From a5d1e89bde3696e7891b3298fd806cd52a164653 Mon Sep 17 00:00:00 2001
From: Roland McGrath <roland@gnu.org>
Date: Mon, 9 Dec 2002 02:03:15 +0000
Subject: [PATCH] 2001-10-20  Paul Eggert  <eggert@twinsun.com>

	* misc/error.c (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.
---
 misc/error.c | 76 ++++++++++++++++++++++++++++++++++++----------------
 1 file changed, 53 insertions(+), 23 deletions(-)

diff --git a/misc/error.c b/misc/error.c
index 0e12297001..5463f17c42 100644
--- a/misc/error.c
+++ b/misc/error.c
@@ -88,7 +88,7 @@ extern void __error_at_line (int status, int errnum, const char *file_name,
 # define error_at_line __error_at_line
 
 # ifdef USE_IN_LIBIO
-# include <libio/iolibio.h>
+#  include <libio/iolibio.h>
 #  define fflush(s) INTUSE(_IO_fflush) (s)
 #  undef putc
 #  define putc(c, fp) INTUSE(_IO_putc) (c, fp)
@@ -96,21 +96,30 @@ 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;
@@ -121,9 +130,43 @@ 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
@@ -180,25 +223,12 @@ 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);
+    print_errno_message (errnum);
 # 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
-    }
-#if _LIBC && USE_IN_LIBIO
   if (_IO_fwide (stderr, 0) > 0)
     putwc (L'\n', stderr);
   else
-#endif
+# endif
     putc ('\n', stderr);
   fflush (stderr);
   if (status)
@@ -255,7 +285,7 @@ error (status, errnum, message, va_alist)
 
   ++error_message_count;
   if (errnum)
-    fprintf (stderr, ": %s", strerror (errnum));
+    print_errno_message (errnum);
   putc ('\n', stderr);
   fflush (stderr);
   if (status)
@@ -346,7 +376,7 @@ error_at_line (status, errnum, file_name, line_number, message, va_alist)
 
   ++error_message_count;
   if (errnum)
-    fprintf (stderr, ": %s", strerror (errnum));
+    print_errno_message (errnum);
   putc ('\n', stderr);
   fflush (stderr);
   if (status)
-- 
2.43.5