要想看懂操作系统开始部分的代码，三个基本概念要记在心间。
第一，CPU会按照代码在内存中的地址，一条一条地自动往下执行，直到碰到跳转或者是中断。跳开一些检查保护性的代码，尽量抓到程序的主干，思路不要被打断了。
第二，是给CPU下指令时，只需要向CPU的特定寄存器写入数值即可，当特定寄存器的数值改变时，CPU就会自动执行相应的操作。
第三，是理解分段机制，在CPU进入保护模式后，所有的变量代码都会保存在固定的段中。相应地所有代码和变量的寻找都是通过段基址+段内偏移来寻址的（也就是通过线性地址来寻址）。程序中再也不会出现SCRNY EQU 0x0ff6; MOV [SCRNY],AX这样的直接寻址这样的代码了。
在多进程启动之前，大家完全可以按照单片机去理解操作系统的代码，就把CPU当成一个大号的x86单片机。毕竟多进程是操作系统区别与单片机的最显著特点。
; haribote-ipl
; TAB=4
CYLS EQU 20 ; 声明CYLS=20
ORG 0x7c00 ; 指明程序装载地址
; 标准FAT12格式软盘专用的代码 Stand FAT12 format floppy code
JMP entry
DB 0x90
DB "HARIBOTE" ; 启动扇区名称（8字节）
DW 512 ; 每个扇区（sector）大小（必须512字节）
DB 1 ; 簇（cluster）大小（必须为1个扇区）
DW 1 ; FAT起始位置（一般为第一个扇区）
DB 2 ; FAT个数（必须为2）
DW 224 ; 根目录大小（一般为224项）
DW 2880 ; 该磁盘大小（必须为2880扇区1440*1024/512）
DB 0xf0 ; 磁盘类型（必须为0xf0）
DW 9 ; FAT的长度（必??9扇区）
DW 18 ; 一个磁道（track）有几个扇区（必须为18）
DW 2 ; 磁头数（必??2）
DD 0 ; 不使用分区，必须是0
DD 2880 ; 重写一次磁盘大小
DB 0,0,0x29 ; 意义不明（固定）
DD 0xffffffff ; （可能是）卷标号码
DB "HARIBOTEOS " ; 磁盘的名称（必须为11字?，不足填空格）
DB "FAT12 " ; 磁盘格式名称（必??8字?，不足填空格）
RESB 18 ; 先空出18字节
; 程序主体
entry:
MOV AX,0 ; 初始化寄存器
MOV SS,AX
MOV SP,0x7c00
MOV DS,AX
; 读取磁盘
MOV AX,0x0820
MOV ES,AX
MOV CH,0 ; 柱面0
MOV DH,0 ; 磁头0
MOV CL,2 ; 扇区2
readloop:
MOV SI,0 ; 记录失败次数寄存器
retry:
MOV AH,0x02 ; AH=0x02 : 读入磁盘
MOV AL,1 ; 1个扇区
MOV BX,0
MOV DL,0x00 ; A驱动器
INT 0x13 ; 调用磁盘BIOS
JNC next ; 没出错则跳转到fin
ADD SI,1 ; 往SI加1
CMP SI,5 ; 比较SI与5
JAE error ; SI >= 5 跳转到error
MOV AH,0x00
MOV DL,0x00 ; A驱动器
INT 0x13 ; 重置驱动器
JMP retry
next:
MOV AX,ES ; 把内存地址后移0x200（512/16十六进制转换）
ADD AX,0x0020
MOV ES,AX ; ADD ES,0x020因为没有ADD ES，只能通过AX进行
ADD CL,1 ; 往CL里面加1
CMP CL,18 ; 比较CL与18
JBE readloop ; CL <= 18 跳转到readloop
MOV CL,1
ADD DH,1
CMP DH,2
JB readloop ; DH < 2 跳转到readloop
MOV DH,0
ADD CH,1
CMP CH,CYLS
JB readloop ; CH < CYLS 跳转到readloop
; 读取完毕，跳转到haribote.sys执行！
MOV [0x0ff0],CH ; 记录IPL实际读取了多少内容
JMP 0xc200
error:
MOV AX,0
MOV ES,AX
MOV SI,msg
putloop:
MOV AL,[SI]
ADD SI,1 ; 给SI加1
CMP AL,0
JE fin
MOV AH,0x0e ; 显示一个文字
MOV BX,15 ; 指定字符颜色
INT 0x10 ; 调用显卡BIOS
JMP putloop
fin:
HLT ; 让CPU停止，等待指令
JMP fin ; 无限循环
msg:
DB 0x0a, 0x0a ; 换行两次
DB "load error"
DB 0x0a ; 换行
DB 0
RESB 0x7dfe-$ ; 填写0x00直到0x001fe
DB 0x55, 0xaa
; haribote-os boot asm
; TAB=4
[INSTRSET "i486p"]
VBEMODE EQU 0x105 ; 1024 x 768 x 8bit 彩色
; 显示模式
; 0x100 : 640 x 400 x 8bit 彩色
; 0x101 : 640 x 480 x 8bit 彩色
; 0x103 : 800 x 600 x 8bit 彩色
; 0x105 : 1024 x 768 x 8bit 彩色
; 0x107 : 1280 x 1024 x 8bit 彩色
BOTPAK EQU 0x00280000 ; 加载bootpack
DSKCAC EQU 0x00100000 ; 磁盘缓存的位置
DSKCAC0 EQU 0x00008000 ; 磁盘缓存的位置（实模式）
; BOOT_INFO 相关
CYLS EQU 0x0ff0 ; 引导扇区设置
LEDS EQU 0x0ff1
VMODE EQU 0x0ff2 ; 关于颜色的信息
SCRNX EQU 0x0ff4 ; 分辨率X
SCRNY EQU 0x0ff6 ; 分辨率Y
VRAM EQU 0x0ff8 ; 图像缓冲区的起始地址
ORG 0xc200 ; 这个的程序要被装载的内存地址
; 确认VBE是否存在
MOV AX,0x9000
MOV ES,AX
MOV DI,0
MOV AX,0x4f00
INT 0x10
CMP AX,0x004f
JNE scrn320
; 检查VBE的版本
MOV AX,[ES:DI+4]
CMP AX,0x0200
JB scrn320 ; if (AX < 0x0200) goto scrn320
; 取得画面模式信息
MOV CX,VBEMODE
MOV AX,0x4f01
INT 0x10
CMP AX,0x004f
JNE scrn320
; 画面模式信息的确认
CMP BYTE [ES:DI+0x19],8 ;颜色数必须为8
JNE scrn320
CMP BYTE [ES:DI+0x1b],4 ;颜色的指定方法必须为4(4是调色板模式)
JNE scrn320
MOV AX,[ES:DI+0x00] ;模式属性bit7不是1就不能加上0x4000
AND AX,0x0080
JZ scrn320 ; 模式属性的bit7是0，所以放弃
; 画面设置
MOV BX,VBEMODE+0x4000
MOV AX,0x4f02
INT 0x10
MOV BYTE [VMODE],8 ; 屏幕的模式（参考C语言的引用）
MOV AX,[ES:DI+0x12]
MOV [SCRNX],AX
MOV AX,[ES:DI+0x14]
MOV [SCRNY],AX
MOV EAX,[ES:DI+0x28] ;VRAM的地址
MOV [VRAM],EAX
JMP keystatus
scrn320:
MOV AL,0x13 ; VGA图、320x200x8bit彩色
MOV AH,0x00
INT 0x10
MOV BYTE [VMODE],8 ; 记下画面模式（参考C语言）
MOV WORD [SCRNX],320
MOV WORD [SCRNY],200
MOV DWORD [VRAM],0x000a0000
; 通过 BIOS 获取指示灯状态
keystatus:
MOV AH,0x02
INT 0x16 ; keyboard BIOS
MOV [LEDS],AL
; PIC关闭一切中断
; 根据AT兼容机的规格，如果要初始化PIC，
; 必须在CLI之前进行，否则有时会挂起。
; 随后进行PIC的初始化。
MOV AL,0xff
OUT 0x21,AL
NOP ; 如果连续执行OUT指令，有些机种会无法正常运行
OUT 0xa1,AL
CLI ; 禁止CPU级别的中断
; 为了让CPU能够访问1MB以上的内存空间，设定A20GATE
CALL waitkbdout
MOV AL,0xd1
OUT 0x64,AL
CALL waitkbdout
MOV AL,0xdf ; enable A20
OUT 0x60,AL
CALL waitkbdout
; 切换到保护模式
[INSTRSET "i486p"] ; 说明使用486指令
LGDT [GDTR0] ; 设置临时GDT
MOV EAX,CR0
AND EAX,0x7fffffff ; 设bit31为0（禁用分页）
OR EAX,0x00000001 ; bit0到1转换（保护模式过渡）
MOV CR0,EAX
JMP pipelineflush
pipelineflush:
MOV AX,1*8 ; 可读写的段 32bit
MOV DS,AX
MOV ES,AX
MOV FS,AX
MOV GS,AX
MOV SS,AX
; bootpack传递
MOV ESI,bootpack ; 转送源
MOV EDI,BOTPAK ; 转送目标
MOV ECX,512*1024/4
CALL memcpy
; 磁盘数据最终转送到它本来的位置去
; 首先从启动扇区开始
MOV ESI,0x7c00 ; 转送源
MOV EDI,DSKCAC ; 转送目标
MOV ECX,512/4
CALL memcpy
; 剩余的全部
MOV ESI,DSKCAC0+512 ; 转送源
MOV EDI,DSKCAC+512 ; 转送源目标
MOV ECX,0
MOV CL,BYTE [CYLS]
IMUL ECX,512*18*2/4 ; 从柱面数变换为字节数/4
SUB ECX,512/4 ; 减去 IPL 偏移量
CALL memcpy
; 必须由asmhead来完成的工作，至此全部完毕
; 以后就交由bootpack来完成
; bootpack启动
MOV EBX,BOTPAK
MOV ECX,[EBX+16]
ADD ECX,3 ; ECX += 3;
SHR ECX,2 ; ECX /= 4;
JZ skip ; 没有要转送的东西时
MOV ESI,[EBX+20] ; 转送源
ADD ESI,EBX
MOV EDI,[EBX+12] ; 转送目标
CALL memcpy
skip:
MOV ESP,[EBX+12] ; 堆栈的初始化
JMP DWORD 2*8:0x0000001b
waitkbdout:
IN AL,0x64
AND AL,0x02
JNZ waitkbdout ; AND的结果如果不是0，就跳到waitkbdout
RET
memcpy:
MOV EAX,[ESI]
ADD ESI,4
MOV [EDI],EAX
ADD EDI,4
SUB ECX,1
JNZ memcpy ; 减法运算的结果如果不是0，就跳转到memcpy
RET
; memcpy地址前缀大小
ALIGNB 16
GDT0:
RESB 8 ; 初始值
DW 0xffff,0x0000,0x9200,0x00cf ; 可以读写的段（segment）32bit
DW 0xffff,0x0000,0x9a28,0x0047 ; 可执行的文件的32bit寄存器（bootpack用）
DW 0
GDTR0:
DW 8*3-1
DD GDT0
ALIGNB 16
bootpack:
/* bootpack */
#include "bootpack.h"
#include <stdio.h>
#define KEYCMD_LED 0xed
void keywin_off(struct SHEET *key_win);
void keywin_on(struct SHEET *key_win);
void close_console(struct SHEET *sht);
void close_constask(struct TASK *task);
void HariMain(void)
{
struct BOOTINFO *binfo = (struct BOOTINFO *) ADR_BOOTINFO;
struct SHTCTL *shtctl;
char s[40];
struct FIFO32 fifo, keycmd;//定义了两个类型为struct FIFO32的队列:fifo和keycmd
int fifobuf[128], keycmd_buf[32];
int mx, my, i, new_mx = -1, new_my = 0, new_wx = 0x7fffffff, new_wy = 0;
unsigned int memtotal;
struct MOUSE_DEC mdec;
struct MEMMAN *memman = (struct MEMMAN *) MEMMAN_ADDR;
unsigned char *buf_back, buf_mouse[256];
struct SHEET *sht_back, *sht_mouse;
struct TASK *task_a, *task;
static char keytable0[0x80] = {
0, 0, '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '-', '^', 0x08, 0,
'Q', 'W', 'E', 'R', 'T', 'Y', 'U', 'I', 'O', 'P', '@', '[', 0x0a, 0, 'A', 'S',
'D', 'F', 'G', 'H', 'J', 'K', 'L', ';', ':', 0, 0, ']', 'Z', 'X', 'C', 'V',
'B', 'N', 'M', ',', '.', '/', 0, '*', 0, ' ', 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, '7', '8', '9', '-', '4', '5', '6', '+', '1',
'2', '3', '0', '.', 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0x5c, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x5c, 0, 0
};
static char keytable1[0x80] = {
0, 0, '!', 0x22, '#', '$', '%', '&', 0x27, '(', ')', '~', '=', '~', 0x08, 0,
'Q', 'W', 'E', 'R', 'T', 'Y', 'U', 'I', 'O', 'P', '`', '{', 0x0a, 0, 'A', 'S',
'D', 'F', 'G', 'H', 'J', 'K', 'L', '+', '*', 0, 0, '}', 'Z', 'X', 'C', 'V',
'B', 'N', 'M', '<', '>', '?', 0, '*', 0, ' ', 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, '7', '8', '9', '-', '4', '5', '6', '+', '1',
'2', '3', '0', '.', 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, '_', 0, 0, 0, 0, 0, 0, 0, 0, 0, '|', 0, 0
};
int key_shift = 0, key_leds = (binfo->leds >> 4) & 7, keycmd_wait = -1;
int j, x, y, mmx = -1, mmy = -1, mmx2 = 0;
struct SHEET *sht = 0, *key_win, *sht2;
int *fat;
unsigned char *nihongo;
struct FILEINFO *finfo;
extern char hankaku[4096];
init_gdtidt();
init_pic();
io_sti(); /* IDT/PIC的初始化已经完成，于是开放CPU的中断 */
fifo32_init(&fifo, 128, fifobuf, 0);
*((int *) 0x0fec) = (int) &fifo;
init_pit();
init_keyboard(&fifo, 256);
enable_mouse(&fifo, 512, &mdec);
io_out8(PIC0_IMR, 0xf8); /* 设定PIT和PIC1以及键盘为许可(11111000) */
io_out8(PIC1_IMR, 0xef); /* 开放鼠标中断(11101111) */
fifo32_init(&keycmd, 32, keycmd_buf, 0);
memtotal = memtest(0x00400000, 0xbfffffff);
memman_init(memman);
memman_free(memman, 0x00001000, 0x0009e000); /* 0x00001000 - 0x0009efff */
memman_free(memman, 0x00400000, memtotal - 0x00400000);
init_palette();
shtctl = shtctl_init(memman, binfo->vram, binfo->scrnx, binfo->scrny);
task_a = task_init(memman);
fifo.task = task_a;
task_run(task_a, 1, 2);
*((int *) 0x0fe4) = (int) shtctl;
task_a->langmode = 0;
/* sht_back */
sht_back = sheet_alloc(shtctl);
buf_back = (unsigned char *) memman_alloc_4k(memman, binfo->scrnx * binfo->scrny);
sheet_setbuf(sht_back, buf_back, binfo->scrnx, binfo->scrny, -1); /* 无透明色 */
init_screen8(buf_back, binfo->scrnx, binfo->scrny);
/* sht_cons */
key_win = open_console(shtctl, memtotal);
/* sht_mouse */
sht_mouse = sheet_alloc(shtctl);
sheet_setbuf(sht_mouse, buf_mouse, 16, 16, 99);
init_mouse_cursor8(buf_mouse, 99);
mx = (binfo->scrnx - 16) / 2; /* 计算坐标使其位于画面中央 */
my = (binfo->scrny - 28 - 16) / 2;
sheet_slide(sht_back, 0, 0);
sheet_slide(key_win, 32, 4);
sheet_slide(sht_mouse, mx, my);
sheet_updown(sht_back, 0);
sheet_updown(key_win, 1);
sheet_updown(sht_mouse, 2);
keywin_on(key_win);
/* 为了避免和键盘当前状态冲突，在一开始先进行设置 */
fifo32_put(&keycmd, KEYCMD_LED);
fifo32_put(&keycmd, key_leds);
/* 载入nihongo.fnt */
fat = (int *) memman_alloc_4k(memman, 4 * 2880);
file_readfat(fat, (unsigned char *) (ADR_DISKIMG + 0x000200));
finfo = file_search("nihongo.fnt", (struct FILEINFO *) (ADR_DISKIMG + 0x002600), 224);
if (finfo != 0) {
i = finfo->size;
nihongo = file_loadfile2(finfo->clustno, &i, fat);
} else {
nihongo = (unsigned char *) memman_alloc_4k(memman, 16 * 256 + 32 * 94 * 47);
for (i = 0; i < 16 * 256; i++) {
nihongo[i] = hankaku[i]; /*没有字库，半角部分直接复制英文字库*/
}
for (i = 16 * 256; i < 16 * 256 + 32 * 94 * 47; i++) {
nihongo[i] = 0xff; /* 没有字库，全角部分以0xff填充 */
}
}
*((int *) 0x0fe8) = (int) nihongo;
memman_free_4k(memman, (int) fat, 4 * 2880);
for (;;) {
if (fifo32_status(&keycmd) > 0 && keycmd_wait < 0) {
/* 如果存在向键盘控制器发送的数据，则发送它 */
keycmd_wait = fifo32_get(&keycmd);
wait_KBC_sendready();
io_out8(PORT_KEYDAT, keycmd_wait);
}
io_cli();
if (fifo32_status(&fifo) == 0) {
/* FIFO为空，当存在搁置的绘图操作时立即执行*/
if (new_mx >= 0) {
io_sti();
sheet_slide(sht_mouse, new_mx, new_my);
new_mx = -1;
} else if (new_wx != 0x7fffffff) {
io_sti();
sheet_slide(sht, new_wx, new_wy);
new_wx = 0x7fffffff;
} else {
task_sleep(task_a);
io_sti();
}
} else {
i = fifo32_get(&fifo);
io_sti();
if (key_win != 0 && key_win->flags == 0) { /*窗口被关闭*/
if (shtctl->top == 1) { /*当画面上只剩鼠标和背景时*/
key_win = 0;
} else {
key_win = shtctl->sheets[shtctl->top - 1];
keywin_on(key_win);
}
}
if (256 <= i && i <= 511) { /* 键盘数据*/
if (i < 0x80 + 256) { /*将按键编码转换为字符编码*/
if (key_shift == 0) {
s[0] = keytable0[i - 256];
} else {
s[0] = keytable1[i - 256];
}
} else {
s[0] = 0;
}
if ('A' <= s[0] && s[0] <= 'Z') { /*当输入字符为英文字母时*/
if (((key_leds & 4) == 0 && key_shift == 0) ||
((key_leds & 4) != 0 && key_shift != 0)) {
s[0] += 0x20; /*将大写字母转换为小写字母*/
}
}
if (s[0] != 0 && key_win != 0) { /*一般字符、退格键、回车键*/
fifo32_put(&key_win->task->fifo, s[0] + 256);
}
if (i == 256 + 0x0f && key_win != 0) { /* Tab键 */
keywin_off(key_win);
j = key_win->height - 1;
if (j == 0) {
j = shtctl->top - 1;
}
key_win = shtctl->sheets[j];
keywin_on(key_win);
}
if (i == 256 + 0x2a) { /*左Shift ON */
key_shift |= 1;
}
if (i == 256 + 0x36) { /*右Shift ON */
key_shift |= 2;
}
if (i == 256 + 0xaa) { /*左Shift OFF */
key_shift &= ~1;
}
if (i == 256 + 0xb6) { /*右Shift OFF */
key_shift &= ~2;
}
if (i == 256 + 0x3a) { /* CapsLock */
key_leds ^= 4;
fifo32_put(&keycmd, KEYCMD_LED);
fifo32_put(&keycmd, key_leds);
}
if (i == 256 + 0x45) { /* NumLock */
key_leds ^= 2;
fifo32_put(&keycmd, KEYCMD_LED);
fifo32_put(&keycmd, key_leds);
}
if (i == 256 + 0x46) { /* ScrollLock */
key_leds ^= 1;
fifo32_put(&keycmd, KEYCMD_LED);
fifo32_put(&keycmd, key_leds);
}
if (i == 256 + 0x3b && key_shift != 0 && key_win != 0) { /* Shift+F1 */
task = key_win->task;
if (task != 0 && task->tss.ss0 != 0) {
cons_putstr0(task->cons, "\nBreak(key) :\n");
io_cli(); /*强制结束处理时禁止任务切换*/
task->tss.eax = (int) &(task->tss.esp0);
task->tss.eip = (int) asm_end_app;
io_sti();
task_run(task, -1, 0); /*为了确实执行结束处理，如果处于休眠状态则唤醒*/
}
}
if (i == 256 + 0x3c && key_shift != 0) { /* Shift+F2 */
if (key_win != 0) {
keywin_off(key_win);
}
key_win = open_console(shtctl, memtotal);
sheet_slide(key_win, 32, 4);
sheet_updown(key_win, shtctl->top);
keywin_on(key_win);
}
if (i == 256 + 0x57) { /* F11 */
sheet_updown(shtctl->sheets[1], shtctl->top - 1);
}
if (i == 256 + 0xfa) { /*键盘成功接收到数据*/
keycmd_wait = -1;
}
if (i == 256 + 0xfe) { /*键盘没有成功接收到数据*/
wait_KBC_sendready();
io_out8(PORT_KEYDAT, keycmd_wait);
}
} else if (512 <= i && i <= 767) { /* 鼠标数据*/
if (mouse_decode(&mdec, i - 512) != 0) {
/* 已经收集了3字节的数据，移动光标 */
mx += mdec.x;
my += mdec.y;
if (mx < 0) {
mx = 0;
}
if (my < 0) {
my = 0;
}
if (mx > binfo->scrnx - 1) {
mx = binfo->scrnx - 1;
}
if (my > binfo->scrny - 1) {
my = binfo->scrny - 1;
}
new_mx = mx;
new_my = my;
if ((mdec.btn & 0x01) != 0) { /* 按下左键 */
if (mmx < 0) {
/*如果处于通常模式*/
/*按照从上到下的顺序寻找鼠标所指向的图层*/
for (j = shtctl->top - 1; j > 0; j--) {
sht = shtctl->sheets[j];
x = mx - sht->vx0;
y = my - sht->vy0;
if (0 <= x && x < sht->bxsize && 0 <= y && y < sht->bysize) {
if (sht->buf[y * sht->bxsize + x] != sht->col_inv) {
sheet_updown(sht, shtctl->top - 1);
if (sht != key_win) {
keywin_off(key_win);
key_win = sht;
keywin_on(key_win);
}
if (3 <= x && x < sht->bxsize - 3 && 3 <= y && y < 21) {
mmx = mx; /*进入窗口移动模式*/
mmy = my;
mmx2 = sht->vx0;
new_wy = sht->vy0;
}
if (sht->bxsize - 21 <= x && x < sht->bxsize - 5 && 5 <= y && y < 19) {
/*点击“×”按钮*/
if ((sht->flags & 0x10) != 0) { /*该窗口是否为应用程序窗口？*/
task = sht->task;
cons_putstr0(task->cons, "\nBreak(mouse) :\n");
io_cli(); /*强制结束处理时禁止任务切换*/
task->tss.eax = (int) &(task->tss.esp0);
task->tss.eip = (int) asm_end_app;
io_sti();
task_run(task, -1, 0);
} else { /*命令行窗口*/
task = sht->task;
sheet_updown(sht, -1); /*暂且隐藏该图层*/
keywin_off(key_win);
key_win = shtctl->sheets[shtctl->top - 1];
keywin_on(key_win);
io_cli();
fifo32_put(&task->fifo, 4);
io_sti();
}
}
break;
}
}
}
} else {
/*如果处于窗口移动模式*/
x = mx - mmx; /*计算鼠标指针移动量*/
y = my - mmy;
new_wx = (mmx2 + x + 2) & ~3;
new_wy = new_wy + y;
mmy = my;
}
} else {
/*没有按下左键*/
mmx = -1; /*切换到一般模式*/
if (new_wx != 0x7fffffff) {
sheet_slide(sht, new_wx, new_wy); /*固定图层位置*/
new_wx = 0x7fffffff;
}
}
}
} else if (768 <= i && i <= 1023) { /*命令行窗口关闭处理*/
close_console(shtctl->sheets0 + (i - 768));
} else if (1024 <= i && i <= 2023) {
close_constask(taskctl->tasks0 + (i - 1024));
} else if (2024 <= i && i <= 2279) { /*只关闭命令行窗口*/
sht2 = shtctl->sheets0 + (i - 2024);
memman_free_4k(memman, (int) sht2->buf, 256 * 165);
sheet_free(sht2);
}
}
}
}
void keywin_off(struct SHEET *key_win)
{
change_wtitle8(key_win, 0);
if ((key_win->flags & 0x20) != 0) {
fifo32_put(&key_win->task->fifo, 3); /*命令行窗口光标OFF */
}
return;
}
void keywin_on(struct SHEET *key_win)
{
change_wtitle8(key_win, 1);
if ((key_win->flags & 0x20) != 0) {
fifo32_put(&key_win->task->fifo, 2); /*命令行窗口光标ON */
}
return;
}
struct TASK *open_constask(struct SHEET *sht, unsigned int memtotal)
{
struct MEMMAN *memman = (struct MEMMAN *) MEMMAN_ADDR;
struct TASK *task = task_alloc();
int *cons_fifo = (int *) memman_alloc_4k(memman, 128 * 4);
task->cons_stack = memman_alloc_4k(memman, 64 * 1024);
task->tss.esp = task->cons_stack + 64 * 1024 - 12;
task->tss.eip = (int) &console_task;
task->tss.es = 1 * 8;
task->tss.cs = 2 * 8;
task->tss.ss = 1 * 8;
task->tss.ds = 1 * 8;
task->tss.fs = 1 * 8;
task->tss.gs = 1 * 8;
*((int *) (task->tss.esp + 4)) = (int) sht;
*((int *) (task->tss.esp + 8)) = memtotal;
task_run(task, 2, 2); /* level=2, priority=2 */
fifo32_init(&task->fifo, 128, cons_fifo, task);
return task;
}
struct SHEET *open_console(struct SHTCTL *shtctl, unsigned int memtotal)
{
struct MEMMAN *memman = (struct MEMMAN *) MEMMAN_ADDR;
struct SHEET *sht = sheet_alloc(shtctl);
unsigned char *buf = (unsigned char *) memman_alloc_4k(memman, 256 * 165);
sheet_setbuf(sht, buf, 256, 165, -1); /*无透明色*/
make_window8(buf, 256, 165, "console", 0);
make_textbox8(sht, 8, 28, 240, 128, COL8_000000);
sht->task = open_constask(sht, memtotal);
sht->flags |= 0x20; /*有光标*/
return sht;
}
void close_constask(struct TASK *task)
{
struct MEMMAN *memman = (struct MEMMAN *) MEMMAN_ADDR;
task_sleep(task);
memman_free_4k(memman, task->cons_stack, 64 * 1024);
memman_free_4k(memman, (int) task->fifo.buf, 128 * 4);
task->flags = 0; /*用来替代task_free(task); */
return;
}
void close_console(struct SHEET *sht)
{
struct MEMMAN *memman = (struct MEMMAN *) MEMMAN_ADDR;
struct TASK *task = sht->task;
memman_free_4k(memman, (int) sht->buf, 256 * 165);
sheet_free(sht);
close_constask(task);
return;
}
/* GDT、IDT、descriptor table 关系处理 */
#include "bootpack.h"
void init_gdtidt(void)
{
struct SEGMENT_DESCRIPTOR *gdt = (struct SEGMENT_DESCRIPTOR *) ADR_GDT;
struct GATE_DESCRIPTOR *idt = (struct GATE_DESCRIPTOR *) ADR_IDT;
int i;
/* GDT初始化 */
for (i = 0; i <= LIMIT_GDT / 8; i++) {
set_segmdesc(gdt + i, 0, 0, 0);
}
set_segmdesc(gdt + 1, 0xffffffff, 0x00000000, AR_DATA32_RW);
set_segmdesc(gdt + 2, LIMIT_BOTPAK, ADR_BOTPAK, AR_CODE32_ER);
load_gdtr(LIMIT_GDT, ADR_GDT);
/* IDT初始化 */
for (i = 0; i <= LIMIT_IDT / 8; i++) {
set_gatedesc(idt + i, 0, 0, 0);
}
load_idtr(LIMIT_IDT, ADR_IDT);
/* IDT设置*/
set_gatedesc(idt + 0x0c, (int) asm_inthandler0c, 2 * 8, AR_INTGATE32);
set_gatedesc(idt + 0x0d, (int) asm_inthandler0d, 2 * 8, AR_INTGATE32);
set_gatedesc(idt + 0x20, (int) asm_inthandler20, 2 * 8, AR_INTGATE32);
set_gatedesc(idt + 0x21, (int) asm_inthandler21, 2 * 8, AR_INTGATE32);
set_gatedesc(idt + 0x2c, (int) asm_inthandler2c, 2 * 8, AR_INTGATE32);
set_gatedesc(idt + 0x40, (int) asm_hrb_api, 2 * 8, AR_INTGATE32 + 0x60);
return;
}
void set_segmdesc(struct SEGMENT_DESCRIPTOR *sd, unsigned int limit, int base, int ar)
{
if (limit > 0xfffff) {
ar |= 0x8000; /* G_bit = 1 */
limit /= 0x1000;
}
sd->limit_low = limit & 0xffff;
sd->base_low = base & 0xffff;
sd->base_mid = (base >> 16) & 0xff;
sd->access_right = ar & 0xff;
sd->limit_high = ((limit >> 16) & 0x0f) | ((ar >> 8) & 0xf0);
sd->base_high = (base >> 24) & 0xff;
return;
}
void set_gatedesc(struct GATE_DESCRIPTOR *gd, int offset, int selector, int ar)
{
gd->offset_low = offset & 0xffff;
gd->selector = selector;
gd->dw_count = (ar >> 8) & 0xff;
gd->access_right = ar & 0xff;
gd->offset_high = (offset >> 16) & 0xffff;
return;
}
/* FIFO */
#include "bootpack.h"
#define FLAGS_OVERRUN 0x0001
void fifo32_init(struct FIFO32 *fifo, int size, int *buf, struct TASK *task)
/* FIFO缓冲区的初始化*/
{
fifo->size = size;
fifo->buf = buf;
fifo->free = size; /*空*/
fifo->flags = 0;
fifo->p = 0; /*写入位置*/
fifo->q = 0; /*读取位置*/
fifo->task = task; /*有数据写入时需要唤醒的任务*/
return;
}
int fifo32_put(struct FIFO32 *fifo, int data)
/*向FIFO写入数据并累积起来*/
{
if (fifo->free == 0) {
/*没有空余空间，溢出*/
fifo->flags |= FLAGS_OVERRUN;
return -1;
}
fifo->buf[fifo->p] = data;
fifo->p++;
if (fifo->p == fifo->size) {
fifo->p = 0;
}
fifo->free--;
if (fifo->task != 0) {
if (fifo->task->flags != 2) { /*如果任务处于休眠状态*/
task_run(fifo->task, -1, 0); /*将任务唤醒*/
}
}
return 0;
}
int fifo32_get(struct FIFO32 *fifo)
/*从FIFO取得一个数据*/
{
int data;
if (fifo->free == fifo->size) {
/*当缓冲区为空的情况下返回-1*/
return -1;
}
data = fifo->buf[fifo->q];
fifo->q++;
if (fifo->q == fifo->size) {
fifo->q = 0;
}
fifo->free++;
return data;
}
int fifo32_status(struct FIFO32 *fifo)
/*报告已经存储了多少数据*/
{
return fifo->size - fifo->free;
}
/* asmhead.nas */
struct BOOTINFO { /* 0x0ff0-0x0fff */
char cyls; /* 启动区读磁盘读到此为止 */
char leds; /* 启动时键盘的LED的状态 */
char vmode; /* 显卡模式为多少位彩色 */
char reserve;
short scrnx, scrny; /* 画面分辨率 */
char *vram;
};
#define ADR_BOOTINFO 0x00000ff0
#define ADR_DISKIMG 0x00100000
/* naskfunc.nas */
void io_hlt(void);
void io_cli(void);
void io_sti(void);
void io_stihlt(void);
int io_in8(int port);
void io_out8(int port, int data);
int io_load_eflags(void);
void io_store_eflags(int eflags);
void load_gdtr(int limit, int addr);
void load_idtr(int limit, int addr);
int load_cr0(void);
void store_cr0(int cr0);
void load_tr(int tr);
void asm_inthandler0c(void);
void asm_inthandler0d(void);
void asm_inthandler20(void);
void asm_inthandler21(void);
void asm_inthandler2c(void);
unsigned int memtest_sub(unsigned int start, unsigned int end);
void farjmp(int eip, int cs);
void farcall(int eip, int cs);
void asm_hrb_api(void);
void start_app(int eip, int cs, int esp, int ds, int *tss_esp0);
void asm_end_app(void);
/* fifo.c */
struct FIFO32 {
int *buf;
int p, q, size, free, flags;
struct TASK *task;
};
void fifo32_init(struct FIFO32 *fifo, int size, int *buf, struct TASK *task);
int fifo32_put(struct FIFO32 *fifo, int data);
int fifo32_get(struct FIFO32 *fifo);
int fifo32_status(struct FIFO32 *fifo);
/* graphic.c */
void init_palette(void);
void set_palette(int start, int end, unsigned char *rgb);
void boxfill8(unsigned char *vram, int xsize, unsigned char c, int x0, int y0, int x1, int y1);
void init_screen8(char *vram, int x, int y);
void putfont8(char *vram, int xsize, int x, int y, char c, char *font);
void putfonts8_asc(char *vram, int xsize, int x, int y, char c, unsigned char *s);
void init_mouse_cursor8(char *mouse, char bc);
void putblock8_8(char *vram, int vxsize, int pxsize,
int pysize, int px0, int py0, char *buf, int bxsize);
#define COL8_000000 0
#define COL8_FF0000 1
#define COL8_00FF00 2
#define COL8_FFFF00 3
#define COL8_0000FF 4
#define COL8_FF00FF 5
#define COL8_00FFFF 6
#define COL8_FFFFFF 7
#define COL8_C6C6C6 8
#define COL8_840000 9
#define COL8_008400 10
#define COL8_848400 11
#define COL8_000084 12
#define COL8_840084 13
#define COL8_008484 14
#define COL8_848484 15
/* dsctbl.c */
struct SEGMENT_DESCRIPTOR {
short limit_low, base_low;
char base_mid, access_right;
char limit_high, base_high;
};
struct GATE_DESCRIPTOR {
short offset_low, selector;
char dw_count, access_right;
short offset_high;
};
void init_gdtidt(void);
void set_segmdesc(struct SEGMENT_DESCRIPTOR *sd, unsigned int limit, int base, int ar);
void set_gatedesc(struct GATE_DESCRIPTOR *gd, int offset, int selector, int ar);
#define ADR_IDT 0x0026f800
#define LIMIT_IDT 0x000007ff
#define ADR_GDT 0x00270000
#define LIMIT_GDT 0x0000ffff
#define ADR_BOTPAK 0x00280000
#define LIMIT_BOTPAK 0x0007ffff
#define AR_DATA32_RW 0x4092
#define AR_CODE32_ER 0x409a
#define AR_LDT 0x0082
#define AR_TSS32 0x0089
#define AR_INTGATE32 0x008e
/* int.c */
void init_pic(void);
#define PIC0_ICW1 0x0020
#define PIC0_OCW2 0x0020
#define PIC0_IMR 0x0021
#define PIC0_ICW2 0x0021
#define PIC0_ICW3 0x0021
#define PIC0_ICW4 0x0021
#define PIC1_ICW1 0x00a0
#define PIC1_OCW2 0x00a0
#define PIC1_IMR 0x00a1
#define PIC1_ICW2 0x00a1
#define PIC1_ICW3 0x00a1
#define PIC1_ICW4 0x00a1
/* keyboard.c */
void inthandler21(int *esp);
void wait_KBC_sendready(void);
void init_keyboard(struct FIFO32 *fifo, int data0);
#define PORT_KEYDAT 0x0060
#define PORT_KEYCMD 0x0064
/* mouse.c */
struct MOUSE_DEC {
unsigned char buf[3], phase;
int x, y, btn;
};
void inthandler2c(int *esp);
void enable_mouse(struct FIFO32 *fifo, int data0, struct MOUSE_DEC *mdec);
int mouse_decode(struct MOUSE_DEC *mdec, unsigned char dat);
/* memory.c */
#define MEMMAN_FREES 4090 /* ����?�32KB */
#define MEMMAN_ADDR 0x003c0000
struct FREEINFO { /* ������� */
unsigned int addr, size;
};
struct MEMMAN { /* �������ǘ� */
int frees, maxfrees, lostsize, losts;
struct FREEINFO free[MEMMAN_FREES];
};
unsigned int memtest(unsigned int start, unsigned int end);
void memman_init(struct MEMMAN *man);
unsigned int memman_total(struct MEMMAN *man);
unsigned int memman_alloc(struct MEMMAN *man, unsigned int size);
int memman_free(struct MEMMAN *man, unsigned int addr, unsigned int size);
unsigned int memman_alloc_4k(struct MEMMAN *man, unsigned int size);
int memman_free_4k(struct MEMMAN *man, unsigned int addr, unsigned int size);
/* sheet.c */
#define MAX_SHEETS 256
struct SHEET {
unsigned char *buf;
int bxsize, bysize, vx0, vy0, col_inv, height, flags;
struct SHTCTL *ctl;
struct TASK *task;
};
struct SHTCTL {
unsigned char *vram, *map;
int xsize, ysize, top;
struct SHEET *sheets[MAX_SHEETS];
struct SHEET sheets0[MAX_SHEETS];
};
struct SHTCTL *shtctl_init(struct MEMMAN *memman, unsigned char *vram, int xsize, int ysize);
struct SHEET *sheet_alloc(struct SHTCTL *ctl);
void sheet_setbuf(struct SHEET *sht, unsigned char *buf, int xsize, int ysize, int col_inv);
void sheet_updown(struct SHEET *sht, int height);
void sheet_refresh(struct SHEET *sht, int bx0, int by0, int bx1, int by1);
void sheet_slide(struct SHEET *sht, int vx0, int vy0);
void sheet_free(struct SHEET *sht);
/* timer.c */
#define MAX_TIMER 500
struct TIMER {
struct TIMER *next;
unsigned int timeout;
char flags, flags2;
struct FIFO32 *fifo;
int data;
};
struct TIMERCTL {
unsigned int count, next;
struct TIMER *t0;
struct TIMER timers0[MAX_TIMER];
};
extern struct TIMERCTL timerctl;
void init_pit(void);
struct TIMER *timer_alloc(void);
void timer_free(struct TIMER *timer);
void timer_init(struct TIMER *timer, struct FIFO32 *fifo, int data);
void timer_settime(struct TIMER *timer, unsigned int timeout);
void inthandler20(int *esp);
int timer_cancel(struct TIMER *timer);
void timer_cancelall(struct FIFO32 *fifo);
/* mtask.c */
#define MAX_TASKS 1000 /*最大任务数量*/
#define TASK_GDT0 3 /*定义从GDT的几号开始分配给TSS */
#define MAX_TASKS_LV 100
#define MAX_TASKLEVELS 10
struct TSS32 {
int backlink, esp0, ss0, esp1, ss1, esp2, ss2, cr3;
int eip, eflags, eax, ecx, edx, ebx, esp, ebp, esi, edi;
int es, cs, ss, ds, fs, gs;
int ldtr, iomap;
};
struct TASK {
int sel, flags; /* sel用来存放GDT的编号*/
int level, priority; /* 优先级 */
struct FIFO32 fifo;
struct TSS32 tss;
struct SEGMENT_DESCRIPTOR ldt[2];
struct CONSOLE *cons;
int ds_base, cons_stack;
struct FILEHANDLE *fhandle;
int *fat;
char *cmdline;
unsigned char langmode, langbyte1;
};
struct TASKLEVEL {
int running; /*正在运行的任务数量*/
int now; /*这个变量用来记录当前正在运行的是哪个任务*/
struct TASK *tasks[MAX_TASKS_LV];
};
struct TASKCTL {
int now_lv; /*现在活动中的LEVEL */
char lv_change; /*在下次任务切换时是否需要改变LEVEL */
struct TASKLEVEL level[MAX_TASKLEVELS];
struct TASK tasks0[MAX_TASKS];
};
extern struct TASKCTL *taskctl;
extern struct TIMER *task_timer;
struct TASK *task_now(void);
struct TASK *task_init(struct MEMMAN *memman);
struct TASK *task_alloc(void);
void task_run(struct TASK *task, int level, int priority);
void task_switch(void);
void task_sleep(struct TASK *task);
/* window.c */
void make_window8(unsigned char *buf, int xsize, int ysize, char *title, char act);
void putfonts8_asc_sht(struct SHEET *sht, int x, int y, int c, int b, char *s, int l);
void make_textbox8(struct SHEET *sht, int x0, int y0, int sx, int sy, int c);
void make_wtitle8(unsigned char *buf, int xsize, char *title, char act);
void change_wtitle8(struct SHEET *sht, char act);
/* console.c */
struct CONSOLE {
struct SHEET *sht;
int cur_x, cur_y, cur_c;
struct TIMER *timer;
};
struct FILEHANDLE {
char *buf;
int size;
int pos;
};
void console_task(struct SHEET *sheet, int memtotal);
void cons_putchar(struct CONSOLE *cons, int chr, char move);
void cons_newline(struct CONSOLE *cons);
void cons_putstr0(struct CONSOLE *cons, char *s);
void cons_putstr1(struct CONSOLE *cons, char *s, int l);
void cons_runcmd(char *cmdline, struct CONSOLE *cons, int *fat, int memtotal);
void cmd_mem(struct CONSOLE *cons, int memtotal);
void cmd_cls(struct CONSOLE *cons);
void cmd_dir(struct CONSOLE *cons);
void cmd_exit(struct CONSOLE *cons, int *fat);
void cmd_start(struct CONSOLE *cons, char *cmdline, int memtotal);
void cmd_ncst(struct CONSOLE *cons, char *cmdline, int memtotal);
void cmd_langmode(struct CONSOLE *cons, char *cmdline);
int cmd_app(struct CONSOLE *cons, int *fat, char *cmdline);
int *hrb_api(int edi, int esi, int ebp, int esp, int ebx, int edx, int ecx, int eax);
int *inthandler0d(int *esp);
int *inthandler0c(int *esp);
void hrb_api_linewin(struct SHEET *sht, int x0, int y0, int x1, int y1, int col);
/* file.c */
struct FILEINFO {
unsigned char name[8], ext[3], type;
char reserve[10];
unsigned short time, date, clustno;
unsigned int size;
};
void file_readfat(int *fat, unsigned char *img);
void file_loadfile(int clustno, int size, char *buf, int *fat, char *img);
struct FILEINFO *file_search(char *name, struct FILEINFO *finfo, int max);
char *file_loadfile2(int clustno, int *psize, int *fat);
/* tek.c */
int tek_getsize(unsigned char *p);
int tek_decomp(unsigned char *p, char *q, int size);
/* bootpack.c */
struct TASK *open_constask(struct SHEET *sht, unsigned int memtotal);
struct SHEET *open_console(struct SHTCTL *shtctl, unsigned int memtotal);