQLITE_TRANSIENT);
   }
 }
@@ -255,14 +271,24 @@ static void roundFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
   }
   if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
   r = sqlite3_value_double(argv[0]);
-  zBuf = sqlite3_mprintf("%.*f",n,r);
-  if( zBuf==0 ){
-    sqlite3_result_error_nomem(context);
+  /* If Y==0 and X will fit in a 64-bit int,
+  ** handle the rounding directly,
+  ** otherwise use printf.
+  */
+  if( n==0 && r>=0 && r<LARGEST_INT64-1 ){
+    r = (double)((sqlite_int64)(r+0.5));
+  }else if( n==0 && r<0 && (-r)<LARGEST_INT64-1 ){
+    r = -(double)((sqlite_int64)((-r)+0.5));
   }else{
-    sqlite3AtoF(zBuf, &r);
+    zBuf = sqlite3_mprintf("%.*f",n,r);
+    if( zBuf==0 ){
+      sqlite3_result_error_nomem(context);
+      return;
+    }
+    sqlite3AtoF(zBuf, &r, sqlite3Strlen30(zBuf), SQLITE_UTF8);
     sqlite3_free(zBuf);
-    sqlite3_result_double(context, r);
   }
+  sqlite3_result_double(context, r);
 }
 #endif
 
@@ -335,6 +361,14 @@ static void lowerFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
   }
 }
 
+
+#if 0  /* This function is never used. */
+/*
+** The COALESCE() and IFNULL() functions used to be implemented as shown
+** here.  But now they are implemented as VDBE code so that unused arguments
+** do not have to be computed.  This legacy implementation is retained as
+** comment.
+*/
 /*
 ** Implementation of the IFNULL(), NVL(), and COALESCE() functions.  
 ** All three do the same thing.  They return the first non-NULL
@@ -353,6 +387,8 @@ static void ifnullFunc(
     }
   }
 }
+#endif /* NOT USED */
+#define ifnullFunc versionFunc   /* Substitute function - never called */
 
 /*
 ** Implementation of random().  Return a random integer.  
@@ -414,12 +450,18 @@ static void last_insert_rowid(
 ){
   sqlite3 *db = sqlite3_context_db_handle(context);
   UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  /* IMP: R-51513-12026 The last_insert_rowid() SQL function is a
+  ** wrapper around the sqlite3_last_insert_rowid() C/C++ interface
+  ** function. */
   sqlite3_result_int64(context, sqlite3_last_insert_rowid(db));
 }
 
 /*
-** Implementation of the changes() SQL function.  The return value is the
-** same as the sqlite3_changes() API function.
+** Implementation of the changes() SQL function.
+**
+** IMP: R-62073-11209 The changes() SQL function is a wrapper
+** around the sqlite3_changes() C/C++ function and hence follows the same
+** rules for counting changes.
 */
 static void changes(
   sqlite3_context *context,
@@ -442,6 +484,8 @@ static void total_changes(
 ){
   sqlite3 *db = sqlite3_context_db_handle(context);
   UNUSED_PARAMETER2(NotUsed, NotUsed2);
+  /* IMP: R-52756-41993 This function is a wrapper around the
+  ** sqlite3_total_changes() C/C++ interface. */
   sqlite3_result_int(context, sqlite3_total_changes(db));
 }
 
@@ -709,7 +753,9 @@ static void versionFunc(
   sqlite3_value **NotUsed2
 ){
   UNUSED_PARAMETER2(NotUsed, NotUsed2);
-  sqlite3_result_text(context, sqlite3_version, -1, SQLITE_STATIC);
+  /* IMP: R-48699-48617 This function is an SQL wrapper around the
+  ** sqlite3_libversion() C-interface. */
+  sqlite3_result_text(context, sqlite3_libversion(), -1, SQLITE_STATIC);
 }
 
 /*
@@ -723,9 +769,57 @@ static void sourceidFunc(
   sqlite3_value **NotUsed2
 ){
   UNUSED_PARAMETER2(NotUsed, NotUsed2);
-  sqlite3_result_text(context, SQLITE_SOURCE_ID, -1, SQLITE_STATIC);
+  /* IMP: R-24470-31136 This function is an SQL wrapper around the
+  ** sqlite3_sourceid() C interface. */
+  sqlite3_result_text(context, sqlite3_sourceid(), -1, SQLITE_STATIC);
 }
 
+/*
+** Implementation of the sqlite_compileoption_used() function.
+** The result is an integer that identifies if the compiler option
+** was used to build SQLite.
+*/
+#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
+static void compileoptionusedFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  const char *zOptName;
+  assert( argc==1 );
+  UNUSED_PARAMETER(argc);
+  /* IMP: R-39564-36305 The sqlite_compileoption_used() SQL
+  ** function is a wrapper around the sqlite3_compileoption_used() C/C++
+  ** function.
+  */
+  if( (zOptName = (const char*)sqlite3_value_text(argv[0]))!=0 ){
+    sqlite3_result_int(context, sqlite3_compileoption_used(zOptName));
+  }
+}
+#endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */
+
+/*
+** Implementation of the sqlite_compileoption_get() function. 
+** The result is a string that identifies the compiler options 
+** used to build SQLite.
+*/
+#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
+static void compileoptiongetFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  int n;
+  assert( argc==1 );
+  UNUSED_PARAMETER(argc);
+  /* IMP: R-04922-24076 The sqlite_compileoption_get() SQL function
+  ** is a wrapper around the sqlite3_compileoption_get() C/C++ function.
+  */
+  n = sqlite3_value_int(argv[0]);
+  sqlite3_result_text(context, sqlite3_compileoption_get(n), -1, SQLITE_STATIC);
+}
+#endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */
+
 /* Array for converting from half-bytes (nybbles) into ASCII hex
 ** digits. */
 static const char hexdigits[] = {
@@ -852,7 +946,7 @@ static void zeroblobFunc(
   if( n>db->aLimit[SQLITE_LIMIT_LENGTH] ){
     sqlite3_result_error_toobig(context);
   }else{
-    sqlite3_result_zeroblob(context, (int)n);
+    sqlite3_result_zeroblob(context, (int)n); /* IMP: R-00293-64994 */
   }
 }
 
@@ -919,14 +1013,14 @@ static void replaceFunc(
       testcase( nOut-2==db->aLimit[SQLITE_LIMIT_LENGTH] );
       if( nOut-1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
         sqlite3_result_error_toobig(context);
-        sqlite3DbFree(db, zOut);
+        sqlite3_free(zOut);
         return;
       }
       zOld = zOut;
       zOut = sqlite3_realloc(zOut, (int)nOut);
       if( zOut==0 ){
         sqlite3_result_error_nomem(context);
-        sqlite3DbFree(db, zOld);
+        sqlite3_free(zOld);
         return;
       }
       memcpy(&zOut[j], zRep, nRep);
@@ -1027,9 +1121,16 @@ static void trimFunc(
 }
 
 
+/* IMP: R-25361-16150 This function is omitted from SQLite by default. It
+** is only available if the SQLITE_SOUNDEX compile-time option is used
+** when SQLite is built.
+*/
 #ifdef SQLITE_SOUNDEX
 /*
 ** Compute the soundex encoding of a word.
+**
+** IMP: R-59782-00072 The soundex(X) function returns a string that is the
+** soundex encoding of the string X. 
 */
 static void soundexFunc(
   sqlite3_context *context,
@@ -1073,10 +1174,12 @@ static void soundexFunc(
     zResult[j] = 0;
     sqlite3_result_text(context, zResult, 4, SQLITE_TRANSIENT);
   }else{
+    /* IMP: R-64894-50321 The string "?000" is returned if the argument
+    ** is NULL or contains no ASCII alphabetic characters. */
     sqlite3_result_text(context, "?000", 4, SQLITE_STATIC);
   }
 }
-#endif
+#endif /* SQLITE_SOUNDEX */
 
 #ifndef SQLITE_OMIT_LOAD_EXTENSION
 /*
@@ -1136,13 +1239,8 @@ static void sumStep(sqlite3_context *context, int argc, sqlite3_value **argv){
     if( type==SQLITE_INTEGER ){
       i64 v = sqlite3_value_int64(argv[0]);
       p->rSum += v;
-      if( (p->approx|p->overflow)==0 ){
-        i64 iNewSum = p->iSum + v;
-        int s1 = (int)(p->iSum >> (sizeof(i64)*8-1));
-        int s2 = (int)(v       >> (sizeof(i64)*8-1));
-        int s3 = (int)(iNewSum >> (sizeof(i64)*8-1));
-        p->overflow = ((s1&s2&~s3) | (~s1&~s2&s3))?1:0;
-        p->iSum = iNewSum;
+      if( (p->approx|p->overflow)==0 && sqlite3AddInt64(&p->iSum, v) ){
+        p->overflow = 1;
       }
     }else{
       p->rSum += sqlite3_value_double(argv[0]);
@@ -1278,7 +1376,7 @@ static void groupConcatStep(
   if( pAccum ){
     sqlite3 *db = sqlite3_context_db_handle(context);
     int firstTerm = pAccum->useMalloc==0;
-    pAccum->useMalloc = 1;
+    pAccum->useMalloc = 2;
     pAccum->mxAlloc = db->aLimit[SQLITE_LIMIT_LENGTH];
     if( !firstTerm ){
       if( argc==2 ){
@@ -1311,20 +1409,15 @@ static void groupConcatFinalize(sqlite3_context *context){
 }
 
 /*
-** This function registered all of the above C functions as SQL
-** functions.  This should be the only routine in this file with
-** external linkage.
+** This routine does per-connection function registration.  Most
+** of the built-in functions above are part of the global function set.
+** This routine only deals with those that are not global.
 */
 void sqlite3RegisterBuiltinFunctions(sqlite3 *db){
-#ifndef SQLITE_OMIT_ALTERTABLE
-  sqlite3AlterFunctions(db);
-#endif
-  if( !db->mallocFailed ){
-    int rc = sqlite3_overload_function(db, "MATCH", 2);
-    assert( rc==SQLITE_NOMEM || rc==SQLITE_OK );
-    if( rc==SQLITE_NOMEM ){
-      db->mallocFailed = 1;
-    }
+  int rc = sqlite3_overload_function(db, "MATCH", 2);
+  assert( rc==SQLITE_NOMEM || rc==SQLITE_OK );
+  if( rc==SQLITE_NOMEM ){
+    db->mallocFailed = 1;
   }
 }
 
@@ -1352,10 +1445,10 @@ void sqlite3RegisterLikeFunctions(sqlite3 *db, int caseSensitive){
   }else{
     pInfo = (struct compareInfo*)&likeInfoNorm;
   }
-  sqlite3CreateFunc(db, "like", 2, SQLITE_ANY, pInfo, likeFunc, 0, 0);
-  sqlite3CreateFunc(db, "like", 3, SQLITE_ANY, pInfo, likeFunc, 0, 0);
-  sqlite3CreateFunc(db, "glob", 2, SQLITE_ANY, 
-      (struct compareInfo*)&globInfo, likeFunc, 0,0);
+  sqlite3CreateFunc(db, "like", 2, SQLITE_UTF8, pInfo, likeFunc, 0, 0, 0);
+  sqlite3CreateFunc(db, "like", 3, SQLITE_UTF8, pInfo, likeFunc, 0, 0, 0);
+  sqlite3CreateFunc(db, "glob", 2, SQLITE_UTF8, 
+      (struct compareInfo*)&globInfo, likeFunc, 0, 0, 0);
   setLikeOptFlag(db, "glob", SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE);
   setLikeOptFlag(db, "like", 
       caseSensitive ? (SQLITE_FUNC_LIKE | SQLITE_FUNC_CASE) : SQLITE_FUNC_LIKE);
@@ -1437,15 +1530,21 @@ void sqlite3RegisterGlobalFunctions(void){
     FUNCTION(upper,              1, 0, 0, upperFunc        ),
     FUNCTION(lower,              1, 0, 0, lowerFunc        ),
     FUNCTION(coalesce,           1, 0, 0, 0                ),
-    FUNCTION(coalesce,          -1, 0, 0, ifnullFunc       ),
     FUNCTION(coalesce,           0, 0, 0, 0                ),
+/*  FUNCTION(coalesce,          -1, 0, 0, ifnullFunc       ), */
+    {-1,SQLITE_UTF8,SQLITE_FUNC_COALESCE,0,0,ifnullFunc,0,0,"coalesce",0,0},
     FUNCTION(hex,                1, 0, 0, hexFunc          ),
-    FUNCTION(ifnull,             2, 0, 1, ifnullFunc       ),
+/*  FUNCTION(ifnull,             2, 0, 0, ifnullFunc       ), */
+    {2,SQLITE_UTF8,SQLITE_FUNC_COALESCE,0,0,ifnullFunc,0,0,"ifnull",0,0},
     FUNCTION(random,             0, 0, 0, randomFunc       ),
     FUNCTION(randomblob,         1, 0, 0, randomBlob       ),
     FUNCTION(nullif,             2, 0, 1, nullifFunc       ),
     FUNCTION(sqlite_version,     0, 0, 0, versionFunc      ),
     FUNCTION(sqlite_source_id,   0, 0, 0, sourceidFunc     ),
+#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
+    FUNCTION(sqlite_compileoption_used,1, 0, 0, compileoptionusedFunc  ),
+    FUNCTION(sqlite_compileoption_get, 1, 0, 0, compileoptiongetFunc  ),
+#endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */
     FUNCTION(quote,              1, 0, 0, quoteFunc        ),
     FUNCTION(last_insert_rowid,  0, 0, 0, last_insert_rowid),
     FUNCTION(changes,            0, 0, 0, changes          ),
@@ -1463,7 +1562,7 @@ void sqlite3RegisterGlobalFunctions(void){
     AGGREGATE(total,             1, 0, 0, sumStep,         totalFinalize    ),
     AGGREGATE(avg,               1, 0, 0, sumStep,         avgFinalize    ),
  /* AGGREGATE(count,             0, 0, 0, countStep,       countFinalize  ), */
-    {0,SQLITE_UTF8,SQLITE_FUNC_COUNT,0,0,0,countStep,countFinalize,"count",0},
+    {0,SQLITE_UTF8,SQLITE_FUNC_COUNT,0,0,0,countStep,countFinalize,"count",0,0},
     AGGREGATE(count,             1, 0, 0, countStep,       countFinalize  ),
     AGGREGATE(group_concat,      1, 0, 0, groupConcatStep, groupConcatFinalize),
     AGGREGATE(group_concat,      2, 0, 0, groupConcatStep, groupConcatFinalize),
@@ -1486,4 +1585,7 @@ void sqlite3RegisterGlobalFunctions(void){
     sqlite3FuncDefInsert(pHash, &aFunc[i]);
   }
   sqlite3RegisterDateTimeFunctions();
+#ifndef SQLITE_OMIT_ALTERTABLE
+  sqlite3AlterFunctions();
+#endif
 }