mpd/src/input/InputPlugin.hxx
2023-03-06 14:59:48 +01:00

94 lines
2.1 KiB
C++

// SPDX-License-Identifier: GPL-2.0-or-later
// Copyright The Music Player Daemon Project
#ifndef MPD_INPUT_PLUGIN_HXX
#define MPD_INPUT_PLUGIN_HXX
#include "Ptr.hxx"
#include "thread/Mutex.hxx"
#include <cassert>
#include <set>
#include <string>
struct ConfigBlock;
class EventLoop;
class RemoteTagScanner;
class RemoteTagHandler;
struct InputPlugin {
const char *name;
/**
* A nullptr-terminated list of URI prefixes handled by this
* plugin. This is usually a string in the form "scheme://".
*/
const char *const*prefixes;
/**
* Global initialization. This method is called when MPD starts.
*
* Throws #PluginUnavailable if the plugin is not available
* and shall be disabled.
*
* Throws std::runtime_error on (fatal) error.
*/
void (*init)(EventLoop &event_loop, const ConfigBlock &block);
/**
* Global deinitialization. Called once before MPD shuts
* down (only if init() has returned true).
*/
void (*finish)() noexcept;
/**
* Attempt to open the given URI. Returns nullptr if the
* plugin does not support this URI.
*
* Throws std::runtime_error on error.
*/
InputStreamPtr (*open)(const char *uri, Mutex &mutex);
/**
* return a set of supported protocols
*/
std::set<std::string> (*protocols)() noexcept;
/**
* Prepare a #RemoteTagScanner. The operation must be started
* using RemoteTagScanner::Start(). Returns nullptr if the
* plugin does not support this URI.
*
* Throws on error.
*
* @return nullptr if the given URI is not supported.
*/
std::unique_ptr<RemoteTagScanner> (*scan_tags)(const char *uri,
RemoteTagHandler &handler) = nullptr;
[[gnu::pure]]
bool SupportsUri(const char *uri) const noexcept;
template<typename F>
void ForeachSupportedUri(F lambda) const noexcept {
assert(prefixes || protocols);
if (prefixes != nullptr) {
for (auto schema = prefixes; *schema != nullptr; ++schema) {
lambda(*schema);
}
}
if (protocols != nullptr) {
for (auto schema : protocols()) {
lambda(schema.c_str());
}
}
}
};
[[gnu::pure]]
bool
protocol_is_whitelisted(const char *proto) noexcept;
#endif