cpp/util/hooks.cpp (30 lines of code) (raw):
/**
* Copyright 2004-present, Facebook, Inc.
*
* 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 <profilo/util/hooks.h>
#include <dlfcn.h>
#include <stdexcept>
#include <string>
#include <unordered_set>
#include <utility>
#include <vector>
#include <linker/sharedlibs.h>
namespace facebook {
namespace profilo {
namespace hooks {
// Arguments:
// functionHooks: vector of pairs {"function", ptr_to_function}
// eg: {{"write", writeHook}, {"read", readHook}},
// allowHookingCb: callback function to give a client control whether to hook a
// particular library.
// It is mainly used for 2 reasons:
// 1) Allow the client to blacklist libraries.
// 2) Avoid hooking the same library twice.
// data: Optional custom data pointer which will be passed to allowHookingCb as
// a parameter.
void hookLoadedLibs(
std::vector<plt_hook_spec>& functionHooks,
AllowHookingLibCallback allowHookingCb,
void* data) {
int ret = hook_all_libs(
functionHooks.data(), functionHooks.size(), allowHookingCb, data);
if (ret) {
throw std::runtime_error("Could not hook libraries");
}
}
void unhookLoadedLibs(std::vector<plt_hook_spec>& functionHooks) {
int ret = unhook_all_libs(functionHooks.data(), functionHooks.size());
if (ret) {
throw std::runtime_error("Could not unhook libraries");
}
}
} // namespace hooks
} // namespace profilo
} // namespace facebook