Revert "Revert "Convert BootControl HAL to binder.""

This reverts commit 9ca8231d34dc134deaf16bcfb112a04cea8ff6d5.

Bug: 31864052
Test: Built and confirmed UE runs successfully on boot on marlin.
Change-Id: I0b231f58265f23c6673632a4c2477c8de272a096
Signed-off-by: Connor O'Brien <connoro@google.com>
diff --git a/boot_control_recovery.cc b/boot_control_recovery.cc
new file mode 100644
index 0000000..39b5ff1
--- /dev/null
+++ b/boot_control_recovery.cc
@@ -0,0 +1,182 @@
+//
+// Copyright (C) 2015 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 "update_engine/boot_control_recovery.h"
+
+#include <base/bind.h>
+#include <base/files/file_util.h>
+#include <base/logging.h>
+#include <base/strings/string_util.h>
+#include <brillo/make_unique_ptr.h>
+#include <brillo/message_loops/message_loop.h>
+
+#include "update_engine/common/utils.h"
+#include "update_engine/utils_android.h"
+
+using std::string;
+
+#ifndef _UE_SIDELOAD
+#error "BootControlRecovery should only be used for update_engine_sideload."
+#endif
+
+// When called from update_engine_sideload, we don't attempt to dynamically load
+// the right boot_control HAL, instead we use the only HAL statically linked in
+// via the PRODUCT_STATIC_BOOT_CONTROL_HAL make variable and access the module
+// struct directly.
+extern const hw_module_t HAL_MODULE_INFO_SYM;
+
+namespace chromeos_update_engine {
+
+namespace boot_control {
+
+// Factory defined in boot_control.h.
+std::unique_ptr<BootControlInterface> CreateBootControl() {
+  std::unique_ptr<BootControlRecovery> boot_control(new BootControlRecovery());
+  if (!boot_control->Init()) {
+    return nullptr;
+  }
+  return std::move(boot_control);
+}
+
+}  // namespace boot_control
+
+bool BootControlRecovery::Init() {
+  const hw_module_t* hw_module;
+  int ret;
+
+  // For update_engine_sideload, we simulate the hw_get_module() by accessing it
+  // from the current process directly.
+  hw_module = &HAL_MODULE_INFO_SYM;
+  ret = 0;
+  if (!hw_module ||
+      strcmp(BOOT_CONTROL_HARDWARE_MODULE_ID, hw_module->id) != 0) {
+    ret = -EINVAL;
+  }
+  if (ret != 0) {
+    LOG(ERROR) << "Error loading boot_control HAL implementation.";
+    return false;
+  }
+
+  module_ = reinterpret_cast<boot_control_module_t*>(
+      const_cast<hw_module_t*>(hw_module));
+  module_->init(module_);
+
+  LOG(INFO) << "Loaded boot_control HAL "
+            << "'" << hw_module->name << "' "
+            << "version " << (hw_module->module_api_version >> 8) << "."
+            << (hw_module->module_api_version & 0xff) << " "
+            << "authored by '" << hw_module->author << "'.";
+  return true;
+}
+
+unsigned int BootControlRecovery::GetNumSlots() const {
+  return module_->getNumberSlots(module_);
+}
+
+BootControlInterface::Slot BootControlRecovery::GetCurrentSlot() const {
+  return module_->getCurrentSlot(module_);
+}
+
+bool BootControlRecovery::GetPartitionDevice(const string& partition_name,
+                                             Slot slot,
+                                             string* device) const {
+  // We can't use fs_mgr to look up |partition_name| because fstab
+  // doesn't list every slot partition (it uses the slotselect option
+  // to mask the suffix).
+  //
+  // We can however assume that there's an entry for the /misc mount
+  // point and use that to get the device file for the misc
+  // partition. This helps us locate the disk that |partition_name|
+  // resides on. From there we'll assume that a by-name scheme is used
+  // so we can just replace the trailing "misc" by the given
+  // |partition_name| and suffix corresponding to |slot|, e.g.
+  //
+  //   /dev/block/platform/soc.0/7824900.sdhci/by-name/misc ->
+  //   /dev/block/platform/soc.0/7824900.sdhci/by-name/boot_a
+  //
+  // If needed, it's possible to relax the by-name assumption in the
+  // future by trawling /sys/block looking for the appropriate sibling
+  // of misc and then finding an entry in /dev matching the sysfs
+  // entry.
+
+  base::FilePath misc_device;
+  if (!utils::DeviceForMountPoint("/misc", &misc_device))
+    return false;
+
+  if (!utils::IsSymlink(misc_device.value().c_str())) {
+    LOG(ERROR) << "Device file " << misc_device.value() << " for /misc "
+               << "is not a symlink.";
+    return false;
+  }
+
+  const char* suffix = module_->getSuffix(module_, slot);
+  if (suffix == nullptr) {
+    LOG(ERROR) << "boot_control impl returned no suffix for slot "
+               << SlotName(slot);
+    return false;
+  }
+
+  base::FilePath path = misc_device.DirName().Append(partition_name + suffix);
+  if (!base::PathExists(path)) {
+    LOG(ERROR) << "Device file " << path.value() << " does not exist.";
+    return false;
+  }
+
+  *device = path.value();
+  return true;
+}
+
+bool BootControlRecovery::IsSlotBootable(Slot slot) const {
+  int ret = module_->isSlotBootable(module_, slot);
+  if (ret < 0) {
+    LOG(ERROR) << "Unable to determine if slot " << SlotName(slot)
+               << " is bootable: " << strerror(-ret);
+    return false;
+  }
+  return ret == 1;
+}
+
+bool BootControlRecovery::MarkSlotUnbootable(Slot slot) {
+  int ret = module_->setSlotAsUnbootable(module_, slot);
+  if (ret < 0) {
+    LOG(ERROR) << "Unable to mark slot " << SlotName(slot)
+               << " as bootable: " << strerror(-ret);
+    return false;
+  }
+  return ret == 0;
+}
+
+bool BootControlRecovery::SetActiveBootSlot(Slot slot) {
+  int ret = module_->setActiveBootSlot(module_, slot);
+  if (ret < 0) {
+    LOG(ERROR) << "Unable to set the active slot to slot " << SlotName(slot)
+               << ": " << strerror(-ret);
+  }
+  return ret == 0;
+}
+
+bool BootControlRecovery::MarkBootSuccessfulAsync(
+    base::Callback<void(bool)> callback) {
+  int ret = module_->markBootSuccessful(module_);
+  if (ret < 0) {
+    LOG(ERROR) << "Unable to mark boot successful: " << strerror(-ret);
+  }
+  return brillo::MessageLoop::current()->PostTask(
+             FROM_HERE, base::Bind(callback, ret == 0)) !=
+         brillo::MessageLoop::kTaskIdNull;
+}
+
+}  // namespace chromeos_update_engine