From f262004e1339f7265c3b669394c830b0bc20841b Mon Sep 17 00:00:00 2001
From: FunkyFr3sh <cc.red.alert.1@googlemail.com>
Date: Tue, 1 Jun 2021 17:35:00 +0200
Subject: [PATCH] add patch.h for testing

---
 inc/patch.h | 55 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)
 create mode 100644 inc/patch.h

diff --git a/inc/patch.h b/inc/patch.h
new file mode 100644
index 0000000..b8716ef
--- /dev/null
+++ b/inc/patch.h
@@ -0,0 +1,55 @@
+#ifndef PATCH_H 
+#define PATCH_H 
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+static inline PROC patch_call(char *src, char *dst)
+{
+    DWORD op = PAGE_EXECUTE_READ;
+    VirtualProtect(src, 5, PAGE_EXECUTE_READWRITE, &op);
+    src[0] = 0xE8;
+    DWORD org = *((DWORD *)(&src[1]));
+    *((DWORD *)(&src[1])) = dst - src - 5;
+    VirtualProtect(src, 5, op, &op);
+    return (PROC)(src + 5 + org);
+}
+
+static inline void patch_ljmp(char *src, char *dst)
+{
+    DWORD op = PAGE_EXECUTE_READ;
+    VirtualProtect(src, 5, PAGE_EXECUTE_READWRITE, &op);
+    src[0] = 0xE9;
+    *((DWORD *)(&src[1])) = dst - src - 5;
+    VirtualProtect(src, 5, op, &op);
+}
+
+static inline void patch_clear(char *start, char value, char *end)
+{
+    DWORD op = PAGE_EXECUTE_READ;
+    VirtualProtect(start, end - start, PAGE_EXECUTE_READWRITE, &op);
+    memset(start, value, end - start);
+    VirtualProtect(start, end - start, op, &op);
+}
+
+static inline DWORD patch_setdword(DWORD *dst, DWORD value)
+{
+    DWORD op = PAGE_EXECUTE_READ;
+    VirtualProtect(dst, sizeof(DWORD), PAGE_EXECUTE_READWRITE, &op);
+    DWORD org = *dst;
+    *dst = value; 
+    VirtualProtect(dst, sizeof(DWORD), op, &op);
+    return org;
+}
+
+static inline void patch_setbytes(char *dst, char *buf, size_t size)
+{
+    DWORD op = PAGE_EXECUTE_READ;
+    VirtualProtect(dst, size, PAGE_EXECUTE_READWRITE, &op);
+    memcpy(dst, buf, size);
+    VirtualProtect(dst, size, op, &op);
+}
+
+#define PATCH_SET(a,b) patch_setbytes(a,b,sizeof(b)-1)
+
+#endif