mpd/src/lib/curl/Multi.hxx
2021-03-29 20:19:21 +02:00

132 lines
3.4 KiB
C++

/*
* Copyright 2016-2020 Max Kellermann <max.kellermann@gmail.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef CURL_MULTI_HXX
#define CURL_MULTI_HXX
#include <curl/curl.h>
#include <chrono>
#include <utility>
#include <stdexcept>
#include <cstddef>
/**
* An OO wrapper for a "CURLM*" (a libCURL "multi" handle).
*/
class CurlMulti {
CURLM *handle = nullptr;
public:
/**
* Allocate a new CURLM*.
*
* Throws on error.
*/
CurlMulti()
:handle(curl_multi_init())
{
if (handle == nullptr)
throw std::runtime_error("curl_multi_init() failed");
}
/**
* Create an empty instance.
*/
CurlMulti(std::nullptr_t) noexcept:handle(nullptr) {}
CurlMulti(CurlMulti &&src) noexcept
:handle(std::exchange(src.handle, nullptr)) {}
~CurlMulti() noexcept {
if (handle != nullptr)
curl_multi_cleanup(handle);
}
CurlMulti &operator=(CurlMulti &&src) noexcept {
std::swap(handle, src.handle);
return *this;
}
operator bool() const noexcept {
return handle != nullptr;
}
CURLM *Get() noexcept {
return handle;
}
template<typename T>
void SetOption(CURLMoption option, T value) {
auto code = curl_multi_setopt(handle, option, value);
if (code != CURLM_OK)
throw std::runtime_error(curl_multi_strerror(code));
}
void Add(CURL *easy) {
auto code = curl_multi_add_handle(handle, easy);
if (code != CURLM_OK)
throw std::runtime_error(curl_multi_strerror(code));
}
void Remove(CURL *easy) {
auto code = curl_multi_remove_handle(handle, easy);
if (code != CURLM_OK)
throw std::runtime_error(curl_multi_strerror(code));
}
CURLMsg *InfoRead() {
int msgs_in_queue;
return curl_multi_info_read(handle, &msgs_in_queue);
}
unsigned Perform() {
int running_handles;
auto code = curl_multi_perform(handle, &running_handles);
if (code != CURLM_OK)
throw std::runtime_error(curl_multi_strerror(code));
return running_handles;
}
unsigned Wait(int timeout=-1) {
int numfds;
auto code = curl_multi_wait(handle, nullptr, 0, timeout,
&numfds);
if (code != CURLM_OK)
throw std::runtime_error(curl_multi_strerror(code));
return numfds;
}
unsigned Wait(std::chrono::milliseconds timeout) {
return Wait(timeout.count());
}
};
#endif