improvements for stopping the slave in SLAVE STOP and on shutdown

sql/mini_client.cc:
  alarm around mc_mysql_connect()
sql/mysqld.cc:
  move end_slave() to the earlier part of shutdown
sql/sql_repl.cc:
  retry thr_alarm_kill() in case slave thread missed the signal in SLAVE STOP

sql/mini_client.cc

@@ -39,6 +39,8 @@
 #include "errmsg.h"
 #include <violite.h>
 
+extern ulong net_read_timeout;
+
 extern "C" {					// Because of SCO 3.2V4.2
 #include <sys/stat.h>
 #include <signal.h>
@@ -62,6 +64,7 @@ extern "C" {					// Because of SCO 3.2V4.2
 #endif
 #if defined(THREAD) && !defined(__WIN__)
 #include <my_pthread.h>				/* because of signal()	*/
+#include <thr_alarm.h>
 #endif
 #ifndef INADDR_NONE
 #define INADDR_NONE	-1
@@ -479,18 +482,25 @@ mc_mysql_connect(MYSQL *mysql,const char *host, const char *user,
   struct	sockaddr_in sock_addr;
   uint		pkt_length;
   NET		*net= &mysql->net;
+  thr_alarm_t   alarmed;
+#if !defined(__WIN__)
+  ALARM alarm_buff;
+#endif
+
 #ifdef __WIN__
   HANDLE	hPipe=INVALID_HANDLE_VALUE;
 #endif
 #ifdef HAVE_SYS_UN_H
   struct	sockaddr_un UNIXaddr;
 #endif
-  DBUG_ENTER("mysql_real_connect");
+  DBUG_ENTER("mc_mysql_connect");
 
   DBUG_PRINT("enter",("host: %s  db: %s  user: %s",
 		      host ? host : "(Null)",
 		      db ? db : "(Null)",
 		      user ? user : "(Null)"));
+  thr_alarm_init(&alarmed);
+  thr_alarm(&alarmed,(uint) net_read_timeout,&alarm_buff);
 
   bzero((char*) &mysql->options,sizeof(mysql->options));
   net->vio = 0;				/* If something goes wrong */
@@ -625,8 +635,12 @@ mc_mysql_connect(MYSQL *mysql,const char *host, const char *user,
       DBUG_PRINT("error",("Got error %d on connect to '%s'",ERRNO,host));
       net->last_errno= CR_CONN_HOST_ERROR;
       sprintf(net->last_error ,ER(CR_CONN_HOST_ERROR), host, ERRNO);
+      if (thr_alarm_in_use(&alarmed))
+	thr_end_alarm(&alarmed);
       goto error;
     }
+    if (thr_alarm_in_use(&alarmed))
+      thr_end_alarm(&alarmed);
   }
 
   if (!net->vio || my_net_init(net, net->vio))

sql/mysqld.cc

@@ -487,6 +487,7 @@ static void close_connections(void)
   }
 #endif
   end_thr_alarm();			 // Don't allow alarms
+  end_slave();
 
   /* First signal all threads that it's time to die */
 
@@ -694,7 +695,6 @@ void clean_up(bool print_message)
   x_free(opt_bin_logname);
   bitmap_free(&temp_pool);
   free_max_user_conn();
-  end_slave();
 #ifndef __WIN__
   if (!opt_bootstrap)
     (void) my_delete(pidfile_name,MYF(0));	// This may not always exist

sql/sql_repl.cc

@@ -610,8 +610,26 @@ int stop_slave(THD* thd, bool net_report )
     // do not abort the slave in the middle of a query, so we do not set
     // thd->killed for the slave thread
     thd->proc_info = "waiting for slave to die";
-    while(slave_running) 
-      pthread_cond_wait(&COND_slave_stopped, &LOCK_slave);
+    while(slave_running)
+    {
+      /* there is a small change that slave thread might miss the first
+	 alarm. To protect againts it, resend the signal until it reacts
+      */
+	 
+      struct timespec abstime;
+#ifdef HAVE_TIMESPEC_TS_SEC
+      abstime.ts_sec=time(NULL)+2;		
+      abstime.ts_nsec=0;
+#else
+      struct timeval tv;
+      gettimeofday(&tv,0);
+      abstime.tv_sec=tv.tv_sec+2;
+      abstime.tv_nsec=tv.tv_usec*1000;
+#endif
+      pthread_cond_timedwait(&COND_slave_stopped, &LOCK_slave, &abstime);
+      if (slave_running)
+        thr_alarm_kill(slave_real_id);
+    }
   }
   else
     slave_errno = ER_SLAVE_NOT_RUNNING;