Add CHECK_FOR_INTERRUPTS() to the repeat() function

jconway · jconway · commit 2cbe3a954219 · 2020-05-28T13:17:11.000-04:00
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
@@ -18,7 +18,7 @@
 #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,
@@ -1068,6 +1068,7 @@ 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
`@@ -18,7 +18,7 @@`
`18`	`18`	`#include "utils/builtins.h"`
`19`	`19`	`#include "utils/formatting.h"`
`20`	`20`	`#include "mb/pg_wchar.h"`
`21`		`-`
	`21`	`+#include "miscadmin.h"`
`22`	`22`
`23`	`23`	`static text dotrim(const char string, int stringlen,`
`24`	`24`	`const char *set, int setlen,`
`@@ -1068,6 +1068,7 @@ repeat(PG_FUNCTION_ARGS)`
`1068`	`1068`	`{`
`1069`	`1069`	`memcpy(cp, sp, slen);`
`1070`	`1070`	`cp += slen;`
	`1071`	`+ CHECK_FOR_INTERRUPTS();`
`1071`	`1072`	`}`
`1072`	`1073`
`1073`	`1074`	`PG_RETURN_TEXT_P(result);`