A fix (bug #5382: Server crashes after writing INTO OUTFILE)

mysql-test/r/outfile.result

+drop table if exists t1;
+CREATE TABLE t1 (a INT);
+EXPLAIN 
+SELECT *
+INTO OUTFILE '/tmp/t1.txt'
+  FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' LINES TERMINATED BY '\r\n'
+  FROM t1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	system	NULL	NULL	NULL	NULL	0	const row not found
+DROP TABLE t1;

mysql-test/t/outfile.test

@@ -2,6 +2,10 @@
 # test of into outfile|dumpfile
 #
 
+--disable_warnings
+drop table if exists t1;
+--enable_warnings
+
 # We need to check that we have 'file' privilege.
 
 #drop table if exists t1;
@@ -26,3 +30,15 @@
 #INSERT INTO t VALUES ('2002-12-20 12:01:20','',1,"aaa","bbb");
 #select * from t into outfile "check";
 #drop table if exists t;
+
+#
+# Bug #5382: 'explain select into outfile' crashes the server
+#
+
+CREATE TABLE t1 (a INT);
+EXPLAIN 
+  SELECT *
+  INTO OUTFILE '/tmp/t1.txt'
+  FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' LINES TERMINATED BY '\r\n'
+  FROM t1;
+DROP TABLE t1;

sql/sql_yacc.yy

@@ -3870,15 +3870,11 @@ select_var_ident:  '@' ident_or_text
 into:
         INTO OUTFILE TEXT_STRING_sys
 	{
-	  LEX *lex=Lex;
-	  if (!lex->describe)
-	  {
-	    lex->uncacheable(UNCACHEABLE_SIDEEFFECT);
-	    if (!(lex->exchange= new sql_exchange($3.str,0)))
-	      YYABORT;
-	    if (!(lex->result= new select_export(lex->exchange)))
-	      YYABORT;
-	  }
+	  LEX *lex= Lex;
+          lex->uncacheable(UNCACHEABLE_SIDEEFFECT);
+          if (!(lex->exchange= new sql_exchange($3.str, 0)) ||
+              !(lex->result= new select_export(lex->exchange)))
+            YYABORT;
 	}
 	opt_field_term opt_line_term
 	| INTO DUMPFILE TEXT_STRING_sys
@@ -4721,15 +4717,28 @@ field_term_list:
 	| field_term;
 
 field_term:
-	TERMINATED BY text_string { Lex->exchange->field_term= $3;}
+	TERMINATED BY text_string 
+          {
+            DBUG_ASSERT(Lex->exchange);
+            Lex->exchange->field_term= $3;
+          }
 	| OPTIONALLY ENCLOSED BY text_string
 	  {
-	    LEX *lex=Lex;
+	    LEX *lex= Lex;
+            DBUG_ASSERT(lex->exchange);
 	    lex->exchange->enclosed= $4;
-	    lex->exchange->opt_enclosed=1;
+	    lex->exchange->opt_enclosed= 1;
 	  }
-	| ENCLOSED BY text_string { Lex->exchange->enclosed= $3;}
-	| ESCAPED BY text_string  { Lex->exchange->escaped= $3;};
+	| ENCLOSED BY text_string
+          {
+            DBUG_ASSERT(Lex->exchange);
+            Lex->exchange->enclosed= $3;
+          }
+	| ESCAPED BY text_string
+          {
+            DBUG_ASSERT(Lex->exchange);
+            Lex->exchange->escaped= $3;
+          };
 
 opt_line_term:
 	/* empty */
@@ -4740,13 +4749,24 @@ line_term_list:
 	| line_term;
 
 line_term:
-	TERMINATED BY text_string { Lex->exchange->line_term= $3;}
-	| STARTING BY text_string { Lex->exchange->line_start= $3;};
+	TERMINATED BY text_string
+          {
+            DBUG_ASSERT(Lex->exchange);
+            Lex->exchange->line_term= $3;
+          }
+	| STARTING BY text_string
+          {
+            DBUG_ASSERT(Lex->exchange);
+            Lex->exchange->line_start= $3;
+          };
 
 opt_ignore_lines:
 	/* empty */
 	| IGNORE_SYM NUM LINES
-	  { Lex->exchange->skip_lines=atol($2.str); };
+	  {
+            DBUG_ASSERT(Lex->exchange);
+            Lex->exchange->skip_lines= atol($2.str);
+          };
 
 /* Common definitions */