/*-
* 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: src/lib/libarchive/archive_read_open_filename.c,v 1.21 2008/02/19 06:10:48 kientzle Exp $");
#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"
#ifndef O_BINARY
#define O_BINARY 0
#endif
struct read_file_data {
int fd;
size_t block_size;
void *buffer;
mode_t st_mode; /* Mode bits for opened file. */
char can_skip; /* This file supports skipping. */
char filename[1]; /* Must be last! */
};
static int file_close(struct archive *, void *);
static ssize_t file_read(struct archive *, void *, const void **buff);
#if ARCHIVE_API_VERSION < 2
static ssize_t file_skip(struct archive *, void *, size_t request);
#else
static off_t file_skip(struct archive *, void *, off_t request);
#endif
int
archive_read_open_file(struct archive *a, const char *filename,
size_t block_size)
{
return (archive_read_open_filename(a, filename, block_size));
}
int
archive_read_open_filename(struct archive *a, const char *filename,
size_t block_size)
{
struct stat st;
struct read_file_data *mine;
void *b;
int fd;
archive_clear_error(a);
if (filename == NULL || filename[0] == '\0') {
/* We used to invoke archive_read_open_fd(a,0,block_size)
* here, but that doesn't (and shouldn't) handle the
* end-of-file flush when reading stdout from a pipe.
* Basically, read_open_fd() is intended for folks who
* are willing to handle such details themselves. This
* API is intended to be a little smarter for folks who
* want easy handling of the common case.
*/
filename = ""; /* Normalize NULL to "" */
fd = 0;
#if defined(__CYGWIN__) || defined(__BORLANDC__)
setmode(0, O_BINARY);
#elif defined(_WIN32)
_setmode(0, _O_BINARY);
#endif
} else {
fd = open(filename, O_RDONLY | O_BINARY);
if (fd < 0) {
archive_set_error(a, errno,
"Failed to open '%s'", filename);
return (ARCHIVE_FATAL);
}
}
if (fstat(fd, &st) != 0) {
archive_set_error(a, errno, "Can't stat '%s'", filename);
return (ARCHIVE_FATAL);
}
mine = (struct read_file_data *)calloc(1,
sizeof(*mine) + strlen(filename));
b = malloc(block_size);
if (mine == NULL || b == NULL) {
archive_set_error(a, ENOMEM, "No memory");
free(mine);
free(b);
return (ARCHIVE_FATAL);
}
strcpy(mine->filename, filename);
mine->block_size = block_size;
mine->buffer = b;
mine->fd = fd;
/* Remember mode so close can decide whether to flush. */
mine->st_mode = st.st_mode;
/* If we're reading a file from disk, ensure that we don't
overwrite it with an extracted file. */
if (S_ISREG(st.st_mode)) {
archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino);
/*
* Enabling skip here is a performance optimization
* for anything that supports lseek(). On FreeBSD
* (and probably many other systems), only regular
* files and raw disk devices support lseek() (on
* other input types, lseek() returns success but
* doesn't actually change the file pointer, which
* just completely screws up the position-tracking
* logic). In addition, I've yet to find a portable
* way to determine if a device is a raw disk device.
* So I don't see a way to do much better than to only
* enable this optimization for regular files.
*/
mine->can_skip = 1;
}
return (archive_read_open2(a, mine,
NULL, file_read, file_skip, file_close));
}
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;
ssize_t bytes_read;
*buff = mine->buffer;
bytes_read = read(mine->fd, mine->buffer, mine->block_size);
if (bytes_read < 0) {
if (mine->filename[0] == '\0')
archive_set_error(a, errno, "Error reading stdin");
else
archive_set_error(a, errno, "Error reading '%s'",
mine->filename);
}
return (bytes_read);
}
#if ARCHIVE_API_VERSION < 2
static ssize_t
file_skip(struct archive *a, void *client_data, size_t request)
#else
static off_t
file_skip(struct archive *a, void *client_data, off_t request)
#endif
{
struct read_file_data *mine = (struct read_file_data *)client_data;
off_t old_offset, new_offset;
if (!mine->can_skip) /* We can't skip, so ... */
return (0); /* ... skip zero bytes. */
/* Reduce request to the next smallest multiple of block_size */
request = (request / mine->block_size) * mine->block_size;
if (request == 0)
return (0);
/*
* Hurray for lazy evaluation: if the first lseek fails, the second
* one will not be executed.
*/
if (((old_offset = lseek(mine->fd, 0, SEEK_CUR)) < 0) ||
((new_offset = lseek(mine->fd, request, SEEK_CUR)) < 0))
{
/* If skip failed once, it will probably fail again. */
mine->can_skip = 0;
if (errno == ESPIPE)
{
/*
* Failure to lseek() can be caused by the file
* descriptor pointing to a pipe, socket or FIFO.
* Return 0 here, so the compression layer will use
* read()s instead to advance the file descriptor.
* It's slower of course, but works as well.
*/
return (0);
}
/*
* There's been an error other than ESPIPE. This is most
* likely caused by a programmer error (too large request)
* or a corrupted archive file.
*/
if (mine->filename[0] == '\0')
/*
* Should never get here, since lseek() on stdin ought
* to return an ESPIPE error.
*/
archive_set_error(a, errno, "Error seeking in stdin");
else
archive_set_error(a, errno, "Error seeking in '%s'",
mine->filename);
return (-1);
}
return (new_offset - old_offset);
}
static int
file_close(struct archive *a, void *client_data)
{
struct read_file_data *mine = (struct read_file_data *)client_data;
(void)a; /* UNUSED */
/* Only flush and close if open succeeded. */
if (mine->fd >= 0) {
/*
* Sometimes, we should flush the input before closing.
* Regular files: faster to just close without flush.
* Devices: must not flush (user might need to
* read the "next" item on a non-rewind device).
* Pipes and sockets: must flush (otherwise, the
* program feeding the pipe or socket may complain).
* Here, I flush everything except for regular files and
* device nodes.
*/
if (!S_ISREG(mine->st_mode)
&& !S_ISCHR(mine->st_mode)
&& !S_ISBLK(mine->st_mode)) {
ssize_t bytesRead;
do {
bytesRead = read(mine->fd, mine->buffer,
mine->block_size);
} while (bytesRead > 0);
}
/* If a named file was opened, then it needs to be closed. */
if (mine->filename[0] != '\0')
close(mine->fd);
}
free(mine->buffer);
free(mine);
return (ARCHIVE_OK);
}