MDEV-6353 my_ismbchar() and my_mbcharlen() refactoring

5 files changed, 46 insertions, 34 deletions

diff --git a/sql/create_options.cc b/sql/create_options.cc
index 66515be05b8..3011c4b2d7e 100644
--- a/sql/create_options.cc
+++ b/sql/create_options.cc
@@ -184,7 +184,7 @@ static bool set_one_value(ha_create_table_option *opt,
       {
         for (end=start;
              *end && *end != ',';
-             end+= my_mbcharlen(system_charset_info, *end)) /* no-op */;
+             end++) /* no-op */;
         if (!my_strnncoll(system_charset_info,
                           (uchar*)start, end-start,
                           (uchar*)value->str, value->length))
diff --git a/sql/debug_sync.cc b/sql/debug_sync.cc
index 8b3412eb732..b2a187b07cb 100644
--- a/sql/debug_sync.cc
+++ b/sql/debug_sync.cc
@@ -847,16 +847,16 @@ static bool debug_sync_set_action(THD *thd, st_debug_sync_action *action)
     to the string terminator ASCII NUL ('\0').
 */
 
-static char *debug_sync_token(char **token_p, uint *token_length_p, char *ptr)
+static char *debug_sync_token(char **token_p, uint *token_length_p,
+                              char *ptr, char *ptrend)
 {
   DBUG_ASSERT(token_p);
   DBUG_ASSERT(token_length_p);
   DBUG_ASSERT(ptr);
 
   /* Skip leading space */
-  while (my_isspace(system_charset_info, *ptr))
-    ptr+= my_mbcharlen(system_charset_info, (uchar) *ptr);
-
+  ptr+= system_charset_info->cset->scan(system_charset_info,
+                                        ptr, ptrend, MY_SEQ_SPACES);
   if (!*ptr)
   {
     ptr= NULL;
@@ -867,8 +867,8 @@ static char *debug_sync_token(char **token_p, uint *token_length_p, char *ptr)
   *token_p= ptr;
 
   /* Find token end. */
-  while (*ptr && !my_isspace(system_charset_info, *ptr))
-    ptr+= my_mbcharlen(system_charset_info, (uchar) *ptr);
+  ptr+= system_charset_info->cset->scan(system_charset_info,
+                                        ptr, ptrend, MY_SEQ_NONSPACES);
 
   /* Get token length. */
   *token_length_p= ptr - *token_p;
@@ -876,8 +876,9 @@ static char *debug_sync_token(char **token_p, uint *token_length_p, char *ptr)
   /* If necessary, terminate token. */
   if (*ptr)
   {
+    DBUG_ASSERT(ptr < ptrend);
     /* Get terminator character length. */
-    uint mbspacelen= my_mbcharlen(system_charset_info, (uchar) *ptr);
+    uint mbspacelen= my_charlen_fix(system_charset_info, ptr, ptrend);
 
     /* Terminate token. */
     *ptr= '\0';
@@ -886,8 +887,8 @@ static char *debug_sync_token(char **token_p, uint *token_length_p, char *ptr)
     ptr+= mbspacelen;
 
     /* Skip trailing space */
-    while (my_isspace(system_charset_info, *ptr))
-      ptr+= my_mbcharlen(system_charset_info, (uchar) *ptr);
+    ptr+= system_charset_info->cset->scan(system_charset_info,
+                                          ptr, ptrend, MY_SEQ_SPACES);
   }
 
  end:
@@ -917,7 +918,8 @@ static char *debug_sync_token(char **token_p, uint *token_length_p, char *ptr)
     undefined in this case.
 */
 
-static char *debug_sync_number(ulong *number_p, char *actstrptr)
+static char *debug_sync_number(ulong *number_p, char *actstrptr,
+                                                char *actstrend)
 {
   char                  *ptr;
   char                  *ept;
@@ -927,7 +929,7 @@ static char *debug_sync_number(ulong *number_p, char *actstrptr)
   DBUG_ASSERT(actstrptr);
 
   /* Get token from string. */
-  if (!(ptr= debug_sync_token(&token, &token_length, actstrptr)))
+  if (!(ptr= debug_sync_token(&token, &token_length, actstrptr, actstrend)))
     goto end;
 
   *number_p= strtoul(token, &ept, 10);
@@ -971,7 +973,7 @@ static char *debug_sync_number(ulong *number_p, char *actstrptr)
     for the string.
 */
 
-static bool debug_sync_eval_action(THD *thd, char *action_str)
+static bool debug_sync_eval_action(THD *thd, char *action_str, char *action_end)
 {
   st_debug_sync_action  *action= NULL;
   const char            *errmsg;
@@ -986,7 +988,7 @@ static bool debug_sync_eval_action(THD *thd, char *action_str)
   /*
     Get debug sync point name. Or a special command.
   */
-  if (!(ptr= debug_sync_token(&token, &token_length, action_str)))
+  if (!(ptr= debug_sync_token(&token, &token_length, action_str, action_end)))
   {
     errmsg= "Missing synchronization point name";
     goto err;
@@ -1009,7 +1011,7 @@ static bool debug_sync_eval_action(THD *thd, char *action_str)
   /*
     Get kind of action to be taken at sync point.
   */
-  if (!(ptr= debug_sync_token(&token, &token_length, ptr)))
+  if (!(ptr= debug_sync_token(&token, &token_length, ptr, action_end)))
   {
     /* No action present. Try special commands. Token unchanged. */
 
@@ -1090,7 +1092,7 @@ static bool debug_sync_eval_action(THD *thd, char *action_str)
   if (!my_strcasecmp(system_charset_info, token, "SIGNAL"))
   {
     /* It is SIGNAL. Signal name must follow. */
-    if (!(ptr= debug_sync_token(&token, &token_length, ptr)))
+    if (!(ptr= debug_sync_token(&token, &token_length, ptr, action_end)))
     {
       errmsg= "Missing signal name after action SIGNAL";
       goto err;
@@ -1108,7 +1110,7 @@ static bool debug_sync_eval_action(THD *thd, char *action_str)
     action->execute= 1;
 
     /* Get next token. If none follows, set action. */
-    if (!(ptr= debug_sync_token(&token, &token_length, ptr)))
+    if (!(ptr= debug_sync_token(&token, &token_length, ptr, action_end)))
       goto set_action;
   }
 
@@ -1118,7 +1120,7 @@ static bool debug_sync_eval_action(THD *thd, char *action_str)
   if (!my_strcasecmp(system_charset_info, token, "WAIT_FOR"))
   {
     /* It is WAIT_FOR. Wait_for signal name must follow. */
-    if (!(ptr= debug_sync_token(&token, &token_length, ptr)))
+    if (!(ptr= debug_sync_token(&token, &token_length, ptr, action_end)))
     {
       errmsg= "Missing signal name after action WAIT_FOR";
       goto err;
@@ -1137,7 +1139,7 @@ static bool debug_sync_eval_action(THD *thd, char *action_str)
     action->timeout= opt_debug_sync_timeout;
 
     /* Get next token. If none follows, set action. */
-    if (!(ptr= debug_sync_token(&token, &token_length, ptr)))
+    if (!(ptr= debug_sync_token(&token, &token_length, ptr, action_end)))
       goto set_action;
 
     /*
@@ -1146,14 +1148,14 @@ static bool debug_sync_eval_action(THD *thd, char *action_str)
     if (!my_strcasecmp(system_charset_info, token, "TIMEOUT"))
     {
       /* It is TIMEOUT. Number must follow. */
-      if (!(ptr= debug_sync_number(&action->timeout, ptr)))
+      if (!(ptr= debug_sync_number(&action->timeout, ptr, action_end)))
       {
         errmsg= "Missing valid number after TIMEOUT";
         goto err;
       }
 
       /* Get next token. If none follows, set action. */
-      if (!(ptr= debug_sync_token(&token, &token_length, ptr)))
+      if (!(ptr= debug_sync_token(&token, &token_length, ptr, action_end)))
         goto set_action;
     }
   }
@@ -1174,14 +1176,14 @@ static bool debug_sync_eval_action(THD *thd, char *action_str)
     }
 
     /* Number must follow. */
-    if (!(ptr= debug_sync_number(&action->execute, ptr)))
+    if (!(ptr= debug_sync_number(&action->execute, ptr, action_end)))
     {
       errmsg= "Missing valid number after EXECUTE";
       goto err;
     }
 
     /* Get next token. If none follows, set action. */
-    if (!(ptr= debug_sync_token(&token, &token_length, ptr)))
+    if (!(ptr= debug_sync_token(&token, &token_length, ptr, action_end)))
       goto set_action;
   }
 
@@ -1191,14 +1193,14 @@ static bool debug_sync_eval_action(THD *thd, char *action_str)
   if (!my_strcasecmp(system_charset_info, token, "HIT_LIMIT"))
   {
     /* Number must follow. */
-    if (!(ptr= debug_sync_number(&action->hit_limit, ptr)))
+    if (!(ptr= debug_sync_number(&action->hit_limit, ptr, action_end)))
     {
       errmsg= "Missing valid number after HIT_LIMIT";
       goto err;
     }
 
     /* Get next token. If none follows, set action. */
-    if (!(ptr= debug_sync_token(&token, &token_length, ptr)))
+    if (!(ptr= debug_sync_token(&token, &token_length, ptr, action_end)))
       goto set_action;
   }
 
@@ -1246,7 +1248,7 @@ static bool debug_sync_eval_action(THD *thd, char *action_str)
     terminators in the string. So we need to take a copy here.
 */
 
-bool debug_sync_update(THD *thd, char *val_str)
+bool debug_sync_update(THD *thd, char *val_str, size_t len)
 {
   DBUG_ENTER("debug_sync_update");
   DBUG_PRINT("debug_sync", ("set action: '%s'", val_str));
@@ -1255,8 +1257,9 @@ bool debug_sync_update(THD *thd, char *val_str)
     debug_sync_eval_action() places '\0' in the string, which itself
     must be '\0' terminated.
   */
+  DBUG_ASSERT(val_str[len] == '\0');
   DBUG_RETURN(opt_debug_sync_timeout ?
-              debug_sync_eval_action(thd, val_str) :
+              debug_sync_eval_action(thd, val_str, val_str + len) :
               FALSE);
 }
 
@@ -1592,7 +1595,7 @@ bool debug_sync_set_action(THD *thd, const char *action_str, size_t len)
   DBUG_ASSERT(action_str);
   
   value= strmake_root(thd->mem_root, action_str, len);
-  rc= debug_sync_eval_action(thd, value);
+  rc= debug_sync_eval_action(thd, value, value + len);
   DBUG_RETURN(rc);
 }
 
diff --git a/sql/debug_sync.h b/sql/debug_sync.h
index bf1b3167dbc..339a21139b1 100644
--- a/sql/debug_sync.h
+++ b/sql/debug_sync.h
@@ -45,6 +45,9 @@ extern void debug_sync_init_thread(THD *thd);
 extern void debug_sync_end_thread(THD *thd);
 extern bool debug_sync_set_action(THD *thd, const char *action_str, size_t len);
 
+extern bool debug_sync_update(THD *thd, char *val_str, size_t len);
+extern uchar *debug_sync_value_ptr(THD *thd);
+
 #endif /* defined(ENABLED_DEBUG_SYNC) */
 
 #endif /* DEBUG_SYNC_INCLUDED */
diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index b1217cb1f9f..be950627f08 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -3235,7 +3235,7 @@ int select_export::send_data(List<Item> &items)
 
           if ((NEED_ESCAPING(*pos) ||
                (check_second_byte &&
-                my_mbcharlen(character_set_client, (uchar) *pos) == 2 &&
+                ((uchar) *pos) > 0x7F /* a potential MB2HEAD */ &&
                 pos + 1 < end &&
                 NEED_ESCAPING(pos[1]))) &&
               /*
diff --git a/sql/sys_vars.ic b/sql/sys_vars.ic
index 373f5834838..2488e804310 100644
--- a/sql/sys_vars.ic
+++ b/sql/sys_vars.ic
@@ -1434,6 +1434,9 @@ public:
 };
 
 #if defined(ENABLED_DEBUG_SYNC)
+
+#include "debug_sync.h"
+
 /**
   The class for @@debug_sync session-only variable
 */
@@ -1462,15 +1465,19 @@ public:
     String str(buff, sizeof(buff), system_charset_info), *res;
 
     if (!(res=var->value->val_str(&str)))
-      var->save_result.string_value.str= const_cast<char*>("");
+      var->save_result.string_value= empty_lex_str;
     else
-      var->save_result.string_value.str= thd->strmake(res->ptr(), res->length());
+    {
+      if (!thd->make_lex_string(&var->save_result.string_value,
+                                res->ptr(), res->length()))
+        return true;
+    }
     return false;
   }
   bool session_update(THD *thd, set_var *var)
   {
-    extern bool debug_sync_update(THD *thd, char *val_str);
-    return debug_sync_update(thd, var->save_result.string_value.str);
+    return debug_sync_update(thd, var->save_result.string_value.str,
+                                  var->save_result.string_value.length);
   }
   bool global_update(THD *thd, set_var *var)
   {
@@ -1488,7 +1495,6 @@ public:
   }
   uchar *session_value_ptr(THD *thd, const LEX_STRING *base)
   {
-    extern uchar *debug_sync_value_ptr(THD *thd);
     return debug_sync_value_ptr(thd);
   }
   uchar *global_value_ptr(THD *thd, const LEX_STRING *base)