Detect sys_sigabbrev[] and use it in place of sys_signame[] if

present.  For some reason glibc does not declare sys_sigabbrev so
we must add an extern definition of our own.

compat/strsigname.c

@@ -32,7 +32,13 @@
 # define sudo_sys_signame	_sys_signame
 #elif defined(HAVE_DECL___SYS_SIGNAME) && HAVE_DECL___SYS_SIGNAME == 1
 # define sudo_sys_signame	__sys_signame
+#elif defined(HAVE_DECL_SYS_SIGABBREV) && HAVE_DECL_SYS_SIGABBREV == 1
+# define sudo_sys_signame	sys_sigabbrev
 #else
+# ifdef HAVE_SYS_SIGABBREV
+   /* sys_sigabbrev is not declared by glibc */
+#  define sudo_sys_signame	sys_sigabbrev
+# endif
 extern const char *const sudo_sys_signame[NSIG];
 #endif
 

config.h.in

@@ -87,6 +87,10 @@
    don't. */
 #undef HAVE_DECL_H_ERRNO
 
+/* Define to 1 if you have the declaration of `sys_sigabbrev', and to 0 if you
+   don't. */
+#undef HAVE_DECL_SYS_SIGABBREV
+
 /* Define to 1 if you have the declaration of `sys_siglist', and to 0 if you
    don't. */
 #undef HAVE_DECL_SYS_SIGLIST
@@ -639,6 +643,9 @@
 /* Define to 1 if you have the <sys/select.h> header file. */
 #undef HAVE_SYS_SELECT_H
 
+/* Define to 1 if your libc has the `sys_sigabbrev' symbol. */
+#undef HAVE_SYS_SIGABBREV
+
 /* Define to 1 if you have the <sys/sockio.h> header file. */
 #undef HAVE_SYS_SOCKIO_H
 

configure

@@ -18385,15 +18385,69 @@ if test $ac_have_decl = 1; then :
 	HAVE_SIGNAME="true"
 	break
 
+fi
+ac_fn_c_check_decl "$LINENO" "sys_sigabbrev" "ac_cv_have_decl_sys_sigabbrev" "
+$ac_includes_default
+#include <signal.h>
+
+"
+if test "x$ac_cv_have_decl_sys_sigabbrev" = xyes; then :
+  ac_have_decl=1
+else
+  ac_have_decl=0
+fi
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_DECL_SYS_SIGABBREV $ac_have_decl
+_ACEOF
+if test $ac_have_decl = 1; then :
+
+	HAVE_SIGNAME="true"
+	break
+
 fi
 
     if test "$HAVE_SIGNAME" != "true"; then
-	case " $LIBOBJS " in
+	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for undeclared sys_sigabbrev" >&5
+$as_echo_n "checking for undeclared sys_sigabbrev... " >&6; }
+if ${sudo_cv_var_sys_sigabbrev+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+extern char **sys_sigabbrev;
+int
+main ()
+{
+return sys_sigabbrev[1];
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  sudo_cv_var_sys_sigabbrev=yes
+else
+  sudo_cv_var_sys_sigabbrev=no
+
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $sudo_cv_var_sys_sigabbrev" >&5
+$as_echo "$sudo_cv_var_sys_sigabbrev" >&6; }
+	if test "$sudo_cv_var_sys_sigabbrev" = yes; then
+	    $as_echo "#define HAVE_SYS_SIGABBREV 1" >>confdefs.h
+
+	else
+	    case " $LIBOBJS " in
   *" signame.$ac_objext "* ) ;;
   *) LIBOBJS="$LIBOBJS signame.$ac_objext"
  ;;
 esac
 
+	fi
     fi
 
 fi
@@ -23246,5 +23300,6 @@ fi
 
 
 
+
 
 

configure.in

@@ -2574,7 +2574,7 @@ dnl
 AC_CHECK_FUNCS(strsigname, [], [
     AC_LIBOBJ(strsigname)
     HAVE_SIGNAME="false"
-    AC_CHECK_DECLS([sys_signame, _sys_signame, __sys_signame], [
+    AC_CHECK_DECLS([sys_signame, _sys_signame, __sys_signame, sys_sigabbrev], [
 	HAVE_SIGNAME="true"
 	break
     ], [ ], [
@@ -2582,7 +2582,20 @@ AC_INCLUDES_DEFAULT
 #include <signal.h>
     ])
     if test "$HAVE_SIGNAME" != "true"; then
-	AC_LIBOBJ(signame)
+	AC_CACHE_CHECK([for undeclared sys_sigabbrev],
+	    [sudo_cv_var_sys_sigabbrev],
+	    [AC_LINK_IFELSE(
+		[AC_LANG_PROGRAM([[extern char **sys_sigabbrev;]], [[return sys_sigabbrev[1];]])],
+		    [sudo_cv_var_sys_sigabbrev=yes],
+		    [sudo_cv_var_sys_sigabbrev=no]
+		)
+	    ]
+	)
+	if test "$sudo_cv_var_sys_sigabbrev" = yes; then
+	    AC_DEFINE(HAVE_SYS_SIGABBREV)
+	else
+	    AC_LIBOBJ(signame)
+	fi
     fi
 ])
 
@@ -3627,6 +3640,7 @@ AH_TEMPLATE(RTLD_PRELOAD_ENABLE_VAR, [An extra environment variable that is requ
 AH_TEMPLATE(RTLD_PRELOAD_DELIM, [The delimiter to use when defining multiple preloaded objects.])
 AH_TEMPLATE(RTLD_PRELOAD_DEFAULT, [The default value of preloaded objects (if any).])
 AH_TEMPLATE(HAVE_DSO_VISIBILITY, [Define to 1 if the compiler supports the __visibility__ attribute.])
+AH_TEMPLATE(HAVE_SYS_SIGABBREV, [Define to 1 if your libc has the `sys_sigabbrev' symbol.])
 
 dnl
 dnl Bits to copy verbatim into config.h.in