lib/verror.c

   1 /* va_list error handler for noninteractive utilities
   2    Copyright (C) 2006-2007, 2009-2017 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Eric Blake.  */
  18
  19 #include <config.h>
  20
  21 #include "verror.h"
  22 #include "xvasprintf.h"
  23
  24 #include <errno.h>
  25 #include <stdarg.h>
  26 #include <stdlib.h>
  27
  28 #if ENABLE_NLS
  29 # include "gettext.h"
  30 # define _(msgid) gettext (msgid)
  31 #endif
  32
  33 #ifndef _
  34 # define _(String) String
  35 #endif
  36
  37 /* Print a message with 'vfprintf (stderr, FORMAT, ARGS)';
  38    if ERRNUM is nonzero, follow it with ": " and strerror (ERRNUM).
  39    If STATUS is nonzero, terminate the program with 'exit (STATUS)'.
  40    Use the globals error_print_progname and error_message_count similarly
  41    to error().  */
  42 void
  43 verror (int status, int errnum, const char *format, va_list args)
  44 {
  45   verror_at_line (status, errnum, NULL, 0, format, args);
  46 }
  47
  48 /* Print a message with 'vfprintf (stderr, FORMAT, ARGS)';
  49    if ERRNUM is nonzero, follow it with ": " and strerror (ERRNUM).
  50    If STATUS is nonzero, terminate the program with 'exit (STATUS)'.
  51    If FNAME is not NULL, prepend the message with "FNAME:LINENO:".
  52    Use the globals error_print_progname, error_message_count, and
  53    error_one_per_line similarly to error_at_line().  */
  54 void
  55 verror_at_line (int status, int errnum, const char *file,
  56                 unsigned int line_number, const char *format, va_list args)
  57 {
  58   char *message = xvasprintf (format, args);
  59   if (message)
  60     {
  61       /* Until https://sourceware.org/bugzilla/show_bug.cgi?id=2997 is fixed,
  62          glibc violates GNU Coding Standards when the file argument to
  63          error_at_line is NULL.  */
  64       if (file)
  65         error_at_line (status, errnum, file, line_number, "%s", message);
  66       else
  67         error (status, errnum, "%s", message);
  68     }
  69   else
  70     {
  71       /* EOVERFLOW, EINVAL, and EILSEQ from xvasprintf are signs of
  72          serious programmer errors.  */
  73       error (0, errno, _("unable to display error message"));
  74       abort ();
  75     }
  76   free (message);
  77 }