hphp/runtime/vm/type-alias.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-present Facebook, Inc. (http://www.facebook.com)  |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16
  17 #ifndef incl_HPHP_TYPE_ALIAS_H_
  18 #define incl_HPHP_TYPE_ALIAS_H_
  19
  20 #include "hphp/runtime/base/annot-type.h"
  21 #include "hphp/runtime/base/array-data.h"
  22 #include "hphp/runtime/base/attr.h"
  23 #include "hphp/runtime/base/datatype.h"
  24 #include "hphp/runtime/base/type-array.h"
  25 #include "hphp/runtime/base/typed-value.h"
  26 #include "hphp/runtime/base/types.h"
  27 #include "hphp/runtime/base/user-attributes.h"
  28
  29 namespace HPHP {
  30 ///////////////////////////////////////////////////////////////////////////////
  31
  32 struct Class;
  33 struct StringData;
  34 struct ArrayData;
  35
  36 ///////////////////////////////////////////////////////////////////////////////
  37
  38 /*
  39  * This is the runtime representation of a type alias.  Type aliases are only
  40  * allowed when HipHop extensions are enabled.
  41  *
  42  * The `type' field is Object whenever the type alias is basically just a
  43  * name.  At runtime we still might resolve this name to another type alias,
  44  * becoming a type alias for KindOfArray or something in that request.
  45  *
  46  * For the per-request struct, see TypeAliasReq below.
  47  */
  48 struct TypeAlias {
  49   LowStringPtr name;
  50   LowStringPtr value;
  51   Attr attrs;
  52   AnnotType type;
  53   bool nullable;  // null is allowed; for ?Foo aliases
  54   UserAttributeMap userAttrs;
  55   Array typeStructure{Array::Create()};
  56
  57   template<class SerDe>
  58   typename std::enable_if<!SerDe::deserializing>::type
  59   serde(SerDe& sd) {
  60     sd(name)
  61       (value)
  62       (type)
  63       (nullable)
  64       (userAttrs)
  65       (attrs)
  66       ;
  67     TypedValue tv = make_tv<KindOfArray>(typeStructure.get());
  68     sd(tv);
  69   }
  70
  71   template<class SerDe>
  72   typename std::enable_if<SerDe::deserializing>::type
  73   serde(SerDe& sd) {
  74     sd(name)
  75       (value)
  76       (type)
  77       (nullable)
  78       (userAttrs)
  79       (attrs)
  80       ;
  81
  82     TypedValue tv;
  83     sd(tv);
  84     assert(isArrayType(tv.m_type));
  85     typeStructure = tv.m_data.parr;
  86   }
  87
  88 };
  89
  90
  91 ///////////////////////////////////////////////////////////////////////////////
  92
  93 /*
  94  * In a given request, a defined type alias is turned into a TypeAliasReq
  95  * struct.  This contains the information needed to validate parameter type
  96  * hints for a type alias at runtime.
  97  */
  98 struct TypeAliasReq {
  99
 100   /////////////////////////////////////////////////////////////////////////////
 101   // Static constructors.
 102
 103   static TypeAliasReq Invalid();
 104   static TypeAliasReq From(const TypeAlias& alias);
 105   static TypeAliasReq From(TypeAliasReq req, const TypeAlias& alias);
 106
 107
 108   /////////////////////////////////////////////////////////////////////////////
 109   // Comparison.
 110
 111   bool same(const TypeAliasReq& req) const;
 112   bool compat(const TypeAlias& alias) const;
 113
 114
 115   /////////////////////////////////////////////////////////////////////////////
 116   // Data members.
 117
 118   // The aliased type.
 119   AnnotType type{AnnotType::Uninit};
 120   // Overrides `type' if the alias is invalid (e.g., for a nonexistent class).
 121   bool invalid{false};
 122   // For option types, like ?Foo.
 123   bool nullable{false};
 124   // Aliased Class; nullptr if type != Object.
 125   LowPtr<Class> klass{nullptr};
 126   // Needed for error messages; nullptr if not defined.
 127   LowStringPtr name{nullptr};
 128   Array typeStructure{Array::Create()};
 129   UserAttributeMap userAttrs;
 130 };
 131
 132 bool operator==(const TypeAliasReq& l, const TypeAliasReq& r);
 133 bool operator!=(const TypeAliasReq& l, const TypeAliasReq& r);
 134
 135 ///////////////////////////////////////////////////////////////////////////////
 136 }
 137
 138 #define incl_HPHP_TYPE_ALIAS_INL_H_
 139 #include "hphp/runtime/vm/type-alias-inl.h"
 140 #undef incl_HPHP_TYPE_ALIAS_INL_H_
 141
 142 #endif