glx: Initial implementation of glXCreateContextAttribsARB

[mesa.git] / src / glx / create_context.c

diff --git a/src/glx/create_context.c b/src/glx/create_context.c
new file mode 100644 (file)
index 0000000..41f0805
--- /dev/null
+++ b/src/glx/create_context.c
@@ -0,0 +1,117 @@
+/*
+ * Copyright © 2011 Intel Corporation
+ *
+ * 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 and this permission notice (including the next
+ * paragraph) 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
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ */
+
+#include <limits.h>
+#include "glxclient.h"
+#include "glx_error.h"
+#include <xcb/glx.h>
+#include <X11/Xlib-xcb.h>
+
+#include <assert.h>
+
+#if INT_MAX != 2147483647
+#error This code requires sizeof(uint32_t) == sizeof(int).
+#endif
+
+_X_HIDDEN GLXContext
+glXCreateContextAttribsARB(Display *dpy, GLXFBConfig config,
+                          GLXContext share_context, Bool direct,
+                          const int *attrib_list)
+{
+   xcb_connection_t *const c = XGetXCBConnection(dpy);
+   struct glx_config *const cfg = (struct glx_config *) config;
+   struct glx_context *const share = (struct glx_context *) share_context;
+   struct glx_context *gc = NULL;
+   unsigned num_attribs = 0;
+   struct glx_screen *psc;
+   xcb_generic_error_t *err;
+   xcb_void_cookie_t cookie;
+   unsigned dummy_err = 0;
+
+
+   if (dpy == NULL || cfg == NULL)
+      return NULL;
+
+   /* This means that either the caller passed the wrong display pointer or
+    * one of the internal GLX data structures (probably the fbconfig) has an
+    * error.  There is nothing sensible to do, so return an error.
+    */
+   psc = GetGLXScreenConfigs(dpy, cfg->screen);
+   if (psc == NULL)
+      return NULL;
+
+   assert(cfg->screen == psc->scr);
+
+   /* Count the number of attributes specified by the application.  All
+    * attributes appear in pairs, except the terminating None.
+    */
+   if (attrib_list != NULL) {
+      for (/* empty */; attrib_list[num_attribs * 2] != 0; num_attribs++)
+        /* empty */ ;
+   }
+
+   if (direct && psc->vtable->create_context_attribs) {
+      /* GLX drops the error returned by the driver.  The expectation is that
+       * an error will also be returned by the server.  The server's error
+       * will be delivered to the application.
+       */
+      gc = psc->vtable->create_context_attribs(psc, cfg, share, num_attribs,
+                                              (const uint32_t *) attrib_list,
+                                              &dummy_err);
+   }
+
+   if (gc == NULL)
+      gc = indirect_create_context(psc, cfg, share, 0);
+
+   gc->xid = xcb_generate_id(c);
+   gc->share_xid = (share != NULL) ? share->xid : 0;
+
+   /* The manual pages for glXCreateContext and glXCreateNewContext say:
+    *
+    *     "NULL is returned if execution fails on the client side."
+    *
+    * If the server generates an error, the application is supposed to catch
+    * the protocol error and handle it.  Part of handling the error is freeing
+    * the possibly non-NULL value returned by this function.
+    */
+   cookie =
+      xcb_glx_create_context_attribs_arb_checked(c,
+                                                gc->xid,
+                                                cfg->fbconfigID,
+                                                cfg->screen,
+                                                gc->share_xid,
+                                                gc->isDirect,
+                                                num_attribs,
+                                                (const uint32_t *)
+                                                attrib_list);
+   err = xcb_request_check(c, cookie);
+   if (err != NULL) {
+      gc->vtable->destroy(gc);
+      gc = NULL;
+
+      __glXSendErrorForXcb(dpy, err);
+      free(err);
+   }
+
+   return (GLXContext) gc;
+}