glxcmdsswap.c

/*
** 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 FONT_PCF
#ifdef HAVE_DIX_CONFIG_H
#include <dix-config.h>
#endif

#include "glxserver.h"
#include "glxutil.h"
#include <GL/glxtokens.h>
#include <unpack.h>
#include <g_disptab.h>
#include <g_disptab_EXT.h>
#include <pixmapstr.h>
#include <windowstr.h>
#include "glxext.h"

static int __glXSwapGetFBConfigsSGIX(__GLXclientState *cl, GLbyte *pc);
static int __glXSwapCreateContextWithConfigSGIX(__GLXclientState *cl, GLbyte *pc);
static int __glXSwapCreateGLXPixmapWithConfigSGIX(__GLXclientState *cl, GLbyte *pc);
static int __glXSwapMakeCurrentReadSGI(__GLXclientState *cl, GLbyte *pc);

/************************************************************************/

/*
** Byteswapping versions of GLX commands.  In most cases they just swap
** the incoming arguments and then call the unswapped routine.  For commands
** that have replies, a separate swapping routine for the reply is provided;
** it is called at the end of the unswapped routine.
*/

int __glXSwapCreateContext(__GLXclientState *cl, GLbyte *pc)
{
    xGLXCreateContextReq *req = (xGLXCreateContextReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->context);
    __GLX_SWAP_INT(&req->visual);
    __GLX_SWAP_INT(&req->screen);
    __GLX_SWAP_INT(&req->shareList);

    return DoCreateContext( cl, req->context, req->shareList, req->visual,
			    req->screen, req->isDirect );
}

int __glXSwapCreateNewContext(__GLXclientState *cl, GLbyte *pc)
{
    xGLXCreateNewContextReq *req = (xGLXCreateNewContextReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->context);
    __GLX_SWAP_INT(&req->fbconfig);
    __GLX_SWAP_INT(&req->screen);
    __GLX_SWAP_INT(&req->renderType);
    __GLX_SWAP_INT(&req->shareList);

    return DoCreateContext( cl, req->context, req->shareList, req->fbconfig,
			    req->screen, req->isDirect );
}

int __glXSwapCreateContextWithConfigSGIX(__GLXclientState *cl, GLbyte *pc)
{
    xGLXCreateContextWithConfigSGIXReq *req =
	(xGLXCreateContextWithConfigSGIXReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->context);
    __GLX_SWAP_INT(&req->fbconfig);
    __GLX_SWAP_INT(&req->screen);
    __GLX_SWAP_INT(&req->renderType);
    __GLX_SWAP_INT(&req->shareList);

    return DoCreateContext( cl, req->context, req->shareList, req->fbconfig,
			    req->screen, req->isDirect );
}

int __glXSwapDestroyContext(__GLXclientState *cl, GLbyte *pc)
{
    xGLXDestroyContextReq *req = (xGLXDestroyContextReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->context);

    return __glXDestroyContext(cl, pc);
}

int __glXSwapMakeCurrent(__GLXclientState *cl, GLbyte *pc)
{
    xGLXMakeCurrentReq *req = (xGLXMakeCurrentReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->drawable);
    __GLX_SWAP_INT(&req->context);
    __GLX_SWAP_INT(&req->oldContextTag);

    return DoMakeCurrent( cl, req->drawable, req->drawable,
			  req->context, req->oldContextTag );
}

int __glXSwapMakeContextCurrent(__GLXclientState *cl, GLbyte *pc)
{
    xGLXMakeContextCurrentReq *req = (xGLXMakeContextCurrentReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->drawable);
    __GLX_SWAP_INT(&req->readdrawable);
    __GLX_SWAP_INT(&req->context);
    __GLX_SWAP_INT(&req->oldContextTag);

    return DoMakeCurrent( cl, req->drawable, req->readdrawable,
			  req->context, req->oldContextTag );
}

int __glXSwapMakeCurrentReadSGI(__GLXclientState *cl, GLbyte *pc)
{
    xGLXMakeCurrentReadSGIReq *req = (xGLXMakeCurrentReadSGIReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->drawable);
    __GLX_SWAP_INT(&req->readable);
    __GLX_SWAP_INT(&req->context);
    __GLX_SWAP_INT(&req->oldContextTag);

    return DoMakeCurrent( cl, req->drawable, req->readable,
			  req->context, req->oldContextTag );
}

int __glXSwapIsDirect(__GLXclientState *cl, GLbyte *pc)
{
    xGLXIsDirectReq *req = (xGLXIsDirectReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->context);

    return __glXIsDirect(cl, pc);
}

int __glXSwapQueryVersion(__GLXclientState *cl, GLbyte *pc)
{
    xGLXQueryVersionReq *req = (xGLXQueryVersionReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->majorVersion);
    __GLX_SWAP_INT(&req->minorVersion);

    return __glXQueryVersion(cl, pc);
}

int __glXSwapWaitGL(__GLXclientState *cl, GLbyte *pc)
{
    xGLXWaitGLReq *req = (xGLXWaitGLReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->contextTag);

    return __glXWaitGL(cl, pc);
}

int __glXSwapWaitX(__GLXclientState *cl, GLbyte *pc)
{
    xGLXWaitXReq *req = (xGLXWaitXReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->contextTag);

    return __glXWaitX(cl, pc);
}

int __glXSwapCopyContext(__GLXclientState *cl, GLbyte *pc)
{
    xGLXCopyContextReq *req = (xGLXCopyContextReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->source);
    __GLX_SWAP_INT(&req->dest);
    __GLX_SWAP_INT(&req->mask);

    return __glXCopyContext(cl, pc);
}

int __glXSwapGetVisualConfigs(__GLXclientState *cl, GLbyte *pc)
{
    xGLXGetVisualConfigsReq *req = (xGLXGetVisualConfigsReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_INT(&req->screen);
    return DoGetVisualConfigs( cl, req->screen, GL_TRUE );
}

int __glXSwapGetFBConfigs(__GLXclientState *cl, GLbyte *pc)
{
    xGLXGetFBConfigsReq *req = (xGLXGetFBConfigsReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_INT(&req->screen);
    return DoGetFBConfigs( cl, req->screen, GL_TRUE );
}

int __glXSwapGetFBConfigsSGIX(__GLXclientState *cl, GLbyte *pc)
{
    xGLXGetFBConfigsSGIXReq *req = (xGLXGetFBConfigsSGIXReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_INT(&req->screen);
    return DoGetFBConfigs( cl, req->screen, GL_TRUE );
}

int __glXSwapCreateGLXPixmap(__GLXclientState *cl, GLbyte *pc)
{
    xGLXCreateGLXPixmapReq *req = (xGLXCreateGLXPixmapReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->screen);
    __GLX_SWAP_INT(&req->visual);
    __GLX_SWAP_INT(&req->pixmap);
    __GLX_SWAP_INT(&req->glxpixmap);

    return DoCreateGLXPixmap( cl, req->visual, req->screen,
			      req->pixmap, req->glxpixmap );
}

int __glXSwapCreatePixmap(__GLXclientState *cl, GLbyte *pc)
{
    xGLXCreatePixmapReq *req = (xGLXCreatePixmapReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->screen);
    __GLX_SWAP_INT(&req->fbconfig);
    __GLX_SWAP_INT(&req->pixmap);
    __GLX_SWAP_INT(&req->glxpixmap);

    return DoCreateGLXPixmap( cl, req->fbconfig, req->screen,
			      req->pixmap, req->glxpixmap );
}

int __glXSwapCreateGLXPixmapWithConfigSGIX(__GLXclientState *cl, GLbyte *pc)
{
    xGLXCreateGLXPixmapWithConfigSGIXReq *req = 
	(xGLXCreateGLXPixmapWithConfigSGIXReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->screen);
    __GLX_SWAP_INT(&req->fbconfig);
    __GLX_SWAP_INT(&req->pixmap);
    __GLX_SWAP_INT(&req->glxpixmap);

    return DoCreateGLXPixmap( cl, req->fbconfig, req->screen,
			      req->pixmap, req->glxpixmap );
}

int __glXSwapDestroyGLXPixmap(__GLXclientState *cl, GLbyte *pc)
{
    xGLXDestroyGLXPixmapReq *req = (xGLXDestroyGLXPixmapReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->glxpixmap);

    return __glXDestroyGLXPixmap(cl, pc);
}

int __glXSwapSwapBuffers(__GLXclientState *cl, GLbyte *pc)
{
    xGLXSwapBuffersReq *req = (xGLXSwapBuffersReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->contextTag);
    __GLX_SWAP_INT(&req->drawable);

    return __glXSwapBuffers(cl, pc);
}

int __glXSwapUseXFont(__GLXclientState *cl, GLbyte *pc)
{
    xGLXUseXFontReq *req = (xGLXUseXFontReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->contextTag);
    __GLX_SWAP_INT(&req->font);
    __GLX_SWAP_INT(&req->first);
    __GLX_SWAP_INT(&req->count);
    __GLX_SWAP_INT(&req->listBase);

    return __glXUseXFont(cl, pc);
}


int __glXSwapQueryExtensionsString(__GLXclientState *cl, GLbyte *pc)
{
    xGLXQueryExtensionsStringReq *req = NULL;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->screen);

    return __glXQueryExtensionsString(cl, pc);
}

int __glXSwapQueryServerString(__GLXclientState *cl, GLbyte *pc)
{
    xGLXQueryServerStringReq *req = (xGLXQueryServerStringReq *)pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->screen);
    __GLX_SWAP_INT(&req->name);

    return __glXQueryServerString(cl, pc);
}

int __glXSwapClientInfo(__GLXclientState *cl, GLbyte *pc)
{
    xGLXClientInfoReq *req = (xGLXClientInfoReq *)pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->major);
    __GLX_SWAP_INT(&req->minor);
    __GLX_SWAP_INT(&req->numbytes);

    return __glXClientInfo(cl, pc);
}

int __glXSwapQueryContextInfoEXT(__GLXclientState *cl, GLbyte *pc)
{
    xGLXQueryContextInfoEXTReq *req = (xGLXQueryContextInfoEXTReq *) pc;
    __GLX_DECLARE_SWAP_VARIABLES;

    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->context);

    return __glXQueryContextInfoEXT(cl, pc);
}

/************************************************************************/

/*
** Swap replies.
*/

void __glXSwapMakeCurrentReply(ClientPtr client, xGLXMakeCurrentReply *reply)
{
    __GLX_DECLARE_SWAP_VARIABLES;
    __GLX_SWAP_SHORT(&reply->sequenceNumber);
    __GLX_SWAP_INT(&reply->length);
    __GLX_SWAP_INT(&reply->contextTag);
    WriteToClient(client, sz_xGLXMakeCurrentReply, reply);
}

void __glXSwapIsDirectReply(ClientPtr client, xGLXIsDirectReply *reply)
{
    __GLX_DECLARE_SWAP_VARIABLES;
    __GLX_SWAP_SHORT(&reply->sequenceNumber);
    __GLX_SWAP_INT(&reply->length);
    WriteToClient(client, sz_xGLXIsDirectReply, reply);
}

void __glXSwapQueryVersionReply(ClientPtr client, xGLXQueryVersionReply *reply)
{
    __GLX_DECLARE_SWAP_VARIABLES;
    __GLX_SWAP_SHORT(&reply->sequenceNumber);
    __GLX_SWAP_INT(&reply->length);
    __GLX_SWAP_INT(&reply->majorVersion);
    __GLX_SWAP_INT(&reply->minorVersion);
    WriteToClient(client, sz_xGLXQueryVersionReply, reply);
}

void glxSwapQueryExtensionsStringReply(ClientPtr client,
				       xGLXQueryExtensionsStringReply *reply, char *buf)
{
    int length = reply->length;
    __GLX_DECLARE_SWAP_VARIABLES;
    __GLX_DECLARE_SWAP_ARRAY_VARIABLES;
    __GLX_SWAP_SHORT(&reply->sequenceNumber);
    __GLX_SWAP_INT(&reply->length);
    __GLX_SWAP_INT(&reply->n);
    WriteToClient(client, sz_xGLXQueryExtensionsStringReply, reply);
    __GLX_SWAP_INT_ARRAY((int *)buf, length);
    WriteToClient(client, length << 2, buf);
}

void glxSwapQueryServerStringReply(ClientPtr client,
				   xGLXQueryServerStringReply *reply, char *buf)
{
    int length = reply->length;
    __GLX_DECLARE_SWAP_VARIABLES;
    __GLX_SWAP_SHORT(&reply->sequenceNumber);
    __GLX_SWAP_INT(&reply->length);
    __GLX_SWAP_INT(&reply->n);
    WriteToClient(client, sz_xGLXQueryServerStringReply, reply);
    /** no swap is needed for an array of chars **/
    /* __GLX_SWAP_INT_ARRAY((int *)buf, length); */
    WriteToClient(client, length << 2, buf);
}

void __glXSwapQueryContextInfoEXTReply(ClientPtr client, xGLXQueryContextInfoEXTReply *reply, int *buf)
{
    int length = reply->length;
    __GLX_DECLARE_SWAP_VARIABLES;
    __GLX_DECLARE_SWAP_ARRAY_VARIABLES;
    __GLX_SWAP_SHORT(&reply->sequenceNumber);
    __GLX_SWAP_INT(&reply->length);
    __GLX_SWAP_INT(&reply->n);
    WriteToClient(client, sz_xGLXQueryContextInfoEXTReply, reply);
    __GLX_SWAP_INT_ARRAY((int *)buf, length);
    WriteToClient(client, length << 2, buf);
}


/************************************************************************/

/*
** Render and Renderlarge are not in the GLX API.  They are used by the GLX
** client library to send batches of GL rendering commands.
*/

int __glXSwapRender(__GLXclientState *cl, GLbyte *pc)
{
    xGLXRenderReq *req;
    ClientPtr client= cl->client;
    int left, cmdlen, error;
    int commandsDone;
    CARD16 opcode;
    __GLXrenderHeader *hdr;
    __GLXcontext *cx;
    __GLX_DECLARE_SWAP_VARIABLES;

    /*
    ** NOTE: much of this code also appears in the nonswapping version of this
    ** routine, __glXRender().  Any changes made here should also be
    ** duplicated there.
    */
    
    req = (xGLXRenderReq *) pc;
    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->contextTag);

    cx = __glXForceCurrent(cl, req->contextTag, &error);
    if (!cx) {
	return error;
    }

    commandsDone = 0;
    pc += sz_xGLXRenderReq;
    left = (req->length << 2) - sz_xGLXRenderReq;
    while (left > 0) {
        __GLXrenderSizeData *entry;
        int extra = 0;
	void (* proc)(GLbyte *);

	/*
	** Verify that the header length and the overall length agree.
	** Also, each command must be word aligned.
	*/
	hdr = (__GLXrenderHeader *) pc;
	__GLX_SWAP_SHORT(&hdr->length);
	__GLX_SWAP_SHORT(&hdr->opcode);
	cmdlen = hdr->length;
	opcode = hdr->opcode;

	if (left < cmdlen)
	return BadLength;

	if ( (opcode >= __GLX_MIN_RENDER_OPCODE) && 
	     (opcode <= __GLX_MAX_RENDER_OPCODE) ) {
	    entry = &__glXRenderSizeTable[opcode];
	    proc = __glXSwapRenderTable[opcode];
#if __GLX_MAX_RENDER_OPCODE_EXT > __GLX_MIN_RENDER_OPCODE_EXT
	} else if ( (opcode >= __GLX_MIN_RENDER_OPCODE_EXT) && 
	     (opcode <= __GLX_MAX_RENDER_OPCODE_EXT) ) {
	    int index = opcode - __GLX_MIN_RENDER_OPCODE_EXT;
	    entry = &__glXRenderSizeTable_EXT[index];
	    proc = __glXSwapRenderTable_EXT[index];
#endif /* __GLX_MAX_RENDER_OPCODE_EXT > __GLX_MIN_RENDER_OPCODE_EXT */
	} else {
	    client->errorValue = commandsDone;
	    return __glXBadRenderRequest;
	}
        if (!entry->bytes) {
            /* unused opcode */
	    client->errorValue = commandsDone;
            return __glXBadRenderRequest;
        }

	if (cmdlen < entry->bytes) {
	    return BadLength;
	}

        if (entry->varsize) {
            /* variable size command */
	    extra = (*entry->varsize)(pc + __GLX_RENDER_HDR_SIZE, True,
				      left - __GLX_RENDER_HDR_SIZE);
            if (extra < 0) {
                return BadLength;
            }
        }
	if (cmdlen != safe_pad(safe_add(entry->bytes, extra))) {
	    return BadLength;
	}

	/*
	** Skip over the header and execute the command.  We allow the
	** caller to trash the command memory.  This is useful especially
	** for things that require double alignment - they can just shift
	** the data towards lower memory (trashing the header) by 4 bytes
	** and achieve the required alignment.
	*/
	(*proc)(pc + __GLX_RENDER_HDR_SIZE);
	pc += cmdlen;
	left -= cmdlen;
	commandsDone++;
    }
    __GLX_NOTE_UNFLUSHED_CMDS(cx);
    return Success;
}

/*
** Execute a large rendering request (one that spans multiple X requests).
*/
int __glXSwapRenderLarge(__GLXclientState *cl, GLbyte *pc)
{
    xGLXRenderLargeReq *req;
    ClientPtr client= cl->client;
    size_t dataBytes;
    void (*proc)(GLbyte *);
    __GLXrenderLargeHeader *hdr;
    __GLXcontext *cx;
    int error;
    CARD16 opcode;
    __GLX_DECLARE_SWAP_VARIABLES;

    /*
    ** NOTE: much of this code also appears in the nonswapping version of this
    ** routine, __glXRenderLarge().  Any changes made here should also be
    ** duplicated there.
    */
    
    REQUEST_AT_LEAST_SIZE(xGLXRenderLargeReq);

    req = (xGLXRenderLargeReq *) pc;
    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->contextTag);
    __GLX_SWAP_INT(&req->dataBytes);
    __GLX_SWAP_SHORT(&req->requestNumber);
    __GLX_SWAP_SHORT(&req->requestTotal);
    cx = __glXForceCurrent(cl, req->contextTag, &error);
    if (!cx) {
	/* Reset in case this isn't 1st request. */
	__glXResetLargeCommandStatus(cl);
	return error;
    }
    if (safe_pad(req->dataBytes) < 0)
        return BadLength;

    dataBytes = req->dataBytes;

    /*
    ** Check the request length.
    */
    if ((req->length << 2) != safe_pad(dataBytes) + sz_xGLXRenderLargeReq) {
	client->errorValue = req->length;
	/* Reset in case this isn't 1st request. */
	__glXResetLargeCommandStatus(cl);
	return BadLength;
    }
    pc += sz_xGLXRenderLargeReq;
    
    if (cl->largeCmdRequestsSoFar == 0) {
	__GLXrenderSizeData *entry;
	int extra = 0;
        int left = (req->length << 2) - sz_xGLXRenderLargeReq;
	size_t cmdlen;
	/*
	** This is the first request of a multi request command.
	** Make enough space in the buffer, then copy the entire request.
	*/
	if (req->requestNumber != 1) {
	    client->errorValue = req->requestNumber;
	    return __glXBadLargeRequest;
	}
	if (dataBytes < __GLX_RENDER_LARGE_HDR_SIZE)
	    return BadLength;

	hdr = (__GLXrenderLargeHeader *) pc;
	__GLX_SWAP_INT(&hdr->length);
	__GLX_SWAP_INT(&hdr->opcode);
	opcode = hdr->opcode;

	if ((cmdlen = safe_pad(hdr->length)) < 0)
	    return BadLength;

	if ( (opcode >= __GLX_MIN_RENDER_OPCODE) && 
	     (opcode <= __GLX_MAX_RENDER_OPCODE) ) {
	    entry = &__glXRenderSizeTable[opcode];
	    proc = __glXSwapRenderTable[opcode];
#if __GLX_MAX_RENDER_OPCODE_EXT > __GLX_MIN_RENDER_OPCODE_EXT
	} else if ( (opcode >= __GLX_MIN_RENDER_OPCODE_EXT) && 
	     (opcode <= __GLX_MAX_RENDER_OPCODE_EXT) ) {
	    int index = opcode - __GLX_MIN_RENDER_OPCODE_EXT;
	    entry = &__glXRenderSizeTable_EXT[index];
	    proc = __glXSwapRenderTable_EXT[index];
#endif /* __GLX_MAX_RENDER_OPCODE_EXT > __GLX_MIN_RENDER_OPCODE_EXT */
	} else {
	    client->errorValue = opcode;
	    return __glXBadLargeRequest;
	}

        if (!entry->bytes) {
            /* unused opcode */
            client->errorValue = opcode;
            return __glXBadLargeRequest;
        }
	if (entry->varsize) {
	    /*
	    ** If it's a variable-size command (a command whose length must
	    ** be computed from its parameters), all the parameters needed
	    ** will be in the 1st request, so it's okay to do this.
	    */
	    extra = (*entry->varsize)(pc + __GLX_RENDER_LARGE_HDR_SIZE, True,
				      left - __GLX_RENDER_LARGE_HDR_SIZE);
	    if (extra < 0) {
		return BadLength;
	    }
	}
        /* the +4 is safe because we know entry->bytes is small */
        if (cmdlen != safe_pad(safe_add(entry->bytes + 4, extra))) {
            return BadLength;
        }

	/*
	** Make enough space in the buffer, then copy the entire request.
	*/
	if (cl->largeCmdBufSize < cmdlen) {
	    if (!cl->largeCmdBuf) {
		cl->largeCmdBuf = (GLbyte *) malloc(cmdlen);
	    } else {
		cl->largeCmdBuf = (GLbyte *) realloc(cl->largeCmdBuf, cmdlen);
	    }
	    if (!cl->largeCmdBuf) {
		return BadAlloc;
	    }
	    cl->largeCmdBufSize = cmdlen;
	}
	memcpy(cl->largeCmdBuf, pc, dataBytes);

	cl->largeCmdBytesSoFar = dataBytes;
	cl->largeCmdBytesTotal = cmdlen;
	cl->largeCmdRequestsSoFar = 1;
	cl->largeCmdRequestsTotal = req->requestTotal;
	return Success;
	
    } else {
	/*
	** We are receiving subsequent (i.e. not the first) requests of a
	** multi request command.
	*/
        int bytesSoFar; /* including this packet */

	/*
	** Check the request number and the total request count.
	*/
	if (req->requestNumber != cl->largeCmdRequestsSoFar + 1) {
	    client->errorValue = req->requestNumber;
	    __glXResetLargeCommandStatus(cl);
	    return __glXBadLargeRequest;
	}
	if (req->requestTotal != cl->largeCmdRequestsTotal) {
	    client->errorValue = req->requestTotal;
	    __glXResetLargeCommandStatus(cl);
	    return __glXBadLargeRequest;
	}

	/*
	** Check that we didn't get too much data.
	*/
        if ((bytesSoFar = safe_add(cl->largeCmdBytesSoFar, dataBytes)) < 0) {
            client->errorValue = dataBytes;
            __glXResetLargeCommandStatus(cl);
            return __glXBadLargeRequest;
        }

        if (bytesSoFar > cl->largeCmdBytesTotal) {
	    client->errorValue = dataBytes;
	    __glXResetLargeCommandStatus(cl);
	    return __glXBadLargeRequest;
	}
	memcpy(cl->largeCmdBuf + cl->largeCmdBytesSoFar, pc, dataBytes);
	cl->largeCmdBytesSoFar += dataBytes;
	cl->largeCmdRequestsSoFar++;

	if (req->requestNumber == cl->largeCmdRequestsTotal) {
	    /*
	    ** This is the last request; it must have enough bytes to complete
	    ** the command.
	    */
            /* NOTE: the pad macro below is needed because the client library
             ** pads the total byte count, but not the per-request byte counts.
             ** The Protocol Encoding says the total byte count should not be
             ** padded, so a proposal will be made to the ARB to relax the
             ** padding constraint on the total byte count, thus preserving
             ** backward compatibility.  Meanwhile, the padding done below
             ** fixes a bug that did not allow large commands of odd sizes to
             ** be accepted by the server.
	    */

	    if (safe_pad(cl->largeCmdBytesSoFar) != cl->largeCmdBytesTotal) {
		client->errorValue = dataBytes;
		__glXResetLargeCommandStatus(cl);
		return __glXBadLargeRequest;
	    }
	    hdr = (__GLXrenderLargeHeader *) cl->largeCmdBuf;
	    /*
	    ** The opcode and length field in the header had already been
	    ** swapped when the first request was received.
	    */

	    /*
	    ** Use the opcode to index into the procedure table.
	    */
	    opcode = hdr->opcode;
	    if ( (opcode >= __GLX_MIN_RENDER_OPCODE) && 
		 (opcode <= __GLX_MAX_RENDER_OPCODE) ) {
		proc = __glXSwapRenderTable[opcode];
#if __GLX_MAX_RENDER_OPCODE_EXT > __GLX_MIN_RENDER_OPCODE_EXT
	    } else if ( (opcode >= __GLX_MIN_RENDER_OPCODE_EXT) && 
		 (opcode <= __GLX_MAX_RENDER_OPCODE_EXT) ) {
		int index = opcode - __GLX_MIN_RENDER_OPCODE_EXT;
		proc = __glXSwapRenderTable_EXT[index];
#endif /* __GLX_MAX_RENDER_OPCODE_EXT > __GLX_MIN_RENDER_OPCODE_EXT */
	    } else {
		client->errorValue = opcode;
		return __glXBadLargeRequest;
	    }

	    /*
	    ** Skip over the header and execute the command.
	    */
	    (*proc)(cl->largeCmdBuf + __GLX_RENDER_LARGE_HDR_SIZE);
	    __GLX_NOTE_UNFLUSHED_CMDS(cx);

	    /*
	    ** Reset for the next RenderLarge series.
	    */
	    __glXResetLargeCommandStatus(cl);
	} else {
	    /*
	    ** This is neither the first nor the last request.
	    */
	}
	return Success;
    }
}

/************************************************************************/

/*
** No support is provided for the vendor-private requests other than
** allocating these entry points in the dispatch table.
*/

int __glXSwapVendorPrivate(__GLXclientState *cl, GLbyte *pc)
{
    ClientPtr client = cl->client;
    xGLXVendorPrivateReq *req;
    GLint vendorcode;

    __GLX_DECLARE_SWAP_VARIABLES;
    REQUEST_AT_LEAST_SIZE(xGLXVendorPrivateReq);

    req = (xGLXVendorPrivateReq *) pc;
    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->vendorCode);

    vendorcode = req->vendorCode;

#ifndef __DARWIN__
    switch( vendorcode ) {
    case X_GLvop_SampleMaskSGIS:
	__GLX_SWAP_FLOAT(pc + 4);
	__GLX_SWAP_INT(pc + 8);
	glSampleMaskSGIS(*(GLfloat *)(pc + 4),
			 *(GLboolean *)(pc + 8));
	return Success;
    case X_GLvop_SamplePatternSGIS:
	__GLX_SWAP_INT(pc + 4);
	glSamplePatternSGIS( *(GLenum *)(pc + 4));
	return Success;
    }
#endif


    if ((vendorcode >= __GLX_MIN_VENDPRIV_OPCODE_EXT) &&
          (vendorcode <= __GLX_MAX_VENDPRIV_OPCODE_EXT))  {
	(*__glXSwapVendorPrivTable_EXT[vendorcode-__GLX_MIN_VENDPRIV_OPCODE_EXT])(cl, (GLbyte*)req);
	return Success;
    }
    cl->client->errorValue = req->vendorCode;
    return __glXUnsupportedPrivateRequest;
}

int __glXSwapVendorPrivateWithReply(__GLXclientState *cl, GLbyte *pc)
{
    ClientPtr client = cl->client;
    xGLXVendorPrivateWithReplyReq *req;
    GLint vendorcode;

    __GLX_DECLARE_SWAP_VARIABLES;
    REQUEST_AT_LEAST_SIZE(xGLXVendorPrivateWithReplyReq);

    req = (xGLXVendorPrivateWithReplyReq *) pc;
    __GLX_SWAP_SHORT(&req->length);
    __GLX_SWAP_INT(&req->vendorCode);

    vendorcode = req->vendorCode;

    switch (vendorcode) {
      case X_GLXvop_QueryContextInfoEXT:
	return __glXSwapQueryContextInfoEXT(cl, pc);
      case X_GLXvop_MakeCurrentReadSGI:
	return __glXSwapMakeCurrentReadSGI(cl, pc);
      case X_GLXvop_GetFBConfigsSGIX:
	return __glXSwapGetFBConfigsSGIX(cl, pc);
      case X_GLXvop_CreateContextWithConfigSGIX:
	return __glXSwapCreateContextWithConfigSGIX(cl, pc);
      case X_GLXvop_CreateGLXPixmapWithConfigSGIX:
	return __glXSwapCreateGLXPixmapWithConfigSGIX(cl, pc);
      default:
	break;
    }


    if ((vendorcode >= __GLX_MIN_VENDPRIV_OPCODE_EXT) &&
          (vendorcode <= __GLX_MAX_VENDPRIV_OPCODE_EXT))  {
	return (*__glXSwapVendorPrivTable_EXT[vendorcode-__GLX_MIN_VENDPRIV_OPCODE_EXT])(cl, (GLbyte*)req);
    }
    cl->client->errorValue = req->vendorCode;
    return __glXUnsupportedPrivateRequest;
}