/*
* 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 <errno.h>
#include <pthread.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.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) {
struct file_data* fd = (struct file_data*)cookie;
if (lseek(fd->fd, block * fd->block_size, SEEK_SET) < 0) {
printf("seek on sdcard failed: %s\n", strerror(errno));
return -EIO;
}
while (fetch_size > 0) {
ssize_t r = read(fd->fd, buffer, fetch_size);
if (r < 0) {
if (r != -EINTR) {
printf("read on sdcard failed: %s\n", strerror(errno));
return -EIO;
}
r = 0;
}
fetch_size -= r;
buffer += r;
}
return 0;
}
static void close_file(void* cookie) {
struct file_data* fd = (struct file_data*)cookie;
close(fd->fd);
}
struct token {
pthread_t th;
const char* path;
int result;
};
static void* run_sdcard_fuse(void* cookie) {
struct token* t = (struct token*)cookie;
struct stat sb;
if (stat(t->path, &sb) < 0) {
fprintf(stderr, "failed to stat %s: %s\n", t->path, strerror(errno));
t->result = -1;
return NULL;
}
struct file_data fd;
struct provider_vtab vtab;
fd.fd = open(t->path, O_RDONLY);
if (fd.fd < 0) {
fprintf(stderr, "failed to open %s: %s\n", t->path, strerror(errno));
t->result = -1;
return NULL;
}
fd.file_size = sb.st_size;
fd.block_size = 65536;
vtab.read_block = read_block_file;
vtab.close = close_file;
t->result = run_fuse_sideload(&vtab, &fd, fd.file_size, fd.block_size);
return NULL;
}
// How long (in seconds) we wait for the fuse-provided package file to
// appear, before timing out.
#define SDCARD_INSTALL_TIMEOUT 10
void* start_sdcard_fuse(const char* path) {
struct token* t = malloc(sizeof(struct token));
t->path = path;
pthread_create(&(t->th), NULL, run_sdcard_fuse, t);
struct stat st;
int i;
for (i = 0; i < SDCARD_INSTALL_TIMEOUT; ++i) {
if (stat(FUSE_SIDELOAD_HOST_PATHNAME, &st) != 0) {
if (errno == ENOENT && i < SDCARD_INSTALL_TIMEOUT-1) {
sleep(1);
continue;
} else {
return NULL;
}
}
}
// 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 t;
}
void finish_sdcard_fuse(void* cookie) {
if (cookie == NULL) return;
struct token* t = (struct token*)cookie;
// Calling stat() on this magic filename signals the fuse
// filesystem to shut down.
struct stat st;
stat(FUSE_SIDELOAD_HOST_EXIT_PATHNAME, &st);
pthread_join(t->th, NULL);
free(t);
}
