mjs-sys 0.1.2

/*
 * Copyright (c) 2017 Cesanta Software Limited
 * All rights reserved
 */

#include "mjs_bcode.h"
#include "mjs_core.h"
#include "mjs_dataview.h"
#include "mjs_exec.h"
#include "mjs_gc.h"
#include "mjs_internal.h"
#include "mjs_json.h"
#include "mjs_object.h"
#include "mjs_primitive.h"
#include "mjs_string.h"
#include "mjs_util.h"

static void mjs_print(struct mjs *mjs) {
  size_t i, num_args = mjs_nargs(mjs);
  for (i = 0; i < num_args; i++) {
    mjs_fprintf(mjs_arg(mjs, i), mjs, stdout);
    putchar(' ');
  }
  putchar('\n');
  mjs_return(mjs, MJS_UNDEFINED);
}

/*
 * If the file with the given filename was already loaded, returns the
 * corresponding bcode part; otherwise returns NULL.
 */
static struct mjs_bcode_part *mjs_get_loaded_file_bcode(struct mjs *mjs,
                                                        const char *filename) {
  int parts_cnt = mjs_bcode_parts_cnt(mjs);
  int i;

  if (filename == NULL) {
    return 0;
  }

  for (i = 0; i < parts_cnt; i++) {
    struct mjs_bcode_part *bp = mjs_bcode_part_get(mjs, i);
    const char *cur_fn = mjs_get_bcode_filename(mjs, bp);
    if (strcmp(filename, cur_fn) == 0) {
      return bp;
    }
  }
  return NULL;
}

static void mjs_load(struct mjs *mjs) {
  mjs_val_t res = MJS_UNDEFINED;
  mjs_val_t arg0 = mjs_arg(mjs, 0);
  mjs_val_t arg1 = mjs_arg(mjs, 1);
  int custom_global = 0; /* whether the custom global object was provided */

  if (mjs_is_string(arg0)) {
    const char *path = mjs_get_cstring(mjs, &arg0);
    struct mjs_bcode_part *bp = NULL;
    mjs_err_t ret;

    if (mjs_is_object(arg1)) {
      custom_global = 1;
      push_mjs_val(&mjs->scopes, arg1);
    }
    bp = mjs_get_loaded_file_bcode(mjs, path);
    if (bp == NULL) {
      /* File was not loaded before, so, load */
      ret = mjs_exec_file(mjs, path, &res);
    } else {
      /*
       * File was already loaded before, so if it was evaluated successfully,
       * then skip the evaluation at all (and assume MJS_OK); otherwise
       * re-evaluate it again.
       *
       * However, if the custom global object was provided, then reevaluate
       * the file in any case.
       */
      if (bp->exec_res != MJS_OK || custom_global) {
        ret = mjs_execute(mjs, bp->start_idx, &res);
      } else {
        ret = MJS_OK;
      }
    }
    if (ret != MJS_OK) {
      /*
       * arg0 and path might be invalidated by executing a file, so refresh
       * them
       */
      arg0 = mjs_arg(mjs, 0);
      path = mjs_get_cstring(mjs, &arg0);
      mjs_prepend_errorf(mjs, ret, "failed to exec file \"%s\"", path);
      goto clean;
    }

  clean:
    if (custom_global) {
      mjs_pop_val(&mjs->scopes);
    }
  }
  mjs_return(mjs, res);
}

static void mjs_get_mjs(struct mjs *mjs) {
  mjs_return(mjs, mjs_mk_foreign(mjs, mjs));
}

static void mjs_chr(struct mjs *mjs) {
  mjs_val_t arg0 = mjs_arg(mjs, 0), res = MJS_NULL;
  int n = mjs_get_int(mjs, arg0);
  if (mjs_is_number(arg0) && n >= 0 && n <= 255) {
    uint8_t s = n;
    res = mjs_mk_string(mjs, (const char *) &s, sizeof(s), 1);
  }
  mjs_return(mjs, res);
}

static void mjs_do_gc(struct mjs *mjs) {
  mjs_val_t arg0 = mjs_arg(mjs, 0);
  mjs_gc(mjs, mjs_is_boolean(arg0) ? mjs_get_bool(mjs, arg0) : 0);
  mjs_return(mjs, arg0);
}

static void mjs_s2o(struct mjs *mjs) {
  mjs_return(mjs,
             mjs_struct_to_obj(mjs, mjs_get_ptr(mjs, mjs_arg(mjs, 0)),
                               (const struct mjs_c_struct_member *) mjs_get_ptr(
                                   mjs, mjs_arg(mjs, 1))));
}

void mjs_init_builtin(struct mjs *mjs, mjs_val_t obj) {
  mjs_val_t v;

  mjs_set(mjs, obj, "global", ~0, obj);

  mjs_set(mjs, obj, "load", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_load));
  mjs_set(mjs, obj, "print", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_print));
  mjs_set(mjs, obj, "ffi", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_ffi_call));
  mjs_set(mjs, obj, "ffi_cb_free", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_ffi_cb_free));
  mjs_set(mjs, obj, "mkstr", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_mkstr));
  mjs_set(mjs, obj, "getMJS", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_get_mjs));
  mjs_set(mjs, obj, "die", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_die));
  mjs_set(mjs, obj, "gc", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_do_gc));
  mjs_set(mjs, obj, "chr", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_chr));
  mjs_set(mjs, obj, "s2o", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_s2o));

  /*
   * Populate JSON.parse() and JSON.stringify()
   */
  v = mjs_mk_object(mjs);
  mjs_set(mjs, v, "stringify", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_op_json_stringify));
  mjs_set(mjs, v, "parse", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_op_json_parse));
  mjs_set(mjs, obj, "JSON", ~0, v);

  /*
   * Populate Object.create()
   */
  v = mjs_mk_object(mjs);
  mjs_set(mjs, v, "create", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_op_create_object));
  mjs_set(mjs, obj, "Object", ~0, v);

  /*
   * Populate numeric stuff
   */
  mjs_set(mjs, obj, "NaN", ~0, MJS_TAG_NAN);
  mjs_set(mjs, obj, "isNaN", ~0,
          mjs_mk_foreign_func(mjs, (mjs_func_ptr_t) mjs_op_isnan));
}