int insert_symtab(const char *symtab,const char *id){
// if string is not present already then it adds that to symtab and returns Identifier
// if string is a keyword then its respective id is returned
char line[100];
int result=search_symtab(symtab,id);
printf("\nInserting '%s' is symtab\n",id);
if(result==-1){
// the token is an identifier and not available in symtab
sprintf(line,"%s 1",id);
printf("SYMTAB >> '%s'\n",line );
writeline(symtab,line);
return IDNTIFIER;
}
if(result==0){
return getKeywordId(id);
}
}
/* Pass-2 assembly algorithm */
void pass2() {
FILE *intr_file, *listing, *obj_prog, *src_file;
char symval[10]="", obj_code[10]="";
char *objprog_name, text_rec[81]=""; //81bytes is enough to hold a text record.
int txtrec_ctr; //Text record counter
int reswb_f = 0; //RESW or RESB found flag. A special flag used during object program production by pass2 only
SIC_addr hex_addr; //program length is just taken as fixed for now.
SIC_reg index = 0x08; //X = 0000 1000(Just taken)
SIC_src_instr src_line; //Part of intr_line
SIC_int_instr intr_line; //Lines read from intermediate file
SIC_list_instr list_line; //Lines written to listing file
intr_line.instr = &src_line; //Associate src_line to intr_line for use
list_line.instr = &intr_line; //Associate intr_line to list_line for use
strcpy(list_line.obj_code,""); //Clear the objcode[] member
#define hex_addr (hex_addr.val)
//Input source file
if((src_file = fopen(program_info.file_name,"r")) == NULL){
fprintf(stderr,"(%s : %d)\n", __FILE__, __LINE__);
fprintf(stderr,"\nError: Could not open source file\n");
exit(1);
}
if((intr_file = fopen(".intermediate","r")) == NULL){
fprintf(stderr,"(%s : %d)\n", __FILE__, __LINE__);
fprintf(stderr,"\nError: Could not load intermediate file\n");
exit(1);
}
if((listing = fopen(".listing","w")) == NULL){ //Assembly listing file
fprintf(stderr,"(%s : %d)\n", __FILE__, __LINE__);
fprintf(stderr,"Error: Cannot open listing file\n");
exit(1);
}
objprog_name = (char*)calloc(strlen(program_info.file_name),sizeof(char));
strncpy(objprog_name, program_info.file_name, strcspn(program_info.file_name, "."));
strcat(objprog_name,".o");
//Object program file
if((obj_prog = fopen(objprog_name,"w")) == NULL){
fprintf(stderr,"(%s : %d)\n", __FILE__, __LINE__);
fprintf(stderr,"\nError: Could not open object file\n");
exit(1);
}
//reset_flags(); //Reset all flags
//Read first line of intermediate file
read_line_intr(intr_file, &intr_line);
//First startement of the source program
if(strcmp(intr_line.instr->opcode,"START")==0){
write_line_list(listing, &list_line);
//Write object program header record
fprintf(obj_prog, "H^%-6s^%06X^%06X\n", program_info.prog_name, program_info.start_addr, program_info.prog_len);
read_line_intr(intr_file, &intr_line);
}
//Initialize first text record
fprintf(obj_prog,"T^%06X^",intr_line.addr.val);
fflush(obj_prog);
//Scan intermediate file till 'END' statement or End of file(EOF)
while((strcmp(intr_line.instr->opcode,"END")!=0) && !feof(intr_file)){
//If comment line
if(strcmp(intr_line.instr->label,".") == 0){
read_line_intr(intr_file, &intr_line);
continue;
}
//Else parse line....
if(search_optab(intr_line.instr->opcode) == FOUND){ //Opcode found
if(strcmp(intr_line.instr->operand,"-") != 0){//Not an empty label field
if(search_symtab(intr_line.instr->operand) == FOUND){//Symbol found
generate_objcode_addr(intr_line.instr->operand);
}
else if(strstr(intr_line.instr->operand,",X") != (char*)0){ //For indexed addressing, add value of X to address
char temp_sym[10]="";
//uint16_t temp;
SIC_addr temp_addr;
//Extract the symbol(excluding ',X') from the operand field
strncpy(temp_sym,intr_line.instr->operand,strcspn(intr_line.instr->operand,",X"));
if(search_symtab(temp_sym) == NOTFOUND){
fprintf(stderr,"(%s : %d)\n", __FILE__, __LINE__);
fprintf(stderr,"Error: Invalid symbol '%s'\n", temp_sym);
exit(1);
}
generate_objcode_addr(temp_sym); //Address of label at temp_sym(not original operand)
hex_addr += index; //Add hex_addr+index_register. Computed as integers
}
else{ //Invalid symbol
hex_addr = 0;
//@ERR: sym_f = 1; //Invalid symbol flag
}
}//operand "-"
else
hex_addr = 0;
//@strcpy(symval,"0000");
//sscanf("0","%X",&hex_addr);
//Make the complete object code
sprintf(symval,"%04X",hex_addr);
//printf("symval: %s\thex_addr: %d\n",symval,hex_addr);
strcpy(obj_code,get_hexcode(intr_line.instr->opcode)); // 04
//@strcat(obj_code,symval);
strcat(obj_code,symval); //04400C
strcpy(list_line.obj_code, obj_code); //Copy it to list_line struct member for write_line_list() operation.
}//end if opcode found
else if(strcmp(intr_line.instr->opcode,"WORD")==0){
//uint16_t temp;
//sscanf(intr_line.instr->operand,"%X",&temp);
hex_addr = intr_line.addr.val;
sprintf(obj_code,"%06X",hex_addr);
strcpy(list_line.obj_code, obj_code); //Copy it to list_line struct member for write_line_list() operation.
}
else if(strcmp(intr_line.instr->opcode,"BYTE")==0){
char temp[10]=""; //Temp constant value variable
if(intr_line.instr->operand[0] == 'C'){ //Eg: C'EOF'
char *ptr;
ptr = strstr(intr_line.instr->operand,"'") + 1;
if(strcmp(ptr,"EOF'") == 0)
strcpy(temp, "454F46");
//Any other character constants can be added here.....TODO
else{
fprintf(stderr,"(%s : %d)\n", __FILE__, __LINE__);
fprintf(stderr,"Error: Invalid constand type\tAt label: %s\n",intr_line.instr->label);
exit(1);
}
}
else if(intr_line.instr->operand[0] == 'X'){ //Eg: X'F1'
char *ptr;
short int i=0;
ptr = strstr(intr_line.instr->operand,"'") + 1;
while(*ptr != SINGLEQUOTE){
temp[i] = *ptr;
ptr++; i++;
}
temp[i] = '\0';
}
strcpy(symval, temp);
strcpy(obj_code, symval);
strcpy(list_line.obj_code, obj_code); //Copy it to list_line struct member for write_line_list() operation.
}
//For RESW and RESB
else if((strcmp(intr_line.instr->opcode,"RESW")==0) || (strcmp(intr_line.instr->opcode,"RESB")==0)){
strcpy(obj_code,"");
strcpy(list_line.obj_code, ""); //Copy it to list_line struct member for write_line_list() operation.
//@txtrec_end_f = 1;
}
//else neither an opcode nor a directive
//Text record production begins here...
if((txtrec_ctr < MAXTRLEN) && (strcmp(intr_line.instr->opcode,"RESW") && strcmp(intr_line.instr->opcode,"RESB"))){
if(reswb_f){ //if RESW or RESB was last found then new text record should begin
fprintf(obj_prog,"%02X",txtrec_ctr);
fprintf(obj_prog,"%s\n",text_rec);
//Reset text_rec string
strcpy(text_rec,"");
txtrec_ctr = 0x0;
//uint16_t temp;
//sscanf(intr_line.addr,"%X",&temp);
//hex_addr = temp;
fprintf(obj_prog,"T^%06X^",intr_line.addr);
reswb_f = 0;
}
//Add obj_code to current text record.(Be careful from adding a '^' with a NULL obj_code)
if(strcmp(obj_code,"") != 0){
strcat(text_rec,"^");
strcat(text_rec,obj_code);
txtrec_ctr += 0x03; // (+ 03H) default for simple SIC
}
}
else if(!strcmp(intr_line.instr->opcode,"RESW") || !strcmp(intr_line.instr->opcode,"RESB"))
reswb_f = 1; //RESW,RESB was found flag
else{ //no more place in the current text record.Create a new one
//Time to flush the generated text_rec string and prepare for a new text record, if any
//Insert the 'length' and 'object codes' fields of the currently ending text record
fprintf(obj_prog,"%02X",txtrec_ctr);
fprintf(obj_prog,"%s\n",text_rec);
//Reset text_rec string
strcpy(text_rec,"");
txtrec_ctr = 0x0;
//uint16_t temp;
//sscanf(intr_line.addr,"%X",&temp);
hex_addr = intr_line.addr.val;
fprintf(obj_prog,"T^%06X^",hex_addr);
if(strcmp(obj_code,"") != 0){
strcat(text_rec,"^");
strcat(text_rec,obj_code);
txtrec_ctr += 0x03;
}
}
//Write to assembly listing file
write_line_list(listing, &list_line);
//Read next line
read_line_intr(intr_file, &intr_line);
}//while(END)
//Insert the left over text record, if any
if(strcmp(text_rec,"") != 0){
//Insert the 'length' and 'object codes' fields of the currently ending text record
fprintf(obj_prog,"%02X",txtrec_ctr);
fprintf(obj_prog,"%s\n",text_rec);
}
//Write last line to assembly listing file
write_line_list(listing, &list_line);
//Write the END record
fprintf(obj_prog,"E^%06X", program_info.start_addr);
//Close all files
fclose(listing);
fclose(intr_file);
fclose(obj_prog);
}
/* Pass-1 assembly algorithm */
void pass1(FILE *src_file){
FILE *intr_file, *symtab;
SIC_src_instr src_line; //Lines read from source file
SIC_int_instr intr_line; //Lines written to intermediate file
SIC_word bytes,inc,const_len;
SIC_addr locctr;
//Macros for writting structs in shortcut
#define bytes (bytes.val)
#define locctr (locctr.val)
#define inc (inc.val)
#define const_len (const_len.val)
//Symbol table for the current source file.
if((symtab = fopen(".symtab","w")) == NULL){
fprintf(stderr,"\nError: Could not open SYMTAB.\n");
exit(EXIT_FAILURE);
}
//Generating output(intermediate) filename
if((intr_file=fopen(".intermediate","w")) == NULL){
fprintf(stderr,"Error: Could not open intermediate file\n");
exit(1);
}
read_line_src(src_file, &src_line);
strcpy(program_info.prog_name, src_line.label); //Get program name(or procedure name)
intr_line.instr = &src_line; //Partial intermediate line constructed
#define start_addr start_addr.val
/* opcode=="START" */
if(strcmp(src_line.opcode,"START")==0){
uint16_t temp;
sscanf(src_line.operand, "%x", &temp);
program_info.start_addr = temp;
locctr = program_info.start_addr;
intr_line.addr.val = temp;
write_line_intr(intr_file, &intr_line); //Define these two functions
read_line_src(src_file, &src_line); //Second line onwards
}
else locctr = 0;
/* Read rest of the lines */
while(strcmp(src_line.opcode,"END")!=0){
if(strcmp(src_line.label,".") == 0){ //If comment line
read_line_src(src_file, &src_line);
continue;
}
inc = 0; //increment value for locctr
if(strcmp(src_line.label,"-")!=0){//If there is something in the label field
if(search_symtab(src_line.label) == FOUND){ //Symbol already defined
fprintf(stderr,"(%s : %d)\n", __FILE__, __LINE__);
fprintf(stderr,"\nError: Symbol '%s' is already defined.\n",src_line.label);
}
else{ //Insert the (symbol,locctr) pair into the SYMTAB
fprintf(symtab, "%s\t%X\n", src_line.label, locctr);
}//if search_symtab()
fflush(symtab);
}//if label is not empty(Not an error)
//else fprintf(stderr,"\nEmpty label.\n");
/* Search OPTAB for opcode */
if(search_optab(src_line.opcode) == FOUND){//Search OPTAB for opcode
inc += WORDSIZE;
//printf("\nOpcode is valid.\n");
}
/* Check the opcode field with various assembler directives */
else if(strcmp(src_line.opcode,"WORD")==0)
inc = WORDSIZE;
else if(strcmp(src_line.opcode,"RESW")==0)
inc = (WORDSIZE * atoi(src_line.operand));
else if(strcmp(src_line.opcode,"RESB")==0)
inc = atoi(src_line.operand);
else if(strcmp(src_line.opcode,"BYTE")==0){
if(src_line.operand[0] == 'C')//For character constants
const_len = strlen(index(src_line.operand,SINGLEQUOTE)) - 2; //Excluding ' from the string 'EOF'
else if(src_line.operand[0] == 'X')//For hexadecimal constants
const_len = 1;
else{
//@ERR: invalid_const_f = 1; //Invalid constant type flag
fprintf(stderr,"(%s : %d)\n", __FILE__, __LINE__);
fprintf(stderr,"\nError: Invalid constant type '%s'\n", src_line.operand);
}
inc = const_len;
}
else{
//@ERR: invalid_op_f = 1; //Invalid opcode flag
fprintf(stderr,"(%s : %d)\n", __FILE__, __LINE__);
fprintf(stderr,"\nError: Invalid opcode.\tAt label: %s\n",src_line.label);
exit(1);
}//if(search OPTAB)
//printf("-----------------------------------------------\n");
//Only change address member of intr_line. That's why I used the 2nd member as a pointer to src_line.
intr_line.addr.val = locctr;
write_line_intr(intr_file, &intr_line);//Write line to intermediate file
locctr += inc; //Update locctr now
read_line_src(src_file, &src_line); //Read next input line
//reset_flags(); //Reset all flags
}//while()
intr_line.addr.val = locctr;
write_line_intr(intr_file, &intr_line); //Write last line
program_info.prog_len = (locctr - program_info.start_addr) + 1;
//printf("\nLength of program = %d(DEC) or %X(HEX)\n",prog_len,prog_len);
fclose(src_file);
fclose(symtab);
fclose(intr_file);
}
int main(int argc,char *argv[])
{
if(argc!=2)
{
printf("Usage: %s <input file>\n",argv[0]);
exit(1);
}
/* Load Optab */
char ***optab=NULL;
int num_ops;
if( (optab=load_optab("opfile",&num_ops)) == NULL)
{
printf("Optab generation failed\n");
exit(2);
}
/* Now let us load and initialize the symtab */
sym_tab *symtab=NULL;
if( (symtab=init_symtab())==NULL )
{
printf("Failed to initiate symtab\n");
free_optab(optab,num_ops);
exit(3);
}
FILE *inp_file=NULL;
if( (inp_file=fopen(argv[1],"r")) == NULL )
{
printf("Failed to open input file\n");
free_optab(optab,num_ops);
free_symtab(symtab);
exit(4);
}
FILE *out_file=NULL;
char *int_filename=NULL;
if( (int_filename=(char *)malloc(strlen(argv[1])+5)) == NULL )
{
printf("Out of memory\n");
free_optab(optab,num_ops);
free_symtab(symtab);
exit(5);
}
strcpy(int_filename,argv[1]);
strcat(int_filename,"_INT");
FILE *int_file=NULL;
if( (int_file=fopen(int_filename,"w+")) == NULL )
{
printf("Failed to open intermediate file\n");
free_optab(optab,num_ops);
free_symtab(symtab);
free(int_filename);
fclose(inp_file);
exit(6);
}
/* And Here We Go */
long int LOCCTR=0;
long int start_addr;
char *read_line=NULL;
size_t to_read = 0;
ssize_t read_len;
char *work_string=NULL;
char *work_string2=NULL;
char *prog_name=NULL;
char *search_space=NULL;
int start_loop=0;
while( (read_len=getline(&read_line,&to_read,inp_file)) != -1 )
{
if( (search_space=(char *)malloc(read_len+1)) == NULL )
{
printf("Out of memory\n");
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(10);
}
strcpy(search_space,"");
sscanf(read_line,"%s",search_space);
if(((*search_space)=='\0')||((*search_space)==';'))
{
free(search_space);
search_space=NULL;
free(read_line);
read_line=NULL;
continue;
}
free(search_space);
search_space=NULL;
if( (prog_name=malloc(read_len+1)) == NULL )
{
printf("Out of memory\n");
fclose(inp_file);
fclose(int_file);
free(int_filename);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(7);
}
if( (work_string=malloc( (read_len-strlen(prog_name)) +1) ) == NULL)
{
printf("Out of memory\n");
fclose(inp_file);
fclose(int_file);
free(prog_name);
free(int_filename);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(7);
}
sscanf(read_line,"%s%s",prog_name,work_string);
if(!strcmp(work_string,"START"))
{
if( (work_string2=malloc((read_len-strlen(work_string))+1)) == NULL )
{
free(work_string);
free(prog_name);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free_optab(optab,num_ops);
free_symtab(symtab);
printf("Out of memory\n");
exit(8);
}
char *searched=strstr(read_line,work_string);
sscanf(searched+strlen(work_string),"%s",work_string2);
if((*work_string2)=='\0')
{
printf("START directive requires an argument\n");
free(work_string);
free(prog_name);
free(work_string2);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(9);
}
char *waste;
LOCCTR=strtol(work_string2,&waste,16);
if(waste == work_string2)
{
printf("Bad Assembly coding...\n");
printf("No suitable value for operand for START directive\n");
free(work_string);
free(prog_name);
free(work_string2);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(9);
}
start_addr=LOCCTR;
fprintf(int_file,"%lX\t%s\t%s\t%lX\n",LOCCTR,prog_name,work_string,start_addr);
free(work_string2);
free(prog_name);
prog_name=NULL;
free(work_string);
work_string=NULL;
free(read_line);
read_line=NULL;
to_read=0;
while( (read_len=getline(&read_line,&to_read,inp_file)) != -1)
{
if( (search_space=(char *)malloc(read_len+1)) == NULL )
{
printf("Out of memory\n");
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(10);
}
strcpy(search_space,"");
sscanf(read_line,"%s",search_space);
if(((*search_space)=='\0')||((*search_space)==';'))
{
free(search_space);
search_space=NULL;
free(read_line);
read_line=NULL;
continue;
}
free(search_space);
search_space=NULL;
break;
}
start_loop=1;
}
else
{
LOCCTR=start_addr=0;
start_loop=1;
}
if(start_loop)
break;
}
// Check if the loop exited becuase the EOF was reached. If so exit...
if(read_len == -1)
{
if(read_line)
free(read_line);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(0);
}
if( (work_string=malloc(read_len+1)) == NULL )
{
printf("Out of memory\n");
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(11);
}
char *label=NULL;
char *pneumonic=NULL;
char *operand=NULL;
decode(read_line,read_len,&label,&pneumonic,&operand,int_filename,inp_file,int_file,NULL,optab,num_ops,symtab,LOCCTR,NULL);
if(label)
label[strlen(label)-1]='\0';
while(strcmp(pneumonic,"END"))
{
if(label)
fprintf(int_file,"%lX\t%s\t%s\t%s\n",LOCCTR,label,pneumonic,operand);
else
{
if(operand)
fprintf(int_file,"%lX\t%s\t%s\n",LOCCTR,pneumonic,operand);
else
fprintf(int_file,"%lX\t%s\n",LOCCTR,pneumonic);
}
if(label)
{
label[strlen(label)-1]='\0';
if(search_symtab(symtab,label)>0)
{
printf("Duplicate symbol at %lX\n",LOCCTR);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(12);
}
else
{
if(insert_symtab(label,symtab,LOCCTR)!=0)
{
printf("Failed to insert into symtab\n");
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(13);
}
}
}
char *opcode,*waste;
if( (opcode=search_optab(optab,pneumonic,num_ops)) != NULL)
{
LOCCTR+=3;
}
else if(!strcmp(pneumonic,"WORD"))
{
LOCCTR+=3;
}
else if(!strcmp(pneumonic,"RESW"))
{
if(operand == NULL)
{
printf("Bad assembly coding...\n");
printf("No value given for operand near RESW directive at %lX\n",LOCCTR);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(23);
}
else
{
LOCCTR+=(3*strtol(operand,&waste,10));
if(waste == operand)
{
printf("Bad assembly coding...\n");
printf("No suitable value was found for allocating memory for RESW directive at %lX\n",LOCCTR);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(21);
}
}
}
else if(!strcmp(pneumonic,"RESB"))
{
if(operand == NULL)
{
printf("Bad assembly coding...\n");
printf("No value given for operand near RESB directive at %lX\n",LOCCTR);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(23);
}
else
{
LOCCTR+=(strtol(operand,&waste,10));
if(waste == operand)
{
printf("Bad assembly coding...\n");
printf("No suitable value was found for allocating memory for RESB directive at %lX\n",LOCCTR);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(22);
}
}
}
else if(!strcmp(pneumonic,"BYTE"))
{
long int old_locctr=LOCCTR;
if(!operand)
{
printf("Bad assembly coding...\n");
printf("No operand corresponding to BYTE directive at %lX\n",LOCCTR);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(52);
}
if( ((*operand)=='c')|| ((*operand)=='C'))
LOCCTR+=(strlen(operand)-3);
else if( ((*operand)=='x')|| ((*operand)=='X'))
{
LOCCTR+=(strlen(operand)-3)/2;
if( (strlen(operand)-3)%2)
LOCCTR+=1;
}
else
{
printf("Bad assembly coding...\n");
printf("Wrong format for constant\n");
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(14);
}
if( (LOCCTR-old_locctr)>MC_SIZE )
{
printf("Constant value too long...\n");
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(50);
}
if( !( (strlen(operand)>=4)&&(operand[1]=='\'')&&(operand[strlen(operand)-1]=='\'') ) )
{
printf("Format for constant is convoluted at %lX...\n",old_locctr);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(51);
}
}
else
{
printf("Opcode not found at %lX...\n",LOCCTR);
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(15);
}
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
read_line=NULL;
to_read=0;
while( (read_len=getline(&read_line,&to_read,inp_file)) != -1)
{
if( (search_space=(char *)malloc(read_len+1)) == NULL )
{
printf("Out of memory\n");
fclose(inp_file);
fclose(int_file);
free(int_filename);
free(read_line);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(10);
}
strcpy(search_space,"");
sscanf(read_line,"%s",search_space);
if(((*search_space)=='\0')||((*search_space)==';'))
{
free(search_space);
search_space=NULL;
free(read_line);
read_line=NULL;
continue;
}
free(search_space);
search_space=NULL;
break;
}
if(read_len == -1)
{
printf("Bad assembly coding...\n");
printf("End of file was reached before END directive\n");
fclose(int_file);
fclose(inp_file);
free(int_filename);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(16);
}
label=NULL;
pneumonic=NULL;
operand=NULL;
decode(read_line,read_len,&label,&pneumonic,&operand,int_filename,inp_file,int_file,NULL,optab,num_ops,symtab,LOCCTR,NULL);
}
//First Pass finished... Beginning second pass
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
fprintf(int_file,"%lX\t%s",LOCCTR,read_line);
free(read_line);
label=NULL;
operand=NULL;
pneumonic=NULL;
read_line=NULL;
fclose(inp_file);
out_file=fopen("a.out","w+");
if( out_file == NULL)
{
printf("Failed to open output file...\n");
fclose(int_file);
free(int_filename);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(30);
}
//Write out the intermediate file and re-open it for second pass
fclose(int_file);
int_file=fopen(int_filename,"r");
if( int_file == NULL)
{
printf("Failed to open intermediate file...\n");
fclose(out_file);
free(int_filename);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(31);
}
int_file=fopen(int_filename,"r");
if( int_file == NULL)
{
printf("Failed to open intermediate file...\n");
fclose(out_file);
free(int_filename);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(31);
}
char *read_raw_line=NULL;
char string_loc[35];
while( (read_len=getline(&read_raw_line,&to_read,int_file)) != -1)
{
read_raw_line[strlen(read_raw_line)-1]='\0';
fprintf(out_file,"%s",read_raw_line);
read_raw_line[strlen(read_raw_line)]='\n';
memset(mc,0,MC_SIZE);
//We dont have to worry about about newlines spaces etc
sscanf(read_raw_line,"%s",string_loc);
read_line=read_raw_line+strlen(string_loc)+1;
decode(read_line,read_len,&label,&pneumonic,&operand,int_filename,NULL,int_file,out_file,optab,num_ops,symtab,LOCCTR,read_raw_line);
if(!label)
fprintf(out_file,"\t");
if(!operand)
fprintf(out_file,"\t");
char *opcode;
long int add;
if( (opcode=search_optab(optab,pneumonic,num_ops)) != NULL )
{
sprintf(mc,"%s",opcode);
if(operand)
{
if( (add=search_symtab(symtab,operand)) > 0 )
{
sprintf(mc+strlen(mc),"%lX",add);
}
else
{
printf("Operand not available in symbol table\n");
fclose(int_file);
fclose(out_file);
free(int_filename);
free(read_raw_line);
free_optab(optab,num_ops);
free_symtab(symtab);
exit(35);
}
}
}
else if(!strcmp(pneumonic,"BYTE"))
{
convert_const(&operand);
}
read_raw_line[strlen(read_raw_line)-1]='\0';
fprintf(out_file,"\t\t%s\n",mc);
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
label=pneumonic=operand=NULL;
free(read_raw_line);
read_raw_line=NULL;
}
if(label)
free(label);
if(operand)
free(operand);
if(pneumonic)
free(pneumonic);
fclose(int_file);
fclose(out_file);
free(int_filename);
free_optab(optab,num_ops);
free_symtab(symtab);
return 0;
}
