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/*-
* Copyright (c) 2003-2010 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_filename.c 201093 2009-12-28 02:28:44Z kientzle $");
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#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
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
#include <sys/disk.h>
#elif defined(__NetBSD__) || defined(__OpenBSD__)
#include <sys/disklabel.h>
#include <sys/dkio.h>
#elif defined(__DragonFly__)
#include <sys/diskslice.h>
#endif
#include "archive.h"
#include "archive_private.h"
#include "archive_string.h"
#ifndef O_BINARY
#define O_BINARY 0
#endif
#ifndef O_CLOEXEC
#define O_CLOEXEC 0
#endif
struct read_file_data {
int fd;
size_t block_size;
void *buffer;
mode_t st_mode; /* Mode bits for opened file. */
char use_lseek;
enum fnt_e { FNT_STDIN, FNT_MBS, FNT_WCS } filename_type;
union {
char m[1];/* MBS filename. */
wchar_t w[1];/* WCS filename. */
} filename; /* Must be last! */
};
static int file_open(struct archive *, void *);
static int file_close(struct archive *, void *);
static int file_close2(struct archive *, void *);
static int file_switch(struct archive *, void *, void *);
static ssize_t file_read(struct archive *, void *, const void **buff);
static int64_t file_seek(struct archive *, void *, int64_t request, int);
static int64_t file_skip(struct archive *, void *, int64_t request);
static int64_t file_skip_lseek(struct archive *, void *, int64_t request);
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)
{
const char *filenames[2];
filenames[0] = filename;
filenames[1] = NULL;
return archive_read_open_filenames(a, filenames, block_size);
}
int
archive_read_open_filenames(struct archive *a, const char **filenames,
size_t block_size)
{
struct read_file_data *mine;
const char *filename = NULL;
if (filenames)
filename = *(filenames++);
archive_clear_error(a);
do
{
if (filename == NULL)
filename = "";
mine = (struct read_file_data *)calloc(1,
sizeof(*mine) + strlen(filename));
if (mine == NULL)
goto no_memory;
strcpy(mine->filename.m, filename);
mine->block_size = block_size;
mine->fd = -1;
mine->buffer = NULL;
mine->st_mode = mine->use_lseek = 0;
if (filename == NULL || filename[0] == '\0') {
mine->filename_type = FNT_STDIN;
} else
mine->filename_type = FNT_MBS;
if (archive_read_append_callback_data(a, mine) != (ARCHIVE_OK))
return (ARCHIVE_FATAL);
if (filenames == NULL)
break;
filename = *(filenames++);
} while (filename != NULL && filename[0] != '\0');
archive_read_set_open_callback(a, file_open);
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_switch_callback(a, file_switch);
archive_read_set_seek_callback(a, file_seek);
return (archive_read_open1(a));
no_memory:
archive_set_error(a, ENOMEM, "No memory");
return (ARCHIVE_FATAL);
}
int
archive_read_open_filename_w(struct archive *a, const wchar_t *wfilename,
size_t block_size)
{
struct read_file_data *mine = (struct read_file_data *)calloc(1,
sizeof(*mine) + wcslen(wfilename) * sizeof(wchar_t));
if (!mine)
{
archive_set_error(a, ENOMEM, "No memory");
return (ARCHIVE_FATAL);
}
mine->fd = -1;
mine->block_size = block_size;
if (wfilename == NULL || wfilename[0] == L'\0') {
mine->filename_type = FNT_STDIN;
} else {
#if defined(_WIN32) && !defined(__CYGWIN__)
mine->filename_type = FNT_WCS;
wcscpy(mine->filename.w, wfilename);
#else
/*
* POSIX system does not support a wchar_t interface for
* open() system call, so we have to translate a wchar_t
* filename to multi-byte one and use it.
*/
struct archive_string fn;
archive_string_init(&fn);
if (archive_string_append_from_wcs(&fn, wfilename,
wcslen(wfilename)) != 0) {
if (errno == ENOMEM)
archive_set_error(a, errno,
"Can't allocate memory");
else
archive_set_error(a, EINVAL,
"Failed to convert a wide-character"
" filename to a multi-byte filename");
archive_string_free(&fn);
free(mine);
return (ARCHIVE_FATAL);
}
mine->filename_type = FNT_MBS;
strcpy(mine->filename.m, fn.s);
archive_string_free(&fn);
#endif
}
if (archive_read_append_callback_data(a, mine) != (ARCHIVE_OK))
return (ARCHIVE_FATAL);
archive_read_set_open_callback(a, file_open);
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_switch_callback(a, file_switch);
archive_read_set_seek_callback(a, file_seek);
return (archive_read_open1(a));
}
static int
file_open(struct archive *a, void *client_data)
{
struct stat st;
struct read_file_data *mine = (struct read_file_data *)client_data;
void *buffer;
const char *filename = NULL;
const wchar_t *wfilename = NULL;
int fd = -1;
int is_disk_like = 0;
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
off_t mediasize = 0; /* FreeBSD-specific, so off_t okay here. */
#elif defined(__NetBSD__) || defined(__OpenBSD__)
struct disklabel dl;
#elif defined(__DragonFly__)
struct partinfo pi;
#endif
archive_clear_error(a);
if (mine->filename_type == FNT_STDIN) {
/* We used to delegate stdin support by
* directly calling 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.
*/
fd = 0;
#if defined(__CYGWIN__) || defined(_WIN32)
setmode(0, O_BINARY);
#endif
filename = "";
} else if (mine->filename_type == FNT_MBS) {
filename = mine->filename.m;
fd = open(filename, O_RDONLY | O_BINARY | O_CLOEXEC);
__archive_ensure_cloexec_flag(fd);
if (fd < 0) {
archive_set_error(a, errno,
"Failed to open '%s'", filename);
return (ARCHIVE_FATAL);
}
} else {
#if defined(_WIN32) && !defined(__CYGWIN__)
wfilename = mine->filename.w;
fd = _wopen(wfilename, O_RDONLY | O_BINARY);
if (fd < 0 && errno == ENOENT) {
wchar_t *fullpath;
fullpath = __la_win_permissive_name_w(wfilename);
if (fullpath != NULL) {
fd = _wopen(fullpath, O_RDONLY | O_BINARY);
free(fullpath);
}
}
if (fd < 0) {
archive_set_error(a, errno,
"Failed to open '%S'", wfilename);
return (ARCHIVE_FATAL);
}
#else
archive_set_error(a, ARCHIVE_ERRNO_MISC,
"Unexpedted operation in archive_read_open_filename");
goto fail;
#endif
}
if (fstat(fd, &st) != 0) {
if (mine->filename_type == FNT_WCS)
archive_set_error(a, errno, "Can't stat '%S'",
wfilename);
else
archive_set_error(a, errno, "Can't stat '%s'",
filename);
goto fail;
}
/*
* Determine whether the input looks like a disk device or a
* tape device. The results are used below to select an I/O
* strategy:
* = "disk-like" devices support arbitrary lseek() and will
* support I/O requests of any size. So we get easy skipping
* and can cheat on block sizes to get better performance.
* = "tape-like" devices require strict blocking and use
* specialized ioctls for seeking.
* = "socket-like" devices cannot seek at all but can improve
* performance by using nonblocking I/O to read "whatever is
* available right now".
*
* Right now, we only specially recognize disk-like devices,
* but it should be straightforward to add probes and strategy
* here for tape-like and socket-like devices.
*/
if (S_ISREG(st.st_mode)) {
/* Safety: Tell the extractor not to overwrite the input. */
archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino);
/* Regular files act like disks. */
is_disk_like = 1;
}
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
/* FreeBSD: if it supports DIOCGMEDIASIZE ioctl, it's disk-like. */
else if (S_ISCHR(st.st_mode) &&
ioctl(fd, DIOCGMEDIASIZE, &mediasize) == 0 &&
mediasize > 0) {
is_disk_like = 1;
}
#elif defined(__NetBSD__) || defined(__OpenBSD__)
/* Net/OpenBSD: if it supports DIOCGDINFO ioctl, it's disk-like. */
else if ((S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode)) &&
ioctl(fd, DIOCGDINFO, &dl) == 0 &&
dl.d_partitions[DISKPART(st.st_rdev)].p_size > 0) {
is_disk_like = 1;
}
#elif defined(__DragonFly__)
/* DragonFly BSD: if it supports DIOCGPART ioctl, it's disk-like. */
else if (S_ISCHR(st.st_mode) &&
ioctl(fd, DIOCGPART, &pi) == 0 &&
pi.media_size > 0) {
is_disk_like = 1;
}
#elif defined(__linux__)
/* Linux: All block devices are disk-like. */
else if (S_ISBLK(st.st_mode) &&
lseek(fd, 0, SEEK_CUR) == 0 &&
lseek(fd, 0, SEEK_SET) == 0 &&
lseek(fd, 0, SEEK_END) > 0 &&
lseek(fd, 0, SEEK_SET) == 0) {
is_disk_like = 1;
}
#endif
/* TODO: Add an "is_tape_like" variable and appropriate tests. */
/* Disk-like devices prefer power-of-two block sizes. */
/* Use provided block_size as a guide so users have some control. */
if (is_disk_like) {
size_t new_block_size = 64 * 1024;
while (new_block_size < mine->block_size
&& new_block_size < 64 * 1024 * 1024)
new_block_size *= 2;
mine->block_size = new_block_size;
}
buffer = malloc(mine->block_size);
if (buffer == NULL) {
archive_set_error(a, ENOMEM, "No memory");
goto fail;
}
mine->buffer = buffer;
mine->fd = fd;
/* Remember mode so close can decide whether to flush. */
mine->st_mode = st.st_mode;
/* Disk-like inputs can use lseek(). */
if (is_disk_like)
mine->use_lseek = 1;
return (ARCHIVE_OK);
fail:
/*
* Don't close file descriptors not opened or ones pointing referring
* to `FNT_STDIN`.
*/
if (fd != -1 && fd != 0)
close(fd);
return (ARCHIVE_FATAL);
}
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;
/* TODO: If a recent lseek() operation has left us
* mis-aligned, read and return a short block to try to get
* us back in alignment. */
/* TODO: Someday, try mmap() here; if that succeeds, give
* the entire file to libarchive as a single block. That
* could be a lot faster than block-by-block manual I/O. */
/* TODO: We might be able to improve performance on pipes and
* sockets by setting non-blocking I/O and just accepting
* whatever we get here instead of waiting for a full block
* worth of data. */
*buff = mine->buffer;
for (;;) {
bytes_read = read(mine->fd, mine->buffer, mine->block_size);
if (bytes_read < 0) {
if (errno == EINTR)
continue;
else if (mine->filename_type == FNT_STDIN)
archive_set_error(a, errno,
"Error reading stdin");
else if (mine->filename_type == FNT_MBS)
archive_set_error(a, errno,
"Error reading '%s'", mine->filename.m);
else
archive_set_error(a, errno,
"Error reading '%S'", mine->filename.w);
}
return (bytes_read);
}
}
/*
* Regular files and disk-like block devices can use simple lseek
* without needing to round the request to the block size.
*
* TODO: This can leave future reads mis-aligned. Since we know the
* offset here, we should store it and use it in file_read() above
* to determine whether we should perform a short read to get back
* into alignment. Long series of mis-aligned reads can negatively
* impact disk throughput. (Of course, the performance impact should
* be carefully tested; extra code complexity is only worthwhile if
* it does provide measurable improvement.)
*
* TODO: Be lazy about the actual seek. There are a few pathological
* cases where libarchive makes a bunch of seek requests in a row
* without any intervening reads. This isn't a huge performance
* problem, since the kernel handles seeks lazily already, but
* it would be very slightly faster if we simply remembered the
* seek request here and then actually performed the seek at the
* top of the read callback above.
*/
static int64_t
file_skip_lseek(struct archive *a, void *client_data, int64_t request)
{
struct read_file_data *mine = (struct read_file_data *)client_data;
#if defined(_WIN32) && !defined(__CYGWIN__)
/* We use _lseeki64() on Windows. */
int64_t old_offset, new_offset;
#else
off_t old_offset, new_offset;
#endif
/* We use off_t here because lseek() is declared that way. */
/* TODO: Deal with case where off_t isn't 64 bits.
* This shouldn't be a problem on Linux or other POSIX
* systems, since the configuration logic for libarchive
* tries to obtain a 64-bit off_t.
*/
if ((old_offset = lseek(mine->fd, 0, SEEK_CUR)) >= 0 &&
(new_offset = lseek(mine->fd, request, SEEK_CUR)) >= 0)
return (new_offset - old_offset);
/* If lseek() fails, don't bother trying again. */
mine->use_lseek = 0;
/* Let libarchive recover with read+discard */
if (errno == ESPIPE)
return (0);
/* If the input is corrupted or truncated, fail. */
if (mine->filename_type == FNT_STDIN)
archive_set_error(a, errno, "Error seeking in stdin");
else if (mine->filename_type == FNT_MBS)
archive_set_error(a, errno, "Error seeking in '%s'",
mine->filename.m);
else
archive_set_error(a, errno, "Error seeking in '%S'",
mine->filename.w);
return (-1);
}
/*
* TODO: Implement another file_skip_XXXX that uses MTIO ioctls to
* accelerate operation on tape drives.
*/
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;
/* Delegate skip requests. */
if (mine->use_lseek)
return (file_skip_lseek(a, client_data, request));
/* If we can't skip, return 0; libarchive will read+discard instead. */
return (0);
}
/*
* TODO: Store the offset and use it in the read callback.
*/
static int64_t
file_seek(struct archive *a, void *client_data, int64_t request, int whence)
{
struct read_file_data *mine = (struct read_file_data *)client_data;
int64_t r;
/* We use off_t here because lseek() is declared that way. */
/* See above for notes about when off_t is less than 64 bits. */
r = lseek(mine->fd, request, whence);
if (r >= 0)
return r;
/* If the input is corrupted or truncated, fail. */
if (mine->filename_type == FNT_STDIN)
archive_set_error(a, errno, "Error seeking in stdin");
else if (mine->filename_type == FNT_MBS)
archive_set_error(a, errno, "Error seeking in '%s'",
mine->filename.m);
else
archive_set_error(a, errno, "Error seeking in '%S'",
mine->filename.w);
return (ARCHIVE_FATAL);
}
static int
file_close2(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.
* Disk-like devices: Ditto.
* Tapes: 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_type != FNT_STDIN)
close(mine->fd);
}
free(mine->buffer);
mine->buffer = NULL;
mine->fd = -1;
return (ARCHIVE_OK);
}
static int
file_close(struct archive *a, void *client_data)
{
struct read_file_data *mine = (struct read_file_data *)client_data;
file_close2(a, client_data);
free(mine);
return (ARCHIVE_OK);
}
static int
file_switch(struct archive *a, void *client_data1, void *client_data2)
{
file_close2(a, client_data1);
return file_open(a, client_data2);
}