Assume POSIX 1003.1-1988 or later for signal.h.

Exceptions: do not assume SIGCONT, SIGSTOP, SIGTSTP, SIGTTIN,
SIGTTOU, SIGUSR1, SIGUSR2, as Microsoft platforms lack these.
* admin/CPP-DEFINES (SIGALRM, SIGCHLD, SIGHUP, SIGKILL, SIGPIPE, SIGQUIT):
Remove.
(SIGTRAP): Remove this one too, as config.h no longer defines it.
* admin/merge-gnulib (GNULIB_MODULES): Add sig2str.
* configure.ac (PTY_OPEN, PTY_TTY_NAME_SPRINTF):
Use SIGCHLD rather than SIGCLD.
* lib/sig2str.c, lib/sig2str.h, m4/sig2str.m4: New files, from gnulib.
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* lib/makefile.w32-in (GNULIBOBJS): Add $(BUILD)/sig2str.$(O).
* src/process.c [subprocesses]: Include <c-ctype.h>, <sig2str.h>.
(deleted_pid_list, Fdelete_process, create_process)
(record_child_status_change, handle_child_signal, deliver_child_signal)
(init_process_emacs, syms_of_process):
Assume SIGCHLD is defined.
(parse_signal): Remove.  All uses removed.
(abbr_to_signal): New static function.
(Fsignal_process): Use it to convert signal names to ints.
* src/sysdep.c (sys_suspend) [!DOS_NT]: Use kill (0, ...) rather than
kill (getpgrp (), ...).
(emacs_sigaction_init): Assume SIGCHLD is defined.
(init_signals): Assume SIGALRM, SIGCHLD, SIGHUP, SIGKILL,
SIGPIPE, and SIGQUIT are defined.  Do not worry about SIGCLD any more.
* src/syssignal.h (EMACS_KILLPG): Remove.
All uses replaced by 'kill' with a negative pid.
(SIGCHLD): Remove definition, as we now assume SIGCHLD.
* src/w32proc.c (sys_kill): Support negative pids compatibly with POSIX.

Fixes: debbugs:13026

7 files changed, 70 insertions, 173 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index edd6924af50..2b283a609e3 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,26 @@
+2012-12-08  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Assume POSIX 1003.1-1988 or later for signal.h (Bug#13026).
+        Exceptions: do not assume SIGCONT, SIGSTOP, SIGTSTP, SIGTTIN,
+        SIGTTOU, SIGUSR1, SIGUSR2, as Microsoft platforms lack these.
+        * process.c [subprocesses]: Include <c-ctype.h>, <sig2str.h>.
+        (deleted_pid_list, Fdelete_process, create_process)
+        (record_child_status_change, handle_child_signal, deliver_child_signal)
+        (init_process_emacs, syms_of_process):
+        Assume SIGCHLD is defined.
+        (parse_signal): Remove.  All uses removed.
+        (abbr_to_signal): New static function.
+        (Fsignal_process): Use it to convert signal names to ints.
+        * sysdep.c (sys_suspend) [!DOS_NT]: Use kill (0, ...) rather than
+        kill (getpgrp (), ...).
+        (emacs_sigaction_init): Assume SIGCHLD is defined.
+        (init_signals): Assume SIGALRM, SIGCHLD, SIGHUP, SIGKILL,
+        SIGPIPE, and SIGQUIT are defined.  Do not worry about SIGCLD any more.
+        * syssignal.h (EMACS_KILLPG): Remove.
+        All uses replaced by 'kill' with a negative pid.
+        (SIGCHLD): Remove definition, as we now assume SIGCHLD.
+        * w32proc.c (sys_kill): Support negative pids compatibly with POSIX.
+
 2012-12-07  Paul Eggert  <eggert@cs.ucla.edu>
 
         * sysdep.c (get_child_status): Abort on internal error (Bug#13086).
diff --git a/src/callproc.c b/src/callproc.c
index e0528a791ea..70e349d0d3a 100644
--- a/src/callproc.c
+++ b/src/callproc.c
@@ -87,12 +87,10 @@ static int synch_process_fd;
 static void
 block_child_signal (void)
 {
-#ifdef SIGCHLD
   sigset_t blocked;
   sigemptyset (&blocked);
   sigaddset (&blocked, SIGCHLD);
   pthread_sigmask (SIG_BLOCK, &blocked, 0);
-#endif
 }
 
 /* Unblock SIGCHLD.  */
@@ -100,9 +98,7 @@ block_child_signal (void)
 static void
 unblock_child_signal (void)
 {
-#ifdef SIGCHLD
   pthread_sigmask (SIG_SETMASK, &empty_mask, 0);
-#endif
 }
 
 /* If P is reapable, record it as a deleted process and kill it.
@@ -118,7 +114,7 @@ record_kill_process (struct Lisp_Process *p)
     {
       p->alive = 0;
       record_deleted_pid (p->pid);
-      EMACS_KILLPG (p->pid, SIGKILL);
+      kill (- p->pid, SIGKILL);
     }
 
   unblock_child_signal ();
@@ -164,7 +160,7 @@ call_process_cleanup (Lisp_Object arg)
   if (synch_process_pid)
     {
       ptrdiff_t count = SPECPDL_INDEX ();
-      EMACS_KILLPG (synch_process_pid, SIGINT);
+      kill (-synch_process_pid, SIGINT);
       record_unwind_protect (call_process_kill, make_number (0));
       message1 ("Waiting for process to die...(type C-g again to kill it instantly)");
       immediate_quit = 1;
diff --git a/src/keyboard.c b/src/keyboard.c
index 1bb4c85dd7b..fc155c5a5f7 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -10688,7 +10688,7 @@ handle_interrupt (bool in_signal_handler)
       fflush (stdout);
       reset_all_sys_modes ();
 
-#ifdef SIGTSTP                  /* Support possible in later USG versions */
+#ifdef SIGTSTP
 /*
  * On systems which can suspend the current process and return to the original
  * shell, this command causes the user to end up back at the shell.
diff --git a/src/process.c b/src/process.c
index 007a07942e6..7b21d060cf8 100644
--- a/src/process.c
+++ b/src/process.c
@@ -91,6 +91,9 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <pty.h>
 #endif
 
+#include <c-ctype.h>
+#include <sig2str.h>
+
 #endif  /* subprocesses */
 
 #include "systime.h"
@@ -773,7 +776,6 @@ get_process (register Lisp_Object name)
 }
 
 
-#ifdef SIGCHLD
 /* Fdelete_process promises to immediately forget about the process, but in
    reality, Emacs needs to remember those processes until they have been
    treated by the SIGCHLD handler and waitpid has been invoked on them;
@@ -781,17 +783,14 @@ get_process (register Lisp_Object name)
 
    Some processes created by call-process are also put onto this list.  */
 static Lisp_Object deleted_pid_list;
-#endif
 
 void
 record_deleted_pid (pid_t pid)
 {
-#ifdef SIGCHLD
   deleted_pid_list = Fcons (make_fixnum_or_float (pid),
                             /* GC treated elements set to nil.  */
                             Fdelq (Qnil, deleted_pid_list));
 
-#endif
 }
 
 DEFUN ("delete-process", Fdelete_process, Sdelete_process, 1, 1, 0,
@@ -1581,9 +1580,7 @@ create_process (Lisp_Object process, char **new_argv, Lisp_Object current_dir)
 #ifndef WINDOWSNT
   int wait_child_setup[2];
 #endif
-#ifdef SIGCHLD
   sigset_t blocked;
-#endif
   /* Use volatile to protect variables from being clobbered by vfork.  */
   volatile int forkin, forkout;
   volatile int pty_flag = 0;
@@ -1680,13 +1677,11 @@ create_process (Lisp_Object process, char **new_argv, Lisp_Object current_dir)
 
   block_input ();
 
-#ifdef SIGCHLD
   /* Block SIGCHLD until we have a chance to store the new fork's
      pid in its process structure.  */
   sigemptyset (&blocked);
   sigaddset (&blocked, SIGCHLD);
   pthread_sigmask (SIG_BLOCK, &blocked, 0);
-#endif
 
 #ifndef WINDOWSNT
   pid = vfork ();
@@ -1794,10 +1789,8 @@ create_process (Lisp_Object process, char **new_argv, Lisp_Object current_dir)
       /* Emacs ignores SIGPIPE, but the child should not.  */
       signal (SIGPIPE, SIG_DFL);
 
-#ifdef SIGCHLD
         /* Stop blocking signals in the child.  */
       pthread_sigmask (SIG_SETMASK, &empty_mask, 0);
-#endif
 
       if (pty_flag)
         child_setup_tty (xforkout);
@@ -1818,9 +1811,7 @@ create_process (Lisp_Object process, char **new_argv, Lisp_Object current_dir)
     XPROCESS (process)->alive = 1;
 
   /* Stop blocking signals in the parent.  */
-#ifdef SIGCHLD
   pthread_sigmask (SIG_SETMASK, &empty_mask, 0);
-#endif
   unblock_input ();
 
   if (pid < 0)
@@ -4612,7 +4603,7 @@ wait_reading_process_output (intmax_t time_limit, int nsecs, int read_kbd,
                  yielding EBADF here or at select() call above.
                  So, SIGHUP is ignored (see def of PTY_TTY_NAME_SPRINTF
                  in m/ibmrt-aix.h), and here we just ignore the select error.
-                 Cleanup occurs c/o status_notify after SIGCLD. */
+                 Cleanup occurs c/o status_notify after SIGCHLD. */
               no_avail = 1; /* Cannot depend on values returned */
 #else
               emacs_abort ();
@@ -4810,10 +4801,8 @@ wait_reading_process_output (intmax_t time_limit, int nsecs, int read_kbd,
 #endif /* HAVE_PTYS */
               /* If we can detect process termination, don't consider the
                  process gone just because its pipe is closed.  */
-#ifdef SIGCHLD
               else if (nread == 0 && !NETCONN_P (proc) && !SERIALCONN_P (proc))
                 ;
-#endif
               else
                 {
                   /* Preserve status of processes already terminated.  */
@@ -5676,7 +5665,7 @@ return t unconditionally.  */)
 
    If we can, we try to signal PROCESS by sending control characters
    down the pty.  This allows us to signal inferiors who have changed
-   their uid, for which killpg would return an EPERM error.  */
+   their uid, for which kill would return an EPERM error.  */
 
 static void
 process_send_signal (Lisp_Object process, int signo, Lisp_Object current_group,
@@ -5814,7 +5803,7 @@ process_send_signal (Lisp_Object process, int signo, Lisp_Object current_group,
   if (!NILP (current_group))
     {
       if (ioctl (p->infd, TIOCSIGSEND, signo) == -1)
-        EMACS_KILLPG (gid, signo);
+        kill (-gid, signo);
     }
   else
     {
@@ -5822,7 +5811,7 @@ process_send_signal (Lisp_Object process, int signo, Lisp_Object current_group,
       kill (gid, signo);
     }
 #else /* ! defined (TIOCSIGSEND) */
-  EMACS_KILLPG (gid, signo);
+  kill (-gid, signo);
 #endif /* ! defined (TIOCSIGSEND) */
 }
 
@@ -5927,6 +5916,27 @@ traffic.  */)
   return process;
 }
 
+/* Return the integer value of the signal whose abbreviation is ABBR,
+   or a negative number if there is no such signal.  */
+static int
+abbr_to_signal (char const *name)
+{
+  int i, signo;
+  char sigbuf[20]; /* Large enough for all valid signal abbreviations.  */
+
+  if (!strncmp (name, "SIG", 3) || !strncmp (name, "sig", 3))
+    name += 3;
+
+  for (i = 0; i < sizeof sigbuf; i++)
+    {
+      sigbuf[i] = c_toupper (name[i]);
+      if (! sigbuf[i])
+        return str2sig (sigbuf, &signo) == 0 ? signo : -1;
+    }
+
+  return -1;
+}
+
 DEFUN ("signal-process", Fsignal_process, Ssignal_process,
        2, 2, "sProcess (name or number): \nnSignal code: ",
        doc: /* Send PROCESS the signal with code SIGCODE.
@@ -5937,6 +5947,7 @@ SIGCODE may be an integer, or a symbol whose name is a signal name.  */)
   (Lisp_Object process, Lisp_Object sigcode)
 {
   pid_t pid;
+  int signo;
 
   if (STRINGP (process))
     {
@@ -5966,12 +5977,11 @@ SIGCODE may be an integer, or a symbol whose name is a signal name.  */)
         error ("Cannot signal process %s", SDATA (XPROCESS (process)->name));
     }
 
-#define parse_signal(NAME, VALUE)               \
-  else if (!xstrcasecmp (name, NAME))           \
-    XSETINT (sigcode, VALUE)
-
   if (INTEGERP (sigcode))
-    CHECK_TYPE_RANGED_INTEGER (int, sigcode);
+    {
+      CHECK_TYPE_RANGED_INTEGER (int, sigcode);
+      signo = XINT (sigcode);
+    }
   else
     {
       char *name;
@@ -5979,96 +5989,12 @@ SIGCODE may be an integer, or a symbol whose name is a signal name.  */)
       CHECK_SYMBOL (sigcode);
       name = SSDATA (SYMBOL_NAME (sigcode));
 
-      if (!strncmp (name, "SIG", 3) || !strncmp (name, "sig", 3))
-        name += 3;
-
-      if (0)
-        ;
-#ifdef SIGUSR1
-      parse_signal ("usr1", SIGUSR1);
-#endif
-#ifdef SIGUSR2
-      parse_signal ("usr2", SIGUSR2);
-#endif
-      parse_signal ("term", SIGTERM);
-#ifdef SIGHUP
-      parse_signal ("hup", SIGHUP);
-#endif
-      parse_signal ("int", SIGINT);
-#ifdef SIGQUIT
-      parse_signal ("quit", SIGQUIT);
-#endif
-      parse_signal ("ill", SIGILL);
-      parse_signal ("abrt", SIGABRT);
-#ifdef SIGEMT
-      parse_signal ("emt", SIGEMT);
-#endif
-#ifdef SIGKILL
-      parse_signal ("kill", SIGKILL);
-#endif
-      parse_signal ("fpe", SIGFPE);
-#ifdef SIGBUS
-      parse_signal ("bus", SIGBUS);
-#endif
-      parse_signal ("segv", SIGSEGV);
-#ifdef SIGSYS
-      parse_signal ("sys", SIGSYS);
-#endif
-#ifdef SIGPIPE
-      parse_signal ("pipe", SIGPIPE);
-#endif
-#ifdef SIGALRM
-      parse_signal ("alrm", SIGALRM);
-#endif
-#ifdef SIGURG
-      parse_signal ("urg", SIGURG);
-#endif
-#ifdef SIGSTOP
-      parse_signal ("stop", SIGSTOP);
-#endif
-#ifdef SIGTSTP
-      parse_signal ("tstp", SIGTSTP);
-#endif
-#ifdef SIGCONT
-      parse_signal ("cont", SIGCONT);
-#endif
-#ifdef SIGCHLD
-      parse_signal ("chld", SIGCHLD);
-#endif
-#ifdef SIGTTIN
-      parse_signal ("ttin", SIGTTIN);
-#endif
-#ifdef SIGTTOU
-      parse_signal ("ttou", SIGTTOU);
-#endif
-#ifdef SIGIO
-      parse_signal ("io", SIGIO);
-#endif
-#ifdef SIGXCPU
-      parse_signal ("xcpu", SIGXCPU);
-#endif
-#ifdef SIGXFSZ
-      parse_signal ("xfsz", SIGXFSZ);
-#endif
-#ifdef SIGVTALRM
-      parse_signal ("vtalrm", SIGVTALRM);
-#endif
-#ifdef SIGPROF
-      parse_signal ("prof", SIGPROF);
-#endif
-#ifdef SIGWINCH
-      parse_signal ("winch", SIGWINCH);
-#endif
-#ifdef SIGINFO
-      parse_signal ("info", SIGINFO);
-#endif
-      else
+      signo = abbr_to_signal (name);
+      if (signo < 0)
         error ("Undefined signal name %s", name);
     }
 
-#undef parse_signal
-
-  return make_number (kill (pid, XINT (sigcode)));
+  return make_number (kill (pid, signo));
 }
 
 DEFUN ("process-send-eof", Fprocess_send_eof, Sprocess_send_eof, 0, 1, 0,
@@ -6150,8 +6076,6 @@ process has been transmitted to the serial port.  */)
   return process;
 }
 
-#ifdef SIGCHLD
-
 /* The main Emacs thread records child processes in three places:
 
    - Vprocess_alist, for asynchronous subprocesses, which are child
@@ -6268,8 +6192,6 @@ deliver_child_signal (int sig)
 {
   deliver_process_signal (sig, handle_child_signal);
 }
-
-#endif /* SIGCHLD */
 
 
 static Lisp_Object
@@ -7118,7 +7040,6 @@ init_process_emacs (void)
 
   inhibit_sentinels = 0;
 
-#ifdef SIGCHLD
 #ifndef CANNOT_DUMP
   if (! noninteractive || initialized)
 #endif
@@ -7127,7 +7048,6 @@ init_process_emacs (void)
       emacs_sigaction_init (&action, deliver_child_signal);
       sigaction (SIGCHLD, &action, 0);
     }
-#endif
 
   FD_ZERO (&input_wait_mask);
   FD_ZERO (&non_keyboard_wait_mask);
@@ -7154,9 +7074,7 @@ init_process_emacs (void)
 #endif
 
   Vprocess_alist = Qnil;
-#ifdef SIGCHLD
   deleted_pid_list = Qnil;
-#endif
   for (i = 0; i < MAXDESC; i++)
     {
       chan_process[i] = Qnil;
@@ -7283,9 +7201,7 @@ syms_of_process (void)
   DEFSYM (Qlast_nonmenu_event, "last-nonmenu-event");
 
   staticpro (&Vprocess_alist);
-#ifdef SIGCHLD
   staticpro (&deleted_pid_list);
-#endif
 
 #endif  /* subprocesses */
 
diff --git a/src/sysdep.c b/src/sysdep.c
index 9c904850401..5291c5d59aa 100644
--- a/src/sysdep.c
+++ b/src/sysdep.c
@@ -457,20 +457,15 @@ static void restore_signal_handlers (struct save_signal *);
 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.  */
@@ -1518,9 +1513,7 @@ emacs_sigaction_init (struct sigaction *action, signal_handler_t handler)
   /* 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
@@ -1700,18 +1693,11 @@ init_signals (bool dumping)
 # 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
@@ -1731,9 +1717,7 @@ init_signals (bool dumping)
 # 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
@@ -1745,9 +1729,7 @@ init_signals (bool dumping)
 # ifdef SIGIOT
       sys_siglist[SIGIOT] = "IOT trap";
 # endif
-# ifdef SIGKILL
       sys_siglist[SIGKILL] = "Killed";
-# endif
 # ifdef SIGLOST
       sys_siglist[SIGLOST] = "Resource lost";
 # endif
@@ -1760,9 +1742,7 @@ init_signals (bool dumping)
 # ifdef SIGPHONE
       sys_siglist[SIGWIND] = "SIGPHONE";
 # endif
-# ifdef SIGPIPE
       sys_siglist[SIGPIPE] = "Broken pipe";
-# endif
 # ifdef SIGPOLL
       sys_siglist[SIGPOLL] = "Pollable event occurred";
 # endif
@@ -1775,9 +1755,7 @@ init_signals (bool dumping)
 # 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
diff --git a/src/syssignal.h b/src/syssignal.h
index 2bf2f046aa5..8f9b5f0546a 100644
--- a/src/syssignal.h
+++ b/src/syssignal.h
@@ -54,26 +54,6 @@ char const *safe_strsignal (int) ATTRIBUTE_CONST;
 # define emacs_raise(sig) raise (sig)
 #endif
 
-/* On bsd, [man says] kill does not accept a negative number to kill a pgrp.
-   Must do that using the killpg call.  */
-#ifdef BSD_SYSTEM
-#define EMACS_KILLPG(gid, signo) (killpg ( (gid), (signo)))
-#else
-#ifdef WINDOWSNT
-#define EMACS_KILLPG(gid, signo) (kill (gid, signo))
-#else
-#define EMACS_KILLPG(gid, signo) (kill   (-(gid), (signo)))
-#endif
-#endif
-
-/* Define SIGCHLD as an alias for SIGCLD.  There are many conditionals
-   testing SIGCHLD.  */
-#ifdef SIGCLD
-#ifndef SIGCHLD
-#define SIGCHLD SIGCLD
-#endif /* SIGCHLD */
-#endif /* ! defined (SIGCLD) */
-
 #ifndef HAVE_STRSIGNAL
 # define strsignal(sig) safe_strsignal (sig)
 #endif
diff --git a/src/w32proc.c b/src/w32proc.c
index 0b36804b0e8..d888200c556 100644
--- a/src/w32proc.c
+++ b/src/w32proc.c
@@ -2122,6 +2122,10 @@ sys_kill (int pid, int sig)
   int need_to_free = 0;
   int rc = 0;
 
+  /* Each process is in its own process group.  */
+  if (pid < 0)
+    pid = -pid;
+
   /* Only handle signals that will result in the process dying */
   if (sig != SIGINT && sig != SIGKILL && sig != SIGQUIT && sig != SIGHUP)
     {