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.

Change-Id: Ic82d929e052b5ba70ecf7b475e0a223d77d9687e

1 files changed, 88 insertions, 0 deletions

diff --git a/volume_manager/Utils.h b/volume_manager/Utils.h
new file mode 100644
index 00000000..94ca6e70
--- /dev/null
+++ b/volume_manager/Utils.h
@@ -0,0 +1,88 @@
+/*
+ * 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.
+ */
+
+#ifndef ANDROID_VOLMGR_UTILS_H
+#define ANDROID_VOLMGR_UTILS_H
+
+#include <cutils/multiuser.h>
+#include <selinux/selinux.h>
+#include <utils/Errors.h>
+
+#include <chrono>
+#include <string>
+#include <vector>
+
+// DISALLOW_COPY_AND_ASSIGN disallows the copy and operator= functions. It goes in the private:
+// declarations in a class.
+#if !defined(DISALLOW_COPY_AND_ASSIGN)
+#define DISALLOW_COPY_AND_ASSIGN(TypeName) \
+    TypeName(const TypeName&) = delete;    \
+    void operator=(const TypeName&) = delete
+#endif
+
+struct DIR;
+
+namespace android {
+namespace volmgr {
+
+/* SELinux contexts used depending on the block device type */
+extern security_context_t sBlkidContext;
+extern security_context_t sBlkidUntrustedContext;
+extern security_context_t sFsckContext;
+extern security_context_t sFsckUntrustedContext;
+
+status_t CreateDeviceNode(const std::string& path, dev_t dev);
+status_t DestroyDeviceNode(const std::string& path);
+
+/* fs_prepare_dir wrapper that creates with SELinux context */
+status_t PrepareDir(const std::string& path, mode_t mode, uid_t uid, gid_t gid);
+
+/* Really unmounts the path, killing active processes along the way */
+status_t ForceUnmount(const std::string& path, bool detach = false);
+
+/* Kills any processes using given path */
+status_t KillProcessesUsingPath(const std::string& path);
+
+/* Creates bind mount from source to target */
+status_t BindMount(const std::string& source, const std::string& target);
+
+/* Reads filesystem metadata from device at path */
+status_t ReadMetadata(const std::string& path, std::string& fsType, std::string& fsUuid,
+                      std::string& fsLabel);
+
+/* Reads filesystem metadata from untrusted device at path */
+status_t ReadMetadataUntrusted(const std::string& path, std::string& fsType, std::string& fsUuid,
+                               std::string& fsLabel);
+
+/* Returns either WEXITSTATUS() status, or a negative errno */
+status_t ForkExecvp(const std::vector<std::string>& args);
+status_t ForkExecvp(const std::vector<std::string>& args, security_context_t context);
+
+bool IsFilesystemSupported(const std::string& fsType);
+
+/* Wipes contents of block device at given path */
+status_t WipeBlockDevice(const std::string& path);
+
+dev_t GetDevice(const std::string& path);
+
+/* Checks if Android is running in QEMU */
+bool IsRunningInEmulator();
+
+}  // namespace volmgr
+}  // namespace android
+
+#endif