1 /* Error handler for noninteractive utilities
2 Copyright (C) 1990-1998, 2000-2007 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2, or (at your option)
8 any later version.
9
10 This program 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
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License along
16 with this program; if not, write to the Free Software Foundation,
17 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
18
19 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
20
21 #if !_LIBC
22 # include <config.h>
23 #endif
24
25 #include "error.h"
26
27 #include <stdarg.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31
32 #if !_LIBC && ENABLE_NLS
33 # include "gettext.h"
34 # define _(msgid) gettext (msgid)
35 #endif
36
37 #ifdef _LIBC
38 # include <libintl.h>
39 # include <stdbool.h>
40 # include <stdint.h>
41 # include <wchar.h>
42 # define mbsrtowcs __mbsrtowcs
43 #endif
44
45 #if USE_UNLOCKED_IO
46 # include "unlocked-io.h"
47 #endif
48
49 #ifndef _
50 # define _(String) String
51 #endif
52
53 /* If NULL, error will flush stdout, then print on stderr the program
54 name, a colon and a space. Otherwise, error will call this
55 function without parameters instead. */
56 void (*error_print_progname) (void);
57
58 /* This variable is incremented each time `error' is called. */
59 unsigned int error_message_count;
60
61 #ifdef _LIBC
62 /* In the GNU C library, there is a predefined variable for this. */
63
64 # define program_name program_invocation_name
65 # include <errno.h>
66 # include <limits.h>
67 # include <libio/libioP.h>
68
69 /* In GNU libc we want do not want to use the common name `error' directly.
70 Instead make it a weak alias. */
71 extern void __error (int status, int errnum, const char *message, ...)
72 __attribute__ ((__format__ (__printf__, 3, 4)));
73 extern void __error_at_line (int status, int errnum, const char *file_name,
74 unsigned int line_number, const char *message,
75 ...)
76 __attribute__ ((__format__ (__printf__, 5, 6)));;
77 # define error __error
78 # define error_at_line __error_at_line
79
80 # include <libio/iolibio.h>
81 # define fflush(s) INTUSE(_IO_fflush) (s)
82 # undef putc
83 # define putc(c, fp) INTUSE(_IO_putc) (c, fp)
84
85 # include <bits/libc-lock.h>
86
87 #else /* not _LIBC */
88
89 # if !HAVE_DECL_STRERROR_R && STRERROR_R_CHAR_P
90 # ifndef HAVE_DECL_STRERROR_R
91 "this configure-time declaration test was not run"
92 # endif
93 char *strerror_r ();
94 # endif
95
96 /* The calling program should define program_name and set it to the
97 name of the executing program. */
98 extern char *program_name;
99
100 # if HAVE_STRERROR_R || defined strerror_r
101 # define __strerror_r strerror_r
102 # endif /* HAVE_STRERROR_R || defined strerror_r */
103 #endif /* not _LIBC */
104
105 static void
106 print_errno_message (int errnum)
107 {
108 char const *s;
109
110 #if defined HAVE_STRERROR_R || _LIBC
111 char errbuf[1024];
112 # if STRERROR_R_CHAR_P || _LIBC
113 s = __strerror_r (errnum, errbuf, sizeof errbuf);
114 # else
115 if (__strerror_r (errnum, errbuf, sizeof errbuf) == 0)
116 s = errbuf;
117 else
118 s = 0;
119 # endif
120 #else
121 s = strerror (errnum);
122 #endif
123
124 #if !_LIBC
125 if (! s)
126 s = _("Unknown system error");
127 #endif
128
129 #if _LIBC
130 __fxprintf (NULL, ": %s", s);
131 #else
132 fprintf (stderr, ": %s", s);
133 #endif
134 }
135
136 static void
137 error_tail (int status, int errnum, const char *message, va_list args)
138 {
139 #if _LIBC
140 if (_IO_fwide (stderr, 0) > 0)
141 {
142 # define ALLOCA_LIMIT 2000
143 size_t len = strlen (message) + 1;
144 wchar_t *wmessage = NULL;
145 mbstate_t st;
146 size_t res;
147 const char *tmp;
148 bool use_malloc = false;
149
150 while (1)
151 {
152 if (__libc_use_alloca (len * sizeof (wchar_t)))
153 wmessage = (wchar_t *) alloca (len * sizeof (wchar_t));
154 else
155 {
156 if (!use_malloc)
157 wmessage = NULL;
158
159 wchar_t *p = (wchar_t *) realloc (wmessage,
160 len * sizeof (wchar_t));
161 if (p == NULL)
162 {
163 free (wmessage);
164 fputws_unlocked (L"out of memory\n", stderr);
165 return;
166 }
167 wmessage = p;
168 use_malloc = true;
169 }
170
171 memset (&st, '\0', sizeof (st));
172 tmp = message;
173
174 res = mbsrtowcs (wmessage, &tmp, len, &st);
175 if (res != len)
176 break;
177
178 if (__builtin_expect (len >= SIZE_MAX / 2, 0))
179 {
180 /* This really should not happen if everything is fine. */
181 res = (size_t) -1;
182 break;
183 }
184
185 len *= 2;
186 }
187
188 if (res == (size_t) -1)
189 {
190 /* The string cannot be converted. */
191 if (use_malloc)
192 {
193 free (wmessage);
194 use_malloc = false;
195 }
196 wmessage = (wchar_t *) L"???";
197 }
198
199 __vfwprintf (stderr, wmessage, args);
200
201 if (use_malloc)
202 free (wmessage);
203 }
204 else
205 #endif
206 vfprintf (stderr, message, args);
207 va_end (args);
208
209 ++error_message_count;
210 if (errnum)
211 print_errno_message (errnum);
212 #if _LIBC
213 __fxprintf (NULL, "\n");
214 #else
215 putc ('\n', stderr);
216 #endif
217 fflush (stderr);
218 if (status)
219 exit (status);
220 }
221
222
223 /* Print the program name and error message MESSAGE, which is a printf-style
224 format string with optional args.
225 If ERRNUM is nonzero, print its corresponding system error message.
226 Exit with status STATUS if it is nonzero. */
227 void
228 error (int status, int errnum, const char *message, ...)
229 {
230 va_list args;
231
232 #if defined _LIBC && defined __libc_ptf_call
233 /* We do not want this call to be cut short by a thread
234 cancellation. Therefore disable cancellation for now. */
235 int state = PTHREAD_CANCEL_ENABLE;
236 __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state),
237 0);
238 #endif
239
240 fflush (stdout);
241 #ifdef _LIBC
242 _IO_flockfile (stderr);
243 #endif
244 if (error_print_progname)
245 (*error_print_progname) ();
246 else
247 {
248 #if _LIBC
249 __fxprintf (NULL, "%s: ", program_name);
250 #else
251 fprintf (stderr, "%s: ", program_name);
252 #endif
253 }
254
255 va_start (args, message);
256 error_tail (status, errnum, message, args);
257
258 #ifdef _LIBC
259 _IO_funlockfile (stderr);
260 # ifdef __libc_ptf_call
261 __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0);
262 # endif
263 #endif
264 }
265
266 /* Sometimes we want to have at most one error per line. This
267 variable controls whether this mode is selected or not. */
268 int error_one_per_line;
269
270 void
271 error_at_line (int status, int errnum, const char *file_name,
272 unsigned int line_number, const char *message, ...)
273 {
274 va_list args;
275
276 if (error_one_per_line)
277 {
278 static const char *old_file_name;
279 static unsigned int old_line_number;
280
281 if (old_line_number == line_number
282 && (file_name == old_file_name
283 || strcmp (old_file_name, file_name) == 0))
284 /* Simply return and print nothing. */
285 return;
286
287 old_file_name = file_name;
288 old_line_number = line_number;
289 }
290
291 #if defined _LIBC && defined __libc_ptf_call
292 /* We do not want this call to be cut short by a thread
293 cancellation. Therefore disable cancellation for now. */
294 int state = PTHREAD_CANCEL_ENABLE;
295 __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state),
296 0);
297 #endif
298
299 fflush (stdout);
300 #ifdef _LIBC
301 _IO_flockfile (stderr);
302 #endif
303 if (error_print_progname)
304 (*error_print_progname) ();
305 else
306 {
307 #if _LIBC
308 __fxprintf (NULL, "%s:", program_name);
309 #else
310 fprintf (stderr, "%s:", program_name);
311 #endif
312 }
313
314 #if _LIBC
315 __fxprintf (NULL, file_name != NULL ? "%s:%d: " : " ",
316 file_name, line_number);
317 #else
318 fprintf (stderr, file_name != NULL ? "%s:%d: " : " ",
319 file_name, line_number);
320 #endif
321
322 va_start (args, message);
323 error_tail (status, errnum, message, args);
324
325 #ifdef _LIBC
326 _IO_funlockfile (stderr);
327 # ifdef __libc_ptf_call
328 __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0);
329 # endif
330 #endif
331 }
332
333 #ifdef _LIBC
334 /* Make the weak alias. */
335 # undef error
336 # undef error_at_line
337 weak_alias (__error, error)
338 weak_alias (__error_at_line, error_at_line)
339 #endif