Add initial AL_EXTX_buffer_sub_data support

Note that this is an in-development extension, as noted by the EXTX moniker
instead of EXT. It's behavior is subject to change, and the extension string
will be removed (replaced with the official string once it's finalized).
Developers are discouraged from using this in production code, though feel
free to play around with it.

1 files changed, 104 insertions, 0 deletions

diff --git a/OpenAL32/alBuffer.c b/OpenAL32/alBuffer.c
index a8258d04..959d3098 100644
--- a/OpenAL32/alBuffer.c
+++ b/OpenAL32/alBuffer.c
@@ -405,6 +405,110 @@ ALAPI ALvoid ALAPIENTRY alBufferData(ALuint buffer,ALenum format,const ALvoid *d
     ProcessContext(Context);
 }
 
+/*
+*    alBufferSubDataEXT(ALuint buffer,ALenum format,ALvoid *data,ALsizei offset,ALsizei length)
+*
+*    Fill buffer with audio data
+*/
+ALvoid ALAPIENTRY alBufferSubDataEXT(ALuint buffer,ALenum format,const ALvoid *data,ALsizei offset,ALsizei length)
+{
+    ALCcontext *Context;
+    ALbuffer *ALBuf;
+
+    Context = alcGetCurrentContext();
+    SuspendContext(Context);
+
+    if(alIsBuffer(buffer) && buffer != 0)
+    {
+        ALBuf = (ALbuffer*)ALTHUNK_LOOKUPENTRY(buffer);
+        if(ALBuf->data == NULL)
+        {
+            // buffer does not have any data
+            alSetError(AL_INVALID_NAME);
+        }
+        else if(length < 0 || offset < 0 || (length > 0 && data == NULL))
+        {
+            // data is NULL or offset/length is negative
+            alSetError(AL_INVALID_VALUE);
+        }
+        else
+        {
+            switch(format)
+            {
+                case AL_FORMAT_REAR8:
+                case AL_FORMAT_REAR16:
+                case AL_FORMAT_REAR32: {
+                    ALuint OrigBytes = ((format==AL_FORMAT_REAR8) ? 1 :
+                                        ((format==AL_FORMAT_REAR16) ? 2 :
+                                         4));
+
+                    if(ALBuf->eOriginalFormat != AL_FORMAT_REAR8 &&
+                       ALBuf->eOriginalFormat != AL_FORMAT_REAR16 &&
+                       ALBuf->eOriginalFormat != AL_FORMAT_REAR32)
+                    {
+                        alSetError(AL_INVALID_ENUM);
+                        break;
+                    }
+
+                    if(ALBuf->size/4/sizeof(ALshort) < (ALuint)offset+length)
+                    {
+                        alSetError(AL_INVALID_VALUE);
+                        break;
+                    }
+
+                    ConvertDataRear(&ALBuf->data[offset*4], data, OrigBytes, length*2);
+                }   break;
+
+                case AL_FORMAT_MONO_IMA4:
+                case AL_FORMAT_STEREO_IMA4: {
+                    int Channels = aluChannelsFromFormat(ALBuf->format);
+
+                    if(ALBuf->eOriginalFormat != format)
+                    {
+                        alSetError(AL_INVALID_ENUM);
+                        break;
+                    }
+
+                    if((offset%65) != 0 || (length%65) != 0 ||
+                       ALBuf->size/Channels/sizeof(ALshort) < (ALuint)offset+length)
+                    {
+                        alSetError(AL_INVALID_VALUE);
+                        break;
+                    }
+
+                    ConvertDataIMA4(&ALBuf->data[offset*Channels], data, Channels, length/65*Channels);
+                }   break;
+
+                default: {
+                    ALuint Channels = aluChannelsFromFormat(format);
+                    ALuint Bytes = aluBytesFromFormat(format);
+
+                    if(Channels != aluChannelsFromFormat(ALBuf->format))
+                    {
+                        alSetError(AL_INVALID_ENUM);
+                        break;
+                    }
+
+                    if(ALBuf->size/Channels/sizeof(ALshort) < (ALuint)offset+length)
+                    {
+                        alSetError(AL_INVALID_VALUE);
+                        break;
+                    }
+
+                    ConvertData(&ALBuf->data[offset*Channels], data, Bytes, length*Channels);
+                }   break;
+            }
+        }
+    }
+    else
+    {
+        // Invalid Buffer Name
+        alSetError(AL_INVALID_NAME);
+    }
+
+    ProcessContext(Context);
+}
+
 
 ALAPI void ALAPIENTRY alBufferf(ALuint buffer, ALenum eParam, ALfloat flValue)
 {