AudioFormat: replace struct audio_format_string with class StringBuffer, return it

6 files changed, 27 insertions, 41 deletions

diff --git a/src/AudioFormat.cxx b/src/AudioFormat.cxx
index a374bc02e..c3ebb2e6f 100644
--- a/src/AudioFormat.cxx
+++ b/src/AudioFormat.cxx
@@ -18,6 +18,7 @@
  */
 
 #include "AudioFormat.hxx"
+#include "util/StringBuffer.hxx"
 
 #include <assert.h>
 #include <stdio.h>
@@ -40,15 +41,13 @@ AudioFormat::ApplyMask(AudioFormat mask)
 	assert(IsValid());
 }
 
-const char *
-audio_format_to_string(const AudioFormat af,
-		       struct audio_format_string *s)
+StringBuffer<24>
+ToString(const AudioFormat af)
 {
-	assert(s != nullptr);
-
-	snprintf(s->buffer, sizeof(s->buffer), "%u:%s:%u",
+	StringBuffer<24> buffer;
+	snprintf(buffer.data(), buffer.capacity(), "%u:%s:%u",
 		 af.sample_rate, sample_format_to_string(af.format),
 		 af.channels);
 
-	return s->buffer;
+	return buffer;
 }
diff --git a/src/AudioFormat.hxx b/src/AudioFormat.hxx
index f39dc21e7..09fe99405 100644
--- a/src/AudioFormat.hxx
+++ b/src/AudioFormat.hxx
@@ -23,8 +23,11 @@
 #include "pcm/SampleFormat.hxx"
 #include "Compiler.h"
 
-#include <stdint.h>
 #include <assert.h>
+#include <stdint.h>
+#include <stddef.h>
+
+template<size_t CAPACITY> class StringBuffer;
 
 static constexpr unsigned MAX_CHANNELS = 8;
 
@@ -148,13 +151,6 @@ struct AudioFormat {
 };
 
 /**
- * Buffer for audio_format_string().
- */
-struct audio_format_string {
-	char buffer[24];
-};
-
-/**
  * Checks whether the sample rate is valid.
  *
  * @param sample_rate the sample rate in Hz
@@ -226,9 +222,8 @@ AudioFormat::GetTimeToSize() const
  * @param s a buffer to print into
  * @return the string, or nullptr if the #AudioFormat object is invalid
  */
-gcc_pure gcc_malloc
-const char *
-audio_format_to_string(AudioFormat af,
-		       struct audio_format_string *s);
+gcc_const
+StringBuffer<24>
+ToString(AudioFormat af);
 
 #endif
diff --git a/src/command/PlayerCommands.cxx b/src/command/PlayerCommands.cxx
index f843bc5ff..a48890028 100644
--- a/src/command/PlayerCommands.cxx
+++ b/src/command/PlayerCommands.cxx
@@ -30,6 +30,7 @@
 #include "Instance.hxx"
 #include "Idle.hxx"
 #include "AudioFormat.hxx"
+#include "util/StringBuffer.hxx"
 #include "util/ScopeExit.hxx"
 #include "util/Exception.hxx"
 
@@ -171,13 +172,9 @@ handle_status(Client &client, gcc_unused Request args, Response &r)
 			r.Format("duration: %1.3f\n",
 				 player_status.total_time.ToDoubleS());
 
-		if (player_status.audio_format.IsDefined()) {
-			struct audio_format_string af_string;
-
+		if (player_status.audio_format.IsDefined())
 			r.Format(COMMAND_STATUS_AUDIO ": %s\n",
-				 audio_format_to_string(player_status.audio_format,
-							&af_string));
-		}
+				 ToString(player_status.audio_format).c_str());
 	}
 
 #ifdef ENABLE_DATABASE
diff --git a/src/decoder/Bridge.cxx b/src/decoder/Bridge.cxx
index 0df3eb39e..201e6a1aa 100644
--- a/src/decoder/Bridge.cxx
+++ b/src/decoder/Bridge.cxx
@@ -32,6 +32,7 @@
 #include "Log.hxx"
 #include "input/InputStream.hxx"
 #include "util/ConstBuffer.hxx"
+#include "util/StringBuffer.hxx"
 
 #include <assert.h>
 #include <string.h>
@@ -246,15 +247,13 @@ void
 DecoderBridge::Ready(const AudioFormat audio_format,
 		     bool seekable, SignedSongTime duration)
 {
-	struct audio_format_string af_string;
-
 	assert(convert == nullptr);
 	assert(stream_tag == nullptr);
 	assert(decoder_tag == nullptr);
 	assert(!seeking);
 
 	FormatDebug(decoder_domain, "audio_format=%s, seekable=%s",
-		    audio_format_to_string(audio_format, &af_string),
+		    ToString(audio_format).c_str(),
 		    seekable ? "true" : "false");
 
 	{
@@ -264,8 +263,7 @@ DecoderBridge::Ready(const AudioFormat audio_format,
 
 	if (dc.in_audio_format != dc.out_audio_format) {
 		FormatDebug(decoder_domain, "converting to %s",
-			    audio_format_to_string(dc.out_audio_format,
-						   &af_string));
+			    ToString(dc.out_audio_format).c_str());
 
 		convert = new PcmConvert();
 
diff --git a/src/filter/plugins/ChainFilterPlugin.cxx b/src/filter/plugins/ChainFilterPlugin.cxx
index db62c70b1..d7c3525ee 100644
--- a/src/filter/plugins/ChainFilterPlugin.cxx
+++ b/src/filter/plugins/ChainFilterPlugin.cxx
@@ -24,6 +24,7 @@
 #include "filter/FilterRegistry.hxx"
 #include "AudioFormat.hxx"
 #include "util/ConstBuffer.hxx"
+#include "util/StringBuffer.hxx"
 #include "util/RuntimeError.hxx"
 
 #include <memory>
@@ -108,10 +109,9 @@ PreparedChainFilter::Child::Open(const AudioFormat &prev_audio_format)
 	if (conv_audio_format != prev_audio_format) {
 		delete new_filter;
 
-		struct audio_format_string s;
 		throw FormatRuntimeError("Audio format not supported by filter '%s': %s",
 					 name,
-					 audio_format_to_string(prev_audio_format, &s));
+					 ToString(prev_audio_format).c_str());
 	}
 
 	return new_filter;
diff --git a/src/output/OutputThread.cxx b/src/output/OutputThread.cxx
index 047dbe0c0..c2ee2ccfc 100644
--- a/src/output/OutputThread.cxx
+++ b/src/output/OutputThread.cxx
@@ -35,6 +35,7 @@
 #include "thread/Slack.hxx"
 #include "thread/Name.hxx"
 #include "util/ConstBuffer.hxx"
+#include "util/StringBuffer.hxx"
 #include "util/ScopeExit.hxx"
 #include "util/RuntimeError.hxx"
 #include "Log.hxx"
@@ -154,14 +155,11 @@ AudioOutput::Open()
 		}
 	}
 
-	if (f != source.GetInputAudioFormat() || f != out_audio_format) {
-		struct audio_format_string afs1, afs2, afs3;
+	if (f != source.GetInputAudioFormat() || f != out_audio_format)
 		FormatDebug(output_domain, "converting in=%s -> f=%s -> out=%s",
-			    audio_format_to_string(source.GetInputAudioFormat(),
-						   &afs1),
-			    audio_format_to_string(f, &afs2),
-			    audio_format_to_string(out_audio_format, &afs3));
-	}
+			    ToString(source.GetInputAudioFormat()).c_str(),
+			    ToString(f).c_str(),
+			    ToString(out_audio_format).c_str());
 }
 
 void
@@ -176,11 +174,10 @@ AudioOutput::OpenOutputAndConvert(AudioFormat desired_audio_format)
 							  name, plugin.name));
 	}
 
-	struct audio_format_string af_string;
 	FormatDebug(output_domain,
 		    "opened plugin=%s name=\"%s\" audio_format=%s",
 		    plugin.name, name,
-		    audio_format_to_string(out_audio_format, &af_string));
+		    ToString(out_audio_format).c_str());
 
 	try {
 		convert_filter_set(convert_filter.Get(), out_audio_format);