From e5bf94ff351ef97da921c0c47b6a5ff9a405821d Mon Sep 17 00:00:00 2001
From: Jim Meyering <jim@meyering.net>
Date: Sun, 21 Oct 2001 07:59:04 +0000
Subject: [PATCH] (strerror_r): Do not declare unless !_LIBC. Do not check for
 HAVE_DECL_STRERROR_R missing unless STRERROR_R_CHAR_P. Use strerror_r that is
 only a macro, even if it is not a function. (strerror): Check for
 HAVE_DECL_STRERROR before declaring. (private_strerror): Use prototypes, not
 old-style function definition. (print_errno_message): New function. Support
 the POSIX 'int'-flavored strerror_r, as well as the traditional
 char*-flavored one. (error_tail, error, error_at_line): Use it.

---
 lib/error.c | 99 +++++++++++++++++++++++++++++++------------------------------
 1 file changed, 51 insertions(+), 48 deletions(-)

diff --git a/lib/error.c b/lib/error.c
index b85b76d32..9c0700c2e 100644
--- a/lib/error.c
+++ b/lib/error.c
@@ -55,13 +55,6 @@ void exit ();
 
 #include "error.h"
 
-#ifndef HAVE_DECL_STRERROR_R
-"this configure-time declaration test was not run"
-#endif
-#if !HAVE_DECL_STRERROR_R
-char *strerror_r ();
-#endif
-
 #ifndef _
 # define _(String) String
 #endif
@@ -102,21 +95,30 @@ extern void __error_at_line (int status, int errnum, const char *file_name,
 
 #else /* not _LIBC */
 
+# if !HAVE_DECL_STRERROR_R && STRERROR_R_CHAR_P
+#  ifndef HAVE_DECL_STRERROR_R
+"this configure-time declaration test was not run"
+#  endif
+char *strerror_r ();
+# endif
+
 /* The calling program should define program_name and set it to the
    name of the executing program.  */
 extern char *program_name;
 
-# ifdef HAVE_STRERROR_R
+# if HAVE_STRERROR_R || defined strerror_r
 #  define __strerror_r strerror_r
 # else
 #  if HAVE_STRERROR
-#   ifndef strerror		/* On some systems, strerror is a macro */
+#   ifndef HAVE_DECL_STRERROR
+"this configure-time declaration test was not run"
+#   endif
+#   if !HAVE_DECL_STRERROR
 char *strerror ();
 #   endif
 #  else
 static char *
-private_strerror (errnum)
-     int errnum;
+private_strerror (int errnum)
 {
   extern char *sys_errlist[];
   extern int sys_nerr;
@@ -127,9 +129,43 @@ private_strerror (errnum)
 }
 #   define strerror private_strerror
 #  endif /* HAVE_STRERROR */
-# endif	/* HAVE_STRERROR_R */
+# endif	/* HAVE_STRERROR_R || defined strerror_r */
 #endif	/* not _LIBC */
 
+static void
+print_errno_message (int errnum)
+{
+  char const *s;
+
+#if defined HAVE_STRERROR_R || _LIBC
+  char errbuf[1024];
+# if STRERROR_R_CHAR_P || _LIBC
+  s = __strerror_r (errnum, errbuf, sizeof errbuf);
+# else
+  if (__strerror_r (errnum, errbuf, sizeof errbuf) == 0)
+    s = errbuf;
+  else
+    s = 0;
+# endif
+#else
+  s = strerror (errnum);
+#endif
+
+#if !_LIBC
+  if (! s)
+    s = _("Unknown system error");
+#endif
+
+#if _LIBC && USE_IN_LIBIO
+  if (_IO_fwide (stderr, 0) > 0)
+    {
+      __fwprintf (stderr, L": %s", s);
+      return;
+    }
+#endif
+
+  fprintf (stderr, ": %s", s);
+}
 
 #ifdef VA_START
 static void
@@ -186,20 +222,7 @@ error_tail (int status, int errnum, const char *message, va_list args)
 
   ++error_message_count;
   if (errnum)
-    {
-# if defined HAVE_STRERROR_R || _LIBC
-      char errbuf[1024];
-      char *s = __strerror_r (errnum, errbuf, sizeof errbuf);
-#  if _LIBC && USE_IN_LIBIO
-      if (_IO_fwide (stderr, 0) > 0)
-	__fwprintf (stderr, L": %s", s);
-      else
-#  endif
-	fprintf (stderr, ": %s", s);
-# else
-      fprintf (stderr, ": %s", strerror (errnum));
-# endif
-    }
+    print_errno_message (errnum);
 # if _LIBC && USE_IN_LIBIO
   if (_IO_fwide (stderr, 0) > 0)
     putwc (L'\n', stderr);
@@ -261,17 +284,7 @@ error (status, errnum, message, va_alist)
 
   ++error_message_count;
   if (errnum)
-    {
-# if defined HAVE_STRERROR_R || _LIBC
-      char errbuf[1024];
-      /* Don't use __strerror_r's return value because on some systems
-	 (at least DEC UNIX 4.0[A-D]) strerror_r returns `int'.  */
-      __strerror_r (errnum, errbuf, sizeof errbuf);
-      fprintf (stderr, ": %s", errbuf);
-# else
-      fprintf (stderr, ": %s", strerror (errnum));
-# endif
-    }
+    print_errno_message (errnum);
   putc ('\n', stderr);
   fflush (stderr);
   if (status)
@@ -362,17 +375,7 @@ error_at_line (status, errnum, file_name, line_number, message, va_alist)
 
   ++error_message_count;
   if (errnum)
-    {
-# if defined HAVE_STRERROR_R || _LIBC
-      char errbuf[1024];
-      /* Don't use __strerror_r's return value because on some systems
-	 (at least DEC UNIX 4.0[A-D]) strerror_r returns `int'.  */
-      __strerror_r (errnum, errbuf, sizeof errbuf);
-      fprintf (stderr, ": %s", errbuf);
-# else
-      fprintf (stderr, ": %s", strerror (errnum));
-# endif
-    }
+    print_errno_message (errnum);
   putc ('\n', stderr);
   fflush (stderr);
   if (status)
-- 
2.11.0