cli.c

#include "cli.h"

#include <ctype.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

// ---------------------------------------------------------------------------
struct option *getopt_get_long_options(getopt_arg_t *opt) {
  size_t count = 0;
  getopt_arg_t null_option = {0};
  do {
    if (!memcmp((void *)&opt[count], (void *)&null_option,
                sizeof(getopt_arg_t))) {
      break;
    } else {
      count++;
    }
  } while (1);

  struct option *gopt = (struct option *)malloc(sizeof(struct option) * count);
  if (!gopt) {
    return NULL;
  }
  for (size_t i = 0; i < count; i++) {
    gopt[i].name = opt[i].name;
    gopt[i].has_arg = opt[i].has_arg;
    gopt[i].flag = opt[i].flag;
    gopt[i].val = opt[i].val;
  }
  return gopt;
}

// ---------------------------------------------------------------------------
void show_usage(char *binary, getopt_arg_t *cli_options) {
  printf("USAGE\n  %s [options] <pdf file> \n\n", binary);
  getopt_arg_t null_option = {0};
  size_t count = 0;
  printf("\nOPTIONS\n");
  do {
    if (!memcmp((void *)&cli_options[count], (void *)&null_option,
                sizeof(getopt_arg_t))) {
      break;
    } else if (cli_options[count].description) {
      printf("  -%c%s%s%s %s%s%s%s\n     ", cli_options[count].val,
             cli_options[count].has_arg != no_argument ? " " : "",
             cli_options[count].has_arg != no_argument
                 ? cli_options[count].arg_name
                 : "",
             cli_options[count].name ? "," : "",
             cli_options[count].name ? "--" : "", cli_options[count].name,
             cli_options[count].has_arg != no_argument ? "=" : "",
             cli_options[count].has_arg != no_argument
                 ? cli_options[count].arg_name
                 : "");
      printf("%s", cli_options[count].description);
      printf("\n\n");
    }
    count++;
  } while (1);
  printf("\n");
  printf("EXAMPLE\n  %s slides.pdf\n\n\n", binary);
  printf("AUTHORS\n  Written by Michael Schwarz.\n\n");
}

// ---------------------------------------------------------------------------
int parse_cli_options(Options *options, getopt_arg_t *cli_options, int argc,
                      char *argv[]) {
  struct option *long_options =
      getopt_get_long_options((getopt_arg_t *)cli_options);
  int c;
  while ((c = getopt_long(argc, argv, ":spo:nhvc:", long_options, NULL)) != EOF) {
    switch (c) {
      case 's':
        options->single = 1;
        break;
      case 'h':
        show_usage(argv[0], cli_options);
        return 1;
      case 'p':
        options->presenter = 1;
        break;
      case 'o':
        options->name = strdup(optarg);
        break;
      case 'n':
        options->nonotes = 1;
        break;
      case 'v':
        printf("pdf-webslides %s\n", APP_VERSION);
        return 1;
      case 'c':
        options->compress = strdup(optarg);
        break;
      case ':':
        printf("Option -%c requires an argument.\n", optopt);
        printf("\n");
        show_usage(argv[0], cli_options);
        return 1;
      case '?':
        if (isprint(optopt)) {
          printf("Unknown option -%c.\n", optopt);
        } else {
          printf("Unknown option character \\x%x.\n", optopt);
        }
        printf("\n");
        show_usage(argv[0], cli_options);
        return 1;
      default:
        show_usage(argv[0], cli_options);
        return 1;
    }
  }

  free(long_options);
  return 0;
}