From 1795be71fb9db24aaa5d3ef2fd71f0f952ccb72f Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Tue, 14 Nov 2006 20:22:12 +0000
Subject: [PATCH] Don't assume SIGPIPE exists, and that sigblock and sigsetmask
 exist if sigprocmask does not.  Problem reported by Paul Edwards for MVS 3.8.
 * configure.ac (sigblock): Check whether this function is available, if
 sigprocmask is not. * src/sdiff.c (sigs): Omit SIGPIPE if it's not defined.
 Put SIGINT last; all uses changed. (handler_index_of_SIGPIPE): Omit if
 SIGPIPE is not defined. (sigblock, sigsetmask) [!HAVE_SIGBLOCK]: New macros.

---
 ChangeLog    | 12 ++++++++++++
 configure.ac |  3 +++
 src/sdiff.c  | 14 ++++++++++----
 3 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 4347dcb..bea73f5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2006-11-14  Paul Eggert  <eggert@cs.ucla.edu>
+
+	Don't assume SIGPIPE exists, and that sigblock and sigsetmask
+	exist if sigprocmask does not.  Problem reported by Paul Edwards
+	for MVS 3.8.
+	* configure.ac (sigblock): Check whether this function is
+	available, if sigprocmask is not.
+	* src/sdiff.c (sigs): Omit SIGPIPE if it's not defined.
+	Put SIGINT last; all uses changed.
+	(handler_index_of_SIGPIPE): Omit if SIGPIPE is not defined.
+	(sigblock, sigsetmask) [!HAVE_SIGBLOCK]: New macros.
+
 2006-11-04  Paul Eggert  <eggert@cs.ucla.edu>
 
 	* src/sdiff.c (sigprocmask) [! HAVE_SIGPROCMASK]: Cast 2nd arg to
diff --git a/configure.ac b/configure.ac
index d5769df..1da2748 100644
--- a/configure.ac
+++ b/configure.ac
@@ -54,6 +54,9 @@ AC_HEADER_SYS_WAIT
 AC_TYPE_PID_T
 
 AC_CHECK_FUNCS_ONCE([sigaction sigprocmask strcasecoll stricoll])
+if test $ac_cv_func_sigprocmask = no; then
+  AC_CHECK_FUNCS([sigblock])
+fi
 AC_FUNC_CLOSEDIR_VOID
 AC_FUNC_FORK
 
diff --git a/src/sdiff.c b/src/sdiff.c
index 8f53762..ab57e39 100644
--- a/src/sdiff.c
+++ b/src/sdiff.c
@@ -81,11 +81,13 @@ static int const sigs[] = {
 #ifdef SIGXFSZ
        SIGXFSZ,
 #endif
-       SIGINT,
-       SIGPIPE
+#ifdef SIGPIPE
+       SIGPIPE,
+# define handler_index_of_SIGPIPE (NUM_SIGS - 2)
+#endif
+       SIGINT
+#define handler_index_of_SIGINT (NUM_SIGS - 1)
 };
-#define handler_index_of_SIGINT (NUM_SIGS - 2)
-#define handler_index_of_SIGPIPE (NUM_SIGS - 1)
 
 #if HAVE_SIGACTION
   /* Prefer `sigaction' if available, since `signal' can lose signals.  */
@@ -111,6 +113,10 @@ static int const sigs[] = {
 # ifndef SIG_SETMASK
 #  define SIG_SETMASK (! SIG_BLOCK)
 # endif
+# if ! HAVE_SIGBLOCK
+#  define sigblock(mask) (mask)
+#  define sigsetmask(mask) (mask)
+# endif
 # define sigprocmask(how, n, o) \
     ((how) == SIG_BLOCK \
      ? *(sigset_t *) (o) = sigblock (*(n)) \