Simplify Emacs part of pthread_sigmask support.

* Makefile.in (GNULIB_TOOL_FLAGS): Do not avoid sigprocmask.
* configure.in (AC_TYPE_UID_T): New dummy macro.
Configure gnulib after adjusting LIBS,
so that gnulib can assume the libraries in LIBS.
* lib/pthread_sigmask.c, lib/sigprocmask.c, m4/signalblocking.m4:
New files, automatically imported from gnulib.
* lib/gnulib.mk, m4/gl-comp.m4: Regenerate.
* src/Makefile.in (LIB_PTHREAD_SIGMASK): New macro.
(LIBES): Use it.

5 files changed, 164 insertions, 49 deletions

diff --git a/m4/getopt.m4 b/m4/getopt.m4
index 4d8450ff907..7e49ddde9f6 100644
--- a/m4/getopt.m4
+++ b/m4/getopt.m4
@@ -1,4 +1,4 @@
-# getopt.m4 serial 35
+# getopt.m4 serial 38
 dnl Copyright (C) 2002-2006, 2008-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -89,15 +89,15 @@ AC_DEFUN([gl_GETOPT_CHECK_HEADERS],
     AC_CACHE_CHECK([whether getopt is POSIX compatible],
       [gl_cv_func_getopt_posix],
       [
-        dnl BSD getopt_long uses an incompatible method to reset
-        dnl option processing.  Existence of the variable, in and of
+        dnl BSD getopt_long uses an incompatible method to reset option
+        dnl processing.  Existence of the optreset variable, in and of
         dnl itself, is not a reason to replace getopt, but knowledge
         dnl of the variable is needed to determine how to reset and
         dnl whether a reset reparses the environment.  Solaris
         dnl supports neither optreset nor optind=0, but keeps no state
         dnl that needs a reset beyond setting optind=1; detect Solaris
         dnl by getopt_clip.
-        AC_COMPILE_IFELSE(
+        AC_LINK_IFELSE(
           [AC_LANG_PROGRAM(
              [[#include <unistd.h>]],
              [[int *p = &optreset; return optreset;]])],
@@ -121,22 +121,20 @@ int
 main ()
 {
   {
-    int argc = 0;
-    char *argv[10];
+    static char program[] = "program";
+    static char a[] = "-a";
+    static char foo[] = "foo";
+    static char bar[] = "bar";
+    char *argv[] = { program, a, foo, bar, NULL };
     int c;
 
-    argv[argc++] = "program";
-    argv[argc++] = "-a";
-    argv[argc++] = "foo";
-    argv[argc++] = "bar";
-    argv[argc] = NULL;
     optind = OPTIND_MIN;
     opterr = 0;
 
-    c = getopt (argc, argv, "ab");
+    c = getopt (4, argv, "ab");
     if (!(c == 'a'))
       return 1;
-    c = getopt (argc, argv, "ab");
+    c = getopt (4, argv, "ab");
     if (!(c == -1))
       return 2;
     if (!(optind == 2))
@@ -144,22 +142,20 @@ main ()
   }
   /* Some internal state exists at this point.  */
   {
-    int argc = 0;
-    char *argv[10];
+    static char program[] = "program";
+    static char donald[] = "donald";
+    static char p[] = "-p";
+    static char billy[] = "billy";
+    static char duck[] = "duck";
+    static char a[] = "-a";
+    static char bar[] = "bar";
+    char *argv[] = { program, donald, p, billy, duck, a, bar, NULL };
     int c;
 
-    argv[argc++] = "program";
-    argv[argc++] = "donald";
-    argv[argc++] = "-p";
-    argv[argc++] = "billy";
-    argv[argc++] = "duck";
-    argv[argc++] = "-a";
-    argv[argc++] = "bar";
-    argv[argc] = NULL;
     optind = OPTIND_MIN;
     opterr = 0;
 
-    c = getopt (argc, argv, "+abp:q:");
+    c = getopt (7, argv, "+abp:q:");
     if (!(c == -1))
       return 4;
     if (!(strcmp (argv[0], "program") == 0))
@@ -181,7 +177,9 @@ main ()
   }
   /* Detect MacOS 10.5, AIX 7.1 bug.  */
   {
-    char *argv[3] = { "program", "-ab", NULL };
+    static char program[] = "program";
+    static char ab[] = "-ab";
+    char *argv[3] = { program, ab, NULL };
     optind = OPTIND_MIN;
     opterr = 0;
     if (getopt (2, argv, "ab:") != 'a')
@@ -239,19 +237,22 @@ dnl is ambiguous with environment values that contain newlines.
                 and fails on MacOS X 10.5, AIX 5.2, HP-UX 11, IRIX 6.5,
                 OSF/1 5.1, Solaris 10.  */
              {
-               char *myargv[3];
-               myargv[0] = "conftest";
-               myargv[1] = "-+";
-               myargv[2] = 0;
+               static char conftest[] = "conftest";
+               static char plus[] = "-+";
+               char *argv[3] = { conftest, plus, NULL };
                opterr = 0;
-               if (getopt (2, myargv, "+a") != '?')
+               if (getopt (2, argv, "+a") != '?')
                  result |= 1;
              }
              /* This code succeeds on glibc 2.8, mingw,
                 and fails on MacOS X 10.5, OpenBSD 4.0, AIX 5.2, HP-UX 11,
                 IRIX 6.5, OSF/1 5.1, Solaris 10, Cygwin 1.5.x.  */
              {
-               char *argv[] = { "program", "-p", "foo", "bar", NULL };
+               static char program[] = "program";
+               static char p[] = "-p";
+               static char foo[] = "foo";
+               static char bar[] = "bar";
+               char *argv[] = { program, p, foo, bar, NULL };
 
                optind = 1;
                if (getopt (4, argv, "p::") != 'p')
@@ -265,7 +266,10 @@ dnl is ambiguous with environment values that contain newlines.
              }
              /* This code succeeds on glibc 2.8 and fails on Cygwin 1.7.0.  */
              {
-               char *argv[] = { "program", "foo", "-p", NULL };
+               static char program[] = "program";
+               static char foo[] = "foo";
+               static char p[] = "-p";
+               char *argv[] = { program, foo, p, NULL };
                optind = 0;
                if (getopt (3, argv, "-p") != 1)
                  result |= 16;
@@ -274,13 +278,26 @@ dnl is ambiguous with environment values that contain newlines.
              }
              /* This code fails on glibc 2.11.  */
              {
-               char *argv[] = { "program", "-b", "-a", NULL };
+               static char program[] = "program";
+               static char b[] = "-b";
+               static char a[] = "-a";
+               char *argv[] = { program, b, a, NULL };
                optind = opterr = 0;
                if (getopt (3, argv, "+:a:b") != 'b')
                  result |= 64;
                else if (getopt (3, argv, "+:a:b") != ':')
                  result |= 64;
              }
+             /* This code dumps core on glibc 2.14.  */
+             {
+               static char program[] = "program";
+               static char w[] = "-W";
+               static char dummy[] = "dummy";
+               char *argv[] = { program, w, dummy, NULL };
+               optind = opterr = 1;
+               if (getopt (3, argv, "W;") != 'W')
+                 result |= 128;
+             }
              return result;
            ]])],
         [gl_cv_func_getopt_gnu=yes],
diff --git a/m4/gl-comp.m4 b/m4/gl-comp.m4
index 004c01a10a0..6c94e373871 100644
--- a/m4/gl-comp.m4
+++ b/m4/gl-comp.m4
@@ -55,6 +55,7 @@ AC_DEFUN([gl_EARLY],
   # Code from module pthread_sigmask:
   # Code from module readlink:
   # Code from module signal:
+  # Code from module sigprocmask:
   # Code from module socklen:
   # Code from module ssize_t:
   # Code from module stat:
@@ -142,7 +143,10 @@ if test $REPLACE_MKTIME = 1; then
 fi
 gl_TIME_MODULE_INDICATOR([mktime])
 gl_MULTIARCH
-gl_PTHREAD_SIGMASK
+gl_FUNC_PTHREAD_SIGMASK
+if test $HAVE_PTHREAD_SIGMASK = 0 || test $REPLACE_PTHREAD_SIGMASK = 1; then
+  AC_LIBOBJ([pthread_sigmask])
+fi
 gl_SIGNAL_MODULE_INDICATOR([pthread_sigmask])
 gl_FUNC_READLINK
 if test $HAVE_READLINK = 0 || test $REPLACE_READLINK = 1; then
@@ -184,6 +188,7 @@ AC_REQUIRE([AC_C_INLINE])
 gl_UNISTD_H
   gl_gnulib_enabled_dosname=false
   gl_gnulib_enabled_be453cec5eecf5731a274f2de7f2db36=false
+  gl_gnulib_enabled_sigprocmask=false
   gl_gnulib_enabled_stat=false
   gl_gnulib_enabled_strtoull=false
   gl_gnulib_enabled_verify=false
@@ -201,6 +206,18 @@ AC_SUBST([LTLIBINTL])
       gl_gnulib_enabled_be453cec5eecf5731a274f2de7f2db36=true
     fi
   }
+  func_gl_gnulib_m4code_sigprocmask ()
+  {
+    if ! $gl_gnulib_enabled_sigprocmask; then
+gl_SIGNALBLOCKING
+if test $HAVE_POSIX_SIGNALBLOCKING = 0; then
+  AC_LIBOBJ([sigprocmask])
+  gl_PREREQ_SIGPROCMASK
+fi
+gl_SIGNAL_MODULE_INDICATOR([sigprocmask])
+      gl_gnulib_enabled_sigprocmask=true
+    fi
+  }
   func_gl_gnulib_m4code_stat ()
   {
     if ! $gl_gnulib_enabled_stat; then
@@ -246,7 +263,7 @@ gl_STDLIB_MODULE_INDICATOR([strtoull])
   if test $REPLACE_LSTAT = 1; then
     func_gl_gnulib_m4code_stat
   fi
-  if test $REPLACE_PTHREAD_SIGMASK = 1; then
+  if test $HAVE_PTHREAD_SIGMASK = 0 || test $REPLACE_PTHREAD_SIGMASK = 1; then
     func_gl_gnulib_m4code_sigprocmask
   fi
   if test $HAVE_READLINK = 0 || test $REPLACE_READLINK = 1; then
@@ -261,6 +278,7 @@ gl_STDLIB_MODULE_INDICATOR([strtoull])
   m4_pattern_allow([^gl_GNULIB_ENABLED_])
   AM_CONDITIONAL([gl_GNULIB_ENABLED_dosname], [$gl_gnulib_enabled_dosname])
   AM_CONDITIONAL([gl_GNULIB_ENABLED_be453cec5eecf5731a274f2de7f2db36], [$gl_gnulib_enabled_be453cec5eecf5731a274f2de7f2db36])
+  AM_CONDITIONAL([gl_GNULIB_ENABLED_sigprocmask], [$gl_gnulib_enabled_sigprocmask])
   AM_CONDITIONAL([gl_GNULIB_ENABLED_stat], [$gl_gnulib_enabled_stat])
   AM_CONDITIONAL([gl_GNULIB_ENABLED_strtoull], [$gl_gnulib_enabled_strtoull])
   AM_CONDITIONAL([gl_GNULIB_ENABLED_verify], [$gl_gnulib_enabled_verify])
@@ -434,6 +452,7 @@ AC_DEFUN([gl_FILE_LIST], [
   lib/md5.h
   lib/mktime-internal.h
   lib/mktime.c
+  lib/pthread_sigmask.c
   lib/readlink.c
   lib/sha1.c
   lib/sha1.h
@@ -442,6 +461,7 @@ AC_DEFUN([gl_FILE_LIST], [
   lib/sha512.c
   lib/sha512.h
   lib/signal.in.h
+  lib/sigprocmask.c
   lib/stat.c
   lib/stdarg.in.h
   lib/stdbool.in.h
@@ -485,6 +505,7 @@ AC_DEFUN([gl_FILE_LIST], [
   m4/sha256.m4
   m4/sha512.m4
   m4/signal_h.m4
+  m4/signalblocking.m4
   m4/socklen.m4
   m4/ssize_t.m4
   m4/st_dm_mode.m4
diff --git a/m4/pthread_sigmask.m4 b/m4/pthread_sigmask.m4
index d25e2cc3e70..dfa0f660a75 100644
--- a/m4/pthread_sigmask.m4
+++ b/m4/pthread_sigmask.m4
@@ -1,26 +1,77 @@
-# pthread_sigmask.m4 serial 2
+# pthread_sigmask.m4 serial 7
 dnl Copyright (C) 2011 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_PTHREAD_SIGMASK],
+AC_DEFUN([gl_FUNC_PTHREAD_SIGMASK],
 [
+  AC_CHECK_FUNCS_ONCE([pthread_sigmask])
+  LIB_PTHREAD_SIGMASK=
   m4_ifdef([gl_THREADLIB], [
     AC_REQUIRE([gl_THREADLIB])
     if test "$gl_threads_api" = posix; then
-      gl_save_LIBS="$LIBS"
-      LIBS="$LIBS $LIBMULTITHREAD"
-      AC_CHECK_FUNCS([pthread_sigmask])
-      LIBS="$gl_save_LIBS"
+      if test $ac_cv_func_pthread_sigmask = yes; then
+        dnl pthread_sigmask is available without -lpthread.
+        :
+      else
+        if test -n "$LIBMULTITHREAD"; then
+          AC_CACHE_CHECK([for pthread_sigmask in $LIBMULTITHREAD],
+            [gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD],
+            [gl_save_LIBS="$LIBS"
+             LIBS="$LIBS $LIBMULTITHREAD"
+             AC_LINK_IFELSE(
+               [AC_LANG_PROGRAM(
+                  [[#include <pthread.h>
+                    #include <signal.h>
+                  ]],
+                  [[return pthread_sigmask (0, (sigset_t *) 0, (sigset_t *) 0);]])
+               ],
+               [gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD=yes],
+               [gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD=no])
+             LIBS="$gl_save_LIBS"
+            ])
+          if test $gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD = yes; then
+            dnl pthread_sigmask is available with -lpthread.
+            LIB_PTHREAD_SIGMASK="$LIBMULTITHREAD"
+          else
+            dnl pthread_sigmask is not available at all.
+            HAVE_PTHREAD_SIGMASK=0
+          fi
+        else
+          dnl pthread_sigmask is not available at all.
+          HAVE_PTHREAD_SIGMASK=0
+        fi
+      fi
     else
-      ac_cv_func_pthread_sigmask=no
+      dnl pthread_sigmask may exist but does not interoperate with the chosen
+      dnl multithreading facility.
+      dnl If "$gl_threads_api" = pth, we could use the function pth_sigmask,
+      dnl but it is equivalent to sigprocmask, so we choose to emulate
+      dnl pthread_sigmask with sigprocmask also in this case. This yields fewer
+      dnl link dependencies.
+      if test $ac_cv_func_pthread_sigmask = yes; then
+        REPLACE_PTHREAD_SIGMASK=1
+      else
+        HAVE_PTHREAD_SIGMASK=0
+      fi
+    fi
+  ] ,[
+    dnl gl_THREADLIB is not in use.  Assume the application wants
+    dnl POSIX semantics.
+    if test $ac_cv_func_pthread_sigmask != yes; then
+      gl_save_LIBS=$LIBS
+      AC_SEARCH_LIBS([pthread_sigmask], [pthread c_r])
+      LIBS=$gl_save_LIBS
+      if test "$ac_cv_search_pthread_sigmask" = no; then
+        HAVE_PTHREAD_SIGMASK=0
+      elif test "$ac_cv_search_pthread_sigmask" != 'none required'; then
+        LIB_PTHREAD_SIGMASK=$ac_cv_search_pthread_sigmask
+      fi
     fi
-  ], [
-    AC_CHECK_FUNCS_ONCE([pthread_sigmask])
   ])
-
-  if test $ac_cv_func_pthread_sigmask = no; then
-    REPLACE_PTHREAD_SIGMASK=1
-  fi
+  AC_SUBST([LIB_PTHREAD_SIGMASK])
+  dnl We don't need a variable LTLIB_PTHREAD_SIGMASK, because when
+  dnl "$gl_threads_api" = posix, $LTLIBMULTITHREAD and $LIBMULTITHREAD are the
+  dnl same: either both empty or both "-lpthread".
 ])
diff --git a/m4/signal_h.m4 b/m4/signal_h.m4
index 53972fba54f..b9536fb0e3c 100644
--- a/m4/signal_h.m4
+++ b/m4/signal_h.m4
@@ -1,4 +1,4 @@
-# signal_h.m4 serial 14
+# signal_h.m4 serial 16
 dnl Copyright (C) 2007-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -64,6 +64,7 @@ AC_DEFUN([gl_SIGNAL_H_DEFAULTS],
   GNULIB_SIGACTION=0;          AC_SUBST([GNULIB_SIGACTION])
   dnl Assume proper GNU behavior unless another module says otherwise.
   HAVE_POSIX_SIGNALBLOCKING=1; AC_SUBST([HAVE_POSIX_SIGNALBLOCKING])
+  HAVE_PTHREAD_SIGMASK=1;      AC_SUBST([HAVE_PTHREAD_SIGMASK])
   HAVE_SIGSET_T=1;             AC_SUBST([HAVE_SIGSET_T])
   HAVE_SIGINFO_T=1;            AC_SUBST([HAVE_SIGINFO_T])
   HAVE_SIGACTION=1;            AC_SUBST([HAVE_SIGACTION])
diff --git a/m4/signalblocking.m4 b/m4/signalblocking.m4
new file mode 100644
index 00000000000..15b74253ba6
--- /dev/null
+++ b/m4/signalblocking.m4
@@ -0,0 +1,25 @@
+# signalblocking.m4 serial 12
+dnl Copyright (C) 2001-2002, 2006-2011 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.
+
+# Determine available signal blocking primitives. Three different APIs exist:
+# 1) POSIX: sigemptyset, sigaddset, sigprocmask
+# 2) SYSV: sighold, sigrelse
+# 3) BSD: sigblock, sigsetmask
+# For simplicity, here we check only for the POSIX signal blocking.
+AC_DEFUN([gl_SIGNALBLOCKING],
+[
+  AC_REQUIRE([gl_SIGNAL_H_DEFAULTS])
+  AC_REQUIRE([gl_CHECK_TYPE_SIGSET_T])
+  if test $gl_cv_type_sigset_t = yes; then
+    AC_CHECK_FUNC([sigprocmask], [gl_cv_func_sigprocmask=1])
+  fi
+  if test -z "$gl_cv_func_sigprocmask"; then
+    HAVE_POSIX_SIGNALBLOCKING=0
+  fi
+])
+
+# Prerequisites of lib/sigprocmask.c.
+AC_DEFUN([gl_PREREQ_SIGPROCMASK], [:])