Subject: Re: bug#13026: Assume POSIX 1003.1-1988 or later for signal.h.

From: Paul Eggert <[email-masked]>
Date: Sun, 02 Dec 2012 17:31:48 -0800

On 11/30/2012 12:54 AM, Eli Zaretskii wrote:
> Maybe a better fix there would be to
> have an array of data (name and value of each signal), and loop
> through it, instead of using if-elseif.

Sure, that's easy enough.  Gnulib already has a module to do that.
Revised patch attached (most of the new stuff is just code
copied from Gnulib).  As a bonus, this fixes signal-process to
handle several signal names that it currently doesn't support,
such as those of the real-time signals.

> By the way, an alternative way of dealing with the lack of Posix
> signals on Windows is to condition the related fragments on WINDOWSNT,
> and remove the "#ifdef SIGFOO" conditions for Posix signals.

I'd rather use the Autoconf style, which is to test for individual
features rather than test for operating systems, as that tends to
make maintenance easier when operating systems or the emulations
mutate.

=== modified file 'ChangeLog'
--- ChangeLog	2012-11-30 18:25:59 +0000
+++ ChangeLog	2012-12-03 01:24:25 +0000
@@ -1,3 +1,11 @@
+2012-12-03  Paul Eggert  <[email-masked]>
+
+	Assume POSIX 1003.1-1988 or later for signal.h (Bug#13026).
+	* 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.
+
 2012-11-30  Paul Eggert  <[email-masked]>
 
 	Merge from gnulib for 'inline' (Bug#13040), incorporating:

=== modified file 'admin/CPP-DEFINES'
--- admin/CPP-DEFINES	2012-11-24 17:20:49 +0000
+++ admin/CPP-DEFINES	2012-11-29 06:46:35 +0000
@@ -419,14 +419,7 @@
 PURESIZE
 RUN_TIME_REMAP
 SETUP_SLAVE_PTY
-SIGALRM
-SIGCHLD
-SIGHUP
-SIGKILL
 SIGNALS_VIA_CHARACTERS
-SIGPIPE
-SIGQUIT
-SIGTRAP
 STDC_HEADERS
 SYSTEM_PURESIZE_EXTRA
 SYSTEM_MALLOC

=== modified file 'admin/ChangeLog'
--- admin/ChangeLog	2012-11-24 17:20:49 +0000
+++ admin/ChangeLog	2012-12-03 01:24:25 +0000
@@ -1,3 +1,11 @@
+2012-12-03  Paul Eggert  <[email-masked]>
+
+	Assume POSIX 1003.1-1988 or later for signal.h (Bug#13026).
+	* CPP-DEFINES (SIGALRM, SIGCHLD, SIGHUP, SIGKILL, SIGPIPE, SIGQUIT):
+	Remove.
+	(SIGTRAP): Remove this one too, as config.h no longer defines it.
+	* merge-gnulib (GNULIB_MODULES): Add sig2str.
+
 2012-11-24  Ken Brown  <[email-masked]>
 
 	* CPP-DEFINES (HAVE_MOUSE): Remove.

=== modified file 'admin/merge-gnulib'
--- admin/merge-gnulib	2012-11-17 22:12:47 +0000
+++ admin/merge-gnulib	2012-12-03 01:24:25 +0000
@@ -32,7 +32,7 @@
   fcntl-h filemode getloadavg getopt-gnu gettime gettimeofday
   ignore-value intprops largefile lstat
   manywarnings mktime pselect pthread_sigmask readlink
-  socklen stat-time stdalign stdarg stdbool stdio
+  sig2str socklen stat-time stdalign stdarg stdbool stdio
   strftime strtoimax strtoumax symlink sys_stat
   sys_time time timer-time timespec-add timespec-sub utimens
   warnings

=== modified file 'configure.ac'
--- configure.ac	2012-11-27 03:10:32 +0000
+++ configure.ac	2012-11-29 06:46:35 +0000
@@ -3600,7 +3600,7 @@
     AC_DEFINE(PTY_ITERATION, [])
     dnl Not used, because PTY_ITERATION is defined.
     AC_DEFINE(FIRST_PTY_LETTER, ['q'])
-    AC_DEFINE(PTY_OPEN, [ { struct sigaction ocstat, cstat; struct stat stb; char * name; sigemptyset(&cstat.sa_mask); cstat.sa_handler = SIG_DFL; cstat.sa_flags = 0; sigaction(SIGCLD, &cstat, &ocstat); name = _getpty (&fd, O_RDWR | O_NDELAY, 0600, 0); sigaction(SIGCLD, &ocstat, (struct sigaction *)0); if (name == 0) return -1; if (fd < 0) return -1; if (fstat (fd, &stb) < 0) return -1; strcpy (pty_name, name); }])
+    AC_DEFINE(PTY_OPEN, [ { struct sigaction ocstat, cstat; struct stat stb; char * name; sigemptyset(&cstat.sa_mask); cstat.sa_handler = SIG_DFL; cstat.sa_flags = 0; sigaction(SIGCHLD, &cstat, &ocstat); name = _getpty (&fd, O_RDWR | O_NDELAY, 0600, 0); sigaction(SIGCHLD, &ocstat, (struct sigaction *)0); if (name == 0) return -1; if (fd < 0) return -1; if (fstat (fd, &stb) < 0) return -1; strcpy (pty_name, name); }])
     dnl No need to get the pty name at all.
     AC_DEFINE(PTY_NAME_SPRINTF, [])
     dnl No need to use sprintf to get the tty name--we get that from _getpty.
@@ -3611,12 +3611,12 @@
     dnl On SysVr4, grantpt(3) forks a subprocess, so keep sigchld_handler()
     dnl from intercepting that death.  If any child but grantpt's should die
     dnl within, it should be caught after sigrelse(2).
-    AC_DEFINE(PTY_TTY_NAME_SPRINTF, [{ char *ptsname (int), *ptyname; int grantpt_result; sigset_t blocked; sigemptyset (&blocked); sigaddset (&blocked, SIGCLD); pthread_sigmask (SIG_BLOCK, &blocked, 0); grantpt_result = grantpt (fd); pthread_sigmask (SIG_UNBLOCK, &blocked, 0); if (grantpt_result == -1 || unlockpt (fd) == -1 || !(ptyname = ptsname (fd))) { emacs_close (fd); return -1; } snprintf (pty_name, sizeof pty_name, "%s", ptyname); }])
+    AC_DEFINE(PTY_TTY_NAME_SPRINTF, [{ char *ptsname (int), *ptyname; int grantpt_result; sigset_t blocked; sigemptyset (&blocked); sigaddset (&blocked, SIGCHLD); pthread_sigmask (SIG_BLOCK, &blocked, 0); grantpt_result = grantpt (fd); pthread_sigmask (SIG_UNBLOCK, &blocked, 0); if (grantpt_result == -1 || unlockpt (fd) == -1 || !(ptyname = ptsname (fd))) { emacs_close (fd); return -1; } snprintf (pty_name, sizeof pty_name, "%s", ptyname); }])
     ;;
 
   unixware )
     dnl Comments are as per sol2*.
-    AC_DEFINE(PTY_TTY_NAME_SPRINTF, [{ char *ptsname (int), *ptyname; int grantpt_result; sigset_t blocked; sigemptyset (&blocked); sigaddset (&blocked, SIGCLD); pthread_sigmask (SIG_BLOCK, &blocked, 0); grantpt_result = grantpt (fd); pthread_sigmask (SIG_UNBLOCK, &blocked, 0); if (grantpt_result == -1) fatal("could not grant slave pty"); if (unlockpt(fd) == -1) fatal("could not unlock slave pty"); if (!(ptyname = ptsname(fd))) fatal ("could not enable slave pty"); snprintf (pty_name, sizeof pty_name, "%s", ptyname); }])
+    AC_DEFINE(PTY_TTY_NAME_SPRINTF, [{ char *ptsname (int), *ptyname; int grantpt_result; sigset_t blocked; sigemptyset (&blocked); sigaddset (&blocked, SIGCHLD); pthread_sigmask (SIG_BLOCK, &blocked, 0); grantpt_result = grantpt (fd); pthread_sigmask (SIG_UNBLOCK, &blocked, 0); if (grantpt_result == -1) fatal("could not grant slave pty"); if (unlockpt(fd) == -1) fatal("could not unlock slave pty"); if (!(ptyname = ptsname(fd))) fatal ("could not enable slave pty"); snprintf (pty_name, sizeof pty_name, "%s", ptyname); }])
     ;;
 esac

=== modified file 'lib/gnulib.mk'
--- lib/gnulib.mk	2012-11-30 18:25:59 +0000
+++ lib/gnulib.mk	2012-12-03 01:24:25 +0000
@@ -21,7 +21,7 @@
 # the same distribution terms as the rest of that program.
 #
 # Generated by gnulib-tool.
-# Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --avoid=at-internal --avoid=errno --avoid=fchdir --avoid=fcntl --avoid=fstat --avoid=malloc-posix --avoid=msvc-inval --avoid=msvc-nothrow --avoid=openat-die --avoid=openat-h --avoid=raise --avoid=save-cwd --avoid=select --avoid=sigprocmask --avoid=sys_types --avoid=threadlib --makefile-name=gnulib.mk --conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files alloca-opt c-ctype c-strcase careadlinkat close-stream crypto/md5 crypto/sha1 crypto/sha256 crypto/sha512 dtoastr dtotimespec dup2 environ execinfo faccessat fcntl-h filemode getloadavg getopt-gnu gettime gettimeofday ignore-value intprops largefile lstat manywarnings mktime pselect pthread_sigmask readlink socklen stat-time stdalign stdarg stdbool stdio strftime strtoimax strtoumax symlink sys_stat sys_time time timer-time timespec-add timespec-sub utimens warnings
+# Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --avoid=at-internal --avoid=errno --avoid=fchdir --avoid=fcntl --avoid=fstat --avoid=malloc-posix --avoid=msvc-inval --avoid=msvc-nothrow --avoid=openat-die --avoid=openat-h --avoid=raise --avoid=save-cwd --avoid=select --avoid=sigprocmask --avoid=sys_types --avoid=threadlib --makefile-name=gnulib.mk --conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files alloca-opt c-ctype c-strcase careadlinkat close-stream crypto/md5 crypto/sha1 crypto/sha256 crypto/sha512 dtoastr dtotimespec dup2 environ execinfo faccessat fcntl-h filemode getloadavg getopt-gnu gettime gettimeofday ignore-value intprops largefile lstat manywarnings mktime pselect pthread_sigmask readlink sig2str socklen stat-time stdalign stdarg stdbool stdio strftime strtoimax strtoumax symlink sys_stat sys_time time timer-time timespec-add timespec-sub utimens warnings

 MOSTLYCLEANFILES += core *.stackdump
@@ -457,6 +457,15 @@
 
 ## end   gnulib module root-uid
 
+## begin gnulib module sig2str
+
+
+EXTRA_DIST += sig2str.c sig2str.h
+
+EXTRA_libgnu_a_SOURCES += sig2str.c
+
+## end   gnulib module sig2str
+
 ## begin gnulib module signal-h
 
 BUILT_SOURCES += signal.h

=== added file 'lib/sig2str.c'
--- lib/sig2str.c	1970-01-01 00:00:00 +0000
+++ lib/sig2str.c	2012-12-03 01:24:25 +0000
@@ -0,0 +1,345 @@
+/* sig2str.c -- convert between signal names and numbers
+
+   Copyright (C) 2002, 2004, 2006, 2009-2012 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by Paul Eggert.  */
+
+#include <config.h>
+
+#include <limits.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "sig2str.h"
+
+#ifndef SIGRTMIN
+# define SIGRTMIN 0
+# undef SIGRTMAX
+#endif
+#ifndef SIGRTMAX
+# define SIGRTMAX (SIGRTMIN - 1)
+#endif
+
+#define NUMNAME(name) { SIG##name, #name }
+
+/* Signal names and numbers.  Put the preferred name first.  */
+static struct numname { int num; char const name[8]; } numname_table[] =
+  {
+    /* Signals required by POSIX 1003.1-2001 base, listed in
+       traditional numeric order where possible.  */
+#ifdef SIGHUP
+    NUMNAME (HUP),
+#endif
+#ifdef SIGINT
+    NUMNAME (INT),
+#endif
+#ifdef SIGQUIT
+    NUMNAME (QUIT),
+#endif
+#ifdef SIGILL
+    NUMNAME (ILL),
+#endif
+#ifdef SIGTRAP
+    NUMNAME (TRAP),
+#endif
+#ifdef SIGABRT
+    NUMNAME (ABRT),
+#endif
+#ifdef SIGFPE
+    NUMNAME (FPE),
+#endif
+#ifdef SIGKILL
+    NUMNAME (KILL),
+#endif
+#ifdef SIGSEGV
+    NUMNAME (SEGV),
+#endif
+    /* On Haiku, SIGSEGV == SIGBUS, but we prefer SIGSEGV to match
+       strsignal.c output, so SIGBUS must be listed second.  */
+#ifdef SIGBUS
+    NUMNAME (BUS),
+#endif
+#ifdef SIGPIPE
+    NUMNAME (PIPE),
+#endif
+#ifdef SIGALRM
+    NUMNAME (ALRM),
+#endif
+#ifdef SIGTERM
+    NUMNAME (TERM),
+#endif
+#ifdef SIGUSR1
+    NUMNAME (USR1),
+#endif
+#ifdef SIGUSR2
+    NUMNAME (USR2),
+#endif
+#ifdef SIGCHLD
+    NUMNAME (CHLD),
+#endif
+#ifdef SIGURG
+    NUMNAME (URG),
+#endif
+#ifdef SIGSTOP
+    NUMNAME (STOP),
+#endif
+#ifdef SIGTSTP
+    NUMNAME (TSTP),
+#endif
+#ifdef SIGCONT
+    NUMNAME (CONT),
+#endif
+#ifdef SIGTTIN
+    NUMNAME (TTIN),
+#endif
+#ifdef SIGTTOU
+    NUMNAME (TTOU),
+#endif
+
+    /* Signals required by POSIX 1003.1-2001 with the XSI extension.  */
+#ifdef SIGSYS
+    NUMNAME (SYS),
+#endif
+#ifdef SIGPOLL
+    NUMNAME (POLL),
+#endif
+#ifdef SIGVTALRM
+    NUMNAME (VTALRM),
+#endif
+#ifdef SIGPROF
+    NUMNAME (PROF),
+#endif
+#ifdef SIGXCPU
+    NUMNAME (XCPU),
+#endif
+#ifdef SIGXFSZ
+    NUMNAME (XFSZ),
+#endif
+
+    /* Unix Version 7.  */
+#ifdef SIGIOT
+    NUMNAME (IOT),      /* Older name for ABRT.  */
+#endif
+#ifdef SIGEMT
+    NUMNAME (EMT),
+#endif
+
+    /* USG Unix.  */
+#ifdef SIGPHONE
+    NUMNAME (PHONE),
+#endif
+#ifdef SIGWIND
+    NUMNAME (WIND),
+#endif
+
+    /* Unix System V.  */
+#ifdef SIGCLD
+    NUMNAME (CLD),
+#endif
+#ifdef SIGPWR
+    NUMNAME (PWR),
+#endif
+
+    /* GNU/Linux 2.2 and Solaris 8.  */
+#ifdef SIGCANCEL
+    NUMNAME (CANCEL),
+#endif
+#ifdef SIGLWP
+    NUMNAME (LWP),
+#endif
+#ifdef SIGWAITING
+    NUMNAME (WAITING),
+#endif
+#ifdef SIGFREEZE
+    NUMNAME (FREEZE),
+#endif
+#ifdef SIGTHAW
+    NUMNAME (THAW),
+#endif
+#ifdef SIGLOST
+    NUMNAME (LOST),
+#endif
+#ifdef SIGWINCH
+    NUMNAME (WINCH),
+#endif
+
+    /* GNU/Linux 2.2.  */
+#ifdef SIGINFO
+    NUMNAME (INFO),
+#endif
+#ifdef SIGIO
+    NUMNAME (IO),
+#endif
+#ifdef SIGSTKFLT
+    NUMNAME (STKFLT),
+#endif
+
+    /* AIX 5L.  */
+#ifdef SIGDANGER
+    NUMNAME (DANGER),
+#endif
+#ifdef SIGGRANT
+    NUMNAME (GRANT),
+#endif
+#ifdef SIGMIGRATE
+    NUMNAME (MIGRATE),
+#endif
+#ifdef SIGMSG
+    NUMNAME (MSG),
+#endif
+#ifdef SIGPRE
+    NUMNAME (PRE),
+#endif
+#ifdef SIGRETRACT
+    NUMNAME (RETRACT),
+#endif
+#ifdef SIGSAK
+    NUMNAME (SAK),
+#endif
+#ifdef SIGSOUND
+    NUMNAME (SOUND),
+#endif
+
+    /* Older AIX versions.  */
+#ifdef SIGALRM1
+    NUMNAME (ALRM1),    /* unknown; taken from Bash 2.05 */
+#endif
+#ifdef SIGKAP
+    NUMNAME (KAP),      /* Older name for SIGGRANT.  */
+#endif
+#ifdef SIGVIRT
+    NUMNAME (VIRT),     /* unknown; taken from Bash 2.05 */
+#endif
+#ifdef SIGWINDOW
+    NUMNAME (WINDOW),   /* Older name for SIGWINCH.  */
+#endif
+
+    /* BeOS */
+#ifdef SIGKILLTHR
+    NUMNAME (KILLTHR),
+#endif
+
+    /* Older HP-UX versions.  */
+#ifdef SIGDIL
+    NUMNAME (DIL),
+#endif
+
+    /* Korn shell and Bash, of uncertain vintage.  */
+    { 0, "EXIT" }
+  };
+
+#define NUMNAME_ENTRIES (sizeof numname_table / sizeof numname_table[0])
+
+/* ISDIGIT differs from isdigit, as follows:
+   - Its arg may be any int or unsigned int; it need not be an unsigned char
+     or EOF.
+   - It's typically faster.
+   POSIX says that only '0' through '9' are digits.  Prefer ISDIGIT to
+   isdigit unless it's important to use the locale's definition
+   of "digit" even when the host does not conform to POSIX.  */
+#define ISDIGIT(c) ((unsigned int) (c) - '0' <= 9)
+
+/* Convert the signal name SIGNAME to a signal number.  Return the
+   signal number if successful, -1 otherwise.  */
+
+static int
+str2signum (char const *signame)
+{
+  if (ISDIGIT (*signame))
+    {
+      char *endp;
+      long int n = strtol (signame, &endp, 10);
+      if (! *endp && n <= SIGNUM_BOUND)
+        return n;
+    }
+  else
+    {
+      unsigned int i;
+      for (i = 0; i < NUMNAME_ENTRIES; i++)
+        if (strcmp (numname_table[i].name, signame) == 0)
+          return numname_table[i].num;
+
+      {
+        char *endp;
+        int rtmin = SIGRTMIN;
+        int rtmax = SIGRTMAX;
+
+        if (0 < rtmin && strncmp (signame, "RTMIN", 5) == 0)
+          {
+            long int n = strtol (signame + 5, &endp, 10);
+            if (! *endp && 0 <= n && n <= rtmax - rtmin)
+              return rtmin + n;
+          }
+        else if (0 < rtmax && strncmp (signame, "RTMAX", 5) == 0)
+          {
+            long int n = strtol (signame + 5, &endp, 10);
+            if (! *endp && rtmin - rtmax <= n && n <= 0)
+              return rtmax + n;
+          }
+      }
+    }
+
+  return -1;
+}
+
+/* Convert the signal name SIGNAME to the signal number *SIGNUM.
+   Return 0 if successful, -1 otherwise.  */
+
+int
+str2sig (char const *signame, int *signum)
+{
+  *signum = str2signum (signame);
+  return *signum < 0 ? -1 : 0;
+}
+
+/* Convert SIGNUM to a signal name in SIGNAME.  SIGNAME must point to
+   a buffer of at least SIG2STR_MAX bytes.  Return 0 if successful, -1
+   otherwise.  */
+
+int
+sig2str (int signum, char *signame)
+{
+  unsigned int i;
+  for (i = 0; i < NUMNAME_ENTRIES; i++)
+    if (numname_table[i].num == signum)
+      {
+        strcpy (signame, numname_table[i].name);
+        return 0;
+      }
+
+  {
+    int rtmin = SIGRTMIN;
+    int rtmax = SIGRTMAX;
+
+    if (! (rtmin <= signum && signum <= rtmax))
+      return -1;
+
+    if (signum <= rtmin + (rtmax - rtmin) / 2)
+      {
+        int delta = signum - rtmin;
+        sprintf (signame, delta ? "RTMIN+%d" : "RTMIN", delta);
+      }
+    else
+      {
+        int delta = rtmax - signum;
+        sprintf (signame, delta ? "RTMAX-%d" : "RTMAX", delta);
+      }
+
+    return 0;
+  }
+}

=== added file 'lib/sig2str.h'
--- lib/sig2str.h	1970-01-01 00:00:00 +0000
+++ lib/sig2str.h	2012-12-03 01:24:25 +0000
@@ -0,0 +1,43 @@
+/* sig2str.h -- convert between signal names and numbers
+
+   Copyright (C) 2002, 2005, 2009-2012 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by Paul Eggert.  */
+
+#include <signal.h>
+
+/* Don't override system declarations of SIG2STR_MAX, sig2str, str2sig.  */
+#ifndef SIG2STR_MAX
+
+# include "intprops.h"
+
+/* Size of a buffer needed to hold a signal name like "HUP".  */
+# define SIG2STR_MAX (sizeof "SIGRTMAX" + INT_STRLEN_BOUND (int) - 1)
+
+int sig2str (int, char *);
+int str2sig (char const *, int *);
+
+#endif
+
+/* An upper bound on signal numbers allowed by the system.  */
+
+#if defined _sys_nsig
+# define SIGNUM_BOUND (_sys_nsig - 1)
+#elif defined NSIG
+# define SIGNUM_BOUND (NSIG - 1)
+#else
+# define SIGNUM_BOUND 64
+#endif

=== modified file 'm4/gnulib-comp.m4'
--- m4/gnulib-comp.m4	2012-11-30 18:25:59 +0000
+++ m4/gnulib-comp.m4	2012-12-03 01:24:25 +0000
@@ -87,6 +87,7 @@
   # Code from module pthread_sigmask:
   # Code from module readlink:
   # Code from module root-uid:
+  # Code from module sig2str:
   # Code from module signal-h:
   # Code from module snippet/_Noreturn:
   # Code from module snippet/arg-nonnull:
@@ -245,6 +246,11 @@
     gl_PREREQ_READLINK
   fi
   gl_UNISTD_MODULE_INDICATOR([readlink])
+  gl_FUNC_SIG2STR
+  if test $ac_cv_func_sig2str = no; then
+    AC_LIBOBJ([sig2str])
+    gl_PREREQ_SIG2STR
+  fi
   gl_SIGNAL_H
   gl_TYPE_SOCKLEN_T
   gt_TYPE_SSIZE_T
@@ -681,6 +687,8 @@
   lib/sha256.h
   lib/sha512.c
   lib/sha512.h
+  lib/sig2str.c
+  lib/sig2str.h
   lib/signal.in.h
   lib/stat-time.c
   lib/stat-time.h
@@ -760,6 +768,7 @@
   m4/sha1.m4
   m4/sha256.m4
   m4/sha512.m4
+  m4/sig2str.m4
   m4/signal_h.m4
   m4/socklen.m4
   m4/ssize_t.m4

=== added file 'm4/sig2str.m4'
--- m4/sig2str.m4	1970-01-01 00:00:00 +0000
+++ m4/sig2str.m4	2012-12-03 01:24:25 +0000
@@ -0,0 +1,15 @@
+# serial 7
+dnl Copyright (C) 2002, 2005-2006, 2009-2012 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_FUNC_SIG2STR],
+[
+  AC_CHECK_FUNCS([sig2str])
+])
+
+# Prerequisites of lib/sig2str.c.
+AC_DEFUN([gl_PREREQ_SIG2STR], [
+  :
+])

=== modified file 'src/ChangeLog'
--- src/ChangeLog	2012-12-03 01:08:31 +0000
+++ src/ChangeLog	2012-12-03 01:24:25 +0000
@@ -1,3 +1,26 @@
+2012-12-03  Paul Eggert  <[email-masked]>
+
+	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 (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.
+	(Fsignal_process): Use abbr_to_signal to convert signal names to ints.
+	* sysdep.c: Include <sig2str.h>.
+	(sys_suspend) [!DOS_NT]: Use kill (0, ...) rather than
+	kill (getpgrp (), ...).
+	(emacs_sigaction_init): Assume SIGCHLD is defined.
+	(abbr_to_signal): New function.
+	(init_signals): Assume SIGALRM, SIGCHLD, SIGHUP, SIGKILL,
+	SIGPIPE, and SIGQUIT are defined.  Do not worry about SIGCLD any more.
+	* syssignal.h (abbr_to_signal): New decl.
+	(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.
+
 2012-12-03  Chong Yidong  <[email-masked]>
 
 	* fileio.c (Vauto_save_list_file_name): Doc fix.

=== modified file 'src/callproc.c'
--- src/callproc.c	2012-12-02 19:16:45 +0000
+++ src/callproc.c	2012-12-03 01:17:59 +0000
@@ -97,7 +97,7 @@
   CONS_TO_INTEGER (Fcar (fdpid), int, fd);
   CONS_TO_INTEGER (Fcdr (fdpid), pid_t, pid);
   emacs_close (fd);
-  EMACS_KILLPG (pid, SIGKILL);
+  kill (-pid, SIGKILL);
   synch_process_alive = 0;
   return Qnil;
 }
@@ -134,7 +134,7 @@
       return Qnil;
     }
 
-  if (EMACS_KILLPG (pid, SIGINT) == 0)
+  if (kill (-pid, SIGINT) == 0)
     {
       ptrdiff_t count = SPECPDL_INDEX ();
       record_unwind_protect (call_process_kill, fdpid);

=== modified file 'src/keyboard.c'
--- src/keyboard.c	2012-11-27 05:17:07 +0000
+++ src/keyboard.c	2012-11-29 21:33:52 +0000
@@ -10689,7 +10689,7 @@
       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.

=== modified file 'src/process.c'
--- src/process.c	2012-12-02 19:16:45 +0000
+++ src/process.c	2012-12-03 01:24:25 +0000
@@ -773,13 +773,11 @@
 }

-#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;
    otherwise they might fill up the kernel's process table.  */
 static Lisp_Object deleted_pid_list;
-#endif
 
 DEFUN ("delete-process", Fdelete_process, Sdelete_process, 1, 1, 0,
        doc: /* Delete PROCESS: kill it and forget about it immediately.
@@ -802,7 +800,6 @@
     }
   else if (p->infd >= 0)
     {
-#ifdef SIGCHLD
       Lisp_Object symbol;
       pid_t pid = p->pid;
 
@@ -820,7 +817,6 @@
 	deleted_pid_list
 	  = Fdelete (make_fixnum_or_float (pid), deleted_pid_list);
       else
-#endif
 	{
 	  Fkill_process (process, Qnil);
 	  /* Do this now, since remove_process will make the
@@ -1578,9 +1574,7 @@
 #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;
@@ -1677,13 +1671,11 @@
 
   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 ();
@@ -1791,10 +1783,8 @@
       /* 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);
@@ -1815,9 +1805,7 @@
     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)
@@ -4609,7 +4597,7 @@
 		 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 ();
@@ -4807,10 +4795,8 @@
 #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.  */
@@ -5673,7 +5659,7 @@
 
    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,
@@ -5811,7 +5797,7 @@
   if (!NILP (current_group))
     {
       if (ioctl (p->infd, TIOCSIGSEND, signo) == -1)
-	EMACS_KILLPG (gid, signo);
+	kill (-gid, signo);
     }
   else
     {
@@ -5819,7 +5805,7 @@
       kill (gid, signo);
     }
 #else /* ! defined (TIOCSIGSEND) */
-  EMACS_KILLPG (gid, signo);
+  kill (-gid, signo);
 #endif /* ! defined (TIOCSIGSEND) */
 }
 
@@ -5934,6 +5920,7 @@
   (Lisp_Object process, Lisp_Object sigcode)
 {
   pid_t pid;
+  int signo;
 
   if (STRINGP (process))
     {
@@ -5963,12 +5950,11 @@
 	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;
@@ -5976,96 +5962,12 @@
       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,
@@ -6201,7 +6103,6 @@
 void
 record_child_status_change (pid_t pid, int w)
 {
-#ifdef SIGCHLD
 
   /* Record at most one child only if we already know one child that
      has exited.  */
@@ -6290,11 +6191,8 @@
       if (input_available_clear_time)
 	*input_available_clear_time = make_emacs_time (0, 0);
     }
-#endif
 }
 
-#ifdef SIGCHLD
-
 static void
 handle_child_signal (int sig)
 {
@@ -6306,8 +6204,6 @@
 {
   deliver_process_signal (sig, handle_child_signal);
 }
-
-#endif /* SIGCHLD */
 
 
 static Lisp_Object
@@ -7156,7 +7052,6 @@
 
   inhibit_sentinels = 0;
 
-#ifdef SIGCHLD
 #ifndef CANNOT_DUMP
   if (! noninteractive || initialized)
 #endif
@@ -7165,7 +7060,6 @@
       emacs_sigaction_init (&action, deliver_child_signal);
       sigaction (SIGCHLD, &action, 0);
     }
-#endif
 
   FD_ZERO (&input_wait_mask);
   FD_ZERO (&non_keyboard_wait_mask);
@@ -7192,9 +7086,7 @@
 #endif
 
   Vprocess_alist = Qnil;
-#ifdef SIGCHLD
   deleted_pid_list = Qnil;
-#endif
   for (i = 0; i < MAXDESC; i++)
     {
       chan_process[i] = Qnil;
@@ -7321,9 +7213,7 @@
   DEFSYM (Qlast_nonmenu_event, "last-nonmenu-event");
 
   staticpro (&Vprocess_alist);
-#ifdef SIGCHLD
   staticpro (&deleted_pid_list);
-#endif
 
 #endif	/* subprocesses */

=== modified file 'src/sysdep.c'
--- src/sysdep.c	2012-11-27 03:10:32 +0000
+++ src/sysdep.c	2012-12-03 01:24:25 +0000
@@ -34,6 +34,7 @@
 #include <c-ctype.h>
 #include <careadlinkat.h>
 #include <ignore-value.h>
+#include <sig2str.h>
 #include <utimens.h>
 
 #include "lisp.h"
@@ -428,20 +429,15 @@
 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.  */
@@ -1491,9 +1487,7 @@
   /* 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
@@ -1654,6 +1648,27 @@
     sigaction (sig, &process_fatal_action, 0);
 }
 
+/* Return the integer value of the signal whose abbreviation is ABBR,
+   or a negative number if there is no such signal.  */
+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;
+}
+
 void
 init_signals (bool dumping)
 {
@@ -1673,18 +1688,11 @@
 # 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
@@ -1704,9 +1712,7 @@
 # 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
@@ -1718,9 +1724,7 @@
 # ifdef SIGIOT
       sys_siglist[SIGIOT] = "IOT trap";
 # endif
-# ifdef SIGKILL
       sys_siglist[SIGKILL] = "Killed";
-# endif
 # ifdef SIGLOST
       sys_siglist[SIGLOST] = "Resource lost";
 # endif
@@ -1733,9 +1737,7 @@
 # ifdef SIGPHONE
       sys_siglist[SIGWIND] = "SIGPHONE";
 # endif
-# ifdef SIGPIPE
       sys_siglist[SIGPIPE] = "Broken pipe";
-# endif
 # ifdef SIGPOLL
       sys_siglist[SIGPOLL] = "Pollable event occurred";
 # endif
@@ -1748,9 +1750,7 @@
 # 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

=== modified file 'src/syssignal.h'
--- src/syssignal.h	2012-10-07 02:26:03 +0000
+++ src/syssignal.h	2012-12-03 01:24:25 +0000
@@ -20,6 +20,7 @@
 #include <signal.h>
 #include <stdbool.h>
 
+extern int abbr_to_signal (char const *);
 extern void init_signals (bool);
 
 #ifdef HAVE_PTHREAD
@@ -54,26 +55,6 @@
 # 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

=== modified file 'src/w32proc.c'
--- src/w32proc.c	2012-11-27 03:10:32 +0000
+++ src/w32proc.c	2012-11-29 06:46:35 +0000
@@ -2139,6 +2139,10 @@
   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)
     {