cat_s21_cat.c

define _GNU_SOURCE

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <getopt.h>
#include "s21_cat.h"

int main(int argc, char* argv[]) {
    const char* short_opt = "benstvTE";
    const struct option long_opt[] = {
        {"number-nonblank", no_argument, NULL, 'b'},
        {"number", no_argument, NULL, 'n'},
        {"squeeze-blank", no_argument, NULL, 's'},
        {NULL, 0, NULL, 0}
    };
    int index_opt = -1;

    int error = 0;
    struct opts cat_opt = {0, 0, 0, 0, 0, 0};

    for (int opt; (opt = getopt_long(argc, argv, short_opt, long_opt, &index_opt)) != -1;) {
        // printf("opt: %c\n", opt);
        switch (opt) {
            case 'b':
                cat_opt.b = 1;
            break;
            case 'e':
            case 'E':
                cat_opt.e = 1;
                cat_opt.v = 1;
            break;
            case 'n':
                cat_opt.n = 1;
            break;
            case 's':
                cat_opt.s = 1;
            break;
            case 't':
            case 'T':
                cat_opt.t = 1;
                cat_opt.v = 1;
            break;
            case 'v':
                cat_opt.v = 1;
            break;
            case '?':
                fprintf(stderr, "usage: cat [options] [file ...]\n");
                error = 1;
            break;
        }
    }
    if (!error) {
        // printf("-b: %d\n", cat_opt.b);
        // printf("-e: %d\n", cat_opt.e);
        // printf("-n: %d\n", cat_opt.n);
        // printf("-s: %d\n", cat_opt.s);
        // printf("-t: %d\n", cat_opt.t);
        for (int index = optind; index < argc; index++) {
            // printf ("Non-option argument %s\n", argv[index]);
            if (output(argv[index], cat_opt)) {
                fprintf(stderr, "%s: %s: %s\n", CAT, argv[index], strerror(errno));
                error = 1;
            }
        }
    }
    return error;
}

int output(const char* cat_file, struct opts cat_opt) {
    int error = 0;
    int ch;
    FILE* fp;

    fp = fopen(cat_file, "rt");
    if (fp && (ch = getc(fp)) != -1) {
#if defined(__APPLE__)
        size_t num = 1;
#else
        static size_t num = 1;
#endif
        int new_line = 1;
        int exclude_line = 0;
        while (!feof(fp) && !ferror(fp)) {
            if (ch != EOF) {
                if ((cat_opt.b && new_line && ch !='\n') || (cat_opt.n && new_line && !cat_opt.b)) {
                    printf("%*zu\t", WIDTH, num);
                    num++;
                    new_line = 0;
                }
                if (ch == '\n') {
                    new_line = 1;
                    if (cat_opt.e && exclude_line < 2) {
                        printf("$");
                    }
                    if (cat_opt.s) {
                        exclude_line++;
                    }
                } else {
                    exclude_line = 0;
                }
                if (exclude_line > 2) {
                    exclude_line = 0;
                } else {
                    if (cat_opt.v) {
                        if (ch < 9 || (ch > 10 && ch < 32)) {
                            printf("^%c", ch + 64);
                        } else if (cat_opt.t && ch == '\t') {
                            printf("^I");
                        } else if (ch == 127) {
                            printf("^?");
                        } else if (ch > 127 && ch < 160) {
                            printf("M-^%c", ch - 64);
#if defined(__linux__)
                        } else if (ch > 159 && ch < 255) {
                            printf("M-%c", ch - 128);
                        } else if (ch == 255) {
                            printf("M-^?");
#endif
                        } else {
                            putchar(ch);
                        }
                    } else {
                        putchar(ch);
                    }
                }
                ch = getc(fp);
            }
        }
        fclose(fp);
    } else {
        error = 1;
    }
    return error;
}