From e5a7a87a58186f35ec41e4ea73e6c8912297f456 Mon Sep 17 00:00:00 2001
From: d0p1 <contact@d0p1.eu>
Date: Sun, 1 Sep 2024 11:53:44 +0200
Subject: [PATCH] feat(boot): loader read stpdfs root dir

---
 boot/loader/Makefile   |  3 ++-
 boot/loader/disk.inc   | 15 +++++++-----
 boot/loader/loader.asm |  5 +++-
 boot/loader/stpdfs.inc | 55 +++++++++++++++++++++++++++++++++++++++---
 4 files changed, 66 insertions(+), 12 deletions(-)

diff --git a/boot/loader/Makefile b/boot/loader/Makefile
index b164565..86a880f 100644
--- a/boot/loader/Makefile
+++ b/boot/loader/Makefile
@@ -11,7 +11,8 @@ LOADER_SRCS	= loader.asm \
 				logger.inc \
 				a20.inc \
 				multiboot.inc \
-				stpdfs.inc
+				stpdfs.inc \
+				disk.inc
 
 .PHONY: all
 all: $(TARGET)
diff --git a/boot/loader/disk.inc b/boot/loader/disk.inc
index 19339f2..c8f8e8b 100644
--- a/boot/loader/disk.inc
+++ b/boot/loader/disk.inc
@@ -7,8 +7,8 @@
 	;;   CX    - Sector count
 	;;   ES:BX - buffer 
 disk_read_sectors:
-;	test byte [bDriveLBA], TRUE
-;	je .lba_read
+	cmp byte [bDriveLBA], TRUE
+	je .lba_read
 	push ax
 	push bx
 	push cx
@@ -40,14 +40,17 @@ disk_read_sectors:
 	call bios_print
 	ret
 .lba_read:
+	push si
 	mov word [disk_packet.sectors], cx
 	mov word [disk_packet.segment], es
 	mov word [disk_packet.offset], bx
-	mov word [disk_packet.lba], ax
-	mov ds, [disk_packet]
+	mov dword [disk_packet.lba], eax
+	mov si, disk_packet
 	mov dl, [uDrive]
 	mov ah, 0x42
 	int 0x13
+	jc @b
+	pop si
 	ret
 
 C dw 0x00
@@ -59,10 +62,10 @@ disk_packet:
 	db 0
 .sectors:
 	dw 0
-.segment:
-	dw 0
 .offset:
 	dw 0
+.segment:
+	dw 0
 .lba:
 	dd 0
 	dd 0
diff --git a/boot/loader/loader.asm b/boot/loader/loader.asm
index fc3c3a8..39a92e6 100644
--- a/boot/loader/loader.asm
+++ b/boot/loader/loader.asm
@@ -46,7 +46,7 @@ _start:
 	mov dl, [uDrive]
 	cmp dl, 0x7F
 	; skip disk extension check
-	jle @f
+	jbe @f
 
 	; check disk extensions
 	mov ah, 0x41
@@ -54,6 +54,7 @@ _start:
 	int 0x13
 	jc @f
 	mov [bDriveLBA], TRUE
+
 @@:
 	; detect filesystem (FAT12/16 or StpdFS)
 	; load kernel from filesystem
@@ -261,6 +262,8 @@ _edata:
 
 boot_structure BootInfo
 
+inode_cache rb sizeof.Inode
+
 	align 4096
 boot_page_directory:
 	rb 4096
diff --git a/boot/loader/stpdfs.inc b/boot/loader/stpdfs.inc
index 3783a8c..feacb75 100644
--- a/boot/loader/stpdfs.inc
+++ b/boot/loader/stpdfs.inc
@@ -1,7 +1,7 @@
 STPDFS_NAME_MAX = 28
 
 	;; Struct: inode
-struc inode {
+struc Inode {
 	.inode   dw ?
 	.nlink   dw ?
 	.uid     dw ?
@@ -12,7 +12,7 @@ struc inode {
 	.actime  dq ?
 	.modtime dq ?
 }
-DEFN inode
+DEFN Inode
 
 	;; Struct: dirent
 struc dirent {
@@ -31,12 +31,23 @@ stpdfs_load_rootdir:
 	mov ax, 2
 	mov cx, 1
 	xor bx, bx
+
 	call disk_read_sectors
-	
+
 	; root dir is inode 1
-	mov dword eax, [DISK_BUFFER + sizeof.inode * 2 + inode.size]
+	xor ax, ax
+	mov es, ax
+	mov ecx, sizeof.Inode
+	mov esi, DISK_BUFFER + sizeof.Inode
+	mov edi, inode_cache
+	rep movsb
 
+	mov ax, DISK_BUFFER/0x10
+	mov es, ax
 
+	call stpdfs_copy_data
+
+	xchg bx, bx
 
 	ret
 
@@ -51,5 +62,41 @@ stpdfs_search:
 
 	ret
 
+	;; Function: stpdfs_copy_data
+	;;
+	;; In:
+	;;	ES  - Buffer
 stpdfs_copy_data:
+	xor edx, edx
+	mov bx, es
+	movzx ebx, bx
+@@:
+	mov ax, es
+	movzx ecx, ax
+	sub ecx, ebx
+	cmp ecx, dword [inode_cache + Inode.size]
+	jg .all_read
+
+	mov eax, edx
+	shl eax, 2
+	add eax, dword [inode_cache + Inode.zones]
+
+	push edx
+	push ebx
+	mov cx, 1
+	xor bx, bx
+	call disk_read_sectors
+	pop ebx
+	pop edx
+
+	mov ax, es
+	add ax, 512
+	mov es, ax
+	inc edx
+	cmp edx, 8
+	jbe @b
+
+.indirect_read:
+
+.all_read:
 	ret