InnoDB: Print more than 300 characters of queries in various error conditions,

most notably deadlocked ones in SHOW INNODB STATUS. Fixes bug #7819.


innobase/btr/btr0pcur.c:
  Adapt to changes in trx_print.
innobase/include/trx0trx.h:
  Add max_query_len parameter to trx_print.
innobase/lock/lock0lock.c:
  Adapt to changes in trx_print.
innobase/row/row0ins.c:
  Adapt to changes in trx_print.
innobase/row/row0sel.c:
  Adapt to changes in trx_print.
innobase/row/row0umod.c:
  Adapt to changes in trx_print.
innobase/row/row0upd.c:
  Adapt to changes in trx_print.
innobase/srv/srv0srv.c:
  Adapt to changes in trx_print.
innobase/trx/trx0trx.c:
  Add max_query_len parameter to trx_print.
sql/ha_innodb.cc:
  Add max_query_len parameter to innobase_mysql_print_thd.

innobase/btr/btr0pcur.c

@@ -210,7 +210,7 @@ btr_pcur_restore_position(
 			     && cursor->pos_state != BTR_PCUR_IS_POSITIONED)) {
 		ut_print_buf(stderr, (const byte*)cursor, sizeof(btr_pcur_t));
 		if (cursor->trx_if_known) {
-			trx_print(stderr, cursor->trx_if_known);
+			trx_print(stderr, cursor->trx_if_known, 0);
 		}
 		
 		ut_error;

innobase/include/trx0trx.h

@@ -329,17 +329,20 @@ trx_commit_step(
 /*============*/
 				/* out: query thread to run next, or NULL */
 	que_thr_t*	thr);	/* in: query thread */
+
 /**************************************************************************
-Prints info about a transaction to the standard output. The caller must
-own the kernel mutex and must have called
-innobase_mysql_prepare_print_arbitrary_thd(), unless he knows that MySQL or
-InnoDB cannot meanwhile change the info printed here. */
+Prints info about a transaction to the given file. The caller must own the
+kernel mutex and must have called
+innobase_mysql_prepare_print_arbitrary_thd(), unless he knows that MySQL
+or InnoDB cannot meanwhile change the info printed here. */
 
 void
 trx_print(
 /*======*/
-	FILE*	f,	/* in: output stream */
-	trx_t*	trx);	/* in: transaction */
+	FILE*	f,		/* in: output stream */
+	trx_t*	trx,		/* in: transaction */
+	uint	max_query_len);	/* in: max query length to print, or 0 to
+				   use the default max length */
 
 #ifndef UNIV_HOTBACKUP
 /**************************************************************************

innobase/lock/lock0lock.c

@@ -3297,7 +3297,7 @@ lock_deadlock_recursive(
 
 				fputs("\n*** (1) TRANSACTION:\n", ef);
 
-				trx_print(ef, wait_lock->trx);
+				trx_print(ef, wait_lock->trx, 3000);
 
 				fputs(
 			"*** (1) WAITING FOR THIS LOCK TO BE GRANTED:\n", ef);
@@ -3310,7 +3310,7 @@ lock_deadlock_recursive(
 			
 				fputs("*** (2) TRANSACTION:\n", ef);
 
-				trx_print(ef, lock->trx);
+				trx_print(ef, lock->trx, 3000);
 
 				fputs("*** (2) HOLDS THE LOCK(S):\n", ef);
 			
@@ -4207,7 +4207,7 @@ lock_print_info_all_transactions(
 	while (trx) {
 		if (trx->conc_state == TRX_NOT_STARTED) {
 			fputs("---", file);
-			trx_print(file, trx);
+			trx_print(file, trx, 600);
 		}
 			
 		trx = UT_LIST_GET_NEXT(mysql_trx_list, trx);
@@ -4239,7 +4239,7 @@ lock_print_info_all_transactions(
 
 	if (nth_lock == 0) {
 		fputs("---", file);
-		trx_print(file, trx);
+		trx_print(file, trx, 600);
 		
 	        if (trx->read_view) {
 			fprintf(file,

innobase/row/row0ins.c

@@ -602,7 +602,7 @@ row_ins_foreign_report_err(
 	rewind(ef);
 	ut_print_timestamp(ef);
 	fputs(" Transaction:\n", ef);
-	trx_print(ef, trx);
+	trx_print(ef, trx, 600);
 
 	fputs("Foreign key constraint fails for table ", ef);
 	ut_print_name(ef, trx, foreign->foreign_table_name);
@@ -653,7 +653,7 @@ row_ins_foreign_report_add_err(
 	rewind(ef);
 	ut_print_timestamp(ef);
 	fputs(" Transaction:\n", ef);
-	trx_print(ef, trx);
+	trx_print(ef, trx, 600);
 	fputs("Foreign key constraint fails for table ", ef);
 	ut_print_name(ef, trx, foreign->foreign_table_name);
 	fputs(":\n", ef);
@@ -1228,7 +1228,7 @@ row_ins_check_foreign_constraint(
 			rewind(ef);
 			ut_print_timestamp(ef);
 			fputs(" Transaction:\n", ef);
-			trx_print(ef, trx);
+			trx_print(ef, trx, 600);
 			fputs("Foreign key constraint fails for table ", ef);
 			ut_print_name(ef, trx, foreign->foreign_table_name);
 			fputs(":\n", ef);

innobase/row/row0sel.c

@@ -2685,7 +2685,7 @@ row_sel_get_clust_rec_for_mysql(
 				"InnoDB: clust index record ", stderr);
 			rec_print(stderr, clust_rec, clust_index);
 			putc('\n', stderr);
-			trx_print(stderr, trx);
+			trx_print(stderr, trx, 600);
 
 			fputs("\n"
 "InnoDB: Submit a detailed bug report to http://bugs.mysql.com\n", stderr);
@@ -3128,7 +3128,7 @@ row_search_for_mysql(
 "InnoDB: Error: MySQL is trying to perform a SELECT\n"
 "InnoDB: but it has not locked any tables in ::external_lock()!\n",
                       stderr);
-		trx_print(stderr, trx);
+		trx_print(stderr, trx, 600);
                 fputc('\n', stderr);
 	}
 
@@ -3455,7 +3455,7 @@ row_search_for_mysql(
 			fputs(
 "InnoDB: Error: MySQL is trying to perform a consistent read\n"
 "InnoDB: but the read view is not assigned!\n", stderr);
-			trx_print(stderr, trx);
+			trx_print(stderr, trx, 600);
                         fputc('\n', stderr);
 			ut_a(0);
 		}

innobase/row/row0umod.c

@@ -431,7 +431,7 @@ row_undo_mod_del_unmark_sec_and_undo_update(
 			"InnoDB: record ", stderr);
 		rec_print(stderr, btr_pcur_get_rec(&pcur), index);
 		putc('\n', stderr);
-		trx_print(stderr, trx);
+		trx_print(stderr, trx, 0);
 		fputs("\n"
 "InnoDB: Submit a detailed bug report to http://bugs.mysql.com\n", stderr);
 	} else {

innobase/row/row0upd.c

@@ -1279,7 +1279,7 @@ row_upd_sec_index_entry(
 		rec_print(stderr, rec, index);
 		putc('\n', stderr);
 
-		trx_print(stderr, trx);
+		trx_print(stderr, trx, 0);
 
 		fputs("\n"
 "InnoDB: Submit a detailed bug report to http://bugs.mysql.com\n", stderr);

innobase/srv/srv0srv.c

@@ -999,7 +999,7 @@ srv_conc_enter_innodb(
 		fputs(
 "  InnoDB: Error: trying to declare trx to enter InnoDB, but\n"
 "InnoDB: it already is declared.\n", stderr);
-		trx_print(stderr, trx);
+		trx_print(stderr, trx, 0);
 		putc('\n', stderr);
 		os_fast_mutex_unlock(&srv_conc_mutex);
 

innobase/trx/trx0trx.c

@@ -30,8 +30,9 @@ Created 3/26/1996 Heikki Tuuri
 copy MUST be equal to the one in mysql/sql/ha_innodb.cc ! */
 
 void innobase_mysql_print_thd(
-	FILE* f,
-	void* thd);
+	FILE*	f,
+	void*	thd,
+	uint	max_query_len);
 
 /* Dummy session used currently in MySQL interface */
 sess_t*		trx_dummy_sess = NULL;
@@ -262,7 +263,7 @@ trx_free(
 		fputs(
 "  InnoDB: Error: Freeing a trx which is declared to be processing\n"
 "InnoDB: inside InnoDB.\n", stderr);
-		trx_print(stderr, trx);
+		trx_print(stderr, trx, 600);
 		putc('\n', stderr);
 	}
 
@@ -277,7 +278,7 @@ trx_free(
 			(ulong)trx->n_mysql_tables_in_use,
 			(ulong)trx->mysql_n_tables_locked);
 
-		trx_print(stderr, trx);		
+		trx_print(stderr, trx, 600);
 
 		ut_print_buf(stderr, (byte*)trx, sizeof(trx_t));
 	}
@@ -1651,16 +1652,18 @@ trx_mark_sql_stat_end(
 }
 
 /**************************************************************************
-Prints info about a transaction to the standard output. The caller must
-own the kernel mutex and must have called
-innobase_mysql_prepare_print_arbitrary_thd(), unless he knows that MySQL or
-InnoDB cannot meanwhile change the info printed here. */
+Prints info about a transaction to the given file. The caller must own the
+kernel mutex and must have called
+innobase_mysql_prepare_print_arbitrary_thd(), unless he knows that MySQL
+or InnoDB cannot meanwhile change the info printed here. */
 
 void
 trx_print(
 /*======*/
-	FILE*	f,	/* in: output stream */
-	trx_t*	trx)	/* in: transaction */
+	FILE*	f,		/* in: output stream */
+	trx_t*	trx,		/* in: transaction */
+	uint	max_query_len)	/* in: max query length to print, or 0 to
+				   use the default max length */
 {
 	ibool	newline;
 
@@ -1755,7 +1758,7 @@ trx_print(
 	}
 
   	if (trx->mysql_thd != NULL) {
-		innobase_mysql_print_thd(f, trx->mysql_thd);
+		innobase_mysql_print_thd(f, trx->mysql_thd, max_query_len);
   	}  
 }
 

sql/ha_innodb.cc

@@ -550,19 +550,20 @@ innobase_mysql_end_print_arbitrary_thd(void)
 }
 
 /*****************************************************************
-Prints info of a THD object (== user session thread) to the
-standard output. NOTE that /mysql/innobase/trx/trx0trx.c must contain
-the prototype for this function! */
+Prints info of a THD object (== user session thread) to the given file.
+NOTE that /mysql/innobase/trx/trx0trx.c must contain the prototype for
+this function! */
 extern "C"
 void
 innobase_mysql_print_thd(
 /*=====================*/
-	FILE*   f,	/* in: output stream */
-        void*   input_thd)/* in: pointer to a MySQL THD object */
+	FILE*   f,		/* in: output stream */
+	void*   input_thd,	/* in: pointer to a MySQL THD object */
+	uint	max_query_len)	/* in: max query length to print, or 0 to
+				   use the default max length */
 {
 	const THD*	thd;
 	const char*	s;
-	char		buf[301];
 
         thd = (const THD*) input_thd;
 
@@ -589,25 +590,47 @@ innobase_mysql_print_thd(
 	}
 
 	if ((s = thd->query)) {
-		/* determine the length of the query string */
-		uint32 i, len;
+		/* 3100 is chosen because currently 3000 is the maximum
+		   max_query_len we ever give this. */
+		char	buf[3100];
+		uint	len;
+
+		/* If buf is too small, we dynamically allocate storage
+		   in this. */
+		char*	dyn_str = NULL;
+
+		/* Points to buf or dyn_str. */
+		char*	str = buf;
 		
-		len = thd->query_length;
-
-		if (len > 300) {
-			len = 300;	/* ADDITIONAL SAFETY: print at most
-					300 chars to reduce the probability of
-					a seg fault if there is a race in
-					thd->query_length in MySQL; after
-					May 14, 2004 probably no race any more,
-					but better be safe */
+		if (max_query_len == 0)
+		{
+			/* ADDITIONAL SAFETY: the default is to print at
+			   most 300 chars to reduce the probability of a
+			   seg fault if there is a race in
+			   thd->query_length in MySQL; after May 14, 2004
+			   probably no race any more, but better be
+			   safe */
+			max_query_len = 300;
 		}
+		
+		len = min(thd->query_length, max_query_len);
 
-                /* Use strmake to reduce the timeframe
-                   for a race, compared to fwrite() */
-		i= (uint) (strmake(buf, s, len) - buf);
+		if (len > (sizeof(buf) - 1))
+		{
+			dyn_str = my_malloc(len + 1, MYF(0));
+			str = dyn_str;
+		}
+
+                /* Use strmake to reduce the timeframe for a race,
+                   compared to fwrite() */
+		len = (uint) (strmake(str, s, len) - str);
 		putc('\n', f);
-		fwrite(buf, 1, i, f);
+		fwrite(str, 1, len, f);
+
+		if (dyn_str)
+		{
+			my_free(dyn_str, MYF(0));
+		}
 	}
 
 	putc('\n', f);