Slightly smaller and faster LIKE/GLOB comparison implementation.

FossilOrigin-Name: 5dddcc78eec5bcd0c7e8fe1b70875ce775488f0c

manifest

@@ -1,5 +1,5 @@
-C Typo\sfix\sin\sthe\sprevious\scommit.
-D 2016-01-08T22:31:00.176
+C Slightly\ssmaller\sand\sfaster\sLIKE/GLOB\scomparison\simplementation.
+D 2016-01-11T03:48:18.694
 F Makefile.in 7c8cc4c2f0179efc6fa9492141d1fb65f4807054
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc e45d8b9b56dfa3f2cd860b2c28bd9d304513b042
@@ -289,7 +289,7 @@ F src/delete.c 00af9f08a15ddc5cba5962d3d3e5bf2d67b2e7da
 F src/expr.c fe55c489362d1429c364e98c877514f4455f45a6
 F src/fault.c 160a0c015b6c2629d3899ed2daf63d75754a32bb
 F src/fkey.c e18b3dff7d47c7bcac5ac4fc178a89b9fd322b44
-F src/func.c cf5e10af9125b245f1b962e8ba4d520a37818795
+F src/func.c ccaf46fa98f795673afbfab73dff7c18db88f3cd
 F src/global.c bd5a0af3f30b0c01be6db756c626cd3c33a3d260
 F src/hash.c 4263fbc955f26c2e8cdc0cf214bc42435aa4e4f5
 F src/hash.h c8f3c31722cf3277d03713909761e152a5b81094
@@ -1406,7 +1406,7 @@ F tool/vdbe_profile.tcl 246d0da094856d72d2c12efec03250d71639d19f
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 48bd54594752d5be3337f12c72f28d2080cb630b
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 122c111e360761de8166e16ca151cb7260ee9bf8
-R 459dbc63e3c56e9f1bc36ac4dabf3593
+P 52c166039831cc8423e2252019ef64a21b9d7c2a
+R b3c3f3b7322fc6b535d7f3bde12a066b
 U drh
-Z 6b54e5c713520cd21bd942bd06142b38
+Z 4530f1ebb856a62f721161bd7860507a

manifest.uuid

@@ -1 +1 @@
-52c166039831cc8423e2252019ef64a21b9d7c2a
+5dddcc78eec5bcd0c7e8fe1b70875ce775488f0c

src/func.c

@@ -567,10 +567,10 @@ static void total_changes(
 ** A structure defining how to do GLOB-style comparisons.
 */
 struct compareInfo {
-  u8 matchAll;
-  u8 matchOne;
-  u8 matchSet;
-  u8 noCase;
+  u8 matchAll;          /* "*" or "%" */
+  u8 matchOne;          /* "?" or "_" */
+  u8 matchSet;          /* "[" or 0 */
+  u8 noCase;            /* true to ignore case differences */
 };
 
 /*
@@ -633,22 +633,14 @@ static int patternCompare(
   const u8 *zPattern,              /* The glob pattern */
   const u8 *zString,               /* The string to compare against the glob */
   const struct compareInfo *pInfo, /* Information about how to do the compare */
-  u32 esc                          /* The escape character */
+  u32 matchOther                   /* The escape char (LIKE) or '[' (GLOB) */
 ){
   u32 c, c2;                       /* Next pattern and input string chars */
   u32 matchOne = pInfo->matchOne;  /* "?" or "_" */
   u32 matchAll = pInfo->matchAll;  /* "*" or "%" */
-  u32 matchOther;                  /* "[" or the escape character */
   u8 noCase = pInfo->noCase;       /* True if uppercase==lowercase */
   const u8 *zEscaped = 0;          /* One past the last escaped input char */
   
-  /* The GLOB operator does not have an ESCAPE clause.  And LIKE does not
-  ** have the matchSet operator.  So we either have to look for one or
-  ** the other, never both.  Hence the single variable matchOther is used
-  ** to store the one we have to look for.
-  */
-  matchOther = esc ? esc : pInfo->matchSet;
-
   while( (c = Utf8Read(zPattern))!=0 ){
     if( c==matchAll ){  /* Match "*" */
       /* Skip over multiple "*" characters in the pattern.  If there
@@ -662,7 +654,7 @@ static int patternCompare(
       if( c==0 ){
         return 1;   /* "*" at the end of the pattern matches */
       }else if( c==matchOther ){
-        if( esc ){
+        if( pInfo->matchSet==0 ){
           c = sqlite3Utf8Read(&zPattern);
           if( c==0 ) return 0;
         }else{
@@ -670,7 +662,7 @@ static int patternCompare(
           ** recursive search in this case, but it is an unusual case. */
           assert( matchOther<0x80 );  /* '[' is a single-byte character */
           while( *zString
-                 && patternCompare(&zPattern[-1],zString,pInfo,esc)==0 ){
+                 && patternCompare(&zPattern[-1],zString,pInfo,matchOther)==0 ){
             SQLITE_SKIP_UTF8(zString);
           }
           return *zString!=0;
@@ -696,18 +688,18 @@ static int patternCompare(
         }
         while( (c2 = *(zString++))!=0 ){
           if( c2!=c && c2!=cx ) continue;
-          if( patternCompare(zPattern,zString,pInfo,esc) ) return 1;
+          if( patternCompare(zPattern,zString,pInfo,matchOther) ) return 1;
         }
       }else{
         while( (c2 = Utf8Read(zString))!=0 ){
           if( c2!=c ) continue;
-          if( patternCompare(zPattern,zString,pInfo,esc) ) return 1;
+          if( patternCompare(zPattern,zString,pInfo,matchOther) ) return 1;
         }
       }
       return 0;
     }
     if( c==matchOther ){
-      if( esc ){
+      if( pInfo->matchSet==0 ){
         c = sqlite3Utf8Read(&zPattern);
         if( c==0 ) return 0;
         zEscaped = zPattern;
@@ -760,7 +752,7 @@ static int patternCompare(
 ** The sqlite3_strglob() interface.
 */
 int sqlite3_strglob(const char *zGlobPattern, const char *zString){
-  return patternCompare((u8*)zGlobPattern, (u8*)zString, &globInfo, 0)==0;
+  return patternCompare((u8*)zGlobPattern, (u8*)zString, &globInfo, '[')==0;
 }
 
 /*
@@ -798,9 +790,10 @@ static void likeFunc(
   sqlite3_value **argv
 ){
   const unsigned char *zA, *zB;
-  u32 escape = 0;
+  u32 escape;
   int nPat;
   sqlite3 *db = sqlite3_context_db_handle(context);
+  struct compareInfo *pInfo = sqlite3_user_data(context);
 
 #ifdef SQLITE_LIKE_DOESNT_MATCH_BLOBS
   if( sqlite3_value_type(argv[0])==SQLITE_BLOB
@@ -840,13 +833,13 @@ static void likeFunc(
       return;
     }
     escape = sqlite3Utf8Read(&zEsc);
+  }else{
+    escape = pInfo->matchSet;
   }
   if( zA && zB ){
-    struct compareInfo *pInfo = sqlite3_user_data(context);
 #ifdef SQLITE_TEST
     sqlite3_like_count++;
 #endif
-    
     sqlite3_result_int(context, patternCompare(zB, zA, pInfo, escape));
   }
 }