instruction

ADD 111
SUB 112
MOV 113
XOR 114
CMP 115

parser.c

# include <stdlib.h>
# include <string.h>
# include <stdio.h>
# include <time.h>

struct stud {
	char command[10];
	char var1[50];
	char var2[50];
	int com, first, second;
};

typedef struct stud node;

char *ToUpper( char *str ) {
	char *newstr, *p;
	p = newstr = strdup(str);
	while( *p = toupper(*p) )	p++;
	return newstr;
}

int check_constant( char var[] ) {
	int i = -1;
	while( var[++i] != '\0' ) {
		if( var[i] <= '9' && var[i] >= '0' )	continue;
		else	return 0;
	}
	return 1;
}

node check_reg( node head ) {
	FILE *fp = fopen( "reg", "r" );
	if( fp == NULL )	exit( EXIT_FAILURE );
	int flag1 = 0, flag2 = 0, x;
	char temp_reg[10];
	if( check_constant(head.var1) == 1 ) {
		printf( "error: improper operand type\n" );
		exit( EXIT_FAILURE );
	}
	while( fscanf(fp, "%[^ ] %d", temp_reg, &x) != EOF ) {
		if( temp_reg[0] == '\n' )	memmove( temp_reg, temp_reg + 1, strlen(temp_reg) );
		if( strcasecmp(temp_reg, head.var1) == 0 ) {
			head.first = x;
			flag1 = 1;
		}
		if( strcasecmp(temp_reg, head.var2) == 0 ) {
			head.second = x;
			flag2 = 1;
		}
		if( flag1 == 1 && flag2 == 1 )	break;
	}
	srand (time(NULL));
	if( flag1 == 0 ) {
		head.first = rand() % 9000 + 200;
	}
	if( flag2 == 0 ) {
		head.second = rand() % 18000 + 400;
	}
	if( flag1 && flag2 && head.first == head.second ) {
		printf( "error: different registers expected\n" );
		exit( EXIT_FAILURE );
	}
	fclose(fp);
	return head;
}

node check_command( node head ) {
	FILE *fp = fopen( "instruction", "r" );
	if( fp == NULL )	exit( EXIT_FAILURE );
	char temp_command[10];
	int flag = 0, x;
	while( fscanf(fp, "%[^ ] %d", temp_command, &x) != EOF ) {
		if( temp_command[0] == '\n' )	memmove( temp_command, temp_command + 1, strlen(temp_command) );
		if( strcasecmp(temp_command, head.command) == 0 ) {
			head.com = x;
			flag = 1;
			break;
		}
	}
	if( flag == 0 ) {
		printf("error: command does not exist\n");
		exit( EXIT_FAILURE );
	}
	fclose(fp);
	return head;
}

node read( node head, char *str ) {
	int i = 0;
	while( *str == ' ' )	str++;
	while( *str != ' ' ) {
		head.command[i++] = *str;
		str++;
	}
	head.command[i] = '\0';
	while( *str == ' ' )	str++;
	i = 0;
	while( *str != ' ' && *str != ',' ) {
		head.var1[i++] = *str;
		str++;
	}
	head.var1[i] = '\0';
	while( *str == ' ' )	str++;
	if( *str == ',' )	str++;
	else {
		printf( "error: expected punctuation ','\n" );
		exit( EXIT_FAILURE );
	}
	while( *str == ' ' )	str++;
	i = 0;
	while(*str != ' ' && *str != '\0') {
		head.var2[i++] = *str;
		str++;
	}
	head.var2[i] = '\0';
	return head;
}

int main() {
	node head;
	int reg_res, command_res;
	char *str = (char *) malloc( 100 * sizeof(char) );
	FILE *fp = fopen( "code", "w" );
	if( fp == NULL )	exit( EXIT_FAILURE );
	printf("enter instruction:\n");
	scanf( "%[^\n]s", str );
	head = read( head, str );
	head = check_command( head );
	head = check_reg( head );
	fprintf( fp, "Command: %s %s, %s\nbyte-code: %08x\t%04x %04x\n", ToUpper(head.command), ToUpper(head.var1), ToUpper(head.var2), head.com, head.first, head.second );
	return 0;
}

reg

AH 11
AL 12
AX 13
BH 14
BL 15
BX 16
CH 17
CL 18
CX 19
DH 20
DL 21
DX 22

My Labwork is done :D