Don't unblock SIGQUIT in the SIGQUIT handler

petere · petere · commit d6de43099ac0 · 2009-12-16T23:05:00.000Z
This was possibly linked to a deadlock-like situation in glibc syslog code
invoked by the ereport call in quickdie().  In any case, a signal handler
should not unblock its own signal unless there is a specific reason to.
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.577 2009/12/16 22:55:33 petere Exp $
+ *	  $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.578 2009/12/16 23:05:00 petere Exp $
  *
  * NOTES
  *	  this is the "main" module of the postgres backend and
@@ -2538,6 +2538,7 @@ drop_unnamed_stmt(void)
 void
 quickdie(SIGNAL_ARGS)
 {
+	sigaddset(&BlockSig, SIGQUIT); /* prevent nested calls */
 	PG_SETMASK(&BlockSig);
 
 	/*
diff --git a/src/include/libpq/pqsignal.h b/src/include/libpq/pqsignal.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/libpq/pqsignal.h,v 1.35 2009/12/16 22:55:34 petere Exp $
+ * $PostgreSQL: pgsql/src/include/libpq/pqsignal.h,v 1.36 2009/12/16 23:05:00 petere Exp $
  *
  * NOTES
  *	  This shouldn't be in libpq, but the monitor and some other
@@ -38,6 +38,7 @@ extern int	UnBlockSig,
 int			pqsigsetmask(int mask);
 #endif
 
+#define sigaddset(set, signum)	(*(set) |= (sigmask(signum)))
 #define sigdelset(set, signum)	(*(set) &= ~(sigmask(signum)))
 #endif /* not HAVE_SIGPROCMASK */
 

Original file line number	Diff line number	Diff line change
`@@ -8,7 +8,7 @@`
`8`	`8`	`*`
`9`	`9`	`*`
`10`	`10`	`* IDENTIFICATION`
`11`		`- * $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.577 2009/12/16 22:55:33 petere Exp $`
	`11`	`+ * $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.578 2009/12/16 23:05:00 petere Exp $`
`12`	`12`	`*`
`13`	`13`	`* NOTES`
`14`	`14`	`* this is the "main" module of the postgres backend and`
`@@ -2538,6 +2538,7 @@ drop_unnamed_stmt(void)`
`2538`	`2538`	`void`
`2539`	`2539`	`quickdie(SIGNAL_ARGS)`
`2540`	`2540`	`{`
	`2541`	`+ sigaddset(&BlockSig, SIGQUIT); /* prevent nested calls */`
`2541`	`2542`	`PG_SETMASK(&BlockSig);`
`2542`	`2543`
`2543`	`2544`	`/*`
Original file line number	Diff line number	Diff line change
`@@ -7,7 +7,7 @@`
`7`	`7`	`* Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group`
`8`	`8`	`* Portions Copyright (c) 1994, Regents of the University of California`
`9`	`9`	`*`
`10`		`- * $PostgreSQL: pgsql/src/include/libpq/pqsignal.h,v 1.35 2009/12/16 22:55:34 petere Exp $`
	`10`	`+ * $PostgreSQL: pgsql/src/include/libpq/pqsignal.h,v 1.36 2009/12/16 23:05:00 petere Exp $`
`11`	`11`	`*`
`12`	`12`	`* NOTES`
`13`	`13`	`* This shouldn't be in libpq, but the monitor and some other`
`@@ -38,6 +38,7 @@ extern int UnBlockSig,`
`38`	`38`	`int pqsigsetmask(int mask);`
`39`	`39`	`#endif`
`40`	`40`
	`41`	`+#define sigaddset(set, signum) (*(set) \|= (sigmask(signum)))`
`41`	`42`	`#define sigdelset(set, signum) (*(set) &= ~(sigmask(signum)))`
`42`	`43`	`#endif /* not HAVE_SIGPROCMASK */`
`43`	`44`