/* Error handler for noninteractive utilities
Copyright (C) 1990-1998, 2000-2007, 2009-2012 Free Software Foundation, Inc.
This file is part of the GNU C Library.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
#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
#endif
#if USE_UNLOCKED_IO
# include "unlocked-io.h"
#endif
#ifndef _
# define _(String) String
#endif
/* If NULL, error will flush stdout, then print on stderr the program
name, a colon and a space. Otherwise, error will call this
function without parameters instead. */
void (*error_print_progname) (void);
/* This variable is incremented each time 'error' is called. */
unsigned int error_message_count;
#ifdef _LIBC
/* In the GNU C library, there is a predefined variable for this. */
# define program_name program_invocation_name
# include <errno.h>
# include <limits.h>
# include <libio/libioP.h>
/* 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)));
extern void __error_at_line (int status, int errnum, const char *file_name,
unsigned int line_number, const char *message,
...)
__attribute__ ((__format__ (__printf__, 5, 6)));;
# define error __error
# define error_at_line __error_at_line
# include <libio/iolibio.h>
# define fflush(s) INTUSE(_IO_fflush) (s)
# undef putc
# define putc(c, fp) INTUSE(_IO_putc) (c, fp)
# include <bits/libc-lock.h>
#else /* not _LIBC */
# 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
name of the executing program. */
extern char *program_name;
# if HAVE_STRERROR_R || defined strerror_r
# define __strerror_r strerror_r
# 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)
{
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
__fxprintf (NULL, ": %s", s);
#else
fprintf (stderr, ": %s", s);
#endif
}
static void
error_tail (int status, int errnum, const char *message, va_list args)
{
#if _LIBC
if (_IO_fwide (stderr, 0) > 0)
{
# define ALLOCA_LIMIT 2000
size_t len = strlen (message) + 1;
wchar_t *wmessage = NULL;
mbstate_t st;
size_t res;
const char *tmp;
bool use_malloc = false;
while (1)
{
if (__libc_use_alloca (len * sizeof (wchar_t)))
wmessage = (wchar_t *) alloca (len * sizeof (wchar_t));
else
{
if (!use_malloc)
wmessage = NULL;
wchar_t *p = (wchar_t *) realloc (wmessage,
len * sizeof (wchar_t));
if (p == NULL)
{
free (wmessage);
fputws_unlocked (L"out of memory\n", stderr);
return;
}
wmessage = p;
use_malloc = true;
}
memset (&st, '\0', sizeof (st));
tmp = message;
res = mbsrtowcs (wmessage, &tmp, len, &st);
if (res != len)
break;
if (__builtin_expect (len >= SIZE_MAX / 2, 0))
{
/* This really should not happen if everything is fine. */
res = (size_t) -1;
break;
}
len *= 2;
}
if (res == (size_t) -1)
{
/* The string cannot be converted. */
if (use_malloc)
{
free (wmessage);
use_malloc = false;
}
wmessage = (wchar_t *) L"???";
}
__vfwprintf (stderr, wmessage, args);
if (use_malloc)
free (wmessage);
}
else
#endif
vfprintf (stderr, message, args);
va_end (args);
++error_message_count;
if (errnum)
print_errno_message (errnum);
#if _LIBC
__fxprintf (NULL, "\n");
#else
putc ('\n', stderr);
#endif
fflush (stderr);
if (status)
exit (status);
}
/* Print the program name and error message MESSAGE, which is a printf-style
format string with optional args.
If ERRNUM is nonzero, print its corresponding system error message.
Exit with status STATUS if it is nonzero. */
void
error (int status, int errnum, const char *message, ...)
{
va_list args;
#if defined _LIBC && defined __libc_ptf_call
/* We do not want this call to be cut short by a thread
cancellation. Therefore disable cancellation for now. */
int state = PTHREAD_CANCEL_ENABLE;
__libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state),
0);
#endif
flush_stdout ();
#ifdef _LIBC
_IO_flockfile (stderr);
#endif
if (error_print_progname)
(*error_print_progname) ();
else
{
#if _LIBC
__fxprintf (NULL, "%s: ", program_name);
#else
fprintf (stderr, "%s: ", program_name);
#endif
}
va_start (args, message);
error_tail (status, errnum, message, args);
#ifdef _LIBC
_IO_funlockfile (stderr);
# ifdef __libc_ptf_call
__libc_ptf_call (pthread_setcancelstate, (state, NULL), 0);
# endif
#endif
}
/* Sometimes we want to have at most one error per line. This
variable controls whether this mode is selected or not. */
int error_one_per_line;
void
error_at_line (int status, int errnum, const char *file_name,
unsigned int line_number, const char *message, ...)
{
va_list args;
if (error_one_per_line)
{
static const char *old_file_name;
static unsigned int old_line_number;
if (old_line_number == line_number
&& (file_name == old_file_name
|| strcmp (old_file_name, file_name) == 0))
/* Simply return and print nothing. */
return;
old_file_name = file_name;
old_line_number = line_number;
}
#if defined _LIBC && defined __libc_ptf_call
/* We do not want this call to be cut short by a thread
cancellation. Therefore disable cancellation for now. */
int state = PTHREAD_CANCEL_ENABLE;
__libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state),
0);
#endif
flush_stdout ();
#ifdef _LIBC
_IO_flockfile (stderr);
#endif
if (error_print_progname)
(*error_print_progname) ();
else
{
#if _LIBC
__fxprintf (NULL, "%s:", program_name);
#else
fprintf (stderr, "%s:", program_name);
#endif
}
#if _LIBC
__fxprintf (NULL, file_name != NULL ? "%s:%d: " : " ",
file_name, line_number);
#else
fprintf (stderr, file_name != NULL ? "%s:%d: " : " ",
file_name, line_number);
#endif
va_start (args, message);
error_tail (status, errnum, message, args);
#ifdef _LIBC
_IO_funlockfile (stderr);
# ifdef __libc_ptf_call
__libc_ptf_call (pthread_setcancelstate, (state, NULL), 0);
# endif
#endif
}
#ifdef _LIBC
/* Make the weak alias. */
# undef error
# undef error_at_line
weak_alias (__error, error)
weak_alias (__error_at_line, error_at_line)
#endif