//bootpack.c 完整代码
#include <stdio.h> void io_hlt(void);
void io_cli(void);
void io_out8(int port, int data);
int io_load_eflags(void);
void io_store_eflags(int eflags); 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 //接受启动信息写成结构体的形式 P89.接着从asmhead.nas中读取启动信息数据（启动地址和内容）
//注意在第一天中，我们已经把asmhead.nas中的信息写到了镜像中。每次系统启动时，首先载入镜像，然后读到asmhead.nas中的内容启动
struct BOOTINFO {
char cyls, leds, vmode, reserve;
short scrnx, scrny;
char *vram;
}; struct SEGMENT_DESCRIPTOR { //GDT的内容；8字节
short limit_low, base_low;
char base_mid, access_right;
char limit_high, base_high;
}; struct GATE_DESCRIPTOR { //IDT的内容，8字节
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);
void load_gdtr(int limit, int addr);
void load_idtr(int limit, int addr); void HariMain(void)
{
struct BOOTINFO *binfo = (struct BOOTINFO *) 0x0ff0;
char s[], mcursor[];
int mx, my; init_gdtidt();
init_palette();
init_screen8(binfo->vram, binfo->scrnx, binfo->scrny); //所谓的使用箭头记号->
mx = (binfo->scrnx - ) / ; /* 启动信息结构体BOOTINFO 从asmhead.nas中读取启动信息数据*/
my = (binfo->scrny - - ) / ; init_mouse_cursor8(mcursor, COL8_008484); //初始化并显示鼠标指针
putblock8_8(binfo->vram, binfo->scrnx, , , mx, my, mcursor, ); sprintf(s, "(%d, %d)", mx, my); //显示变量，先把内容放到字符串s中
putfonts8_asc(binfo->vram, binfo->scrnx, , , COL8_FFFFFF, s); //接着把字符串s显示出来 for (;;) {
io_hlt();
}
} void init_palette(void)
{
static unsigned char table_rgb[ * ] = {
0x00, 0x00, 0x00,
0xff, 0x00, 0x00,
0x00, 0xff, 0x00,
0xff, 0xff, 0x00,
0x00, 0x00, 0xff,
0xff, 0x00, 0xff,
0x00, 0xff, 0xff,
0xff, 0xff, 0xff,
0xc6, 0xc6, 0xc6,
0x84, 0x00, 0x00,
0x00, 0x84, 0x00,
0x84, 0x84, 0x00,
0x00, 0x00, 0x84,
0x84, 0x00, 0x84,
0x00, 0x84, 0x84,
0x84, 0x84, 0x84
};
set_palette(, , table_rgb);
return;
} void set_palette(int start, int end, unsigned char *rgb)
{
int i, eflags;
eflags = io_load_eflags();
io_cli();
io_out8(0x03c8, start);
for (i = start; i <= end; i++) {
io_out8(0x03c9, rgb[] / );
io_out8(0x03c9, rgb[] / );
io_out8(0x03c9, rgb[] / );
rgb += ;
}
io_store_eflags(eflags);
return;
} void boxfill8(unsigned char *vram, int xsize, unsigned char c, int x0, int y0, int x1, int y1)
{
int x, y;
for (y = y0; y <= y1; y++) {
for (x = x0; x <= x1; x++)
vram[y * xsize + x] = c;
}
return;
} void init_screen8(char *vram, int x, int y)
{
boxfill8(vram, x, COL8_008484, , , x - , y - );
boxfill8(vram, x, COL8_C6C6C6, , y - , x - , y - );
boxfill8(vram, x, COL8_FFFFFF, , y - , x - , y - );
boxfill8(vram, x, COL8_C6C6C6, , y - , x - , y - ); boxfill8(vram, x, COL8_FFFFFF, , y - , , y - );
boxfill8(vram, x, COL8_FFFFFF, , y - , , y - );
boxfill8(vram, x, COL8_848484, , y - , , y - );
boxfill8(vram, x, COL8_848484, , y - , , y - );
boxfill8(vram, x, COL8_000000, , y - , , y - );
boxfill8(vram, x, COL8_000000, , y - , , y - ); boxfill8(vram, x, COL8_848484, x - , y - , x - , y - );
boxfill8(vram, x, COL8_848484, x - , y - , x - , y - );
boxfill8(vram, x, COL8_FFFFFF, x - , y - , x - , y - );
boxfill8(vram, x, COL8_FFFFFF, x - , y - , x - , y - );
return;
} //输出，显示字符
void putfont8(char *vram, int xsize, int x, int y, char c, char *font)
{
int i;
char *p, d /* data */;
for (i = ; i < ; i++) {
p = vram + (y + i) * xsize + x;
d = font[i];
if ((d & 0x80) != ) { p[] = c; }
if ((d & 0x40) != ) { p[] = c; }
if ((d & 0x20) != ) { p[] = c; }
if ((d & 0x10) != ) { p[] = c; }
if ((d & 0x08) != ) { p[] = c; }
if ((d & 0x04) != ) { p[] = c; }
if ((d & 0x02) != ) { p[] = c; }
if ((d & 0x01) != ) { p[] = c; }
}
return;
} //输出，显示字符串
void putfonts8_asc(char *vram, int xsize, int x, int y, char c, unsigned char *s)
{
extern char hankaku[];
for (; *s != 0x00; s++) {
putfont8(vram, xsize, x, y, c, hankaku + *s * );
x += ;
}
return;
} void init_mouse_cursor8(char *mouse, char bc)
/* 准备，初始化鼠标指针 16*16=512字符（字节）*/
{
static char cursor[][] = {
"**************..",
"*OOOOOOOOOOO*...",
"*OOOOOOOOOO*....",
"*OOOOOOOOO*.....",
"*OOOOOOOO*......",
"*OOOOOOO*.......",
"*OOOOOOO*.......",
"*OOOOOOOO*......",
"*OOOO**OOO*.....",
"*OOO*..*OOO*....",
"*OO*....*OOO*...",
"*O*......*OOO*..",
"**........*OOO*.",
"*..........*OOO*",
"............*OO*",
".............***"
};
int x, y; for (y = ; y < ; y++) {
for (x = ; x < ; x++) {
if (cursor[y][x] == '*') {
mouse[y * + x] = COL8_000000;
}
if (cursor[y][x] == 'O') {
mouse[y * + x] = COL8_FFFFFF;
}
if (cursor[y][x] == '.') {
mouse[y * + x] = bc;
}
}
}
return;
}
//这里显示鼠标指针；
void putblock8_8(char *vram, int vxsize, int pxsize,
int pysize, int px0, int py0, char *buf, int bxsize)
{
int x, y;
for (y = ; y < pysize; y++) {
for (x = ; x < pxsize; x++) {
vram[(py0 + y) * vxsize + (px0 + x)] = buf[y * bxsize + x];
}
}
return;
} void init_gdtidt(void) //GDT和IDT的初始化
{
struct SEGMENT_DESCRIPTOR *gdt = (struct SEGMENT_DESCRIPTOR *) 0x00270000;
struct GATE_DESCRIPTOR *idt = (struct GATE_DESCRIPTOR *) 0x0026f800;
int i; /* GDT初始化 */
for (i = ; i < ; i++) { //i每次加一；但是gdt指向8字节的结构体；结果地址增加了8
set_segmdesc(gdt + i, , , ); //gdt*（地址）每次+8
}
set_segmdesc(gdt + , 0xffffffff, 0x00000000, 0x4092); //段号为1；大小4G 表示CPU管理的全部内存
set_segmdesc(gdt + , 0x0007ffff, 0x00280000, 0x409a); //段号位2； 大小512K 为bootpack.hrb准备
load_gdtr(0xffff, 0x00270000); //GDT 0x270000-0x27ffff 借助汇编语言的力量给寄存器GDTR赋值 /* IDT初始化 */
for (i = ; i < ; i++) { //和上面一样
set_gatedesc(idt + i, , , );
} //IDT 0x26f800-0x26ffff
load_idtr(0x7ff, 0x0026f800); //向寄存器IDTR赋值 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 >> ) & 0xff;
sd->access_right = ar & 0xff;
sd->limit_high = ((limit >> ) & 0x0f) | ((ar >> ) & 0xf0);
sd->base_high = (base >> ) & 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 >> ) & 0xff;
gd->access_right = ar & 0xff;
gd->offset_high = (offset >> ) & 0xffff;
return;
}
bootpack.c 完整代码day_05
harib02a:
P89 这里做的就是数值写入asmhead.nas中，然后取值；
而不是将这些数值直接写入程序bootpack.c中
//bootpack.c节选
void HariMain(void)
{
char *vram;
int xsize, ysize;
short *binfo_scrnx, *binfo_scrny;
int *binfo_vram;
init_palette();
binfo_scrnx = (short *) 0x0ff4;
binfo_scrny = (short *) 0x0ff6;
binfo_vram = (int *) 0x0ff8;
xsize = *binfo_scrnx;
ysize = *binfo_scrny;
vram = (char *) *binfo_vram; init_screen(vram, xsize, ysize);
for (;;) {
io_hlt();
}
}
harib02b:
这次使用的是结构体的方法重新写一遍，实现的内容是一样的
只是实现方法在这里使用了结构体的写法。如下：
//bootpack.c节选
//接受启动信息写成结构体的形式 P89.接着从asmhead.nas中读取启动信息数据（启动地址和内容）
//注意在第一天中，我们已经把asmhead.nas中的信息写到了镜像中。每次系统启动时，首先载入镜像，然后读到asmhead.nas中的内容启动
struct BOOTINFO {
char cyls, leds, vmode, reserve;
short scrnx, scrny;
char *vram;
};
void HariMain(void)
{
char *vram;
int xsize, ysize;
struct BOOTINFO *binfo; init_palette();
binfo = (struct BOOTINFO *) 0x0ff0;
xsize = (*binfo).scrnx;
ysize = (*binfo).scrny;
vram = (*binfo).vram; init_screen(vram, xsize, ysize); for (;;) {
io_hlt();
}
}
harib02c:
这一步在结构体的基础上，引入了箭头记号的C变成的方式
eg::xsize = (*binfo).scrnx 可以写成 xsize = binfo -> scrnx
进一步改进了程序，但实现的内容任然不变
void HariMain(void)
{
struct BOOTINFO *binfo = (struct BOOTINFO *) 0x0ff0; init_palette();
init_screen(binfo->vram, binfo->scrnx, binfo->scrny); for (;;) {
io_hlt();
}
}
harib02d:
P92 显示字符；
原理：字符使用8*16的像素点阵来表示，
1个字符是16个字节
建立了font结构体数组，用来表示像素点阵字符
函数purfont8()用来将像素点阵字符输出
//字符显示函数
void putfont8(char *vram, int xsize, int x, int y, char c, char *font)
{
int i;
char *p, d /* data */;
for (i = ; i < ; i++) {
p = vram + (y + i) * xsize + x;
d = font[i];
if ((d & 0x80) != ) { p[] = c; }
if ((d & 0x40) != ) { p[] = c; }
if ((d & 0x20) != ) { p[] = c; }
if ((d & 0x10) != ) { p[] = c; }
if ((d & 0x08) != ) { p[] = c; }
if ((d & 0x04) != ) { p[] = c; }
if ((d & 0x02) != ) { p[] = c; }
if ((d & 0x01) != ) { p[] = c; }
}
return;
}
harib02e:
P94 增加了字体的显示； 这里使用了OSASK的字体数据；
原理：相应了字体显示的像素点阵存储在hankaku.txt中。
每一个字体字符都有一个编号。直接查找调用即可
方法：用OSASK的专用编译器makefont.exe将hankaku.txt编译成hankaku.bin
再由连接器bin2obj.exer将hankaku.bin加上必须的接口信息和bootpack.obj链接
生成目标文件
//显示ABC 123
void HariMain(void)
{
struct BOOTINFO *binfo = (struct BOOTINFO *) 0x0ff0;
extern char hankaku[]; init_palette();
init_screen(binfo->vram, binfo->scrnx, binfo->scrny);
putfont8(binfo->vram, binfo->scrnx, , , COL8_FFFFFF, hankaku + 'A' * );
putfont8(binfo->vram, binfo->scrnx, , , COL8_FFFFFF, hankaku + 'B' * );
putfont8(binfo->vram, binfo->scrnx, , , COL8_FFFFFF, hankaku + 'C' * );
putfont8(binfo->vram, binfo->scrnx, , , COL8_FFFFFF, hankaku + '' * );
putfont8(binfo->vram, binfo->scrnx, , , COL8_FFFFFF, hankaku + '' * );
putfont8(binfo->vram, binfo->scrnx, , , COL8_FFFFFF, hankaku + '' * );
for (;;) {
io_hlt();
}
}
harib02f:
接着笔者干脆写了一个函数用来专门显示字符串；putfonts8_asc();
//字符串显示函数
void putfonts8_asc(char *vram, int xsize, int x, int y, char c, unsigned char *s)
{
extern char hankaku[];
for (; *s != 0x00; s++) {
putfont8(vram, xsize, x, y, c, hankaku + *s * );
x += ;
}
return;
}
harib02g:
P98 显示变量的值；虽然我们不能用prinft()函数；但是我们可以使用sprintf()函数
sprintf()将输出的内容写在内存中间。这个函数只对内存进行操作，可以应用于所有的操作系统
笔者还附带的介绍了一下sprintf（）的使用方法和格式；
sprintf(s, "scrnx = %d", binfo->scrnx);
putfonts8_asc(binfo->vram, binfo->scrnx, , , COL8_FFFFFF, s);
harib02h:
P100 鼠标指针的显示。大小设定为16*16的字符数组的大小
内存空间：16*16=256字节；程序写在了init_mouse_cursor8中。
显示的原理和上面字符显示的原理一样；将buf中的数据复制到VARM中去就可以了
接下来笔者写了一个显示的函数putblock8_8()；教材100面有函数详细的介绍。
//bootpack.c 节选
void init_mouse_cursor8(char *mouse, char bc)
/* 准备，初始化鼠标指针 16*16=512字符（字节）*/
{
static char cursor[][] = {
"**************..",
"*OOOOOOOOOOO*...",
"*OOOOOOOOOO*....",
"*OOOOOOOOO*.....",
"*OOOOOOOO*......",
"*OOOOOOO*.......",
"*OOOOOOO*.......",
"*OOOOOOOO*......",
"*OOOO**OOO*.....",
"*OOO*..*OOO*....",
"*OO*....*OOO*...",
"*O*......*OOO*..",
"**........*OOO*.",
"*..........*OOO*",
"............*OO*",
".............***"
};
int x, y; for (y = ; y < ; y++) {
for (x = ; x < ; x++) {
if (cursor[y][x] == '*') {
mouse[y * + x] = COL8_000000;
}
if (cursor[y][x] == 'O') {
mouse[y * + x] = COL8_FFFFFF;
}
if (cursor[y][x] == '.') {
mouse[y * + x] = bc;
}
}
}
return;
}
//这里显示鼠标指针；
void putblock8_8(char *vram, int vxsize, int pxsize,
int pysize, int px0, int py0, char *buf, int bxsize)
{
int x, y;
for (y = ; y < pysize; y++) {
for (x = ; x < pxsize; x++) {
vram[(py0 + y) * vxsize + (px0 + x)] = buf[y * bxsize + x];
}
}
return;
}
harib02i:
P101 怎么才能让鼠标动起来？我们先来看看什么事GDT和IDT
这两个东西是CPU有关的设定（大家暂时不用深究什么是设定，先往下看）
接下来要用汇编语言（有回到汇编语言了）来对CPU做一些鼠标的设定
接下来笔者讲了操作系统分段的概念，关于分段、分页。学过操作系统的都应该知道，不再赘述
GDT：全局段号记录表，存放在内存中的。把需要查找的地址和相应的段号对应起来，便于寻址和查找；
寄存器GDTR用来存储该段内存的起始地址和有效的设定个数
IDT：中断记录表；中断号为0-255；每一个中断号对应一个函数调用，
这些函数就是用来处理操作系统中的中断的，中断发生后，调用通过IDT调用相应的中断函数即可
//bootpack.c节选
struct SEGMENT_DESCRIPTOR { //GDT的内容；8字节
short limit_low, base_low;
char base_mid, access_right;
char limit_high, base_high;
}; struct GATE_DESCRIPTOR { //IDT的内容，8字节
short offset_low, selector;
char dw_count, access_right;
short offset_high;
};
...................
void init_gdtidt(void) //GDT和IDT的初始化
{
struct SEGMENT_DESCRIPTOR *gdt = (struct SEGMENT_DESCRIPTOR *) 0x00270000;
struct GATE_DESCRIPTOR *idt = (struct GATE_DESCRIPTOR *) 0x0026f800;
int i; /* GDT初始化 */
for (i = ; i < ; i++) { //i每次加一；但是gdt指向8字节的结构体；结果地址增加了8
set_segmdesc(gdt + i, , , ); //gdt*（地址）每次+8
}
set_segmdesc(gdt + , 0xffffffff, 0x00000000, 0x4092); //段号为1；大小4G 表示CPU管理的全部内存
set_segmdesc(gdt + , 0x0007ffff, 0x00280000, 0x409a); //段号位2； 大小512K 为bootpack.hrb准备
load_gdtr(0xffff, 0x00270000); //GDT 0x270000-0x27ffff 借助汇编语言的力量给寄存器GDTR赋值 /* IDT初始化 */
for (i = ; i < ; i++) { //和上面一样
set_gatedesc(idt + i, , , );
} //IDT 0x26f800-0x26ffff
load_idtr(0x7ff, 0x0026f800); //向寄存器IDTR赋值 return;
}