diff options
Diffstat (limited to 'lib/error.c')
| -rw-r--r-- | lib/error.c | 411 |
1 files changed, 411 insertions, 0 deletions
diff --git a/lib/error.c b/lib/error.c new file mode 100644 index 0000000..adc8733 --- /dev/null +++ b/lib/error.c @@ -0,0 +1,411 @@ +/* Error handler for noninteractive utilities + Copyright (C) 1990-1998, 2000-2007, 2009-2018 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. */ + +/* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */ + +#if !_LIBC +# include <config.h> +#endif + +#include "error.h" + +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#if !_LIBC && ENABLE_NLS +# include "gettext.h" +# define _(msgid) gettext (msgid) +#endif + +#ifdef _LIBC +# include <libintl.h> +# include <stdbool.h> +# include <stdint.h> +# include <wchar.h> +# define mbsrtowcs __mbsrtowcs +# define USE_UNLOCKED_IO 0 +# define _GL_ATTRIBUTE_FORMAT_PRINTF(a, b) +# define _GL_ARG_NONNULL(a) +#else +# include "getprogname.h" +#endif + +#if USE_UNLOCKED_IO +# include "unlocked-io.h" +#endif + +#ifndef _ +# define _(String) String +#endif + +/* If NULL, error will flush stdout, then print on stderr the program + name, a colon and a space. Otherwise, error will call this + function without parameters instead. */ +void (*error_print_progname) (void); + +/* This variable is incremented each time 'error' is called. */ +unsigned int error_message_count; + +#ifdef _LIBC +/* In the GNU C library, there is a predefined variable for this. */ + +# define program_name program_invocation_name +# include <errno.h> +# include <limits.h> +# include <libio/libioP.h> + +/* In GNU libc we want do not want to use the common name 'error' directly. + Instead make it a weak alias. */ +extern void __error (int status, int errnum, const char *message, ...) + __attribute__ ((__format__ (__printf__, 3, 4))); +extern void __error_at_line (int status, int errnum, const char *file_name, + unsigned int line_number, const char *message, + ...) + __attribute__ ((__format__ (__printf__, 5, 6))); +# define error __error +# define error_at_line __error_at_line + +# include <libio/iolibio.h> +# define fflush(s) _IO_fflush (s) +# undef putc +# define putc(c, fp) _IO_putc (c, fp) + +# include <bits/libc-lock.h> + +#else /* not _LIBC */ + +# include <fcntl.h> +# include <unistd.h> + +# if defined _WIN32 && ! defined __CYGWIN__ +/* Get declarations of the native Windows API functions. */ +# define WIN32_LEAN_AND_MEAN +# include <windows.h> +/* Get _get_osfhandle. */ +# if GNULIB_MSVC_NOTHROW +# include "msvc-nothrow.h" +# else +# include <io.h> +# endif +# endif + +/* The gnulib override of fcntl is not needed in this file. */ +# undef fcntl + +# if !(GNULIB_STRERROR_R_POSIX || HAVE_DECL_STRERROR_R) +# ifndef HAVE_DECL_STRERROR_R +"this configure-time declaration test was not run" +# endif +# if STRERROR_R_CHAR_P +char *strerror_r (int errnum, char *buf, size_t buflen); +# else +int strerror_r (int errnum, char *buf, size_t buflen); +# endif +# endif + +#define program_name getprogname () + +# if GNULIB_STRERROR_R_POSIX || HAVE_STRERROR_R || defined strerror_r +# define __strerror_r strerror_r +# endif /* GNULIB_STRERROR_R_POSIX || HAVE_STRERROR_R || defined strerror_r */ +#endif /* not _LIBC */ + +#if !_LIBC +/* Return non-zero if FD is open. */ +static int +is_open (int fd) +{ +# if defined _WIN32 && ! defined __CYGWIN__ + /* On native Windows: The initial state of unassigned standard file + descriptors is that they are open but point to an INVALID_HANDLE_VALUE. + There is no fcntl, and the gnulib replacement fcntl does not support + F_GETFL. */ + return (HANDLE) _get_osfhandle (fd) != INVALID_HANDLE_VALUE; +# else +# ifndef F_GETFL +# error Please port fcntl to your platform +# endif + return 0 <= fcntl (fd, F_GETFL); +# endif +} +#endif + +static void +flush_stdout (void) +{ +#if !_LIBC + int stdout_fd; + +# if GNULIB_FREOPEN_SAFER + /* Use of gnulib's freopen-safer module normally ensures that + fileno (stdout) == 1 + whenever stdout is open. */ + stdout_fd = STDOUT_FILENO; +# else + /* POSIX states that fileno (stdout) after fclose is unspecified. But in + practice it is not a problem, because stdout is statically allocated and + the fd of a FILE stream is stored as a field in its allocated memory. */ + stdout_fd = fileno (stdout); +# endif + /* POSIX states that fflush (stdout) after fclose is unspecified; it + is safe in glibc, but not on all other platforms. fflush (NULL) + is always defined, but too draconian. */ + if (0 <= stdout_fd && is_open (stdout_fd)) +#endif + fflush (stdout); +} + +static void +print_errno_message (int errnum) +{ + char const *s; + +#if _LIBC || GNULIB_STRERROR_R_POSIX || defined HAVE_STRERROR_R + char errbuf[1024]; +# if _LIBC || (!GNULIB_STRERROR_R_POSIX && STRERROR_R_CHAR_P) + s = __strerror_r (errnum, errbuf, sizeof errbuf); +# else + if (__strerror_r (errnum, errbuf, sizeof errbuf) == 0) + s = errbuf; + else + s = 0; +# endif +#else + s = strerror (errnum); +#endif + +#if !_LIBC + if (! s) + s = _("Unknown system error"); +#endif + +#if _LIBC + __fxprintf (NULL, ": %s", s); +#else + fprintf (stderr, ": %s", s); +#endif +} + +static void _GL_ATTRIBUTE_FORMAT_PRINTF (3, 0) _GL_ARG_NONNULL ((3)) +error_tail (int status, int errnum, const char *message, va_list args) +{ +#if _LIBC + if (_IO_fwide (stderr, 0) > 0) + { + size_t len = strlen (message) + 1; + wchar_t *wmessage = NULL; + mbstate_t st; + size_t res; + const char *tmp; + bool use_malloc = false; + + while (1) + { + if (__libc_use_alloca (len * sizeof (wchar_t))) + wmessage = (wchar_t *) alloca (len * sizeof (wchar_t)); + else + { + if (!use_malloc) + wmessage = NULL; + + wchar_t *p = (wchar_t *) realloc (wmessage, + len * sizeof (wchar_t)); + if (p == NULL) + { + free (wmessage); + fputws_unlocked (L"out of memory\n", stderr); + return; + } + wmessage = p; + use_malloc = true; + } + + memset (&st, '\0', sizeof (st)); + tmp = message; + + res = mbsrtowcs (wmessage, &tmp, len, &st); + if (res != len) + break; + + if (__builtin_expect (len >= SIZE_MAX / sizeof (wchar_t) / 2, 0)) + { + /* This really should not happen if everything is fine. */ + res = (size_t) -1; + break; + } + + len *= 2; + } + + if (res == (size_t) -1) + { + /* The string cannot be converted. */ + if (use_malloc) + { + free (wmessage); + use_malloc = false; + } + wmessage = (wchar_t *) L"???"; + } + + __vfwprintf (stderr, wmessage, args); + + if (use_malloc) + free (wmessage); + } + else +#endif + vfprintf (stderr, message, args); + + ++error_message_count; + if (errnum) + print_errno_message (errnum); +#if _LIBC + __fxprintf (NULL, "\n"); +#else + putc ('\n', stderr); +#endif + fflush (stderr); + if (status) + exit (status); +} + + +/* Print the program name and error message MESSAGE, which is a printf-style + format string with optional args. + If ERRNUM is nonzero, print its corresponding system error message. + Exit with status STATUS if it is nonzero. */ +void +error (int status, int errnum, const char *message, ...) +{ + va_list args; + +#if defined _LIBC && defined __libc_ptf_call + /* We do not want this call to be cut short by a thread + cancellation. Therefore disable cancellation for now. */ + int state = PTHREAD_CANCEL_ENABLE; + __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state), + 0); +#endif + + flush_stdout (); +#ifdef _LIBC + _IO_flockfile (stderr); +#endif + if (error_print_progname) + (*error_print_progname) (); + else + { +#if _LIBC + __fxprintf (NULL, "%s: ", program_name); +#else + fprintf (stderr, "%s: ", program_name); +#endif + } + + va_start (args, message); + error_tail (status, errnum, message, args); + va_end (args); + +#ifdef _LIBC + _IO_funlockfile (stderr); +# ifdef __libc_ptf_call + __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0); +# endif +#endif +} + +/* Sometimes we want to have at most one error per line. This + variable controls whether this mode is selected or not. */ +int error_one_per_line; + +void +error_at_line (int status, int errnum, const char *file_name, + unsigned int line_number, const char *message, ...) +{ + va_list args; + + if (error_one_per_line) + { + static const char *old_file_name; + static unsigned int old_line_number; + + if (old_line_number == line_number + && (file_name == old_file_name + || (old_file_name != NULL + && file_name != NULL + && strcmp (old_file_name, file_name) == 0))) + + /* Simply return and print nothing. */ + return; + + old_file_name = file_name; + old_line_number = line_number; + } + +#if defined _LIBC && defined __libc_ptf_call + /* We do not want this call to be cut short by a thread + cancellation. Therefore disable cancellation for now. */ + int state = PTHREAD_CANCEL_ENABLE; + __libc_ptf_call (pthread_setcancelstate, (PTHREAD_CANCEL_DISABLE, &state), + 0); +#endif + + flush_stdout (); +#ifdef _LIBC + _IO_flockfile (stderr); +#endif + if (error_print_progname) + (*error_print_progname) (); + else + { +#if _LIBC + __fxprintf (NULL, "%s:", program_name); +#else + fprintf (stderr, "%s:", program_name); +#endif + } + +#if _LIBC + __fxprintf (NULL, file_name != NULL ? "%s:%u: " : " ", + file_name, line_number); +#else + fprintf (stderr, file_name != NULL ? "%s:%u: " : " ", + file_name, line_number); +#endif + + va_start (args, message); + error_tail (status, errnum, message, args); + va_end (args); + +#ifdef _LIBC + _IO_funlockfile (stderr); +# ifdef __libc_ptf_call + __libc_ptf_call (pthread_setcancelstate, (state, NULL), 0); +# endif +#endif +} + +#ifdef _LIBC +/* Make the weak alias. */ +# undef error +# undef error_at_line +weak_alias (__error, error) +weak_alias (__error_at_line, error_at_line) +#endif |