Replace strsignal if it does not work fine.

diff --git a/ChangeLog b/ChangeLog
index 7baf920a9047dd5d1d7df90e976ce61e8aa1f107..0e594bd6f0272d685be16b091a2894e3df4c9dcf 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2008-01-14  Colin Watson  <cjwatson@debian.org>
+            Bruno Haible  <bruno@clisp.org>
+
+       * m4/strsignal.m4 (gl_FUNC_STRSIGNAL): Also check whether strsignal
+       works fine; if not, set REPLACE_STRSIGNAL.
+       (gl_PREREQ_STRSIGNAL): Require AC_DECL_SYS_SIGLIST.
+       * m4/string_h.m4 (gl_HEADER_STRING_H_DEFAULTS): Initialize
+       REPLACE_STRSIGNAL.
+       * lib/string.in.h (strsignal): Consider REPLACE_STRSIGNAL.
+       * modules/string (Makefile.am): Substitute REPLACE_STRSIGNAL.
+       * tests/test-strsignal.c (main): Check out-of-range signal numbers.
+
 2008-01-14  Bruno Haible  <bruno@clisp.org>
 
        * modules/strsignal (Include): Change to <string.h>.

diff --git a/lib/string.in.h b/lib/string.in.h
index 3354d209229d34e560d928ca5380bae846969fab..7e6bd088e8d1fe4fcbf8775ab45ccbc58abdf85b 100644 (file)
--- a/lib/string.in.h
+++ b/lib/string.in.h
@@ -542,7 +542,10 @@ extern char *strerror (int);
 #endif
 
 #if @GNULIB_STRSIGNAL@
-# if ! @HAVE_DECL_STRSIGNAL@
+# if @REPLACE_STRSIGNAL@
+#  define strsignal rpl_strsignal
+# endif
+# if ! @HAVE_DECL_STRSIGNAL@ || @REPLACE_STRSIGNAL@
 extern char *strsignal (int __sig);
 # endif
 #elif defined GNULIB_POSIXCHECK

diff --git a/m4/string_h.m4 b/m4/string_h.m4
index 69761d720d332ac94373a55e6783a30c90319723..02202b695c4cdf6bbee133f43a7f3cffab0c1dfd 100644 (file)
--- a/m4/string_h.m4
+++ b/m4/string_h.m4
@@ -5,7 +5,7 @@
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
 
-# serial 3
+# serial 4
 
 # Written by Paul Eggert.
 
@@ -80,6 +80,7 @@ AC_DEFUN([gl_HEADER_STRING_H_DEFAULTS],
   HAVE_DECL_STRERROR=1;                AC_SUBST([HAVE_DECL_STRERROR])
   HAVE_DECL_STRSIGNAL=1;       AC_SUBST([HAVE_DECL_STRSIGNAL])
   REPLACE_STRERROR=0;          AC_SUBST([REPLACE_STRERROR])
+  REPLACE_STRSIGNAL=0;         AC_SUBST([REPLACE_STRSIGNAL])
   REPLACE_MEMMEM=0;            AC_SUBST([REPLACE_MEMMEM])
   REPLACE_STRSTR=0;            AC_SUBST([REPLACE_STRSTR])
 ])

diff --git a/m4/strsignal.m4 b/m4/strsignal.m4
index 9bcd374ac098f579118811d25c2adf2d718a030f..5244dcb6c126e12262234b63f43c85a550a55404 100644 (file)
--- a/m4/strsignal.m4
+++ b/m4/strsignal.m4
@@ -1,4 +1,4 @@
-# strsignal.m4 serial 1
+# strsignal.m4 serial 2
 dnl Copyright (C) 2008 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -9,16 +9,47 @@ AC_DEFUN([gl_FUNC_STRSIGNAL],
   dnl Persuade glibc <string.h> to declare strsignal().
   AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
 
-  AC_REQUIRE([AC_DECL_SYS_SIGLIST])
-
   AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])
-  AC_REPLACE_FUNCS([strsignal])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
   AC_CHECK_DECLS_ONCE([strsignal])
   if test $ac_cv_have_decl_strsignal = no; then
     HAVE_DECL_STRSIGNAL=0
+  fi
+
+  AC_CHECK_FUNCS([strsignal])
+  if test $ac_cv_func_strsignal = yes; then
+    dnl Check if strsignal behaves reasonably for out-of-range signal numbers.
+    dnl On Solaris it returns NULL; on AIX 5.1 it returns (char *) -1.
+    AC_CACHE_CHECK([whether strsignal always returns a string],
+      [gl_cv_func_working_strsignal],
+      [AC_RUN_IFELSE(
+        [AC_LANG_PROGRAM(
+           [[#include <string.h>
+           ]],
+           [[char *s = strsignal (-1);
+             return !(s != (char *) 0 && s != (char *) -1);]])],
+        [gl_cv_func_working_strsignal=yes],
+        [gl_cv_func_working_strsignal=no],
+        [case "$host_os" in
+           solaris* | aix*) gl_cv_func_working_strsignal=no;;
+           *)               gl_cv_func_working_strsignal="guessing yes";;
+         esac])])
+  else
+    gl_cv_func_working_strsignal=no
+  fi
+
+  if test "$gl_cv_func_working_strsignal" = no; then
+    if test $ac_cv_func_strsignal = yes; then
+      REPLACE_STRSIGNAL=1
+    fi
+    AC_LIBOBJ([strsignal])
     gl_PREREQ_STRSIGNAL
   fi
 ])
 
 # Prerequisites of lib/strsignal.c.
-AC_DEFUN([gl_PREREQ_STRSIGNAL], [:])
+AC_DEFUN([gl_PREREQ_STRSIGNAL], [
+  AC_REQUIRE([AC_DECL_SYS_SIGLIST])
+  :
+])

diff --git a/modules/string b/modules/string
index 0a2fd71ce46bdac2d99c99aa27e2a73a8e59c620..f59a11e3525dff5dd31a2516b0226b2a7640e904 100644 (file)
--- a/modules/string
+++ b/modules/string
@@ -72,6 +72,7 @@ string.h: string.in.h
              -e 's|@''REPLACE_MEMMEM''@|$(REPLACE_MEMMEM)|g' \
              -e 's|@''REPLACE_STRSTR''@|$(REPLACE_STRSTR)|g' \
              -e 's|@''REPLACE_STRERROR''@|$(REPLACE_STRERROR)|g' \
+             -e 's|@''REPLACE_STRSIGNAL''@|$(REPLACE_STRSIGNAL)|g' \
              -e '/definition of GL_LINK_WARNING/r $(LINK_WARNING_H)' \
              < $(srcdir)/string.in.h; \
        } > $@-t

diff --git a/tests/test-strsignal.c b/tests/test-strsignal.c
index 16544f209debb091d1479777dd39fccff37ada35..9bd8133e7d858684608bd1670a78cc02f6546ef9 100644 (file)
--- a/tests/test-strsignal.c
+++ b/tests/test-strsignal.c
@@ -65,5 +65,17 @@ main (int argc, char **argv)
   ASSERT_DESCRIPTION (str, "Interrupt");
 #endif
 
+  /* Test that for out-of-range signal numbers the result is usable.  */
+
+  str = strsignal (-1);
+  ASSERT (str);
+  ASSERT (str != (char *) -1);
+  ASSERT (strlen (str));
+
+  str = strsignal (9249234);
+  ASSERT (str);
+  ASSERT (str != (char *) -1);
+  ASSERT (strlen (str));
+
   return 0;
 }