pthread_sigmask: Make declaration C++ safe.

[gnulib.git] / lib / signal.in.h

diff --git a/lib/signal.in.h b/lib/signal.in.h
index 5049b1d..6d1be8f 100644 (file)
--- a/lib/signal.in.h
+++ b/lib/signal.in.h
@@ -20,8 +20,17 @@
 #endif
 @PRAGMA_COLUMNS@
 
-#if defined __need_sig_atomic_t || defined __need_sigset_t
-/* Special invocation convention inside glibc header files.  */
+#if defined __need_sig_atomic_t || defined __need_sigset_t || defined _GL_ALREADY_INCLUDING_SIGNAL_H || (defined _SIGNAL_H && !defined __SIZEOF_PTHREAD_MUTEX_T)
+/* Special invocation convention:
+   - Inside glibc header files.
+   - On glibc systems we have a sequence of nested includes
+     <signal.h> -> <ucontext.h> -> <signal.h>.
+     In this situation, the functions are not yet declared, therefore we cannot
+     provide the C++ aliases.
+   - On glibc systems with GCC 4.3 we have a sequence of nested includes
+     <csignal> -> </usr/include/signal.h> -> <sys/ucontext.h> -> <signal.h>.
+     In this situation, some of the functions are not yet declared, therefore
+     we cannot provide the C++ aliases.  */
 
 # @INCLUDE_NEXT@ @NEXT_SIGNAL_H@
 
@@ -30,6 +39,8 @@
 
 #ifndef _@GUARD_PREFIX@_SIGNAL_H
 
+#define _GL_ALREADY_INCLUDING_SIGNAL_H
+
 /* Define pid_t, uid_t.
    Also, mingw defines sigset_t not in <signal.h>, but in <sys/types.h>.
    On Solaris 10, <signal.h> includes <sys/types.h>, which eventually includes
@@ -39,6 +50,8 @@
 /* The include_next requires a split double-inclusion guard.  */
 #@INCLUDE_NEXT@ @NEXT_SIGNAL_H@
 
+#undef _GL_ALREADY_INCLUDING_SIGNAL_H
+
 #ifndef _@GUARD_PREFIX@_SIGNAL_H
 #define _@GUARD_PREFIX@_SIGNAL_H
 
@@ -103,10 +116,13 @@ typedef void (*sighandler_t) (int);
 
 
 #if @GNULIB_PTHREAD_SIGMASK@
-# if @REPLACE_PTHREAD_SIGMASK@
+# if !@HAVE_PTHREAD_SIGMASK@
 _GL_FUNCDECL_SYS (pthread_sigmask, int,
                   (int how, const sigset_t *new_mask, sigset_t *old_mask));
 # endif
+_GL_CXXALIAS_SYS (pthread_sigmask, int,
+                  (int how, const sigset_t *new_mask, sigset_t *old_mask));
+_GL_CXXALIASWARN (pthread_sigmask);
 #elif defined GNULIB_POSIXCHECK
 # undef pthread_sigmask
 # if HAVE_RAW_DECL_PTHREAD_SIGMASK