/*************************************************************************
 *
 *  OpenOffice.org - a multi-platform office productivity suite
 *
 *  $RCSfile: vtablefactory.cxx,v $
 *
 *  $Revision: 1.7 $
 *
 *  last change: $Author: obo $ $Date: 2006-09-16 15:56:54 $
 *
 *  The Contents of this file are made available subject to
 *  the terms of GNU Lesser General Public License Version 2.1.
 *
 *
 *    GNU Lesser General Public License Version 2.1
 *    =============================================
 *    Copyright 2005 by Sun Microsystems, Inc.
 *    901 San Antonio Road, Palo Alto, CA 94303, USA
 *
 *    This library is free software; you can redistribute it and/or
 *    modify it under the terms of the GNU Lesser General Public
 *    License version 2.1, as published by the Free Software Foundation.
 *
 *    This library is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *    Lesser General Public License for more details.
 *
 *    You should have received a copy of the GNU Lesser General Public
 *    License along with this library; if not, write to the Free Software
 *    Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 *    MA  02111-1307  USA
 *
 ************************************************************************/

// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_bridges.hxx"

#include "bridges/cpp_uno/shared/vtablefactory.hxx"

#include "guardedarray.hxx"

#include "bridges/cpp_uno/shared/vtables.hxx"

#include "osl/diagnose.h"
#include "osl/mutex.hxx"
#include "rtl/alloc.h"
#include "rtl/ustring.hxx"
#include "sal/types.h"
#include "typelib/typedescription.hxx"

#include <hash_map>
#include <new>
#include <vector>

#if defined SAL_UNX
#include <unistd.h>
#include <sys/mman.h>
#elif defined SAL_W32
#define WIN32_LEAN_AND_MEAN
#pragma warning(push,1) // disable warnings within system headers
#include <windows.h>
#pragma warning(pop)
#else
#error Unsupported platform
#endif

using bridges::cpp_uno::shared::VtableFactory;

namespace {

extern "C" void * SAL_CALL allocExec(rtl_arena_type *, sal_Size * size) {
    sal_Size pagesize;
#if defined SAL_UNX
#if defined FREEBSD || defined NETBSD
    pagesize = getpagesize();
#else
    pagesize = sysconf(_SC_PAGESIZE);
#endif
#elif defined SAL_W32
    SYSTEM_INFO info;
    GetSystemInfo(&info);
    pagesize = info.dwPageSize;
#endif
    sal_Size n = (*size + (pagesize - 1)) & ~(pagesize - 1);
    void * p;
#if defined SAL_UNX
    p = mmap(
        0, n, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1,
        0);
    if (p == MAP_FAILED) {
        p = 0;
    }
    else if (mprotect (static_cast<char*>(p), n, PROT_READ | PROT_WRITE | PROT_EXEC) == -1)
    {
        munmap (static_cast<char*>(p), n);
        p = 0;
    }
#elif defined SAL_W32
    p = VirtualAlloc(0, n, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
#endif
    if (p != 0) {
        *size = n;
    }
    return p;
}

extern "C" void SAL_CALL freeExec(
    rtl_arena_type *, void * address, sal_Size size)
{
#if defined SAL_UNX
    munmap(static_cast< char * >(address), size);
#elif defined SAL_W32
    (void) size; // unused
    VirtualFree(address, 0, MEM_RELEASE);
#endif
}

}

class VtableFactory::GuardedBlocks: public std::vector< Block > {
public:
    GuardedBlocks(VtableFactory const & factory):
        m_factory(factory), m_guarded(true) {}

    ~GuardedBlocks();

    void unguard() { m_guarded = false; }

private:
    GuardedBlocks(GuardedBlocks &); // not implemented
    void operator =(GuardedBlocks); // not implemented

    VtableFactory const & m_factory;
    bool m_guarded;
};

VtableFactory::GuardedBlocks::~GuardedBlocks() {
    if (m_guarded) {
        for (iterator i(begin()); i != end(); ++i) {
            m_factory.freeBlock(*i);
        }
    }
}

class VtableFactory::BaseOffset {
public:
    BaseOffset(typelib_InterfaceTypeDescription * type) { calculate(type, 0); }

    sal_Int32 getFunctionOffset(rtl::OUString const & name) const
    { return m_map.find(name)->second; }

private:
    sal_Int32 calculate(
        typelib_InterfaceTypeDescription * type, sal_Int32 offset);

    typedef std::hash_map< rtl::OUString, sal_Int32, rtl::OUStringHash > Map;

    Map m_map;
};

sal_Int32 VtableFactory::BaseOffset::calculate(
    typelib_InterfaceTypeDescription * type, sal_Int32 offset)
{
    rtl::OUString name(type->aBase.pTypeName);
    if (m_map.find(name) == m_map.end()) {
        for (sal_Int32 i = 0; i < type->nBaseTypes; ++i) {
            offset = calculate(type->ppBaseTypes[i], offset);
        }
        m_map.insert(Map::value_type(name, offset));
        typelib_typedescription_complete(
            reinterpret_cast< typelib_TypeDescription ** >(&type));
        offset += bridges::cpp_uno::shared::getLocalFunctions(type);
    }
    return offset;
}

VtableFactory::VtableFactory(): m_arena(
    rtl_arena_create(
        "bridges::cpp_uno::shared::VtableFactory",
        sizeof (void *), // to satisfy alignment requirements
        0, reinterpret_cast< rtl_arena_type * >(-1), allocExec, freeExec, 0))
{
    if (m_arena == 0) {
        throw std::bad_alloc();
    }
}

VtableFactory::~VtableFactory() {
    {
        osl::MutexGuard guard(m_mutex);
        for (Map::iterator i(m_map.begin()); i != m_map.end(); ++i) {
            for (sal_Int32 j = 0; j < i->second.count; ++j) {
                freeBlock(i->second.blocks[j]);
            }
            delete[] i->second.blocks;
        }
    }
    rtl_arena_destroy(m_arena);
}

VtableFactory::Vtables VtableFactory::getVtables(
    typelib_InterfaceTypeDescription * type)
{
    rtl::OUString name(type->aBase.pTypeName);
    osl::MutexGuard guard(m_mutex);
    Map::iterator i(m_map.find(name));
    if (i == m_map.end()) {
        GuardedBlocks blocks(*this);
        createVtables(blocks, BaseOffset(type), type, true);
        Vtables vtables;
        OSL_ASSERT(blocks.size() <= SAL_MAX_INT32);
        vtables.count = static_cast< sal_Int32 >(blocks.size());
        bridges::cpp_uno::shared::GuardedArray< Block > guardedBlocks(
            new Block[vtables.count]);
        vtables.blocks = guardedBlocks.get();
        for (sal_Int32 j = 0; j < vtables.count; ++j) {
            vtables.blocks[j] = blocks[j];
        }
        i = m_map.insert(Map::value_type(name, vtables)).first;
        guardedBlocks.release();
        blocks.unguard();
    }
    return i->second;
}

void VtableFactory::freeBlock(Block const & block) const {
    rtl_arena_free(m_arena, block.start, block.size);
}

void VtableFactory::createVtables(
    GuardedBlocks & blocks, BaseOffset const & baseOffset,
    typelib_InterfaceTypeDescription * type, bool includePrimary) const
{
    if (includePrimary) {
        sal_Int32 slotCount
            = bridges::cpp_uno::shared::getPrimaryFunctions(type);
        Block block;
        block.size = getBlockSize(slotCount);
        block.start = rtl_arena_alloc(m_arena, &block.size);
        if (block.start == 0) {
            throw std::bad_alloc();
        }
        try {
            void ** slots = initializeBlock(block.start) + slotCount;
            unsigned char * codeBegin =
                reinterpret_cast< unsigned char * >(slots);
            unsigned char * code = codeBegin;
            sal_Int32 vtableOffset = blocks.size() * sizeof (void **);
            for (typelib_InterfaceTypeDescription const * type2 = type;
                 type2 != 0; type2 = type2->pBaseTypeDescription)
            {
                sal_Int32 functionCount
                    = bridges::cpp_uno::shared::getLocalFunctions(type2);
                slots -= functionCount;
                code = addLocalFunctions(
                    slots, code, type2,
                    baseOffset.getFunctionOffset(type2->aBase.pTypeName),
                    functionCount, vtableOffset);
            }
            flushCode(codeBegin, code);
            blocks.push_back(block);
        } catch (...) {
            freeBlock(block);
            throw;
        }
    }
    for (sal_Int32 i = 0; i < type->nBaseTypes; ++i) {
        createVtables(blocks, baseOffset, type->ppBaseTypes[i], i != 0);
    }
}