memcpy, memset; small fixes

2 files changed, 57 insertions, 16 deletions

diff --git a/kernel/src/libk/stdio.c b/kernel/src/libk/stdio.c
index be75b73..da5d839 100644
--- a/kernel/src/libk/stdio.c
+++ b/kernel/src/libk/stdio.c
@@ -5,32 +5,32 @@
 #include <libk/string.h>
 #include <graphics.h>
 
-int32_t x;
-int32_t y;
+uint32_t curr_x;
+uint32_t curr_y;
 
 inline void print_char(char c)
 {
+	if (curr_x * 8 >= main_fb.width) {
+		curr_x = 0;
+		curr_y++;
+	}
+	if (curr_y * 16 >= main_fb.height) {
+		curr_x = 0;
+		curr_y = 0;
+	}
 	if (c == '\n') {
-		x = 0;
-		y++;
+		curr_x = 0;
+		curr_y++;
 		return;
 	}
 	if (c == '\b') {
-		if (x != 0) {
-			x--;
+		if (curr_x != 0) {
+			curr_x--;
 		}
 		return;
 	}
-	if (x * 8 >= (int32_t)main_fb.width) {
-		x = 0;
-		y++;
-	}
-	if (y * 16 >= (int32_t)main_fb.height) {
-		x = 0;
-		y = 0;
-	}
-	fb_draw_character(main_fb, c, x * 8, y * 16, WHITE, BLACK);
-	x++;
+	fb_draw_character(main_fb, c, (int32_t)curr_x * 8, (int32_t)curr_y * 16, WHITE, BLACK);
+	curr_x++;
 }
 
 inline void print_string(const char* s)
diff --git a/kernel/src/libk/string.c b/kernel/src/libk/string.c
index 6d7ab69..be37ba9 100644
--- a/kernel/src/libk/string.c
+++ b/kernel/src/libk/string.c
@@ -67,3 +67,44 @@ void itoh(uint64_t num, char* s)
 	s[i] = '\0';
 	strrev(s);
 }
+
+void memcpy(const void* destptr, const void* srcptr, size_t n)
+{
+	uint8_t* dest = (uint8_t*)destptr;
+	const uint8_t* src = (const uint8_t*)srcptr;
+
+	for(size_t i = 0; i < n; i++) {
+		dest[i] = src[i];
+	}
+}
+
+void memset(const void* destptr, uint8_t value, size_t n)
+{
+	uint8_t* dest = (uint8_t*)destptr;
+
+	for (size_t i = 0; i < n; i++) {
+		dest[i] = value;
+	}
+}
+
+int32_t memcmp(const void* aptr, const void* bptr)
+{
+	const uint8_t* a = (const uint8_t*)aptr;
+	const uint8_t* b = (const uint8_t*)bptr;
+
+	const size_t len_a = strlen((char*)a);
+	const size_t len_b = strlen((char*)b);
+
+	for (size_t i = 0; i < len_a && i < len_b; i++) {
+		if (a[i] != b[i])
+			return a[i] - b[i];
+	}
+
+	if (len_a < len_b) {
+		return -1;
+	}
+	if (len_a > len_b) {
+		return 1;
+	}
+	return 0;
+}