1/* Error handler for noninteractive utilities 2 Copyright (C) 1990-1998, 2000-2007, 2009-2011 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# include <unistd.h> 90 91# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__ 92/* Get declarations of the Win32 API functions. */ 93# define WIN32_LEAN_AND_MEAN 94# include <windows.h> 95# endif 96 97/* The gnulib override of fcntl is not needed in this file. */ 98# undef fcntl 99 100# if !HAVE_DECL_STRERROR_R 101# ifndef HAVE_DECL_STRERROR_R 102"this configure-time declaration test was not run" 103# endif 104# if STRERROR_R_CHAR_P 105char *strerror_r (); 106# else 107int strerror_r (); 108# endif 109# endif 110 111/* The calling program should define program_name and set it to the 112 name of the executing program. */ 113extern char *program_name; 114 115# if HAVE_STRERROR_R || defined strerror_r 116# define __strerror_r strerror_r 117# endif /* HAVE_STRERROR_R || defined strerror_r */ 118#endif /* not _LIBC */ 119 120#if !_LIBC 121/* Return non-zero if FD is open. */ 122static inline int 123is_open (int fd) 124{ 125# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__ 126 /* On Win32: The initial state of unassigned standard file descriptors is 127 that they are open but point to an INVALID_HANDLE_VALUE. There is no 128 fcntl, and the gnulib replacement fcntl does not support F_GETFL. */ 129 return (HANDLE) _get_osfhandle (fd) != INVALID_HANDLE_VALUE; 130# else 131# ifndef F_GETFL 132# error Please port fcntl to your platform 133# endif 134 return 0 <= fcntl (fd, F_GETFL); 135# endif 136} 137#endif 138 139static inline void 140flush_stdout (void) 141{ 142#if !_LIBC 143 int stdout_fd; 144 145# if GNULIB_FREOPEN_SAFER 146 /* Use of gnulib's freopen-safer module normally ensures that 147 fileno (stdout) == 1 148 whenever stdout is open. */ 149 stdout_fd = STDOUT_FILENO; 150# else 151 /* POSIX states that fileno (stdout) after fclose is unspecified. But in 152 practice it is not a problem, because stdout is statically allocated and 153 the fd of a FILE stream is stored as a field in its allocated memory. */ 154 stdout_fd = fileno (stdout); 155# endif 156 /* POSIX states that fflush (stdout) after fclose is unspecified; it 157 is safe in glibc, but not on all other platforms. fflush (NULL) 158 is always defined, but too draconian. */ 159 if (0 <= stdout_fd && is_open (stdout_fd)) 160#endif 161 fflush (stdout); 162} 163 164static void 165print_errno_message (int errnum) 166{ 167 char const *s; 168 169#if defined HAVE_STRERROR_R || _LIBC 170 char errbuf[1024]; 171# if STRERROR_R_CHAR_P || _LIBC 172 s = __strerror_r (errnum, errbuf, sizeof errbuf); 173# else 174 if (__strerror_r (errnum, errbuf, sizeof errbuf) == 0) 175 s = errbuf; 176 else 177 s = 0; 178# endif 179#else 180 s = strerror (errnum); 181#endif 182 183#if !_LIBC 184 if (! s) 185 s = _("Unknown system error"); 186#endif 187 188#if _LIBC 189 __fxprintf (NULL, ": %s", s); 190#else 191 fprintf (stderr, ": %s", s); 192#endif 193} 194 195static void 196error_tail (int status, int errnum, const char *message, va_list args) 197{ 198#if _LIBC 199 if (_IO_fwide (stderr, 0) > 0) 200 { 201# define ALLOCA_LIMIT 2000 202 size_t len = strlen (message) + 1; 203 wchar_t *wmessage = NULL; 204 mbstate_t st; 205 size_t res; 206 const char *tmp; 207 bool use_malloc = false; 208 209 while (1) 210 { 211 if (__libc_use_alloca (len * sizeof (wchar_t))) 212 wmessage = (wchar_t *) alloca (len * sizeof (wchar_t)); 213 else 214 { 215 if (!use_malloc) 216 wmessage = NULL; 217 218 wchar_t *p = (wchar_t *) realloc (wmessage, 219 len * sizeof (wchar_t)); 220 if (p == NULL) 221 { 222 free (wmessage); 223 fputws_unlocked (L"out of memory\n", stderr); 224 return; 225 } 226 wmessage = p; 227 use_malloc = true; 228 } 229 230 memset (&st, '\0', sizeof (st)); 231 tmp = message; 232 233 res = mbsrtowcs (wmessage, &tmp, len, &st); 234 if (res != len) 235 break; 236 237 if (__builtin_expect (len >= SIZE_MAX / 2, 0)) 238 { 239 /* This really should not happen if everything is fine. */ 240 res = (size_t) -1; 241 break; 242 } 243 244 len *= 2; 245 } 246 247 if (res == (size_t) -1) 248 { 249 /* The string cannot be converted. */ 250 if (use_malloc) 251 { 252 free (wmessage); 253 use_malloc = false; 254 } 255 wmessage = (wchar_t *) L"???"; 256 } 257 258 __vfwprintf (stderr, wmessage, args); 259 260 if (use_malloc) 261 free (wmessage); 262 } 263 else 264#endif 265 vfprintf (stderr, message, args); 266 va_end (args); 267 268 ++error_message_count; 269 if (errnum) 270 print_errno_message (errnum); 271#if _LIBC 272 __fxprintf (NULL, "\n"); 273#else 274 putc ('\n', stderr); 275#endif 276 fflush (stderr); 277 if (status) 278 exit (status); 279} 280 281 282/* Print the program name and error message MESSAGE, which is a printf-style 283 format string with optional args. 284 If ERRNUM is nonzero, print its corresponding system error message. 285 Exit with status STATUS if it is nonzero. */ 286void 287error (int status, int errnum, const char *message, ...) 288{ 289 va_list args; 290 291#if defined _LIBC && defined __libc_ptf_call 292 /* We do not want this call to be cut short by a thread 293 cancellation. Therefore disable cancellation for now. */ 294 int state = PTHREAD_CANCEL_ENABLE; 295 __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state), 296 0); 297#endif 298 299 flush_stdout (); 300#ifdef _LIBC 301 _IO_flockfile (stderr); 302#endif 303 if (error_print_progname) 304 (*error_print_progname) (); 305 else 306 { 307#if _LIBC 308 __fxprintf (NULL, "%s: ", program_name); 309#else 310 fprintf (stderr, "%s: ", program_name); 311#endif 312 } 313 314 va_start (args, message); 315 error_tail (status, errnum, message, args); 316 317#ifdef _LIBC 318 _IO_funlockfile (stderr); 319# ifdef __libc_ptf_call 320 __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0); 321# endif 322#endif 323} 324 325/* Sometimes we want to have at most one error per line. This 326 variable controls whether this mode is selected or not. */ 327int error_one_per_line; 328 329void 330error_at_line (int status, int errnum, const char *file_name, 331 unsigned int line_number, const char *message, ...) 332{ 333 va_list args; 334 335 if (error_one_per_line) 336 { 337 static const char *old_file_name; 338 static unsigned int old_line_number; 339 340 if (old_line_number == line_number 341 && (file_name == old_file_name 342 || strcmp (old_file_name, file_name) == 0)) 343 /* Simply return and print nothing. */ 344 return; 345 346 old_file_name = file_name; 347 old_line_number = line_number; 348 } 349 350#if defined _LIBC && defined __libc_ptf_call 351 /* We do not want this call to be cut short by a thread 352 cancellation. Therefore disable cancellation for now. */ 353 int state = PTHREAD_CANCEL_ENABLE; 354 __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state), 355 0); 356#endif 357 358 flush_stdout (); 359#ifdef _LIBC 360 _IO_flockfile (stderr); 361#endif 362 if (error_print_progname) 363 (*error_print_progname) (); 364 else 365 { 366#if _LIBC 367 __fxprintf (NULL, "%s:", program_name); 368#else 369 fprintf (stderr, "%s:", program_name); 370#endif 371 } 372 373#if _LIBC 374 __fxprintf (NULL, file_name != NULL ? "%s:%d: " : " ", 375 file_name, line_number); 376#else 377 fprintf (stderr, file_name != NULL ? "%s:%d: " : " ", 378 file_name, line_number); 379#endif 380 381 va_start (args, message); 382 error_tail (status, errnum, message, args); 383 384#ifdef _LIBC 385 _IO_funlockfile (stderr); 386# ifdef __libc_ptf_call 387 __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0); 388# endif 389#endif 390} 391 392#ifdef _LIBC 393/* Make the weak alias. */ 394# undef error 395# undef error_at_line 396weak_alias (__error, error) 397weak_alias (__error_at_line, error_at_line) 398#endif 399