text: #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include "mruby.h"
  #include "mruby/compile.h"
  #include "mruby/dump.h"
  #include "mruby/proc.h"
  
  #define RITEBIN_EXT ".mrb"
  #define C_EXT       ".c"
  
  #if defined(__cplusplus)
  extern "C" {
  void mrb_show_version(mrb_state *);
  void mrb_show_copyright(mrb_state *);
  }
  #else
  void mrb_show_version(mrb_state *);
  void mrb_show_copyright(mrb_state *);
  #endif
  
  struct mrbc_args {
    int argc;
    char **argv;
    int idx;
    const char *prog;
    const char *outfile;
    const char *initname;
    mrb_bool check_syntax : 1;
    mrb_bool verbose      : 1;
    mrb_bool debug_info   : 1;
  };
  
  static void
  usage(const char *name)
  {
    static const char *const usage_msg[] = {
    "switches:",
    "-c           check syntax only",
    "-o<outfile>  place the output into <outfile>",
    "-v           print version number, then turn on verbose mode",
    "-g           produce debugging information",
    "-B<symbol>   binary <symbol> output in C language format",
    "--verbose    run at verbose mode",
    "--version    print the version",
    "--copyright  print the copyright",
    NULL
    };
    const char *const *p = usage_msg;
  
    printf("Usage: %s [switches] programfile\n", name);
    while (*p)
      printf("  %s\n", *p++);
  }
  
  static char *
  get_outfilename(mrb_state *mrb, char *infile, const char *ext)
  {
    size_t infilelen;
    size_t extlen;
    char *outfile;
    char *p;
  
    infilelen = strlen(infile);
    extlen = strlen(ext);
    outfile = (char*)mrb_malloc(mrb, infilelen + extlen + 1);
    memcpy(outfile, infile, infilelen + 1);
    if (*ext) {
      if ((p = strrchr(outfile, '.')) == NULL)
        p = outfile + infilelen;
      memcpy(p, ext, extlen + 1);
    }
  
    return outfile;
  }
  
  static int
  parse_args(mrb_state *mrb, int argc, char **argv, struct mrbc_args *args)
  {
    char *outfile = NULL;
    static const struct mrbc_args args_zero = { 0 };
    int i;
  
    *args = args_zero;
    args->argc = argc;
    args->argv = argv;
    args->prog = argv[0];
  
    for (i=1; i<argc; i++) {
      if (argv[i][0] == '-') {
        switch ((argv[i])[1]) {
        case 'o':
          if (args->outfile) {
            fprintf(stderr, "%s: an output file is already specified. (%s)\n",
                    args->prog, outfile);
            return -1;
          }
          if (argv[i][2] == '\0' && argv[i+1]) {
            i++;
            args->outfile = get_outfilename(mrb, argv[i], "");
          }
          else {
            args->outfile = get_outfilename(mrb, argv[i] + 2, "");
          }
          break;
        case 'B':
          if (argv[i][2] == '\0' && argv[i+1]) {
            i++;
            args->initname = argv[i];
          }
          else {
            args->initname = argv[i]+2;
          }
          if (*args->initname == '\0') {
            fprintf(stderr, "%s: function name is not specified.\n", args->prog);
            return -1;
          }
          break;
        case 'c':
          args->check_syntax = TRUE;
          break;
        case 'v':
          if (!args->verbose) mrb_show_version(mrb);
          args->verbose = TRUE;
          break;
        case 'g':
          args->debug_info = TRUE;
          break;
        case 'h':
          return -1;
        case '-':
          if (argv[i][1] == '\n') {
            return i;
          }
          if (strcmp(argv[i] + 2, "version") == 0) {
            mrb_show_version(mrb);
            exit(EXIT_SUCCESS);
          }
          else if (strcmp(argv[i] + 2, "verbose") == 0) {
            args->verbose = TRUE;
            break;
          }
          else if (strcmp(argv[i] + 2, "copyright") == 0) {
            mrb_show_copyright(mrb);
            exit(EXIT_SUCCESS);
          }
          return -1;
        default:
          return i;
        }
      }
      else {
        break;
      }
    }
    return i;
  }
  
  static void
  cleanup(mrb_state *mrb, struct mrbc_args *args)
  {
    if (args->outfile)
      mrb_free(mrb, (void*)args->outfile);
    mrb_close(mrb);
  }
  
  static int
  partial_hook(struct mrb_parser_state *p)
  {
    mrbc_context *c = p->cxt;
    struct mrbc_args *args = (struct mrbc_args *)c->partial_data;
    const char *fn;
  
    if (p->f) fclose(p->f);
    if (args->idx >= args->argc) {
      p->f = NULL;
      return -1;
    }
    fn = args->argv[args->idx++];
    p->f = fopen(fn, "r");
    if (p->f == NULL) {
      fprintf(stderr, "%s: cannot open program file. (%s)\n", args->prog, fn);
      return -1;
    }
    mrb_parser_set_filename(p, fn);
    return 0;
  }
  
  static mrb_value
  load_file(mrb_state *mrb, struct mrbc_args *args)
  {
    mrbc_context *c;
    mrb_value result;
    char *input = args->argv[args->idx];
    FILE *infile;
    mrb_bool need_close = FALSE;
  
    c = mrbc_context_new(mrb);
    if (args->verbose)
      c->dump_result = TRUE;
    c->no_exec = TRUE;
    if (input[0] == '-' && input[1] == '\0') {
      infile = stdin;
    }
    else {
      need_close = TRUE;
      if ((infile = fopen(input, "r")) == NULL) {
        fprintf(stderr, "%s: cannot open program file. (%s)\n", args->prog, input);
        return mrb_nil_value();
      }
    }
    mrbc_filename(mrb, c, input);
    args->idx++;
    if (args->idx < args->argc) {
      need_close = FALSE;
      mrbc_partial_hook(mrb, c, partial_hook, (void*)args);
    }
  
    result = mrb_load_file_cxt(mrb, infile, c);
    if (need_close) fclose(infile);
    mrbc_context_free(mrb, c);
    if (mrb_undef_p(result)) {
      return mrb_nil_value();
    }
    return result;
  }
  
  static int
  dump_file(mrb_state *mrb, FILE *wfp, const char *outfile, struct RProc *proc, struct mrbc_args *args)
  {
    int n = MRB_DUMP_OK;
    mrb_irep *irep = proc->body.irep;
  
    if (args->initname) {
      n = mrb_dump_irep_cfunc(mrb, irep, args->debug_info, wfp, args->initname);
      if (n == MRB_DUMP_INVALID_ARGUMENT) {
        fprintf(stderr, "%s: invalid C language symbol name\n", args->initname);
      }
    }
    else {
      n = mrb_dump_irep_binary(mrb, irep, args->debug_info, wfp);
    }
    if (n != MRB_DUMP_OK) {
      fprintf(stderr, "%s: error in mrb dump (%s) %d\n", args->prog, outfile, n);
    }
    return n;
  }
  
  void
  mrb_init_mrblib(mrb_state *mrb)
  {
  }
  
  #ifndef DISABLE_GEMS
  void
  mrb_init_mrbgems(mrb_state *mrb)
  {
  }
  
  void
  mrb_final_mrbgems(mrb_state *mrb)
  {
  }
  #endif
  