Sync up error.c with gnulib

Summary of changes:

- Use of !_LIBC instead of HAVE_CONFIG_H
- Code changes in [!_LIBC] that don't affect us
- Minor formatting changes
- Use __builtin_expect in shared code
- Define some macros in [_LIBC] that are used in gnulib but never
  defined in glibc
- Flip macro check for STRERROR_R_CHAR_P so that it does not throw a
  warning

2 files changed, 103 insertions, 10 deletions

diff --git a/ChangeLog b/ChangeLog
index 7db7bdff0b..a1232aa215 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,22 @@
 2014-07-10  Siddhesh Poyarekar  <siddhesh@redhat.com>
 
+	Sync up with gnulib.
+	* misc/error.c: Use !_LIBC instead of HAVE_CONFIG_H.
+	[!_LIBC && ENABLE_NLS]: Include gettext.h.
+	[_LIBC]: Define USE_UNLOCKED_IO, _GL_ATTRIBUTE_FORMAT_PRINTF
+	and _GL_ARG_NONNULL.
+	[USE_UNLOCKED_IO]: Include unlocked-io.h.
+	[!_LIBC]: Include code for Windows and Cygwin.
+	[!_LIBC && !HAVE_DECL_STRERROR_R && !STRERROR_R_CHAR_P]:
+	Include prototype for int strerror_r.
+	[!_LIBC] (is_open): New function.
+	(flush_stdout): New function.
+	(print_errno_message): Use it.
+	(error): Likewise.
+	(error_at_line): Likewise.
+	(error_tail) Add function attribute macros.  Use
+	__builtin_expect.
+
 	* time/strptime_l.c [_LIBC]: Define HAVE_LOCALTIME_R.
 
 	* time/strftime_l.c [_LIBC]: Define HAVE_STRFTIME.
diff --git a/misc/error.c b/misc/error.c
index 63bd309f22..ee0cf86386 100644
--- a/misc/error.c
+++ b/misc/error.c
@@ -18,24 +18,36 @@
 
 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>.  */
 
-#ifdef HAVE_CONFIG_H
+#if !_LIBC
 # include <config.h>
 #endif
 
+#include "error.h"
+
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
+#if !_LIBC && ENABLE_NLS
+# include "gettext.h"
+# define _(msgid) gettext (msgid)
+#endif
+
 #ifdef _LIBC
 # include <libintl.h>
 # include <stdbool.h>
 # include <stdint.h>
 # include <wchar.h>
 # define mbsrtowcs __mbsrtowcs
+# define USE_UNLOCKED_IO 0
+# define _GL_ATTRIBUTE_FORMAT_PRINTF(a, b)
+# define _GL_ARG_NONNULL(a)
 #endif
 
-#include "error.h"
+#if USE_UNLOCKED_IO
+# include "unlocked-io.h"
+#endif
 
 #ifndef _
 # define _(String) String
@@ -46,7 +58,7 @@
    function without parameters instead.  */
 void (*error_print_progname) (void);
 
-/* This variable is incremented each time `error' is called.  */
+/* This variable is incremented each time 'error' is called.  */
 unsigned int error_message_count;
 
 #ifdef _LIBC
@@ -57,7 +69,7 @@ unsigned int error_message_count;
 # include <limits.h>
 # include <libio/libioP.h>
 
-/* In GNU libc we want do not want to use the common name `error' directly.
+/* In GNU libc we want do not want to use the common name 'error' directly.
    Instead make it a weak alias.  */
 extern void __error (int status, int errnum, const char *message, ...)
      __attribute__ ((__format__ (__printf__, 3, 4)));
@@ -77,11 +89,29 @@ 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
+# include <fcntl.h>
+# include <unistd.h>
+
+# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+/* Get declarations of the native Windows API functions.  */
+#  define WIN32_LEAN_AND_MEAN
+#  include <windows.h>
+/* Get _get_osfhandle.  */
+#  include "msvc-nothrow.h"
+# endif
+
+/* The gnulib override of fcntl is not needed in this file.  */
+# undef fcntl
+
+# if !HAVE_DECL_STRERROR_R
 #  ifndef HAVE_DECL_STRERROR_R
 "this configure-time declaration test was not run"
 #  endif
+#  if STRERROR_R_CHAR_P
 char *strerror_r ();
+#  else
+int strerror_r ();
+#  endif
 # endif
 
 /* The calling program should define program_name and set it to the
@@ -93,6 +123,51 @@ extern char *program_name;
 # endif	/* HAVE_STRERROR_R || defined strerror_r */
 #endif	/* not _LIBC */
 
+#if !_LIBC
+/* Return non-zero if FD is open.  */
+static int
+is_open (int fd)
+{
+# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+  /* On native Windows: The initial state of unassigned standard file
+     descriptors is that they are open but point to an INVALID_HANDLE_VALUE.
+     There is no fcntl, and the gnulib replacement fcntl does not support
+     F_GETFL.  */
+  return (HANDLE) _get_osfhandle (fd) != INVALID_HANDLE_VALUE;
+# else
+#  ifndef F_GETFL
+#   error Please port fcntl to your platform
+#  endif
+  return 0 <= fcntl (fd, F_GETFL);
+# endif
+}
+#endif
+
+static void
+flush_stdout (void)
+{
+#if !_LIBC
+  int stdout_fd;
+
+# if GNULIB_FREOPEN_SAFER
+  /* Use of gnulib's freopen-safer module normally ensures that
+       fileno (stdout) == 1
+     whenever stdout is open.  */
+  stdout_fd = STDOUT_FILENO;
+# else
+  /* POSIX states that fileno (stdout) after fclose is unspecified.  But in
+     practice it is not a problem, because stdout is statically allocated and
+     the fd of a FILE stream is stored as a field in its allocated memory.  */
+  stdout_fd = fileno (stdout);
+# endif
+  /* POSIX states that fflush (stdout) after fclose is unspecified; it
+     is safe in glibc, but not on all other platforms.  fflush (NULL)
+     is always defined, but too draconian.  */
+  if (0 <= stdout_fd && is_open (stdout_fd))
+#endif
+    fflush (stdout);
+}
+
 static void
 print_errno_message (int errnum)
 {
@@ -100,7 +175,7 @@ print_errno_message (int errnum)
 
 #if defined HAVE_STRERROR_R || _LIBC
   char errbuf[1024];
-# if STRERROR_R_CHAR_P || _LIBC
+# if _LIBC || STRERROR_R_CHAR_P
   s = __strerror_r (errnum, errbuf, sizeof errbuf);
 # else
   if (__strerror_r (errnum, errbuf, sizeof errbuf) == 0)
@@ -124,7 +199,7 @@ print_errno_message (int errnum)
 #endif
 }
 
-static void
+static void _GL_ATTRIBUTE_FORMAT_PRINTF (3, 0) _GL_ARG_NONNULL ((3))
 error_tail (int status, int errnum, const char *message, va_list args)
 {
 #if _LIBC
@@ -165,7 +240,7 @@ error_tail (int status, int errnum, const char *message, va_list args)
 	  if (res != len)
 	    break;
 
-	  if (__glibc_unlikely (len >= SIZE_MAX / sizeof (wchar_t) / 2))
+	  if (__builtin_expect (len >= SIZE_MAX / sizeof (wchar_t) / 2, 0))
 	    {
 	      /* This really should not happen if everything is fine.  */
 	      res = (size_t) -1;
@@ -227,7 +302,7 @@ error (int status, int errnum, const char *message, ...)
 		   0);
 #endif
 
-  fflush (stdout);
+  flush_stdout ();
 #ifdef _LIBC
   _IO_flockfile (stderr);
 #endif
@@ -273,6 +348,7 @@ error_at_line (int status, int errnum, const char *file_name,
 	      || (old_file_name != NULL
 		  && file_name != NULL
 		  && strcmp (old_file_name, file_name) == 0)))
+
 	/* Simply return and print nothing.  */
 	return;
 
@@ -288,7 +364,7 @@ error_at_line (int status, int errnum, const char *file_name,
 		   0);
 #endif
 
-  fflush (stdout);
+  flush_stdout ();
 #ifdef _LIBC
   _IO_flockfile (stderr);
 #endif