cosmopolitan/third_party/python/Python/getsig.c
Justine Tunney adac64a52b Reduce makefile dependencies by 10%
The includes in libc/calls/calls.h have now been refactored so that
functions with struct parameters are declared in libc/calls/struct/
2022-06-08 20:01:28 -07:00

76 lines
2.7 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=4 sts=4 sw=4 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Python 3 │
│ https://docs.python.org/3/license.html │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/calls/struct/sigaction.h"
#include "third_party/python/Include/pydebug.h"
#include "third_party/python/Include/pylifecycle.h"
#include "third_party/python/pyconfig.h"
/* clang-format off */
PyOS_sighandler_t
PyOS_getsig(int sig)
{
#ifdef HAVE_SIGACTION
struct sigaction context;
if (sigaction(sig, NULL, &context) == -1)
return SIG_ERR;
return context.sa_handler;
#else
PyOS_sighandler_t handler;
/* Special signal handling for the secure CRT in Visual Studio 2005 */
#if defined(_MSC_VER) && _MSC_VER >= 1400
switch (sig) {
/* Only these signals are valid */
case SIGINT:
case SIGILL:
case SIGFPE:
case SIGSEGV:
case SIGTERM:
case SIGBREAK:
case SIGABRT:
break;
/* Don't call signal() with other values or it will assert */
default:
return SIG_ERR;
}
#endif /* _MSC_VER && _MSC_VER >= 1400 */
handler = signal(sig, SIG_IGN);
if (handler != SIG_ERR)
signal(sig, handler);
return handler;
#endif
}
/*
* All of the code in this function must only use async-signal-safe functions,
* listed at `man 7 signal` or
* http://www.opengroup.org/onlinepubs/009695399/functions/xsh_chap02_04.html.
*/
PyOS_sighandler_t
PyOS_setsig(int sig, PyOS_sighandler_t handler)
{
#ifdef HAVE_SIGACTION
/* Some code in Modules/signalmodule.c depends on sigaction() being
* used here if HAVE_SIGACTION is defined. Fix that if this code
* changes to invalidate that assumption.
*/
struct sigaction context, ocontext;
context.sa_handler = handler;
sigemptyset(&context.sa_mask);
context.sa_flags = 0;
if (sigaction(sig, &context, &ocontext) == -1)
return SIG_ERR;
return ocontext.sa_handler;
#else
PyOS_sighandler_t oldhandler;
oldhandler = signal(sig, handler);
#ifdef HAVE_SIGINTERRUPT
siginterrupt(sig, 1);
#endif
return oldhandler;
#endif
}