/*

   +----------------------------------------------------------------------+

   | Zend Engine                                                          |

   +----------------------------------------------------------------------+

   | Copyright © Zend Technologies Ltd., a subsidiary company of          |

   |     Perforce Software, Inc., and Contributors.                       |

   +----------------------------------------------------------------------+

   | This source file is subject to the Modified BSD License that is      |

   | bundled with this package in the file LICENSE, and is available      |

   | through the World Wide Web at <https://www.php.net/license/>.        |

   |                                                                      |

   | SPDX-License-Identifier: BSD-3-Clause                                |

   +----------------------------------------------------------------------+

   | Authors: Ilija Tovilo <ilutov@php.net>                               |

   +----------------------------------------------------------------------+

*/

#include "zend.h"

#include "zend_API.h"

#include "zend_hash.h"

#include "zend_lazy_objects.h"

#include "zend_property_hooks.h"

typedef struct {

  zend_object_iterator it;

  bool by_ref;

  bool declared_props_done;

  zval declared_props;

  bool dynamic_props_done;

  uint32_t dynamic_prop_offset;

  uint32_t dynamic_prop_it;

  zval current_key;

  zval current_data;

} zend_hooked_object_iterator;

static zend_result zho_it_valid(zend_object_iterator *iter);

static void zho_it_move_forward(zend_object_iterator *iter);

static uint32_t zho_find_dynamic_prop_offset(zend_array *properties)

{

  uint32_t offset = 0;

  zval *value;

  ZEND_HASH_MAP_FOREACH_VAL(properties, value) {

    if (Z_TYPE_P(value) != IS_INDIRECT) {

      break;

    }

    offset++;

  } ZEND_HASH_FOREACH_END();

  return offset;

}

static zend_array *zho_build_properties_ex(zend_object *zobj, bool check_access, bool force_ptr, bool include_dynamic_props)

{

  zend_class_entry *ce = zobj->ce;

  zend_array *properties = zend_new_array(include_dynamic_props && zobj->properties

    ? zend_hash_num_elements(zobj->properties)

    : ce->default_properties_count);

  zend_hash_real_init_mixed(properties);

  /* Build list of parents */

  int32_t parent_count = 0;

  for (zend_class_entry *pce = ce; pce; pce = pce->parent) {

    parent_count++;

  }

  zend_class_entry **parents = emalloc(sizeof(zend_class_entry*) * parent_count);

  int32_t i = 0;

  for (zend_class_entry *pce = ce; pce; pce = pce->parent) {

    parents[i++] = pce;

  }

  /* Iterate parents top to bottom */

  i--;

  for (; i >= 0; i--) {

    zend_class_entry *pce = parents[i];

    zend_property_info *prop_info;

    ZEND_HASH_MAP_FOREACH_PTR(&pce->properties_info, prop_info) {

      if (prop_info->flags & ZEND_ACC_STATIC) {

        continue;

      }

      zend_string *property_name = prop_info->name;

      /* When promoting properties from protected to public, use the unmangled name to preserve order. */

      if (prop_info->flags & ZEND_ACC_PROTECTED) {

        const char *tmp = zend_get_unmangled_property_name(property_name);

        zend_string *unmangled_name = zend_string_init(tmp, strlen(tmp), false);

        zend_property_info *child_prop_info = zend_hash_find_ptr(&ce->properties_info, unmangled_name);

        if (child_prop_info && (child_prop_info->flags & ZEND_ACC_PUBLIC)) {

          property_name = unmangled_name;

        } else {

          zend_string_release(unmangled_name);

        }

      }

      if (check_access && zend_check_property_access(zobj, property_name, false) == FAILURE) {

        goto skip_property;

      }

      if (prop_info->hooks || force_ptr) {

        zend_hash_update_ptr(properties, property_name, prop_info);

      } else {

        if (UNEXPECTED(Z_TYPE_P(OBJ_PROP(zobj, prop_info->offset)) == IS_UNDEF)) {

          HT_FLAGS(properties) |= HASH_FLAG_HAS_EMPTY_IND;

        }

        zval *tmp = zend_hash_lookup(properties, property_name);

        ZVAL_INDIRECT(tmp, OBJ_PROP(zobj, prop_info->offset));

      }

skip_property:

      if (property_name != prop_info->name) {

        zend_string_release(property_name);

      }

    } ZEND_HASH_FOREACH_END();

  }

  efree(parents);

  if (include_dynamic_props && zobj->properties) {

    zend_string *prop_name;

    zval *prop_value;

    ZEND_HASH_FOREACH_STR_KEY_VAL(zobj->properties, prop_name, prop_value) {

      if (Z_TYPE_P(prop_value) == IS_INDIRECT) {

        continue;

      }

      zval *tmp = zend_hash_add_new(properties, prop_name, prop_value);

      Z_TRY_ADDREF_P(tmp);

    } ZEND_HASH_FOREACH_END();

  }

  return properties;

}

ZEND_API zend_array *zend_hooked_object_build_properties(zend_object *zobj)

{

  if (UNEXPECTED(zend_lazy_object_must_init(zobj))) {

    zobj = zend_lazy_object_init(zobj);

    if (UNEXPECTED(!zobj)) {

      return (zend_array*) &zend_empty_array;

    }

  }

  return zho_build_properties_ex(zobj, false, false, true);

}

static void zho_dynamic_it_init(zend_hooked_object_iterator *hooked_iter)

{

  zend_object *zobj = Z_OBJ_P(&hooked_iter->it.data);

  zend_array *properties = zobj->handlers->get_properties(zobj);

  hooked_iter->dynamic_props_done = false;

  hooked_iter->dynamic_prop_offset = zho_find_dynamic_prop_offset(properties);

  hooked_iter->dynamic_prop_it = zend_hash_iterator_add(properties, hooked_iter->dynamic_prop_offset);

}

static void zho_it_get_current_key(zend_object_iterator *iter, zval *key);

static void zho_declared_it_fetch_current(zend_object_iterator *iter)

{

  zend_hooked_object_iterator *hooked_iter = (zend_hooked_object_iterator*)iter;

  zend_object *zobj = Z_OBJ_P(&iter->data);

  zend_array *properties = Z_ARR(hooked_iter->declared_props);

  zend_property_info *prop_info = Z_PTR_P(zend_hash_get_current_data(properties));

  if (prop_info->hooks) {

    zend_function *get = prop_info->hooks[ZEND_PROPERTY_HOOK_GET];

    if (!get && (prop_info->flags & ZEND_ACC_VIRTUAL)) {

      return;

    }

    if (hooked_iter->by_ref

     && (get == NULL

      || !(get->common.fn_flags & ZEND_ACC_RETURN_REFERENCE))) {

      zend_throw_error(NULL, "Cannot create reference to property %s::$%s",

        ZSTR_VAL(zobj->ce->name), zend_get_unmangled_property_name(prop_info->name));

      return;

    }

    zend_string *unmangled_name = prop_info->name;

    if (ZSTR_VAL(unmangled_name)[0] == '\0') {

      const char *tmp = zend_get_unmangled_property_name(unmangled_name);

      unmangled_name = zend_string_init(tmp, strlen(tmp), false);

    }

    zval *value = zend_read_property_ex(prop_info->ce, zobj, unmangled_name, /* silent */ true, &hooked_iter->current_data);

    if (unmangled_name != prop_info->name) {

      zend_string_release(unmangled_name);

    }

    if (value == &EG(uninitialized_zval)) {

      return;

    } else if (value != &hooked_iter->current_data) {

      ZVAL_COPY(&hooked_iter->current_data, value);

    }

  } else {

    zval *property = OBJ_PROP(zobj, prop_info->offset);

    ZVAL_DEINDIRECT(property);

    if (Z_TYPE_P(property) == IS_UNDEF) {

      return;

    }

    if (!hooked_iter->by_ref) {

      ZVAL_DEREF(property);

    } else if (Z_TYPE_P(property) != IS_REFERENCE) {

      if (UNEXPECTED(prop_info->flags & ZEND_ACC_READONLY)) {

        zend_throw_error(NULL,

          "Cannot acquire reference to readonly property %s::$%s",

          ZSTR_VAL(prop_info->ce->name), zend_get_unmangled_property_name(prop_info->name));

        return;

      }

      ZVAL_MAKE_REF(property);

      if (ZEND_TYPE_IS_SET(prop_info->type)) {

        ZEND_REF_ADD_TYPE_SOURCE(Z_REF_P(property), prop_info);

      }

    }

    ZVAL_COPY(&hooked_iter->current_data, property);

  }

  if (ZSTR_VAL(prop_info->name)[0] == '\0') {

    const char *tmp = zend_get_unmangled_property_name(prop_info->name);

    ZVAL_STR(&hooked_iter->current_key, zend_string_init(tmp, strlen(tmp), false));

  } else {

    ZVAL_STR_COPY(&hooked_iter->current_key, prop_info->name);

  }

}

static void zho_dynamic_it_fetch_current(zend_object_iterator *iter)

{

  zend_hooked_object_iterator *hooked_iter = (zend_hooked_object_iterator*)iter;

  zend_array *properties = Z_OBJ(iter->data)->properties;

  HashPosition pos = zend_hash_iterator_pos(hooked_iter->dynamic_prop_it, properties);

  if (pos >= properties->nNumUsed) {

    hooked_iter->dynamic_props_done = true;

    return;

  }

  Bucket *bucket = properties->arData + pos;

  if (UNEXPECTED(Z_TYPE(bucket->val) == IS_UNDEF)) {

    return;

  }

  zend_object *zobj = Z_OBJ_P(&hooked_iter->it.data);

  if (bucket->key && zend_check_property_access(zobj, bucket->key, true) != SUCCESS) {

    return;

  }

  if (hooked_iter->by_ref && Z_TYPE(bucket->val) != IS_REFERENCE) {

    ZVAL_MAKE_REF(&bucket->val);

  }

  ZVAL_COPY(&hooked_iter->current_data, &bucket->val);

  if (bucket->key) {

    ZVAL_STR_COPY(&hooked_iter->current_key, bucket->key);

  } else {

    ZVAL_LONG(&hooked_iter->current_key, bucket->h);

  }

}

static void zho_it_fetch_current(zend_object_iterator *iter)

{

  zend_hooked_object_iterator *hooked_iter = (zend_hooked_object_iterator*)iter;

  if (Z_TYPE(hooked_iter->current_data) != IS_UNDEF) {

    return;

  }

  while (true) {

    if (!hooked_iter->declared_props_done) {

      zho_declared_it_fetch_current(iter);

    } else if (!hooked_iter->dynamic_props_done) {

      zho_dynamic_it_fetch_current(iter);

    } else {

      break;

    }

    if (Z_TYPE(hooked_iter->current_data) != IS_UNDEF || EG(exception)) {

      break;

    }

    zho_it_move_forward(iter);

  }

}

static void zho_it_dtor(zend_object_iterator *iter)

{

  zend_hooked_object_iterator *hooked_iter = (zend_hooked_object_iterator*)iter;

  zval_ptr_dtor(&iter->data);

  zval_ptr_dtor(&hooked_iter->declared_props);

  zval_ptr_dtor_nogc(&hooked_iter->current_key);

  zval_ptr_dtor(&hooked_iter->current_data);

  zend_hash_iterator_del(hooked_iter->dynamic_prop_it);

}

static zend_result zho_it_valid(zend_object_iterator *iter)

{

  zend_hooked_object_iterator *hooked_iter = (zend_hooked_object_iterator*)iter;

  zho_it_fetch_current(iter);

  return Z_TYPE(hooked_iter->current_data) != IS_UNDEF ? SUCCESS : FAILURE;

}

static zval *zho_it_get_current_data(zend_object_iterator *iter)

{

  zend_hooked_object_iterator *hooked_iter = (zend_hooked_object_iterator*)iter;

  zho_it_fetch_current(iter);

  return &hooked_iter->current_data;

}

static void zho_it_get_current_key(zend_object_iterator *iter, zval *key)

{

  zend_hooked_object_iterator *hooked_iter = (zend_hooked_object_iterator*)iter;

  zho_it_fetch_current(iter);

  ZVAL_COPY(key, &hooked_iter->current_key);

}

static void zho_it_move_forward(zend_object_iterator *iter)

{

  zend_hooked_object_iterator *hooked_iter = (zend_hooked_object_iterator*)iter;

  zval_ptr_dtor(&hooked_iter->current_data);

  ZVAL_UNDEF(&hooked_iter->current_data);

  zval_ptr_dtor_nogc(&hooked_iter->current_key);

  ZVAL_UNDEF(&hooked_iter->current_key);

  if (!hooked_iter->declared_props_done) {

    zend_array *properties = Z_ARR(hooked_iter->declared_props);

    zend_hash_move_forward(properties);

    if (zend_hash_has_more_elements(properties) != SUCCESS) {

      hooked_iter->declared_props_done = true;

    }

  } else if (!hooked_iter->dynamic_props_done) {

    zend_array *properties = Z_OBJ(iter->data)->properties;

    HashPosition pos = zend_hash_iterator_pos(hooked_iter->dynamic_prop_it, properties);

    pos++;

    EG(ht_iterators)[hooked_iter->dynamic_prop_it].pos = pos;

  }

}

static void zho_it_rewind(zend_object_iterator *iter)

{

  zend_hooked_object_iterator *hooked_iter = (zend_hooked_object_iterator*)iter;

  zval_ptr_dtor(&hooked_iter->current_data);

  ZVAL_UNDEF(&hooked_iter->current_data);

  zval_ptr_dtor_nogc(&hooked_iter->current_key);

  ZVAL_UNDEF(&hooked_iter->current_key);

  zend_array *properties = Z_ARR(hooked_iter->declared_props);

  zend_hash_internal_pointer_reset(properties);

  hooked_iter->declared_props_done = !zend_hash_num_elements(properties);

  hooked_iter->dynamic_props_done = false;

  EG(ht_iterators)[hooked_iter->dynamic_prop_it].pos = hooked_iter->dynamic_prop_offset;

}

static HashTable *zho_it_get_gc(zend_object_iterator *iter, zval **table, int *n)

{

  zend_hooked_object_iterator *hooked_iter = (zend_hooked_object_iterator*)iter;

  zend_get_gc_buffer *gc_buffer = zend_get_gc_buffer_create();

  zend_get_gc_buffer_add_zval(gc_buffer, &iter->data);

  zend_get_gc_buffer_add_zval(gc_buffer, &hooked_iter->declared_props);

  zend_get_gc_buffer_add_zval(gc_buffer, &hooked_iter->current_data);

  zend_get_gc_buffer_use(gc_buffer, table, n);

  return NULL;

}

static const zend_object_iterator_funcs zend_hooked_object_it_funcs = {

  zho_it_dtor,

  zho_it_valid,

  zho_it_get_current_data,

  zho_it_get_current_key,

  zho_it_move_forward,

  zho_it_rewind,

  NULL,

  zho_it_get_gc,

};

ZEND_API zend_object_iterator *zend_hooked_object_get_iterator(zend_class_entry *ce, zval *object, int by_ref)

{

  zend_object *zobj = Z_OBJ_P(object);

  if (UNEXPECTED(zend_lazy_object_must_init(zobj))) {

    zobj = zend_lazy_object_init(zobj);

    if (UNEXPECTED(!zobj)) {

      return NULL;

    }

  }

  zend_hooked_object_iterator *iterator = emalloc(sizeof(zend_hooked_object_iterator));

  zend_iterator_init(&iterator->it);

  ZVAL_OBJ_COPY(&iterator->it.data, zobj);

  iterator->it.funcs = &zend_hooked_object_it_funcs;

  iterator->by_ref = by_ref;

  zend_array *properties = zho_build_properties_ex(zobj, true, true, false);

  ZVAL_ARR(&iterator->declared_props, properties);

  iterator->declared_props_done = !zend_hash_num_elements(properties);

  zho_dynamic_it_init(iterator);

  ZVAL_UNDEF(&iterator->current_key);

  ZVAL_UNDEF(&iterator->current_data);

  return &iterator->it;

}