initial commit -- v1 code

src/detour.cpp

@@ -0,0 +1,69 @@
+#include "detour.h"
+
+#include "common.h"
+#include "gameconfig.h"
+#include "overrides.h"
+#include "playerslot.h"
+
+extern CGameConfig* g_gameConfig;
+extern bool g_enabled;
+extern bool g_armed;
+
+using SendSnapshotFn = void (*)(void*, void*);
+static SendSnapshotFn g_sendSnapshot = nullptr;
+static funchook_t* g_hook = nullptr;
+
+static CPlayerSlot SlotFromClient(void* client)
+{
+	int offset = g_gameConfig ? g_gameConfig->GetOffset("CServerSideClient_Slot") : -1;
+	if (offset < 0)
+		return CPlayerSlot(-1);
+	return *reinterpret_cast<CPlayerSlot*>(reinterpret_cast<uint8_t*>(client) + offset);
+}
+
+static void Detour_SendSnapshot(void* client, void* snapshot)
+{
+	if (!g_enabled || !g_armed || !client || g_overrides.Empty())
+	{
+		g_sendSnapshot(client, snapshot);
+		return;
+	}
+
+	CPlayerSlot slot = SlotFromClient(client);
+	auto applied = g_overrides.ApplyForRecipient(slot);
+	g_sendSnapshot(client, snapshot);
+	g_overrides.Restore(applied);
+}
+
+bool InitSnapshotDetour(CGameConfig* config)
+{
+	void* target = config->ResolveSignature("CServerSideClient_SendSnapshot");
+	if (!target)
+	{
+		SPWarning("CServerSideClient_SendSnapshot signature missing; snapshot hook disabled\n");
+		return true;
+	}
+
+	g_sendSnapshot = reinterpret_cast<SendSnapshotFn>(target);
+	g_hook = funchook_create();
+	if (!g_hook)
+		return false;
+
+	if (funchook_prepare(g_hook, reinterpret_cast<void**>(&g_sendSnapshot), reinterpret_cast<void*>(Detour_SendSnapshot)) != 0)
+		return false;
+	if (funchook_install(g_hook, 0) != 0)
+		return false;
+
+	SPMessage("detoured CServerSideClient_SendSnapshot at %p\n", target);
+	return true;
+}
+
+void ShutdownSnapshotDetour()
+{
+	if (!g_hook)
+		return;
+	funchook_uninstall(g_hook, 0);
+	funchook_destroy(g_hook);
+	g_hook = nullptr;
+	g_sendSnapshot = nullptr;
+}