view lib/strsep.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
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/* Copyright (C) 2004, 2007, 2009-2013 Free Software Foundation, Inc.

   Written by Yoann Vandoorselaere <yoann@prelude-ids.org>.

   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 2, 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/>.  */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

/* Specification.  */
#include <string.h>

char *
strsep (char **stringp, const char *delim)
{
  char *start = *stringp;
  char *ptr;

  if (start == NULL)
    return NULL;

  /* Optimize the case of no delimiters.  */
  if (delim[0] == '\0')
    {
      *stringp = NULL;
      return start;
    }

  /* Optimize the case of one delimiter.  */
  if (delim[1] == '\0')
    ptr = strchr (start, delim[0]);
  else
    /* The general case.  */
    ptr = strpbrk (start, delim);
  if (ptr == NULL)
    {
      *stringp = NULL;
      return start;
    }

  *ptr = '\0';
  *stringp = ptr + 1;

  return start;
}