mc/slang/slsignal.c

337 lines
6.5 KiB
C

/* Copyright (c) 1998, 1999, 2001, 2002 John E. Davis
* This file is part of the S-Lang library.
*
* You may distribute under the terms of either the GNU General Public
* License or the Perl Artistic License.
*/
#include "slinclud.h"
#include <signal.h>
#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif
#ifdef HAVE_SYS_WAIT_H
# include <sys/wait.h>
#endif
#include <errno.h>
#include "slang.h"
#include "_slang.h"
/* Do not trust these environments */
#if defined(__CYGWIN32__) || defined(__MINGW32__) || defined(AMIGA)
# ifdef SLANG_POSIX_SIGNALS
# undef SLANG_POSIX_SIGNALS
# endif
#endif
/* This function will cause system calls to be restarted after signal if possible */
SLSig_Fun_Type *SLsignal (int sig, SLSig_Fun_Type *f)
{
#if defined(SLANG_POSIX_SIGNALS)
struct sigaction old_sa, new_sa;
# ifdef SIGALRM
/* We want system calls to be interrupted by SIGALRM. */
if (sig == SIGALRM) return SLsignal_intr (sig, f);
# endif
sigemptyset (&new_sa.sa_mask);
new_sa.sa_handler = f;
new_sa.sa_flags = 0;
# ifdef SA_RESTART
new_sa.sa_flags |= SA_RESTART;
# endif
if (-1 == sigaction (sig, &new_sa, &old_sa))
return (SLSig_Fun_Type *) SIG_ERR;
return old_sa.sa_handler;
#else
/* Not POSIX. */
return signal (sig, f);
#endif
}
/* This function will NOT cause system calls to be restarted after
* signal if possible
*/
SLSig_Fun_Type *SLsignal_intr (int sig, SLSig_Fun_Type *f)
{
#ifdef SLANG_POSIX_SIGNALS
struct sigaction old_sa, new_sa;
sigemptyset (&new_sa.sa_mask);
new_sa.sa_handler = f;
new_sa.sa_flags = 0;
# ifdef SA_INTERRUPT
new_sa.sa_flags |= SA_INTERRUPT;
# endif
if (-1 == sigaction (sig, &new_sa, &old_sa))
return (SLSig_Fun_Type *) SIG_ERR;
return old_sa.sa_handler;
#else
/* Not POSIX. */
return signal (sig, f);
#endif
}
/* We are primarily interested in blocking signals that would cause the
* application to reset the tty. These include suspend signals and
* possibly interrupt signals.
*/
#ifdef SLANG_POSIX_SIGNALS
static sigset_t Old_Signal_Mask;
#endif
static volatile unsigned int Blocked_Depth;
int SLsig_block_signals (void)
{
#ifdef SLANG_POSIX_SIGNALS
sigset_t new_mask;
#endif
Blocked_Depth++;
if (Blocked_Depth != 1)
{
return 0;
}
#ifdef SLANG_POSIX_SIGNALS
sigemptyset (&new_mask);
# ifdef SIGQUIT
sigaddset (&new_mask, SIGQUIT);
# endif
# ifdef SIGTSTP
sigaddset (&new_mask, SIGTSTP);
# endif
# ifdef SIGINT
sigaddset (&new_mask, SIGINT);
# endif
# ifdef SIGTTIN
sigaddset (&new_mask, SIGTTIN);
# endif
# ifdef SIGTTOU
sigaddset (&new_mask, SIGTTOU);
# endif
# ifdef SIGWINCH
sigaddset (&new_mask, SIGWINCH);
# endif
(void) sigprocmask (SIG_BLOCK, &new_mask, &Old_Signal_Mask);
return 0;
#else
/* Not implemented. */
return -1;
#endif
}
int SLsig_unblock_signals (void)
{
if (Blocked_Depth == 0)
return -1;
Blocked_Depth--;
if (Blocked_Depth != 0)
return 0;
#ifdef SLANG_POSIX_SIGNALS
(void) sigprocmask (SIG_SETMASK, &Old_Signal_Mask, NULL);
return 0;
#else
return -1;
#endif
}
#if 0
#ifdef MSWINDOWS
int SLsystem (char *cmd)
{
SLang_verror (SL_NOT_IMPLEMENTED, "system not implemented");
return -1;
}
#else
int SLsystem (char *cmd)
{
#ifdef SLANG_POSIX_SIGNALS
pid_t pid;
int status;
struct sigaction ignore;
# ifdef SIGINT
struct sigaction save_intr;
# endif
# ifdef SIGQUIT
struct sigaction save_quit;
# endif
# ifdef SIGCHLD
sigset_t child_mask, save_mask;
# endif
if (cmd == NULL) return 1;
ignore.sa_handler = SIG_IGN;
sigemptyset (&ignore.sa_mask);
ignore.sa_flags = 0;
# ifdef SIGINT
if (-1 == sigaction (SIGINT, &ignore, &save_intr))
return -1;
# endif
# ifdef SIGQUIT
if (-1 == sigaction (SIGQUIT, &ignore, &save_quit))
{
(void) sigaction (SIGINT, &save_intr, NULL);
return -1;
}
# endif
# ifdef SIGCHLD
sigemptyset (&child_mask);
sigaddset (&child_mask, SIGCHLD);
if (-1 == sigprocmask (SIG_BLOCK, &child_mask, &save_mask))
{
# ifdef SIGINT
(void) sigaction (SIGINT, &save_intr, NULL);
# endif
# ifdef SIGQUIT
(void) sigaction (SIGQUIT, &save_quit, NULL);
# endif
return -1;
}
# endif
pid = fork();
if (pid == -1)
status = -1;
else if (pid == 0)
{
/* Child */
# ifdef SIGINT
(void) sigaction (SIGINT, &save_intr, NULL);
# endif
# ifdef SIGQUIT
(void) sigaction (SIGQUIT, &save_quit, NULL);
# endif
# ifdef SIGCHLD
(void) sigprocmask (SIG_SETMASK, &save_mask, NULL);
# endif
execl ("/bin/sh", "sh", "-c", cmd, (char *) NULL);
_exit (127);
}
else
{
/* parent */
while (-1 == waitpid (pid, &status, 0))
{
# ifdef EINTR
if (errno == EINTR)
continue;
# endif
# ifdef ERESTARTSYS
if (errno == ERESTARTSYS)
continue;
# endif
status = -1;
break;
}
}
# ifdef SIGINT
if (-1 == sigaction (SIGINT, &save_intr, NULL))
status = -1;
# endif
# ifdef SIGQUIT
if (-1 == sigaction (SIGQUIT, &save_quit, NULL))
status = -1;
# endif
# ifdef SIGCHLD
if (-1 == sigprocmask (SIG_SETMASK, &save_mask, NULL))
status = -1;
# endif
return status;
#else /* No POSIX Signals */
# ifdef SIGINT
void (*sint)(int);
# endif
# ifdef SIGQUIT
void (*squit)(int);
# endif
int status;
# ifdef SIGQUIT
squit = SLsignal (SIGQUIT, SIG_IGN);
# endif
# ifdef SIGINT
sint = SLsignal (SIGINT, SIG_IGN);
# endif
status = system (cmd);
# ifdef SIGINT
SLsignal (SIGINT, sint);
# endif
# ifdef SIGQUIT
SLsignal (SIGQUIT, squit);
# endif
return status;
#endif /* POSIX_SIGNALS */
}
#endif
#include <windows.h>
static int msw_system (char *cmd)
{
STARTUPINFO startup_info;
PROCESS_INFORMATION process_info;
int status;
if (cmd == NULL) return -1;
memset ((char *) &startup_info, 0, sizeof (STARTUPINFO));
startup_info.cb = sizeof(STARTUPINFO);
startup_info.dwFlags = STARTF_USESHOWWINDOW;
startup_info.wShowWindow = SW_SHOWDEFAULT;
if (FALSE == CreateProcess (NULL,
cmd,
NULL,
NULL,
FALSE,
NORMAL_PRIORITY_CLASS|CREATE_NEW_CONSOLE,
NULL,
NULL,
&startup_info,
&process_info))
{
SLang_verror (0, "%s: CreateProcess failed.", cmd);
return -1;
}
status = -1;
if (0xFFFFFFFFUL != WaitForSingleObject (process_info.hProcess, INFINITE))
{
DWORD exit_code;
if (TRUE == GetExitCodeProcess (process_info.hProcess, &exit_code))
status = (int) exit_code;
}
CloseHandle (process_info.hThread);
CloseHandle (process_info.hProcess);
return status;
}
#endif