1/* Error handler for noninteractive utilities 2 Copyright (C) 1990-1998, 2000-2007, 2009 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 3 of the License, or 8 (at your option) 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 16 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 17 18/* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */ 19 20#if !_LIBC 21# include <config.h> 22#endif 23 24#include "error.h" 25 26#include <stdarg.h> 27#include <stdio.h> 28#include <stdlib.h> 29#include <string.h> 30 31#if !_LIBC && ENABLE_NLS 32# include "gettext.h" 33# define _(msgid) gettext (msgid) 34#endif 35 36#ifdef _LIBC 37# include <libintl.h> 38# include <stdbool.h> 39# include <stdint.h> 40# include <wchar.h> 41# define mbsrtowcs __mbsrtowcs 42#endif 43 44#if USE_UNLOCKED_IO 45# include "unlocked-io.h" 46#endif 47 48#ifndef _ 49# define _(String) String 50#endif 51 52/* If NULL, error will flush stdout, then print on stderr the program 53 name, a colon and a space. Otherwise, error will call this 54 function without parameters instead. */ 55void (*error_print_progname) (void); 56 57/* This variable is incremented each time `error' is called. */ 58unsigned int error_message_count; 59 60#ifdef _LIBC 61/* In the GNU C library, there is a predefined variable for this. */ 62 63# define program_name program_invocation_name 64# include <errno.h> 65# include <limits.h> 66# include <libio/libioP.h> 67 68/* In GNU libc we want do not want to use the common name `error' directly. 69 Instead make it a weak alias. */ 70extern void __error (int status, int errnum, const char *message, ...) 71 __attribute__ ((__format__ (__printf__, 3, 4))); 72extern void __error_at_line (int status, int errnum, const char *file_name, 73 unsigned int line_number, const char *message, 74 ...) 75 __attribute__ ((__format__ (__printf__, 5, 6)));; 76# define error __error 77# define error_at_line __error_at_line 78 79# include <libio/iolibio.h> 80# define fflush(s) INTUSE(_IO_fflush) (s) 81# undef putc 82# define putc(c, fp) INTUSE(_IO_putc) (c, fp) 83 84# include <bits/libc-lock.h> 85 86#else /* not _LIBC */ 87 88# include <fcntl.h> 89 90# if !HAVE_DECL_STRERROR_R && STRERROR_R_CHAR_P 91# ifndef HAVE_DECL_STRERROR_R 92"this configure-time declaration test was not run" 93# endif 94char *strerror_r (); 95# endif 96 97/* The calling program should define program_name and set it to the 98 name of the executing program. */ 99extern char *program_name; 100 101# if HAVE_STRERROR_R || defined strerror_r 102# define __strerror_r strerror_r 103# endif /* HAVE_STRERROR_R || defined strerror_r */ 104#endif /* not _LIBC */ 105 106static void 107print_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 __fxprintf (NULL, ": %s", s); 132#else 133 fprintf (stderr, ": %s", s); 134#endif 135} 136 137static void 138error_tail (int status, int errnum, const char *message, va_list args) 139{ 140#if _LIBC 141 if (_IO_fwide (stderr, 0) > 0) 142 { 143# define ALLOCA_LIMIT 2000 144 size_t len = strlen (message) + 1; 145 wchar_t *wmessage = NULL; 146 mbstate_t st; 147 size_t res; 148 const char *tmp; 149 bool use_malloc = false; 150 151 while (1) 152 { 153 if (__libc_use_alloca (len * sizeof (wchar_t))) 154 wmessage = (wchar_t *) alloca (len * sizeof (wchar_t)); 155 else 156 { 157 if (!use_malloc) 158 wmessage = NULL; 159 160 wchar_t *p = (wchar_t *) realloc (wmessage, 161 len * sizeof (wchar_t)); 162 if (p == NULL) 163 { 164 free (wmessage); 165 fputws_unlocked (L"out of memory\n", stderr); 166 return; 167 } 168 wmessage = p; 169 use_malloc = true; 170 } 171 172 memset (&st, '\0', sizeof (st)); 173 tmp = message; 174 175 res = mbsrtowcs (wmessage, &tmp, len, &st); 176 if (res != len) 177 break; 178 179 if (__builtin_expect (len >= SIZE_MAX / 2, 0)) 180 { 181 /* This really should not happen if everything is fine. */ 182 res = (size_t) -1; 183 break; 184 } 185 186 len *= 2; 187 } 188 189 if (res == (size_t) -1) 190 { 191 /* The string cannot be converted. */ 192 if (use_malloc) 193 { 194 free (wmessage); 195 use_malloc = false; 196 } 197 wmessage = (wchar_t *) L"???"; 198 } 199 200 __vfwprintf (stderr, wmessage, args); 201 202 if (use_malloc) 203 free (wmessage); 204 } 205 else 206#endif 207 vfprintf (stderr, message, args); 208 va_end (args); 209 210 ++error_message_count; 211 if (errnum) 212 print_errno_message (errnum); 213#if _LIBC 214 __fxprintf (NULL, "\n"); 215#else 216 putc ('\n', stderr); 217#endif 218 fflush (stderr); 219 if (status) 220 exit (status); 221} 222 223 224/* Print the program name and error message MESSAGE, which is a printf-style 225 format string with optional args. 226 If ERRNUM is nonzero, print its corresponding system error message. 227 Exit with status STATUS if it is nonzero. */ 228void 229error (int status, int errnum, const char *message, ...) 230{ 231 va_list args; 232 233#if defined _LIBC && defined __libc_ptf_call 234 /* We do not want this call to be cut short by a thread 235 cancellation. Therefore disable cancellation for now. */ 236 int state = PTHREAD_CANCEL_ENABLE; 237 __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state), 238 0); 239#endif 240 241#if !_LIBC && defined F_GETFL 242 /* POSIX states that fflush (stdout) after fclose is unspecified; it 243 is safe in glibc, but not on all other platforms. fflush (NULL) 244 is always defined, but too draconian. */ 245 if (0 <= fcntl (1, F_GETFL)) 246#endif 247 fflush (stdout); 248#ifdef _LIBC 249 _IO_flockfile (stderr); 250#endif 251 if (error_print_progname) 252 (*error_print_progname) (); 253 else 254 { 255#if _LIBC 256 __fxprintf (NULL, "%s: ", program_name); 257#else 258 fprintf (stderr, "%s: ", program_name); 259#endif 260 } 261 262 va_start (args, message); 263 error_tail (status, errnum, message, args); 264 265#ifdef _LIBC 266 _IO_funlockfile (stderr); 267# ifdef __libc_ptf_call 268 __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0); 269# endif 270#endif 271} 272 273/* Sometimes we want to have at most one error per line. This 274 variable controls whether this mode is selected or not. */ 275int error_one_per_line; 276 277void 278error_at_line (int status, int errnum, const char *file_name, 279 unsigned int line_number, const char *message, ...) 280{ 281 va_list args; 282 283 if (error_one_per_line) 284 { 285 static const char *old_file_name; 286 static unsigned int old_line_number; 287 288 if (old_line_number == line_number 289 && (file_name == old_file_name 290 || strcmp (old_file_name, file_name) == 0)) 291 /* Simply return and print nothing. */ 292 return; 293 294 old_file_name = file_name; 295 old_line_number = line_number; 296 } 297 298#if defined _LIBC && defined __libc_ptf_call 299 /* We do not want this call to be cut short by a thread 300 cancellation. Therefore disable cancellation for now. */ 301 int state = PTHREAD_CANCEL_ENABLE; 302 __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state), 303 0); 304#endif 305 306#if !_LIBC && defined F_GETFL 307 /* POSIX states that fflush (stdout) after fclose is unspecified; it 308 is safe in glibc, but not on all other platforms. fflush (NULL) 309 is always defined, but too draconian. */ 310 if (0 <= fcntl (1, F_GETFL)) 311#endif 312 fflush (stdout); 313#ifdef _LIBC 314 _IO_flockfile (stderr); 315#endif 316 if (error_print_progname) 317 (*error_print_progname) (); 318 else 319 { 320#if _LIBC 321 __fxprintf (NULL, "%s:", program_name); 322#else 323 fprintf (stderr, "%s:", program_name); 324#endif 325 } 326 327#if _LIBC 328 __fxprintf (NULL, file_name != NULL ? "%s:%d: " : " ", 329 file_name, line_number); 330#else 331 fprintf (stderr, file_name != NULL ? "%s:%d: " : " ", 332 file_name, line_number); 333#endif 334 335 va_start (args, message); 336 error_tail (status, errnum, message, args); 337 338#ifdef _LIBC 339 _IO_funlockfile (stderr); 340# ifdef __libc_ptf_call 341 __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0); 342# endif 343#endif 344} 345 346#ifdef _LIBC 347/* Make the weak alias. */ 348# undef error 349# undef error_at_line 350weak_alias (__error, error) 351weak_alias (__error_at_line, error_at_line) 352#endif 353