/* -*- 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 <cstddef>
#include <dp_misc.h>
#include <dp_persmap.h>
#include <osl/diagnose.h>
#include <o3tl/safeint.hxx>
#include <rtl/byteseq.hxx>
#include <rtl/strbuf.hxx>
#include <sal/log.hxx>
using namespace ::rtl;
// the persistent map is used to manage a handful of key-value string pairs
// this implementation replaces a rather heavy-weight berkeleydb integration
// the file backing up a persistent map consists of line pairs with
// - a key string (encoded with chars 0x00..0x0F being escaped)
// - a value string (encoded with chars 0x00..0x0F being escaped)
namespace dp_misc
{
const char PmapMagic[4] = {'P','m','p','1'};
PersistentMap::PersistentMap( OUString const & url_ )
: m_MapFile( expandUnoRcUrl(url_) )
, m_bIsOpen( false )
, m_bToBeCreated( true )
, m_bIsDirty( false )
{
open();
}
PersistentMap::PersistentMap()
: m_MapFile( OUString() )
, m_bIsOpen( false )
, m_bToBeCreated( false )
, m_bIsDirty( false )
{}
PersistentMap::~PersistentMap()
{
if( m_bIsDirty )
flush();
if( m_bIsOpen )
m_MapFile.close();
}
// replace 0x00..0x0F with "%0".."%F"
// replace "%" with "%%"
static OString encodeString( const OString& rStr)
{
const char* pChar = rStr.getStr();
const sal_Int32 nLen = rStr.getLength();
sal_Int32 i = nLen;
// short circuit for the simple non-encoded case
while( --i >= 0)
{
const unsigned char c = static_cast<unsigned char>(*(pChar++));
if( c <= 0x0F )
break;
if( c == '%')
break;
}
if( i < 0)
return rStr;
// escape chars 0x00..0x0F with "%0".."%F"
OStringBuffer aEncStr( nLen + 32);
aEncStr.append( pChar - (nLen-i), nLen - i);
while( --i >= 0)
{
unsigned char c = static_cast<unsigned char>(*(pChar++));
if( c <= 0x0F )
{
aEncStr.append( '%');
c += (c <= 0x09) ? '0' : 'A'-10;
} else if( c == '%')
aEncStr.append( '%');
aEncStr.append( char(c) );
}
return aEncStr.makeStringAndClear();
}
// replace "%0".."%F" with 0x00..0x0F
// replace "%%" with "%"
static OString decodeString( const char* pEncChars, int nLen)
{
const char* pChar = pEncChars;
sal_Int32 i = nLen;
// short circuit for the simple non-encoded case
while( --i >= 0)
if( *(pChar++) == '%')
break;
if( i < 0)
return OString( pEncChars, nLen);
// replace escaped chars with their decoded counterparts
OStringBuffer aDecStr( nLen);
pChar = pEncChars;
for( i = nLen; --i >= 0;)
{
char c = *(pChar++);
// handle escaped character
if( c == '%')
{
--i;
OSL_ASSERT( i >= 0);
c = *(pChar++);
if( ('0' <= c) && (c <= '9'))
c -= '0';
else
{
OSL_ASSERT( ('A' <= c) && (c <= 'F'));
c -= ('A'-10);
}
}
aDecStr.append( c);
}
return aDecStr.makeStringAndClear();
}
void PersistentMap::open()
{
// open the existing file
sal_uInt32 const nOpenFlags = osl_File_OpenFlag_Read | osl_File_OpenFlag_Write;
const osl::File::RC rcOpen = m_MapFile.open( nOpenFlags);
m_bIsOpen = (rcOpen == osl::File::E_None);
// or create later if needed
m_bToBeCreated &= (rcOpen == osl::File::E_NOENT) && !m_bIsOpen;
if( !m_bIsOpen)
return;
readAll();
}
void PersistentMap::readAll()
{
// prepare for re-reading the map-file
m_entries.clear();
const osl::FileBase::RC nRes = m_MapFile.setPos( osl_Pos_Absolut, 0);
if (nRes != osl::FileBase::E_None)
{
SAL_WARN("desktop.deployment", "setPos failed with " << +nRes);
return;
}
// read header and check magic
char aHeaderBytes[ sizeof(PmapMagic)];
sal_uInt64 nBytesRead = 0;
m_MapFile.read( aHeaderBytes, sizeof(aHeaderBytes), nBytesRead);
OSL_ASSERT( nBytesRead == sizeof(aHeaderBytes));
if( nBytesRead != sizeof(aHeaderBytes))
return;
// check header magic
for( std::size_t i = 0; i < sizeof(PmapMagic); ++i)
if( aHeaderBytes[i] != PmapMagic[i])
return;
// read key value pairs and add them to the map
ByteSequence aKeyLine;
ByteSequence aValLine;
for(;;)
{
// read key-value line pair
// an empty key name indicates the end of the line pairs
if( m_MapFile.readLine( aKeyLine) != osl::File::E_None)
return;
if( !aKeyLine.getLength())
break;
if( m_MapFile.readLine( aValLine) != osl::File::E_None)
return;
// decode key and value strings
const OString aKeyName = decodeString( reinterpret_cast<char const *>(aKeyLine.getConstArray()), aKeyLine.getLength());
const OString aValName = decodeString( reinterpret_cast<char const *>(aValLine.getConstArray()), aValLine.getLength());
// insert key-value pair into map
add( aKeyName, aValName );
// check end-of-file status
sal_Bool bIsEOF = true;
if( m_MapFile.isEndOfFile( &bIsEOF) != osl::File::E_None )
return;
if( bIsEOF )
break;
}
m_bIsDirty = false;
}
void PersistentMap::flush()
{
if( !m_bIsDirty)
return;
if( m_bToBeCreated && !m_entries.empty())
{
const sal_uInt32 nOpenFlags = osl_File_OpenFlag_Read | osl_File_OpenFlag_Write | osl_File_OpenFlag_Create;
const osl::File::RC rcOpen = m_MapFile.open( nOpenFlags);
m_bIsOpen = (rcOpen == osl::File::E_None);
m_bToBeCreated = !m_bIsOpen;
}
if( !m_bIsOpen)
return;
// write header magic
const osl::FileBase::RC nRes = m_MapFile.setPos( osl_Pos_Absolut, 0);
if (nRes != osl::FileBase::E_None)
{
SAL_WARN("desktop.deployment", "setPos failed with " << +nRes);
return;
}
sal_uInt64 nBytesWritten = 0;
m_MapFile.write( PmapMagic, sizeof(PmapMagic), nBytesWritten);
// write key value pairs
for (auto const& entry : m_entries)
{
// write line for key
const OString aKeyString = encodeString( entry.first);
const sal_Int32 nKeyLen = aKeyString.getLength();
m_MapFile.write( aKeyString.getStr(), nKeyLen, nBytesWritten);
OSL_ASSERT( o3tl::make_unsigned(nKeyLen) == nBytesWritten);
m_MapFile.write( "\n", 1, nBytesWritten);
// write line for value
const OString aValString = encodeString( entry.second);
const sal_Int32 nValLen = aValString.getLength();
m_MapFile.write( aValString.getStr(), nValLen, nBytesWritten);
OSL_ASSERT( o3tl::make_unsigned(nValLen) == nBytesWritten);
m_MapFile.write( "\n", 1, nBytesWritten);
}
// write a file delimiter (an empty key-string)
m_MapFile.write( "\n", 1, nBytesWritten);
// truncate file here
sal_uInt64 nNewFileSize;
if( m_MapFile.getPos( nNewFileSize) == osl::File::E_None)
m_MapFile.setSize( nNewFileSize);
// flush to disk
m_MapFile.sync();
// the in-memory map now matches to the file on disk
m_bIsDirty = false;
}
bool PersistentMap::has( OString const & key ) const
{
return get( nullptr, key );
}
bool PersistentMap::get( OString * value, OString const & key ) const
{
t_string2string_map::const_iterator it = m_entries.find( key);
if( it == m_entries.end())
return false;
if( value)
*value = it->second;
return true;
}
void PersistentMap::add( OString const & key, OString const & value )
{
auto r = m_entries.emplace(key,value);
m_bIsDirty = r.second;
}
void PersistentMap::put( OString const & key, OString const & value )
{
add( key, value);
// HACK: flush now as the extension manager does not seem
// to properly destruct this object in some situations
if(m_bIsDirty)
flush();
}
bool PersistentMap::erase( OString const & key )
{
size_t nCount = m_entries.erase( key);
if( !nCount)
return false;
m_bIsDirty = true;
flush();
return true;
}
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
↑ V530 The return value of function 'append' is required to be utilized.
↑ V530 The return value of function 'append' is required to be utilized.
↑ V530 The return value of function 'append' is required to be utilized.
↑ V530 The return value of function 'append' is required to be utilized.
↑ V530 The return value of function 'append' is required to be utilized.