// Copyright 2023 PingCAP, 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 "SharedLibrary.h"

#include <dlfcn.h>

#include <boost/core/noncopyable.hpp>
#include <string>

#include "Exception.h"

namespace DB
{
namespace ErrorCodes
{
extern const int CANNOT_DLOPEN;
extern const int CANNOT_DLSYM;
} // namespace ErrorCodes

SharedLibrary::SharedLibrary(const std::string & path)
{
    handle = dlopen(path.c_str(), RTLD_LAZY);
    if (!handle)
        throw Exception(std::string("Cannot dlopen: ") + dlerror(), ErrorCodes::CANNOT_DLOPEN);
}

SharedLibrary::~SharedLibrary()
{
    if (handle && dlclose(handle))
        std::terminate();
}

void * SharedLibrary::getImpl(const std::string & name, bool no_throw)
{
    dlerror();

    auto * res = dlsym(handle, name.c_str());

    if (char * error = dlerror())
    {
        if (no_throw)
            return nullptr;
        throw Exception(std::string("Cannot dlsym: ") + error, ErrorCodes::CANNOT_DLSYM);
    }

    return res;
}
} // namespace DB