view lib/strnlen1.c @ 37246:5cfb3a67238d

regex: avoid glibc deadlock during configure glibc has a known bug where certain corruptions of the heap can cause malloc to default to printing a debug message that includes a backtrace, but the act of getting the backtrace uses dlopen which in turn calls into malloc, causing a recursive lock ending in deadlock. Thus, when configure is probing for a known glibc heap corruption bug, the overall configure would hang. The solution suggested by glibc developers is to force malloc to quit printing debug messages, which avoids recursive malloc. * m4/regex.m4 (gl_REGEX): Avoid recursive malloc deadlock when glibc bug 15078 in turn triggers bug 16159. Reported by Michal Privoznik. Signed-off-by: Eric Blake <eblake@redhat.com>
author Eric Blake <eblake@redhat.com>
date Tue, 03 Dec 2013 10:34:13 -0700
parents c741bc27922a
children 344018b6e5d7
line wrap: on
line source

/* Find the length of STRING + 1, but scan at most MAXLEN bytes.
   Copyright (C) 2005-2006, 2009-2013 Free Software Foundation, Inc.

   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 <http://www.gnu.org/licenses/>.  */

#include <config.h>

/* Specification.  */
#include "strnlen1.h"

#include <string.h>

/* Find the length of STRING + 1, but scan at most MAXLEN bytes.
   If no '\0' terminator is found in that many characters, return MAXLEN.  */
/* This is the same as strnlen (string, maxlen - 1) + 1.  */
size_t
strnlen1 (const char *string, size_t maxlen)
{
  const char *end = (const char *) memchr (string, '\0', maxlen);
  if (end != NULL)
    return end - string + 1;
  else
    return maxlen;
}