Reduce usage of strlen()

Changes:
- To detect automatic strlen() I removed the methods in String that
  uses 'const char *' without a length:
  - String::append(const char*)
  - Binary_string(const char *str)
  - String(const char *str, CHARSET_INFO *cs)
  - append_for_single_quote(const char *)
  All usage of append(const char*) is changed to either use
  String::append(char), String::append(const char*, size_t length) or
  String::append(LEX_CSTRING)
- Added STRING_WITH_LEN() around constant string arguments to
  String::append()
- Added overflow argument to escape_string_for_mysql() and
  escape_quotes_for_mysql() instead of returning (size_t) -1 on overflow.
  This was needed as most usage of the above functions never tested the
  result for -1 and would have given wrong results or crashes in case
  of overflows.
- Added Item_func_or_sum::func_name_cstring(), which returns LEX_CSTRING.
  Changed all Item_func::func_name()'s to func_name_cstring()'s.
  The old Item_func_or_sum::func_name() is now an inline function that
  returns func_name_cstring().str.
- Changed Item::mode_name() and Item::func_name_ext() to return
  LEX_CSTRING.
- Changed for some functions the name argument from const char * to
  to const LEX_CSTRING &:
  - Item::Item_func_fix_attributes()
  - Item::check_type_...()
  - Type_std_attributes::agg_item_collations()
  - Type_std_attributes::agg_item_set_converter()
  - Type_std_attributes::agg_arg_charsets...()
  - Type_handler_hybrid_field_type::aggregate_for_result()
  - Type_handler_geometry::check_type_geom_or_binary()
  - Type_handler::Item_func_or_sum_illegal_param()
  - Predicant_to_list_comparator::add_value_skip_null()
  - Predicant_to_list_comparator::add_value()
  - cmp_item_row::prepare_comparators()
  - cmp_item_row::aggregate_row_elements_for_comparison()
  - Cursor_ref::print_func()
- Removes String_space() as it was only used in one cases and that
  could be simplified to not use String_space(), thanks to the fixed
  my_vsnprintf().
- Added some const LEX_CSTRING's for common strings:
  - NULL_clex_str, DATA_clex_str, INDEX_clex_str.
- Changed primary_key_name to a LEX_CSTRING
- Renamed String::set_quick() to String::set_buffer_if_not_allocated() to
  clarify what the function really does.
- Rename of protocol function:
  bool store(const char *from, CHARSET_INFO *cs) to
  bool store_string_or_null(const char *from, CHARSET_INFO *cs).
  This was done to both clarify the difference between this 'store' function
  and also to make it easier to find unoptimal usage of store() calls.
- Added Protocol::store(const LEX_CSTRING*, CHARSET_INFO*)
- Changed some 'const char*' arrays to instead be of type LEX_CSTRING.
- class Item_func_units now used LEX_CSTRING for name.

Other things:
- Fixed a bug in mysql.cc:construct_prompt() where a wrong escape character
  in the prompt would cause some part of the prompt to be duplicated.
- Fixed a lot of instances where the length of the argument to
  append is known or easily obtain but was not used.
- Removed some not needed 'virtual' definition for functions that was
  inherited from the parent. I added override to these.
- Fixed Ordered_key::print() to preallocate needed buffer. Old code could
  case memory overruns.
- Simplified some loops when adding char * to a String with delimiters.

1 files changed, 62 insertions, 40 deletions

diff --git a/storage/spider/spd_db_mysql.cc b/storage/spider/spd_db_mysql.cc
index 6821e36e445..5b257444bfc 100644
--- a/storage/spider/spd_db_mysql.cc
+++ b/storage/spider/spd_db_mysql.cc
@@ -3825,13 +3825,14 @@ size_t spider_db_mbase::escape_string(
   const char *from,
   size_t from_length
 ) {
+  my_bool overflow;
   DBUG_ENTER("spider_db_mbase::escape_string");
   DBUG_PRINT("info",("spider this=%p", this));
   if (db_conn->server_status & SERVER_STATUS_NO_BACKSLASH_ESCAPES)
     DBUG_RETURN(escape_quotes_for_mysql(db_conn->charset, to, 0,
-      from, from_length));
+      from, from_length, &overflow));
   DBUG_RETURN(escape_string_for_mysql(db_conn->charset, to, 0,
-    from, from_length));
+    from, from_length, &overflow));
 }
 
 bool spider_db_mbase::have_lock_table_list()
@@ -5799,6 +5800,8 @@ int spider_db_mbase_util::open_item_func(
   Item *item, **item_list = item_func->arguments();
   Field *field;
   uint roop_count, item_count = item_func->argument_count(), start_item = 0;
+  LEX_CSTRING org_func_name= {SPIDER_SQL_NULL_CHAR_STR,
+                              SPIDER_SQL_NULL_CHAR_LEN};
   const char *func_name = SPIDER_SQL_NULL_CHAR_STR,
     *separator_str = SPIDER_SQL_NULL_CHAR_STR,
     *last_str = SPIDER_SQL_NULL_CHAR_STR;
@@ -5826,8 +5829,9 @@ int spider_db_mbase_util::open_item_func(
       last_str_length = SPIDER_SQL_IS_NOT_NULL_LEN;
       break;
     case Item_func::UNKNOWN_FUNC:
-      func_name = (char*) item_func->func_name();
-      func_name_length = strlen(func_name);
+      org_func_name= item_func->func_name_cstring();
+      func_name= org_func_name.str;
+      func_name_length = org_func_name.length;
       DBUG_PRINT("info",("spider func_name = %s", func_name));
       DBUG_PRINT("info",("spider func_name_length = %d", func_name_length));
       if (func_name_length == 1 &&
@@ -6028,9 +6032,10 @@ int spider_db_mbase_util::open_item_func(
             {
               const char *child_func_name;
               int child_func_name_length;
+              LEX_CSTRING org_func_name= ifunc->func_name_cstring();
               DBUG_PRINT("info",("spider child is UNKNOWN_FUNC"));
-              child_func_name = (char*) ifunc->func_name();
-              child_func_name_length = strlen(child_func_name);
+              child_func_name = org_func_name.str;
+              child_func_name_length =  org_func_name.length;
               DBUG_PRINT("info",("spider child func_name is %s", child_func_name));
               if (
                 child_func_name_length == 10 &&
@@ -6066,9 +6071,10 @@ int spider_db_mbase_util::open_item_func(
             {
               const char *child_func_name;
               int child_func_name_length;
+              LEX_CSTRING org_func_name= ifunc->func_name_cstring();
               DBUG_PRINT("info",("spider child is UNKNOWN_FUNC"));
-              child_func_name = (char*) ifunc->func_name();
-              child_func_name_length = strlen(child_func_name);
+              child_func_name = org_func_name.str;
+              child_func_name_length =  org_func_name.length;
               DBUG_PRINT("info",("spider child func_name is %s", child_func_name));
               if (
                 child_func_name_length == 10 &&
@@ -6200,9 +6206,10 @@ int spider_db_mbase_util::open_item_func(
             {
               const char *child_func_name;
               int child_func_name_length;
+              LEX_CSTRING org_func_name= ifunc->func_name_cstring();
               DBUG_PRINT("info",("spider child is UNKNOWN_FUNC"));
-              child_func_name = (char*) ifunc->func_name();
-              child_func_name_length = strlen(child_func_name);
+              child_func_name = org_func_name.str;
+              child_func_name_length =  org_func_name.length;
               DBUG_PRINT("info",("spider child func_name is %s", child_func_name));
               if (
                 child_func_name_length == 10 &&
@@ -6254,9 +6261,10 @@ int spider_db_mbase_util::open_item_func(
             {
               const char *child_func_name;
               int child_func_name_length;
+              LEX_CSTRING org_func_name= ifunc->func_name_cstring();
               DBUG_PRINT("info",("spider child is UNKNOWN_FUNC"));
-              child_func_name = (char*) ifunc->func_name();
-              child_func_name_length = strlen(child_func_name);
+              child_func_name = org_func_name.str;
+              child_func_name_length =  org_func_name.length;
               DBUG_PRINT("info",("spider child func_name is %s", child_func_name));
               if (
                 child_func_name_length == 10 &&
@@ -6295,9 +6303,10 @@ int spider_db_mbase_util::open_item_func(
             {
               const char *child_func_name;
               int child_func_name_length;
+              LEX_CSTRING org_func_name= ifunc->func_name_cstring();
               DBUG_PRINT("info",("spider child is UNKNOWN_FUNC"));
-              child_func_name = (char*) ifunc->func_name();
-              child_func_name_length = strlen(child_func_name);
+              child_func_name = org_func_name.str;
+              child_func_name_length =  org_func_name.length;
               DBUG_PRINT("info",("spider child func_name is %s", child_func_name));
               if (
                 child_func_name_length == 10 &&
@@ -6334,9 +6343,10 @@ int spider_db_mbase_util::open_item_func(
             {
               const char *child_func_name;
               int child_func_name_length;
+              LEX_CSTRING org_func_name= ifunc->func_name_cstring();
               DBUG_PRINT("info",("spider child is UNKNOWN_FUNC"));
-              child_func_name = (char*) ifunc->func_name();
-              child_func_name_length = strlen(child_func_name);
+              child_func_name = org_func_name.str;
+              child_func_name_length =  org_func_name.length;
               DBUG_PRINT("info",("spider child func_name is %s", child_func_name));
               if (
                 child_func_name_length == 10 &&
@@ -6389,9 +6399,10 @@ int spider_db_mbase_util::open_item_func(
             {
               const char *child_func_name;
               int child_func_name_length;
+              LEX_CSTRING org_func_name= ifunc->func_name_cstring();
               DBUG_PRINT("info",("spider child is UNKNOWN_FUNC"));
-              child_func_name = (char*) ifunc->func_name();
-              child_func_name_length = strlen(child_func_name);
+              child_func_name = org_func_name.str;
+              child_func_name_length =  org_func_name.length;
               DBUG_PRINT("info",("spider child func_name is %s", child_func_name));
               if (
                 child_func_name_length == 10 &&
@@ -6488,9 +6499,10 @@ int spider_db_mbase_util::open_item_func(
           {
             const char *child_func_name;
             int child_func_name_length;
+            LEX_CSTRING org_func_name= ifunc->func_name_cstring();
             DBUG_PRINT("info",("spider child is UNKNOWN_FUNC"));
-            child_func_name = (char*) ifunc->func_name();
-            child_func_name_length = strlen(child_func_name);
+            child_func_name = org_func_name.str;
+            child_func_name_length =  org_func_name.length;
             DBUG_PRINT("info",("spider child func_name is %s", child_func_name));
             if (
               child_func_name_length == 10 &&
@@ -6576,8 +6588,9 @@ int spider_db_mbase_util::open_item_func(
       }
       if (str)
       {
-        func_name = (char*) item_func->func_name();
-        func_name_length = strlen(func_name);
+        LEX_CSTRING org_func_name= item_func->func_name_cstring();
+        func_name = org_func_name.str;
+        func_name_length = org_func_name.length;
         if (str->reserve(func_name_length + SPIDER_SQL_SPACE_LEN))
           DBUG_RETURN(HA_ERR_OUT_OF_MEM);
         str->q_append(func_name, func_name_length);
@@ -6587,8 +6600,9 @@ int spider_db_mbase_util::open_item_func(
     case Item_func::NEG_FUNC:
       if (str)
       {
-        func_name = (char*) item_func->func_name();
-        func_name_length = strlen(func_name);
+        LEX_CSTRING org_func_name= item_func->func_name_cstring();
+        func_name = org_func_name.str;
+        func_name_length = org_func_name.length;
         if (str->reserve(func_name_length + SPIDER_SQL_SPACE_LEN))
           DBUG_RETURN(HA_ERR_OUT_OF_MEM);
         str->q_append(func_name, func_name_length);
@@ -6621,8 +6635,9 @@ int spider_db_mbase_util::open_item_func(
         separator_str = SPIDER_SQL_AND_STR;
         separator_str_length = SPIDER_SQL_AND_LEN;
       } else {
-        func_name = (char*) item_func->func_name();
-        func_name_length = strlen(func_name);
+        LEX_CSTRING org_func_name= item_func->func_name_cstring();
+        func_name = org_func_name.str;
+        func_name_length = org_func_name.length;
         separator_str = SPIDER_SQL_AND_STR;
         separator_str_length = SPIDER_SQL_AND_LEN;
       }
@@ -6635,8 +6650,9 @@ int spider_db_mbase_util::open_item_func(
         DBUG_RETURN(ER_SPIDER_COND_SKIP_NUM);
       if (str)
       {
-        func_name = (char*) item_func->func_name();
-        func_name_length = strlen(func_name);
+        LEX_CSTRING org_func_name= item_func->func_name_cstring();
+        func_name = org_func_name.str;
+        func_name_length = org_func_name.length;
         DBUG_PRINT("info",("spider func_name = %s", func_name));
         DBUG_PRINT("info",("spider func_name_length = %d", func_name_length));
         if (str->reserve(func_name_length + SPIDER_SQL_OPEN_PAREN_LEN))
@@ -6714,8 +6730,9 @@ int spider_db_mbase_util::open_item_func(
     case Item_func::SP_OVERLAPS_FUNC:
       if (str)
       {
-        func_name = (char*) item_func->func_name();
-        func_name_length = strlen(func_name);
+        LEX_CSTRING org_func_name= item_func->func_name_cstring();
+        func_name = org_func_name.str;
+        func_name_length = org_func_name.length;
         DBUG_PRINT("info",("spider func_name = %s", func_name));
         DBUG_PRINT("info",("spider func_name_length = %d", func_name_length));
         if (str->reserve(
@@ -6746,8 +6763,9 @@ int spider_db_mbase_util::open_item_func(
     case Item_func::GT_FUNC:
       if (str)
       {
-        func_name = (char*) item_func->func_name();
-        func_name_length = strlen(func_name);
+        LEX_CSTRING org_func_name= item_func->func_name_cstring();
+        func_name = org_func_name.str;
+        func_name_length = org_func_name.length;
       }
       break;
     case Item_func::LIKE_FUNC:
@@ -6761,8 +6779,9 @@ int spider_db_mbase_util::open_item_func(
          }
          else
          {
-            func_name = (char*)item_func->func_name();
-            func_name_length = strlen(func_name);
+           LEX_CSTRING org_func_name= item_func->func_name_cstring();
+           func_name = org_func_name.str;
+           func_name_length = org_func_name.length;
          }
       }
       break;
@@ -6777,8 +6796,9 @@ int spider_db_mbase_util::open_item_func(
         DBUG_RETURN(ER_SPIDER_COND_SKIP_NUM);
       if (str)
       {
-        func_name = (char*) item_func->func_name();
-        func_name_length = strlen(func_name);
+        LEX_CSTRING org_func_name= item_func->func_name_cstring();
+        func_name = org_func_name.str;
+        func_name_length = org_func_name.length;
       }
       break;
   }
@@ -6911,8 +6931,9 @@ int spider_db_mbase_util::open_item_sum_func(
     case Item_sum::MIN_FUNC:
     case Item_sum::MAX_FUNC:
       {
-        const char *func_name = item_sum->func_name();
-        uint func_name_length = strlen(func_name);
+        LEX_CSTRING org_func_name= item_sum->func_name_cstring();
+        const char *func_name = org_func_name.str;
+        uint func_name_length = org_func_name.length;
         Item *item, **args = item_sum->get_args();
         if (str)
         {
@@ -6957,8 +6978,9 @@ int spider_db_mbase_util::open_item_sum_func(
       {
         if (!use_fields)
           DBUG_RETURN(ER_SPIDER_COND_SKIP_NUM);
-        const char *func_name = item_sum->func_name();
-        uint func_name_length = strlen(func_name);
+        LEX_CSTRING org_func_name= item_sum->func_name_cstring();
+        const char *func_name = org_func_name.str;
+        uint func_name_length = org_func_name.length;
         Item *item, **args = item_sum->get_args();
         if (str)
         {