filexorer

/*
    filexorer by xerpi
    compile with:
        gcc -O3 filexorer.c -o filexorer
    usage:
        filexorer <input file 1> <input file 2>

    the output will be <input file 1>.out
    *file 1 and file 2 sizes must be equal*
*/

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

#define BUF_SIZE (4096)

void print_usage();

int main(int argc, char *argv[])
{
    int ret_val = EXIT_SUCCESS;

    if (argc < 3) {
        print_usage();
        ret_val = EXIT_FAILURE;
        goto exit_fail_1;
    }

    FILE *fd_in1, *fd_in2, *fd_out;
    if (!(fd_in1 = fopen(argv[1], "rb"))) {
        printf("Error opening input file 1\n");
        ret_val = EXIT_FAILURE;
        goto exit_fail_1;
    }
    if (!(fd_in2 = fopen(argv[2], "rb"))) {
        printf("Error opening input file 2\n");
        ret_val = EXIT_FAILURE;
        goto exit_fail_2;
    }

    fseek(fd_in1, 0, SEEK_END);
    long int in_size1 = ftell(fd_in1);
    fseek(fd_in1, 0, SEEK_SET);

    fseek(fd_in2, 0, SEEK_END);
    long int in_size2 = ftell(fd_in2);
    fseek(fd_in2, 0, SEEK_SET);

    if (in_size1 != in_size2) {
        printf("ERROR: input files size are different\n");
        ret_val = EXIT_FAILURE;
        goto exit_fail_3;
    }

    char *out_name = malloc(strlen(argv[1]) + strlen(".out") + 1);
    sprintf(out_name, "%s.out", argv[1]);

    if (!(fd_out = fopen(out_name, "wb+"))) {
        printf("Cannot create output file\n");
        ret_val = EXIT_FAILURE;
        goto exit_fail_4;
    }

    unsigned char data_buf1[BUF_SIZE];
    unsigned char data_buf2[BUF_SIZE];

    #define BAR_LEN 50
    long int temp_read = 0;
    long int step_bytes = in_size1/100;
    long int percent = 1;
    size_t bytes_read;
    while ((bytes_read = fread(data_buf1, 1, BUF_SIZE, fd_in1)) &&
                         fread(data_buf2, 1, BUF_SIZE, fd_in2)) {
        size_t i;
        for (i = 0;  i < bytes_read; i++) {
            data_buf1[i] ^= data_buf2[i];
        }
        fwrite(data_buf1, 1, bytes_read, fd_out);

        //Progress bar
        temp_read += bytes_read;
        if (temp_read >= step_bytes) {
            percent++;
            temp_read = 0;
            printf("%3li%% [", percent);
            int j;
            int bar_size = (BAR_LEN*percent)/100;
            for (j = 0; j < BAR_LEN; j++) {
                if (j < bar_size) printf("=");
                else if (j == bar_size) printf(">");
                else printf(" ");
            }
            printf("]\r");
            fflush(stdout);
        }
    }
    fflush(fd_out);
    fclose(fd_out);
    printf("\nFinished!\n");
exit_fail_4:
    free(out_name);
exit_fail_3:
    fclose(fd_in2);
exit_fail_2:
    fclose(fd_in1);
exit_fail_1:
    return ret_val;
}

void print_usage()
{
    printf("filexorer by xerpi\n"
           "usage: filexorer <input file 1> <input file 2>\n"
           "the output will be <input file 1>.out\n"
           "file 1 and file 2 sizes must be equal\n");
}