/* Interfaces to system-dependent kernel and library entries.
- Copyright (C) 1985-1988, 1993-1995, 1999-2012
- Free Software Foundation, Inc.
+ Copyright (C) 1985-1988, 1993-1995, 1999-2013 Free Software
+ Foundation, Inc.
This file is part of GNU Emacs.
#define SYSTIME_INLINE EXTERN_INLINE
#include <execinfo.h>
-#include <stdio.h>
+#include "sysstdio.h"
#ifdef HAVE_PWD_H
#include <pwd.h>
#include <grp.h>
#include <limits.h>
#include <unistd.h>
-#include <allocator.h>
#include <c-ctype.h>
-#include <careadlinkat.h>
#include <ignore-value.h>
#include <utimens.h>
#include "sysselect.h"
#include "blockinput.h"
-#ifdef BSD_SYSTEM
-#include <sys/param.h>
-#include <sys/sysctl.h>
+#if defined DARWIN_OS || defined __FreeBSD__
+# include <sys/sysctl.h>
#endif
#ifdef __FreeBSD__
#ifdef MSDOS /* Demacs 1.1.2 91/10/20 Manabu Higashida, MW Aug 1993 */
#include "msdos.h"
-#include <sys/param.h>
#endif
+#include <sys/param.h>
#include <sys/file.h>
#include <fcntl.h>
#ifndef MSDOS
-static void
-wait_for_termination_1 (pid_t pid, int interruptible)
+/* Wait for the subprocess with process id CHILD to terminate or change status.
+ CHILD must be a child process that has not been reaped.
+ If STATUS is non-null, store the waitpid-style exit status into *STATUS
+ and tell wait_reading_process_output that it needs to look around.
+ Use waitpid-style OPTIONS when waiting.
+ If INTERRUPTIBLE, this function is interruptible by a signal.
+
+ Return CHILD if successful, 0 if no status is available;
+ the latter is possible only when options & NOHANG. */
+static pid_t
+get_child_status (pid_t child, int *status, int options, bool interruptible)
{
- while (1)
+ pid_t pid;
+
+ /* Invoke waitpid only with a known process ID; do not invoke
+ waitpid with a nonpositive argument. Otherwise, Emacs might
+ reap an unwanted process by mistake. For example, invoking
+ waitpid (-1, ...) can mess up glib by reaping glib's subprocesses,
+ so that another thread running glib won't find them. */
+ eassert (child > 0);
+
+ while ((pid = waitpid (child, status, options)) < 0)
{
- int status;
- int wait_result = waitpid (pid, &status, 0);
- if (wait_result < 0)
- {
- if (errno != EINTR)
- break;
- }
- else
- {
- record_child_status_change (wait_result, status);
- break;
- }
+ /* Check that CHILD is a child process that has not been reaped,
+ and that STATUS and OPTIONS are valid. Otherwise abort,
+ as continuing after this internal error could cause Emacs to
+ become confused and kill innocent-victim processes. */
+ if (errno != EINTR)
+ emacs_abort ();
/* Note: the MS-Windows emulation of waitpid calls QUIT
internally. */
if (interruptible)
QUIT;
}
-}
-/* Wait for subprocess with process id `pid' to terminate and
- make sure it will get eliminated (not remain forever as a zombie) */
+ /* If successful and status is requested, tell wait_reading_process_output
+ that it needs to wake up and look around. */
+ if (pid && status && input_available_clear_time)
+ *input_available_clear_time = make_emacs_time (0, 0);
+ return pid;
+}
+
+/* Wait for the subprocess with process id CHILD to terminate.
+ CHILD must be a child process that has not been reaped.
+ If STATUS is non-null, store the waitpid-style exit status into *STATUS
+ and tell wait_reading_process_output that it needs to look around.
+ If INTERRUPTIBLE, this function is interruptible by a signal. */
void
-wait_for_termination (pid_t pid)
+wait_for_termination (pid_t child, int *status, bool interruptible)
{
- wait_for_termination_1 (pid, 0);
+ get_child_status (child, status, 0, interruptible);
}
-/* Like the above, but allow keyboard interruption. */
-void
-interruptible_wait_for_termination (pid_t pid)
+/* Report whether the subprocess with process id CHILD has changed status.
+ Termination counts as a change of status.
+ CHILD must be a child process that has not been reaped.
+ If STATUS is non-null, store the waitpid-style exit status into *STATUS
+ and tell wait_reading_process_output that it needs to look around.
+ Use waitpid-style OPTIONS to check status, but do not wait.
+
+ Return CHILD if successful, 0 if no status is available because
+ the process's state has not changed. */
+pid_t
+child_status_changed (pid_t child, int *status, int options)
{
- wait_for_termination_1 (pid, 1);
+ return get_child_status (child, status, WNOHANG | options, 0);
}
/*
void
sys_suspend (void)
{
-#if defined (SIGTSTP) && !defined (MSDOS)
-
- {
- pid_t pgrp = getpgrp ();
- EMACS_KILLPG (pgrp, SIGTSTP);
- }
-
-#else /* No SIGTSTP */
+#ifndef DOS_NT
+ kill (0, SIGTSTP);
+#else
/* On a system where suspending is not implemented,
instead fork a subshell and let it talk directly to the terminal
while we wait. */
sys_subshell ();
-#endif /* no SIGTSTP */
+#endif
}
/* Fork a subshell. */
char oldwd[MAXPATHLEN+1]; /* Fixed length is safe on MSDOS. */
#endif
pid_t pid;
+ int status;
struct save_signal saved_handlers[5];
Lisp_Object dir;
unsigned char *volatile str_volatile = 0;
#ifdef DOS_NT
pid = 0;
save_signal_handlers (saved_handlers);
- synch_process_alive = 1;
#else
pid = vfork ();
if (pid == -1)
#ifdef DOS_NT /* MW, Aug 1993 */
getcwd (oldwd, sizeof oldwd);
if (sh == 0)
- sh = (char *) egetenv ("SUSPEND"); /* KFS, 1994-12-14 */
+ sh = egetenv ("SUSPEND"); /* KFS, 1994-12-14 */
#endif
if (sh == 0)
- sh = (char *) egetenv ("SHELL");
+ sh = egetenv ("SHELL");
if (sh == 0)
sh = "sh";
#endif
}
- close_process_descs (); /* Close Emacs's pipes/ptys */
-
#ifdef MSDOS /* Demacs 1.1.2 91/10/20 Manabu Higashida */
{
char *epwd = getenv ("PWD");
/* Do this now if we did not do it before. */
#ifndef MSDOS
save_signal_handlers (saved_handlers);
- synch_process_alive = 1;
#endif
#ifndef DOS_NT
- wait_for_termination (pid);
+ wait_for_termination (pid, &status, 0);
#endif
restore_signal_handlers (saved_handlers);
- synch_process_alive = 0;
}
static void
inherited_pgroup = getpid () == pgrp ? 0 : pgrp;
}
+/* Block and unblock SIGTTOU. */
+
+void
+block_tty_out_signal (void)
+{
+#ifdef SIGTTOU
+ sigset_t blocked;
+ sigemptyset (&blocked);
+ sigaddset (&blocked, SIGTTOU);
+ pthread_sigmask (SIG_BLOCK, &blocked, 0);
+#endif
+}
+
+void
+unblock_tty_out_signal (void)
+{
+#ifdef SIGTTOU
+ pthread_sigmask (SIG_SETMASK, &empty_mask, 0);
+#endif
+}
+
/* Safely set a controlling terminal FD's process group to PGID.
If we are not in the foreground already, POSIX requires tcsetpgrp
to deliver a SIGTTOU signal, which would stop us. This is an
tcsetpgrp_without_stopping (int fd, pid_t pgid)
{
#ifdef SIGTTOU
- signal_handler_t handler;
block_input ();
- handler = signal (SIGTTOU, SIG_IGN);
+ block_tty_out_signal ();
tcsetpgrp (fd, pgid);
- signal (SIGTTOU, handler);
+ unblock_tty_out_signal ();
unblock_input ();
#endif
}
if (tty_out->terminal->reset_terminal_modes_hook)
tty_out->terminal->reset_terminal_modes_hook (tty_out->terminal);
-#ifdef BSD_SYSTEM
/* Avoid possible loss of output when changing terminal modes. */
- fsync (fileno (tty_out->output));
-#endif
+ while (fdatasync (fileno (tty_out->output)) != 0 && errno == EINTR)
+ continue;
#ifndef DOS_NT
#ifdef F_SETOWN
/* When handling a signal, block nonfatal system signals that are caught
by Emacs. This makes race conditions less likely. */
sigaddset (&action->sa_mask, SIGALRM);
-#ifdef SIGCHLD
sigaddset (&action->sa_mask, SIGCHLD);
-#endif
#ifdef SIGDANGER
sigaddset (&action->sa_mask, SIGDANGER);
#endif
# undef sys_siglist
# ifdef _sys_siglist
# define sys_siglist _sys_siglist
+# elif HAVE_DECL___SYS_SIGLIST
+# define sys_siglist __sys_siglist
# else
# define sys_siglist my_sys_siglist
static char const *sys_siglist[NSIG];
deliver_thread_signal (sig, handle_arith_signal);
}
+#ifdef SIGDANGER
+
+/* Handler for SIGDANGER. */
+static void
+handle_danger_signal (int sig)
+{
+ malloc_warning ("Operating system warns that virtual memory is running low.\n");
+
+ /* It might be unsafe to call do_auto_save now. */
+ force_auto_save_soon ();
+}
+
+static void
+deliver_danger_signal (int sig)
+{
+ deliver_process_signal (sig, handle_danger_signal);
+}
+#endif
+
/* Treat SIG as a terminating signal, unless it is already ignored and
we are in --batch mode. Among other things, this makes nohup work. */
static void
# ifdef SIGAIO
sys_siglist[SIGAIO] = "LAN I/O interrupt";
# endif
-# ifdef SIGALRM
sys_siglist[SIGALRM] = "Alarm clock";
-# endif
# ifdef SIGBUS
sys_siglist[SIGBUS] = "Bus error";
# endif
-# ifdef SIGCLD
- sys_siglist[SIGCLD] = "Child status changed";
-# endif
-# ifdef SIGCHLD
sys_siglist[SIGCHLD] = "Child status changed";
-# endif
# ifdef SIGCONT
sys_siglist[SIGCONT] = "Continued";
# endif
# ifdef SIGGRANT
sys_siglist[SIGGRANT] = "Monitor mode granted";
# endif
-# ifdef SIGHUP
sys_siglist[SIGHUP] = "Hangup";
-# endif
sys_siglist[SIGILL] = "Illegal instruction";
sys_siglist[SIGINT] = "Interrupt";
# ifdef SIGIO
# ifdef SIGIOT
sys_siglist[SIGIOT] = "IOT trap";
# endif
-# ifdef SIGKILL
sys_siglist[SIGKILL] = "Killed";
-# endif
# ifdef SIGLOST
sys_siglist[SIGLOST] = "Resource lost";
# endif
# ifdef SIGPHONE
sys_siglist[SIGWIND] = "SIGPHONE";
# endif
-# ifdef SIGPIPE
sys_siglist[SIGPIPE] = "Broken pipe";
-# endif
# ifdef SIGPOLL
sys_siglist[SIGPOLL] = "Pollable event occurred";
# endif
# ifdef SIGPWR
sys_siglist[SIGPWR] = "Power-fail restart";
# endif
-# ifdef SIGQUIT
sys_siglist[SIGQUIT] = "Quit";
-# endif
# ifdef SIGRETRACT
sys_siglist[SIGRETRACT] = "Need to relinquish monitor mode";
# endif
void
emacs_abort (void)
{
- terminate_due_to_signal (SIGABRT, 10);
+ terminate_due_to_signal (SIGABRT, 40);
}
#endif
+/* Open FILE for Emacs use, using open flags OFLAG and mode MODE.
+ Arrange for subprograms to not inherit the file descriptor.
+ Prefer a method that is multithread-safe, if available.
+ Do not fail merely because the open was interrupted by a signal.
+ Allow the user to quit. */
+
int
-emacs_open (const char *path, int oflag, int mode)
+emacs_open (const char *file, int oflags, int mode)
{
- register int rtnval;
-
- while ((rtnval = open (path, oflag, mode)) == -1
- && (errno == EINTR))
+ int fd;
+ oflags |= O_CLOEXEC;
+ while ((fd = open (file, oflags, mode)) < 0 && errno == EINTR)
QUIT;
- return (rtnval);
+ if (! O_CLOEXEC && 0 <= fd)
+ fcntl (fd, F_SETFD, FD_CLOEXEC);
+ return fd;
+}
+
+/* Open FILE as a stream for Emacs use, with mode MODE.
+ Act like emacs_open with respect to threads, signals, and quits. */
+
+FILE *
+emacs_fopen (char const *file, char const *mode)
+{
+ int fd, omode, oflags;
+ int bflag = 0;
+ char const *m = mode;
+
+ switch (*m++)
+ {
+ case 'r': omode = O_RDONLY; oflags = 0; break;
+ case 'w': omode = O_WRONLY; oflags = O_CREAT | O_TRUNC; break;
+ case 'a': omode = O_WRONLY; oflags = O_CREAT | O_APPEND; break;
+ default: emacs_abort ();
+ }
+
+ while (*m)
+ switch (*m++)
+ {
+ case '+': omode = O_RDWR; break;
+ case 'b': bflag = O_BINARY; break;
+ case 't': bflag = O_TEXT; break;
+ default: /* Ignore. */ break;
+ }
+
+ fd = emacs_open (file, omode | oflags | bflag, 0666);
+ return fd < 0 ? 0 : fdopen (fd, mode);
}
int
return (bytes_written);
}
-
-static struct allocator const emacs_norealloc_allocator =
- { xmalloc, NULL, xfree, memory_full };
-
-/* Get the symbolic link value of FILENAME. Return a pointer to a
- NUL-terminated string. If readlink fails, return NULL and set
- errno. If the value fits in INITIAL_BUF, return INITIAL_BUF.
- Otherwise, allocate memory and return a pointer to that memory. If
- memory allocation fails, diagnose and fail without returning. If
- successful, store the length of the symbolic link into *LINKLEN. */
-char *
-emacs_readlink (char const *filename, char initial_buf[READLINK_BUFSIZE])
-{
- return careadlinkat (AT_FDCWD, filename, initial_buf, READLINK_BUFSIZE,
- &emacs_norealloc_allocator, careadlinkatcwd);
-}
\f
/* Return a struct timeval that is roughly equivalent to T.
Use the least timeval not less than T.
return proclist;
}
-#elif defined BSD_SYSTEM
+#elif defined DARWIN_OS || defined __FreeBSD__
Lisp_Object
list_system_processes (void)
{
-#if defined DARWIN_OS || defined __NetBSD__ || defined __OpenBSD__
+#ifdef DARWIN_OS
int mib[] = {CTL_KERN, KERN_PROC, KERN_PROC_ALL};
#else
int mib[] = {CTL_KERN, KERN_PROC, KERN_PROC_PROC};
len /= sizeof (struct kinfo_proc);
for (i = 0; i < len; i++)
{
-#if defined DARWIN_OS || defined __NetBSD__
+#ifdef DARWIN_OS
proclist = Fcons (make_fixnum_or_float (procs[i].kp_proc.p_pid), proclist);
-#elif defined __OpenBSD__
- proclist = Fcons (make_fixnum_or_float (procs[i].p_pid), proclist);
#else
proclist = Fcons (make_fixnum_or_float (procs[i].ki_pid), proclist);
#endif
EMACS_TIME up = make_emacs_time (0, 0);
block_input ();
- fup = fopen ("/proc/uptime", "r");
+ fup = emacs_fopen ("/proc/uptime", "r");
if (fup)
{
char name[PATH_MAX];
block_input ();
- fdev = fopen ("/proc/tty/drivers", "r");
+ fdev = emacs_fopen ("/proc/tty/drivers", "r");
if (fdev)
{
while (!feof (fdev) && !ferror (fdev))
{
- if (3 <= fscanf (fdev, "%*s %s %u %s %*s\n", name, &major, minor)
+ if (fscanf (fdev, "%*s %s %u %s %*s\n", name, &major, minor) >= 3
&& major == MAJOR (rdev))
{
minor_beg = strtoul (minor, &endp, 0);
unsigned long retval = 2 * 1024 * 1024; /* default: 2GB */
block_input ();
- fmem = fopen ("/proc/meminfo", "r");
+ fmem = emacs_fopen ("/proc/meminfo", "r");
if (fmem)
{
while (!feof (fmem) && !ferror (fmem))
{
- if (2 <= fscanf (fmem, "%s %lu kB\n", entry_name, &entry_value)
+ if (fscanf (fmem, "%s %lu kB\n", entry_name, &entry_value) >= 2
&& strcmp (entry_name, "MemTotal:") == 0)
{
retval = entry_value;
HCoop / bpt / emacs.git / blobdiff