added support for async playback to Unix implementation of wxSound, implemented SDL backend for playback if OSS is not available, fixed OSS to work on non-Linux Unices

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@25455 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/unix/sound.h

@@ -0,0 +1,136 @@
+/////////////////////////////////////////////////////////////////////////////
+// Name:        wave.h
+// Purpose:     wxSound class
+// Author:      Julian Smart, Vaclav Slavik
+// Modified by:
+// Created:     25/10/98
+// RCS-ID:      $Id$
+// Copyright:   (c) Julian Smart, Vaclav Slavik
+// Licence:   	wxWindows licence
+/////////////////////////////////////////////////////////////////////////////
+
+#ifndef _WX_SOUND_H_
+#define _WX_SOUND_H_
+
+#include "wx/defs.h"
+
+#if wxUSE_WAVE
+
+#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
+#pragma interface "sound.h"
+#endif
+
+#include "wx/object.h"
+
+// ----------------------------------------------------------------------------
+// wxSound: simple audio playback class
+// ----------------------------------------------------------------------------
+
+class wxSoundBackend;
+class wxSound;
+class wxDynamicLibrary;
+
+/// Sound data, as loaded from .wav file:
+class wxSoundData
+{
+public:
+    wxSoundData() : m_refCnt(1) {}
+    void IncRef();
+    void DecRef();
+    
+    // .wav header information:
+    unsigned m_channels;       // num of channels (mono:1, stereo:2)
+    unsigned m_samplingRate;
+    unsigned m_bitsPerSample;  // if 8, then m_data contains unsigned 8bit
+                               // samples (wxUint8), if 16 then signed 16bit
+                               // (wxInt16)
+    unsigned m_samples;        // length in samples:
+    
+    // wave data:
+    size_t   m_dataBytes;
+    wxUint8 *m_data;           // m_dataBytes bytes of data
+
+private:
+    ~wxSoundData();
+    unsigned m_refCnt;
+    wxUint8 *m_dataWithHeader; // ditto, but prefixed with .wav header
+    friend class wxSound;
+};
+
+
+/// Simple sound class:
+class wxSound : public wxSoundBase
+{
+public:
+    wxSound();
+    wxSound(const wxString& fileName, bool isResource = false);
+    wxSound(int size, const wxByte* data);
+    ~wxSound();
+
+    // Create from resource or file
+    bool Create(const wxString& fileName, bool isResource = false);
+    // Create from data
+    bool Create(int size, const wxByte* data);
+
+    bool IsOk() const { return m_data != NULL; }
+    
+    // for internal use
+    static void UnloadBackend();
+    
+protected:
+    bool DoPlay(unsigned flags);
+
+    static void EnsureBackend();
+    void Free();
+    bool LoadWAV(const wxUint8 *data, size_t length, bool copyData);
+    
+    static wxSoundBackend *ms_backend;
+#if wxUSE_LIBSDL && wxUSE_PLUGINS
+    // FIXME - temporary, until we have plugins architecture
+    static wxDynamicLibrary *ms_backendSDL;
+#endif
+
+private:
+    wxSoundData *m_data;
+};
+
+
+// ----------------------------------------------------------------------------
+// wxSoundBackend: 
+// ----------------------------------------------------------------------------
+
+// This is interface to sound playing implementation. There are multiple
+// sound architectures in use on Unix platforms and wxWindows can use several
+// of them for playback, depending on their availability at runtime; hence
+// the need for backends. This class is for use by wxWindows and people writing
+// additional backends only, it is _not_ for use by applications! 
+
+class wxSoundBackend
+{
+public:
+    virtual ~wxSoundBackend() {}
+    
+    // Returns the name of the backend (e.g. "Open Sound System")
+    virtual wxString GetName() const = 0;
+
+    // Returns priority (higher priority backends are tried first)
+    virtual int GetPriority() const = 0;
+
+    // Checks if the backend's audio system is available and the backend can
+    // be used for playback
+    virtual bool IsAvailable() const = 0;
+
+    // Returns true if the backend is capable of playing sound asynchronously.
+    // If false, then wxWindows creates a playback thread and handles async
+    // playback, otherwise it is left up to the backend (will usually be more
+    // effective)
+    virtual bool HasNativeAsyncPlayback() const = 0;
+
+    // Plays the sound. flags are same flags as those passed to wxSound::Play
+    virtual bool Play(wxSoundData *data, unsigned flags) = 0;
+};
+
+
+#endif // wxUSE_WAVE
+
+#endif