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libreoffice/bridges/source/cpp_uno/gcc3_ios/except.cxx
Daniel Baumann 8e63e14cf6
Adding upstream version 4:25.2.3.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
2025-06-22 16:20:04 +02:00

406 lines
14 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This file incorporates work covered by the following license notice:
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.apache.org/licenses/LICENSE-2.0 .
*/
#include "sal/config.h"
#include <cassert>
#include <new>
#include <stdio.h>
#include <string.h>
#include <typeinfo>
#include <cxxabi.h>
#include <dlfcn.h>
#include "com/sun/star/uno/RuntimeException.hpp"
#include "com/sun/star/uno/genfunc.hxx"
#include <sal/log.hxx>
#include "osl/mutex.hxx"
#include "rtl/strbuf.hxx"
#include "rtl/ustrbuf.hxx"
#include "typelib/typedescription.h"
#include "uno/any2.h"
#include <unordered_map>
#include "share.hxx"
using namespace ::osl;
using namespace ::com::sun::star::uno;
namespace CPPU_CURRENT_NAMESPACE {
namespace {
struct Fake_type_info {
virtual ~Fake_type_info() = delete;
char const * name;
};
struct Fake_class_type_info: Fake_type_info {
virtual ~Fake_class_type_info() override = delete;
};
struct Fake_si_class_type_info: Fake_class_type_info {
virtual ~Fake_si_class_type_info() override = delete;
void const * base;
};
struct Base {};
struct Derived: Base {};
std::type_info * createFake_class_type_info(char const * name) {
char * buf = new char[sizeof (Fake_class_type_info)];
*reinterpret_cast<void **>(buf) = *reinterpret_cast<void * const *>(
&typeid(Base));
// copy __cxxabiv1::__class_type_info vtable into place
Fake_class_type_info * fake = reinterpret_cast<Fake_class_type_info *>(buf);
fake->name = name;
return reinterpret_cast<std::type_info *>(
static_cast<Fake_type_info *>(fake));
}
std::type_info * createFake_si_class_type_info(
char const * name, std::type_info const * base)
{
char * buf = new char[sizeof (Fake_si_class_type_info)];
*reinterpret_cast<void **>(buf) = *reinterpret_cast<void * const *>(
&typeid(Derived));
// copy __cxxabiv1::__si_class_type_info vtable into place
Fake_si_class_type_info * fake
= reinterpret_cast<Fake_si_class_type_info *>(buf);
fake->name = name;
fake->base = base;
return reinterpret_cast<std::type_info *>(
static_cast<Fake_type_info *>(fake));
}
}
#ifdef __GNUC__
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-function"
#endif
void dummy_can_throw_anything( char const * )
{
}
#ifdef __GNUC__
#pragma GCC diagnostic pop
#endif
static OUString toUNOname( char const * p )
{
#if OSL_DEBUG_LEVEL > 1
char const * start = p;
#endif
// example: N3com3sun4star4lang24IllegalArgumentExceptionE
OUStringBuffer buf( 64 );
assert( 'N' == *p );
++p; // skip N
while ('E' != *p)
{
// read chars count
long n = (*p++ - '0');
while ('0' <= *p && '9' >= *p)
{
n *= 10;
n += (*p++ - '0');
}
buf.appendAscii( p, n );
p += n;
if ('E' != *p)
buf.append( '.' );
}
#if OSL_DEBUG_LEVEL > 1
OUString ret( buf.makeStringAndClear() );
OString c_ret( OUStringToOString( ret, RTL_TEXTENCODING_ASCII_US ) );
fprintf( stderr, "> toUNOname(): %s => %s\n", start, c_ret.getStr() );
return ret;
#else
return buf.makeStringAndClear();
#endif
}
class RTTI
{
typedef std::unordered_map< OUString, std::type_info *, OUStringHash > t_rtti_map;
Mutex m_mutex;
t_rtti_map m_rttis;
t_rtti_map m_generatedRttis;
void * m_hApp;
public:
RTTI();
~RTTI();
std::type_info * getRTTI( typelib_CompoundTypeDescription * );
};
RTTI::RTTI()
: m_hApp( dlopen( nullptr, RTLD_LAZY ) )
{
}
RTTI::~RTTI()
{
dlclose( m_hApp );
}
std::type_info * RTTI::getRTTI( typelib_CompoundTypeDescription *pTypeDescr )
{
std::type_info * rtti;
OUString const & unoName = OUString::unacquired(&pTypeDescr->aBase.pTypeName);
MutexGuard guard( m_mutex );
t_rtti_map::const_iterator iFind( m_rttis.find( unoName ) );
if (iFind == m_rttis.end())
{
// RTTI symbol
OStringBuffer buf( 64 );
buf.append( "_ZTIN" );
sal_Int32 index = 0;
do
{
OUString token( unoName.getToken( 0, '.', index ) );
buf.append( token.getLength() );
OString c_token( OUStringToOString( token, RTL_TEXTENCODING_ASCII_US ) );
buf.append( c_token );
}
while (index >= 0);
buf.append( 'E' );
OString symName( buf.makeStringAndClear() );
rtti = static_cast<std::type_info *>(dlsym( m_hApp, symName.getStr() ));
if (rtti)
{
std::pair< t_rtti_map::iterator, bool > insertion(
m_rttis.insert( t_rtti_map::value_type( unoName, rtti ) ) );
SAL_WARN_IF( !insertion.second,
"bridges",
"inserting new rtti failed" );
}
else
{
// try to lookup the symbol in the generated rtti map
t_rtti_map::const_iterator iFind2( m_generatedRttis.find( unoName ) );
if (iFind2 == m_generatedRttis.end())
{
// we must generate it !
// symbol and rtti-name is nearly identical,
// the symbol is prefixed with _ZTI
char * rttiName = strdup(symName.getStr() + 4);
if (rttiName == nullptr) {
throw std::bad_alloc();
}
#if OSL_DEBUG_LEVEL > 1
fprintf( stderr,"generated rtti for %s\n", rttiName );
#endif
if (pTypeDescr->pBaseTypeDescription)
{
// ensure availability of base
std::type_info * base_rtti = getRTTI(
pTypeDescr->pBaseTypeDescription );
rtti = createFake_si_class_type_info(rttiName, base_rtti);
}
else
{
rtti = createFake_class_type_info(rttiName);
}
std::pair< t_rtti_map::iterator, bool > insertion(
m_generatedRttis.insert( t_rtti_map::value_type( unoName, rtti ) ) );
SAL_WARN_IF( !insertion.second,
"bridges",
"inserting new generated rtti failed" );
}
else // taking already generated rtti
{
rtti = iFind2->second;
}
}
}
else
{
rtti = iFind->second;
}
return rtti;
}
static void deleteException( void * pExc )
{
__cxa_exception const * header = static_cast<__cxa_exception const *>(pExc) - 1;
// The libcxxabi commit
// <http://llvm.org/viewvc/llvm-project?view=revision&revision=303175>
// "[libcxxabi] Align unwindHeader on a double-word boundary" towards
// LLVM 5.0 changed the size of __cxa_exception by adding
//
// __attribute__((aligned))
//
// to the final member unwindHeader, on x86-64 effectively adding a hole of
// size 8 in front of that member (changing its offset from 88 to 96,
// sizeof(__cxa_exception) from 120 to 128, and alignof(__cxa_exception)
// from 8 to 16); a hack to dynamically determine whether we run against a
// LLVM 5 libcxxabi is to look at the exceptionDestructor member, which must
// point to this function (the use of __cxa_exception in fillUnoException is
// unaffected, as it only accesses members towards the start of the struct,
// through a pointer known to actually point at the start). The libcxxabi commit
// <https://github.com/llvm/llvm-project/commit/9ef1daa46edb80c47d0486148c0afc4e0d83ddcf>
// "Insert padding before the __cxa_exception header to ensure the thrown" in LLVM 6
// removes the need for this hack, so it can be removed again once we can be sure that we only
// run against libcxxabi from LLVM >= 6:
if (header->exceptionDestructor != &deleteException) {
header = reinterpret_cast<__cxa_exception const *>(
reinterpret_cast<char const *>(header) - 8);
assert(header->exceptionDestructor == &deleteException);
}
typelib_TypeDescription * pTD = nullptr;
OUString unoName( toUNOname( header->exceptionType->name() ) );
::typelib_typedescription_getByName( &pTD, unoName.pData );
assert(pTD && "### unknown exception type! leaving out destruction => leaking!!!");
if (pTD)
{
::uno_destructData( pExc, pTD, cpp_release );
::typelib_typedescription_release( pTD );
}
}
void raiseException( uno_Any * pUnoExc, uno_Mapping * pUno2Cpp )
{
#if OSL_DEBUG_LEVEL > 1
OString cstr(
OUStringToOString(
OUString::unacquired( &pUnoExc->pType->pTypeName ),
RTL_TEXTENCODING_ASCII_US ) );
fprintf( stderr, "> uno exception occurred: %s\n", cstr.getStr() );
#endif
void * pCppExc;
std::type_info * rtti;
{
// construct cpp exception object
typelib_TypeDescription * pTypeDescr = nullptr;
TYPELIB_DANGER_GET( &pTypeDescr, pUnoExc->pType );
assert(pTypeDescr);
if (! pTypeDescr)
{
throw RuntimeException(
"cannot get typedescription for type " +
OUString::unacquired( &pUnoExc->pType->pTypeName ) );
}
pCppExc = __cxxabiv1::__cxa_allocate_exception( pTypeDescr->nSize );
::uno_copyAndConvertData( pCppExc, pUnoExc->pData, pTypeDescr, pUno2Cpp );
// destruct uno exception
::uno_any_destruct( pUnoExc, nullptr );
// avoiding locked counts
static RTTI rtti_data;
rtti = rtti_data.getRTTI(reinterpret_cast<typelib_CompoundTypeDescription*>(pTypeDescr));
TYPELIB_DANGER_RELEASE( pTypeDescr );
assert(rtti && "### no rtti for throwing exception!");
if (! rtti)
{
throw RuntimeException(
"no rtti for type " +
OUString::unacquired( &pUnoExc->pType->pTypeName ) );
}
}
// void __cxa_throw(void* thrown_exception,
// struct std::type_info * tinfo,
// void (*dest)(void*));
__cxxabiv1::__cxa_throw( pCppExc, rtti, deleteException );
}
void fillUnoException(uno_Any * pUnoExc, uno_Mapping * pCpp2Uno)
{
__cxa_exception * header = __cxxabiv1::__cxa_get_globals()->caughtExceptions;
if (! header)
{
RuntimeException aRE( "no exception header!" );
Type const & rType = cppu::UnoType<decltype(aRE)>::get();
uno_type_any_constructAndConvert( pUnoExc, &aRE, rType.getTypeLibType(), pCpp2Uno );
SAL_WARN("bridges", aRE.Message);
return;
}
// Very bad HACK to find out whether we run against a libcxxabi that has a new
// __cxa_exception::reserved member at the start, introduced with LLVM 10
// <https://github.com/llvm/llvm-project/commit/674ec1eb16678b8addc02a4b0534ab383d22fa77>
// "[libcxxabi] Insert padding in __cxa_exception struct for compatibility". The layout of the
// start of __cxa_exception is
//
// [8 byte void *reserve]
// 8 byte size_t referenceCount
//
// where the (bad, hacky) assumption is that reserve (if present) is null
// (__cxa_allocate_exception in at least LLVM 11 zero-fills the object, and nothing actively
// sets reserve) while referenceCount is non-null (__cxa_throw sets it to 1, and
// __cxa_decrement_exception_refcount destroys the exception as soon as it drops to 0; for a
// __cxa_dependent_exception, the referenceCount member is rather
//
// 8 byte void* primaryException
//
// but which also will always be set to a non-null value in __cxa_rethrow_primary_exception).
// As described in the definition of __cxa_exception
// (bridges/source/cpp_uno/gcc3_macosx_x86-64/share.hxx), this hack (together with the "#if 0"
// there) can be dropped once we can be sure that we only run against new libcxxabi that has the
// reserve member:
if (*reinterpret_cast<void **>(header) == nullptr) {
header = reinterpret_cast<__cxa_exception *>(reinterpret_cast<void **>(header) + 1);
}
std::type_info *exceptionType = __cxxabiv1::__cxa_current_exception_type();
typelib_TypeDescription * pExcTypeDescr = nullptr;
OUString unoName( toUNOname( exceptionType->name() ) );
#if OSL_DEBUG_LEVEL > 1
OString cstr_unoName( OUStringToOString( unoName, RTL_TEXTENCODING_ASCII_US ) );
fprintf( stderr, "> c++ exception occurred: %s\n", cstr_unoName.getStr() );
#endif
typelib_typedescription_getByName( &pExcTypeDescr, unoName.pData );
if (nullptr == pExcTypeDescr)
{
RuntimeException aRE( "exception type not found: " + unoName );
Type const & rType = cppu::UnoType<decltype(aRE)>::get();
uno_type_any_constructAndConvert( pUnoExc, &aRE, rType.getTypeLibType(), pCpp2Uno );
SAL_WARN("bridges", aRE.Message);
}
else
{
// construct uno exception any
uno_any_constructAndConvert( pUnoExc, header->adjustedPtr, pExcTypeDescr, pCpp2Uno );
typelib_typedescription_release( pExcTypeDescr );
}
}
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */