contrib/diffutils-2.8/lib/error.c

   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 \f
 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