Chain on to SIGPIPE handler rather than just do action on default.

Always create thread-specific variable.
This commit is contained in:
Bruce Momjian 2004-08-17 16:54:47 +00:00
parent 0d4aa039ac
commit 3f0fa93cfc
2 changed files with 19 additions and 24 deletions

View File

@ -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

View File

@ -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