aosp12/bionic/tests/dlfcn_symlink_support.cpp

79 lines
2.5 KiB
C++

/*
* Copyright (C) 2016 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 "dlfcn_symlink_support.h"
#include <gtest/gtest.h>
#include <dlfcn.h>
#include <libgen.h>
#include <link.h>
#include <unistd.h>
#include <android-base/strings.h>
#include <algorithm>
#include <string>
#include <vector>
static const constexpr char* source_file_name = "libdlext_test.so";
static const constexpr char* symlink_name_prefix = "libdlext_test_";
static int dl_callback(struct dl_phdr_info *info, size_t /* size */, void *data) {
// The case when path is not absolute and is equal to source_file_name
// is disregarded intentionally since in bionic dlpi_name should always
// be realpath to a shared object.
const std::string suffix = std::string("/") + source_file_name;
// TODO (dimitry): remove this check once fake libdl.so is gone
if (info->dlpi_name == nullptr) {
// This is linker imposing as libdl.so - skip it
return 0;
}
if (android::base::EndsWith(info->dlpi_name, suffix)) {
std::string* path = reinterpret_cast<std::string*>(data);
*path = info->dlpi_name;
return 1; // found
}
return 0;
}
void create_dlfcn_test_symlink(const char* suffix, std::string* result) {
void* handle = dlopen(source_file_name, RTLD_NOW);
std::string source_file_path;
ASSERT_TRUE(handle != nullptr) << dlerror();
ASSERT_TRUE(dl_iterate_phdr(dl_callback, &source_file_path) == 1)
<< "dl_phdr_info for \"" << source_file_name << "\" was not found.";
dlclose(handle);
std::vector<char> buf;
std::copy(source_file_path.begin(), source_file_path.end(), std::back_inserter(buf));
buf.push_back('\0');
std::string path_dir = dirname(&buf[0]);
std::string link_path = path_dir + "/" + symlink_name_prefix + suffix + ".so";
ASSERT_TRUE(symlink(source_file_path.c_str(), link_path.c_str()) == 0) << strerror(errno);
*result = link_path;
}
void remove_dlfcn_test_symlink(const std::string& path) {
ASSERT_TRUE(unlink(path.c_str()) == 0) << strerror(errno);
}