1996-07-09 08:22:35 +02:00
|
|
|
/*-------------------------------------------------------------------------
|
|
|
|
*
|
|
|
|
* pqsignal.c--
|
|
|
|
* reliable BSD-style signal(2) routine stolen from RWW who stole it
|
|
|
|
* from Stevens...
|
|
|
|
*
|
|
|
|
* Copyright (c) 1994, Regents of the University of California
|
|
|
|
*
|
|
|
|
*
|
|
|
|
* IDENTIFICATION
|
1996-12-26 23:08:34 +01:00
|
|
|
* $Header: /cvsroot/pgsql/src/backend/libpq/pqsignal.c,v 1.5 1996/12/26 22:07:08 momjian Exp $
|
1996-07-09 08:22:35 +02:00
|
|
|
*
|
|
|
|
* NOTES
|
|
|
|
* This shouldn't be in libpq, but the monitor and some other
|
|
|
|
* things need it...
|
|
|
|
*
|
1996-11-18 03:25:09 +01:00
|
|
|
* A NOTE ABOUT SIGNAL HANDLING ACROSS THE VARIOUS PLATFORMS.
|
|
|
|
*
|
|
|
|
* config.h defines the macro USE_POSIX_SIGNALS for some platforms and
|
|
|
|
* not for others. This file and pqsignal.h use that macro to decide
|
|
|
|
* how to handle signalling.
|
|
|
|
*
|
|
|
|
* signal(2) handling - this is here because it affects some of
|
|
|
|
* the frontend commands as well as the backend server.
|
|
|
|
*
|
|
|
|
* Ultrix and SunOS provide BSD signal(2) semantics by default.
|
|
|
|
*
|
|
|
|
* SVID2 and POSIX signal(2) semantics differ from BSD signal(2)
|
|
|
|
* semantics. We can use the POSIX sigaction(2) on systems that
|
|
|
|
* allow us to request restartable signals (SA_RESTART).
|
|
|
|
*
|
|
|
|
* Some systems don't allow restartable signals at all unless we
|
|
|
|
* link to a special BSD library.
|
|
|
|
*
|
|
|
|
* We devoutly hope that there aren't any systems that provide
|
|
|
|
* neither POSIX signals nor BSD signals. The alternative
|
|
|
|
* is to do signal-handler reinstallation, which doesn't work well
|
|
|
|
* at all.
|
|
|
|
* ------------------------------------------------------------------------*/
|
1996-11-06 09:48:33 +01:00
|
|
|
#include <postgres.h>
|
1996-11-03 07:54:38 +01:00
|
|
|
|
1996-12-26 23:08:34 +01:00
|
|
|
#include <signal.h>
|
|
|
|
|
1996-11-06 09:48:33 +01:00
|
|
|
#include <libpq/pqsignal.h>
|
1996-07-09 08:22:35 +02:00
|
|
|
|
|
|
|
pqsigfunc
|
|
|
|
pqsignal(int signo, pqsigfunc func)
|
|
|
|
{
|
1996-12-26 23:08:34 +01:00
|
|
|
#if !defined(USE_POSIX_SIGNALS)
|
|
|
|
return signal(signo, func);
|
|
|
|
#else
|
1996-07-09 08:22:35 +02:00
|
|
|
struct sigaction act, oact;
|
|
|
|
|
|
|
|
act.sa_handler = func;
|
|
|
|
sigemptyset(&act.sa_mask);
|
|
|
|
act.sa_flags = 0;
|
|
|
|
if (signo != SIGALRM) {
|
|
|
|
act.sa_flags |= SA_RESTART;
|
|
|
|
}
|
|
|
|
if (sigaction(signo, &act, &oact) < 0)
|
|
|
|
return(SIG_ERR);
|
|
|
|
return(oact.sa_handler);
|
|
|
|
#endif /* !USE_POSIX_SIGNALS */
|
|
|
|
}
|