Added --sql-mode=NO_UNSIGNED_SUBTRACTION

Docs/manual.texi

@@ -8133,15 +8133,17 @@ than it had in 3.23.
 @item
 The result of all bitwise operators @code{|}, @code{&}, @code{<<},
 @code{>>} and @code{~} is now unsigned.  This may cause problems if your
-are using them in a context where you want an signed result. @xref{Cast
-Functions}.
+are using them in a context where you want an signed result.
+@xref{Cast Functions}.
 @item
 @strong{NOTE:} When you use subtraction between integers values where
 one is of type @code{UNSIGNED}, the result will be unsigned!  In other
 words, before upgrading to MySQL 4.0, you should check your application
-for cases where you are subtracting a value from an unsigned entity
-and want a negative answer or subtracting an unsigned value from a an
-integer column. @xref{Cast Functions}.
+for cases where you are subtracting a value from an unsigned entity and
+want a negative answer or subtracting an unsigned value from a an
+integer column. You can disable this behaviour by using the
+@code{--sql-mode=NO_UNSIGNED_SUBTRACTION} option when starting
+@code{mysqld}.  @xref{Cast Functions}.
 @item
 To use @code{MATCH ... AGAINST (... IN BOOLEAN MODE)} with your tables,
 you need to rebuild them with @code{ALTER TABLE table_name TYPE=MyISAM},
@@ -19873,6 +19875,8 @@ Means that the thread is flushing the changed table data to disk and
 closing the used tables. This should be a fast operation.  If not, then
 you should check that you don't have a full disk or that the disk is not
 in very heavy use.
+@item @code{Connect Out}
+Slave connecting to master.
 @item @code{Copying to tmp table on disk}
 The temporary result set was larger than @code{tmp_table_size} and the
 thread is now changing the in memory based temporary table to a disk
@@ -32000,6 +32004,12 @@ SELECT (unsigned_column_1+0.0)-(unsigned_column_2+0.0);
 The idea is that the columns are converted to floating point before doing
 the subtraction.
 
+If you get a problem with @code{UNSIGNED} columns in your old MySQL
+application when porting to MySQL 4.0, you can use the
+@code{--sql-mode=NO_UNSIGNED_SUBTRACTION} option when starting
+@code{mysqld}.  Note however that as long as you use this, you will not
+be able to efficiently use the @code{UNSIGNED BIGINT} column type.
+
 @node Other Functions, Group by functions, Cast Functions, Functions
 @subsection Other Functions
 
@@ -48361,6 +48371,10 @@ Our TODO section contains what we plan to have in 4.0. @xref{TODO MySQL 4.0}.
 
 @itemize @bullet
 @item
+Added sql-mode flag @code{NO_UNSIGNED_SUBTRACTION} to disable unsigned
+arithmetic rules when it comes to subtraction. (This will make MySQL 4.0
+behave more closely to 3.23 with @code{UNSIGNED} columns).
+@item
 Added @code{WITH MAX_QUERIES_PER_HOUR=#} to @code{GRANT} command.
 @item
 The type returned for all bit functions (@code{|}, @code{<<} ...) are now of
@@ -48473,7 +48487,7 @@ Added support for @code{MATCH ... AGAINST(... IN BOOLEAN MODE)}.
 @code{ALTER TABLE tablename TYPE=MyISAM} to be
 able to use boolean fulltext search}.
 @item
-@code{LOCATE()} and @code{INSTR()} are case sensitive if neither
+@code{LOCATE()} and @code{INSTR()} are now case sensitive if either
 argument is a binary string.
 @item
 Changed @code{RAND()} initialization so that @code{RAND(N)} and

sql/item_func.cc

@@ -280,6 +280,21 @@ longlong Item_func_plus::val_int()
   return (longlong) Item_func_plus::val();
 }
 
+
+/*
+  The following function is here to allow the user to force
+  subtraction of UNSIGNED BIGINT to return negative values.
+*/
+
+void Item_func_minus::fix_length_and_dec()
+{
+  Item_num_op::fix_length_and_dec();
+  if (unsigned_flag &&
+      (current_thd->sql_mode & MODE_NO_UNSIGNED_SUBTRACTION))
+    unsigned_flag=0;
+}
+
+
 double Item_func_minus::val()
 {
   double value=args[0]->val() - args[1]->val();

sql/item_func.h

@@ -233,8 +233,10 @@ public:
   const char *func_name() const { return "-"; }
   double val();
   longlong val_int();
+  void fix_length_and_dec();
 };
 
+
 class Item_func_mul :public Item_num_op
 {
 public:

sql/mysql_priv.h

@@ -187,6 +187,7 @@ char* query_table_status(THD *thd,const char *db,const char *table_name);
 #define MODE_IGNORE_SPACE		8
 #define MODE_SERIALIZABLE		16
 #define MODE_ONLY_FULL_GROUP_BY		32
+#define MODE_NO_UNSIGNED_SUBTRACTION	64
 
 #define RAID_BLOCK_SIZE 1024
 

sql/mysqld.cc

@@ -351,7 +351,7 @@ time_t start_time;
 ulong opt_sql_mode = 0L;
 const char *sql_mode_names[] =
 { "REAL_AS_FLOAT", "PIPES_AS_CONCAT", "ANSI_QUOTES", "IGNORE_SPACE",
-  "SERIALIZE","ONLY_FULL_GROUP_BY", NullS };
+  "SERIALIZE","ONLY_FULL_GROUP_BY", "NO_UNSIGNED_SUBTRACTION",NullS };
 TYPELIB sql_mode_typelib= {array_elements(sql_mode_names)-1,"",
 			   sql_mode_names};
 
@@ -486,7 +486,6 @@ static void close_connections(void)
     HANDLE hTempPipe = &hPipe;
     DBUG_PRINT( "quit", ("Closing named pipes") );
     hPipe = INVALID_HANDLE_VALUE;
-    CancelIo( hTempPipe );
     DisconnectNamedPipe( hTempPipe );
     CloseHandle( hTempPipe );
   }
@@ -3411,7 +3410,8 @@ static void usage(void)
   -t, --tmpdir=path	Path for temporary files\n\
   --sql-mode=option[,option[,option...]] where option can be one of:\n\
                         REAL_AS_FLOAT, PIPES_AS_CONCAT, ANSI_QUOTES,\n\
-                        IGNORE_SPACE, SERIALIZE, ONLY_FULL_GROUP_BY.\n\
+                        IGNORE_SPACE, SERIALIZE, ONLY_FULL_GROUP_BY,\n\
+			NO_UNSIGNED_SUBTRACTION.\n\
   --transaction-isolation\n\
 		        Default transaction isolation level\n\
   --temp-pool           Use a pool of temporary files\n\

sql/slave.cc

@@ -1541,7 +1541,7 @@ static int exec_relay_log_event(THD* thd, RELAY_LOG_INFO* rli)
       */
       /* TODO: I/O thread should not even log events with the same server id */
       rli->inc_pos(ev->get_event_len(),
-		   type_code != STOP_EVENT ? ev->log_pos : 0,
+		   type_code != STOP_EVENT ? ev->log_pos : LL(0),
 		   1/* skip lock*/);
       flush_relay_log_info(rli);
       if (rli->slave_skip_counter && /* protect against common user error of
@@ -2297,7 +2297,6 @@ Log_event* next_event(RELAY_LOG_INFO* rli)
 	DBUG_ASSERT(rli->cur_log_fd >= 0);
 	my_close(rli->cur_log_fd, MYF(MY_WME));
 	rli->cur_log_fd = -1; 
-	int error;
 	
 	// purge_first_log will properly set up relay log coordinates in rli 
 	if (rli->relay_log.purge_first_log(rli))

sql/slave.h

@@ -176,7 +176,7 @@ typedef struct st_relay_log_info
     pending += val;
   }
   // TODO: this probably needs to be fixed
-  inline void inc_pos(ulonglong val, uint32 log_pos, bool skip_lock=0)
+  inline void inc_pos(ulonglong val, ulonglong log_pos, bool skip_lock=0)
   {
     if (!skip_lock)
       pthread_mutex_lock(&data_lock);

sql/sql_rename.cc

@@ -35,8 +35,10 @@ bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list)
   TABLE_LIST *lock_table,*ren_table=0;
   DBUG_ENTER("mysql_rename_tables");
 
-  /* Avoid problems with a rename on a table that we have locked or
-     if the user is trying to to do this in a transcation context */
+  /*
+    Avoid problems with a rename on a table that we have locked or
+    if the user is trying to to do this in a transcation context
+  */
 
   if (thd->locked_tables || thd->active_transaction())
   {