prod/native/extension/code/Hooking.h

/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch B.V. licenses this file to you 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.
 */

#pragma once

#include <Zend/zend_execute.h>
#include <Zend/zend_types.h>

namespace elasticapm::php {

class Hooking {
public:
    using zend_execute_internal_t = void (*)(zend_execute_data *execute_data, zval *return_value);
    using zend_interrupt_function_t = void (*)(zend_execute_data *execute_data);
    using zend_compile_file_t = zend_op_array *(*)(zend_file_handle *file_handle, int type);

    static Hooking &getInstance() {
        static Hooking instance;
        return instance;
    }

    void fetchOriginalHooks() {
        original_execute_internal_ = zend_execute_internal;
        original_zend_interrupt_function_ = zend_interrupt_function;
        original_zend_compile_file_ = zend_compile_file;
    }

    void restoreOriginalHooks() {
        zend_execute_internal = original_execute_internal_;
        zend_interrupt_function = original_zend_interrupt_function_;
        zend_compile_file = original_zend_compile_file_;
    }

    zend_execute_internal_t getOriginalExecuteInternal() {
        return original_execute_internal_;
    }

    zend_interrupt_function_t getOriginalZendInterruptFunction() {
        return original_zend_interrupt_function_;
    }

    zend_compile_file_t getOriginalZendCompileFile() {
        return original_zend_compile_file_;
    }

    void replaceHooks(bool enableInferredSpansHooks, bool enableDepenecyAutoloaderGuard);

private:
    Hooking(Hooking const &) = delete;
    void operator=(Hooking const &) = delete;
    Hooking() = default;

    zend_execute_internal_t original_execute_internal_ = nullptr;
    zend_interrupt_function_t original_zend_interrupt_function_ = nullptr;
    zend_compile_file_t original_zend_compile_file_ = nullptr;
};

} // namespace elasticapm::php