summary refs log tree commit diff
path: root/misc/error.c
blob: aaa120d5abd716af134cf6bea514168ae17fe34d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
/* Error handler for noninteractive utilities
   Copyright (C) 1990-2015 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; 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
# define USE_UNLOCKED_IO 0
# define _GL_ATTRIBUTE_FORMAT_PRINTF(a, b)
# define _GL_ARG_NONNULL(a)
#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) _IO_fflush (s)
# undef putc
# define putc(c, fp) _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 _LIBC || STRERROR_R_CHAR_P
  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 _GL_ATTRIBUTE_FORMAT_PRINTF (3, 0) _GL_ARG_NONNULL ((3))
error_tail (int status, int errnum, const char *message, va_list args)
{
#if _LIBC
  if (_IO_fwide (stderr, 0) > 0)
    {
      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 / sizeof (wchar_t) / 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
	      || (old_file_name != NULL
		  && file_name != NULL
		  && 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