1 /* 2 * Copyright (C) 2007 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "mounts.h" 18 19 #include <errno.h> 20 #include <fcntl.h> 21 #include <mntent.h> 22 #include <stdio.h> 23 #include <stdlib.h> 24 #include <string.h> 25 #include <sys/mount.h> 26 27 #include <string> 28 #include <vector> 29 30 #include <android-base/logging.h> 31 32 struct MountedVolume { 33 std::string device; 34 std::string mount_point; 35 std::string filesystem; 36 std::string flags; 37 }; 38 39 static std::vector<MountedVolume*> g_mounts_state; 40 scan_mounted_volumes()41bool scan_mounted_volumes() { 42 for (size_t i = 0; i < g_mounts_state.size(); ++i) { 43 delete g_mounts_state[i]; 44 } 45 g_mounts_state.clear(); 46 47 // Open and read mount table entries. 48 FILE* fp = setmntent("/proc/mounts", "re"); 49 if (fp == NULL) { 50 return false; 51 } 52 mntent* e; 53 while ((e = getmntent(fp)) != NULL) { 54 MountedVolume* v = new MountedVolume; 55 v->device = e->mnt_fsname; 56 v->mount_point = e->mnt_dir; 57 v->filesystem = e->mnt_type; 58 v->flags = e->mnt_opts; 59 g_mounts_state.push_back(v); 60 } 61 endmntent(fp); 62 return true; 63 } 64 find_mounted_volume_by_mount_point(const char * mount_point)65MountedVolume* find_mounted_volume_by_mount_point(const char* mount_point) { 66 for (size_t i = 0; i < g_mounts_state.size(); ++i) { 67 if (g_mounts_state[i]->mount_point == mount_point) return g_mounts_state[i]; 68 } 69 return nullptr; 70 } 71 unmount_mounted_volume(MountedVolume * volume)72int unmount_mounted_volume(MountedVolume* volume) { 73 // Intentionally pass the empty string to umount if the caller tries to unmount a volume they 74 // already unmounted using this function. 75 std::string mount_point = volume->mount_point; 76 volume->mount_point.clear(); 77 int result = umount(mount_point.c_str()); 78 if (result == -1) { 79 PLOG(WARNING) << "Failed to umount " << mount_point; 80 } 81 return result; 82 } 83