ghcup-hs/3rdparty/libarchive/c/archive_read_open_file.c

181 lines
5.0 KiB
C

/*-
* Copyright (c) 2003-2007 Tim Kientzle
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "archive_platform.h"
__FBSDID("$FreeBSD: head/lib/libarchive/archive_read_open_file.c 201093 2009-12-28 02:28:44Z kientzle $");
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_IO_H
#include <io.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include "archive.h"
struct read_FILE_data {
FILE *f;
size_t block_size;
void *buffer;
char can_skip;
};
static int file_close(struct archive *, void *);
static ssize_t file_read(struct archive *, void *, const void **buff);
static int64_t file_skip(struct archive *, void *, int64_t request);
int
archive_read_open_FILE(struct archive *a, FILE *f)
{
struct stat st;
struct read_FILE_data *mine;
size_t block_size = 128 * 1024;
void *b;
archive_clear_error(a);
mine = (struct read_FILE_data *)malloc(sizeof(*mine));
b = malloc(block_size);
if (mine == NULL || b == NULL) {
archive_set_error(a, ENOMEM, "No memory");
free(mine);
free(b);
return (ARCHIVE_FATAL);
}
mine->block_size = block_size;
mine->buffer = b;
mine->f = f;
/*
* If we can't fstat() the file, it may just be that it's not
* a file. (On some platforms, FILE * objects can wrap I/O
* streams that don't support fileno()). As a result, fileno()
* should be used cautiously.)
*/
if (fstat(fileno(mine->f), &st) == 0 && S_ISREG(st.st_mode)) {
archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino);
/* Enable the seek optimization only for regular files. */
mine->can_skip = 1;
} else
mine->can_skip = 0;
#if defined(__CYGWIN__) || defined(_WIN32)
setmode(fileno(mine->f), O_BINARY);
#endif
archive_read_set_read_callback(a, file_read);
archive_read_set_skip_callback(a, file_skip);
archive_read_set_close_callback(a, file_close);
archive_read_set_callback_data(a, mine);
return (archive_read_open1(a));
}
static ssize_t
file_read(struct archive *a, void *client_data, const void **buff)
{
struct read_FILE_data *mine = (struct read_FILE_data *)client_data;
size_t bytes_read;
*buff = mine->buffer;
bytes_read = fread(mine->buffer, 1, mine->block_size, mine->f);
if (bytes_read < mine->block_size && ferror(mine->f)) {
archive_set_error(a, errno, "Error reading file");
}
return (bytes_read);
}
static int64_t
file_skip(struct archive *a, void *client_data, int64_t request)
{
struct read_FILE_data *mine = (struct read_FILE_data *)client_data;
#if HAVE_FSEEKO
off_t skip = (off_t)request;
#elif HAVE__FSEEKI64
int64_t skip = request;
#else
long skip = (long)request;
#endif
int skip_bits = sizeof(skip) * 8 - 1;
(void)a; /* UNUSED */
/*
* If we can't skip, return 0 as the amount we did step and
* the caller will work around by reading and discarding.
*/
if (!mine->can_skip)
return (0);
if (request == 0)
return (0);
/* If request is too big for a long or an off_t, reduce it. */
if (sizeof(request) > sizeof(skip)) {
int64_t max_skip =
(((int64_t)1 << (skip_bits - 1)) - 1) * 2 + 1;
if (request > max_skip)
skip = max_skip;
}
#ifdef __ANDROID__
/* fileno() isn't safe on all platforms ... see above. */
if (lseek(fileno(mine->f), skip, SEEK_CUR) < 0)
#elif HAVE_FSEEKO
if (fseeko(mine->f, skip, SEEK_CUR) != 0)
#elif HAVE__FSEEKI64
if (_fseeki64(mine->f, skip, SEEK_CUR) != 0)
#else
if (fseek(mine->f, skip, SEEK_CUR) != 0)
#endif
{
mine->can_skip = 0;
return (0);
}
return (request);
}
static int
file_close(struct archive *a, void *client_data)
{
struct read_FILE_data *mine = (struct read_FILE_data *)client_data;
(void)a; /* UNUSED */
free(mine->buffer);
free(mine);
return (ARCHIVE_OK);
}