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, 22 insertions, 19 deletions

diff --git a/storage/sphinx/ha_sphinx.cc b/storage/sphinx/ha_sphinx.cc
index 0ca08bc3c47..e2f1909e8e2 100644
--- a/storage/sphinx/ha_sphinx.cc
+++ b/storage/sphinx/ha_sphinx.cc
@@ -2325,30 +2325,32 @@ int ha_sphinx::write_row ( const byte * )
 	// SphinxQL inserts only, pretty much similar to abandoned federated
 	char sQueryBuf[1024];
 	char sValueBuf[1024];
-
 	String sQuery ( sQueryBuf, sizeof(sQueryBuf), &my_charset_bin );
 	String sValue ( sValueBuf, sizeof(sQueryBuf), &my_charset_bin );
+        const char *query;
 	sQuery.length ( 0 );
 	sValue.length ( 0 );
 
 	CSphSEThreadTable * pTable = GetTls ();
-	sQuery.append ( pTable && pTable->m_bReplace ? "REPLACE INTO " : "INSERT INTO " );
-	sQuery.append ( m_pShare->m_sIndex );
-	sQuery.append ( " (" );
+        query= pTable && pTable->m_bReplace ? "REPLACE INTO " : "INSERT INTO ";
+	sQuery.append (query, strlen(query));
+	sQuery.append ( m_pShare->m_sIndex, strlen(m_pShare->m_sIndex ));
+	sQuery.append (STRING_WITH_LEN(" (" ));
 
 	for ( Field ** ppField = table->field; *ppField; ppField++ )
 	{
-		sQuery.append ( (*ppField)->field_name.str );
+          sQuery.append ( (*ppField)->field_name.str,
+                          strlen((*ppField)->field_name.str));
 		if ( ppField[1] )
-			sQuery.append ( ", " );
+                      sQuery.append (STRING_WITH_LEN(", "));
 	}
-	sQuery.append ( ") VALUES (" );
+	sQuery.append (STRING_WITH_LEN( ") VALUES (" ));
 
 	for ( Field ** ppField = table->field; *ppField; ppField++ )
 	{
 		if ( (*ppField)->is_null() )
 		{
-			sQuery.append ( "''" );
+                        sQuery.append (STRING_WITH_LEN( "''" ));
 
 		} else
 		{
@@ -2360,23 +2362,23 @@ int ha_sphinx::write_row ( const byte * )
 				pConv->quick_fix_field();
 				unsigned int uTs = (unsigned int) pConv->val_int();
 
-				snprintf ( sValueBuf, sizeof(sValueBuf), "'%u'", uTs );
-				sQuery.append ( sValueBuf );
+				uint len= my_snprintf ( sValueBuf, sizeof(sValueBuf), "'%u'", uTs );
+				sQuery.append ( sValueBuf, len );
 
 			} else
 			{
 				(*ppField)->val_str ( &sValue );
-				sQuery.append ( "'" );
+				sQuery.append ( '\'' );
 				sValue.print ( &sQuery );
-				sQuery.append ( "'" );
+				sQuery.append ( '\'' );
 				sValue.length(0);
 			}
 		}
 
 		if ( ppField[1] )
-			sQuery.append ( ", " );
+                        sQuery.append (STRING_WITH_LEN(", "));
 	}
-	sQuery.append ( ")" );
+	sQuery.append ( ')' );
 
 	// FIXME? pretty inefficient to reconnect every time under high load,
 	// but this was intentionally written for a low load scenario..
@@ -2432,13 +2434,14 @@ int ha_sphinx::delete_row ( const byte * )
 	String sQuery ( sQueryBuf, sizeof(sQueryBuf), &my_charset_bin );
 	sQuery.length ( 0 );
 
-	sQuery.append ( "DELETE FROM " );
-	sQuery.append ( m_pShare->m_sIndex );
-	sQuery.append ( " WHERE id=" );
+	sQuery.append (STRING_WITH_LEN( "DELETE FROM " ));
+	sQuery.append ( m_pShare->m_sIndex, strlen(m_pShare->m_sIndex));
+	sQuery.append (STRING_WITH_LEN( " WHERE id=" ));
 
 	char sValue[32];
-	snprintf ( sValue, sizeof(sValue), "%lld", table->field[0]->val_int() );
-	sQuery.append ( sValue );
+	uint length= my_snprintf ( sValue, sizeof(sValue), "%lld",
+                                   table->field[0]->val_int() );
+	sQuery.append ( sValue, length );
 
 	// FIXME? pretty inefficient to reconnect every time under high load,
 	// but this was intentionally written for a low load scenario..