kernel.c

一个小型的操作系统,采用gcc进行开发,几千行的代码,方便初学者学习

/*
*  Snixos Project version 1.0, 2003.6
*  (C) Copyright 2003,2004,2005 Jockeyson,KeqiangGao <[e-mail]>
*  All Rights Reserved.
*  Distributed under the terms of the GNU General Public License.
*
*  This program is a free and open source software and you can redistribute 
*  it and/or modify it under the terms of the GNU General Public License as
*  published by the Free Software Foundation. As no any liability is assumed 
*  for any incidental or consequential damages in connection with the 
*  information or program fragments contained herein,so any exception arised
*  is at your own risk. It is ABSOLUTELY WITHOUT ANY WARRANTY.
*  Bug report please send to [e-mail] .
*/
/*
  kernel.c: kernel of the Snixos OS project
  Author  : [e-mail]
  Time    : 2003.6
  built   : $Date: 2005/08/02 01:05:56 $
*/

/* 
to append a new task:
call function: 
void newTask(unsigned int taskEntrance, char *taskname);
*/

#include "stdio.h"
#include "string.h"
#include "ctype.h"
#include "mem.h"
#include "fatfs.h"
#include "asm.h"
#include "io.h"
#include "cmostime.h"
#include "keyboard.h"
#include "kernel.h"

/* RCS keyword */
static char rcsDate[] = "Built: $Date: 2005/08/02 01:05:56 $";

#ifdef VIDEO_GRAPH_640X480
const int videoMode = VIDGRAPH_640X480;
#else
const int videoMode = VIDTEXT_80X25;
#endif
#define beepup() asm("pushl $1000\t\n" "call beep\t\n" "add $4,%esp\n")	/* beep for 1sec */

void threadTask();
void cnverTask();
void beep2(int duration, int freq);

typedef struct melody {
    int freq;
    int duration;
} music;



/* kernel start here */
kernelEntrance()
{
    if (videoMode == VIDTEXT_80X25) {
	screen_init();
	ver();
	printf("\ntype help for available commands\n\n%s", PROMPT);
    } else {
	VGAScrInit();
    }

    initInterrupts();
    setPITspeed(1000);		/* PIT interrupt frequency 1000 Hz */
    initMem();			/* init heap memory */
    initFileSystem();		/* RAM disk file system initialization */
    mkDemoFile();		/* create sample files in file system */
    initMC();			/* init myvm virtual machine */
    initTask();			/* init task structure, fill header with dummy data */

    /* 
       create task to be run in system , the threadTask 
       is task running as thread and remember only less 
       than 16 tasks can be created here, and the ktask 
       must be the first to create
     */
    newTask((unsigned) &ktask, "ktask");	/* !! must be the first task to create !! */
    newTask((unsigned) &task1, "task1");
    newTask((unsigned) &task2, "task2");
    newTask((unsigned) &threadTask, "thread1");
    newTask((unsigned) &banner, "banner");
    newTask((unsigned) &timeTask, "timetask");
    newTask((unsigned) &motion, "motion");
    newTask((unsigned) &threadTask, "thread2");
    newTask((unsigned) &cnverTask, "verTask");
    /* task created ok */

    if (videoMode != VIDTEXT_80X25) {
	wrfile("hzk16", (char *) 0x20000, HZK16SIZE);	/* file hzk16 created */
	cnver();
	wrfile("py.mb", (char *) 0x70000, PYMBSIZE);	/* file py.mb created */
    }

    asm("sti");			/* interrupt enabled */
    while (1);			/* waiting for clock interrupt */
}

// typedef unsigned int word;
// typedef unsigned char byte;
// #define outb2(port,data) outb((data),(port))
// extern void delayMS(int i);
// #define delay_msec delayMS
// 
// void sound(const word freq)
// {
//     word freqdiv;
//     byte tmp;
//     freqdiv = 1193180 / freq;
//     outb2(0x43, 0xB6);          /* counter 2 select, binary 16-bit counter,
//                                    first bits 0-7 */
//     printf("H %d L %d\n",(unsigned char) (freqdiv >> 8),(unsigned char) freqdiv);
//     outb2(0x42, (unsigned char) freqdiv);       /* first bits 0-7 */
//     outb2(0x42, (unsigned char) (freqdiv >> 8));        /* then bits 8-15 */
//     tmp = inb(0x61);
//     if (tmp != (tmp | 3))       /* only output if bits are not correctly set */
//         outb2(0x61, tmp | 3);
// }

void play()
{
    int i = 0;
    music music1[] = {
	330, 50,
	392, 50,
	330, 50,
	294, 25,
	330, 25,
	392, 50,
	330, 25,
	294, 25,
	330, 100,
	330, 50,
	392, 50,
	330, 25,
	294, 25,
	262, 50,
	294, 50,
	330, 25,
	392, 25,
	294, 100,
	262, 50,
	262, 25,
	220, 25,
	196, 50,
	196, 25,
	220, 25,
	262, 100,
	294, 100,
	330, 100,
	262, 100,

/*two tiger*/
	262, 25,
	294, 25,
	330, 25,
	262, 25,
	262, 25,
	294, 25,
	330, 25,
	262, 25,
	330, 25,
	349, 25,
	392, 50,
	330, 25,
	349, 25,
	392, 50,
	392, 12,
	440, 12,
	392, 12,
	349, 12,
	330, 25,
	262, 25,
	392, 12,
	440, 12,
	392, 12,
	349, 12,
	330, 25,
	262, 25,
	294, 25,
	196, 25,
	262, 50,
	294, 25,
	196, 25,
	262, 50,
	0, 0,
    };
    while (music1[i].freq > 0) {
	printf("%d %d %d: ", i, music1[i].freq, music1[i].duration);
	beep2(music1[i].duration * 2, music1[i].freq);
	i++;
    }

}

void printHZ(int x, int y, char *s, int mode)
{				/* mode=0 hznm, mode=1 qwm */
    FILE *fp;
    unsigned char buffer[32];
    int i;
    unsigned char qh, wh;
    unsigned long location;

    if ((fp = fopen("hzk16", "r")) == NULL) {
	printf("Can't open hzk16!\n");
	return;
    }
    while (*s) {
	if (0 == mode) {	/* via  hz internal code */
	    qh = *s - 0xa0;
	    wh = *(s + 1) - 0xa0;
	} else {		/* via qw code */
	    qh = *s;
	    wh = *(s + 1);
	}
	location = (94 * (qh - 1) + (wh - 1)) * 32L;
	fseek(fp, location, 0);
	for (i = 0; i < 32; i++) {
	    buffer[i] = fgetc(fp);
	}
	s += 2;			/*get the next HZ */
	putHz(x, y, buffer);	/* write to screen positioned x,y */
	y++;
    }
    fclose(fp);
}

void mkDemoFile()
{
    char tst[] = "  0. What is Snixos Project
	Snixos Project is an experimental operating system designed by
	Jockeyson,
	KeqiangGao < [e-mail]> aiming at multitask / multithread,
	Chinese environment including Chinese characters input and ouput
	etc ...

    Enjoy fun !
	[e-mail], [e-mail]
	Mon Jun 28 11:48:03 CST 2004 "; char tp[] =
#include "sums.vms"
    char *tt =
#include "hanoi.vms"
    wrfile("sums.vms", tp, strlen(tp));
    wrfile("hanoi.vms", tt, strlen(tt));
    wrfile("readme", tst, strlen(tst));
}

/* print 16x16 hz on x,y in 640*480 graph mode , monochrome */
/* x range:0~24,y range:0~39 */
void putHz(int x, int y, char *font)
{
    int i, j, col, seam;
    char *vgamem = (char *) 0xa0000;
    /* x = x % 25; */
    y = y % 40;
    for (i = 0; i < 16; i++) {
	for (col = 0; col < 2; col++) {
	    /* 2 free line for interval between lines */
	    vgamem[(x * (16 + 2)) * 80 + 80 * i + y * 2 + col] =
		font[i * 2 + col];
	}
    }
}

void div0()
{
    asm("movl $1,%eax\n" "movl $0,%ebx\n" "div %bx\n");
}

void ktask()
{
#define MAX_HIST 20
#define HIST_SIZE 30
    extern int textCursorX;
    int kp = 0;
    unsigned int getIdx = 0;
    typedef char cmdHist[HIST_SIZE];
    cmdHist *cmdHistory;
    unsigned int cmdHistIdx = 0;
    long a, temp;
    int i, j, memcnt;
    int cnonoff = 0;
    unsigned short int rt = 0;

    char *rotation[] = {
	"-", "\\", "|", "/"
    };
    /* require memory for command history */
    cmdHistory = (cmdHist *) calloc(1, MAX_HIST * HIST_SIZE);

    while (1) {
#ifndef VIDEO_GRAPH_640X480
	a = temp = tickcount;
	/* display tickcount at top line */
	for (i = 0; i < 8; i++) {
	    a = (a >> (7 - i) * 4) & 0x0000000f;
	    *((char *) (0xb8000 + 144 + i * 2)) = (char) a =
		(a >= 10) ? a + 0x37 : a + 0x30;
	    *((char *) (0xb8000 + 144 + i * 2 + 1)) = 0x29;
	    a = temp;
	}
#else
	VGAPrintStr_8x16(25, 60, rotation[rt = (rt++) % 4], 0);	/* cursor rotation at 25,60 */
#endif
	/* command processing */
	while (!keyEmpty()) {
	    commands cmds;
	    char keyAscii, keyScan;

	    if (getLeftCtrl()) {	/* left ctrl pressed */
		cnonoff++;
		cnonoff = cnonoff & 0x1;
	    }


	    readKeybd(&keyAscii, &keyScan);
	    if (keyAscii != 0x0a) {
		/* backspace, remove tail of keyboard buffer in kernel kb */
		if (keyAscii == '\b') {
		    kp = (kp - 1) % KNLKEYBFLEN;
		    printf("%c", keyAscii);
		    continue;
		}

		switch (keyScan) {	/* RETRIEVE HISTORY BUFFER */
		case UP:
		case LEFT:
		case INSERT:
		    getIdx = (getIdx - 1 + MAX_HIST) % MAX_HIST;
		    goto listHist;
		    break;
		case DOWN:
		case RIGHT:
		case DELETE:
		    getIdx = (getIdx + 1 + MAX_HIST) % MAX_HIST;
		    goto listHist;
		    break;
		case HOME:
		    getIdx = 0;
		    goto listHist;
		    break;
		case END:
		    getIdx = MAX_HIST - 1;
		    goto listHist;
		    break;
		case PAGEUP:
		    getIdx = (getIdx + 5 + MAX_HIST) % MAX_HIST;
		    goto listHist;
		    break;
		case PAGEDOWN:
		    getIdx = (getIdx - 5 + MAX_HIST) % MAX_HIST;
		  listHist:
		    VGAScrGotoxy(textCursorX, 8);
		    printf("                                        ");
		    VGAHideCursor();
		    VGAScrGotoxy(textCursorX, 8);
		    printf("%s", cmdHistory[getIdx]);
		    break;

		default:
		    printf("%c", keyAscii);
		    kb[(kp++) % KNLKEYBFLEN] = keyAscii;
		}
	    } else {		/* keyAscii == 0x0a */
		kb[(kp++) % KNLKEYBFLEN] = '\0';	/* fill EOF to keyboard buffer */
		kp = 0;		/* reset keyboard buffer pointer */

		if (strlen(kb) == 0 && getIdx != cmdHistIdx)
		    strncpy(kb, cmdHistory[getIdx], HIST_SIZE);	/* execute history command just selected */

		getIdx = cmdHistIdx;
		if (strlen(kb) > 1) {
		    strncpy(cmdHistory[(cmdHistIdx) % MAX_HIST], kb,
			    HIST_SIZE);
		    cmdHistIdx = (cmdHistIdx + 1) % MAX_HIST;
		    getIdx = cmdHistIdx;
		}
		printf("\n");

		if(cnonoff){ /* chinese input method enabled */


                }






		cmds = cmdLex(pcmdsRecd);

		switch (cmds) {
		case PS:
		    {
			taskData *p;
			p = task;
			printf
			    ("#\tcs\t\t  ip\t\t  flg\t\t sp\t\t  state\t  ksts\tname\n");
			do {
			    printf
				("%d\t%0x\t%0x\t%0x\t%0x\t%s\t%s\t%s\n",
				 p->pid, p->cs, p->ip, p->flag, p->sp,
				 p->state ? "running" : "suspend",
				 p->ksts ? "RUN" : "SLP", p->taskName);
			    p = p->nextTaskLink;
			}
			while (p != task);
		    }
		    break;
		case VER:
		    ver();
		    break;
		case HELP:
		    {
			int flg = 0;
			ver();
			printf("snixos help routine:\n");
			for (j = 0;
			     j < MAXCMDS && strlen(cmdTabs[j].desc) > 0;
			     j++) {
			    if (strlen(cmdTabs[j].cmdstr) +
				strlen(cmdTabs[j].desc) > 30) {
				printf("\n%-7s: %-30s ", cmdTabs[j].cmdstr,
				       cmdTabs[j].desc);
				flg = 1;
			    } else {
				printf("%s%-7s: %-30s%c",
				       (flg == 1) ? "\n" : "",
				       cmdTabs[j].cmdstr, cmdTabs[j].desc,
				       (j % 2) ? '\n' : ' ');
				flg = 0;
			    }
			}
		    }
		    break;
		case CLEAR:
		    if (videoMode == VIDTEXT_80X25)
			screen_init();
		    else
			VGAScrInit();