112 lines
2.5 KiB
C
112 lines
2.5 KiB
C
|
/*
|
||
|
|
* Copyright (C) 2008 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 <unistd.h>
|
||
|
|
#include <string.h>
|
||
|
|
#include <fcntl.h>
|
||
|
|
#include <sys/mount.h>
|
||
|
|
#include <errno.h>
|
||
|
|
|
||
|
|
#include "sysdeps.h"
|
||
|
|
|
||
|
|
#define TRACE_TAG TRACE_ADB
|
||
|
|
#include "adb.h"
|
||
|
|
|
||
|
|
|
||
|
|
static int system_ro = 1;
|
||
|
|
|
||
|
|
/* Returns the device used to mount a directory in /proc/mounts */
|
||
|
|
static char *find_mount(const char *dir)
|
||
|
|
{
|
||
|
|
int fd;
|
||
|
|
int res;
|
||
|
|
int size;
|
||
|
|
char *token = NULL;
|
||
|
|
const char delims[] = "\n";
|
||
|
|
char buf[4096];
|
||
|
|
|
||
|
|
fd = unix_open("/proc/mounts", O_RDONLY);
|
||
|
|
if (fd < 0)
|
||
|
|
return NULL;
|
||
|
|
|
||
|
|
buf[sizeof(buf) - 1] = '\0';
|
||
|
|
size = adb_read(fd, buf, sizeof(buf) - 1);
|
||
|
|
adb_close(fd);
|
||
|
|
|
||
|
|
token = strtok(buf, delims);
|
||
|
|
|
||
|
|
while (token) {
|
||
|
|
char mount_dev[256];
|
||
|
|
char mount_dir[256];
|
||
|
|
int mount_freq;
|
||
|
|
int mount_passno;
|
||
|
|
|
||
|
|
res = sscanf(token, "%255s %255s %*s %*s %d %d\n",
|
||
|
|
mount_dev, mount_dir, &mount_freq, &mount_passno);
|
||
|
|
mount_dev[255] = 0;
|
||
|
|
mount_dir[255] = 0;
|
||
|
|
if (res == 4 && (strcmp(dir, mount_dir) == 0))
|
||
|
|
return strdup(mount_dev);
|
||
|
|
|
||
|
|
token = strtok(NULL, delims);
|
||
|
|
}
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Init mounts /system as read only, remount to enable writes. */
|
||
|
|
static int remount_system()
|
||
|
|
{
|
||
|
|
char *dev;
|
||
|
|
|
||
|
|
if (system_ro == 0) {
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
dev = find_mount("/system");
|
||
|
|
|
||
|
|
if (!dev)
|
||
|
|
return -1;
|
||
|
|
|
||
|
|
system_ro = mount(dev, "/system", "none", MS_REMOUNT, NULL);
|
||
|
|
|
||
|
|
free(dev);
|
||
|
|
|
||
|
|
return system_ro;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void write_string(int fd, const char* str)
|
||
|
|
{
|
||
|
|
writex(fd, str, strlen(str));
|
||
|
|
}
|
||
|
|
|
||
|
|
void remount_service(int fd, void *cookie)
|
||
|
|
{
|
||
|
|
int ret = remount_system();
|
||
|
|
|
||
|
|
if (!ret)
|
||
|
|
write_string(fd, "remount succeeded\n");
|
||
|
|
else {
|
||
|
|
char buffer[200];
|
||
|
|
snprintf(buffer, sizeof(buffer), "remount failed: %s\n", strerror(errno));
|
||
|
|
write_string(fd, buffer);
|
||
|
|
}
|
||
|
|
|
||
|
|
adb_close(fd);
|
||
|
|
}
|
||
|
|
|