Bug#20404: SHOW CREATE TABLE fails with Turkish I

  
  Problem: SHOW CREATE TABLE printed garbage in table
  name for tables having TURKISH I
  (i.e. LATIN CAPITABLE LETTER I WITH DOT ABOVE)
  when lower-case-table-name=1.
  
  Reason: In some cases during lower/upper conversion in utf8,
  the result string can be shorter the original string
  (including the above letter). Old implementation of caseup_str()
  and casedn_str() didn't handle the result length properly,
  assuming that length cannot change.
  
  This fix changes the result type of cs->cset->casedn_str()
  and cs->cset->caseup_str() from VOID to UINT, to return
  the result length, as well as put '\0' terminator on a 
  proper place.
  
  Also, my_caseup_str_utf8() and my_casedn_str_utf8() were 
  rewritten not to use strlen() for performance purposes.
  It was done with help of adding of new functions - my_utf8_uni_no_range()
  and my_uni_utf8_no_range() - for null terminated strings.

include/m_ctype.h

@@ -178,8 +178,8 @@ typedef struct my_charset_handler_st
 	       unsigned char *s,unsigned char *e);
   
   /* Functions for case and sort convertion */
-  void    (*caseup_str)(struct charset_info_st *, char *);
-  void    (*casedn_str)(struct charset_info_st *, char *);
+  uint    (*caseup_str)(struct charset_info_st *, char *);
+  uint    (*casedn_str)(struct charset_info_st *, char *);
   uint    (*caseup)(struct charset_info_st *, char *src, uint srclen,
                                               char *dst, uint dstlen);
   uint    (*casedn)(struct charset_info_st *, char *src, uint srclen,
@@ -311,8 +311,8 @@ extern uint my_instr_simple(struct charset_info_st *,
 
 
 /* Functions for 8bit */
-extern void my_caseup_str_8bit(CHARSET_INFO *, char *);
-extern void my_casedn_str_8bit(CHARSET_INFO *, char *);
+extern uint my_caseup_str_8bit(CHARSET_INFO *, char *);
+extern uint my_casedn_str_8bit(CHARSET_INFO *, char *);
 extern uint my_caseup_8bit(CHARSET_INFO *, char *src, uint srclen,
                                            char *dst, uint dstlen);
 extern uint my_casedn_8bit(CHARSET_INFO *, char *src, uint srclen,
@@ -399,8 +399,8 @@ int my_mbcharlen_8bit(CHARSET_INFO *, uint c);
 
 
 /* Functions for multibyte charsets */
-extern void my_caseup_str_mb(CHARSET_INFO *, char *);
-extern void my_casedn_str_mb(CHARSET_INFO *, char *);
+extern uint my_caseup_str_mb(CHARSET_INFO *, char *);
+extern uint my_casedn_str_mb(CHARSET_INFO *, char *);
 extern uint my_caseup_mb(CHARSET_INFO *, char *src, uint srclen,
                                          char *dst, uint dstlen);
 extern uint my_casedn_mb(CHARSET_INFO *, char *src, uint srclen,

mysql-test/r/lowercase_table.result

@@ -84,3 +84,27 @@ create table t2 like T1;
 drop table t1, t2;
 show tables;
 Tables_in_test
+set names utf8;
+drop table if exists İ,İİ;
+create table İ (s1 int);
+show create table İ;
+Table	Create Table
+İ	CREATE TABLE `i` (
+  `s1` int(11) default NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+show tables;
+Tables_in_test
+i
+drop table İ;
+create table İİ (s1 int);
+show create table İİ;
+Table	Create Table
+İİ	CREATE TABLE `ii` (
+  `s1` int(11) default NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+show tables;
+Tables_in_test
+ii
+drop table İİ;
+set names latin1;
+End of 5.0 tests

mysql-test/t/lowercase_table.test

@@ -85,3 +85,23 @@ drop table t1, t2;
 show tables;
 
 # End of 4.1 tests
+
+
+#
+# Bug#20404: SHOW CREATE TABLE fails with Turkish I
+#
+set names utf8;
+--disable_warnings
+drop table if exists İ,İİ;
+--enable_warnings
+create table İ (s1 int);
+show create table İ;
+show tables;
+drop table İ;
+create table İİ (s1 int);
+show create table İİ;
+show tables;
+drop table İİ;
+set names latin1;
+
+--echo End of 5.0 tests

sql/sql_parse.cc

@@ -6177,7 +6177,7 @@ TABLE_LIST *st_select_lex::add_table_to_list(THD *thd,
 
   ptr->alias= alias_str;
   if (lower_case_table_names && table->table.length)
-    my_casedn_str(files_charset_info, table->table.str);
+    table->table.length= my_casedn_str(files_charset_info, table->table.str);
   ptr->table_name=table->table.str;
   ptr->table_name_length=table->table.length;
   ptr->lock_type=   lock_type;

strings/ctype-bin.c

@@ -211,9 +211,10 @@ static int my_strnncollsp_8bit_bin(CHARSET_INFO * cs __attribute__((unused)),
 
 /* This function is used for all conversion functions */
 
-static void my_case_str_bin(CHARSET_INFO *cs __attribute__((unused)),
+static uint my_case_str_bin(CHARSET_INFO *cs __attribute__((unused)),
 			    char *str __attribute__((unused)))
 {
+  return 0;
 }
 
 static uint my_case_bin(CHARSET_INFO *cs __attribute__((unused)),

strings/ctype-mb.c

@@ -21,40 +21,44 @@
 #ifdef USE_MB
 
 
-void my_caseup_str_mb(CHARSET_INFO * cs, char *str)
+uint my_caseup_str_mb(CHARSET_INFO * cs, char *str)
 {
   register uint32 l;
-  register uchar *map=cs->to_upper;
+  register uchar *map= cs->to_upper;
+  char *str_orig= str;
   
   while (*str)
   {
     /* Pointing after the '\0' is safe here. */
-    if ((l=my_ismbchar(cs, str, str + cs->mbmaxlen)))
-      str+=l;
+    if ((l= my_ismbchar(cs, str, str + cs->mbmaxlen)))
+      str+= l;
     else
     { 
-      *str=(char) map[(uchar)*str];
+      *str= (char) map[(uchar)*str];
       str++;
     }
   }
+  return str - str_orig;
 }
 
-void my_casedn_str_mb(CHARSET_INFO * cs, char *str)
+uint my_casedn_str_mb(CHARSET_INFO * cs, char *str)
 {
   register uint32 l;
-  register uchar *map=cs->to_lower;
+  register uchar *map= cs->to_lower;
+  char *str_orig= str;
   
   while (*str)
   {
     /* Pointing after the '\0' is safe here. */
-    if ((l=my_ismbchar(cs, str, str + cs->mbmaxlen)))
-      str+=l;
+    if ((l= my_ismbchar(cs, str, str + cs->mbmaxlen)))
+      str+= l;
     else
     {
-      *str=(char) map[(uchar)*str];
+      *str= (char) map[(uchar)*str];
       str++;
     }
   }
+  return str - str_orig;
 }
 
 uint my_caseup_mb(CHARSET_INFO * cs, char *src, uint srclen,

strings/ctype-simple.c

@@ -188,20 +188,26 @@ int my_strnncollsp_simple(CHARSET_INFO * cs, const uchar *a, uint a_length,
 }
 
 
-void my_caseup_str_8bit(CHARSET_INFO * cs,char *str)
+uint my_caseup_str_8bit(CHARSET_INFO * cs,char *str)
 {
-  register uchar *map=cs->to_upper;
-  while ((*str = (char) map[(uchar) *str]) != 0)
+  register uchar *map= cs->to_upper;
+  char *str_orig= str;
+  while ((*str= (char) map[(uchar) *str]) != 0)
     str++;
+  return str - str_orig;
 }
 
-void my_casedn_str_8bit(CHARSET_INFO * cs,char *str)
+
+uint my_casedn_str_8bit(CHARSET_INFO * cs,char *str)
 {
-  register uchar *map=cs->to_lower;
-  while ((*str = (char) map[(uchar)*str]) != 0)
+  register uchar *map= cs->to_lower;
+  char *str_orig= str;
+  while ((*str= (char) map[(uchar) *str]) != 0)
     str++;
+  return str - str_orig;
 }
 
+
 uint my_caseup_8bit(CHARSET_INFO * cs, char *src, uint srclen,
                     char *dst __attribute__((unused)),
                     uint dstlen __attribute__((unused)))

strings/ctype-ucs2.c

@@ -159,13 +159,13 @@ static void my_hash_sort_ucs2(CHARSET_INFO *cs, const uchar *s, uint slen,
 }
 
 
-static void my_caseup_str_ucs2(CHARSET_INFO * cs  __attribute__((unused)), 
+static uint my_caseup_str_ucs2(CHARSET_INFO * cs  __attribute__((unused)), 
 			       char * s __attribute__((unused)))
 {
+  return 0;
 }
 
 
-
 static uint my_casedn_ucs2(CHARSET_INFO *cs, char *src, uint srclen,
                            char *dst __attribute__((unused)),
                            uint dstlen __attribute__((unused)))
@@ -188,9 +188,11 @@ static uint my_casedn_ucs2(CHARSET_INFO *cs, char *src, uint srclen,
   return srclen;
 }
 
-static void my_casedn_str_ucs2(CHARSET_INFO *cs __attribute__((unused)), 
+
+static uint my_casedn_str_ucs2(CHARSET_INFO *cs __attribute__((unused)), 
 			       char * s __attribute__((unused)))
 {
+  return 0;
 }
 
 

strings/ctype-utf8.c

@@ -2045,6 +2045,52 @@ static int my_utf8_uni(CHARSET_INFO *cs __attribute__((unused)),
   return MY_CS_ILSEQ;
 }
 
+
+/*
+  The same as above, but without range check
+  for example, for a null-terminated string
+*/
+static int my_utf8_uni_no_range(CHARSET_INFO *cs __attribute__((unused)),
+                                my_wc_t * pwc, const uchar *s)
+{
+  unsigned char c;
+
+  c= s[0];
+  if (c < 0x80)
+  {
+    *pwc = c;
+    return 1;
+  }
+
+  if (c < 0xc2)
+    return MY_CS_ILSEQ;
+
+  if (c < 0xe0)
+  {
+    if (!((s[1] ^ 0x80) < 0x40))
+      return MY_CS_ILSEQ;
+
+    *pwc = ((my_wc_t) (c & 0x1f) << 6) | (my_wc_t) (s[1] ^ 0x80);
+    return 2;
+  }
+  
+  if (c < 0xf0)
+  {
+    if (!((s[1] ^ 0x80) < 0x40 &&
+          (s[2] ^ 0x80) < 0x40 &&
+          (c >= 0xe1 || s[1] >= 0xa0)))
+      return MY_CS_ILSEQ;
+
+    *pwc= ((my_wc_t) (c & 0x0f) << 12)   |
+          ((my_wc_t) (s[1] ^ 0x80) << 6) |
+           (my_wc_t) (s[2] ^ 0x80);
+
+    return 3;
+  }
+  return MY_CS_ILSEQ;
+}
+
+
 static int my_uni_utf8 (CHARSET_INFO *cs __attribute__((unused)) ,
                  my_wc_t wc, uchar *r, uchar *e)
 {
@@ -2091,6 +2137,34 @@ static int my_uni_utf8 (CHARSET_INFO *cs __attribute__((unused)) ,
 }
 
 
+/*
+  The same as above, but without range check.
+*/
+static int my_uni_utf8_no_range(CHARSET_INFO *cs __attribute__((unused)),
+                                my_wc_t wc, uchar *r)
+{
+  int count;
+
+  if (wc < 0x80)
+    count= 1;
+  else if (wc < 0x800)
+    count= 2;
+  else if (wc < 0x10000)
+    count= 3;
+  else
+    return MY_CS_ILUNI;
+
+  switch (count)
+  {
+    /* Fall through all cases!!! */
+    case 3: r[2]= (uchar) (0x80 | (wc & 0x3f)); wc= wc >> 6; wc |= 0x800;
+    case 2: r[1]= (uchar) (0x80 | (wc & 0x3f)); wc= wc >> 6; wc |= 0xc0;
+    case 1: r[0]= (uchar) wc;
+  }
+  return count;
+}
+
+
 static uint my_caseup_utf8(CHARSET_INFO *cs, char *src, uint srclen,
                                              char *dst, uint dstlen)
 {
@@ -2141,10 +2215,26 @@ static void my_hash_sort_utf8(CHARSET_INFO *cs, const uchar *s, uint slen,
 }
 
 
-static void my_caseup_str_utf8(CHARSET_INFO * cs, char * s)
+static uint my_caseup_str_utf8(CHARSET_INFO *cs, char *src)
 {
-  uint len= (uint) strlen(s);
-  my_caseup_utf8(cs, s, len, s, len);
+  my_wc_t wc;
+  int srcres, dstres;
+  char *dst= src, *dst0= src;
+  MY_UNICASE_INFO **uni_plane= cs->caseinfo;
+  DBUG_ASSERT(cs->caseup_multiply == 1);
+
+  while (*src &&
+         (srcres= my_utf8_uni_no_range(cs, &wc, (uchar *) src)) > 0)
+  {
+    int plane= (wc>>8) & 0xFF;
+    wc= uni_plane[plane] ? uni_plane[plane][wc & 0xFF].toupper : wc;
+    if ((dstres= my_uni_utf8_no_range(cs, wc, (uchar*) dst)) <= 0)
+      break;
+    src+= srcres;
+    dst+= dstres;
+  }
+  *dst= '\0';
+  return (uint) (dst - dst0);
 }
 
 
@@ -2170,10 +2260,43 @@ static uint my_casedn_utf8(CHARSET_INFO *cs, char *src, uint srclen,
   return (uint) (dst - dst0);
 }
 
-static void my_casedn_str_utf8(CHARSET_INFO *cs, char * s)
+
+static uint my_casedn_str_utf8(CHARSET_INFO *cs, char *src)
 {
-  uint len= (uint) strlen(s);
-  my_casedn_utf8(cs, s, len, s, len);
+  my_wc_t wc;
+  int srcres, dstres;
+  char *dst= src, *dst0= src;
+  MY_UNICASE_INFO **uni_plane= cs->caseinfo;
+  DBUG_ASSERT(cs->casedn_multiply == 1);
+
+  while (*src &&
+         (srcres= my_utf8_uni_no_range(cs, &wc, (uchar *) src)) > 0)
+  {
+    int plane= (wc>>8) & 0xFF;
+    wc= uni_plane[plane] ? uni_plane[plane][wc & 0xFF].tolower : wc;
+    if ((dstres= my_uni_utf8_no_range(cs, wc, (uchar*) dst)) <= 0)
+      break;
+    src+= srcres;
+    dst+= dstres;
+  }
+
+  /*
+   In rare cases lower string can be shorter than
+   the original string, for example:
+
+   "U+0130 LATIN CAPITAL LETTER I WITH DOT ABOVE"
+   (which is 0xC4B0 in utf8, i.e. two bytes)
+
+   is converted into
+
+   "U+0069 LATIN SMALL LETTER I"
+   (which is 0x69 in utf8, i.e. one byte)
+
+   So, we need to put '\0' terminator after converting.
+  */
+
+  *dst= '\0';
+  return (uint) (dst - dst0);
 }