DOS外壳的实现

#include "stdio.h" #include "string.h" char _szTitle[] = " Welcome to WuHuayue DOS System"; char _szDefaultDirPath[10] = "C:\\"; char _szCurrentPath[100] = "C:\\"; char _szAllFile[50] = "*.*"; char _DTA[100]; char _szBuffer[100]; int _restart[2]; void _ShowDirectory() { //get current path char *_p; _p = _szCurrentPath; asm{ mov ah,47h mov dl,0 mov si,_p add si,3 int 21h } //show path strcpy(_szBuffer,_szCurrentPath); strcat(_szBuffer,">"); printf("%s",_szBuffer); } void _initscreen() { asm{ push ds mov ax,0B800H mov ds,ax mov cx,80 * 25 * 2 mov si,0 } _1: asm{ mov BYTE PTR [si],' ' add si,2 LOOP _1 } //set backgound color asm{ mov ax,0B800H mov ds,ax mov cx,80 mov si,1 } _2: asm{ mov BYTE PTR [si],00011100B add si,2 LOOP _2 pop ds } //set cursor position asm{ mov ah,02h mov bh,0 mov dh,0 mov dl,0 int 10h } //show title printf("%s\n",_szTitle); //set default directory path char *_p; _p = _szDefaultDirPath; asm{ mov ah,3BH mov dx,_p int 21h } //show default path strcpy(_szBuffer,_szDefaultDirPath); strcat(_szBuffer,">"); printf("%s",_szBuffer); } void _CLS() { //clear screen asm{ push ds mov ax,0B800H mov ds,ax mov cx,80 * 25 * 2 mov si,0 } _1: asm{ mov BYTE PTR [si],' ' add si,2 LOOP _1 pop ds } //set cursor position asm{ mov ah,02h mov bh,0 mov dh,1 mov dl,0 int 10h } //show directory _ShowDirectory(); } void _CD() { int i = 0; //get command line while(_szBuffer[i] != 0) { i++; } i++; //set directory char *_p; _p = &_szBuffer[i]; int _i; _i = strlen(_p); _szBuffer[i + _i] = 0; asm{ mov ah,3BH mov dx,_p int 21h } //check if success asm{ jc _ERROR } //success,show directory goto _end; _ERROR: printf("Specified path not existed!\n\n"); _end: _ShowDirectory(); } void _MD() { int i = 0; //get command line while(_szBuffer[i] != 0) { i++; } i++; //set directory char *_p; _p = &_szBuffer[i]; i = strlen(_szBuffer); int _i; _i = strlen(_p); _szBuffer[i + _i + 1] = 0; asm{ mov ah,39H mov dx,_p int 21h } //check if success asm{ jc _ERROR } //success,show directory goto _end; _ERROR: printf("Cannot create new directory!\n\n"); _end: _ShowDirectory(); } void _RD() { int i = 0; //get command line while(_szBuffer[i] != 0) { i++; } i++; //set directory char *_p; _p = &_szBuffer[i]; i = strlen(_szBuffer); int _i; _i = strlen(_p); _szBuffer[i + _i + 1] = 0; asm{ mov ah,3AH mov dx,_p int 21h } //check if success asm{ jc _ERROR } //success,show directory goto _end; _ERROR: printf("Cannot delete specified directory!\n\n"); _end: _ShowDirectory(); } void _DEL() { int i = 0; //get command line while(_szBuffer[i] != 0) { i++; } i++; //set directory char *_p; _p = &_szBuffer[i]; i = strlen(_szBuffer); int _i; _i = strlen(_p); _szBuffer[i + _i + 1] = 0; asm{ mov ah,41H mov dx,_p int 21h } //check if success asm{ jc _ERROR } //success,show directory goto _end; _ERROR: printf("Cannot delete specified file!\n\n"); _end: _ShowDirectory(); } void _TIME() { //get time char _hour,_min,_sec; asm{ mov ah,2CH int 21h mov _hour,ch mov _min,cl mov _sec,dl } printf("Local Time is %u:%u:%u\n\n",_hour,_min,_sec); _ShowDirectory(); } void _DATE() { //get time short _year; short _month,_day,_week; asm{ mov ah,2AH int 21h mov _year,cx mov BYTE PTR _month,dh mov BYTE PTR _day,dl mov BYTE PTR _week,al } printf("Local date is %u/%u/%u ",_year,_month,_day); switch(_week) { case 1: printf("Monday\n"); break; case 2: printf("Tuesday\n"); break; case 3: printf("Wednesday\n"); break; case 4: printf("Thursday\n"); break; case 5: printf("Friday\n"); break; case 6: printf("Saturday\n"); break; case 7: printf("Sunday\n"); break; } printf("Change date?"); char _c; scanf("%c",&_c); if(_c == 'y' || _c == 'Y') { printf("Enter year:"); scanf("%u",&_year); printf("Enter month:"); scanf("%u",&_month); printf("Enter day:"); scanf("%u",&_day); if(_year < 1980 || _year > 2099) { printf("Incorrect year!\n"); goto _end; } else if(_month < 1 || _month > 12) { printf("Incorrect month!\n"); goto _end; } else if(_day < 1 || _day > 31) { printf("Incorrect day!\n"); goto _end; } asm{ mov ah,2BH mov cx,_year mov bx,_day mov dl,bl mov bx,_month mov dh,bl int 21h } asm{ cmp al,0FFH je _ERROR jmp _end } _ERROR: printf("Cannot set date!\n\n"); } _end: _ShowDirectory(); } void _VER() { char _c,_c1,_OEM; asm{ mov ah,30H int 21h mov _c,al mov _c1,ah mov _OEM,bh } switch(_c) { case 1: strcpy(_szBuffer,"Version of DOS is v1."); break; case 2: strcpy(_szBuffer,"Version of DOS is v2."); break; case 3: strcpy(_szBuffer,"Version of DOS is v3."); break; case 4: strcpy(_szBuffer,"Version of DOS is v4."); break; case 5: strcpy(_szBuffer,"Version of DOS is v5."); break; case 6: strcpy(_szBuffer,"Version of DOS is v6."); break; case 7: strcpy(_szBuffer,"Version of DOS is v7."); break; case 8: strcpy(_szBuffer,"Version of DOS is v8."); break; case 9: strcpy(_szBuffer,"Version of DOS is v9."); break; case 10: strcpy(_szBuffer,"Version of DOS is v10."); break; case 11: strcpy(_szBuffer,"Version of DOS is v11."); break; } switch(_c1) { case 10: strcat(_szBuffer,"1"); break; case 11: strcat(_szBuffer,"2"); break; case 12: strcat(_szBuffer,"3"); break; case 13: strcat(_szBuffer,"4"); break; case 14: strcat(_szBuffer,"5"); break; case 15: strcat(_szBuffer,"6"); break; case 16: strcat(_szBuffer,"7"); break; case 17: strcat(_szBuffer,"8"); break; case 18: strcat(_szBuffer,"9"); break; case 19: strcat(_szBuffer,"10"); break; case 20: strcat(_szBuffer,"11"); break; } printf("%s\n",_szBuffer); printf("OEM SN is %u\n\n",_OEM); _end: _ShowDirectory(); } void _DIR() { long _lSize; int i; char _temp; char *_p; _lSize = 0; //set DTA address _p = _DTA; asm{ mov ah,1AH mov dx,_p int 21h } _p = _szAllFile; asm{ mov ah,4EH mov dx,_p mov cx,00111111B int 21h jc _ERROR //save ax mov _temp,al } //all size if((_DTA[0x15] & 0x10) == 0) { _lSize += (long)_DTA[0x1A]; } //Found first file,look for next file while(1) { i++; //all size if((_DTA[0x15] & 0x10) == 0) { _lSize += (long)_DTA[0x1A]; } //check if this file is a directory if(_DTA[0x15] & 0x10) { printf("["); } _p = &_DTA[0x1E]; printf("%s",_p); //check if this file is a directory if(_DTA[0x15] & 0x10) { printf("]"); } printf(" "); if(i >= 6) { i = 0; printf("\n"); } asm{ mov ah,4FH mov al,_temp int 21h //finished jc _end } } _ERROR: printf("Cannot scan this directory!\n\n"); _end: printf("\n\n Total size is %uByte(s)",_lSize); printf("\n\n"); _ShowDirectory(); } void _ToRestart() { _restart[0] = 0; _restart[1] = 0xFFFF; asm{ lea bx,_restart jmp DWORD PTR [bx] } } void main() { //clear screen _initscreen(); //read command _InputCommand: for(int _i=0;_i<100;_i++) { _szBuffer[_i] = 0; } for(int j=0;(_szBuffer[j] = getchar()) != '\n';j++); _i = strlen(_szBuffer); _szBuffer[_i - 1] = 0; //analyse command for(int i=0;i<strlen(_szBuffer);i++) { if(_szBuffer[i] == ' ') { _szBu