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/*  
 * Copyright 2012 David Chisnall. All rights reserved. 
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy 
 * of this software and associated documentation files (the "Software"), to 
 * deal in the Software without restriction, including without limitation the 
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or 
 * sell copies of the Software, and to permit persons to whom the Software is 
 * furnished to do so, subject to the following conditions: 
 *  
 * The above copyright notice and this permission notice shall be 
 * included in all copies or substantial portions of the Software. 
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 
 */  
 
#ifndef __CXXABI_H_ 
#define __CXXABI_H_ 
#include <stdint.h> 
#include "unwind.h" 
namespace std  
{ 
	class type_info; 
} 
/* 
 * The cxxabi.h header provides a set of public definitions for types and 
 * functions defined by the Itanium C++ ABI specification.  For reference, see 
 * the ABI specification here: 
 * 
 * http://sourcery.mentor.com/public/cxx-abi/abi.html 
 * 
 * All deviations from this specification, unless otherwise noted, are 
 * accidental. 
 */ 
 
#ifdef __cplusplus 
namespace __cxxabiv1 { 
extern "C" { 
#endif 
/** 
 * Function type to call when an unexpected exception is encountered. 
 */ 
typedef void (*unexpected_handler)(); 
/** 
 * Function type to call when an unrecoverable condition is encountered. 
 */ 
typedef void (*terminate_handler)(); 
 
 
/** 
 * Structure used as a header on thrown exceptions.  This is the same layout as 
 * defined by the Itanium ABI spec, so should be interoperable with any other 
 * implementation of this spec, such as GNU libsupc++. 
 * 
 * This structure is allocated when an exception is thrown.  Unwinding happens 
 * in two phases, the first looks for a handler and the second installs the 
 * context.  This structure stores a cache of the handler location between 
 * phase 1 and phase 2.  Unfortunately, cleanup information is not cached, so 
 * must be looked up in both phases.  This happens for two reasons.  The first 
 * is that we don't know how many frames containing cleanups there will be, and 
 * we should avoid dynamic allocation during unwinding (the exception may be 
 * reporting that we've run out of memory).  The second is that finding 
 * cleanups is much cheaper than finding handlers, because we don't have to 
 * look at the type table at all. 
 * 
 * Note: Several fields of this structure have not-very-informative names. 
 * These are taken from the ABI spec and have not been changed to make it 
 * easier for people referring to to the spec while reading this code. 
 */ 
struct __cxa_exception 
{ 
#if __LP64__ 
	/** 
	 * Reference count.  Used to support the C++11 exception_ptr class.  This 
	 * is prepended to the structure in 64-bit mode and squeezed in to the 
	 * padding left before the 64-bit aligned _Unwind_Exception at the end in 
	 * 32-bit mode. 
	 * 
	 * Note that it is safe to extend this structure at the beginning, rather 
	 * than the end, because the public API for creating it returns the address 
	 * of the end (where the exception object can be stored). 
	 */ 
	uintptr_t referenceCount; 
#endif 
	/** Type info for the thrown object. */ 
	std::type_info *exceptionType; 
	/** Destructor for the object, if one exists. */ 
	void (*exceptionDestructor) (void *);  
	/** Handler called when an exception specification is violated. */ 
	unexpected_handler unexpectedHandler; 
	/** Hander called to terminate. */ 
	terminate_handler terminateHandler; 
	/** 
	 * Next exception in the list.  If an exception is thrown inside a catch 
	 * block and caught in a nested catch, this points to the exception that 
	 * will be handled after the inner catch block completes. 
	 */ 
	__cxa_exception *nextException; 
	/** 
	 * The number of handlers that currently have references to this 
	 * exception.  The top (non-sign) bit of this is used as a flag to indicate 
	 * that the exception is being rethrown, so should not be deleted when its 
	 * handler count reaches 0 (which it doesn't with the top bit set). 
	 */ 
	int handlerCount; 
#if defined(__arm__) && !defined(__ARM_DWARF_EH__) 
	/** 
	 * The ARM EH ABI requires the unwind library to keep track of exceptions 
	 * during cleanups.  These support nesting, so we need to keep a list of 
	 * them. 
	 */ 
	_Unwind_Exception *nextCleanup; 
	/** 
	 * The number of cleanups that are currently being run on this exception.  
	 */ 
	int cleanupCount; 
#endif 
	/** 
	 * The selector value to be returned when installing the catch handler. 
	 * Used at the call site to determine which catch() block should execute. 
	 * This is found in phase 1 of unwinding then installed in phase 2. 
	 */ 
	int handlerSwitchValue; 
	/** 
	 * The action record for the catch.  This is cached during phase 1 
	 * unwinding. 
	 */ 
	const char *actionRecord; 
	/** 
	 * Pointer to the language-specific data area (LSDA) for the handler 
	 * frame.  This is unused in this implementation, but set for ABI 
	 * compatibility in case we want to mix code in very weird ways. 
	 */ 
	const char *languageSpecificData; 
	/** The cached landing pad for the catch handler.*/ 
	void *catchTemp; 
	/** 
	 * The pointer that will be returned as the pointer to the object.  When 
	 * throwing a class and catching a virtual superclass (for example), we 
	 * need to adjust the thrown pointer to make it all work correctly. 
	 */ 
	void *adjustedPtr; 
#if !__LP64__ 
	/** 
	 * Reference count.  Used to support the C++11 exception_ptr class.  This 
	 * is prepended to the structure in 64-bit mode and squeezed in to the 
	 * padding left before the 64-bit aligned _Unwind_Exception at the end in 
	 * 32-bit mode. 
	 * 
	 * Note that it is safe to extend this structure at the beginning, rather 
	 * than the end, because the public API for creating it returns the address 
	 * of the end (where the exception object can be stored)  
	 */ 
	uintptr_t referenceCount; 
#endif 
	/** The language-agnostic part of the exception header. */ 
	_Unwind_Exception unwindHeader; 
}; 
 
/** 
 * ABI-specified globals structure.  Returned by the __cxa_get_globals() 
 * function and its fast variant.  This is a per-thread structure - every 
 * thread will have one lazily allocated. 
 * 
 * This structure is defined by the ABI, so may be used outside of this 
 * library. 
 */ 
struct __cxa_eh_globals 
{ 
	/** 
	 * A linked list of exceptions that are currently caught.  There may be 
	 * several of these in nested catch() blocks. 
	 */ 
	__cxa_exception *caughtExceptions; 
	/** 
	 * The number of uncaught exceptions. 
	 */ 
	unsigned int uncaughtExceptions; 
}; 

#define Y_CXA_EH_GLOBALS_COMPLETE

/** 
 * ABI function returning the __cxa_eh_globals structure. 
 */ 
__cxa_eh_globals *__cxa_get_globals(void); 
/** 
 * Version of __cxa_get_globals() assuming that __cxa_get_globals() has already 
 * been called at least once by this thread. 
 */ 
__cxa_eh_globals *__cxa_get_globals_fast(void); 
 
std::type_info * __cxa_current_exception_type(); 
 
/** 
 * Throws an exception returned by __cxa_current_primary_exception().  This 
 * exception may have been caught in another thread. 
 */ 
void __cxa_rethrow_primary_exception(void* thrown_exception); 
/** 
 * Returns the current exception in a form that can be stored in an 
 * exception_ptr object and then rethrown by a call to 
 * __cxa_rethrow_primary_exception(). 
 */ 
void *__cxa_current_primary_exception(void); 
/** 
 * Increments the reference count of an exception.  Called when an 
 * exception_ptr is copied. 
 */ 
void __cxa_increment_exception_refcount(void* thrown_exception); 
/** 
 * Decrements the reference count of an exception.  Called when an 
 * exception_ptr is deleted. 
 */ 
void __cxa_decrement_exception_refcount(void* thrown_exception); 
/** 
 * Demangles a C++ symbol or type name.  The buffer, if non-NULL, must be 
 * allocated with malloc() and must be *n bytes or more long.  This function 
 * may call realloc() on the value pointed to by buf, and will return the 
 * length of the string via *n. 
 * 
 * The value pointed to by status is set to one of the following: 
 * 
 * 0: success 
 * -1: memory allocation failure 
 * -2: invalid mangled name 
 * -3: invalid arguments 
 */ 
char* __cxa_demangle(const char* mangled_name, 
                     char* buf, 
                     size_t* n, 
                     int* status); 

#ifdef _YNDX_LIBUNWIND_ENABLE_EXCEPTION_BACKTRACE
size_t __cxa_collect_current_exception_backtrace(void** dest, size_t size);
#endif
#ifdef __cplusplus 
} // extern "C" 
} // namespace 
 
namespace abi = __cxxabiv1; 
 
#endif /* __cplusplus */ 
#endif /* __CXXABI_H_ */