[PATCH 2/7] win32u: Implement opt-in WGL_(ARB|EXT)_extensions_string support.

[Rémi Bernon]

From: Rémi Bernon

---
 dlls/win32u/opengl.c         | 71 ++++++++++++++++++++++++++++++++++++
 include/wine/opengl_driver.h |  1 +
 2 files changed, 72 insertions(+)

diff --git a/dlls/win32u/opengl.c b/dlls/win32u/opengl.c
index ca0023ebe67..d0affa80495 100644
--- a/dlls/win32u/opengl.c
+++ b/dlls/win32u/opengl.c
@@ -23,6 +23,7 @@

#include "config.h"

+#include <assert.h>
 #include <pthread.h>
 #include <dlfcn.h>

@@ -38,6 +39,50 @@

WINE_DEFAULT_DEBUG_CHANNEL(wgl);

+static struct opengl_funcs *get_dc_funcs( HDC hdc, void *null_funcs );
+
+static BOOL has_extension( const char *list, const char *ext )
+{
+    size_t len = strlen( ext );
+    const char *cur = list;
+
+    while (cur && (cur = strstr( cur, ext )))
+    {
+        if ((!cur[len] || cur[len] == ' ') && (cur == list || cur[-1] == ' ')) return TRUE;
+        cur = strchr( cur, ' ' );
+    }
+
+    return FALSE;
+}
+
+static void dump_extensions( const char *list )
+{
+    const char *start, *end, *ptr;
+
+    for (start = end = ptr = list; ptr; ptr = strchr( ptr + 1, ' ' ))
+    {
+        if (ptr - start <= 128) end = ptr;
+        else
+        {
+            TRACE( "%.*s\n", (int)(end - start), start );
+            start = end + 1;
+        }
+    }
+
+    TRACE( "%s\n", start );
+}
+
+static void register_extension( char *list, size_t size, const char *name )
+{
+    if (!has_extension( list, name ))
+    {
+        size_t len = strlen( list );
+        assert( size - len >= strlen( name ) + 1 );
+        if (*list) strcat( list + len, " " );
+        strcat( list + len, name );
+    }
+}
+
 #ifdef SONAME_LIBOSMESA

#define OSMESA_COLOR_INDEX  GL_COLOR_INDEX
@@ -355,6 +400,20 @@ static struct opengl_funcs *osmesa_get_wgl_driver(void)
 static const struct opengl_driver_funcs nulldrv_funcs;
 static const struct opengl_driver_funcs *driver_funcs = &nulldrv_funcs;

+static char wgl_extensions[4096];
+
+static const char *win32u_wglGetExtensionsStringARB( HDC hdc )
+{
+    if (TRACE_ON(wgl)) dump_extensions( wgl_extensions );
+    return wgl_extensions;
+}
+
+static const char *win32u_wglGetExtensionsStringEXT(void)
+{
+    if (TRACE_ON(wgl)) dump_extensions( wgl_extensions );
+    return wgl_extensions;
+}
+
 static struct opengl_funcs *display_funcs;
 static struct opengl_funcs *memory_funcs;

@@ -373,6 +432,18 @@ static void display_funcs_init(void)
         ERR( "Failed to initialize the driver opengl functions, status %#x\n", status );
         return;
     }
+    if (!display_funcs) return;
+
+    if (driver_funcs->p_init_wgl_extensions)
+    {
+        strcpy( wgl_extensions, driver_funcs->p_init_wgl_extensions() );
+
+        register_extension( wgl_extensions, ARRAY_SIZE(wgl_extensions), "WGL_ARB_extensions_string" );
+        display_funcs->p_wglGetExtensionsStringARB = win32u_wglGetExtensionsStringARB;
+
+        register_extension( wgl_extensions, ARRAY_SIZE(wgl_extensions), "WGL_EXT_extensions_string" );
+        display_funcs->p_wglGetExtensionsStringEXT = win32u_wglGetExtensionsStringEXT;
+    }
 }

static struct opengl_funcs *get_dc_funcs( HDC hdc, void *null_funcs )
diff --git a/include/wine/opengl_driver.h b/include/wine/opengl_driver.h
index 34c83d6f40f..d8b2336aadd 100644
--- a/include/wine/opengl_driver.h
+++ b/include/wine/opengl_driver.h
@@ -113,6 +113,7 @@ struct opengl_funcs
 /* interface between win32u and the user drivers */
 struct opengl_driver_funcs
 {
+    const char *(*p_init_wgl_extensions)(void);
 };

#endif /* WINE_UNIX_LIB */