From 3f0fa93cfc2442cb4952fa824525b4d7b4346db7 Mon Sep 17 00:00:00 2001
From: Bruce Momjian <bruce@momjian.us>
Date: Tue, 17 Aug 2004 16:54:47 +0000
Subject: [PATCH] Chain on to SIGPIPE handler rather than just do action on
default.
Always create thread-specific variable.
---
doc/src/sgml/libpq.sgml | 5 ++---
src/interfaces/libpq/fe-secure.c | 38 ++++++++++++++------------------
2 files changed, 19 insertions(+), 24 deletions(-)
diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index af9a35a620d..06c93306432 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -1,5 +1,5 @@
<!--
-$PostgreSQL: pgsql/doc/src/sgml/libpq.sgml,v 1.159 2004/08/16 02:12:29 tgl Exp $
+$PostgreSQL: pgsql/doc/src/sgml/libpq.sgml,v 1.160 2004/08/17 16:54:46 momjian Exp $
-->
<chapter id="libpq">
@@ -3738,8 +3738,7 @@ When <productname>PostgreSQL</> is configured without
<function>send()</> call and restores the original signal handler after
completion. When <literal>--enable-thread-safety</> is used,
<application>libpq</> installs its own <literal>SIGPIPE</> handler
-before the first database connection if no custom <literal>SIGPIPE</>
-handler has been installed previously. This handler uses thread-local
+before the first database connection. This handler uses thread-local
storage to determine if a <literal>SIGPIPE</> signal has been generated
by a libpq <function>send()</>. If an application wants to install
its own <literal>SIGPIPE</> signal handler, it should call
diff --git a/src/interfaces/libpq/fe-secure.c b/src/interfaces/libpq/fe-secure.c
index dac639c8e48..6313dc146f0 100644
--- a/src/interfaces/libpq/fe-secure.c
+++ b/src/interfaces/libpq/fe-secure.c
@@ -11,7 +11,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/interfaces/libpq/fe-secure.c,v 1.46 2004/08/17 04:24:23 tgl Exp $
+ * $PostgreSQL: pgsql/src/interfaces/libpq/fe-secure.c,v 1.47 2004/08/17 16:54:47 momjian Exp $
*
* NOTES
* The client *requires* a valid server certificate. Since
@@ -152,7 +152,8 @@ static SSL_CTX *SSL_context = NULL;
#ifdef ENABLE_THREAD_SAFETY
static void sigpipe_handler_ignore_send(int signo);
-pthread_key_t pq_thread_in_send = 0;
+pthread_key_t pq_thread_in_send = 0; /* initializer needed on Darwin */
+static pqsigfunc pq_pipe_handler;
#endif
/* ------------------------------------------------------------ */
@@ -1190,23 +1191,12 @@ PQgetssl(PGconn *conn)
void
pq_check_sigpipe_handler(void)
{
- pqsigfunc pipehandler;
-
+ pthread_key_create(&pq_thread_in_send, NULL);
/*
- * If the app hasn't set a SIGPIPE handler, define our own
- * that ignores SIGPIPE on libpq send() and does SIG_DFL
- * for other SIGPIPE cases.
+ * Find current pipe handler and chain on to it.
*/
- pipehandler = pqsignalinquire(SIGPIPE);
- if (pipehandler == SIG_DFL) /* not set by application */
- {
- /*
- * Create key first because the signal handler might be called
- * right after being installed.
- */
- pthread_key_create(&pq_thread_in_send, NULL);
- pqsignal(SIGPIPE, sigpipe_handler_ignore_send);
- }
+ pq_pipe_handler = pqsignalinquire(SIGPIPE);
+ pqsignal(SIGPIPE, sigpipe_handler_ignore_send);
}
/*
@@ -1216,12 +1206,18 @@ void
sigpipe_handler_ignore_send(int signo)
{
/*
- * If we have gotten a SIGPIPE outside send(), exit.
- * Synchronous signals are delivered to the thread
- * that caused the signal.
+ * If we have gotten a SIGPIPE outside send(), chain or
+ * exit if we are at the end of the chain.
+ * Synchronous signals are delivered to the thread that
+ * caused the signal.
*/
if (!PQinSend())
- exit(128 + SIGPIPE); /* typical return value for SIG_DFL */
+ {
+ if (pq_pipe_handler == SIG_DFL) /* not set by application */
+ exit(128 + SIGPIPE); /* typical return value for SIG_DFL */
+ else
+ (*pq_pipe_handler)(signo); /* call original handler */
+ }
}
#endif
#endif
--
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