text: /* $XFree86: xc/programs/Xserver/GL/glx/unpack.h,v 1.7 2004/12/10 16:06:59 alanh Exp $ */
  #ifndef __GLX_unpack_h__
  #define __GLX_unpack_h__
  
  /*
  ** License Applicability. Except to the extent portions of this file are
  ** made subject to an alternative license as permitted in the SGI Free
  ** Software License B, Version 1.1 (the "License"), the contents of this
  ** file are subject only to the provisions of the License. You may not use
  ** this file except in compliance with the License. You may obtain a copy
  ** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
  ** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
  ** 
  ** http://oss.sgi.com/projects/FreeB
  ** 
  ** Note that, as provided in the License, the Software is distributed on an
  ** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
  ** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
  ** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
  ** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
  ** 
  ** Original Code. The Original Code is: OpenGL Sample Implementation,
  ** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
  ** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
  ** Copyright in any portions created by third parties is as indicated
  ** elsewhere herein. All Rights Reserved.
  ** 
  ** Additional Notice Provisions: The application programming interfaces
  ** established by SGI in conjunction with the Original Code are The
  ** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
  ** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
  ** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
  ** Window System(R) (Version 1.3), released October 19, 1998. This software
  ** was created using the OpenGL(R) version 1.2.1 Sample Implementation
  ** published by SGI, but has not been independently verified as being
  ** compliant with the OpenGL(R) version 1.2.1 Specification.
  **
  */
  
  #define __GLX_PAD(s) (((s)+3) & (GLuint)~3)
  
  /*
  ** Fetch the context-id out of a SingleReq request pointed to by pc.
  */
  #define __GLX_GET_SINGLE_CONTEXT_TAG(pc) (((xGLXSingleReq*)pc)->contextTag)
  #define __GLX_GET_VENDPRIV_CONTEXT_TAG(pc) (((xGLXVendorPrivateReq*)pc)->contextTag)
  
  /*
  ** Fetch a double from potentially unaligned memory.
  */
  #ifdef __GLX_ALIGN64
  #define __GLX_MEM_COPY(dst,src,n)	if (src && dst) memcpy(dst,src,n)
  #define __GLX_GET_DOUBLE(dst,src)	__GLX_MEM_COPY(&dst,src,8)
  #else
  #define __GLX_GET_DOUBLE(dst,src)	(dst) = *((GLdouble*)(src))
  #endif
  
  extern void __glXMemInit(void);
  
  extern xGLXSingleReply __glXReply;
  
  #define __GLX_BEGIN_REPLY(size) \
    	__glXReply.length = __GLX_PAD(size) >> 2;	\
    	__glXReply.type = X_Reply; 			\
    	__glXReply.sequenceNumber = client->sequence;
  
  #define __GLX_SEND_HEADER() \
  	WriteToClient( client, sz_xGLXSingleReply, (char *)&__glXReply);
  
  #define __GLX_PUT_RETVAL(a) \
    	__glXReply.retval = (a);
    
  #define __GLX_PUT_SIZE(a) \
    	__glXReply.size = (a);
  
  #define __GLX_PUT_RENDERMODE(m) \
          __glXReply.pad3 = (m)
  
  /*
  ** Get a buffer to hold returned data, with the given alignment.  If we have
  ** to realloc, allocate size+align, in case the pointer has to be bumped for
  ** alignment.  The answerBuffer should already be aligned.
  **
  ** NOTE: the cast (long)res below assumes a long is large enough to hold a
  ** pointer.
  */
  #define __GLX_GET_ANSWER_BUFFER(res,cl,size,align)			 \
      if ((size) > sizeof(answerBuffer)) {				 \
  	int bump;							 \
  	if ((cl)->returnBufSize < (size)+(align)) {			 \
  	    (cl)->returnBuf = (GLbyte*)Xrealloc((cl)->returnBuf,	 \
  						(size)+(align));         \
  	    if (!(cl)->returnBuf) {					 \
  		return BadAlloc;					 \
  	    }								 \
  	    (cl)->returnBufSize = (size)+(align);			 \
  	}								 \
  	res = (char*)cl->returnBuf;					 \
  	bump = (long)(res) % (align);					 \
  	if (bump) res += (align) - (bump);				 \
      } else {								 \
  	res = (char *)answerBuffer;					 \
      }
  
  #define __GLX_PUT_BYTE() \
    	*(GLbyte *)&__glXReply.pad3 = *(GLbyte *)answer
  	  
  #define __GLX_PUT_SHORT() \
    	*(GLshort *)&__glXReply.pad3 = *(GLshort *)answer
  	  
  #define __GLX_PUT_INT() \
    	*(GLint *)&__glXReply.pad3 = *(GLint *)answer
  	  
  #define __GLX_PUT_FLOAT() \
    	*(GLfloat *)&__glXReply.pad3 = *(GLfloat *)answer
  	  
  #define __GLX_PUT_DOUBLE() \
    	*(GLdouble *)&__glXReply.pad3 = *(GLdouble *)answer
  	  
  #define __GLX_SEND_BYTE_ARRAY(len) \
  	WriteToClient(client, __GLX_PAD((len)*__GLX_SIZE_INT8), (char *)answer)
  
  #define __GLX_SEND_SHORT_ARRAY(len) \
  	WriteToClient(client, __GLX_PAD((len)*__GLX_SIZE_INT16), (char *)answer)
    
  #define __GLX_SEND_INT_ARRAY(len) \
  	WriteToClient(client, (len)*__GLX_SIZE_INT32, (char *)answer)
    
  #define __GLX_SEND_FLOAT_ARRAY(len) \
  	WriteToClient(client, (len)*__GLX_SIZE_FLOAT32, (char *)answer)
    
  #define __GLX_SEND_DOUBLE_ARRAY(len) \
  	WriteToClient(client, (len)*__GLX_SIZE_FLOAT64, (char *)answer)
  
  
  #define __GLX_SEND_VOID_ARRAY(len)  __GLX_SEND_BYTE_ARRAY(len)
  #define __GLX_SEND_UBYTE_ARRAY(len)  __GLX_SEND_BYTE_ARRAY(len)
  #define __GLX_SEND_USHORT_ARRAY(len) __GLX_SEND_SHORT_ARRAY(len)
  #define __GLX_SEND_UINT_ARRAY(len)  __GLX_SEND_INT_ARRAY(len)
  
  /*
  ** PERFORMANCE NOTE:
  ** Machine dependent optimizations abound here; these swapping macros can
  ** conceivably be replaced with routines that do the job faster.
  */
  #define __GLX_DECLARE_SWAP_VARIABLES \
  	GLbyte sw
  
  #define __GLX_DECLARE_SWAP_ARRAY_VARIABLES \
    	GLbyte *swapPC;		\
    	GLbyte *swapEnd
  
  
  #define __GLX_SWAP_INT(pc) 			\
    	sw = ((GLbyte *)(pc))[0]; 		\
    	((GLbyte *)(pc))[0] = ((GLbyte *)(pc))[3]; 	\
    	((GLbyte *)(pc))[3] = sw; 		\
    	sw = ((GLbyte *)(pc))[1]; 		\
    	((GLbyte *)(pc))[1] = ((GLbyte *)(pc))[2]; 	\
    	((GLbyte *)(pc))[2] = sw;	
  
  #define __GLX_SWAP_SHORT(pc) \
    	sw = ((GLbyte *)(pc))[0]; 		\
    	((GLbyte *)(pc))[0] = ((GLbyte *)(pc))[1]; 	\
    	((GLbyte *)(pc))[1] = sw; 	
  
  #define __GLX_SWAP_DOUBLE(pc) \
    	sw = ((GLbyte *)(pc))[0]; 		\
    	((GLbyte *)(pc))[0] = ((GLbyte *)(pc))[7]; 	\
    	((GLbyte *)(pc))[7] = sw; 		\
    	sw = ((GLbyte *)(pc))[1]; 		\
    	((GLbyte *)(pc))[1] = ((GLbyte *)(pc))[6]; 	\
    	((GLbyte *)(pc))[6] = sw;			\
    	sw = ((GLbyte *)(pc))[2]; 		\
    	((GLbyte *)(pc))[2] = ((GLbyte *)(pc))[5]; 	\
    	((GLbyte *)(pc))[5] = sw;			\
    	sw = ((GLbyte *)(pc))[3]; 		\
    	((GLbyte *)(pc))[3] = ((GLbyte *)(pc))[4]; 	\
    	((GLbyte *)(pc))[4] = sw;	
  
  #define __GLX_SWAP_FLOAT(pc) \
    	sw = ((GLbyte *)(pc))[0]; 		\
    	((GLbyte *)(pc))[0] = ((GLbyte *)(pc))[3]; 	\
    	((GLbyte *)(pc))[3] = sw; 		\
    	sw = ((GLbyte *)(pc))[1]; 		\
    	((GLbyte *)(pc))[1] = ((GLbyte *)(pc))[2]; 	\
    	((GLbyte *)(pc))[2] = sw;	
  
  #define __GLX_SWAP_INT_ARRAY(pc, count) \
    	swapPC = ((GLbyte *)(pc));		\
    	swapEnd = ((GLbyte *)(pc)) + (count)*__GLX_SIZE_INT32;\
    	while (swapPC < swapEnd) {		\
  	    __GLX_SWAP_INT(swapPC);		\
  	    swapPC += __GLX_SIZE_INT32;		\
  	}
  	
  #define __GLX_SWAP_SHORT_ARRAY(pc, count) \
    	swapPC = ((GLbyte *)(pc));		\
    	swapEnd = ((GLbyte *)(pc)) + (count)*__GLX_SIZE_INT16;\
    	while (swapPC < swapEnd) {		\
  	    __GLX_SWAP_SHORT(swapPC);		\
  	    swapPC += __GLX_SIZE_INT16;		\
  	}
  	
  #define __GLX_SWAP_DOUBLE_ARRAY(pc, count) \
    	swapPC = ((GLbyte *)(pc));		\
    	swapEnd = ((GLbyte *)(pc)) + (count)*__GLX_SIZE_FLOAT64;\
    	while (swapPC < swapEnd) {		\
  	    __GLX_SWAP_DOUBLE(swapPC);		\
  	    swapPC += __GLX_SIZE_FLOAT64;	\
  	}
      
  #define __GLX_SWAP_FLOAT_ARRAY(pc, count) \
    	swapPC = ((GLbyte *)(pc));		\
    	swapEnd = ((GLbyte *)(pc)) + (count)*__GLX_SIZE_FLOAT32;\
    	while (swapPC < swapEnd) {		\
  	    __GLX_SWAP_FLOAT(swapPC);		\
  	    swapPC += __GLX_SIZE_FLOAT32;	\
  	}
  
  #define __GLX_SWAP_REPLY_HEADER() \
    	__GLX_SWAP_SHORT(&__glXReply.sequenceNumber); \
    	__GLX_SWAP_INT(&__glXReply.length);
  
  #define __GLX_SWAP_REPLY_RETVAL() \
    	__GLX_SWAP_INT(&__glXReply.retval)
  
  #define __GLX_SWAP_REPLY_SIZE() \
    	__GLX_SWAP_INT(&__glXReply.size)
  
  #endif /* !__GLX_unpack_h__ */
  
  
  
  
  
  