[sql] Import SQLite 3.17.0.

third_party/sqlite/src/tool/mkkeywordhash.c

 /*
 ** Compile and run this standalone program in order to generate code that
 ** implements a function that will translate alphabetic identifiers into
 ** parser token codes.
 */
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
 #include <assert.h>
 
@@ skipping 259 matching lines @@
   { "VIRTUAL",          "TK_VIRTUAL",      VTAB                   },
   { "WITH",             "TK_WITH",         CTE                    },
   { "WITHOUT",          "TK_WITHOUT",      ALWAYS                 },
   { "WHEN",             "TK_WHEN",         ALWAYS                 },
   { "WHERE",            "TK_WHERE",        ALWAYS                 },
 };
 
 /* Number of keywords */
 static int nKeyword = (sizeof(aKeywordTable)/sizeof(aKeywordTable[0]));
 
-/* Map all alphabetic characters into the same case */
+/* Map all alphabetic characters into lower-case for hashing.  This is
+** only valid for alphabetics.  In particular it does not work for '_'
+** and so the hash cannot be on a keyword position that might be an '_'.
+*/
 #define charMap(X)   (0x20|(X))
 
 /*
 ** Comparision function for two Keyword records
 */
 static int keywordCompare1(const void *a, const void *b){
   const Keyword *pA = (Keyword*)a;
   const Keyword *pB = (Keyword*)b;
   int n = pA->len - pB->len;
   if( n==0 ){
@@ skipping 267 matching lines @@
     if( j==0 ) printf("    ");
     printf("%s,%*s", zToken, (int)(14-strlen(zToken)), "");
     j++;
     if( j>=5 ){
       printf("\n");
       j = 0;
     }
   }
   printf("%s  };\n", j==0 ? "" : "\n");
 
-  printf("  int h, i;\n");
+  printf("  int i, j;\n");
+  printf("  const char *zKW;\n");
   printf("  if( n>=2 ){\n");
-  printf("    h = ((charMap(z[0])*4) ^ (charMap(z[n-1])*3) ^ n) %% %d;\n",
+  printf("    i = ((charMap(z[0])*4) ^ (charMap(z[n-1])*3) ^ n) %% %d;\n",
           bestSize);
-  printf("    for(i=((int)aHash[h])-1; i>=0; i=((int)aNext[i])-1){\n");
-  printf("      if( aLen[i]==n &&"
-                     " sqlite3StrNICmp(&zText[aOffset[i]],z,n)==0 ){\n");
+  printf("    for(i=((int)aHash[i])-1; i>=0; i=((int)aNext[i])-1){\n");
+  printf("      if( aLen[i]!=n ) continue;\n");
+  printf("      j = 0;\n");
+  printf("      zKW = &zText[aOffset[i]];\n");
+  printf("#ifdef SQLITE_ASCII\n");
+  printf("      while( j<n && (z[j]&~0x20)==zKW[j] ){ j++; }\n");
+  printf("#endif\n");
+  printf("#ifdef SQLITE_EBCDIC\n");
+  printf("      while( j<n && toupper(z[j])==zKW[j] ){ j++; }\n");
+  printf("#endif\n");
+  printf("      if( j<n ) continue;\n");
   for(i=0; i<nKeyword; i++){
-    printf("        testcase( i==%d ); /* %s */\n",
+    printf("      testcase( i==%d ); /* %s */\n",
            i, aKeywordTable[i].zOrigName);
   }
-  printf("        *pType = aCode[i];\n");
-  printf("        break;\n");
-  printf("      }\n");
+  printf("      *pType = aCode[i];\n");
+  printf("      break;\n");
   printf("    }\n");
   printf("  }\n");
   printf("  return n;\n");
   printf("}\n");
   printf("int sqlite3KeywordCode(const unsigned char *z, int n){\n");
   printf("  int id = TK_ID;\n");
   printf("  keywordCode((char*)z, n, &id);\n");
   printf("  return id;\n");
   printf("}\n");
   printf("#define SQLITE_N_KEYWORD %d\n", nKeyword);
 
   return 0;
 }