Makefile

@@ -2,7 +2,7 @@ SOURCES = src/mem/heap/kheap.c src/mem/paging/vmm.c src/mem/paging/paging.c src/
 
 build:
 	rm -f *.o
-	x86_64-elf-gcc -g -c -Isrc $(SOURCES) -Wall -Wextra -std=gnu99 -nostdlib -ffreestanding -fno-stack-protector -fno-stack-check -fno-PIC -ffunction-sections -fdata-sections -mcmodel=kernel
+	x86_64-elf-gcc -g -c -Isrc $(SOURCES) -Wall -Wextra -std=gnu99 -nostdlib -ffreestanding -fno-stack-protector -fno-omit-frame-pointer -fno-stack-check -fno-PIC -ffunction-sections -fdata-sections -mcmodel=kernel
 	objcopy -O elf64-x86-64 -B i386 -I binary zap-light16.psf zap-light16.o
 	nasm -f elf64 src/idt/idt.S -o idt_stub.o
 	x86_64-elf-ld -o pepperk -T linker.ld *.o

src/io/term/term.c

@@ -26,68 +26,20 @@ uint8_t* glyphs = _binary_zap_light16_psf_start + sizeof(PSF1_Header);
 // Character cursor
 typedef struct
 {
-	unsigned int x;
+	size_t x;
-	unsigned int y;
+	size_t y;
 } Cursor;
 
-Cursor cursor = {0};
+static Cursor cursor = {0, 0};
 
-unsigned char* fb;
+static uint8_t* fb;
-
+static struct limine_framebuffer* framebuffer;
-struct limine_framebuffer* framebuffer;
 
 uint8_t lines_length[MAX_LINES];
 
-int term_init()
+static inline size_t term_max_cols(void)
 {
-	// Get framebuffer address from Limine struct
+	return framebuffer->width / FONT_WIDTH;
-	
-	if (boot_ctx.fb)
-	{
-		fb = boot_ctx.fb->address;
-		framebuffer = boot_ctx.fb;
-		DEBUG("terminal initialized, fb=0x%p (width=%u height=%u pitch=%u bpp=%u)", fb, framebuffer->width, framebuffer->height, framebuffer->pitch, framebuffer->bpp);
-		return 0;
-	}
-	return -ENOMEM;
-}
-
-// These are marked "static" because we don't wanna expose them all around
-// AKA they should just be seen here (kind of like private functions in cpp)
-static void putpixel(int x, int y, int color)
-{
-	// Depth isn't part of limine_framebuffer attributes so it will be 4
-	unsigned pos = x*4 + y*framebuffer->pitch;
-	fb[pos] = color & 255; // blue channel
-	fb[pos+1] = (color >> 8) & 255; // green
-	fb[pos+2] = (color >> 16) & 255; // blue
-}
-
-static void draw_char(char c, int px, int py, int fg, int bg)
-{
-	uint8_t* glyph = glyphs + ((unsigned char)c * FONT_HEIGHT);
-
-	for (size_t y=0; y<FONT_HEIGHT; y++)
-	{
-		uint8_t row = glyph[y];
-		for (size_t x=0; x<8; x++)
-		{
-			int color = (row & (0x80 >> x)) ? fg : bg;
-			putpixel(px+x, py+y, color);
-		}
-	}
-}
-
-static void erase_char(int px, int py)
-{
-	for (size_t y=0; y<FONT_HEIGHT; y++)
-	{
-		for (size_t x=0; x<8; x++)
-		{
-			// Black
-			putpixel(px+x, py+y, 0);
-		}
-	}
 }
 
 static inline size_t term_max_lines(void)
@@ -95,6 +47,69 @@ static inline size_t term_max_lines(void)
 	return framebuffer->height / FONT_HEIGHT;
 }
 
+int term_init()
+{
+	// Get framebuffer address from Limine struct
+	
+	if (!boot_ctx.fb)
+	{
+		return -ENOMEM;
+	}
+
+	framebuffer = boot_ctx.fb;
+	fb = (uint8_t*)framebuffer->address;
+
+	memset(lines_length, 0, sizeof(lines_length));
+
+	DEBUG("terminal initialized, fb=0x%p (width=%u height=%u pitch=%u bpp=%u)", fb, framebuffer->width, framebuffer->height, framebuffer->pitch, framebuffer->bpp);
+	return 0;
+}
+
+// These are marked "static" because we don't wanna expose them all around
+// AKA they should just be seen here (kind of like private functions in cpp)
+static inline void putpixel(size_t x, size_t y, uint32_t color)
+{
+	// Guard so we don't write past fb boundaries
+	if (x >= framebuffer->width || y >= framebuffer->height) return;
+	// Depth isn't part of limine_framebuffer attributes so it will be 4
+	size_t pos = x*4 + y*framebuffer->pitch;
+	fb[pos] = color & 255; // blue channel
+	fb[pos+1] = (color >> 8) & 255; // green
+	fb[pos+2] = (color >> 16) & 255; // blue
+}
+
+static void draw_char(char c, size_t px, size_t py, uint32_t fg, uint32_t bg)
+{
+	// So we cannot write past fb
+	if (px+FONT_WIDTH > framebuffer->width || py+FONT_HEIGHT > framebuffer->height) return;
+
+	uint8_t* glyph = glyphs + ((unsigned char)c * FONT_HEIGHT);
+
+	for (size_t y=0; y<FONT_HEIGHT; y++)
+	{
+		uint8_t row = glyph[y];
+		for (size_t x=0; x<FONT_WIDTH; x++)
+		{
+			uint32_t color = (row & (0x80 >> x)) ? fg : bg;
+			putpixel(px+x, py+y, color);
+		}
+	}
+}
+
+static void erase_char(size_t px, size_t py)
+{
+	if (px+FONT_WIDTH > framebuffer->width || py+FONT_HEIGHT > framebuffer->height) return;
+
+	for (size_t y=0; y<FONT_HEIGHT; y++)
+	{
+		for (size_t x=0; x<FONT_HEIGHT; x++)
+		{
+			// Black
+			putpixel(px+x, py+y, 0);
+		}
+	}
+}
+
 void term_scroll()
 {
 	const size_t row_height = FONT_HEIGHT;
@@ -121,71 +136,63 @@ void term_scroll()
 	}
 
 	lines_length[max_lines - 1] = 0;
-
-	if (cursor.y > 0)
-	{
-		cursor.y--;
-	}
 }
 
 
 void putchar(char c)
 {
-	if ((c == '\n') && ((cursor.y+1)*FONT_HEIGHT >= framebuffer->height))
+	const size_t max_cols = term_max_cols();
-	{
+	const size_t max_lines = term_max_lines();
-		term_scroll();
-		return;
-	} 
 
-	if (c == '\n')
+	if (c == '\n') {
-	{
 		lines_length[cursor.y] = cursor.x;
 		cursor.x = 0;
-		cursor.y++;
+
+		if (cursor.y + 1 >= max_lines)
+		{
+			term_scroll();
+		}
+		else
+		{
+			cursor.y++;
+		}
 		return;
 	}
 
-	// TODO: Improperly handled.
+	if (c == '\b') 
-	// When we're on an empty line it should get to the upper line's last character
-	// NOT just the last position possible; we would need to track the last line's character amount for that
-	if (c == '\b')
 	{
-		if (cursor.x == 0 && cursor.y == 0)
+		if (cursor.x > 0) 
+		{
+			cursor.x--;
+		}
+		else if (cursor.y > 0)
+		{
+			cursor.y--;
+			cursor.x = lines_length[cursor.y];
+		}
+		else
 		{
-			// Top-left corner
 			return;
 		}
 
-		if (cursor.x == 0)
+		erase_char(cursor.x * FONT_WIDTH, cursor.y * FONT_HEIGHT);
-		{
-			cursor.y--;
-			// cursor.x = (framebuffer->width / FONT_WIDTH) -1; // here
-			cursor.x = lines_length[cursor.y];
-		}
-		else {
-			cursor.x--;
-		}
-
-		int px = cursor.x * FONT_WIDTH;
-		int py = cursor.y * FONT_HEIGHT;
-		erase_char(px, py);
 		return;
 	}
 
-	if ((cursor.x+1)*FONT_WIDTH >= framebuffer->width)
+	if (cursor.x >= max_cols) 
 	{
 		cursor.x = 0;
-		cursor.y++;
+		if (cursor.y + 1 >= max_lines)
+		{
+			term_scroll();
+		}
+		else
+		{
+			cursor.y++;
+		}
 	}
 
-	if ((cursor.y+1)*FONT_HEIGHT >= framebuffer->height)
+	draw_char(c, cursor.x * FONT_WIDTH, cursor.y * FONT_HEIGHT, WHITE, BLACK);
-	{
-		term_scroll();
-	}
-
-	int px = cursor.x * FONT_WIDTH;
-	int py = cursor.y * FONT_HEIGHT;
-	draw_char(c, px, py, WHITE, BLACK);
 	cursor.x++;
 }
 
@@ -198,7 +205,7 @@ void _putchar(char character)
 // Debug-printing
 void kputs(const char* str)
 {
-	unsigned int i=0;
+	size_t i=0;
 	while (str[i] != 0)
 	{
 		putchar(str[i]);