/*
 * Copyright (c) 1998 Miloslaw Smyk
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Miloslaw Smyk
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * 
 * 18/06/2020  Trev Jackson Added 24bit word support, renamed test.c to d56.c
 *                          Removed make_masks and make_masks2.                  
 *                          Added command line options.
 */

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

#include "5600x_disasm.h"

int main(int argc, char **argv)
{
	struct disasm_data dis, *d = &dis;
	char mem[6];
	unsigned char *memory;
	unsigned char *data;
	FILE *fh, *fh2;
//	fpos_t size;
	int size, advance, c;
    
    unsigned int memory_address_option = 0;
    unsigned int word_length;
    char word_length_string[2] = "32";
    
    char *input_file;
    char *output_file = NULL;
    
    char *usage = "\nDSP56000 disassembler, usage:\n\n    d56 [-w nn] [-m] [-o output-file] source-file\n\nOption Summary\n-w nn            where nn is the length of words in source file, available options are -w 24 or -w 32 (default)\n-m               outputs without memory address for each opcode\n-o output-file   output defaults to stdout, but can be sent to output-file with this option\n\nexample:\n\n    d56 -w 32 -o example.a56 example.bin         disassembles example.bin containing 32bit words, output to example.a56\n\n";

    while((c = getopt(argc, argv, "w:mo:")) != -1) switch (c)
    {
        case 'w':
        {
            strncpy(word_length_string, optarg, 2);
            break;
        }
        case 'm':
            memory_address_option++;
            break;
        case 'o':
            output_file = optarg;
            break;
        case '?':
        default:
            {
                fprintf(stderr,usage);
                exit(1);
            }
    }
    input_file = argv[optind++];
    if(input_file == NULL)
        {
            fprintf(stderr, usage);
            exit(1);
        }
        
    word_length = (((strncmp(word_length_string, "24",2))==0) ? 24 : 32);
    
    if (!(output_file == NULL))
    {
        if(!(fh2 = fopen(output_file, "w"))) output_file = NULL;
    }
    
	if(fh = fopen(input_file, "r"))
	{
		/* get the code's size */

		if(fseek(fh, 0, SEEK_END))
			exit(1);
		else
		{
			size = ftell(fh);
			rewind(fh);
		}

		if(memory = data = malloc(size))
		{
			/* read the entire file into memory */

			if(fread(data, size, 1, fh) == 1)
			{
				/* important part begins here */

				while((memory - data) < size)
				{
					/* The library needs 24-bit words, so we have to throw away
					** upper 8 bits of every instruction's code. Since disassembly
					** processes up to two words per step, we need to prepare
					** two words. */
                    
                    memcpy(mem, memory + (int)((word_length/8)-3), 3);
                    memcpy(mem + 3, memory + (int)((word_length/4)-3), 3);    
                              
					/* tell the library where is the data to disassemble */
					d->memory = mem;

					/* call the line-disassembly routine and note how many
					** words to advance forwards */

					advance = disassemble_opcode(d);

					/* display disassembled line */
                    
                        if(output_file == NULL)
                        { 
                            if (!(memory_address_option)) printf("%04x:\t", ((memory - data) / (word_length/8)));
                            printf("%s\n", d->line_buf);
                        }       
                        else
                        {
                            if (!(memory_address_option)) fprintf(fh2,"%04x:\t", ((memory - data) / (word_length/8)));
                            fprintf(fh2,"%s\n", d->line_buf);
                        }                           
                                        
					/* advance code pointer */
					memory += advance * (word_length/8);
				}
			}

			free(data);
		}
		else
			exit(10);
        
		fclose(fh);
        if (!(output_file == NULL)) fclose(fh2);
	}
}