Fixes bug #13377. my_open() & my_create() functions changed to use

my_sopen() on win32 which allows to use FILE_SHARE_DELETE flag to 
allow deleting opened files. my_sopen() implementation is added to
support this functionality.


include/my_global.h:
  Fixes bug #13377. Added number of constants for share delete file
  open option.
include/my_sys.h:
  Fixes bug #13377. Added my_sopen function.
mysys/my_create.c:
  Fixes bug #13377. my_create() function changed to use my_sopen() and which allows
  to use FILE_SHARE_DELETE flag on win32, which helps in deleting opened files.
mysys/my_open.c:
  Fixes bug #13377. my_open() function changed to use my_sopen() on win32
  which allows to use FILE_SHARE_DELETE flag to allow deleting opened files.
sql/log.cc:
  Fixes bug #13377. Additional patch - remove reference counting for
  opened binlog files, introduced in initial patch of #13377.
sql/sql_class.h:
  Fixes bug #13377. Additional patch - remove reference counting for
  opened binlog files, introduced in initial patch of #13377.
sql/sql_repl.cc:
  Fixes bug #13377. Additional patch - remove reference counting for
  opened binlog files, introduced in initial patch of #13377.

1 files changed, 1 insertions, 61 deletions

diff --git a/sql/log.cc b/sql/log.cc
index 4b3d6698051..e42f1def27c 100644
--- a/sql/log.cc
+++ b/sql/log.cc
@@ -357,8 +357,7 @@ static int find_uniq_filename(char *name)
 MYSQL_LOG::MYSQL_LOG()
   :bytes_written(0), last_time(0), query_start(0), name(0),
    prepared_xids(0), log_type(LOG_CLOSED), file_id(1), open_count(1),
-   readers_count(0), reset_pending(FALSE), write_error(FALSE), inited(FALSE),
-   need_start_event(TRUE),
+   write_error(FALSE), inited(FALSE), need_start_event(TRUE),
    description_event_for_exec(0), description_event_for_queue(0)
 {
   /*
@@ -385,9 +384,7 @@ void MYSQL_LOG::cleanup()
     delete description_event_for_exec;
     (void) pthread_mutex_destroy(&LOCK_log);
     (void) pthread_mutex_destroy(&LOCK_index);
-    (void) pthread_mutex_destroy(&LOCK_readers);
     (void) pthread_cond_destroy(&update_cond);
-    (void) pthread_cond_destroy(&reset_cond);
   }
   DBUG_VOID_RETURN;
 }
@@ -432,9 +429,7 @@ void MYSQL_LOG::init_pthread_objects()
   inited= 1;
   (void) pthread_mutex_init(&LOCK_log,MY_MUTEX_INIT_SLOW);
   (void) pthread_mutex_init(&LOCK_index, MY_MUTEX_INIT_SLOW);
-  (void) pthread_mutex_init(&LOCK_readers, MY_MUTEX_INIT_SLOW);
   (void) pthread_cond_init(&update_cond, 0);
-  (void) pthread_cond_init(&reset_cond, 0);
 }
 
 const char *MYSQL_LOG::generate_name(const char *log_name,
@@ -938,12 +933,6 @@ bool MYSQL_LOG::reset_logs(THD* thd)
   pthread_mutex_lock(&LOCK_log);
   pthread_mutex_lock(&LOCK_index);
 
-  /* 
-    we need one more lock to block attempts to open a log while
-    we are waiting untill all log files will be closed
-  */
-  pthread_mutex_lock(&LOCK_readers);
-
   /*
     The following mutex is needed to ensure that no threads call
     'delete thd' as we would then risk missing a 'rollback' from this
@@ -966,19 +955,6 @@ bool MYSQL_LOG::reset_logs(THD* thd)
     goto err;
   }
 
-  reset_pending= TRUE;
-  /* 
-    send update signal just in case so that all reader threads waiting
-    for log update will leave wait condition
-  */
-  signal_update();
-  /* 
-    if there are active readers wait until all of them will 
-    release opened files 
-  */
-  while (readers_count)
-    pthread_cond_wait(&reset_cond, &LOCK_log);
-
   for (;;)
   {
     my_delete(linfo.log_file_name, MYF(MY_WME));
@@ -997,10 +973,7 @@ bool MYSQL_LOG::reset_logs(THD* thd)
   my_free((gptr) save_name, MYF(0));
 
 err:
-  reset_pending= FALSE;
-
   (void) pthread_mutex_unlock(&LOCK_thread_count);
-  pthread_mutex_unlock(&LOCK_readers);
   pthread_mutex_unlock(&LOCK_index);
   pthread_mutex_unlock(&LOCK_log);
   DBUG_RETURN(error);
@@ -2073,12 +2046,6 @@ void MYSQL_LOG::wait_for_update(THD* thd, bool is_slave)
 {
   const char *old_msg;
   DBUG_ENTER("wait_for_update");
-  
-  if (reset_pending)
-  {
-    pthread_mutex_unlock(&LOCK_log);
-    DBUG_VOID_RETURN;
-  }
 
   old_msg= thd->enter_cond(&update_cond, &LOCK_log,
                            is_slave ?
@@ -2330,33 +2297,6 @@ void MYSQL_LOG::signal_update()
   DBUG_VOID_RETURN;
 }
 
-void MYSQL_LOG::readers_addref()
-{
-  /* 
-    There is no necessity for reference counting on *nix, since it allows to
-    delete opened files, however it is more clean way to wait
-    untill all files will be closed on *nix as well.
-  */
-  DBUG_ENTER("MYSQL_LOG::reader_addref");
-  pthread_mutex_lock(&LOCK_log);
-  pthread_mutex_lock(&LOCK_readers);
-  readers_count++;
-  pthread_mutex_unlock(&LOCK_readers);
-  pthread_mutex_unlock(&LOCK_log);
-  DBUG_VOID_RETURN;
-}
-
-void MYSQL_LOG::readers_release()
-{
-  DBUG_ENTER("MYSQL_LOG::reader_release");
-  pthread_mutex_lock(&LOCK_log);
-  readers_count--;
-  if (!readers_count)
-    pthread_cond_broadcast(&reset_cond);
-  pthread_mutex_unlock(&LOCK_log);
-  DBUG_VOID_RETURN;
-}
-
 #ifdef __NT__
 void print_buffer_to_nt_eventlog(enum loglevel level, char *buff,
                                  uint length, int buffLen)