/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <android-base/file.h>
#include "fuse_sideload.h"
struct file_data {
int fd; // the underlying sdcard file
uint64_t file_size;
uint32_t block_size;
};
static int read_block_file(void* cookie, uint32_t block, uint8_t* buffer, uint32_t fetch_size) {
file_data* fd = reinterpret_cast<file_data*>(cookie);
off64_t offset = ((off64_t) block) * fd->block_size;
if (TEMP_FAILURE_RETRY(lseek64(fd->fd, offset, SEEK_SET)) == -1) {
fprintf(stderr, "seek on sdcard failed: %s\n", strerror(errno));
return -EIO;
}
if (!android::base::ReadFully(fd->fd, buffer, fetch_size)) {
fprintf(stderr, "read on sdcard failed: %s\n", strerror(errno));
return -EIO;
}
return 0;
}
static void close_file(void* cookie) {
file_data* fd = reinterpret_cast<file_data*>(cookie);
close(fd->fd);
}
bool start_sdcard_fuse(const char* path) {
struct stat sb;
if (stat(path, &sb) == -1) {
fprintf(stderr, "failed to stat %s: %s\n", path, strerror(errno));
return false;
}
file_data fd;
fd.fd = open(path, O_RDONLY);
if (fd.fd == -1) {
fprintf(stderr, "failed to open %s: %s\n", path, strerror(errno));
return false;
}
fd.file_size = sb.st_size;
fd.block_size = 65536;
provider_vtab vtab;
vtab.read_block = read_block_file;
vtab.close = close_file;
// The installation process expects to find the sdcard unmounted.
// Unmount it with MNT_DETACH so that our open file continues to
// work but new references see it as unmounted.
umount2("/sdcard", MNT_DETACH);
return run_fuse_sideload(&vtab, &fd, fd.file_size, fd.block_size) == 0;
}
