add sound reader code

stepmania/src/RageSoundReader.h

@@ -0,0 +1,25 @@
+#ifndef RAGE_SOUND_READER_H
+#define RAGE_SOUND_READER_H
+
+/* A sound reader is a source for a RageSound.  It's usually just a convenience
+ * wrapper around SDL_Sound. */
+class SoundReader {
+	mutable string error;
+
+protected:
+	void SetError(string e) const { error = e; }
+
+public:
+	virtual bool Open(CString filename) = 0;
+	virtual int GetLength() const = 0; /* ms */
+	virtual int GetLength_Fast() const { return GetLength(); } /* ms */
+	virtual int SetPosition_Accurate(int ms) = 0;
+	virtual int SetPosition_Fast(int ms) { return SetPosition_Accurate(ms); }
+	virtual int Read(char *buf, unsigned len) = 0;
+	virtual ~SoundReader() { }
+
+	bool Error() const { return !error.empty(); }
+	string GetError() const { return error; }
+};
+
+#endif

stepmania/src/RageSoundReader_SDL_Sound.cpp

@@ -0,0 +1,144 @@
+#include "stdafx.h"
+
+/*
+ * Known problems:
+ * I hear a click in one speaker at the beginning of some MP3s.  This is probably
+ * something wrong with my SDL_sound MAD wrapper ...
+ */
+
+#ifdef _DEBUG
+#pragma comment(lib, "SDL_sound-1.0.0/lib/sdl_sound_static_d.lib")
+#else
+#pragma comment(lib, "SDL_sound-1.0.0/lib/sdl_sound_static.lib")
+#endif
+
+#include "RageSoundReader_SDL_Sound.h"
+
+const int channels = 2;
+const int samplesize = 2 * channels; /* 16-bit */
+const int samplerate = 44100;
+
+/* The amount of data to read from SDL_sound at once. */
+const int read_block_size = 1024;
+
+bool SoundReader_SDL_Sound::Open(CString filename)
+{
+	inbuf = NULL;
+	avail = 0;
+
+	Sound_AudioInfo sound_desired;
+	sound_desired.channels = channels;
+	sound_desired.format = AUDIO_S16SYS;
+	sound_desired.rate = samplerate;
+
+    Sample = Sound_NewSampleFromFile(filename.GetString(),
+                    &sound_desired, read_block_size);
+
+	if(Sample)
+		return true;
+	
+	SetError(Sound_GetError());
+	return false;
+}
+
+int SoundReader_SDL_Sound::GetLength() const
+{
+	int len = Sound_Length(Sample);
+	if(len == -1 && Sample->flags & SOUND_SAMPLEFLAG_EAGAIN) {
+		/* This indicates the length check will take a little while; call
+		 * it again to confirm. */
+		len = Sound_Length(Sample);
+	}
+
+	if(len < 0)
+	{
+		SetError(Sound_GetError());
+		return -1;
+	}
+
+	return len;
+}
+
+int SoundReader_SDL_Sound::GetLength_Fast() const
+{
+	int ret = Sound_Length(Sample);
+
+	Sound_Rewind(Sample);
+	return ret;
+}
+
+int SoundReader_SDL_Sound::SetPosition(int ms, bool accurate)
+{
+	if(ms == 0)
+	{
+		Sound_Rewind(Sample);
+		return 0;
+	}
+
+	int ret;
+	if(accurate)
+		ret = Sound_AccurateSeek(Sample, ms);
+	else
+		ret = Sound_FastSeek(Sample, ms);
+
+	if(Sample->flags & SOUND_SAMPLEFLAG_ERROR)
+	{
+		SetError(Sound_GetError());
+		return -1;
+	}
+
+	/* If the seek function returned false but didn't set error, it's a
+	 * recoverable error.  We probably seeked past end of file. */
+	if(!ret)
+	{
+		/* Past EOF.  Rewind. */
+		Sound_Rewind(Sample);
+		return 0;
+	}
+
+
+	return ms;
+}
+
+int SoundReader_SDL_Sound::Read(char *buf, unsigned len)
+{
+	int bytes_read = 0;
+	while(len)
+	{
+		if(!avail)
+		{
+			/* Don't read at all if we've already hit EOF (it'll whine). */
+			if(Sample->flags & SOUND_SAMPLEFLAG_EOF)
+				return bytes_read; /* EOF */
+
+			int cnt = Sound_Decode(Sample);
+
+			if(Sample->flags & SOUND_SAMPLEFLAG_EOF)
+				return bytes_read; /* EOF */
+
+			if(Sample->flags & SOUND_SAMPLEFLAG_ERROR)
+			{
+				SetError(Sound_GetError());
+				return -1;
+			}
+
+			avail = cnt;
+			inbuf = (const char *) Sample->buffer;
+		}
+
+		unsigned size = min(avail, len);
+		memcpy(buf, inbuf, size);
+		buf += size;
+		len -= size;
+		inbuf += size;
+		avail -= size;
+		bytes_read += size;
+	}
+
+	return bytes_read;
+}
+
+SoundReader_SDL_Sound::~SoundReader_SDL_Sound()
+{
+	Sound_FreeSample(Sample);
+}

stepmania/src/RageSoundReader_SDL_Sound.h

@@ -0,0 +1,23 @@
+#ifndef RAGE_SOUND_READER_SDL_SOUND
+#define RAGE_SOUND_READER_SDL_SOUND
+
+#include "RageSoundReader.h"
+#include "SDL_sound-1.0.0/SDL_sound.h"
+
+class SoundReader_SDL_Sound: public SoundReader {
+	Sound_Sample *Sample;
+	const char *inbuf;
+	unsigned avail;
+	int SetPosition(int ms, bool accurate);
+
+public:
+	bool Open(CString filename);
+	int GetLength() const;
+	int GetLength_Fast() const;
+	int SetPosition_Accurate(int ms)  { return SetPosition(ms, true); }
+	int SetPosition_Fast(int ms) { return SetPosition(ms, false); }
+	int Read(char *buf, unsigned len);
+	~SoundReader_SDL_Sound();
+};
+
+#endif