xref: /freebsd/contrib/diff/lib/error.c (revision 123af6ec70016f5556da5972d4d63c7d175c06d3)
1 /* Error handler for noninteractive utilities
2    Copyright (C) 1990-1998, 2000-2002, 2003 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
18 
19 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>.  */
20 
21 #ifdef HAVE_CONFIG_H
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 #ifdef _LIBC
33 # include <libintl.h>
34 #else
35 # include "gettext.h"
36 #endif
37 
38 #ifdef _LIBC
39 # include <wchar.h>
40 # define mbsrtowcs __mbsrtowcs
41 #endif
42 
43 #if !_LIBC
44 # include "unlocked-io.h"
45 #endif
46 
47 #ifndef _
48 # define _(String) String
49 #endif
50 
51 /* If NULL, error will flush stdout, then print on stderr the program
52    name, a colon and a space.  Otherwise, error will call this
53    function without parameters instead.  */
54 void (*error_print_progname) (void);
55 
56 /* This variable is incremented each time `error' is called.  */
57 unsigned int error_message_count;
58 
59 #ifdef _LIBC
60 /* In the GNU C library, there is a predefined variable for this.  */
61 
62 # define program_name program_invocation_name
63 # include <errno.h>
64 # include <libio/libioP.h>
65 
66 /* In GNU libc we want do not want to use the common name `error' directly.
67    Instead make it a weak alias.  */
68 extern void __error (int status, int errnum, const char *message, ...)
69      __attribute__ ((__format__ (__printf__, 3, 4)));
70 extern void __error_at_line (int status, int errnum, const char *file_name,
71 			     unsigned int line_number, const char *message,
72 			     ...)
73      __attribute__ ((__format__ (__printf__, 5, 6)));;
74 # define error __error
75 # define error_at_line __error_at_line
76 
77 # include <libio/iolibio.h>
78 # define fflush(s) INTUSE(_IO_fflush) (s)
79 # undef putc
80 # define putc(c, fp) INTUSE(_IO_putc) (c, fp)
81 
82 # include <bits/libc-lock.h>
83 
84 #else /* not _LIBC */
85 
86 # if !HAVE_DECL_STRERROR_R && STRERROR_R_CHAR_P
87 #  ifndef HAVE_DECL_STRERROR_R
88 "this configure-time declaration test was not run"
89 #  endif
90 char *strerror_r ();
91 # endif
92 
93 # ifndef SIZE_MAX
94 #  define SIZE_MAX ((size_t) -1)
95 # endif
96 
97 /* The calling program should define program_name and set it to the
98    name of the executing program.  */
99 extern char *program_name;
100 
101 # if HAVE_STRERROR_R || defined strerror_r
102 #  define __strerror_r strerror_r
103 # endif
104 #endif	/* not _LIBC */
105 
106 static void
107 print_errno_message (int errnum)
108 {
109   char const *s;
110 
111 #if defined HAVE_STRERROR_R || _LIBC
112   char errbuf[1024];
113 # if STRERROR_R_CHAR_P || _LIBC
114   s = __strerror_r (errnum, errbuf, sizeof errbuf);
115 # else
116   if (__strerror_r (errnum, errbuf, sizeof errbuf) == 0)
117     s = errbuf;
118   else
119     s = 0;
120 # endif
121 #else
122   s = strerror (errnum);
123 #endif
124 
125 #if !_LIBC
126   if (! s)
127     s = _("Unknown system error");
128 #endif
129 
130 #if _LIBC
131   if (_IO_fwide (stderr, 0) > 0)
132     {
133       __fwprintf (stderr, L": %s", s);
134       return;
135     }
136 #endif
137 
138   fprintf (stderr, ": %s", s);
139 }
140 
141 static void
142 error_tail (int status, int errnum, const char *message, va_list args)
143 {
144 #if _LIBC
145   if (_IO_fwide (stderr, 0) > 0)
146     {
147 # define ALLOCA_LIMIT 2000
148       size_t len = strlen (message) + 1;
149       const wchar_t *wmessage = L"out of memory";
150       wchar_t *wbuf = (len < ALLOCA_LIMIT
151 		       ? alloca (len * sizeof *wbuf)
152 		       : len <= SIZE_MAX / sizeof *wbuf
153 		       ? malloc (len * sizeof *wbuf)
154 		       : NULL);
155 
156       if (wbuf)
157 	{
158 	  size_t res;
159 	  mbstate_t st;
160 	  const char *tmp = message;
161 	  memset (&st, '\0', sizeof (st));
162 	  res = mbsrtowcs (wbuf, &tmp, len, &st);
163 	  wmessage = res == (size_t) -1 ? L"???" : wbuf;
164 	}
165 
166       __vfwprintf (stderr, wmessage, args);
167       if (! (len < ALLOCA_LIMIT))
168 	free (wbuf);
169     }
170   else
171 #endif
172     vfprintf (stderr, message, args);
173   va_end (args);
174 
175   ++error_message_count;
176   if (errnum)
177     print_errno_message (errnum);
178 #if _LIBC
179   if (_IO_fwide (stderr, 0) > 0)
180     putwc (L'\n', stderr);
181   else
182 #endif
183     putc ('\n', stderr);
184   fflush (stderr);
185   if (status)
186     exit (status);
187 }
188 
189 
190 /* Print the program name and error message MESSAGE, which is a printf-style
191    format string with optional args.
192    If ERRNUM is nonzero, print its corresponding system error message.
193    Exit with status STATUS if it is nonzero.  */
194 void
195 error (int status, int errnum, const char *message, ...)
196 {
197   va_list args;
198 
199 #if defined _LIBC && defined __libc_ptf_call
200   /* We do not want this call to be cut short by a thread
201      cancellation.  Therefore disable cancellation for now.  */
202   int state = PTHREAD_CANCEL_ENABLE;
203   __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state),
204 		   0);
205 #endif
206 
207   fflush (stdout);
208 #ifdef _LIBC
209   _IO_flockfile (stderr);
210 #endif
211   if (error_print_progname)
212     (*error_print_progname) ();
213   else
214     {
215 #if _LIBC
216       if (_IO_fwide (stderr, 0) > 0)
217 	__fwprintf (stderr, L"%s: ", program_name);
218       else
219 #endif
220 	fprintf (stderr, "%s: ", program_name);
221     }
222 
223   va_start (args, message);
224   error_tail (status, errnum, message, args);
225 
226 #ifdef _LIBC
227   _IO_funlockfile (stderr);
228 # ifdef __libc_ptf_call
229   __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0);
230 # endif
231 #endif
232 }
233 
234 /* Sometimes we want to have at most one error per line.  This
235    variable controls whether this mode is selected or not.  */
236 int error_one_per_line;
237 
238 void
239 error_at_line (int status, int errnum, const char *file_name,
240 	       unsigned int line_number, const char *message, ...)
241 {
242   va_list args;
243 
244   if (error_one_per_line)
245     {
246       static const char *old_file_name;
247       static unsigned int old_line_number;
248 
249       if (old_line_number == line_number
250 	  && (file_name == old_file_name
251 	      || strcmp (old_file_name, file_name) == 0))
252 	/* Simply return and print nothing.  */
253 	return;
254 
255       old_file_name = file_name;
256       old_line_number = line_number;
257     }
258 
259 #if defined _LIBC && defined __libc_ptf_call
260   /* We do not want this call to be cut short by a thread
261      cancellation.  Therefore disable cancellation for now.  */
262   int state = PTHREAD_CANCEL_ENABLE;
263   __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state),
264 		   0);
265 #endif
266 
267   fflush (stdout);
268 #ifdef _LIBC
269   _IO_flockfile (stderr);
270 #endif
271   if (error_print_progname)
272     (*error_print_progname) ();
273   else
274     {
275 #if _LIBC
276       if (_IO_fwide (stderr, 0) > 0)
277 	__fwprintf (stderr, L"%s: ", program_name);
278       else
279 #endif
280 	fprintf (stderr, "%s:", program_name);
281     }
282 
283   if (file_name != NULL)
284     {
285 #if _LIBC
286       if (_IO_fwide (stderr, 0) > 0)
287 	__fwprintf (stderr, L"%s:%d: ", file_name, line_number);
288       else
289 #endif
290 	fprintf (stderr, "%s:%d: ", file_name, line_number);
291     }
292 
293   va_start (args, message);
294   error_tail (status, errnum, message, args);
295 
296 #ifdef _LIBC
297   _IO_funlockfile (stderr);
298 # ifdef __libc_ptf_call
299   __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0);
300 # endif
301 #endif
302 }
303 
304 #ifdef _LIBC
305 /* Make the weak alias.  */
306 # undef error
307 # undef error_at_line
308 weak_alias (__error, error)
309 weak_alias (__error_at_line, error_at_line)
310 #endif
311