glx: Implement the libglvnd interface.

With reference to the libglvnd branch:

https://cgit.freedesktop.org/mesa/mesa/log/?h=libglvnd

This is a squashed commit containing all of Kyle's commits, all but two
of Emil's commits (to follow), and a small fixup from myself to mark the
rest of the glX* functions as _GLX_PUBLIC so they are not exported when
building for libglvnd. I (ajax) squashed them together both for ease of
review, and because most of the changes are un-useful intermediate
states representing the evolution of glvnd's internal API.

Co-author: Emil Velikov <[email protected]>
Reviewed-by: Adam Jackson <[email protected]>

1 files changed, 75 insertions, 0 deletions

diff --git a/src/glx/glxglvnd.c b/src/glx/glxglvnd.c
new file mode 100644
index 00000000000..c7c35ca3a14
--- /dev/null
+++ b/src/glx/glxglvnd.c
@@ -0,0 +1,75 @@
+#include <string.h>
+#include <X11/Xlib.h>
+
+#include "glvnd/libglxabi.h"
+
+#include "glxglvnd.h"
+
+
+static Bool __glXGLVNDIsScreenSupported(Display *dpy, int screen)
+{
+    /* TODO: Think of a better heuristic... */
+    return True;
+}
+
+static void *__glXGLVNDGetProcAddress(const GLubyte *procName)
+{
+    return glXGetProcAddressARB(procName);
+}
+
+static int FindGLXFunction(const GLubyte *name)
+{
+    int i;
+
+    for (i = 0; i < DI_FUNCTION_COUNT; i++) {
+        if (strcmp((const char *) name, __glXDispatchTableStrings[i]) == 0)
+            return i;
+    }
+    return -1;
+}
+
+static void *__glXGLVNDGetDispatchAddress(const GLubyte *procName)
+{
+    int internalIndex = FindGLXFunction(procName);
+
+    if (internalIndex >= 0) {
+        return __glXDispatchFunctions[internalIndex];
+    }
+
+    return NULL;
+}
+
+static void __glXGLVNDSetDispatchIndex(const GLubyte *procName, int index)
+{
+    int internalIndex = FindGLXFunction(procName);
+
+    if (internalIndex >= 0)
+        __glXDispatchTableIndices[internalIndex] = index;
+}
+
+_X_EXPORT Bool __glx_Main(uint32_t version, const __GLXapiExports *exports,
+                          __GLXvendorInfo *vendor, __GLXapiImports *imports)
+{
+    static Bool initDone = False;
+
+    if (GLX_VENDOR_ABI_GET_MAJOR_VERSION(version) !=
+        GLX_VENDOR_ABI_MAJOR_VERSION ||
+        GLX_VENDOR_ABI_GET_MINOR_VERSION(version) <
+        GLX_VENDOR_ABI_MINOR_VERSION)
+        return False;
+
+    if (!initDone) {
+        initDone = True;
+        __glXGLVNDAPIExports = exports;
+
+        imports->isScreenSupported = __glXGLVNDIsScreenSupported;
+        imports->getProcAddress = __glXGLVNDGetProcAddress;
+        imports->getDispatchAddress = __glXGLVNDGetDispatchAddress;
+        imports->setDispatchIndex = __glXGLVNDSetDispatchIndex;
+        imports->notifyError = NULL;
+        imports->isPatchSupported = NULL;
+        imports->initiatePatch = NULL;
+    }
+
+    return True;
+}