Re: _GL_CXXALIAS_SYS (raise, int, (int sig)); in signal.h may give complie error in C++ source.

[Bruno Haible]

Hi,

Tatsuro MATSUOKA wrote:
> In the bug tracker octave, in which gnulib components are used,
> _GL_CXXALIAS_SYS (raise, int, (int sig)); in signal.h seems to give compile
> error.
> 
> https://savannah.gnu.org/bugs/?34378
> 
> John W. Eaton said in comment #3 in the above tracker that
> 
> *********************************************
> I'm fairly sure this is a bug in gnulib, so needs to be fixed there. There
> shouldn't be two 
> 
> _GL_CXXALIAS_SYS (raise, int, (int sig));
> 
> lines in the libgnu/signal.h file

Thanks for the report. Yes, obviously this a mistake that I introduced on
2011-09-23. This patch fixes it:


2011-09-26  Bruno Haible  <address@hidden>

        raise: Fix double declaration with modules 'sigprocmask' and 'sigpipe'.
        * lib/signal.in.h (GNULIB_defined_signal_blocking): New macro.
        (raise): Remove older, duplicated declaration.
        (_gl_raise_SIGPIPE): New declaration.
        * lib/sigprocmask.c (_gl_raise_SIGPIPE): New function.
        (rpl_raise): Remove function.
        * lib/raise.c (rpl_raise, raise): Merge into a single function. Handle
        a gnulib-defined SIGPIPE here.
        * m4/raise.m4 (gl_FUNC_RAISE): Set REPLACE_RAISE also if the module
        'sigprocmask' has detected missing signal-blocking and the module
        'sigpipe' is enabled.
        Reported by Tatsuro MATSUOKA <address@hidden>.

--- lib/raise.c.orig    Wed Sep 28 00:43:41 2011
+++ lib/raise.c Tue Sep 27 22:15:23 2011
@@ -50,24 +50,30 @@
 
   return result;
 }
-#  define raise raise_nothrow
+# else
+#  define raise_nothrow raise
 # endif
 
-int
-rpl_raise (int sig)
-{
-  return raise_nothrow (sig);
-}
-
 #else
 /* An old Unix platform.  */
 
 # include <unistd.h>
 
+# define rpl_raise raise
+
+#endif
+
 int
-raise (int sig)
+rpl_raise (int sig)
 {
-  return kill (getpid (), sig);
-}
+#if GNULIB_defined_signal_blocking && GNULIB_defined_SIGPIPE
+  if (sig == SIGPIPE)
+    return _gl_raise_SIGPIPE ();
+#endif
 
+#if HAVE_RAISE
+  return raise_nothrow (sig);
+#else
+  return kill (getpid (), sig);
 #endif
+}
--- lib/signal.in.h.orig        Wed Sep 28 00:43:42 2011
+++ lib/signal.in.h     Tue Sep 27 22:09:27 2011
@@ -178,6 +178,10 @@
 #if @GNULIB_SIGPROCMASK@
 # if address@hidden@
 
+#  ifndef GNULIB_defined_signal_blocking
+#   define GNULIB_defined_signal_blocking 1
+#  endif
+
 /* Maximum signal number + 1.  */
 #  ifndef NSIG
 #   define NSIG 32
@@ -303,18 +307,10 @@
 # endif
 _GL_CXXALIASWARN (signal);
 
-/* Raise signal SIG.  */
 # if address@hidden@ && GNULIB_defined_SIGPIPE
-#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-#   undef raise
-#   define raise rpl_raise
-#  endif
-_GL_FUNCDECL_RPL (raise, int, (int sig));
-_GL_CXXALIAS_RPL (raise, int, (int sig));
-# else
-_GL_CXXALIAS_SYS (raise, int, (int sig));
+/* Raise signal SIGPIPE.  */
+_GL_EXTERN_C int _gl_raise_SIGPIPE (void);
 # endif
-_GL_CXXALIASWARN (raise);
 
 #elif defined GNULIB_POSIXCHECK
 # undef sigaddset
--- lib/sigprocmask.c.orig      Wed Sep 28 00:43:42 2011
+++ lib/sigprocmask.c   Tue Sep 27 21:54:35 2011
@@ -330,27 +330,19 @@
 }
 
 #if GNULIB_defined_SIGPIPE
-/* Raise the signal SIG.  */
+/* Raise the signal SIGPIPE.  */
 int
-rpl_raise (int sig)
-# undef raise
+_gl_raise_SIGPIPE (void)
 {
-  switch (sig)
+  if (blocked_set & (1U << SIGPIPE))
+    pending_array[SIGPIPE] = 1;
+  else
     {
-    case SIGPIPE:
-      if (blocked_set & (1U << sig))
-        pending_array[sig] = 1;
-      else
-        {
-          handler_t handler = SIGPIPE_handler;
-          if (handler == SIG_DFL)
-            exit (128 + SIGPIPE);
-          else if (handler != SIG_IGN)
-            (*handler) (sig);
-        }
-      return 0;
-    default: /* System defined signal */
-      return raise (sig);
+      handler_t handler = SIGPIPE_handler;
+      if (handler == SIG_DFL)
+        exit (128 + SIGPIPE);
+      else if (handler != SIG_IGN)
+        (*handler) (SIGPIPE);
     }
 }
 #endif
--- m4/raise.m4.orig    Wed Sep 28 00:43:42 2011
+++ m4/raise.m4 Tue Sep 27 22:03:30 2011
@@ -1,4 +1,4 @@
-# raise.m4 serial 1
+# raise.m4 serial 2
 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,
@@ -16,6 +16,17 @@
     if test $HAVE_MSVC_INVALID_PARAMETER_HANDLER = 1; then
       REPLACE_RAISE=1
     fi
+    m4_ifdef([gl_SIGNALBLOCKING], [
+      gl_SIGNALBLOCKING
+      if test $HAVE_POSIX_SIGNALBLOCKING = 0; then
+        m4_ifdef([gl_SIGNAL_SIGPIPE], [
+          gl_SIGNAL_SIGPIPE
+          if test $gl_cv_header_signal_h_SIGPIPE != yes; then
+            REPLACE_RAISE=1
+          fi
+        ], [:])
+      fi
+    ])
   fi
 ])
 

-- 
In memoriam Paul Eppstein <http://de.wikipedia.org/wiki/Paul_Eppstein>