xref: /freebsd/contrib/diff/lib/error.c (revision 72d849c76142f00c8016fa1ba9d3e6c3eb5481c4)
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