glxcmds.c

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

/*
 * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008)
 * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice including the dates of first publication and
 * either this permission notice or a reference to
 * http://oss.sgi.com/projects/FreeB/
 * shall be included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 * Except as contained in this notice, the name of Silicon Graphics, Inc.
 * shall not be used in advertising or otherwise to promote the sale, use or
 * other dealings in this Software without prior written authorization from
 * Silicon Graphics, Inc.
 */

/**
 * \file glxcmds.c
 * Client-side GLX interface.
 */

#include "glxclient.h"
#include "glapi.h"
#include "glxextensions.h"
#include "glcontextmodes.h"
#include "glheader.h"

#ifdef GLX_DIRECT_RENDERING
#include <sys/time.h>
#include <X11/extensions/xf86vmode.h>
#include "xf86dri.h"
#endif

static const char __glXGLXClientVendorName[] = "SGI";
static const char __glXGLXClientVersion[] = "1.4";


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

#ifdef GLX_DIRECT_RENDERING

static Bool windowExistsFlag;
static int windowExistsErrorHandler(Display *dpy, XErrorEvent *xerr)
{
    if (xerr->error_code == BadWindow) {
	windowExistsFlag = GL_FALSE;
    }
    return 0;
}

/**
 * Find drawables in the local hash that have been destroyed on the
 * server.
 * 
 * \param dpy    Display to destroy drawables for
 * \param screen Screen number to destroy drawables for
 */
static void GarbageCollectDRIDrawables(Display *dpy, __GLXscreenConfigs *sc)
{
    XID draw;
    __GLXDRIdrawable *pdraw;
    XWindowAttributes xwa;
    int (*oldXErrorHandler)(Display *, XErrorEvent *);

    /* Set no-op error handler so Xlib doesn't bail out if the windows
     * has alreay been destroyed on the server. */
    XSync(dpy, GL_FALSE);
    oldXErrorHandler = XSetErrorHandler(windowExistsErrorHandler);

    if (__glxHashFirst(sc->drawHash, &draw, (void *)&pdraw) == 1) {
	do {
	    windowExistsFlag = GL_TRUE;
	    XGetWindowAttributes(dpy, draw, &xwa); /* dummy request */
	    if (!windowExistsFlag) {
		/* Destroy the local drawable data, if the drawable no
		   longer exists in the Xserver */
		(*pdraw->destroyDrawable)(pdraw);
                __glxHashDelete(sc->drawHash, draw);
	    }
	} while (__glxHashNext(sc->drawHash, &draw, (void *)&pdraw) == 1);
    }

    XSync(dpy, GL_FALSE);
    XSetErrorHandler(oldXErrorHandler);
}

extern __GLXDRIdrawable *
GetGLXDRIDrawable(Display *dpy, GLXDrawable drawable, int * const scrn_num);

/**
 * Get the __DRIdrawable for the drawable associated with a GLXContext
 * 
 * \param dpy       The display associated with \c drawable.
 * \param drawable  GLXDrawable whose __DRIdrawable part is to be retrieved.
 * \param scrn_num  If non-NULL, the drawables screen is stored there
 * \returns  A pointer to the context's __DRIdrawable on success, or NULL if
 *           the drawable is not associated with a direct-rendering context.
 */
_X_HIDDEN __GLXDRIdrawable *
GetGLXDRIDrawable(Display *dpy, GLXDrawable drawable, int * const scrn_num)
{
    __GLXdisplayPrivate *priv = __glXInitialize(dpy);
    __GLXDRIdrawable *pdraw;
    const unsigned  screen_count = ScreenCount(dpy);
    unsigned   i;
    __GLXscreenConfigs *psc;

    if (priv == NULL)
	return NULL;
    
    for (i = 0; i < screen_count; i++) {
	psc = &priv->screenConfigs[i];
	if (psc->drawHash == NULL)
	    continue;

	if (__glxHashLookup(psc->drawHash, drawable, (void *) &pdraw) == 0) {
	    if (scrn_num != NULL)
		*scrn_num = i;
	    return pdraw;
	}
    }

    return NULL;
}

#endif


/**
 * Get the GLX per-screen data structure associated with a GLX context.
 * 
 * \param dpy   Display for which the GLX per-screen information is to be
 *              retrieved.
 * \param scrn  Screen on \c dpy for which the GLX per-screen information is
 *              to be retrieved.
 * \returns A pointer to the GLX per-screen data if \c dpy and \c scrn
 *          specify a valid GLX screen, or NULL otherwise.
 * 
 * \todo Should this function validate that \c scrn is within the screen
 *       number range for \c dpy?
 */

static __GLXscreenConfigs *
GetGLXScreenConfigs(Display *dpy, int scrn)
{
    __GLXdisplayPrivate * const priv = __glXInitialize(dpy);

    return (priv->screenConfigs != NULL) ? &priv->screenConfigs[scrn] : NULL;
}


static int
GetGLXPrivScreenConfig( Display *dpy, int scrn, __GLXdisplayPrivate ** ppriv,
			__GLXscreenConfigs ** ppsc )
{
    /* Initialize the extension, if needed .  This has the added value
     * of initializing/allocating the display private 
     */
    
    if ( dpy == NULL ) {
	return GLX_NO_EXTENSION;
    }

    *ppriv = __glXInitialize(dpy);
    if ( *ppriv == NULL ) {
	return GLX_NO_EXTENSION;
    }

    /* Check screen number to see if its valid */
    if ((scrn < 0) || (scrn >= ScreenCount(dpy))) {
	return GLX_BAD_SCREEN;
    }

    /* Check to see if the GL is supported on this screen */
    *ppsc = &((*ppriv)->screenConfigs[scrn]);
    if ( (*ppsc)->configs == NULL ) {
	/* No support for GL on this screen regardless of visual */
	return GLX_BAD_VISUAL;
    }

    return Success;
}


/**
 * Determine if a \c GLXFBConfig supplied by the application is valid.
 *
 * \param dpy     Application supplied \c Display pointer.
 * \param config  Application supplied \c GLXFBConfig.
 *
 * \returns If the \c GLXFBConfig is valid, the a pointer to the matching
 *          \c __GLcontextModes structure is returned.  Otherwise, \c NULL
 *          is returned.
 */
static __GLcontextModes *
ValidateGLXFBConfig( Display * dpy, GLXFBConfig config )
{
    __GLXdisplayPrivate * const priv = __glXInitialize(dpy);
    const unsigned num_screens = ScreenCount(dpy);
    unsigned   i;
    const __GLcontextModes * modes;


    if ( priv != NULL ) {
	for ( i = 0 ; i < num_screens ; i++ ) {
	    for ( modes = priv->screenConfigs[i].configs
		  ; modes != NULL
		  ; modes = modes->next ) {
		if ( modes == (__GLcontextModes *) config ) {
		    return (__GLcontextModes *) config;
		}
	    }
	}
    }

    return NULL;
}


/**
 * \todo It should be possible to move the allocate of \c client_state_private
 * later in the function for direct-rendering contexts.  Direct-rendering
 * contexts don't need to track client state, so they don't need that memory
 * at all.
 * 
 * \todo Eliminate \c __glXInitVertexArrayState.  Replace it with a new
 * function called \c __glXAllocateClientState that allocates the memory and
 * does all the initialization (including the pixel pack / unpack).
 */
static
GLXContext AllocateGLXContext( Display *dpy )
{
     GLXContext gc;
     int bufSize;
     CARD8 opcode;
    __GLXattribute *state;

    if (!dpy)
        return NULL;

    opcode = __glXSetupForCommand(dpy);
    if (!opcode) {
	return NULL;
    }

    /* Allocate our context record */
    gc = (GLXContext) Xmalloc(sizeof(struct __GLXcontextRec));
    if (!gc) {
	/* Out of memory */
	return NULL;
    }
    memset(gc, 0, sizeof(struct __GLXcontextRec));

    state = Xmalloc(sizeof(struct __GLXattributeRec));
    if (state == NULL) {
	/* Out of memory */
	Xfree(gc);
	return NULL;
    }
    gc->client_state_private = state;
    memset(gc->client_state_private, 0, sizeof(struct __GLXattributeRec));
    state->NoDrawArraysProtocol = (getenv("LIBGL_NO_DRAWARRAYS") != NULL);

    /*
    ** Create a temporary buffer to hold GLX rendering commands.  The size
    ** of the buffer is selected so that the maximum number of GLX rendering
    ** commands can fit in a single X packet and still have room in the X
    ** packet for the GLXRenderReq header.
    */

    bufSize = (XMaxRequestSize(dpy) * 4) - sz_xGLXRenderReq;
    gc->buf = (GLubyte *) Xmalloc(bufSize);
    if (!gc->buf) {
	Xfree(gc->client_state_private);
	Xfree(gc);
	return NULL;
    }
    gc->bufSize = bufSize;

    /* Fill in the new context */
    gc->renderMode = GL_RENDER;

    state->storePack.alignment = 4;
    state->storeUnpack.alignment = 4;

    gc->attributes.stackPointer = &gc->attributes.stack[0];

    /*
    ** PERFORMANCE NOTE: A mode dependent fill image can speed things up.
    ** Other code uses the fastImageUnpack bit, but it is never set
    ** to GL_TRUE.
    */
    gc->fastImageUnpack = GL_FALSE;
    gc->fillImage = __glFillImage;
    gc->pc = gc->buf;
    gc->bufEnd = gc->buf + bufSize;
    gc->isDirect = GL_FALSE;
    if (__glXDebug) {
	/*
	** Set limit register so that there will be one command per packet
	*/
	gc->limit = gc->buf;
    } else {
	gc->limit = gc->buf + bufSize - __GLX_BUFFER_LIMIT_SIZE;
    }
    gc->createDpy = dpy;
    gc->majorOpcode = opcode;

    /*
    ** Constrain the maximum drawing command size allowed to be
    ** transfered using the X_GLXRender protocol request.  First
    ** constrain by a software limit, then constrain by the protocl
    ** limit.
    */
    if (bufSize > __GLX_RENDER_CMD_SIZE_LIMIT) {
        bufSize = __GLX_RENDER_CMD_SIZE_LIMIT;
    }
    if (bufSize > __GLX_MAX_RENDER_CMD_SIZE) {
        bufSize = __GLX_MAX_RENDER_CMD_SIZE;
    }
    gc->maxSmallRenderCommandSize = bufSize;
    return gc;
}


/**
 * Create a new context.  Exactly one of \c vis and \c fbconfig should be
 * non-NULL.
 * 
 * \param use_glx_1_3  For FBConfigs, should GLX 1.3 protocol or
 *                     SGIX_fbconfig protocol be used?
 * \param renderType   For FBConfigs, what is the rendering type?
 */

static GLXContext
CreateContext(Display *dpy, XVisualInfo *vis,
	      const __GLcontextModes * const fbconfig,
	      GLXContext shareList,
	      Bool allowDirect, GLXContextID contextID,
	      Bool use_glx_1_3, int renderType)
{
    GLXContext gc;
#ifdef GLX_DIRECT_RENDERING
    int screen = (fbconfig == NULL) ? vis->screen : fbconfig->screen;
    __GLXscreenConfigs * const psc = GetGLXScreenConfigs(dpy, screen);
#endif

    if ( dpy == NULL )
       return NULL;

    gc = AllocateGLXContext(dpy);
    if (!gc)
	return NULL;

    if (None == contextID) {
	if ( (vis == NULL) && (fbconfig == NULL) )
	    return NULL;

#ifdef GLX_DIRECT_RENDERING
	if (allowDirect && psc->driScreen) {
	    const __GLcontextModes * mode;

	    if (fbconfig == NULL) {
		mode = _gl_context_modes_find_visual(psc->visuals, vis->visualid);
		if (mode == NULL) {
		   xError error;

		   error.errorCode = BadValue;
		   error.resourceID = vis->visualid;
		   error.sequenceNumber = dpy->request;
		   error.type = X_Error;
		   error.majorCode = gc->majorOpcode;
		   error.minorCode = X_GLXCreateContext;
		   _XError(dpy, &error);
		   return None;
		}
	    }
	    else {
		mode = fbconfig;
	    }

	    gc->driContext = psc->driScreen->createContext(psc, mode, gc,
							   shareList,
							   renderType);
	    if (gc->driContext != NULL) {
		gc->screen = mode->screen;
		gc->psc = psc;
		gc->mode = mode;
		gc->isDirect = GL_TRUE;
	    }
	}
#endif

	LockDisplay(dpy);
	if ( fbconfig == NULL ) {
	    xGLXCreateContextReq *req;

	    /* Send the glXCreateContext request */
	    GetReq(GLXCreateContext,req);
	    req->reqType = gc->majorOpcode;
	    req->glxCode = X_GLXCreateContext;
	    req->context = gc->xid = XAllocID(dpy);
	    req->visual = vis->visualid;
	    req->screen = vis->screen;
	    req->shareList = shareList ? shareList->xid : None;
#ifdef GLX_DIRECT_RENDERING
	    req->isDirect = gc->driContext != NULL;
#else
	    req->isDirect = 0;
#endif
	}
	else if ( use_glx_1_3 ) {
	    xGLXCreateNewContextReq *req;

	    /* Send the glXCreateNewContext request */
	    GetReq(GLXCreateNewContext,req);
	    req->reqType = gc->majorOpcode;
	    req->glxCode = X_GLXCreateNewContext;
	    req->context = gc->xid = XAllocID(dpy);
	    req->fbconfig = fbconfig->fbconfigID;
	    req->screen = fbconfig->screen;
	    req->renderType = renderType;
	    req->shareList = shareList ? shareList->xid : None;
#ifdef GLX_DIRECT_RENDERING
	    req->isDirect = gc->driContext != NULL;
#else
	    req->isDirect = 0;
#endif
	}
	else {
	    xGLXVendorPrivateWithReplyReq *vpreq;
	    xGLXCreateContextWithConfigSGIXReq *req;

	    /* Send the glXCreateNewContext request */
	    GetReqExtra(GLXVendorPrivateWithReply,
			sz_xGLXCreateContextWithConfigSGIXReq-sz_xGLXVendorPrivateWithReplyReq,vpreq);
	    req = (xGLXCreateContextWithConfigSGIXReq *)vpreq;
	    req->reqType = gc->majorOpcode;
	    req->glxCode = X_GLXVendorPrivateWithReply;
	    req->vendorCode = X_GLXvop_CreateContextWithConfigSGIX;
	    req->context = gc->xid = XAllocID(dpy);
	    req->fbconfig = fbconfig->fbconfigID;
	    req->screen = fbconfig->screen;
	    req->renderType = renderType;
	    req->shareList = shareList ? shareList->xid : None;
#ifdef GLX_DIRECT_RENDERING
	    req->isDirect = gc->driContext != NULL;
#else
	    req->isDirect = 0;
#endif
	}

	UnlockDisplay(dpy);
	SyncHandle();
	gc->imported = GL_FALSE;
    }
    else {
	gc->xid = contextID;
	gc->imported = GL_TRUE;
    }

    return gc;
}

PUBLIC GLXContext glXCreateContext(Display *dpy, XVisualInfo *vis,
				   GLXContext shareList, Bool allowDirect)
{
   return CreateContext(dpy, vis, NULL, shareList, allowDirect, None,
			False, 0);
}

_X_HIDDEN void __glXFreeContext(__GLXcontext *gc)
{
    if (gc->vendor) XFree((char *) gc->vendor);
    if (gc->renderer) XFree((char *) gc->renderer);
    if (gc->version) XFree((char *) gc->version);
    if (gc->extensions) XFree((char *) gc->extensions);
    __glFreeAttributeState(gc);
    XFree((char *) gc->buf);