scummvm/engines/neverhood/saveload.cpp
Adrian Frühwirth 00e59a3122 ALL: Load savegame thumbnail only when necessary
This commit introduces the following changes:

1. Graphics::loadThumbnail()

   Now returns a boolean and takes a new argument skipThumbnail which
   defaults to false. In case of true, loadThumbnail() reads past the
   thumbnail data in the input stream instead of actually loading the
   thumbnail. This simplifies savegame handling where, up until now,
   many engines always read the whole savegame metadata (including
   the thumbnail) and then threw away the thumbnail when not needed
   (which is in almost all cases, the most common exception being
   MetaEngine::querySaveMetaInfos() which is responsible for loading
   savegame metadata for displaying it in the GUI launcher.

2. readSavegameHeader()

   Engines which already implement such a method (name varies) now take
   a new argument skipThumbnail (default: true) which is passed
   through to loadThumbnail(). This means that the default case for
   readSavegameHeader() is now _not_ loading the thumbnail from a
   savegame and just reading past it. In those cases, e.g.
   querySaveMetaInfos(), where we actually are interested in loading
   the thumbnail readSavegameHeader() needs to explicitely be called
   with skipThumbnail == false.

   Engines whose readSavegameHeader() (name varies) already takes an
   argument loadThumbnail have been adapted to have a similar
   prototype and semantics.
   I.e. readSaveHeader(in, loadThumbnail, header) now is
   readSaveHeader(in, header, skipThumbnail).

3. Error handling

   Engines which previously did not check the return value of
   readSavegameHeader() (name varies) now do so ensuring that possibly
   broken savegames (be it a broken thumbnail or something else) don't
   make it into the GUI launcher list in the first place.
2018-04-07 09:26:20 +02:00

165 lines
5.0 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#include "common/savefile.h"
#include "graphics/thumbnail.h"
#include "neverhood/neverhood.h"
#include "neverhood/gamemodule.h"
#include "neverhood/gamevars.h"
namespace Neverhood {
#define NEVERHOOD_SAVEGAME_VERSION 0
WARN_UNUSED_RESULT NeverhoodEngine::kReadSaveHeaderError NeverhoodEngine::readSaveHeader(Common::SeekableReadStream *in, SaveHeader &header, bool skipThumbnail) {
header.version = in->readUint32LE();
if (header.version > NEVERHOOD_SAVEGAME_VERSION)
return kRSHEInvalidVersion;
byte descriptionLen = in->readByte();
header.description = "";
while (descriptionLen--)
header.description += (char)in->readByte();
if (!Graphics::loadThumbnail(*in, header.thumbnail, skipThumbnail)) {
return kRSHEIoError;
}
// Not used yet, reserved for future usage
header.gameID = in->readByte();
header.flags = in->readUint32LE();
header.saveDate = in->readUint32LE();
header.saveTime = in->readUint32LE();
header.playTime = in->readUint32LE();
return ((in->eos() || in->err()) ? kRSHEIoError : kRSHENoError);
}
bool NeverhoodEngine::savegame(const char *filename, const char *description) {
Common::OutSaveFile *out;
if (!(out = g_system->getSavefileManager()->openForSaving(filename))) {
warning("Can't create file '%s', game not saved", filename);
return false;
}
TimeDate curTime;
g_system->getTimeAndDate(curTime);
// Header start
out->writeUint32LE(NEVERHOOD_SAVEGAME_VERSION);
byte descriptionLen = strlen(description);
out->writeByte(descriptionLen);
out->write(description, descriptionLen);
Graphics::saveThumbnail(*out);
// Not used yet, reserved for future usage
out->writeByte(0);
out->writeUint32LE(0);
uint32 saveDate = ((curTime.tm_mday & 0xFF) << 24) | (((curTime.tm_mon + 1) & 0xFF) << 16) | ((curTime.tm_year + 1900) & 0xFFFF);
uint32 saveTime = ((curTime.tm_hour & 0xFF) << 16) | (((curTime.tm_min) & 0xFF) << 8) | ((curTime.tm_sec) & 0xFF);
uint32 playTime = g_engine->getTotalPlayTime() / 1000;
out->writeUint32LE(saveDate);
out->writeUint32LE(saveTime);
out->writeUint32LE(playTime);
// Header end
_gameVars->setGlobalVar(V_CURRENT_SCENE, _gameState.sceneNum);
_gameVars->setGlobalVar(V_CURRENT_SCENE_WHICH, _gameState.which);
_gameVars->saveState(out);
out->finalize();
delete out;
return true;
}
bool NeverhoodEngine::loadgame(const char *filename) {
Common::InSaveFile *in;
if (!(in = g_system->getSavefileManager()->openForLoading(filename))) {
warning("Can't open file '%s', game not loaded", filename);
return false;
}
SaveHeader header;
kReadSaveHeaderError errorCode = readSaveHeader(in, header);
if (errorCode != kRSHENoError) {
warning("Error loading savegame '%s'", filename);
delete in;
return false;
}
g_engine->setTotalPlayTime(header.playTime * 1000);
_gameVars->loadState(in);
_gameState.sceneNum = _gameVars->getGlobalVar(V_CURRENT_SCENE);
_gameState.which = _gameVars->getGlobalVar(V_CURRENT_SCENE_WHICH);
_gameModule->requestRestoreGame();
delete in;
return true;
}
Common::Error NeverhoodEngine::loadGameState(int slot) {
const char *fileName = getSavegameFilename(slot);
if (!loadgame(fileName))
return Common::kReadingFailed;
return Common::kNoError;
}
Common::Error NeverhoodEngine::saveGameState(int slot, const Common::String &description) {
const char *fileName = getSavegameFilename(slot);
if (!savegame(fileName, description.c_str()))
return Common::kWritingFailed;
return Common::kNoError;
}
Common::Error NeverhoodEngine::removeGameState(int slot) {
Common::SaveFileManager *saveFileMan = g_system->getSavefileManager();
Common::String filename = Neverhood::NeverhoodEngine::getSavegameFilename(_targetName, slot);
saveFileMan->removeSavefile(filename.c_str());
return Common::kNoError;
}
const char *NeverhoodEngine::getSavegameFilename(int num) {
static Common::String filename;
filename = getSavegameFilename(_targetName, num);
return filename.c_str();
}
Common::String NeverhoodEngine::getSavegameFilename(const Common::String &target, int num) {
assert(num >= 0 && num <= 999);
return Common::String::format("%s.%03d", target.c_str(), num);
}
} // End of namespace Neverhood