Add CHECK_FOR_INTERRUPTS() to the repeat() function

jconway · jconway · commit 3ccae5445cc8 · 2020-05-28T13:19:10.000-04:00
The repeat() function loops for potentially a long time without ever checking for interrupts. This prevents, for example, a query cancel from interrupting until the work is all done. Fix by inserting a CHECK_FOR_INTERRUPTS() into the loop. Backpatch to all supported versions. Discussion: https://www.postgresql.org/message-id/flat/8692553c-7fe8-17d9-cbc1-7cddb758f4c6%40joeconway.com
diff --git a/src/backend/utils/adt/oracle_compat.c b/src/backend/utils/adt/oracle_compat.c
@@ -19,7 +19,7 @@
 #include "utils/builtins.h"
 #include "utils/formatting.h"
 #include "mb/pg_wchar.h"
-
+#include "miscadmin.h"
 
 static text *dotrim(const char *string, int stringlen,
 					const char *set, int setlen,
@@ -1062,6 +1062,7 @@ repeat(PG_FUNCTION_ARGS)
 	{
 		memcpy(cp, sp, slen);
 		cp += slen;
+		CHECK_FOR_INTERRUPTS();
 	}
 
 	PG_RETURN_TEXT_P(result);

Original file line number	Diff line number	Diff line change
`@@ -19,7 +19,7 @@`
`19`	`19`	`#include "utils/builtins.h"`
`20`	`20`	`#include "utils/formatting.h"`
`21`	`21`	`#include "mb/pg_wchar.h"`
`22`		`-`
	`22`	`+#include "miscadmin.h"`
`23`	`23`
`24`	`24`	`static text dotrim(const char string, int stringlen,`
`25`	`25`	`const char *set, int setlen,`
`@@ -1062,6 +1062,7 @@ repeat(PG_FUNCTION_ARGS)`
`1062`	`1062`	`{`
`1063`	`1063`	`memcpy(cp, sp, slen);`
`1064`	`1064`	`cp += slen;`
	`1065`	`+ CHECK_FOR_INTERRUPTS();`
`1065`	`1066`	`}`
`1066`	`1067`
`1067`	`1068`	`PG_RETURN_TEXT_P(result);`