FENIX_coreutils/dirname.c

#define _POSIX_C_SOURCE 200809L

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

int main(int argc, char ** argv) {
  int i, last_slash = -1, length;

  if(argc == 1) {
    printf("/\n");
    return 0;
  }

  if(strcmp(argv[1], "//") == 0) {
    printf("/\n");
    return 0;
  }

  length = strlen(argv[1]);

  if(argv[1][length - 1] == '/') {
    argv[1][length - 1] = '\0';
  }

  for(i = 0; i < length; i++) {
    if(argv[1][i] == '/') {
      last_slash = i;
    }
  }

  if(last_slash == -1) {
    printf(".\n");
    return 0;
  }

  argv[1][last_slash] = '\0';

  if(strcmp(argv[1], "//") == 0 || strcmp(argv[1], "") == 0 ||
     strcmp(argv[1], "/") == 0) {
    printf("/\n");
    return 0;
  }

  for(i = last_slash - 1; argv[1][i] == '/'; i--) {
    argv[1][i] = '\0';
  }

  printf("%s\n", argv[1]);

  return 0;
}