Fix build errors with -DNDEBUG.
[glibc.git] / misc / error.c
blobc4c0ae95fda6d4f3a7ca10bf25d4b6f97645d546
1 /* Error handler for noninteractive utilities
2 Copyright (C) 1990-2016 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
19 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
21 #if !_LIBC
22 # include <config.h>
23 #endif
25 #include "error.h"
27 #include <stdarg.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
32 #if !_LIBC && ENABLE_NLS
33 # include "gettext.h"
34 # define _(msgid) gettext (msgid)
35 #endif
37 #ifdef _LIBC
38 # include <libintl.h>
39 # include <stdbool.h>
40 # include <stdint.h>
41 # include <wchar.h>
42 # define mbsrtowcs __mbsrtowcs
43 # define USE_UNLOCKED_IO 0
44 # define _GL_ATTRIBUTE_FORMAT_PRINTF(a, b)
45 # define _GL_ARG_NONNULL(a)
46 #endif
48 #if USE_UNLOCKED_IO
49 # include "unlocked-io.h"
50 #endif
52 #ifndef _
53 # define _(String) String
54 #endif
56 /* If NULL, error will flush stdout, then print on stderr the program
57 name, a colon and a space. Otherwise, error will call this
58 function without parameters instead. */
59 void (*error_print_progname) (void);
61 /* This variable is incremented each time 'error' is called. */
62 unsigned int error_message_count;
64 #ifdef _LIBC
65 /* In the GNU C library, there is a predefined variable for this. */
67 # define program_name program_invocation_name
68 # include <errno.h>
69 # include <limits.h>
70 # include <libio/libioP.h>
72 /* In GNU libc we want do not want to use the common name 'error' directly.
73 Instead make it a weak alias. */
74 extern void __error (int status, int errnum, const char *message, ...)
75 __attribute__ ((__format__ (__printf__, 3, 4)));
76 extern void __error_at_line (int status, int errnum, const char *file_name,
77 unsigned int line_number, const char *message,
78 ...)
79 __attribute__ ((__format__ (__printf__, 5, 6)));;
80 # define error __error
81 # define error_at_line __error_at_line
83 # include <libio/iolibio.h>
84 # define fflush(s) _IO_fflush (s)
85 # undef putc
86 # define putc(c, fp) _IO_putc (c, fp)
88 # include <libc-lock.h>
90 #else /* not _LIBC */
92 # include <fcntl.h>
93 # include <unistd.h>
95 # if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
96 /* Get declarations of the native Windows API functions. */
97 # define WIN32_LEAN_AND_MEAN
98 # include <windows.h>
99 /* Get _get_osfhandle. */
100 # include "msvc-nothrow.h"
101 # endif
103 /* The gnulib override of fcntl is not needed in this file. */
104 # undef fcntl
106 # if !HAVE_DECL_STRERROR_R
107 # ifndef HAVE_DECL_STRERROR_R
108 "this configure-time declaration test was not run"
109 # endif
110 # if STRERROR_R_CHAR_P
111 char *strerror_r ();
112 # else
113 int strerror_r ();
114 # endif
115 # endif
117 /* The calling program should define program_name and set it to the
118 name of the executing program. */
119 extern char *program_name;
121 # if HAVE_STRERROR_R || defined strerror_r
122 # define __strerror_r strerror_r
123 # endif /* HAVE_STRERROR_R || defined strerror_r */
124 #endif /* not _LIBC */
126 #if !_LIBC
127 /* Return non-zero if FD is open. */
128 static int
129 is_open (int fd)
131 # if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
132 /* On native Windows: The initial state of unassigned standard file
133 descriptors is that they are open but point to an INVALID_HANDLE_VALUE.
134 There is no fcntl, and the gnulib replacement fcntl does not support
135 F_GETFL. */
136 return (HANDLE) _get_osfhandle (fd) != INVALID_HANDLE_VALUE;
137 # else
138 # ifndef F_GETFL
139 # error Please port fcntl to your platform
140 # endif
141 return 0 <= fcntl (fd, F_GETFL);
142 # endif
144 #endif
146 static void
147 flush_stdout (void)
149 #if !_LIBC
150 int stdout_fd;
152 # if GNULIB_FREOPEN_SAFER
153 /* Use of gnulib's freopen-safer module normally ensures that
154 fileno (stdout) == 1
155 whenever stdout is open. */
156 stdout_fd = STDOUT_FILENO;
157 # else
158 /* POSIX states that fileno (stdout) after fclose is unspecified. But in
159 practice it is not a problem, because stdout is statically allocated and
160 the fd of a FILE stream is stored as a field in its allocated memory. */
161 stdout_fd = fileno (stdout);
162 # endif
163 /* POSIX states that fflush (stdout) after fclose is unspecified; it
164 is safe in glibc, but not on all other platforms. fflush (NULL)
165 is always defined, but too draconian. */
166 if (0 <= stdout_fd && is_open (stdout_fd))
167 #endif
168 fflush (stdout);
171 static void
172 print_errno_message (int errnum)
174 char const *s;
176 #if defined HAVE_STRERROR_R || _LIBC
177 char errbuf[1024];
178 # if _LIBC || STRERROR_R_CHAR_P
179 s = __strerror_r (errnum, errbuf, sizeof errbuf);
180 # else
181 if (__strerror_r (errnum, errbuf, sizeof errbuf) == 0)
182 s = errbuf;
183 else
184 s = 0;
185 # endif
186 #else
187 s = strerror (errnum);
188 #endif
190 #if !_LIBC
191 if (! s)
192 s = _("Unknown system error");
193 #endif
195 #if _LIBC
196 __fxprintf (NULL, ": %s", s);
197 #else
198 fprintf (stderr, ": %s", s);
199 #endif
202 static void _GL_ATTRIBUTE_FORMAT_PRINTF (3, 0) _GL_ARG_NONNULL ((3))
203 error_tail (int status, int errnum, const char *message, va_list args)
205 #if _LIBC
206 if (_IO_fwide (stderr, 0) > 0)
208 size_t len = strlen (message) + 1;
209 wchar_t *wmessage = NULL;
210 mbstate_t st;
211 size_t res;
212 const char *tmp;
213 bool use_malloc = false;
215 while (1)
217 if (__libc_use_alloca (len * sizeof (wchar_t)))
218 wmessage = (wchar_t *) alloca (len * sizeof (wchar_t));
219 else
221 if (!use_malloc)
222 wmessage = NULL;
224 wchar_t *p = (wchar_t *) realloc (wmessage,
225 len * sizeof (wchar_t));
226 if (p == NULL)
228 free (wmessage);
229 fputws_unlocked (L"out of memory\n", stderr);
230 return;
232 wmessage = p;
233 use_malloc = true;
236 memset (&st, '\0', sizeof (st));
237 tmp = message;
239 res = mbsrtowcs (wmessage, &tmp, len, &st);
240 if (res != len)
241 break;
243 if (__builtin_expect (len >= SIZE_MAX / sizeof (wchar_t) / 2, 0))
245 /* This really should not happen if everything is fine. */
246 res = (size_t) -1;
247 break;
250 len *= 2;
253 if (res == (size_t) -1)
255 /* The string cannot be converted. */
256 if (use_malloc)
258 free (wmessage);
259 use_malloc = false;
261 wmessage = (wchar_t *) L"???";
264 __vfwprintf (stderr, wmessage, args);
266 if (use_malloc)
267 free (wmessage);
269 else
270 #endif
271 vfprintf (stderr, message, args);
272 va_end (args);
274 ++error_message_count;
275 if (errnum)
276 print_errno_message (errnum);
277 #if _LIBC
278 __fxprintf (NULL, "\n");
279 #else
280 putc ('\n', stderr);
281 #endif
282 fflush (stderr);
283 if (status)
284 exit (status);
288 /* Print the program name and error message MESSAGE, which is a printf-style
289 format string with optional args.
290 If ERRNUM is nonzero, print its corresponding system error message.
291 Exit with status STATUS if it is nonzero. */
292 void
293 error (int status, int errnum, const char *message, ...)
295 va_list args;
297 #if defined _LIBC && defined __libc_ptf_call
298 /* We do not want this call to be cut short by a thread
299 cancellation. Therefore disable cancellation for now. */
300 int state = PTHREAD_CANCEL_ENABLE;
301 __libc_ptf_call (__pthread_setcancelstate,
302 (PTHREAD_CANCEL_DISABLE, &state), 0);
303 #endif
305 flush_stdout ();
306 #ifdef _LIBC
307 _IO_flockfile (stderr);
308 #endif
309 if (error_print_progname)
310 (*error_print_progname) ();
311 else
313 #if _LIBC
314 __fxprintf (NULL, "%s: ", program_name);
315 #else
316 fprintf (stderr, "%s: ", program_name);
317 #endif
320 va_start (args, message);
321 error_tail (status, errnum, message, args);
323 #ifdef _LIBC
324 _IO_funlockfile (stderr);
325 # ifdef __libc_ptf_call
326 __libc_ptf_call (__pthread_setcancelstate, (state, NULL), 0);
327 # endif
328 #endif
331 /* Sometimes we want to have at most one error per line. This
332 variable controls whether this mode is selected or not. */
333 int error_one_per_line;
335 void
336 error_at_line (int status, int errnum, const char *file_name,
337 unsigned int line_number, const char *message, ...)
339 va_list args;
341 if (error_one_per_line)
343 static const char *old_file_name;
344 static unsigned int old_line_number;
346 if (old_line_number == line_number
347 && (file_name == old_file_name
348 || (old_file_name != NULL
349 && file_name != NULL
350 && strcmp (old_file_name, file_name) == 0)))
352 /* Simply return and print nothing. */
353 return;
355 old_file_name = file_name;
356 old_line_number = line_number;
359 #if defined _LIBC && defined __libc_ptf_call
360 /* We do not want this call to be cut short by a thread
361 cancellation. Therefore disable cancellation for now. */
362 int state = PTHREAD_CANCEL_ENABLE;
363 __libc_ptf_call (__pthread_setcancelstate,
364 (PTHREAD_CANCEL_DISABLE, &state),
366 #endif
368 flush_stdout ();
369 #ifdef _LIBC
370 _IO_flockfile (stderr);
371 #endif
372 if (error_print_progname)
373 (*error_print_progname) ();
374 else
376 #if _LIBC
377 __fxprintf (NULL, "%s:", program_name);
378 #else
379 fprintf (stderr, "%s:", program_name);
380 #endif
383 #if _LIBC
384 __fxprintf (NULL, file_name != NULL ? "%s:%d: " : " ",
385 file_name, line_number);
386 #else
387 fprintf (stderr, file_name != NULL ? "%s:%d: " : " ",
388 file_name, line_number);
389 #endif
391 va_start (args, message);
392 error_tail (status, errnum, message, args);
394 #ifdef _LIBC
395 _IO_funlockfile (stderr);
396 # ifdef __libc_ptf_call
397 __libc_ptf_call (__pthread_setcancelstate, (state, NULL), 0);
398 # endif
399 #endif
402 #ifdef _LIBC
403 /* Make the weak alias. */
404 # undef error
405 # undef error_at_line
406 weak_alias (__error, error)
407 weak_alias (__error_at_line, error_at_line)
408 #endif