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/* Copyright (C) 1993-1995,1997,2000,2002-2005,2009
Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <atomic.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysdep.h>
#include <unistd.h>
#include <sys/syslog.h>
#include <execinfo.h>
/* Abort with an error message. */
#include <not-cancel.h>
#ifdef FATAL_PREPARE_INCLUDE
#include FATAL_PREPARE_INCLUDE
#endif
struct str_list
{
const char *str;
size_t len;
struct str_list *next;
};
/* Abort with an error message. */
void
__libc_message (int do_abort, const char *fmt, ...)
{
va_list ap;
va_list ap_copy;
int fd = -1;
va_start (ap, fmt);
va_copy (ap_copy, ap);
#ifdef FATAL_PREPARE
FATAL_PREPARE;
#endif
/* Open a descriptor for /dev/tty unless the user explicitly
requests errors on standard error. */
const char *on_2 = __secure_getenv ("LIBC_FATAL_STDERR_");
if (on_2 == NULL || *on_2 == '\0')
fd = open_not_cancel_2 (_PATH_TTY, O_RDWR | O_NOCTTY | O_NDELAY);
if (fd == -1)
fd = STDERR_FILENO;
struct str_list *list = NULL;
int nlist = 0;
const char *cp = fmt;
while (*cp != '\0')
{
/* Find the next "%s" or the end of the string. */
const char *next = cp;
while (next[0] != '%' || next[1] != 's')
{
next = __strchrnul (next + 1, '%');
if (next[0] == '\0')
break;
}
/* Determine what to print. */
const char *str;
size_t len;
if (cp[0] == '%' && cp[1] == 's')
{
str = va_arg (ap, const char *);
len = strlen (str);
cp += 2;
}
else
{
str = cp;
len = next - cp;
cp = next;
}
struct str_list *newp = alloca (sizeof (struct str_list));
newp->str = str;
newp->len = len;
newp->next = list;
list = newp;
++nlist;
}
bool written = false;
if (nlist > 0)
{
struct iovec *iov = alloca (nlist * sizeof (struct iovec));
ssize_t total = 0;
for (int cnt = nlist - 1; cnt >= 0; --cnt)
{
iov[cnt].iov_base = (void *) list->str;
iov[cnt].iov_len = list->len;
total += list->len;
list = list->next;
}
INTERNAL_SYSCALL_DECL (err);
ssize_t cnt;
do
cnt = INTERNAL_SYSCALL (writev, err, 3, fd, iov, nlist);
while (INTERNAL_SYSCALL_ERROR_P (cnt, err)
&& INTERNAL_SYSCALL_ERRNO (cnt, err) == EINTR);
if (cnt == total)
written = true;
char *buf = do_abort ? malloc (total + 1) : NULL;
if (buf != NULL)
{
char *wp = buf;
for (int cnt = 0; cnt < nlist; ++cnt)
wp = mempcpy (wp, iov[cnt].iov_base, iov[cnt].iov_len);
*wp = '\0';
/* We have to free the old buffer since the application might
catch the SIGABRT signal. */
char *old = atomic_exchange_acq (&__abort_msg, buf);
free (old);
}
}
va_end (ap);
/* If we had no success writing the message, use syslog. */
if (! written)
vsyslog (LOG_ERR, fmt, ap_copy);
va_end (ap_copy);
if (do_abort)
{
if (do_abort > 1 && written)
{
void *addrs[64];
#define naddrs (sizeof (addrs) / sizeof (addrs[0]))
int n = __backtrace (addrs, naddrs);
if (n > 2)
{
#define strnsize(str) str, strlen (str)
#define writestr(str) write_not_cancel (fd, str)
writestr (strnsize ("======= Backtrace: =========\n"));
__backtrace_symbols_fd (addrs + 1, n - 1, fd);
writestr (strnsize ("======= Memory map: ========\n"));
int fd2 = open_not_cancel_2 ("/proc/self/maps", O_RDONLY);
char buf[1024];
ssize_t n2;
while ((n2 = read_not_cancel (fd2, buf, sizeof (buf))) > 0)
if (write_not_cancel (fd, buf, n2) != n2)
break;
close_not_cancel_no_status (fd2);
}
}
/* Terminate the process. */
abort ();
}
}
void
__libc_fatal (message)
const char *message;
{
/* The loop is added only to keep gcc happy. */
while (1)
__libc_message (1, "%s", message);
}
libc_hidden_def (__libc_fatal)
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