[Feat] (MG_Impl): add macOS CGL and NSOpenGL frontends

MobileGL/MG_Impl/DyldInterpose/DyldInterpose.cpp

@@ -0,0 +1,56 @@
+// MobileGL - MobileGL/MG_Impl/DyldInterpose/DyldInterpose.cpp
+// Copyright (c) 2025-2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+
+#include <Includes.h>
+
+#if defined(__APPLE__)
+
+#include "MG_Impl/GetProcAddress.h"
+
+#include <dlfcn.h>
+
+namespace {
+    struct DyldInterposeEntry {
+        const void* Replacement;
+        const void* Replacee;
+    };
+
+    bool IsGLProcName(const char* name) {
+        if (name == nullptr) {
+            return false;
+        }
+
+        if (strncmp(name, "CGL", 3) == 0) {
+            return true;
+        }
+
+        if (strncmp(name, "gl", 2) != 0) {
+            return false;
+        }
+
+        // Avoid stealing glfw*/glib*/glX*/global application symbols.
+        return name[2] >= 'A' && name[2] <= 'Z' && name[2] != 'X';
+    }
+
+    void* MobileGLDlsym(void* handle, const char* symbol) {
+        if (IsGLProcName(symbol)) {
+            if (void* proc = MobileGL::MG_Impl::GetProcAddress(symbol)) {
+                return proc;
+            }
+        }
+
+        return dlsym(handle, symbol);
+    }
+
+    __attribute__((used)) static const DyldInterposeEntry kMobileGLDyldInterpose[]
+        __attribute__((section("__DATA,__interpose"))) = {
+            {reinterpret_cast<const void*>(MobileGLDlsym), reinterpret_cast<const void*>(dlsym)},
+        };
+} // namespace
+
+#endif