libcxxrt

typeinfo.h (9185B)

---

 /* 
  * Copyright 2010-2011 PathScale, Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  * 1. Redistributions of source code must retain the above copyright notice,
  *    this list of conditions and the following disclaimer.
  *
  * 2. Redistributions in binary form must reproduce the above copyright notice,
  *    this list of conditions and the following disclaimer in the documentation
  *    and/or other materials provided with the distribution.
  * 
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS
  * IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include <stddef.h>
 #include "abi_namespace.h"
 
 namespace ABI_NAMESPACE
 {
 	struct __class_type_info;
 }
 namespace std
 {
 	/**
 	  * Standard type info class.  The layout of this class is specified by the
 	  * ABI.  The layout of the vtable is not, but is intended to be
 	  * compatible with the GNU ABI.
 	  *
 	  * Unlike the GNU version, the vtable layout is considered semi-private.
 	  */
 	class type_info
 	{
 		public:
 		/**
 		 * Virtual destructor.  This class must have one virtual function to
 		 * ensure that it has a vtable.
 		 */
 		virtual ~type_info();
 		bool operator==(const type_info &) const;
 		bool operator!=(const type_info &) const;
 		bool before(const type_info &) const;
 		const char* name() const;
 		type_info();
 		private:
 		type_info(const type_info& rhs);
 		type_info& operator= (const type_info& rhs);
 		const char *__type_name;
 		/*
 		 * The following functions are in this order to match the
 		 * vtable layout of libsupc++.  This allows libcxxrt to be used
 		 * with libraries that depend on this.
 		 *
 		 * These functions are in the public headers for libstdc++, so
 		 * we have to assume that someone will probably call them and
 		 * expect them to work.  Their names must also match the names used in
 		 * libsupc++, so that code linking against this library can subclass
 		 * type_info and correctly fill in the values in the vtables.
 		 */
 		public:
 		/**
 		 * Returns true if this is some pointer type, false otherwise.
 		 */
 		virtual bool __is_pointer_p() const { return false; }
 		/**
 		 * Returns true if this is some function type, false otherwise.
 		 */
 		virtual bool __is_function_p() const { return false; }
 		/**
 		 * Catch function.  Allows external libraries to implement
 		 * their own basic types.  This is used, for example, in the
 		 * GNUstep Objective-C runtime to allow Objective-C types to be
 		 * caught in G++ catch blocks.
 		 *
 		 * The outer parameter indicates the number of outer pointers
 		 * in the high bits.  The low bit indicates whether the
 		 * pointers are const qualified.
 		 */
 		virtual bool __do_catch(const type_info *thrown_type,
 		                        void **thrown_object,
 		                        unsigned outer) const;
 		/**
 		 * Performs an upcast.  This is used in exception handling to
 		 * cast from subclasses to superclasses.  If the upcast is
 		 * possible, it returns true and adjusts the pointer.  If the
 		 * upcast is not possible, it returns false and does not adjust
 		 * the pointer.
 		 */
 		virtual bool __do_upcast(
 		                const ABI_NAMESPACE::__class_type_info *target,
 		                void **thrown_object) const
 		{
 			return false;
 		}
 	};
 }
 
 
 namespace ABI_NAMESPACE
 {
 	/**
 	 * Primitive type info, for intrinsic types.
 	 */
 	struct __fundamental_type_info : public std::type_info
 	{
 		virtual ~__fundamental_type_info();
 	};
 	/**
 	 * Type info for arrays.  
 	 */
 	struct __array_type_info : public std::type_info
 	{
 		virtual ~__array_type_info();
 	};
 	/**
 	 * Type info for functions.
 	 */
 	struct __function_type_info : public std::type_info
 	{
 		virtual ~__function_type_info();
 		virtual bool __is_function_p() const { return true; }
 	};
 	/**
 	 * Type info for enums.
 	 */
 	struct __enum_type_info : public std::type_info
 	{
 		virtual ~__enum_type_info();
 	};
 
 	/**
 	 * Base class for class type info.  Used only for tentative definitions.
 	 */
 	struct __class_type_info : public std::type_info
 	{
 		virtual ~__class_type_info();
 		/**
 		 * Function implementing dynamic casts.
 		 */
 		virtual void *cast_to(void *obj, const struct __class_type_info *other) const;
 		virtual bool __do_upcast(const __class_type_info *target,
 		                       void **thrown_object) const
 		{
 			return this == target;
 		}
 	};
 
 	/**
 	 * Single-inheritance class type info.  This is used for classes containing
 	 * a single non-virtual base class at offset 0.
 	 */
 	struct __si_class_type_info : public __class_type_info
 	{
 		virtual ~__si_class_type_info();
 		const __class_type_info *__base_type;
 		virtual bool __do_upcast(
 		                const ABI_NAMESPACE::__class_type_info *target,
 		                void **thrown_object) const;
 		virtual void *cast_to(void *obj, const struct __class_type_info *other) const;
 	};
 
 	/**
 	 * Type info for base classes.  Classes with multiple bases store an array
 	 * of these, one for each superclass.
 	 */
 	struct __base_class_type_info
 	{
 		const __class_type_info *__base_type;
 		private:
 			/**
 			 * The high __offset_shift bits of this store the (signed) offset
 			 * of the base class.  The low bits store flags from
 			 * __offset_flags_masks.
 			 */
 			long __offset_flags;
 			/**
 			 * Flags used in the low bits of __offset_flags.
 			 */
 			enum __offset_flags_masks
 			{
 				/** This base class is virtual. */
 				__virtual_mask = 0x1,
 				/** This base class is public. */
 				__public_mask = 0x2,
 				/** The number of bits reserved for flags. */
 				__offset_shift = 8
 			};
 		public:
 			/**
 			 * Returns the offset of the base class.
 			 */
 			long offset() const
 			{
 				return __offset_flags >> __offset_shift;
 			}
 			/**
 			 * Returns the flags.
 			 */
 			long flags() const
 			{
 				return __offset_flags & ((1 << __offset_shift) - 1);
 			}
 			/**
 			 * Returns whether this is a public base class.
 			 */
 			bool isPublic() const { return flags() & __public_mask; }
 			/**
 			 * Returns whether this is a virtual base class.
 			 */
 			bool isVirtual() const { return flags() & __virtual_mask; }
 	};
 
 	/**
 	 * Type info for classes with virtual bases or multiple superclasses.
 	 */
 	struct __vmi_class_type_info : public __class_type_info
 	{
 		virtual ~__vmi_class_type_info();
 		/** Flags describing this class.  Contains values from __flags_masks. */
 		unsigned int __flags;
 		/** The number of base classes. */
 		unsigned int __base_count;
 		/** 
 		 * Array of base classes - this actually has __base_count elements, not
 		 * 1.
 		 */
 		__base_class_type_info __base_info[1];
 
 		/**
 		 * Flags used in the __flags field.
 		 */
 		enum __flags_masks
 		{
 			/** The class has non-diamond repeated inheritance. */
 			__non_diamond_repeat_mask = 0x1,
 			/** The class is diamond shaped. */
 			__diamond_shaped_mask = 0x2
 		};
 		virtual bool __do_upcast(
 		                const ABI_NAMESPACE::__class_type_info *target,
 		                void **thrown_object) const;
 		virtual void *cast_to(void *obj, const struct __class_type_info *other) const;
 	};
 
 	/**
 	 * Base class used for both pointer and pointer-to-member type info.
 	 */
 	struct __pbase_type_info : public std::type_info
 	{
 		virtual ~__pbase_type_info();
 		/**
 		 * Flags.  Values from __masks.
 		 */
 		unsigned int __flags;
 		/**
 		 * The type info for the pointee.
 		 */
 		const std::type_info *__pointee;
 
 		/**
 		 * Masks used for qualifiers on the pointer.
 		 */
 		enum __masks
 		{
 			/** Pointer has const qualifier. */
 			__const_mask = 0x1,
 			/** Pointer has volatile qualifier. */
 			__volatile_mask = 0x2,
 			/** Pointer has restrict qualifier. */
 			__restrict_mask = 0x4,
 			/** Pointer points to an incomplete type. */
 			__incomplete_mask = 0x8,
 			/** Pointer is a pointer to a member of an incomplete class. */
 			__incomplete_class_mask = 0x10
 		};
 		virtual bool __do_catch(const type_info *thrown_type,
 		                        void **thrown_object,
 		                        unsigned outer) const;
 	};
 
 	/**
 	 * Pointer type info.
 	 */
 	struct __pointer_type_info : public __pbase_type_info
 	{
 		virtual ~__pointer_type_info();
 		virtual bool __is_pointer_p() const { return true; }
 	};
 
 	/**
 	 * Pointer to member type info.
 	 */
 	struct __pointer_to_member_type_info : public __pbase_type_info
 	{
 		virtual ~__pointer_to_member_type_info();
 		/**
 		 * Pointer to the class containing this member.
 		 */
 		const __class_type_info *__context;
 	};
 
 }