X-Git-Url: https://git.cworth.org/git?p=tar;a=blobdiff_plain;f=gnu%2Fareadlink-with-size.c;fp=gnu%2Fareadlink-with-size.c;h=0000000000000000000000000000000000000000;hp=8370184cd533b8c3512b5f11ee7c9c1e6a6def78;hb=b414e25de8ca49d7567a92c203d431383ec57c83;hpb=29ece34f44a27750bbfd76154ad9882580453dc7 diff --git a/gnu/areadlink-with-size.c b/gnu/areadlink-with-size.c deleted file mode 100644 index 8370184..0000000 --- a/gnu/areadlink-with-size.c +++ /dev/null @@ -1,106 +0,0 @@ -/* -*- buffer-read-only: t -*- vi: set ro: */ -/* DO NOT EDIT! GENERATED AUTOMATICALLY! */ -/* readlink wrapper to return the link name in malloc'd storage. - Unlike xreadlink and xreadlink_with_size, don't ever call exit. - - Copyright (C) 2001, 2003-2007, 2009-2010 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 . */ - -/* Written by Jim Meyering */ - -#include - -#include "areadlink.h" - -#include -#include -#include -#include -#include - -#ifndef SSIZE_MAX -# define SSIZE_MAX ((ssize_t) (SIZE_MAX / 2)) -#endif - -/* SYMLINK_MAX is used only for an initial memory-allocation sanity - check, so it's OK to guess too small on hosts where there is no - arbitrary limit to symbolic link length. */ -#ifndef SYMLINK_MAX -# define SYMLINK_MAX 1024 -#endif - -#define MAXSIZE (SIZE_MAX < SSIZE_MAX ? SIZE_MAX : SSIZE_MAX) - -/* Call readlink to get the symbolic link value of FILE. - SIZE is a hint as to how long the link is expected to be; - typically it is taken from st_size. It need not be correct. - Return a pointer to that NUL-terminated string in malloc'd storage. - If readlink fails, malloc fails, or if the link value is longer - than SSIZE_MAX, return NULL (caller may use errno to diagnose). */ - -char * -areadlink_with_size (char const *file, size_t size) -{ - /* Some buggy file systems report garbage in st_size. Defend - against them by ignoring outlandish st_size values in the initial - memory allocation. */ - size_t symlink_max = SYMLINK_MAX; - size_t INITIAL_LIMIT_BOUND = 8 * 1024; - size_t initial_limit = (symlink_max < INITIAL_LIMIT_BOUND - ? symlink_max + 1 - : INITIAL_LIMIT_BOUND); - - /* The initial buffer size for the link value. */ - size_t buf_size = size < initial_limit ? size + 1 : initial_limit; - - while (1) - { - ssize_t r; - size_t link_length; - char *buffer = malloc (buf_size); - - if (buffer == NULL) - return NULL; - r = readlink (file, buffer, buf_size); - link_length = r; - - /* On AIX 5L v5.3 and HP-UX 11i v2 04/09, readlink returns -1 - with errno == ERANGE if the buffer is too small. */ - if (r < 0 && errno != ERANGE) - { - int saved_errno = errno; - free (buffer); - errno = saved_errno; - return NULL; - } - - if (link_length < buf_size) - { - buffer[link_length] = 0; - return buffer; - } - - free (buffer); - if (buf_size <= MAXSIZE / 2) - buf_size *= 2; - else if (buf_size < MAXSIZE) - buf_size = MAXSIZE; - else - { - errno = ENOMEM; - return NULL; - } - } -}