Merge with MariaDB 5.2

1 files changed, 91 insertions, 37 deletions

diff --git a/sql/item_strfunc.cc b/sql/item_strfunc.cc
index 39776643ddd..148170110f5 100644
--- a/sql/item_strfunc.cc
+++ b/sql/item_strfunc.cc
@@ -39,6 +39,9 @@ C_MODE_START
 #include "../mysys/my_static.h"			// For soundex_map
 C_MODE_END
 
+/**
+   @todo Remove this. It is not safe to use a shared String object.
+ */
 String my_empty_string("",default_charset_info);
 
 
@@ -116,7 +119,6 @@ String *Item_func_md5::val_str(String *str)
 {
   DBUG_ASSERT(fixed == 1);
   String * sptr= args[0]->val_str(str);
-  str->set_charset(&my_charset_bin);
   if (sptr)
   {
     uchar digest[16];
@@ -129,6 +131,7 @@ String *Item_func_md5::val_str(String *str)
       return 0;
     }
     array_to_hex((char *) str->ptr(), (const char*) digest, 16);
+    str->set_charset(&my_charset_bin);
     str->length((uint) 32);
     return str;
   }
@@ -155,7 +158,6 @@ String *Item_func_sha::val_str(String *str)
 {
   DBUG_ASSERT(fixed == 1);
   String * sptr= args[0]->val_str(str);
-  str->set_charset(&my_charset_bin);
   if (sptr)  /* If we got value different from NULL */
   {
     SHA1_CONTEXT context;  /* Context used to generate SHA1 hash */
@@ -165,11 +167,13 @@ String *Item_func_sha::val_str(String *str)
     /* No need to check error as the only case would be too long message */
     mysql_sha1_input(&context,
                      (const uchar *) sptr->ptr(), sptr->length());
+
     /* Ensure that memory is free and we got result */
     if (!( str->alloc(SHA1_HASH_SIZE*2) ||
            (mysql_sha1_result(&context,digest))))
     {
       array_to_hex((char *) str->ptr(), (const char*) digest, SHA1_HASH_SIZE);
+      str->set_charset(&my_charset_bin);
       str->length((uint)  SHA1_HASH_SIZE*2);
       null_value=0;
       return str;
@@ -461,7 +465,7 @@ String *Item_func_des_encrypt::val_str(String *str)
   if ((null_value= args[0]->null_value))
     return 0;                                   // ENCRYPT(NULL) == NULL
   if ((res_length=res->length()) == 0)
-    return &my_empty_string;
+    return make_empty_result();
 
   if (arg_count == 1)
   {
@@ -517,6 +521,7 @@ String *Item_func_des_encrypt::val_str(String *str)
   tmp_arg[res_length-1]=tail;                   // save extra length
   tmp_value.realloc(res_length+1);
   tmp_value.length(res_length+1);
+  tmp_value.set_charset(&my_charset_bin);
   tmp_value[0]=(char) (128 | key_number);
   // Real encryption
   bzero((char*) &ivec,sizeof(ivec));
@@ -604,6 +609,7 @@ String *Item_func_des_decrypt::val_str(String *str)
   if ((tail=(uint) (uchar) tmp_value[length-2]) > 8)
     goto wrong_key;				     // Wrong key
   tmp_value.length(length-1-tail);
+  tmp_value.set_charset(&my_charset_bin);
   return &tmp_value;
 
 error:
@@ -641,7 +647,7 @@ String *Item_func_concat_ws::val_str(String *str)
 
   use_as_buff= &tmp_value;
   str->length(0);				// QQ; Should be removed
-  res=str;
+  res=str;                                      // If 0 arg_count
 
   // Skip until non-null argument is found.
   // If not, return the empty string
@@ -653,7 +659,7 @@ String *Item_func_concat_ws::val_str(String *str)
     }
 
   if (i ==  arg_count)
-    return &my_empty_string;
+    return make_empty_result();
 
   for (i++; i < arg_count ; i++)
   {
@@ -804,7 +810,7 @@ String *Item_func_reverse::val_str(String *str)
     return 0;
   /* An empty string is a special case as the string pointer may be null */
   if (!res->length())
-    return &my_empty_string;
+    return make_empty_result();
   if (tmp_value.alloced_length() < res->length() &&
       tmp_value.realloc(res->length()))
   {
@@ -1144,8 +1150,7 @@ String *Item_func_left::val_str(String *str)
 
   /* if "unsigned_flag" is set, we have a *huge* positive number. */
   if ((length <= 0) && (!args[1]->unsigned_flag))
-    return &my_empty_string;
-
+    return make_empty_result();
   if ((res->length() <= (ulonglong) length) ||
       (res->length() <= (char_pos= res->charpos((int) length))))
     return res;
@@ -1188,7 +1193,7 @@ String *Item_func_right::val_str(String *str)
 
   /* if "unsigned_flag" is set, we have a *huge* positive number. */
   if ((length <= 0) && (!args[1]->unsigned_flag))
-    return &my_empty_string; /* purecov: inspected */
+    return make_empty_result(); /* purecov: inspected */
 
   if (res->length() <= (ulonglong) length)
     return res; /* purecov: inspected */
@@ -1227,7 +1232,7 @@ String *Item_func_substr::val_str(String *str)
   /* Negative or zero length, will return empty string. */
   if ((arg_count == 3) && (length <= 0) && 
       (length == 0 || !args[2]->unsigned_flag))
-    return &my_empty_string;
+    return make_empty_result();
 
   /* Assumes that the maximum length of a String is < INT_MAX32. */
   /* Set here so that rest of code sees out-of-bound value as such. */
@@ -1238,12 +1243,12 @@ String *Item_func_substr::val_str(String *str)
   /* Assumes that the maximum length of a String is < INT_MAX32. */
   if ((!args[1]->unsigned_flag && (start < INT_MIN32 || start > INT_MAX32)) ||
       (args[1]->unsigned_flag && ((ulonglong) start > INT_MAX32)))
-    return &my_empty_string;
+    return make_empty_result();
 
   start= ((start < 0) ? res->numchars() + start : start - 1);
   start= res->charpos((int) start);
   if ((start < 0) || ((uint) start + 1 > res->length()))
-    return &my_empty_string;
+    return make_empty_result();
 
   length= res->charpos((int) length, (uint32) start);
   tmp_length= res->length() - start;
@@ -1306,7 +1311,7 @@ String *Item_func_substr_index::val_str(String *str)
   null_value=0;
   uint delimiter_length= delimiter->length();
   if (!res->length() || !delimiter_length || !count)
-    return &my_empty_string;		// Wrong parameters
+    return make_empty_result();		// Wrong parameters
 
   res->set_charset(collation.collation);
 
@@ -1655,7 +1660,7 @@ String *Item_func_password::val_str(String *str)
   if ((null_value=args[0]->null_value))
     return 0;
   if (res->length() == 0)
-    return &my_empty_string;
+    return make_empty_result();
   my_make_scrambled_password(tmp_value, res->ptr(), res->length());
   str->set(tmp_value, SCRAMBLED_PASSWORD_CHAR_LENGTH, res->charset());
   return str;
@@ -1679,7 +1684,7 @@ String *Item_func_old_password::val_str(String *str)
   if ((null_value=args[0]->null_value))
     return 0;
   if (res->length() == 0)
-    return &my_empty_string;
+    return make_empty_result();
   my_make_scrambled_password_323(tmp_value, res->ptr(), res->length());
   str->set(tmp_value, SCRAMBLED_PASSWORD_CHAR_LENGTH_323, res->charset());
   return str;
@@ -1707,8 +1712,7 @@ String *Item_func_encrypt::val_str(String *str)
   if ((null_value=args[0]->null_value))
     return 0;
   if (res->length() == 0)
-    return &my_empty_string;
-
+    return make_empty_result();
   if (arg_count == 1)
   {					// generate random salt
     time_t timestamp=current_thd->query_start();
@@ -1968,7 +1972,7 @@ String *Item_func_soundex::val_str(String *str)
   for ( ; ; ) /* Skip pre-space */
   {
     if ((rc= cs->cset->mb_wc(cs, &wc, (uchar*) from, (uchar*) end)) <= 0)
-      return &my_empty_string; /* EOL or invalid byte sequence */
+      return make_empty_result(); /* EOL or invalid byte sequence */
     
     if (rc == 1 && cs->ctype)
     {
@@ -1993,7 +1997,7 @@ String *Item_func_soundex::val_str(String *str)
         {
           /* Extra safety - should not really happen */
           DBUG_ASSERT(false);
-          return &my_empty_string;
+          return make_empty_result();
         }
         to+= rc;
         break;
@@ -2291,7 +2295,7 @@ String *Item_func_make_set::val_str(String *str)
 	  else
 	  {
 	    if (tmp_str.copy(*res))		// Don't use 'str'
-	      return &my_empty_string;
+              return make_empty_result();
 	    result= &tmp_str;
 	  }
 	}
@@ -2301,11 +2305,11 @@ String *Item_func_make_set::val_str(String *str)
 	  {					// Copy data to tmp_str
 	    if (tmp_str.alloc(result->length()+res->length()+1) ||
 		tmp_str.copy(*result))
-	      return &my_empty_string;
+              return make_empty_result();
 	    result= &tmp_str;
 	  }
 	  if (tmp_str.append(STRING_WITH_LEN(","), &my_charset_bin) || tmp_str.append(*res))
-	    return &my_empty_string;
+            return make_empty_result();
 	}
       }
     }
@@ -2444,7 +2448,7 @@ String *Item_func_repeat::val_str(String *str)
   null_value= 0;
 
   if (count <= 0 && (count == 0 || !args[1]->unsigned_flag))
-    return &my_empty_string;
+    return make_empty_result();
 
   /* Assumes that the maximum length of a String is < INT_MAX32. */
   /* Bounds check on count:  If this is triggered, we will error. */
@@ -2752,7 +2756,7 @@ String *Item_func_conv::val_str(String *str)
 
   ptr= longlong2str(dec, ans, to_base, 1);
   if (str->copy(ans, (uint32) (ptr-ans), default_charset()))
-    return &my_empty_string;
+    return make_empty_result();
   return str;
 }
 
@@ -2762,22 +2766,16 @@ String *Item_func_conv_charset::val_str(String *str)
   DBUG_ASSERT(fixed == 1);
   if (use_cached_value)
     return null_value ? 0 : &str_value;
-  /* 
-    Here we don't pass 'str' as a parameter to args[0]->val_str()
-    as 'str' may point to 'str_value' (e.g. see Item::save_in_field()),
-    which we use below to convert string. 
-    Use argument's 'str_value' instead.
-  */
-  String *arg= args[0]->val_str(&args[0]->str_value);
+  String *arg= args[0]->val_str(str);
   uint dummy_errors;
   if (!arg)
   {
     null_value=1;
     return 0;
   }
-  null_value= str_value.copy(arg->ptr(),arg->length(),arg->charset(),
+  null_value= tmp_value.copy(arg->ptr(), arg->length(), arg->charset(),
                              conv_charset, &dummy_errors);
-  return null_value ? 0 : check_well_formed_result(&str_value);
+  return null_value ? 0 : check_well_formed_result(&tmp_value);
 }
 
 void Item_func_conv_charset::fix_length_and_dec()
@@ -2919,7 +2917,7 @@ String *Item_func_hex::val_str(String *str)
       return 0;
     ptr= longlong2str(dec,ans,16,1);
     if (str->copy(ans,(uint32) (ptr-ans),default_charset()))
-      return &my_empty_string;			// End of memory
+      return make_empty_result();			// End of memory
     return str;
   }
 
@@ -3219,14 +3217,68 @@ String *Item_func_quote::val_str(String *str)
   }
 
   arg_length= arg->length();
-  new_length= arg_length+2; /* for beginning and ending ' signs */
 
-  for (from= (char*) arg->ptr(), end= from + arg_length; from < end; from++)
-    new_length+= get_esc_bit(escmask, (uchar) *from);
+  if (collation.collation->mbmaxlen == 1)
+  {
+    new_length= arg_length + 2; /* for beginning and ending ' signs */
+    for (from= (char*) arg->ptr(), end= from + arg_length; from < end; from++)
+      new_length+= get_esc_bit(escmask, (uchar) *from);
+  }
+  else
+  {
+    new_length= (arg_length * 2) +  /* For string characters */
+                (2 * collation.collation->mbmaxlen); /* For quotes */
+  }
 
   if (tmp_value.alloc(new_length))
     goto null;
 
+  if (collation.collation->mbmaxlen > 1)
+  {
+    CHARSET_INFO *cs= collation.collation;
+    int mblen;
+    uchar *to_end;
+    to= (char*) tmp_value.ptr();
+    to_end= (uchar*) to + new_length;
+
+    /* Put leading quote */
+    if ((mblen= cs->cset->wc_mb(cs, '\'', (uchar *) to, to_end)) <= 0)
+      goto null;
+    to+= mblen;
+
+    for (start= (char*) arg->ptr(), end= start + arg_length; start < end; )
+    {
+      my_wc_t wc;
+      bool escape;
+      if ((mblen= cs->cset->mb_wc(cs, &wc, (uchar*) start, (uchar*) end)) <= 0)
+        goto null;
+      start+= mblen;
+      switch (wc) {
+        case 0:      escape= 1; wc= '0'; break;
+        case '\032': escape= 1; wc= 'Z'; break;
+        case '\'':   escape= 1; break;
+        case '\\':   escape= 1; break;
+        default:     escape= 0; break;
+      }
+      if (escape)
+      {
+        if ((mblen= cs->cset->wc_mb(cs, '\\', (uchar*) to, to_end)) <= 0)
+          goto null;
+        to+= mblen;
+      }
+      if ((mblen= cs->cset->wc_mb(cs, wc, (uchar*) to, to_end)) <= 0)
+        goto null;
+      to+= mblen;
+    }
+
+    /* Put trailing quote */
+    if ((mblen= cs->cset->wc_mb(cs, '\'', (uchar *) to, to_end)) <= 0)
+      goto null;
+    to+= mblen;
+    new_length= to - tmp_value.ptr();
+    goto ret;
+  }
+
   /*
     We replace characters from the end to the beginning
   */
@@ -3258,6 +3310,8 @@ String *Item_func_quote::val_str(String *str)
     }
   }
   *to= '\'';
+
+ret:
   tmp_value.length(new_length);
   tmp_value.set_charset(collation.collation);
   null_value= 0;