diff options
Diffstat (limited to 'bridges/source/cpp_uno/gcc3_linux_x86-64/except.cxx')
-rw-r--r-- | bridges/source/cpp_uno/gcc3_linux_x86-64/except.cxx | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/bridges/source/cpp_uno/gcc3_linux_x86-64/except.cxx b/bridges/source/cpp_uno/gcc3_linux_x86-64/except.cxx new file mode 100644 index 000000000..2a92dba37 --- /dev/null +++ b/bridges/source/cpp_uno/gcc3_linux_x86-64/except.cxx @@ -0,0 +1,260 @@ +/* -*- 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 <stdio.h> +#include <string.h> + +#include <rtl/ustrbuf.hxx> +#include <sal/log.hxx> + +#include <com/sun/star/uno/genfunc.hxx> +#include <com/sun/star/uno/RuntimeException.hpp> +#include <typelib/typedescription.hxx> +#include <uno/any2.h> + +#include "rtti.hxx" +#include "share.hxx" + + +using namespace ::std; +using namespace ::com::sun::star::uno; +using namespace ::__cxxabiv1; + + +namespace CPPU_CURRENT_NAMESPACE +{ + +static OUString toUNOname( char const * p ) +{ +#if OSL_DEBUG_LEVEL > 1 + char const * start = p; +#endif + + // example: N3com3sun4star4lang24IllegalArgumentExceptionE + + OUStringBuffer buf( 64 ); + assert( *p == 'N' ); + ++p; // skip N + + while (*p != 'E') + { + // read chars count + int n = *p++ - '0'; + while ('0' <= *p && '9' >= *p) + { + n *= 10; + n += (*p++ - '0'); + } + buf.appendAscii( p, n ); + p += n; + if (*p != 'E') + 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 +} + +extern "C" { +static void _GLIBCXX_CDTOR_CALLABI deleteException( void * pExc ) +{ + __cxxabiv1::__cxa_exception const * header = static_cast<__cxxabiv1::__cxa_exception const *>(pExc) - 1; +#if defined _LIBCPPABI_VERSION // detect libc++abi + // First, 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); the "header1" hack below 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 the "header1" hack can be removed again once we can be + // sure that we only run against libcxxabi from LLVM >= 6. + // + // Second, the libcxxabi commit + // <https://github.com/llvm/llvm-project/commit/674ec1eb16678b8addc02a4b0534ab383d22fa77> + // "[libcxxabi] Insert padding in __cxa_exception struct for compatibility" in LLVM 10 changed + // the layout of the start of __cxa_exception to + // + // [8 byte void *reserve] + // 8 byte size_t referenceCount + // + // so the "header2" hack below to dynamically determine whether we run against a LLVM >= 10 + // libcxxabi is to look whether the exceptionDestructor (with its known value) has increased its + // offset by 8. As described in the definition of __cxa_exception + // (bridges/source/cpp_uno/gcc3_linux_x86-64/share.hxx), the "header2" hack (together with the + // "#if 0" in the definition of __cxa_exception and the corresponding hack in fillUnoException) + // can be dropped once we can be sure that we only run against new libcxxabi that has the + // reserve member. + if (header->exceptionDestructor != &deleteException) { + auto const header1 = reinterpret_cast<__cxa_exception const *>( + reinterpret_cast<char const *>(header) - 8); + if (header1->exceptionDestructor == &deleteException) { + header = header1; + } else { + auto const header2 = reinterpret_cast<__cxa_exception const *>( + reinterpret_cast<char const *>(header) + 8); + if (header2->exceptionDestructor == &deleteException) { + header = header2; + } else { + assert(false); + } + } + } +#endif + 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; + 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 + rtti = x86_64::getRtti(*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 ) ); + } + } + + __cxxabiv1::__cxa_throw( pCppExc, rtti, deleteException ); +} + +void fillUnoException(uno_Any * pUnoExc, uno_Mapping * pCpp2Uno) +{ + __cxxabiv1::__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; + } + +#if defined _LIBCPPABI_VERSION // detect libc++abi + // 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_linux_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<__cxxabiv1::__cxa_exception*>(reinterpret_cast<void **>(header) + 1); + } +#endif + + 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 (pExcTypeDescr == nullptr) + { + 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: */ |