From c601aed9f21540add494e31d631da701574cc312 Mon Sep 17 00:00:00 2001
From: Nathan Giddings <nathang567@gmail.com>
Date: Wed, 18 Nov 2020 13:36:09 -0600
Subject: [PATCH] Wrote strlen() and strcpy()

---
 src/Makefile.am |  2 +-
 src/module.cpp  |  2 +-
 src/util.cpp    | 47 ++++++++++++++++++++++++++++++++++++++++++++++-
 src/util.hpp    |  4 ++++
 4 files changed, 52 insertions(+), 3 deletions(-)

diff --git a/src/Makefile.am b/src/Makefile.am
index 52e771e..718ad10 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,5 +1,5 @@
 noinst_PROGRAMS = quark-kernel
-quark_kernel_SOURCES = startup.cpp elf.cpp tty.cpp systeminfo.cpp util.cpp memorymap.cpp pageallocator.cpp allocator.cpp scheduler.cpp
+quark_kernel_SOURCES = startup.cpp module.cpp tty.cpp systeminfo.cpp util.cpp memorymap.cpp pageallocator.cpp allocator.cpp scheduler.cpp
 quark_kernel_LDADD = -lgcc
 quark_kernel_CPPFLAGS = -ffreestanding -mgeneral-regs-only -O0 -Wall -fno-exceptions -fno-rtti -ggdb
 quark_kernel_LDFLAGS = -nostdlib
diff --git a/src/module.cpp b/src/module.cpp
index e327acf..c0a1eee 100644
--- a/src/module.cpp
+++ b/src/module.cpp
@@ -1,4 +1,4 @@
-#include "elf.hpp"
+#include "module.hpp"
 #include "util.hpp"
 
 kernel::ELF::ELF()
diff --git a/src/util.cpp b/src/util.cpp
index fe13afc..2dfa310 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -64,7 +64,7 @@ int memcmp(const void* ptr1, const void* ptr2, size_t num)
 	return 0;
 }
 
-void* memset (void* ptr, int value, size_t num)
+void* memset(void* ptr, int value, size_t num)
 {
 	uint8_t* dest = (uint8_t*) ptr;
 	uint8_t v = (uint8_t) value;
@@ -75,6 +75,51 @@ void* memset (void* ptr, int value, size_t num)
 	return ptr;
 }
 
+int strlen(const char* str)
+{
+	int i = 0;
+	while(str[i] != '\0')
+	{
+		i++;
+	}
+	return i;
+}
+
+char* strcpy(char* destination, const char* source)
+{
+	int sourceLen = strlen(source);
+	if((destination <= source) || (destination > (source + sourceLen)))
+	{
+		char* d = destination;
+		const char* s = source;
+		while(true)
+		{
+			*d = *s;
+			if(*s == '\0')
+			{
+				break;
+			}
+			else
+			{
+				s++;
+				d++;
+			}
+		}
+	}
+	else
+	{
+		char* d = destination + sourceLen;
+		const char* s = source + sourceLen;
+		do
+		{
+			*d = *s;
+			d--;
+			s--;
+		} while(d > destination);
+	}
+	return destination;
+}
+
 void __cxa_pure_virtual()
 {
     // do nothing
diff --git a/src/util.hpp b/src/util.hpp
index acf21d0..a16c112 100644
--- a/src/util.hpp
+++ b/src/util.hpp
@@ -13,4 +13,8 @@ extern "C" int memcmp(const void* ptr1, const void* ptr2, size_t num);
 
 extern "C" void* memset(void* ptr, int value, size_t num);
 
+extern "C" int strlen(const char* str);
+
+extern "C" char* strcpy(char* destination, const char* source);
+
 #endif
\ No newline at end of file