Updated some broken projects, cleaned up example code, and remove old artifacts

Chapter8_ControlFlow/NOPExample.cpp

@@ -0,0 +1,85 @@
+#include "main.h"
+
+// this is the simulated list of creatures in the game
+std::vector<_creature> creatures;
+int creaturesDrawn = 0;
+
+// this is the simulated function to draw creature names
+void drawHealthBar(int healthbar) 
+{
+	creaturesDrawn++; // make a note that we drew it
+	Sleep(healthbar); // just an example, we're not really doing anything
+}
+
+// this is the function where we place the NOP.
+void drawCreatureHealthBarExample()
+{
+	for (int i = 0; i < creatures.size(); i++) {
+		auto c = creatures[i];
+		if (c.isEnemy && c.isCloaked)
+		{
+			// our NOP is esentially going to remove this continue statement,
+			// which will be a JUMP that evades the drawHealthBar car
+			continue;
+		}
+		drawHealthBar(c.healthBar);
+	}
+}
+
+// this is the function that actually does the NOP
+template<int SIZE>
+void writeNop(DWORD address)
+{
+	auto oldProtection = protectMemory<BYTE[SIZE]>(address, PAGE_EXECUTE_READWRITE);
+	for (int i = 0; i < SIZE; i++)
+		writeMemory<BYTE>(address + i, 0x90);
+	protectMemory<BYTE[SIZE]>(address, oldProtection);
+}
+
+
+// I cannot hard-code any addresses from within this application,
+// as they may change upon re-compile. For this reason, I'll locate
+// the address of the JMP that I want to replace programatically
+// by scanning for the 'JMP -67' statement (bytes 0xEB 0xBD)
+// somewhere within 1000 bytes of the start of the function
+DWORD getAddressForNOP(DWORD functionStart)
+{
+	auto oldProtection = protectMemory<BYTE[1000]>(functionStart, PAGE_EXECUTE_READ); // make sure memory is readable, just incase
+	auto mem = pointMemory<BYTE>(functionStart);
+
+	DWORD ret = 0;
+	for (int i = 0; i < 999; i++) {
+		if (mem[i] == 0xEB && mem[i+1] == 0xBD) {
+			ret = functionStart + i;
+			break;
+		}
+	}
+	protectMemory<BYTE[1000]>(functionStart, oldProtection); // restore old memory protection
+	return ret;
+}
+
+// This ties the entire example together
+void NOPExample()
+{
+	creaturesDrawn = 0;
+
+	// nop it
+	auto address = getAddressForNOP((DWORD)&drawCreatureHealthBarExample);
+	if (address)
+		writeNop<2>(address);
+
+	// add some make creatures
+	creatures.push_back(_creature(0, true, true));
+	creatures.push_back(_creature(0, true, false));
+	creatures.push_back(_creature(0, false, true));
+	creatures.push_back(_creature(0, false, false));
+
+	//call the function
+	drawCreatureHealthBarExample();
+
+	//check if NOP worked
+	if (creaturesDrawn == 4)
+		printf("NOP worked! Drew all creatures!\n");
+	else
+		printf("NOP failed! :( Only drew %d/4 creatures.\n", creaturesDrawn);
+}