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. |
4 | |
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. |
9 | |
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. |
14 | |
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/>. */ |
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 | # define USE_UNLOCKED_IO 0 |
44 | # define _GL_ATTRIBUTE_FORMAT_PRINTF(a, b) |
45 | # define _GL_ARG_NONNULL(a) |
46 | #endif |
47 | |
48 | #if USE_UNLOCKED_IO |
49 | # include "unlocked-io.h" |
50 | #endif |
51 | |
52 | #ifndef _ |
53 | # define _(String) String |
54 | #endif |
55 | |
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); |
60 | |
61 | /* This variable is incremented each time 'error' is called. */ |
62 | unsigned int error_message_count; |
63 | |
64 | #ifdef _LIBC |
65 | /* In the GNU C library, there is a predefined variable for this. */ |
66 | |
67 | # define program_name program_invocation_name |
68 | # include <errno.h> |
69 | # include <limits.h> |
70 | # include <libio/libioP.h> |
71 | |
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 |
82 | |
83 | # include <libio/iolibio.h> |
84 | # define fflush(s) _IO_fflush (s) |
85 | # undef putc |
86 | # define putc(c, fp) _IO_putc (c, fp) |
87 | |
88 | # include <libc-lock.h> |
89 | |
90 | #else /* not _LIBC */ |
91 | |
92 | # include <fcntl.h> |
93 | # include <unistd.h> |
94 | |
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 |
102 | |
103 | /* The gnulib override of fcntl is not needed in this file. */ |
104 | # undef fcntl |
105 | |
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 |
116 | |
117 | /* The calling program should define program_name and set it to the |
118 | name of the executing program. */ |
119 | extern char *program_name; |
120 | |
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 */ |
125 | |
126 | #if !_LIBC |
127 | /* Return non-zero if FD is open. */ |
128 | static int |
129 | is_open (int fd) |
130 | { |
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 |
143 | } |
144 | #endif |
145 | |
146 | static void |
147 | flush_stdout (void) |
148 | { |
149 | #if !_LIBC |
150 | int stdout_fd; |
151 | |
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); |
169 | } |
170 | |
171 | static void |
172 | print_errno_message (int errnum) |
173 | { |
174 | char const *s; |
175 | |
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 |
189 | |
190 | #if !_LIBC |
191 | if (! s) |
192 | s = _("Unknown system error" ); |
193 | #endif |
194 | |
195 | #if _LIBC |
196 | __fxprintf (NULL, ": %s" , s); |
197 | #else |
198 | fprintf (stderr, ": %s" , s); |
199 | #endif |
200 | } |
201 | |
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) |
204 | { |
205 | #if _LIBC |
206 | if (_IO_fwide (stderr, 0) > 0) |
207 | { |
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; |
214 | |
215 | while (1) |
216 | { |
217 | if (__libc_use_alloca (len * sizeof (wchar_t))) |
218 | wmessage = (wchar_t *) alloca (len * sizeof (wchar_t)); |
219 | else |
220 | { |
221 | if (!use_malloc) |
222 | wmessage = NULL; |
223 | |
224 | wchar_t *p = (wchar_t *) realloc (wmessage, |
225 | len * sizeof (wchar_t)); |
226 | if (p == NULL) |
227 | { |
228 | free (wmessage); |
229 | fputws_unlocked (L"out of memory\n" , stderr); |
230 | return; |
231 | } |
232 | wmessage = p; |
233 | use_malloc = true; |
234 | } |
235 | |
236 | memset (&st, '\0', sizeof (st)); |
237 | tmp = message; |
238 | |
239 | res = mbsrtowcs (wmessage, &tmp, len, &st); |
240 | if (res != len) |
241 | break; |
242 | |
243 | if (__builtin_expect (len >= SIZE_MAX / sizeof (wchar_t) / 2, 0)) |
244 | { |
245 | /* This really should not happen if everything is fine. */ |
246 | res = (size_t) -1; |
247 | break; |
248 | } |
249 | |
250 | len *= 2; |
251 | } |
252 | |
253 | if (res == (size_t) -1) |
254 | { |
255 | /* The string cannot be converted. */ |
256 | if (use_malloc) |
257 | { |
258 | free (wmessage); |
259 | use_malloc = false; |
260 | } |
261 | wmessage = (wchar_t *) L"???" ; |
262 | } |
263 | |
264 | __vfwprintf (stderr, wmessage, args); |
265 | |
266 | if (use_malloc) |
267 | free (wmessage); |
268 | } |
269 | else |
270 | #endif |
271 | vfprintf (stderr, message, args); |
272 | va_end (args); |
273 | |
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); |
285 | } |
286 | |
287 | |
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, ...) |
294 | { |
295 | va_list args; |
296 | |
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 |
304 | |
305 | flush_stdout (); |
306 | #ifdef _LIBC |
307 | _IO_flockfile (stderr); |
308 | #endif |
309 | if (error_print_progname) |
310 | (*error_print_progname) (); |
311 | else |
312 | { |
313 | #if _LIBC |
314 | __fxprintf (NULL, "%s: " , program_name); |
315 | #else |
316 | fprintf (stderr, "%s: " , program_name); |
317 | #endif |
318 | } |
319 | |
320 | va_start (args, message); |
321 | error_tail (status, errnum, message, args); |
322 | |
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 |
329 | } |
330 | |
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; |
334 | |
335 | void |
336 | error_at_line (int status, int errnum, const char *file_name, |
337 | unsigned int line_number, const char *message, ...) |
338 | { |
339 | va_list args; |
340 | |
341 | if (error_one_per_line) |
342 | { |
343 | static const char *old_file_name; |
344 | static unsigned int old_line_number; |
345 | |
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))) |
351 | |
352 | /* Simply return and print nothing. */ |
353 | return; |
354 | |
355 | old_file_name = file_name; |
356 | old_line_number = line_number; |
357 | } |
358 | |
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), |
365 | 0); |
366 | #endif |
367 | |
368 | flush_stdout (); |
369 | #ifdef _LIBC |
370 | _IO_flockfile (stderr); |
371 | #endif |
372 | if (error_print_progname) |
373 | (*error_print_progname) (); |
374 | else |
375 | { |
376 | #if _LIBC |
377 | __fxprintf (NULL, "%s:" , program_name); |
378 | #else |
379 | fprintf (stderr, "%s:" , program_name); |
380 | #endif |
381 | } |
382 | |
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 |
390 | |
391 | va_start (args, message); |
392 | error_tail (status, errnum, message, args); |
393 | |
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 |
400 | } |
401 | |
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 |
409 | |