Merge branch 'v0.23.x'

doc/mpdconf.example

@@ -79,7 +79,7 @@
 # This setting sets the address for the daemon to listen on. Careful attention
 # should be paid if this is assigned to anything other than the default, any.
 # This setting can deny access to control of the daemon. Not effective if
-# systemd socket activiation is in use.
+# systemd socket activation is in use.
 #
 # For network
 #bind_to_address		"any"
@@ -185,7 +185,7 @@
 #       cache_directory "~/.local/share/mpd/cache"
 #}
 #
-# An example of database config for a sattelite setup
+# An example of database config for a satellite setup
 #
 #music_directory "nfs://fileserver.local/srv/mp3"
 #database {

doc/protocol.rst

@@ -479,7 +479,7 @@ Querying :program:`MPD`'s status
       current song in seconds, but with higher resolution.
     - ``duration`` [#since_0_20]_: Duration of the current song in seconds.
     - ``bitrate``: instantaneous bitrate in kbps
-    - ``xfade``: ``crossfade`` in seconds
+    - ``xfade``: ``crossfade`` in seconds (see :ref:`crossfading`)
     - ``mixrampdb``: ``mixramp`` threshold in dB
     - ``mixrampdelay``: ``mixrampdelay`` in seconds
     - ``audio``: The format emitted by the decoder plugin during
@@ -519,17 +519,19 @@ Playback options
 .. _command_crossfade:
 
 :command:`crossfade {SECONDS}`
-    Sets crossfading between songs.
+    Sets crossfading between songs.  See :ref:`crossfading`.
 
 .. _command_mixrampdb:
 
 :command:`mixrampdb {deciBels}`
-    Sets the threshold at which songs will be overlapped. Like crossfading but doesn't fade the track volume, just overlaps. The songs need to have MixRamp tags added by an external tool. 0dB is the normalized maximum volume so use negative values, I prefer -17dB. In the absence of mixramp tags crossfading will be used. See http://sourceforge.net/projects/mixramp
+    Sets the threshold at which songs will be overlapped.
+    See :ref:`mixramp`.
 
 .. _command_mixrampdelay:
 
 :command:`mixrampdelay {SECONDS}`
     Additional time subtracted from the overlap calculated by mixrampdb. A value of "nan" disables MixRamp overlapping and falls back to crossfading.
+    See :ref:`mixramp`.
 
 .. _command_random:
 

doc/user.rst

@@ -622,6 +622,51 @@ enabled by setting ``volume_normalization`` to ``yes``.  It supports
 16 bit PCM only.
 
 
+.. _crossfading:
+
+Cross-Fading
+------------
+
+If ``crossfade`` is set to a positive number, then adjacent songs are
+cross-faded by this number of seconds.  This is a run-time setting
+:ref:`which can be controlled by clients <command_crossfade>`,
+e.g. with :program:`mpc`::
+
+  mpc crossfade 10
+  mpc crossfade 0
+
+Zero means cross-fading is disabled.
+
+Cross-fading is only possible if both songs have the same audio
+format.  At the cost of quality loss and higher CPU usage, you can
+make sure this is always given by configuring
+:ref:`audio_output_format`.
+
+.. _mixramp:
+
+MixRamp
+^^^^^^^
+
+MixRamp tags describe the loudness levels at start and end of a song
+and can be used by MPD to find the best time to begin cross-fading.
+MPD enables MixRamp if:
+
+- Cross-fade is enabled
+- :ref:`mixrampdelay <command_mixrampdelay>` is set to a positive
+  value, e.g.::
+    mpc mixrampdelay 1
+- :ref:`mixrampdb <command_mixrampdb>` is set to a reasonable value,
+  e.g.::
+    mpc mixrampdb -17
+- both songs have MixRamp tags
+- both songs have the same audio format (or :ref:`audio_output_format`
+  is configured)
+
+The `MixRamp <http://sourceforge.net/projects/mixramp>`__ tool can be
+used to add MixRamp tags to your song files.
+
+
+
 Client Connections
 ------------------
 

src/LocateUri.cxx

@@ -48,15 +48,14 @@ LocateFileUri(const char *uri, const Client *client
 			/* this path was relative to the music
 			   directory */
 			// TODO: don't use suffix.data() (ok for now because we know it's null-terminated)
-			return LocatedUri(LocatedUri::Type::RELATIVE,
+			return {LocatedUri::Type::RELATIVE, suffix.data()};
-					  suffix.data());
 	}
 #endif
 
 	if (client != nullptr)
 		client->AllowFile(path);
 
-	return LocatedUri(LocatedUri::Type::PATH, uri, std::move(path));
+	return {LocatedUri::Type::PATH, uri, std::move(path)};
 }
 
 static LocatedUri
@@ -90,8 +89,7 @@ LocateAbsoluteUri(UriPluginKind kind, const char *uri
 		const auto suffix = storage->MapToRelativeUTF8(uri);
 		if (suffix.data() != nullptr)
 			// TODO: don't use suffix.data() (ok for now because we know it's null-terminated)
-			return LocatedUri(LocatedUri::Type::RELATIVE,
+			return {LocatedUri::Type::RELATIVE, suffix.data()};
-					  suffix.data());
 	}
 
 	if (kind == UriPluginKind::STORAGE &&
@@ -99,7 +97,7 @@ LocateAbsoluteUri(UriPluginKind kind, const char *uri
 		throw std::invalid_argument("Unsupported URI scheme");
 #endif
 
-	return LocatedUri(LocatedUri::Type::ABSOLUTE, uri);
+	return {LocatedUri::Type::ABSOLUTE, uri};
 }
 
 LocatedUri

src/lib/curl/Escape.cxx

@@ -60,7 +60,7 @@ CurlUnescape(CURL *curl, StringView src) noexcept
 	int outlength;
 	CurlString tmp(curl_easy_unescape(curl, src.data, src.size,
 					  &outlength));
-	return std::string(tmp.c_str(), outlength);
+	return {tmp.c_str(), size_t(outlength)};
 }
 
 std::string

src/pcm/LibsamplerateResampler.cxx

@@ -140,8 +140,7 @@ LibsampleratePcmResampler::Resample2(ConstBuffer<float> src)
 		throw FormatRuntimeError("libsamplerate has failed: %s",
 					 src_strerror(result));
 
-	return ConstBuffer<float>(data.data_out,
+	return {data.data_out, size_t(data.output_frames_gen * channels)};
-				  data.output_frames_gen * channels);
 }
 
 ConstBuffer<void>