boolean
open_a_file (char *name)
{
FILE *the_stream = fopen (name, "a");
if (the_stream != ((FILE *) NULL))
{
add_a_stream (the_stream, my_fclose);
if (the_user == ((char *) NULL))
file_preface = make_file_preface ();
write_line_list (file_preface, the_stream);
return true;
}
return false;
}
/* 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);
}
