view lib/xreadlink.c @ 40212:8da9577294da

unistr/*, uniconv/*: Fix undefined behaviour. Reported by Jeffrey Walton <noloader@gmail.com>. * lib/unistr/u-cpy.h (FUNC): Don't invoke memcpy with a zero size. * lib/unistr/u-cpy-alloc.h (FUNC): Likewise. * lib/uniconv/u8-conv-from-enc.c (u8_conv_from_encoding): Likewise. * lib/uniconv/u8-conv-to-enc.c (u8_conv_to_encoding): Likewise.
author Bruno Haible <bruno@clisp.org>
date Sat, 09 Mar 2019 00:01:47 +0100
parents b06060465f09
children
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/* xreadlink.c -- readlink wrapper to return the link name in malloc'd storage

   Copyright (C) 2001, 2003-2007, 2009-2019 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 <https://www.gnu.org/licenses/>.  */

/* Written by Jim Meyering <jim@meyering.net>
   and Bruno Haible <bruno@clisp.org>.  */

#include <config.h>

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

#include <errno.h>

#include "areadlink.h"
#include "xalloc.h"

/* Call readlink to get the symbolic link value of FILENAME.
   Return a pointer to that NUL-terminated string in malloc'd storage.
   If readlink fails, return NULL and set errno.
   If realloc fails, or if the link value is longer than SIZE_MAX :-),
   give a diagnostic and exit.  */

char *
xreadlink (char const *filename)
{
  char *result = areadlink (filename);
  if (result == NULL && errno == ENOMEM)
    xalloc_die ();
  return result;
}