big chungus

* fix a heap corruption bug
* add qemu support
* add an ATA driver
* add an USTAR read-only file system
* boot from disk instead of floppy
* font rendering
* image rendering
* PCI enumeration
* init script

20 files changed, 666 insertions, 168 deletions

diff --git a/stage3/anna.c b/stage3/anna.c
deleted file mode 100644
index d590ee7..0000000
--- a/stage3/anna.c
+++ /dev/null
@@ -1,21 +0,0 @@
-#include "font.h"
-
-void uwu()
-{
-	print(
-		"      --------    -------- "  "\n"
-		"  --/         \\  /         \\--" "\n"
-		" /             \\/             \\"  "\n"
-		"/                              \\" "\n"
-		"|                              |" "\n"
-		"|             anna             |" "\n"
-		"\\                              /" "\n"
-		" \\                            /" "\n"
-		"   \\                        /" "\n"
-		"     \\                    /" "\n"
-		"       \\                /" "\n"
-		"         \\            /" "\n"
-		"           \\        /" "\n"
-		"             \\    /" "\n"
-		"               \\/" "\n");
-}
diff --git a/stage3/anna.h b/stage3/anna.h
deleted file mode 100644
index 42bb664..0000000
--- a/stage3/anna.h
+++ /dev/null
@@ -1,6 +0,0 @@
-#ifndef ANNA_H
-#define ANNA_H
-
-void uwu();
-
-#endif
diff --git a/stage3/ata.c b/stage3/ata.c
new file mode 100644
index 0000000..ccfd695
--- /dev/null
+++ b/stage3/ata.c
@@ -0,0 +1,158 @@
+#include "ata.h"
+#include "halt.h"
+#include "heap.h"
+#include "io.h"
+#include "font.h"
+
+#define ATA_IO_DATA 0
+#define ATA_IO_ERR 1
+#define ATA_IO_FEATURES 1
+#define ATA_IO_SECTORS 2
+#define ATA_IO_LBA_LOW 3
+#define ATA_IO_LBA_MID 4
+#define ATA_IO_LBA_HIGH 5
+#define ATA_IO_HEAD 6
+#define ATA_IO_STATUS 7
+#define ATA_IO_COMMAND 7
+
+#define IO_ATA0_DATA 0x1F0
+#define IO_ATA0_CTRL 0x3F6
+
+#define ATA_CMD_IDENTIFY 0xEC
+#define ATA_CMD_READ_SECTORS_EXT 0x24
+
+typedef struct __attribute__((packed)) {
+	bool err : 1;
+	bool idx : 1;
+	bool corr : 1; // corrected data
+	bool drq : 1;  // has data or ready to accept data
+	bool srv : 1;  // overlapped
+	bool df : 1;   // drive fault
+	bool rdy : 1;  // clear if spun down or error
+	bool bsy : 1;  // preparing/busy
+} ata_status;
+
+typedef struct {
+	unsigned int bits : 4;
+	bool doll : 1; 
+	bool one0 : 1;
+	bool lba : 1;
+	bool one1 : 1;
+} __attribute__((packed)) ata_head;
+
+void ata_recv(u16 *buffer)
+{
+	for (;;) {
+		ata_status status = BITCAST(inb(IO_ATA0_DATA + ATA_IO_STATUS), u8, ata_status);
+
+		if (status.err) {
+			u8 err = inb(IO_ATA0_DATA + ATA_IO_ERR);
+
+			const char *errors[] = {
+				"address mark not found\n",
+				"track zero not found\n",
+				"aborted command\n",
+				"media change request\n",
+				"id not found\n",
+				"media changed\n",
+				"uncorrectable data error\n",
+				"bad block detected\n",
+			};
+
+			for (int i = 0; i < 8; i++)
+				if (err & (1 << i))
+					print(errors[i]);
+			
+			panic("ata0-witch error\n");
+		} else if (status.drq)
+			break;
+	}
+
+	for (int i = 0; i < 256; i++)
+		buffer[i] = inw(IO_ATA0_DATA + ATA_IO_DATA);
+}
+
+void ata_delay()
+{
+	for (int i = 0; i < 15; i++)
+		inb(IO_ATA0_DATA + ATA_IO_STATUS);	
+}
+
+void ata_init()
+{
+	u8 floating = inb(IO_ATA0_DATA + ATA_IO_STATUS);
+	if (floating == 0xFF)
+		panic("ata0 floating\n");
+
+	outb(IO_ATA0_DATA + ATA_IO_HEAD, BITCAST(((ata_head) {
+		.bits = 0,
+		.doll = false,
+		.one0 = true,
+		.lba = false,
+		.one1 = true,
+	}), ata_head, u8));
+	ata_delay();
+	outb(IO_ATA0_DATA + ATA_IO_LBA_LOW, 0);
+	outb(IO_ATA0_DATA + ATA_IO_LBA_MID, 0);
+	outb(IO_ATA0_DATA + ATA_IO_LBA_HIGH, 0);
+	outb(IO_ATA0_DATA + ATA_IO_COMMAND, ATA_CMD_IDENTIFY);
+
+	u8 status_byte = inb(IO_ATA0_DATA + ATA_IO_STATUS);
+	if (status_byte == 0)
+		panic("no ata0-witch drive\n");
+
+	while (BITCAST(status_byte, u8, ata_status).bsy)
+		status_byte = inb(IO_ATA0_DATA + ATA_IO_STATUS);
+
+	if (inb(IO_ATA0_DATA + ATA_IO_LBA_MID) != 0 || inb(IO_ATA0_DATA + ATA_IO_LBA_HIGH) != 0)
+		panic("ata0-witch is not ATA\n");
+
+	u16 *idvec = malloc(256 * sizeof *idvec);
+	ata_recv(idvec);
+
+	if (!(idvec[83] & (1 << 10)))
+		panic("ata0-witch does not support LBA48 mode\n");
+
+	// u64 lba48_sectors = *(u64 *) &idvec[100];
+	// print_num(lba48_sectors, 10, 0); print("\n");
+
+	free(idvec);
+}
+
+void ata_read(u64 lba, u16 sectors, void *buffer)
+{
+	outb(IO_ATA0_DATA + ATA_IO_HEAD, BITCAST(((ata_head) {
+		.bits = 0,
+		.doll = false,
+		.one0 = true,
+		.lba = true,
+		.one1 = true,
+	}), ata_head, u8));
+	ata_delay();
+	outb(IO_ATA0_DATA + ATA_IO_SECTORS, sectors >> 8);
+	outb(IO_ATA0_DATA + ATA_IO_LBA_LOW, (lba >> 24) & 0xff);
+	outb(IO_ATA0_DATA + ATA_IO_LBA_MID, (lba >> 32) & 0xff);
+	outb(IO_ATA0_DATA + ATA_IO_LBA_HIGH, (lba >> 40) & 0xff);
+	outb(IO_ATA0_DATA + ATA_IO_SECTORS, sectors & 0xff);
+	outb(IO_ATA0_DATA + ATA_IO_LBA_LOW, lba & 0xff);
+	outb(IO_ATA0_DATA + ATA_IO_LBA_MID, (lba >> 8) & 0xff);
+	outb(IO_ATA0_DATA + ATA_IO_LBA_HIGH, (lba >> 16) & 0xff);
+	outb(IO_ATA0_DATA + ATA_IO_COMMAND, ATA_CMD_READ_SECTORS_EXT);
+
+	for (u16 i = 0; i < sectors; i++)
+		ata_recv(buffer + i*512);
+}
+
+void *ata_read_full(u64 lba, u64 sectors)
+{
+	void *buffer = malloc(512 * sectors);
+
+	for (u64 off = 0; off < sectors; off += 0x10000) {
+		u64 sects = sectors - off;
+		if (sects >= 0x10000)
+			sects = 0;
+		ata_read(lba + off, (u16) sects, buffer + off * 512);
+	}
+
+	return buffer;
+}
diff --git a/stage3/ata.h b/stage3/ata.h
new file mode 100644
index 0000000..56743e8
--- /dev/null
+++ b/stage3/ata.h
@@ -0,0 +1,12 @@
+#ifndef ATA_H
+#define ATA_H
+
+#include "def.h"
+
+void ata_recv(u16 *buffer);
+void ata_delay();
+void ata_init();
+void ata_read(u64 lba, u16 sectors, void *buffer);
+void *ata_read_full(u64 lba, u64 sectors);
+
+#endif
diff --git a/stage3/font.c b/stage3/font.c
index 291cdb1..9e315e6 100644
--- a/stage3/font.c
+++ b/stage3/font.c
@@ -1,10 +1,17 @@
 #include "font.h"
-#include "letters.h"
+#include "font_classic.h"
 #include "gfx.h"
+#include "heap.h"
+#include "memory.h"
 
 // important: must be a multiple of 2, else code won't work
 #define TAB_SIZE 4
 
+#define CHAR_WIDTH  8
+#define CHAR_HEIGHT 16
+
+static u8 *font; // u8[256][16]
+
 static u16 font_size;
 
 static u16 outer_width, outer_height;
@@ -12,17 +19,55 @@ static u16 cursor_x, cursor_y;
 
 static u16 screen_width, screen_height;
 
-void set_font_size(u16 size)
+void font_init()
+{
+	font = malloc(256 * 16);
+}
+
+void font_set_size(u16 size)
 {
 	font_size = size;
 
-	outer_width  = (LETTER_WIDTH  + 2) * font_size;
-	outer_height = (LETTER_HEIGHT + 2) * font_size;
+	outer_width  = CHAR_WIDTH  * font_size;
+	outer_height = CHAR_HEIGHT * font_size;
 
 	screen_width  = gfx_info->width  / outer_width;
 	screen_height = gfx_info->height / outer_height;
 }
 
+void font_load_blob(const void *blob)
+{
+	memcpy(font, blob, 256*16);
+}
+
+void font_load_classic()
+{
+	memset(font, 0, 256 * 16);
+
+	classic_char *cfont = font_classic();
+
+	int scale = 2;
+	int xpad = (CHAR_WIDTH  - CLASSIC_CHAR_WIDTH  * scale) / 2;
+	int ypad = (CHAR_HEIGHT - CLASSIC_CHAR_HEIGHT * scale) / 2;
+
+	for (int i = 0; i < 255; i++)
+	for (int xc = 0; xc < CLASSIC_CHAR_WIDTH;  xc++)
+	for (int yc = 0; yc < CLASSIC_CHAR_HEIGHT; yc++) {
+		if (!cfont[i].data[yc * CLASSIC_CHAR_WIDTH + xc])
+			continue;
+
+		for (int xf = 0; xf < scale; xf++)
+		for (int yf = 0; yf < scale; yf++) {
+			int x = xc * scale + xpad + xf;
+			int y = yc * scale + ypad + yf;
+
+			font[i * CHAR_HEIGHT + y] |= (1 << x);
+		}
+	}
+
+	free(cfont);
+}
+
 static void render_char(u8 c)
 {
 	u16 base_x = cursor_x * outer_width;
@@ -30,14 +75,14 @@ static void render_char(u8 c)
 
 	gfx_set_area(base_x, base_y, outer_width, outer_height, 0xFF000000);
 
-	for (u16 x = 0; x < LETTER_WIDTH;  x++)
-	for (u16 y = 0; y < LETTER_HEIGHT; y++) {
-		if (!letters[c].data[y * LETTER_WIDTH + x])
+	for (u16 x = 0; x < CHAR_WIDTH;  x++)
+	for (u16 y = 0; y < CHAR_HEIGHT; y++) {
+		if (!(font[c * CHAR_HEIGHT + y] & (1 << x)))
 			continue;
 
 		gfx_set_area(
-			base_x + (x + 1) * font_size,
-			base_y + (y + 1) * font_size,
+			base_x + x * font_size,
+			base_y + y * font_size,
 			font_size, font_size, 0xFFFFFFFF);
 	}
 }
@@ -103,8 +148,13 @@ void print(const char *line)
 		print_char(*line++);
 }
 
+void printn(const char *line, usize len)
+{
+	for (usize i = 0; i < len; i++)
+		print_char(*line++);
+}
 
-void print_num(u64 x, u8 base, u8 pad)
+void print_padded(u64 x, u8 base, u8 pad_len, char pad_char)
 {
 	char digit[65];
 	char *ptr = &digit[64];
@@ -116,8 +166,13 @@ void print_num(u64 x, u8 base, u8 pad)
 		x /= base;
 	} while (x != 0);
 
-	while (ptr > digit + 64 - pad)
-		*--ptr = ' ';
+	while (ptr > digit + 64 - pad_len)
+		*--ptr = pad_char;
 
 	print(ptr);
 }
+
+void print_num(u64 x, u8 base, u8 pad)
+{
+	print_padded(x, base, pad, ' ');
+}
diff --git a/stage3/font.h b/stage3/font.h
index 009d1de..ec99118 100644
--- a/stage3/font.h
+++ b/stage3/font.h
@@ -3,9 +3,15 @@
 
 #include "def.h"
 
+void font_init();
+void font_set_size(u16 size);
+void font_load_blob(const void *blob);
+void font_load_classic();
+
 void print(const char *line);
-void set_font_size(u16 size);
+void printn(const char *line, usize len);
 void print_char(char c);
-void print_num(u64 x, u8 base, u8 pad);
+void print_num(u64 x, u8 base, u8 pad_len);
+void print_padded(u64 x, u8 base, u8 pad_len, char pad_char);
 
 #endif
diff --git a/stage3/letters.c b/stage3/font_classic.c
index 43f78fb..4346f16 100644
--- a/stage3/letters.c
+++ b/stage3/font_classic.c
@@ -1,490 +1,495 @@
-#include "letters.h"
+#include "font_classic.h"
+#include "heap.h"
+#include "memory.h"
 
-Letter letters[256];
-
-void letters_init()
+classic_char *font_classic()
 {
-	letters[' '] = (Letter) {{
+	classic_char *font = malloc(256 * sizeof *font);
+	memset(font, 0, 256 * sizeof *font);
+
+	font[' '] = (classic_char) {{
 		0, 0, 0,
 		0, 0, 0,
 		0, 0, 0,
 		0, 0, 0,
 		0, 0, 0
 	}};
-	letters['!'] = (Letter) {{
+	font['!'] = (classic_char) {{
 		0, 1, 0,
 		0, 1, 0,
 		0, 1, 0,
 		0, 0, 0,
 		0, 1, 0
 	}};
-	letters['\"'] = (Letter) {{
+	font['\"'] = (classic_char) {{
 		1, 0, 1,
 		1, 0, 1,
 		0, 0, 0,
 		0, 0, 0,
 		0, 0, 0
 	}};
-	letters['#'] = (Letter) {{
+	font['#'] = (classic_char) {{
 		1, 0, 1,
 		1, 1, 1,
 		1, 0, 1,
 		1, 1, 1,
 		1, 0, 1
 	}};
-	letters['$'] = (Letter) {{
+	font['$'] = (classic_char) {{
 		0, 1, 0,
 		1, 1, 1,
 		0, 1, 0,
 		1, 1, 1,
 		0, 1, 0
 	}};
-	letters['%'] = (Letter) {{
+	font['%'] = (classic_char) {{
 		1, 0, 1,
 		0, 0, 1,
 		0, 1, 0,
 		1, 0, 0,
 		1, 0, 1
 	}};
-	letters['&'] = (Letter) {{
+	font['&'] = (classic_char) {{
 		1, 1, 0,
 		1, 0, 0,
 		1, 1, 1,
 		1, 0, 1,
 		1, 1, 1
 	}};
-	letters['\''] = (Letter) {{
+	font['\''] = (classic_char) {{
 		0, 1, 0,
 		0, 1, 0,
 		0, 0, 0,
 		0, 0, 0,
 		0, 0, 0
 	}};
-	letters['('] = (Letter) {{
+	font['('] = (classic_char) {{
 		0, 1, 0,
 		1, 0, 0,
 		1, 0, 0,
 		1, 0, 0,
 		0, 1, 0
 	}};
-	letters[')'] = (Letter) {{
+	font[')'] = (classic_char) {{
 		0, 1, 0,
 		0, 0, 1,
 		0, 0, 1,
 		0, 0, 1,
 		0, 1, 0
 	}};
-	letters['*'] = (Letter) {{
+	font['*'] = (classic_char) {{
 		1, 0, 1,
 		0, 1, 0,
 		1, 0, 1,
 		0, 0, 0,
 		0, 0, 0
 	}};
-	letters['+'] = (Letter) {{
+	font['+'] = (classic_char) {{
 		0, 0, 0,
 		0, 1, 0,
 		1, 1, 1,
 		0, 1, 0,
 		0, 0, 0
 	}};
-	letters[','] = (Letter) {{
+	font[','] = (classic_char) {{
 		0, 0, 0,
 		0, 0, 0,
 		0, 1, 0,
 		0, 1, 0,
 		1, 0, 0
 	}};
-	letters['-'] = (Letter) {{
+	font['-'] = (classic_char) {{
 		0, 0, 0,
 		0, 0, 0,
 		1, 1, 1,
 		0, 0, 0,
 		0, 0, 0
 	}};
-	letters['.'] = (Letter) {{
+	font['.'] = (classic_char) {{
 		0, 0, 0,
 		0, 0, 0,
 		0, 0, 0,
 		0, 0, 0,
 		0, 1, 0
 	}};
-	letters['/'] = (Letter) {{
+	font['/'] = (classic_char) {{
 		0, 0, 1,
 		0, 0, 1,
 		0, 1, 0,
 		1, 0, 0,
 		1, 0, 0
 	}};
-	letters['0'] = (Letter) {{
+	font['0'] = (classic_char) {{
 		0, 1, 0,
 		1, 0, 1,
 		1, 0, 1,
 		1, 0, 1,
 		0, 1, 0
 	}};
-	letters['1'] = (Letter) {{
+	font['1'] = (classic_char) {{
 		0, 0, 1,
 		0, 1, 1,
 		0, 0, 1,
 		0, 0, 1,
 		0, 0, 1
 	}};
-	letters['2'] = (Letter) {{
+	font['2'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 1,
 		0, 1, 0,
 		1, 0, 0,
 		1, 1, 1
 	}};
-	letters['3'] = (Letter) {{
+	font['3'] = (classic_char) {{
 		1, 1, 1,
 		0, 0, 1,
 		0, 1, 1,
 		0, 0, 1,
 		1, 1, 1
 	}};
-	letters['4'] = (Letter) {{
+	font['4'] = (classic_char) {{
 		1, 0, 1,
 		1, 0, 1,
 		1, 1, 1,
 		0, 0, 1,
 		0, 0, 1
 	}};
-	letters['5'] = (Letter) {{
+	font['5'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 0,
 		1, 1, 1,
 		0, 0, 1,
 		1, 1, 0
 	}};
-	letters['6'] = (Letter) {{
+	font['6'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 0,
 		1, 1, 1,
 		1, 0, 1,
 		1, 1, 1
 	}};
-	letters['7'] = (Letter) {{
+	font['7'] = (classic_char) {{
 		1, 1, 1,
 		0, 0, 1,
 		0, 1, 0,
 		1, 0, 0,
 		1, 0, 0
 	}};
-	letters['8'] = (Letter) {{
+	font['8'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 1,
 		1, 1, 1,
 		1, 0, 1,
 		1, 1, 1
 	}};
-	letters['9'] = (Letter) {{
+	font['9'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 1,
 		1, 1, 1,
 		0, 0, 1,
 		1, 1, 1
 	}};
-	letters[':'] = (Letter) {{
+	font[':'] = (classic_char) {{
 		0, 0, 0,
 		0, 1, 0,
 		0, 0, 0,
 		0, 1, 0,
 		0, 0, 0
 	}};
-	letters[';'] = (Letter) {{
+	font[';'] = (classic_char) {{
 		0, 1, 0,
 		0, 0, 0,
 		0, 1, 0,
 		0, 1, 0,
 		1, 0, 0
 	}};
-	letters['<'] = (Letter) {{
+	font['<'] = (classic_char) {{
 		0, 0, 0,
 		0, 1, 0,
 		1, 0, 0,
 		0, 1, 0,
 		0, 0, 0
 	}};
-	letters['='] = (Letter) {{
+	font['='] = (classic_char) {{
 		0, 0, 0,
 		1, 1, 1,
 		0, 0, 0,
 		1, 1, 1,
 		0, 0, 0
 	}};
-	letters['>'] = (Letter) {{
+	font['>'] = (classic_char) {{
 		0, 0, 0,
 		0, 1, 0,
 		0, 0, 1,
 		0, 1, 0,
 		0, 0, 0
 	}};
-	letters['?'] = (Letter) {{
+	font['?'] = (classic_char) {{
 		1, 1, 1,
 		0, 0, 1,
 		0, 1, 0,
 		0, 0, 0,
 		0, 1, 0
 	}};
-	letters['@'] = (Letter) {{
+	font['@'] = (classic_char) {{
 		0, 0, 0,
 		1, 1, 1,
 		1, 0, 1,
 		1, 1, 1,
 		1, 1, 1
 	}};
-	letters['['] = (Letter) {{
+	font['['] = (classic_char) {{
 		1, 1, 0,
 		1, 0, 0,
 		1, 0, 0,
 		1, 0, 0,
 		1, 1, 0
 	}};
-	letters[']'] = (Letter) {{
+	font[']'] = (classic_char) {{
 		0, 1, 1,
 		0, 0, 1,
 		0, 0, 1,
 		0, 0, 1,
 		0, 1, 1
 	}};
-	letters['\\'] = (Letter) {{
+	font['\\'] = (classic_char) {{
 		1, 0, 0,
 		1, 0, 0,
 		0, 1, 0,
 		0, 0, 1,
 		0, 0, 1
 	}};
-	letters['^'] = (Letter) {{
+	font['^'] = (classic_char) {{
 		0, 1, 0,
 		1, 0, 1,
 		0, 0, 0,
 		0, 0, 0,
 		0, 0, 0
 	}};
-	letters['_'] = (Letter) {{
+	font['_'] = (classic_char) {{
 		0, 0, 0,
 		0, 0, 0,
 		0, 0, 0,
 		0, 0, 0,
 		1, 1, 1
 	}};
-	letters['`'] = (Letter) {{
+	font['`'] = (classic_char) {{
 		0, 1, 0,
 		0, 0, 1,
 		0, 0, 0,
 		0, 0, 0,
 		0, 0, 0
 	}};
-	letters['~'] = (Letter) {{
+	font['~'] = (classic_char) {{
 		0, 0, 0,
 		0, 0, 1,
 		1, 1, 1,
 		1, 0, 0,
 		0, 0, 0
 	}};
-	letters['{'] = (Letter) {{
+	font['{'] = (classic_char) {{
 		0, 1, 1,
 		0, 1, 0,
 		1, 1, 0,
 		0, 1, 0,
 		0, 1, 1
 	}};
-	letters['}'] = (Letter) {{
+	font['}'] = (classic_char) {{
 		1, 1, 0,
 		0, 1, 0,
 		0, 1, 1,
 		0, 1, 0,
 		1, 1, 0
 	}};
-	letters['|'] = (Letter) {{
+	font['|'] = (classic_char) {{
 		0, 1, 0,
 		0, 1, 0,
 		0, 1, 0,
 		0, 1, 0,
 		0, 1, 0
 	}};
-	letters['A'] = letters['a'] = (Letter) {{
+	font['A'] = font['a'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 1,
 		1, 1, 1,
 		1, 0, 1,
 		1, 0, 1
 	}};
-	letters['B'] = letters['b'] = (Letter) {{
+	font['B'] = font['b'] = (classic_char) {{
 		1, 1, 0,
 		1, 0, 1,
 		1, 1, 1,
 		1, 0, 1,
 		1, 1, 0
 	}};
-	letters['C'] = letters['c'] = (Letter) {{
+	font['C'] = font['c'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 0,
 		1, 0, 0,
 		1, 0, 0,
 		1, 1, 1
 	}};
-	letters['D'] = letters['d'] = (Letter) {{
+	font['D'] = font['d'] = (classic_char) {{
 		1, 1, 0,
 		1, 0, 1,
 		1, 0, 1,
 		1, 0, 1,
 		1, 1, 0
 	}};
-	letters['E'] = letters['e'] = (Letter) {{
+	font['E'] = font['e'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 0,
 		1, 1, 1,
 		1, 0, 0,
 		1, 1, 1
 	}};
-	letters['F'] = letters['f'] = (Letter) {{
+	font['F'] = font['f'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 0,
 		1, 1, 1,
 		1, 0, 0,
 		1, 0, 0
 	}};
-	letters['G'] = letters['g'] = (Letter) {{
+	font['G'] = font['g'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 0,
 		1, 0, 1,
 		1, 0, 1,
 		1, 1, 1
 	}};
-	letters['H'] = letters['h'] = (Letter) {{
+	font['H'] = font['h'] = (classic_char) {{
 		1, 0, 1,
 		1, 0, 1,
 		1, 1, 1,
 		1, 0, 1,
 		1, 0, 1
 	}};
-	letters['I'] = letters['i'] = (Letter) {{
+	font['I'] = font['i'] = (classic_char) {{
 		1, 1, 1,
 		0, 1, 0,
 		0, 1, 0,
 		0, 1, 0,
 		1, 1, 1
 	}};
-	letters['J'] = letters['j'] = (Letter) {{
+	font['J'] = font['j'] = (classic_char) {{
 		0, 0, 1,
 		0, 0, 1,
 		0, 0, 1,
 		0, 0, 1,
 		1, 1, 1
 	}};
-	letters['K'] = letters['k'] = (Letter) {{
+	font['K'] = font['k'] = (classic_char) {{
 		1, 0, 1,
 		1, 1, 0,
 		1, 0, 0,
 		1, 1, 0,
 		1, 0, 1,
 	}};
-	letters['L'] = letters['l'] = (Letter) {{
+	font['L'] = font['l'] = (classic_char) {{
 		1, 0, 0,
 		1, 0, 0,
 		1, 0, 0,
 		1, 0, 0,
 		1, 1, 1
 	}};
-	letters['M'] = letters['m'] = (Letter) {{
+	font['M'] = font['m'] = (classic_char) {{
 		1, 0, 1,
 		1, 1, 1,
 		1, 0, 1,
 		1, 0, 1,
 		1, 0, 1
 	}};
-	letters['N'] = letters['n'] = (Letter) {{
+	font['N'] = font['n'] = (classic_char) {{
 		1, 0, 1,
 		1, 0, 1,
 		1, 1, 1,
 		1, 1, 1,
 		1, 0, 1
 	}};
-	letters['O'] = letters['o'] = (Letter) {{
+	font['O'] = font['o'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 1,
 		1, 0, 1,
 		1, 0, 1,
 		1, 1, 1
 	}};
-	letters['P'] = letters['p'] = (Letter) {{
+	font['P'] = font['p'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 1,
 		1, 1, 1,
 		1, 0, 0,
 		1, 0, 0
 	}};
-	letters['Q'] = letters['q'] = (Letter) {{
+	font['Q'] = font['q'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 1,
 		1, 0, 1,
 		1, 1, 1,
 		0, 0, 1
 	}};
-	letters['R'] = letters['r'] = (Letter) {{
+	font['R'] = font['r'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 1,
 		1, 1, 1,
 		1, 1, 0,
 		1, 0, 1
 	}};
-	letters['S'] = letters['s'] = (Letter) {{
+	font['S'] = font['s'] = (classic_char) {{
 		1, 1, 1,
 		1, 0, 0,
 		1, 1, 1,
 		0, 0, 1,
 		1, 1, 1
 	}};
-	letters['T'] = letters['t'] = (Letter) {{
+	font['T'] = font['t'] = (classic_char) {{
 		1, 1, 1,
 		0, 1, 0,
 		0, 1, 0,
 		0, 1, 0,
 		0, 1, 0
 	}};
-	letters['U'] = letters['u'] = (Letter) {{
+	font['U'] = font['u'] = (classic_char) {{
 		1, 0, 1,
 		1, 0, 1,
 		1, 0, 1,
 		1, 0, 1,
 		1, 1, 1
 	}};
-	letters['V'] = letters['v'] = (Letter) {{
+	font['V'] = font['v'] = (classic_char) {{
 		1, 0, 1,
 		1, 0, 1,
 		1, 0, 1,
 		1, 0, 1,
 		0, 1, 0
 	}};
-	letters['W'] = letters['w'] = (Letter) {{
+	font['W'] = font['w'] = (classic_char) {{
 		1, 0, 1,
 		1, 0, 1,
 		1, 0, 1,
 		1, 1, 1,
 		1, 0, 1
 	}};
-	letters['X'] = letters['x'] = (Letter) {{
+	font['X'] = font['x'] = (classic_char) {{
 		1, 0, 1,
 		1, 0, 1,
 		0, 1, 0,
 		1, 0, 1,
 		1, 0, 1
 	}};
-	letters['Y'] = letters['y'] = (Letter) {{
+	font['Y'] = font['y'] = (classic_char) {{
 		1, 0, 1,
 		1, 0, 1,
 		1, 1, 1,
 		0, 1, 0,
 		0, 1, 0
 	}};
-	letters['Z'] = letters['z'] = (Letter) {{
+	font['Z'] = font['z'] = (classic_char) {{
 		1, 1, 1,
 		0, 0, 1,
 		0, 1, 0,
 		1, 0, 0,
 		1, 1, 1
 	}};
+
+	return font;
 }
diff --git a/stage3/font_classic.h b/stage3/font_classic.h
new file mode 100644
index 0000000..cc80873
--- /dev/null
+++ b/stage3/font_classic.h
@@ -0,0 +1,15 @@
+#ifndef FONT_CLASSIC_H
+#define FONT_CLASSIC_H
+
+#include "def.h"
+
+#define CLASSIC_CHAR_WIDTH  3
+#define CLASSIC_CHAR_HEIGHT 5
+
+typedef struct __attribute__((packed)) {
+	u8 data[CLASSIC_CHAR_WIDTH * CLASSIC_CHAR_HEIGHT];
+} classic_char;
+
+classic_char *font_classic();
+
+#endif
diff --git a/stage3/fs.c b/stage3/fs.c
new file mode 100644
index 0000000..9f7ea51
--- /dev/null
+++ b/stage3/fs.c
@@ -0,0 +1,31 @@
+#include "fs.h"
+#include "ata.h"
+#include "string.h"
+#include "memory.h"
+#include "heap.h"
+
+file fs_read(const char *filename)
+{
+	u64 start = (*(u32 *) (0x1000-10-8))/512;
+
+	for (;;) {
+		u8 *info = ata_read_full(start, 1);
+
+		if (memcmp(info+257, "ustar", 5) != 0) {
+			free(info);
+			return (file) { .len = 0, .data = nil };
+		}
+
+		u8 *infop = info+124;
+		usize fsize = parse_num(&infop, 8, 11);
+		usize fsect = (fsize+511)/512;
+
+		if (memcmp(info, filename, strlen(filename) + 1) == 0) {
+			free(info);
+			return (file) { .len = fsize, .data = ata_read_full(start+1, fsect) };
+		} else {
+			free(info);
+			start += 1 + fsect;
+		}
+	}
+}
diff --git a/stage3/fs.h b/stage3/fs.h
new file mode 100644
index 0000000..b585577
--- /dev/null
+++ b/stage3/fs.h
@@ -0,0 +1,13 @@
+#ifndef FS_H
+#define FS_H
+
+#include "def.h"
+
+typedef struct {
+	usize len;
+	void *data;
+} file;
+
+file fs_read(const char *filename);
+
+#endif
diff --git a/stage3/gfx.c b/stage3/gfx.c
index 2afc766..79c76a3 100644
--- a/stage3/gfx.c
+++ b/stage3/gfx.c
@@ -1,4 +1,5 @@
 #include "gfx.h"
+#include "memory.h"
 
 struct GfxInfo *gfx_info = (void *) (0x1000-10);
 
@@ -6,10 +7,10 @@ struct GfxInfo *gfx_info = (void *) (0x1000-10);
 u32 make_color(color col)
 {
 	return ((u32) 0)
-		& ((u32) col.r << 0)
-		& ((u32) col.g << 8)
-		& ((u32) col.b << 16)
-		& ((u32) col.a << 24);
+		| ((u32) col.b << 0)
+		| ((u32) col.g << 8)
+		| ((u32) col.r << 16)
+		| ((u32) col.a << 24);
 }
 
 void gfx_set_pixel(u16 x, u16 y, u32 col)
@@ -30,3 +31,10 @@ void gfx_set_area(u16 x, u16 y, u16 w, u16 h, u32 col)
 			*((u32 *) rbeg) = col;
 	}
 }
+
+void gfx_draw_img(u16 x, u16 y, u16 w, u16 h, color *img)
+{
+	void *cbeg = (void *) (u64) (gfx_info->framebuffer + y * gfx_info->pitch + x * sizeof(color));
+	for (u16 yi = 0; yi < h; cbeg += gfx_info->pitch, yi++)
+		memcpy(cbeg, img + yi * w, w * sizeof(color));
+}
diff --git a/stage3/gfx.h b/stage3/gfx.h
index 47e98db..6eee074 100644
--- a/stage3/gfx.h
+++ b/stage3/gfx.h
@@ -10,12 +10,13 @@ extern struct __attribute__((packed)) GfxInfo {
 	u32 framebuffer;
 } *gfx_info;
 
-typedef struct {
+typedef struct __attribute__((packed)) {
 	u8 r, g, b, a;
 } color;
 
 u32 make_color(color col);
 void gfx_set_pixel(u16 x, u16 y, u32 col);
 void gfx_set_area(u16 x, u16 y, u16 w, u16 h, u32 col);
+void gfx_draw_img(u16 x, u16 y, u16 w, u16 h, color *img);
 
 #endif
diff --git a/stage3/heap.c b/stage3/heap.c
index 2909ba7..dd1b23a 100644
--- a/stage3/heap.c
+++ b/stage3/heap.c
@@ -46,7 +46,7 @@ void *try_malloc(usize size)
 			prev->next = h->next;
 		} else {
 			// split
-			h->size -= size;
+			h->size -= size + sizeof(Header);
 			h = ((void *) h) + sizeof(Header) + h->size;
 			h->size = size;
 		}
diff --git a/stage3/interrupts.c b/stage3/interrupts.c
index e7b819e..71f953f 100644
--- a/stage3/interrupts.c
+++ b/stage3/interrupts.c
@@ -102,6 +102,13 @@ void interrupt_handler(interrupt_frame *frame)
 	}
 }
 
+typedef struct {
+	u16 size;
+	u64 addr;
+} __attribute__((packed)) idt_descriptor;
+
+idt_descriptor idtr;
+
 void init_interrupts()
 {
 	typedef struct {
@@ -139,12 +146,7 @@ void init_interrupts()
 		};
 	}
 
-	typedef struct {
-		u16 size;
-		u64 addr;
-	} __attribute__((packed)) idt_descriptor;
-
-	idt_descriptor idtr = {
+	idtr = (idt_descriptor) {
 		.size = 256 * sizeof *idt - 1,
 		.addr = (u64) &idt[0],
 	};
diff --git a/stage3/letters.h b/stage3/letters.h
deleted file mode 100644
index ffaa6d5..0000000
--- a/stage3/letters.h
+++ /dev/null
@@ -1,17 +0,0 @@
-#ifndef LETTERS_H
-#define LETTERS_H
-
-#include "def.h"
-
-#define LETTER_WIDTH  3
-#define LETTER_HEIGHT 5
-
-typedef struct __attribute__((packed)) {
-	u8 data[LETTER_HEIGHT * LETTER_WIDTH];
-} Letter;
-
-extern Letter letters[];
-
-void letters_init();
-
-#endif
diff --git a/stage3/main.c b/stage3/main.c
index d3ebe9d..5362984 100644
--- a/stage3/main.c
+++ b/stage3/main.c
@@ -1,20 +1,34 @@
+void kmain();
+
+void init()
+{
+	kmain();
+}
+
 #include "def.h"
 #include "paging.h"
 #include "gfx.h"
 #include "halt.h"
 #include "heap.h"
 #include "font.h"
-#include "letters.h"
 #include "interrupts.h"
 #include "pic.h"
-#include "anna.h"
-
-void init()
+#include "io.h"
+#include "memory.h"
+#include "ata.h"
+#include "fs.h"
+#include "string.h"
+#include "pci.h"
+
+void eat_whitespace(char **str)
 {
-	letters_init();
+	while (**str == ' ' || **str == '\t')
+		(*str)++;
+}
 
+void kmain()
+{
 	heap_init();
-	set_font_size(2);
 
 #define MMAP for (MemRegion *mreg = (void *) 0x500; mreg->start != nil; mreg++)
 
@@ -42,20 +56,9 @@ void init()
 	// gfx init
 	gfx_set_area(0, 0, gfx_info->width, gfx_info->height, 0xFF000000);
 
-	// charset demo
-	{
-		const u8 max =  '~' - '!' + 1;
-
-		char str[max + 1];
-		str[max] = '\0';
-
-		for (u8 i = 0; i < max; i++)
-			str[i] = i + '!';
-
-		print("charset demo:\n");
-		print(str);
-		print("\n");
-	}
+	font_init();
+	font_set_size(1);
+	font_load_classic();
 
 	// memory map
 	print("memory map:\n");
@@ -70,11 +73,130 @@ void init()
 
 	init_interrupts();
 	pic_init();
+	ata_init();
+
+	file f = fs_read("init");
+	if (f.data == nil)
+		panic("no init script");
+
+	// this is horrible horrible horrible
+	// if you read this i am genuinely sorry
+
+	char *init = malloc(f.len+1);
+	char *init_orig = init;
+	init[f.len] = '\0';
+	memcpy(init, f.data, f.len);
+	free(f.data);
+
+	for (;;) {
+		eat_whitespace(&init);
+
+		if (*init == '\0')
+			break;
+		else if (*init == '\n') {
+			init++;
+			continue;
+		}
+
+		if (strncmp(init, "echo ", strlen("echo ")) == 0) {
+			init += strlen("echo ");
+			usize idx = find_char(init, '\n');
+			printn(init, idx);
+			print("\n");
+			init += idx;
+		} else if (strncmp(init, "cat ", strlen("cat ")) == 0) {
+			init += strlen("cat ");
+			usize idx = find_char(init, '\n');
+
+			char filename[idx+1];
+			filename[idx] = '\0';
+			memcpy(filename, init, idx);
+
+			file f = fs_read(filename);
+			if (f.data == nil) {
+				print("cat: file not found: ");
+				print(filename);
+				print("\n");
+			} else {
+				printn(f.data, f.len);
+				free(f.data);
+			}
+
+			init += idx;
+		} else if (strncmp(init, "font ", strlen("font ")) == 0) {
+			init += strlen("font ");
+			usize idx = find_char(init, '\n');
+
+			char filename[idx+1];
+			filename[idx] = '\0';
+			memcpy(filename, init, idx);
+
+			file f = fs_read(filename);
+			if (f.data == nil) {
+				print("font: file not found: ");
+				print(filename);
+				print("\n");
+			} else {
+				if (f.len == 16*256)
+					font_load_blob(f.data);
+				else
+					print("font: file has wrong size\n");
+				free(f.data);
+			}
+
+			init += idx;
+		} else if (strncmp(init, "img ", strlen("img ")) == 0) {
+			init += strlen("img ");
+			usize idx = find_char(init, '\n');
+
+			char filename[idx+1];
+			filename[idx] = '\0';
+			memcpy(filename, init, idx);
+
+			file f = fs_read(filename);
+			if (f.data == nil) {
+				print("img: file not found: ");
+				print(filename);
+				print("\n");
+			} else {
+				if (f.len < 2 * sizeof(u32))
+					print("img: missing header\n");
+				else {
+					u32 width = ((u32 *) f.data)[0];
+					u32 height = ((u32 *) f.data)[1];
+					if (f.len != 2 * sizeof(u32) + width * height * sizeof(color))
+						panic("img: invalid file size\n");
+					gfx_draw_img(gfx_info->width-width, 0, width, height, f.data + 2 * sizeof(u32));
+				}
+				free(f.data);
+			}
+
+			init += idx;
+		} else if (strncmp(init, "lspci", strlen("lspci")) == 0) {
+			pci_enumerate();
+			init += find_char(init, '\n');
+		} else if (strncmp(init, "charset_demo", strlen("charset_demo")) == 0) {
+			const u8 max = '~' - '!' + 1;
+
+			char str[max + 1];
+			str[max] = '\0';
+
+			for (u8 i = 0; i < max; i++)
+				str[i] = i + '!';
+
+			print("charset demo:\n");
+			print(str);
+			print("\n");
+			init += find_char(init, '\n');
+		} else {
+			print("unknown command: ");
+			usize idx = find_char(init, '\n');
+			printn(init, idx);
+			print("\n");
+			init += idx;
+		}
+	}
 
-	uwu();
-
-	// unmask_irq(IRQ_PIT);
-	enable_irqs();
-
+	free(init_orig);
 	halt();
 }
diff --git a/stage3/pci.c b/stage3/pci.c
new file mode 100644
index 0000000..164071d
--- /dev/null
+++ b/stage3/pci.c
@@ -0,0 +1,40 @@
+#include "pci.h"
+#include "def.h"
+#include "io.h"
+#include "font.h"
+
+#define PCI_CONFIG_ADDRESS 0xCF8
+#define PCI_CONFIG_DATA 0xCFC
+
+void pci_enumerate()
+{
+	typedef struct __attribute__((packed)) {
+		u8 offset;
+		unsigned int func : 3;
+		unsigned int dev : 5;
+		u8 bus;
+		unsigned int reserved : 7;
+		bool enable : 1;
+	} pci_config_addr;
+
+	for (int bus = 0; bus < 256; bus++)
+	for (int dev = 0; dev < 32; dev++) {
+		pci_config_addr addr = {
+			.offset = 0,
+			.func = 0,
+			.dev = dev,
+			.bus = bus,
+			.enable = true,
+		};
+
+		outl(PCI_CONFIG_ADDRESS, BITCAST(addr, pci_config_addr, u32));
+		u32 x = inl(PCI_CONFIG_DATA);
+		if (x != 0xFFFFFFFF) {
+			print("bus: "); print_num(bus, 16, 2);
+			print(" dev: "); print_num(dev, 16, 1);
+			print(" vendor: "); print_num(x & 0xFFFF, 16, 4);
+			print(" id: "); print_num((x >> 16) & 0xFFFF, 16, 4);
+			print("\n");
+		}
+	}
+}
diff --git a/stage3/pci.h b/stage3/pci.h
new file mode 100644
index 0000000..ac893ee
--- /dev/null
+++ b/stage3/pci.h
@@ -0,0 +1,6 @@
+#ifndef PCI_H
+#define PCI_H
+
+void pci_enumerate();
+
+#endif
diff --git a/stage3/string.c b/stage3/string.c
new file mode 100644
index 0000000..ff4bfc3
--- /dev/null
+++ b/stage3/string.c
@@ -0,0 +1,56 @@
+#include "string.h"
+
+usize find_char(const char *str, char chr)
+{
+	usize ret = 0;
+	while (*str != chr && *str != '\0')
+		str++, ret++;
+	return ret;
+}
+
+u64 parse_num(u8 **str, u8 base, isize size)
+{
+	u64 x = 0;
+
+	while (size-- != 0) {
+		u8 c = **str;
+
+		u64 d;
+		if (c >= '0' && c <= '9')
+			d = c - '0';
+		else if (c >= 'a' && c <= 'z')
+			d = c - 'a';
+		else if (c >= 'A' && c <= 'z')
+			d = c - 'A';
+		else
+			return x;
+
+		if (d >= base)
+			return x;
+
+		(*str)++;
+		x = x * base + d;
+	}
+
+    return x;
+}
+
+usize strlen(const char *str)
+{
+	return find_char(str, '\0');
+}
+
+int strcmp(const char *p1, const char *p2)
+{
+	while (*p1 == *p2 && *p1 != '\0')
+		p1++, p2++;
+	return *p1 - *p2;
+}
+
+int strncmp(const char *p1, const char *p2, usize size)
+{
+	for (usize i = 0; i < size; i++)
+		if (p1[i] != p2[i])
+			return p1[i]-p2[i];
+	return 0;
+}
diff --git a/stage3/string.h b/stage3/string.h
new file mode 100644
index 0000000..2738f60
--- /dev/null
+++ b/stage3/string.h
@@ -0,0 +1,12 @@
+#ifndef STRING_H
+#define STRING_H
+
+#include "def.h"
+
+u64 parse_num(u8 **str, u8 base, isize size);
+usize find_char(const char *str, char chr);
+usize strlen(const char *str);
+int strcmp(const char *p1, const char *p2);
+int strncmp(const char *p1, const char *p2, usize size);
+
+#endif