recovery: Implement a volume manager

This is a copy of the pre-binderized vold which has been converted to
use direct calls instead of sockets and stripped down to only what is
needed to support recovery.

Includes:
  * recovery: volmgr: remove unused IsSupported

    Change-Id: If8206658fdfb6108221806c09c99bf0a30f4a586
    Signed-off-by: Jesse Chan <jc@lineageos.org>

  * recovery: volmgr: remove filesystem checks

    Those checks are not strictly necessary and we are
    not building fsck tools for recovery for now.

    Remove those checks so volmgr can be useful.

    Change-Id: I87756c61b933b6cdccd281c6276b686fbd36019f
    Signed-off-by: Jesse Chan <jc@lineageos.org>

  * recovery: fixup `EmulatedVolume creating`

    Avoid dangling pointer. Instead of pointing to FstabEntry create copy.

    Change-Id: I57f76006db09a6add2c173f43175f0f6b848d87b

  * recovery: fix volmgr cleaning up

    Don't reset pointer to netlink manager
    Delete disks in stop() rather then in ~VolumeManager
    Call destroy() before deleting disks cause delete expects the
      disk to be destroyed
    Clear the lists or we would read garbage data on the next scan

    Change-Id: Idadfa1f33b7cb5f2f3c780848a99344a6608420e

  * recovery: handle interrupts in apply update menu

    Change-Id: I1f78f9196634353b77986545332d7d52a5f0c161

Change-Id: Ic82d929e052b5ba70ecf7b475e0a223d77d9687e
diff --git a/volume_manager/PublicVolume.cpp b/volume_manager/PublicVolume.cpp
new file mode 100644
index 0000000..8fb3b96
--- /dev/null
+++ b/volume_manager/PublicVolume.cpp
@@ -0,0 +1,133 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * Copyright (C) 2019 The LineageOS 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 "PublicVolume.h"
+#include <volume_manager/ResponseCode.h>
+#include <volume_manager/VolumeManager.h>
+#include "Utils.h"
+#include "fs/Exfat.h"
+#include "fs/Ext4.h"
+#include "fs/F2fs.h"
+#include "fs/Ntfs.h"
+#include "fs/Vfat.h"
+
+#include <android-base/logging.h>
+#include <android-base/stringprintf.h>
+#include <cutils/fs.h>
+#include <private/android_filesystem_config.h>
+
+#include <fcntl.h>
+#include <stdlib.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/sysmacros.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+using android::base::StringPrintf;
+
+namespace android {
+namespace volmgr {
+
+PublicVolume::PublicVolume(dev_t device, const std::string& nickname,
+                           const std::string& fstype /* = "" */,
+                           const std::string& mntopts /* = "" */)
+    : VolumeBase(Type::kPublic), mDevice(device), mFsType(fstype), mMntOpts(mntopts) {
+    setId(StringPrintf("public:%u_%u", major(device), minor(device)));
+    setPartLabel(nickname);
+    mDevPath = StringPrintf("/dev/block/volmgr/%s", getId().c_str());
+}
+
+PublicVolume::~PublicVolume() {}
+
+status_t PublicVolume::readMetadata() {
+    std::string label;
+    status_t res = ReadMetadataUntrusted(mDevPath, mFsType, mFsUuid, label);
+    if (!label.empty()) {
+        setPartLabel(label);
+    }
+    VolumeManager::Instance()->notifyEvent(ResponseCode::VolumeFsTypeChanged, mFsType);
+    VolumeManager::Instance()->notifyEvent(ResponseCode::VolumeFsUuidChanged, mFsUuid);
+    return res;
+}
+
+status_t PublicVolume::doCreate() {
+    status_t res = CreateDeviceNode(mDevPath, mDevice);
+    if (res != OK) {
+        return res;
+    }
+    readMetadata();
+
+    // Use UUID as stable name, if available
+    std::string stableName = getId();
+    if (!mFsUuid.empty()) {
+        stableName = mFsUuid;
+    }
+    setPath(StringPrintf("/storage/%s", stableName.c_str()));
+
+    return OK;
+}
+
+status_t PublicVolume::doDestroy() {
+    return DestroyDeviceNode(mDevPath);
+}
+
+status_t PublicVolume::doMount() {
+    if (!IsFilesystemSupported(mFsType)) {
+        LOG(ERROR) << getId() << " unsupported filesystem " << mFsType;
+        return -EIO;
+    }
+
+    if (fs_prepare_dir(getPath().c_str(), 0700, AID_ROOT, AID_ROOT)) {
+        PLOG(ERROR) << getId() << " failed to create mount points";
+        return -errno;
+    }
+
+    int ret = 0;
+    if (mFsType == "exfat") {
+        ret = exfat::Mount(mDevPath, getPath(), AID_MEDIA_RW, AID_MEDIA_RW, 0007);
+    } else if (mFsType == "ext4") {
+        ret = ext4::Mount(mDevPath, getPath(), false, false, true, mMntOpts, false, true);
+    } else if (mFsType == "f2fs") {
+        ret = f2fs::Mount(mDevPath, getPath(), mMntOpts, false, true);
+    } else if (mFsType == "ntfs") {
+        ret =
+            ntfs::Mount(mDevPath, getPath(), false, false, false, AID_MEDIA_RW, AID_MEDIA_RW, 0007);
+    } else if (mFsType == "vfat") {
+        ret = vfat::Mount(mDevPath, getPath(), false, false, false, AID_MEDIA_RW, AID_MEDIA_RW,
+                          0007, true);
+    } else {
+        ret = ::mount(mDevPath.c_str(), getPath().c_str(), mFsType.c_str(), 0, nullptr);
+    }
+    if (ret) {
+        PLOG(ERROR) << getId() << " failed to mount " << mDevPath;
+        return -EIO;
+    }
+
+    return OK;
+}
+
+status_t PublicVolume::doUnmount(bool detach /* = false */) {
+    ForceUnmount(getPath(), detach);
+
+    rmdir(getPath().c_str());
+
+    return OK;
+}
+
+}  // namespace volmgr
+}  // namespace android