Nagram/TMessagesProj/jni/voip/webrtc/base/android/bundle_utils.cc
2020-09-30 16:48:47 +03:00

105 lines
3.5 KiB
C++

// Copyright 2019 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/android/bundle_utils.h"
#include <android/dlext.h>
#include <dlfcn.h>
#include "base/android/jni_android.h"
#include "base/android/jni_string.h"
#include "base/base_jni_headers/BundleUtils_jni.h"
#include "base/files/file_path.h"
#include "base/logging.h"
// These symbols are added by the lld linker when creating a partitioned shared
// library. The symbols live in the base library, and are used to properly load
// the other partitions (feature libraries) when needed.
struct PartitionIndexEntry {
int32_t name_relptr;
int32_t addr_relptr;
uint32_t size;
};
static_assert(sizeof(PartitionIndexEntry) == 12U,
"Unexpected PartitionIndexEntry size");
// Marked as weak_import because these symbols are lld-specific. The method that
// uses them will only be invoked in builds that have lld-generated partitions.
extern PartitionIndexEntry __part_index_begin[] __attribute__((weak_import));
extern PartitionIndexEntry __part_index_end[] __attribute__((weak_import));
extern "C" {
// Marked as weak_import because this symbol is either supplied by the system
// (on Android N+), or by Crazy Linker (Android M and prior).
extern void* android_dlopen_ext(const char* __filename,
int __flags,
const android_dlextinfo* __info)
__attribute__((weak_import));
} // extern "C"
namespace base {
namespace android {
namespace {
const void* ReadRelPtr(const int32_t* relptr) {
return reinterpret_cast<const char*>(relptr) + *relptr;
}
} // namespace
// static
std::string BundleUtils::ResolveLibraryPath(const std::string& library_name) {
JNIEnv* env = AttachCurrentThread();
ScopedJavaLocalRef<jstring> java_path = Java_BundleUtils_getNativeLibraryPath(
env, base::android::ConvertUTF8ToJavaString(env, library_name));
// TODO(https://crbug.com/1019853): Remove this tolerance.
if (!java_path) {
return std::string();
}
return base::android::ConvertJavaStringToUTF8(env, java_path);
}
// static
bool BundleUtils::IsBundle() {
return Java_BundleUtils_isBundleForNative(
base::android::AttachCurrentThread());
}
// static
void* BundleUtils::DlOpenModuleLibraryPartition(const std::string& library_name,
const std::string& partition) {
// TODO(https://crbug.com/1019853): Remove this tolerance.
std::string library_path = ResolveLibraryPath(library_name);
if (library_path.empty()) {
return nullptr;
}
// Linear search is required here because the partition descriptors are not
// ordered. If a large number of partitions come into existence, lld could be
// modified to sort the partitions.
DCHECK(__part_index_begin != nullptr);
DCHECK(__part_index_end != nullptr);
for (const PartitionIndexEntry* part = __part_index_begin;
part != __part_index_end; ++part) {
std::string name(
reinterpret_cast<const char*>(ReadRelPtr(&part->name_relptr)));
if (name == partition) {
android_dlextinfo info = {};
info.flags = ANDROID_DLEXT_RESERVED_ADDRESS;
info.reserved_addr = const_cast<void*>(ReadRelPtr(&part->addr_relptr));
info.reserved_size = part->size;
DCHECK(android_dlopen_ext != nullptr);
return android_dlopen_ext(library_path.c_str(), RTLD_LOCAL, &info);
}
}
NOTREACHED();
return nullptr;
}
} // namespace android
} // namespace base