/*

* Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

* e32/compsupp/symaehabi/symbian_support.h

*

*/

#ifndef SYMBIAN_SUPPORT_H

#define SYMBIAN_SUPPORT_H

#include <e32def_private.h>

#ifdef __cplusplus

typedef _Unwind_Control_Block UCB;

using std::terminate_handler;

using std::unexpected_handler;

using std::terminate;

using std::unexpected;

using std::type_info;

/* --------- Exception control object: --------- */

// Type __cxa_exception is the combined C++ housekeeping (LEO) and UCB.

// It will be followed by the user exception object, hence must ensure

// the latter is aligned on an 8 byte boundary.

struct __cxa_exception {

  const type_info *exceptionType;       // RTTI object describing the type of the exception

  void *(*exceptionDestructor)(void *); // Destructor for the exception object (may be NULL)

  unexpected_handler unexpectedHandler; // Handler in force after evaluating throw expr

  terminate_handler terminateHandler;   // Handler in force after evaluating throw expr

  __cxa_exception *nextCaughtException; // Chain of "currently caught" c++ exception objects

  uint32_t handlerCount;                // Count of how many handlers this EO is "caught" in

  __cxa_exception *nextPropagatingException; // Chain of objects saved over cleanup

  uint32_t propagationCount;            // Count of live propagations (throws) of this EO

  UCB ucb;                              // Forces alignment of next item to 8-byte boundary

};

// Exceptions global support

typedef void (*handler)(void);

struct __cxa_eh_globals {

  uint32_t uncaughtExceptions;               // counter

  unexpected_handler unexpectedHandler;      // per-thread handler

  terminate_handler terminateHandler;        // per-thread handler

  bool implementation_ever_called_terminate; // true if it ever did

  handler call_hook;     // transient field to tell terminate/unexpected which hook to call

  __cxa_exception *caughtExceptions;         // chain of "caught" exceptions

  __cxa_exception *propagatingExceptions;    // chain of "propagating" (in cleanup) exceptions

  void *emergency_buffer;                    // emergency buffer for when rest of heap full

};

// emergency storage reserve primarily for throwing OOM exceptions

struct emergency_eco {

  __cxa_exception ep;

    XLeaveException aUserLeaveException;

};

struct emergency_buffer {

  bool inuse;

  struct emergency_eco eco;

};

class TCppRTExceptionsGlobals

	{

public:

	IMPORT_C TCppRTExceptionsGlobals();

private:

	__cxa_eh_globals thread_globals;

	emergency_buffer buffer;

	};

#endif

// Support for finding ROM resident ExIdx tables

#define GET_ROM_EST(u) ((TRomExceptionSearchTable *)((u)->unwinder_cache.reserved4))

#define SET_ROM_EST(u,e) ((TRomExceptionSearchTable *)((u)->unwinder_cache.reserved4=(uint32_t)e))

#define GET_EXCEPTION_DESCRIPTOR(u) ((TExceptionDescriptor *)((u)->unwinder_cache.reserved5))

#define SET_EXCEPTION_DESCRIPTOR(u,e) ((TExceptionDescriptor *)((u)->unwinder_cache.reserved5=(uint32_t)e))

// Support for checking which version of EHABI is in play

#define EHABI_MASK 0xfffffffc

// Checks if image implements V2 of EHABI

#define EHABI_V2(u) ((GET_EXCEPTION_DESCRIPTOR(u)->iROSegmentBase) & 1)

#define GET_RO_BASE(u) (((u)->iROSegmentBase) & EHABI_MASK)

#define ADDRESS_IN_EXCEPTION_DESCRIPTOR_RANGE(addr, aEDp) (((addr) >= GET_RO_BASE(aEDp)) && ((addr) < (aEDp)->iROSegmentLimit))

#define GET_EST_FENCEPOST(aESTp) ((aESTp)->iEntries[(aESTp)->iNumEntries])

#define ADDRESS_IN_ROM_EST(addr, aESTp) (((addr) >= (aESTp)->iEntries[0]) && ((addr) < GET_EST_FENCEPOST((aESTp))))

// Non __EPOC32__ versions defined in unwinder.c

#define EIT_base(u) \

    ((const __EIT_entry *)((GET_EXCEPTION_DESCRIPTOR(u))->iExIdxBase))

#define EIT_limit(u) \

    ((const __EIT_entry *)((GET_EXCEPTION_DESCRIPTOR(u))->iExIdxLimit))

#ifdef __cplusplus

extern "C" {

#endif

typedef unsigned int size_t;

IMPORT_C void abort(void);

int typenameeq(const char * n1, const char * n2);

#define malloc User::Alloc

#define free User::Free

#ifdef _DEBUG

// uncomment this for diagnostic output in UDEB build

//#define _DEBUG_SYMBIAN_EH_SUPPORT

#endif

#ifdef _DEBUG_SYMBIAN_EH_SUPPORT

#define VRS_DIAGNOSTICS

#define UNWIND_ACTIVITY_DIAGNOSTICS

#define PR_DIAGNOSTICS

#define PRINTED_DIAGNOSTICS

#define CPP_DIAGNOSTICS

#endif

#define printf DebugPrintf

extern void DebugPrintf(const char *, ...);

#ifdef _DEBUG_SYMBIAN_EH_SUPPORT

#define SYMBIAN_EH_SUPPORT_PRINTF DebugPrintf

#else

#define SYMBIAN_EH_SUPPORT_PRINTF (void)

#pragma diag_suppress 174

#endif

void InitialiseSymbianSpecificUnwinderCache(uint32_t addr, _Unwind_Control_Block * ucbp);

TExceptionDescriptor * ReLoadExceptionDescriptor(uint32_t addr,_Unwind_Control_Block * ucbp);

/* Functions used to convert between segment-relative offsets

 * and absolute addresses. These are only used in unwinder.c and must be

 * compilable by a C compiler.

 */

static __inline void ValidateExceptionDescriptor(uint32_t addr, _Unwind_Control_Block * ucbp)

{

  // On entry assume ROM exception search table and exception descriptor for current frame cached in ucbp

  // see if addr is in current exception descriptor range

  TExceptionDescriptor * aEDp = GET_EXCEPTION_DESCRIPTOR(ucbp);

  if (!ADDRESS_IN_EXCEPTION_DESCRIPTOR_RANGE(addr, aEDp)) {

    aEDp = ReLoadExceptionDescriptor(addr, ucbp);

    // If there's no valid exception descriptor abort.

    if (!aEDp) {

#ifdef _DEBUG

      DebugPrintf("EH ERROR: no exception descriptor for address 0x%08x\n", addr);

      DEBUGGER_BOTTLENECK(ucbp, _UASUBSYS_UNWINDER, _UAACT_ENDING, _UAARG_ENDING_UNWINDER_LOOKUPFAILED);

#endif

      abort();

    }

  }

}

static __inline uint32_t addr_to_ER_RO_offset(uint32_t addr, _Unwind_Control_Block * ucbp)

{

  TExceptionDescriptor * aEDp = GET_EXCEPTION_DESCRIPTOR(ucbp);

  // assume ucbp has the correct exception descriptor for this offset

  return addr - GET_RO_BASE(aEDp);

}

static __inline uint32_t ER_RO_offset_to_addr(uint32_t offset, _Unwind_Control_Block * ucbp)

{

  TExceptionDescriptor * aEDp = GET_EXCEPTION_DESCRIPTOR(ucbp);

  // assume ucbp has the correct exception descriptor for this offset

  return offset + GET_RO_BASE(aEDp);

}

// This must be the same as the version in unwinder.c. However its structure is 

// governed by the EHABI and so it shouldn't change anytime soon.

typedef struct __EIT_entry {

  uint32_t fnoffset; /* Place-relative */

  uint32_t content;

} __EIT_entry;

// The Symbian unwinder uses these specific search functions rather than the generic bsearch

// to find entries in the exception index table

const __EIT_entry *SearchEITV1(uint32_t return_address_offset, const __EIT_entry *base, unsigned int nelems);

__EIT_entry *SearchEITV2(uint32_t return_address, const __EIT_entry *base, unsigned int nelems);

#ifdef __cplusplus

}

#endif

#endif // SYMBIAN_SUPPORT_H