input/cache: first draft of the file cache

src/decoder/Bridge.cxx

@@ -31,6 +31,8 @@
 #include "Log.hxx"
 #include "input/InputStream.hxx"
 #include "input/LocalOpen.hxx"
+#include "input/cache/Manager.hxx"
+#include "input/cache/Stream.hxx"
 #include "fs/Path.hxx"
 #include "util/ConstBuffer.hxx"
 #include "util/StringBuffer.hxx"
@@ -52,8 +54,18 @@ DecoderBridge::~DecoderBridge() noexcept
 }
 
 InputStreamPtr
-DecoderBridge::OpenLocal(Path path_fs)
+DecoderBridge::OpenLocal(Path path_fs, const char *uri_utf8)
 {
+	if (dc.input_cache != nullptr) {
+		auto lease = dc.input_cache->Get(uri_utf8, true);
+		if (lease) {
+			auto is = std::make_unique<CacheInputStream>(std::move(lease),
+								     dc.mutex);
+			is->SetHandler(&dc);
+			return is;
+		}
+	}
+
 	return OpenLocalInputStream(path_fs, dc.mutex);
 }
 

src/decoder/Bridge.hxx

@@ -157,7 +157,7 @@ public:
 	/**
 	 * Open a local file.
 	 */
-	InputStreamPtr OpenLocal(Path path_fs);
+	InputStreamPtr OpenLocal(Path path_fs, const char *uri_utf8);
 
 	/* virtual methods from DecoderClient */
 	void Ready(AudioFormat audio_format,

src/decoder/Control.cxx

@@ -26,9 +26,11 @@
 #include <assert.h>
 
 DecoderControl::DecoderControl(Mutex &_mutex, Cond &_client_cond,
+			       InputCacheManager *_input_cache,
 			       const AudioFormat _configured_audio_format,
 			       const ReplayGainConfig &_replay_gain_config) noexcept
 	:thread(BIND_THIS_METHOD(RunThread)),
+	 input_cache(_input_cache),
 	 mutex(_mutex), client_cond(_client_cond),
 	 configured_audio_format(_configured_audio_format),
 	 replay_gain_config(_replay_gain_config) {}

src/decoder/Control.hxx

@@ -46,6 +46,7 @@
 class DetachedSong;
 class MusicBuffer;
 class MusicPipe;
+class InputCacheManager;
 
 enum class DecoderState : uint8_t {
 	STOP = 0,
@@ -68,6 +69,8 @@ class DecoderControl final : public InputStreamHandler {
 	Thread thread;
 
 public:
+	InputCacheManager *const input_cache;
+
 	/**
 	 * This lock protects #state and #command.
 	 *
@@ -181,6 +184,7 @@ public:
 	 * @param _client_cond see #client_cond
 	 */
 	DecoderControl(Mutex &_mutex, Cond &_client_cond,
+		       InputCacheManager *_input_cache,
 		       const AudioFormat _configured_audio_format,
 		       const ReplayGainConfig &_replay_gain_config) noexcept;
 	~DecoderControl() noexcept;

src/decoder/Thread.cxx

@@ -346,7 +346,7 @@ decoder_run_file(DecoderBridge &bridge, const char *uri_utf8, Path path_fs)
 	InputStreamPtr input_stream;
 
 	try {
-		input_stream = bridge.OpenLocal(path_fs);
+		input_stream = bridge.OpenLocal(path_fs, uri_utf8);
 	} catch (const std::system_error &e) {
 		if (IsPathNotFound(e) &&
 		    /* ENOTDIR means this may be a path inside a