glxext.c

mesa-6.5-minigui源码

    if (cx == &dummyContext) {
	return NULL;
    } else {
	return cx;
    }
}

GLXDrawable glXGetCurrentDrawable(void)
{
    GLXContext gc = __glXGetCurrentContext();
    return gc->currentDrawable;
}


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

#ifdef GLX_DIRECT_RENDERING
/* Return the DRI per screen structure */
__DRIscreen *__glXFindDRIScreen(__DRInativeDisplay *dpy, int scrn)
{
    __DRIscreen *pDRIScreen = NULL;
    XExtDisplayInfo *info = __glXFindDisplay(dpy);
    XExtData **privList, *found;
    __GLXdisplayPrivate *dpyPriv;
    XEDataObject dataObj;

    __glXLock();
    dataObj.display = dpy;
    privList = XEHeadOfExtensionList(dataObj);
    found = XFindOnExtensionList(privList, info->codes->extension);
    __glXUnlock();

    if (found) {
	dpyPriv = (__GLXdisplayPrivate *)found->private_data;
	pDRIScreen = &dpyPriv->screenConfigs[scrn].driScreen;
    }

    return pDRIScreen;
}
#endif

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

static Bool SendMakeCurrentRequest( Display *dpy, CARD8 opcode,
    GLXContextID gc, GLXContextTag old_gc, GLXDrawable draw, GLXDrawable read,
    xGLXMakeCurrentReply * reply );

/**
 * Sends a GLX protocol message to the specified display to make the context
 * and the drawables current.
 *
 * \param dpy     Display to send the message to.
 * \param opcode  Major opcode value for the display.
 * \param gc_id   Context tag for the context to be made current.
 * \param draw    Drawable ID for the "draw" drawable.
 * \param read    Drawable ID for the "read" drawable.
 * \param reply   Space to store the X-server's reply.
 *
 * \warning
 * This function assumes that \c dpy is locked with \c LockDisplay on entry.
 */
static Bool SendMakeCurrentRequest( Display *dpy, CARD8 opcode,
				    GLXContextID gc_id, GLXContextTag gc_tag,
				    GLXDrawable draw, GLXDrawable read,
				    xGLXMakeCurrentReply * reply )
{
    if ( draw == read ) {
	xGLXMakeCurrentReq *req;

	GetReq(GLXMakeCurrent,req);
	req->reqType = opcode;
	req->glxCode = X_GLXMakeCurrent;
	req->drawable = draw;
	req->context = gc_id;
	req->oldContextTag = gc_tag;
    }
    else {
	__GLXdisplayPrivate *priv = __glXInitialize(dpy);

	/* If the server can support the GLX 1.3 version, we should
	 * perfer that.  Not only that, some servers support GLX 1.3 but
	 * not the SGI extension.
	 */

	if ( (priv->majorVersion > 1) || (priv->minorVersion >= 3) ) {
	    xGLXMakeContextCurrentReq *req;

	    GetReq(GLXMakeContextCurrent,req);
	    req->reqType = opcode;
	    req->glxCode = X_GLXMakeContextCurrent;
	    req->drawable = draw;
	    req->readdrawable = read;
	    req->context = gc_id;
	    req->oldContextTag = gc_tag;
	}
	else {
	    xGLXVendorPrivateWithReplyReq *vpreq;
	    xGLXMakeCurrentReadSGIReq *req;

	    GetReqExtra(GLXVendorPrivateWithReply,
			sz_xGLXMakeCurrentReadSGIReq-sz_xGLXVendorPrivateWithReplyReq,vpreq);
	    req = (xGLXMakeCurrentReadSGIReq *)vpreq;
	    req->reqType = opcode;
	    req->glxCode = X_GLXVendorPrivateWithReply;
	    req->vendorCode = X_GLXvop_MakeCurrentReadSGI;
	    req->drawable = draw;
	    req->readable = read;
	    req->context = gc_id;
	    req->oldContextTag = gc_tag;
	}
    }

    return _XReply(dpy, (xReply*) reply, 0, False);
}


#ifdef GLX_DIRECT_RENDERING
static Bool BindContextWrapper( Display *dpy, GLXContext gc,
				GLXDrawable draw, GLXDrawable read )
{
    return (*gc->driContext.bindContext)(dpy, gc->screen, draw, read,
					 & gc->driContext);
}


static Bool UnbindContextWrapper( GLXContext gc )
{
    return (*gc->driContext.unbindContext)(gc->currentDpy, gc->screen, 
					   gc->currentDrawable,
					   gc->currentReadable,
					   & gc->driContext );
}
#endif /* GLX_DIRECT_RENDERING */


/*
** Make a particular context current.
** NOTE: this is in this file so that it can access dummyContext.
*/
USED static Bool MakeContextCurrent(Display *dpy, GLXDrawable draw,
                                    GLXDrawable read, GLXContext gc)
{
    xGLXMakeCurrentReply reply;
    GLXContext oldGC;
    CARD8 opcode, oldOpcode;
    Bool sentRequestToOldDpy = False;
    Bool bindReturnValue = True;

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

    /*
    ** Make sure that the new context has a nonzero ID.  In the request,
    ** a zero context ID is used only to mean that we bind to no current
    ** context.
    */
    if ((gc != NULL) && (gc->xid == None)) {
	return GL_FALSE;
    }

    oldGC = __glXGetCurrentContext();
    oldOpcode = (gc == oldGC) ? opcode : __glXSetupForCommand(dpy);
    if (!oldOpcode) {
	return GL_FALSE;
    }

    if ((dpy != oldGC->currentDpy || (gc && gc->isDirect)) &&
	!oldGC->isDirect && oldGC != &dummyContext) {
	/*
	** We are either switching from one dpy to another and have to
	** send a request to the previous dpy to unbind the previous
	** context, or we are switching away from a indirect context to
	** a direct context and have to send a request to the dpy to
	** unbind the previous context.
	*/
	sentRequestToOldDpy = True;
        LockDisplay(oldGC->currentDpy);
	if ( ! SendMakeCurrentRequest( oldGC->currentDpy, oldOpcode, None,
				       oldGC->currentContextTag, None, None,
				       &reply ) ) {
	    /* The make current failed.  Just return GL_FALSE. */
	    UnlockDisplay(oldGC->currentDpy);
	    SyncHandle();
	    return GL_FALSE;
	}

	oldGC->currentContextTag = 0;
    }

    _glapi_check_multithread();

#ifdef GLX_DIRECT_RENDERING
    /* Unbind the old direct rendering context */
    if (oldGC->isDirect) {
	if (oldGC->driContext.private) {
	    if (! UnbindContextWrapper( oldGC )) {
		/* The make current failed.  Just return GL_FALSE. */
		return GL_FALSE;
	    }
	}
	oldGC->currentContextTag = 0;
    }

    /* Bind the direct rendering context to the drawable */
    if (gc && gc->isDirect) {
	if (gc->driContext.private) {
	    bindReturnValue = BindContextWrapper( dpy, gc, draw, read );
	}
    } else {
#endif
	/* Send a glXMakeCurrent request to bind the new context. */
	LockDisplay(dpy);

	bindReturnValue = SendMakeCurrentRequest( dpy, opcode, 
						  gc ? gc->xid : None,
						  oldGC->currentContextTag,
						  draw, read, &reply );
	UnlockDisplay(dpy);
#ifdef GLX_DIRECT_RENDERING
    }
#endif


    if (!bindReturnValue) {
	/* The make current failed. */
	if (gc && !gc->isDirect) {
	    SyncHandle();
	}

#ifdef GLX_DIRECT_RENDERING
	/* If the old context was direct rendering, then re-bind to it. */
	if (oldGC->isDirect) {
	    if (oldGC->driContext.private) {
		if (! BindContextWrapper( oldGC->currentDpy, oldGC,
					  oldGC->currentDrawable,
					  oldGC->currentReadable )) {
		    /*
		    ** The request failed; this cannot happen with the
		    ** current API.  If in the future the API is
		    ** extended to allow context sharing between
		    ** clients, then this may fail (because another
		    ** client may have grabbed the context); in that
		    ** case, we cannot undo the previous request, and
		    ** cannot adhere to the "no-op" behavior.
		    */
		}
	    }
	} else
#endif
	/*
	** If we had just sent a request to a previous dpy, we have to
	** undo that request (because if a command fails, it should act
	** like a no-op) by making current to the previous context and
	** drawable.
	*/
	if (sentRequestToOldDpy) {
	    if ( !SendMakeCurrentRequest( oldGC->currentDpy, oldOpcode,
					  oldGC->xid, 0, 
					  oldGC->currentDrawable,
					  oldGC->currentReadable, &reply ) ) {
		UnlockDisplay(oldGC->currentDpy);
		SyncHandle();
		/*
		** The request failed; this cannot happen with the
		** current API.  If in the future the API is extended to
		** allow context sharing between clients, then this may
		** fail (because another client may have grabbed the
		** context); in that case, we cannot undo the previous
		** request, and cannot adhere to the "no-op" behavior.
		*/
	    }
            else {
		UnlockDisplay(oldGC->currentDpy);
            }
	    oldGC->currentContextTag = reply.contextTag;
	}
	return GL_FALSE;
    }

    /* Update our notion of what is current */
    __glXLock();
    if (gc == oldGC) {
	/*
	** Even though the contexts are the same the drawable might have
	** changed.  Note that gc cannot be the dummy, and that oldGC
	** cannot be NULL, therefore if they are the same, gc is not
	** NULL and not the dummy.
	*/
	gc->currentDrawable = draw;
	gc->currentReadable = read;
    } else {
	if (oldGC != &dummyContext) {
	    /* Old current context is no longer current to anybody */
	    oldGC->currentDpy = 0;
	    oldGC->currentDrawable = None;
	    oldGC->currentReadable = None;
	    oldGC->currentContextTag = 0;

	    if (oldGC->xid == None) {
		/* 
		** We are switching away from a context that was
		** previously destroyed, so we need to free the memory
		** for the old handle.
		*/
#ifdef GLX_DIRECT_RENDERING
		/* Destroy the old direct rendering context */
		if (oldGC->isDirect) {
		    if (oldGC->driContext.private) {
			(*oldGC->driContext.destroyContext)
			    (dpy, oldGC->screen, oldGC->driContext.private);
			oldGC->driContext.private = NULL;
		    }
		}
#endif
		__glXFreeContext(oldGC);
	    }
	}
	if (gc) {
	    __glXSetCurrentContext(gc);
#ifdef GLX_DIRECT_RENDERING
            if (!gc->isDirect) {
               if (!IndirectAPI)
                  IndirectAPI = __glXNewIndirectAPI();
               _glapi_set_dispatch(IndirectAPI);
# ifdef GLX_USE_APPLEGL
               do {
                   extern void XAppleDRIUseIndirectDispatch(void);
                   XAppleDRIUseIndirectDispatch();
               } while (0);
# endif
            }
#else
            /* if not direct rendering, always need indirect dispatch */
            if (!IndirectAPI)
               IndirectAPI = __glXNewIndirectAPI();
            _glapi_set_dispatch(IndirectAPI);
#endif
	    gc->currentDpy = dpy;
	    gc->currentDrawable = draw;
	    gc->currentReadable = read;

	    if ( ! gc->isDirect ) {
		__GLXattribute * state = (__GLXattribute *)(gc->client_state_private);

		gc->currentContextTag = reply.contextTag;
		if ( state->array_state == NULL ) {
		    (void) glGetString( GL_EXTENSIONS );
		    (void) glGetString( GL_VERSION );
		    __glXInitVertexArrayState(gc);
		}
	    }
	    else {
		gc->currentContextTag = -1;
	    }
	} else {
	    __glXSetCurrentContext(&dummyContext);
#ifdef GLX_DIRECT_RENDERING
            _glapi_set_dispatch(NULL);  /* no-op functions */
#endif
	}
    }
    __glXUnlock();
    return GL_TRUE;
}


PUBLIC Bool glXMakeCurrent(Display *dpy, GLXDrawable draw, GLXContext gc)
{
    return MakeContextCurrent( dpy, draw, draw, gc );
}

PUBLIC GLX_ALIAS(Bool, glXMakeCurrentReadSGI,
	  (Display *dpy, GLXDrawable d, GLXDrawable r, GLXContext ctx),
	  (dpy, d, r, ctx), MakeContextCurrent)

PUBLIC GLX_ALIAS(Bool, glXMakeContextCurrent,
	  (Display *dpy, GLXDrawable d, GLXDrawable r, GLXContext ctx),
	  (dpy, d, r, ctx), MakeContextCurrent)


#ifdef DEBUG
void __glXDumpDrawBuffer(__GLXcontext *ctx)
{
    GLubyte *p = ctx->buf;
    GLubyte *end = ctx->pc;
    GLushort opcode, length;

    while (p < end) {
	/* Fetch opcode */
	opcode = *((GLushort*) p);
	length = *((GLushort*) (p + 2));
	printf("%2x: %5d: ", opcode, length);
	length -= 4;
	p += 4;
	while (length > 0) {
	    printf("%08x ", *((unsigned *) p));
	    p += 4;
	    length -= 4;
	}
	printf("\n");
    }	    
}
#endif

#ifdef  USE_SPARC_ASM
/*
 * Used only when we are sparc, using sparc assembler.
 *
 */

static void
_glx_mesa_init_sparc_glapi_relocs(void)
{
	unsigned int *insn_ptr, *end_ptr;
	unsigned long disp_addr;

	insn_ptr = &_mesa_sparc_glapi_begin;
	end_ptr = &_mesa_sparc_glapi_end;
	disp_addr = (unsigned long) &_glapi_Dispatch;

	/*
         * Verbatim from Mesa sparc.c.  It's needed because there doesn't
         * seem to be a better way to do this:
         *
         * UNCONDITIONAL_JUMP ( (*_glapi_Dispatch) + entry_offset )
         *
         * This code is patching in the ADDRESS of the pointer to the
         * dispatch table.  Hence, it must be called exactly once, because
         * that address is not going to change.
         *
         * What it points to can change, but Mesa (and hence, we) assume
         * that there is only one pointer.
         *
	 */
	while (insn_ptr < end_ptr) {
#if ( defined(__sparc_v9__) && ( !defined(__linux__) || defined(__linux_64__) ) )	
/*
	This code patches for 64-bit addresses.  This had better
	not happen for Sparc/Linux, no matter what architecture we
	are building for.  So, don't do this.

        The 'defined(__linux_64__)' is used here as a placeholder for
        when we do do 64-bit usermode on sparc linux.
	*/
		insn_ptr[0] |= (disp_addr >> (32 + 10));
		insn_ptr[1] |= ((disp_addr & 0xffffffff) >> 10);
		__glapi_sparc_icache_flush(&insn_ptr[0]);
		insn_ptr[2] |= ((disp_addr >> 32) & ((1 << 10) - 1));
		insn_ptr[3] |= (disp_addr & ((1 << 10) - 1));
		__glapi_sparc_icache_flush(&insn_ptr[2]);
		insn_ptr += 11;
#else
		insn_ptr[0] |= (disp_addr >> 10);
		insn_ptr[1] |= (disp_addr & ((1 << 10) - 1));
		__glapi_sparc_icache_flush(&insn_ptr[0]);
		insn_ptr += 5;
#endif
	}
}
#endif  /* sparc ASM in use */