my_strnncoll_latin1_de rewritten from scratch. Bug with overlapping combos went away.

mysql-test/r/ctype_latin1_de.result

@@ -196,6 +196,9 @@ strcmp('
 select strcmp('u','a'),strcmp('u','');
 strcmp('u','a')	strcmp('u','')
 1	1
+select strcmp('s', 'a'), strcmp('a', 'x');
+strcmp('s', 'a')	strcmp('a', 'x')
+-1	-1
 create table t1 (a varchar(10), key(a), fulltext (a));
 insert into t1 values ("a"),("abc"),("abcd"),("hello"),("test");
 select * from t1 where a like "abc%";

mysql-test/t/ctype_latin1_de.test

@@ -34,6 +34,10 @@ select strcmp('af','
 select strcmp('a','ss'),strcmp('ssa',''),strcmp('sssb','sa'),strcmp('','s');
 select strcmp('u','a'),strcmp('u','');
 
+#
+# overlapping combo's
+#
+select strcmp('s', 'a'), strcmp('a', 'x');
 #
 # Some other simple tests with the current character set
 #

strings/ctype-latin1_de.c

@@ -102,6 +102,7 @@ uchar to_upper_latin1_de[] = {
  * Ü, ü, Ö, ö, Ä, ä
  */
 
+/* QQ: why it is necessary ? */
 uchar sort_order_latin1_de[] = {
     0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
    16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
@@ -121,6 +122,41 @@ uchar sort_order_latin1_de[] = {
    68, 78, 79, 79, 79, 79,214,247,216, 85, 85, 85,220, 89,222, 89
 };
 
+
+/* same as sort_order_latin_de, but maps ALL accented chars to unacented ones */
+uchar combo1map[]={
+    0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
+   16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+   32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
+   48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
+   64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
+   80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
+   96, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
+   80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,123,124,125,126,127,
+  128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,
+  144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,
+  160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,
+  176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,
+   65, 65, 65, 65, 65, 65, 92, 67, 69, 69, 69, 69, 73, 73, 73, 73,
+   68, 78, 79, 79, 79, 79, 79,215,216, 85, 85, 85, 85, 89,222, 83,
+   65, 65, 65, 65, 65, 65, 92, 67, 69, 69, 69, 69, 73, 73, 73, 73,
+   68, 78, 79, 79, 79, 79, 79,247,216, 85, 85, 85, 85, 89,222, 89
+};
+
+uchar combo2map[]={
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,69, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0,69, 0, 0, 0, 0, 0,69, 0, 0,83, 0, 0, 0, 0,69, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,69, 0, 0, 0, 0, 0,69, 0, 0, 0, 0
+};
+
+/* no longer needed
 #define L1_AE 196
 #define L1_ae 228
 #define L1_OE 214
@@ -128,7 +164,7 @@ uchar sort_order_latin1_de[] = {
 #define L1_UE 220
 #define L1_ue 252
 #define L1_ss 223
-
+*/
 
 /*
   Some notes about the following comparison rules:
@@ -143,95 +179,23 @@ uchar sort_order_latin1_de[] = {
   sort_order_latin_de[] at all
 */
 
-
-#define CHECK_S1_COMBO(ch1, ch2, str1, str1_end, res_if_str1_smaller, str2, fst, snd, accent)   \
-  /* Invariant: ch1 == fst == sort_order_latin1_de[accent] && ch1 != ch2 */ \
-  if (ch2 != accent)							\
-  {									\
-    ch1= fst;								\
-    goto normal;							\
-  }									\
-  if (str1 == str1_end)							\
-    return res_if_str1_smaller;						\
-  {									\
-     int diff = (int) sort_order_latin1_de[*str1] - snd;		\
-     if (diff)								\
-        return diff*(-(res_if_str1_smaller));				\
-      /* They are equal (e.g., "Ae" == 'ä') */				\
-     str1++;								\
-  }
-
-
 int my_strnncoll_latin1_de(const uchar * s1, int len1,
                            const uchar * s2, int len2)
 {
   const uchar *e1 = s1 + len1;
   const uchar *e2 = s2 + len2;
+  uchar c1, c12=0, c2, c22=0;
 
-  while (s1 < e1 && s2 < e2)
+  while ((s1 < e1 || c12) && (s2 < e2 || c22))
   {
-    /*
-      Because sort_order_latin1_de doesn't convert 'Ä', Ü or ß we
-      can use it here.
-    */
-    uchar c1 = sort_order_latin1_de[*s1++];
-    uchar c2 = sort_order_latin1_de[*s2++];
-    if (c1 != c2)
-    {
-      switch (c1) {
-      case 'A':
-	CHECK_S1_COMBO(c1, c2, s1, e1, -1, s2, 'A', 'E', L1_AE);
-	break;
-      case 'O':
-	CHECK_S1_COMBO(c1, c2, s1, e1, -1, s2, 'O', 'E', L1_OE);
-	break;
-      case 'U':
-	CHECK_S1_COMBO(c1, c2, s1, e1, -1, s2, 'U', 'E', L1_UE);
-	break;
-      case 'S':
-	CHECK_S1_COMBO(c1, c2, s1, e1, -1, s2, 'S', 'S', L1_ss);
-	break;
-      case L1_AE:
-	CHECK_S1_COMBO(c1, c2, s2, e2, 1, s1, 'A', 'E', 'A');
-	break;
-      case L1_OE:
-	CHECK_S1_COMBO(c1, c2, s2, e2, 1, s1, 'O', 'E', 'O');
-	break;
-      case L1_UE:
-	CHECK_S1_COMBO(c1, c2, s2, e2, 1, s1, 'U', 'E', 'U');
-	break;
-      case L1_ss:
-	CHECK_S1_COMBO(c1, c2, s2, e2, 1, s1, 'S', 'S', 'S');
-	break;
-      default:
-	/*
-	  Handle the case where 'c2' is a special character
-	  If this is true, we know that c1 can't match this character.
-	*/
-    normal:
-	switch (c2) {
-	case L1_AE:
-	  return  (int) c1 - (int) 'A';
-	case L1_OE:
-	  return  (int) c1 - (int) 'O';
-	case L1_UE:
-	  return  (int) c1 - (int) 'U';
-	case L1_ss:
-	  return  (int) c1 - (int) 'S';
-	default:
-	{
-	  int diff= (int) c1 - (int) c2;
-	  if (diff)
-	    return diff;
-	}
-	break;
-	}
-      }
-    }
+    if (c12) { c1=c12; c12=0; } else { c12=combo2map[*s1]; c1=combo1map[*s1++]; }
+    if (c22) { c2=c22; c22=0; } else { c22=combo2map[*s2]; c2=combo1map[*s2++]; }
+    if (c1 != c2) return (int)c1 - (int)c2;
   }
+
   /* A simple test of string lengths won't work -- we test to see
    * which string ran out first */
-  return s1 < e1 ? 1 : s2 < e2 ? -1 : 0;
+  return (s1 < e1 || c12)? 1 : (s2 < e2 || c22)? -1 : 0;
 }
 
 
@@ -240,35 +204,12 @@ int my_strnxfrm_latin1_de(uchar * dest, const uchar * src, int len, int srclen)
   const uchar *dest_orig = dest;
   const uchar *de = dest + len;
   const uchar *se = src + srclen;
-  while (src < se && dest < de)
+  for ( ; src < se && dest < de ; src++)
   {
-    uchar chr=sort_order_latin1_de[*src];
-    switch (chr) {
-    case L1_AE:
-      *dest++ = 'A';
-      if (dest < de)
-	*dest++ = 'E';
-      break;
-    case L1_OE:
-      *dest++ = 'O';
-      if (dest < de)
-	*dest++ = 'E';
-      break;
-    case L1_UE:
-      *dest++ = 'U';
-      if (dest < de)
-	*dest++ = 'E';
-      break;
-    case L1_ss:
-      *dest++ = 'S';
-      if (dest < de)
-	*dest++ = 'S';
-      break;
-    default:
-      *dest++= chr;
-      break;
-    }
-    ++src;
+    uchar chr=combo1map[*src];
+    *dest++=chr;
+    if ((chr=combo2map[*src]) && dest < de)
+      *dest++=chr;
   }
   return dest - dest_orig;
 }