mjs-sys 0.1.2

Rust mJS Bindings
Documentation
/*
 * Copyright (c) 2016 Cesanta Software Limited
 * All rights reserved
 */

#include "mjs_object.h"
#include "mjs_conversion.h"
#include "mjs_core.h"
#include "mjs_internal.h"
#include "mjs_primitive.h"
#include "mjs_string.h"
#include "mjs_util.h"

#include "common/mg_str.h"

MJS_PRIVATE mjs_val_t mjs_object_to_value(struct mjs_object *o) {
  if (o == NULL) {
    return MJS_NULL;
  } else {
    return mjs_legit_pointer_to_value(o) | MJS_TAG_OBJECT;
  }
}

MJS_PRIVATE struct mjs_object *get_object_struct(mjs_val_t v) {
  struct mjs_object *ret = NULL;
  if (mjs_is_null(v)) {
    ret = NULL;
  } else {
    assert(mjs_is_object(v));
    ret = (struct mjs_object *) get_ptr(v);
  }
  return ret;
}

mjs_val_t mjs_mk_object(struct mjs *mjs) {
  struct mjs_object *o = new_object(mjs);
  if (o == NULL) {
    return MJS_NULL;
  }
  (void) mjs;
  o->properties = NULL;
  return mjs_object_to_value(o);
}

int mjs_is_object(mjs_val_t v) {
  return (v & MJS_TAG_MASK) == MJS_TAG_OBJECT ||
         (v & MJS_TAG_MASK) == MJS_TAG_ARRAY;
}

MJS_PRIVATE struct mjs_property *mjs_get_own_property(struct mjs *mjs,
                                                      mjs_val_t obj,
                                                      const char *name,
                                                      size_t len) {
  struct mjs_property *p;
  struct mjs_object *o;

  if (!mjs_is_object(obj)) {
    return NULL;
  }

  o = get_object_struct(obj);

  if (len <= 5) {
    mjs_val_t ss = mjs_mk_string(mjs, name, len, 1);
    for (p = o->properties; p != NULL; p = p->next) {
      if (p->name == ss) return p;
    }
  } else {
    for (p = o->properties; p != NULL; p = p->next) {
      if (mjs_strcmp(mjs, &p->name, name, len) == 0) return p;
    }
    return p;
  }

  return NULL;
}

MJS_PRIVATE struct mjs_property *mjs_get_own_property_v(struct mjs *mjs,
                                                        mjs_val_t obj,
                                                        mjs_val_t key) {
  size_t n;
  char *s = NULL;
  int need_free = 0;
  struct mjs_property *p = NULL;
  mjs_err_t err = mjs_to_string(mjs, &key, &s, &n, &need_free);
  if (err == MJS_OK) {
    p = mjs_get_own_property(mjs, obj, s, n);
  }
  if (need_free) free(s);
  return p;
}

MJS_PRIVATE struct mjs_property *mjs_mk_property(struct mjs *mjs,
                                                 mjs_val_t name,
                                                 mjs_val_t value) {
  struct mjs_property *p = new_property(mjs);
  p->next = NULL;
  p->name = name;
  p->value = value;
  return p;
}

mjs_val_t mjs_get(struct mjs *mjs, mjs_val_t obj, const char *name,
                  size_t name_len) {
  struct mjs_property *p;

  if (name_len == (size_t) ~0) {
    name_len = strlen(name);
  }

  p = mjs_get_own_property(mjs, obj, name, name_len);
  if (p == NULL) {
    return MJS_UNDEFINED;
  } else {
    return p->value;
  }
}

mjs_val_t mjs_get_v(struct mjs *mjs, mjs_val_t obj, mjs_val_t name) {
  size_t n;
  char *s = NULL;
  int need_free = 0;
  mjs_val_t ret = MJS_UNDEFINED;

  mjs_err_t err = mjs_to_string(mjs, &name, &s, &n, &need_free);

  if (err == MJS_OK) {
    /* Successfully converted name value to string: get the property */
    ret = mjs_get(mjs, obj, s, n);
  }

  if (need_free) {
    free(s);
    s = NULL;
  }
  return ret;
}

mjs_val_t mjs_get_v_proto(struct mjs *mjs, mjs_val_t obj, mjs_val_t key) {
  struct mjs_property *p;
  mjs_val_t pn = mjs_mk_string(mjs, MJS_PROTO_PROP_NAME, ~0, 1);
  if ((p = mjs_get_own_property_v(mjs, obj, key)) != NULL) return p->value;
  if ((p = mjs_get_own_property_v(mjs, obj, pn)) == NULL) return MJS_UNDEFINED;
  return mjs_get_v_proto(mjs, p->value, key);
}

mjs_err_t mjs_set(struct mjs *mjs, mjs_val_t obj, const char *name,
                  size_t name_len, mjs_val_t val) {
  return mjs_set_internal(mjs, obj, MJS_UNDEFINED, (char *) name, name_len,
                          val);
}

mjs_err_t mjs_set_v(struct mjs *mjs, mjs_val_t obj, mjs_val_t name,
                    mjs_val_t val) {
  return mjs_set_internal(mjs, obj, name, NULL, 0, val);
}

MJS_PRIVATE mjs_err_t mjs_set_internal(struct mjs *mjs, mjs_val_t obj,
                                       mjs_val_t name_v, char *name,
                                       size_t name_len, mjs_val_t val) {
  mjs_err_t rcode = MJS_OK;

  struct mjs_property *p;

  int need_free = 0;

  if (name == NULL) {
    /* Pointer was not provided, so obtain one from the name_v. */
    rcode = mjs_to_string(mjs, &name_v, &name, &name_len, &need_free);
    if (rcode != MJS_OK) {
      goto clean;
    }
  } else {
    /*
     * Pointer was provided, so we ignore name_v. Here we set it to undefined,
     * and the actual value will be calculated later if needed.
     */
    name_v = MJS_UNDEFINED;
  }

  p = mjs_get_own_property(mjs, obj, name, name_len);

  if (p == NULL) {
    struct mjs_object *o;
    if (!mjs_is_object(obj)) {
      return MJS_REFERENCE_ERROR;
    }

    /*
     * name_v might be not a string here. In this case, we need to create a new
     * `name_v`, which will be a string.
     */
    if (!mjs_is_string(name_v)) {
      name_v = mjs_mk_string(mjs, name, name_len, 1);
    }

    p = mjs_mk_property(mjs, name_v, val);

    o = get_object_struct(obj);
    p->next = o->properties;
    o->properties = p;
  }

  p->value = val;

clean:
  if (need_free) {
    free(name);
    name = NULL;
  }
  return rcode;
}

MJS_PRIVATE void mjs_destroy_property(struct mjs_property **p) {
  *p = NULL;
}

/*
 * See comments in `object_public.h`
 */
int mjs_del(struct mjs *mjs, mjs_val_t obj, const char *name, size_t len) {
  struct mjs_property *prop, *prev;

  if (!mjs_is_object(obj)) {
    return -1;
  }
  if (len == (size_t) ~0) {
    len = strlen(name);
  }
  for (prev = NULL, prop = get_object_struct(obj)->properties; prop != NULL;
       prev = prop, prop = prop->next) {
    size_t n;
    const char *s = mjs_get_string(mjs, &prop->name, &n);
    if (n == len && strncmp(s, name, len) == 0) {
      if (prev) {
        prev->next = prop->next;
      } else {
        get_object_struct(obj)->properties = prop->next;
      }
      mjs_destroy_property(&prop);
      return 0;
    }
  }
  return -1;
}

mjs_val_t mjs_next(struct mjs *mjs, mjs_val_t obj, mjs_val_t *iterator) {
  struct mjs_property *p = NULL;
  mjs_val_t key = MJS_UNDEFINED;

  if (*iterator == MJS_UNDEFINED) {
    struct mjs_object *o = get_object_struct(obj);
    p = o->properties;
  } else {
    p = ((struct mjs_property *) get_ptr(*iterator))->next;
  }

  if (p == NULL) {
    *iterator = MJS_UNDEFINED;
  } else {
    key = p->name;
    *iterator = mjs_mk_foreign(mjs, p);
  }

  return key;
}

MJS_PRIVATE void mjs_op_create_object(struct mjs *mjs) {
  mjs_val_t ret = MJS_UNDEFINED;
  mjs_val_t proto_v = mjs_arg(mjs, 0);

  if (!mjs_check_arg(mjs, 0, "proto", MJS_TYPE_OBJECT_GENERIC, &proto_v)) {
    goto clean;
  }

  ret = mjs_mk_object(mjs);
  mjs_set(mjs, ret, MJS_PROTO_PROP_NAME, ~0, proto_v);

clean:
  mjs_return(mjs, ret);
}

mjs_val_t mjs_struct_to_obj(struct mjs *mjs, const void *base,
                            const struct mjs_c_struct_member *defs) {
  mjs_val_t obj;
  const struct mjs_c_struct_member *def = defs;
  if (base == NULL || def == NULL) return MJS_UNDEFINED;
  obj = mjs_mk_object(mjs);
  /* Pin the object while it is being built */
  mjs_own(mjs, &obj);
  /*
   * Because mjs inserts new properties at the head of the list,
   * start from the end so the constructed object more closely resembles
   * the definition.
   */
  while (def->name != NULL) def++;
  for (def--; def >= defs; def--) {
    mjs_val_t v = MJS_UNDEFINED;
    const char *ptr = (const char *) base + def->offset;
    switch (def->type) {
      case MJS_STRUCT_FIELD_TYPE_STRUCT: {
        const void *sub_base = (const void *) ptr;
        const struct mjs_c_struct_member *sub_def =
            (const struct mjs_c_struct_member *) def->arg;
        v = mjs_struct_to_obj(mjs, sub_base, sub_def);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_STRUCT_PTR: {
        const void **sub_base = (const void **) ptr;
        const struct mjs_c_struct_member *sub_def =
            (const struct mjs_c_struct_member *) def->arg;
        if (*sub_base != NULL) {
          v = mjs_struct_to_obj(mjs, *sub_base, sub_def);
        } else {
          v = MJS_NULL;
        }
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_INT: {
        double value = (double) (*(int *) ptr);
        v = mjs_mk_number(mjs, value);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_BOOL: {
        v = mjs_mk_boolean(mjs, *(bool *) ptr);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_DOUBLE: {
        v = mjs_mk_number(mjs, *(double *) ptr);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_FLOAT: {
        float value = *(float *) ptr;
        v = mjs_mk_number(mjs, value);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_CHAR_PTR: {
        const char *value = *(const char **) ptr;
        v = mjs_mk_string(mjs, value, ~0, 1);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_VOID_PTR: {
        v = mjs_mk_foreign(mjs, *(void **) ptr);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_MG_STR_PTR: {
        const struct mg_str *s = *(const struct mg_str **) ptr;
        if (s != NULL) {
          v = mjs_mk_string(mjs, s->p, s->len, 1);
        } else {
          v = MJS_NULL;
        }
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_MG_STR: {
        const struct mg_str *s = (const struct mg_str *) ptr;
        v = mjs_mk_string(mjs, s->p, s->len, 1);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_DATA: {
        const char *dptr = (const char *) ptr;
        const intptr_t dlen = (intptr_t) def->arg;
        v = mjs_mk_string(mjs, dptr, dlen, 1);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_INT8: {
        double value = (double) (*(int8_t *) ptr);
        v = mjs_mk_number(mjs, value);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_INT16: {
        double value = (double) (*(int16_t *) ptr);
        v = mjs_mk_number(mjs, value);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_UINT8: {
        double value = (double) (*(uint8_t *) ptr);
        v = mjs_mk_number(mjs, value);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_UINT16: {
        double value = (double) (*(uint16_t *) ptr);
        v = mjs_mk_number(mjs, value);
        break;
      }
      case MJS_STRUCT_FIELD_TYPE_CUSTOM: {
        mjs_val_t (*fptr)(struct mjs *, const void *) =
            (mjs_val_t (*) (struct mjs *, const void *)) def->arg;
        v = fptr(mjs, ptr);
      }
      default: { break; }
    }
    mjs_set(mjs, obj, def->name, ~0, v);
  }
  mjs_disown(mjs, &obj);
  return obj;
}