libreoffice-online/loolwsd/TileCache.cpp
Tor Lillqvist 97adaf935b Don't let 'canceltiles' messages affect slide thumbnails being rendered
Document that the 'id' parameter of a 'tile' message is not (should
not be) used for anything except slide thumbnails.

If we later need some more generic way to distinguish the purpose of
tile requests, need to come up with something else, like a 'purpose'
parameter.
2016-10-04 13:31:36 +03:00

513 lines
17 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
/*
* 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/.
*/
#include "TileCache.hpp"
#include "config.h"
#include <cassert>
#include <climits>
#include <cstdio>
#include <fstream>
#include <iostream>
#include <memory>
#include <mutex>
#include <sstream>
#include <string>
#include <vector>
#include <Poco/DigestEngine.h>
#include <Poco/DirectoryIterator.h>
#include <Poco/Exception.h>
#include <Poco/File.h>
#include <Poco/Path.h>
#include <Poco/StringTokenizer.h>
#include <Poco/Timestamp.h>
#include <Poco/URI.h>
#include "ClientSession.hpp"
#include "Common.hpp"
#include "LOOLProtocol.hpp"
#include "Unit.hpp"
#include "Util.hpp"
using Poco::DirectoryIterator;
using Poco::File;
using Poco::StringTokenizer;
using Poco::Timestamp;
using namespace LOOLProtocol;
TileCache::TileCache(const std::string& docURL,
const Timestamp& modifiedTime,
const std::string& cacheDir) :
_docURL(docURL),
_cacheDir(cacheDir),
_cacheMutex(),
_tilesBeingRenderedMutex()
{
Log::info() << "TileCache ctor for uri [" << _docURL
<< "] modifiedTime=" << (modifiedTime.raw()/1000000)
<< " getLastModified()=" << (getLastModified().raw()/1000000) << Log::end;
File directory(_cacheDir);
if (directory.exists() &&
(getLastModified() < modifiedTime ||
getTextFile("unsaved.txt") != ""))
{
// Document changed externally or modifications were not saved after all. Cache not useful.
Util::removeFile(_cacheDir, true);
Log::info("Completely cleared tile cache: " + _cacheDir);
}
File(_cacheDir).createDirectories();
saveLastModified(modifiedTime);
}
TileCache::~TileCache()
{
Log::info("~TileCache dtor for uri [" + _docURL + "].");
}
/// Tracks the rendering of a given tile
/// to avoid duplication and help clock
/// rendering latency.
struct TileCache::TileBeingRendered
{
std::vector<std::weak_ptr<ClientSession>> _subscribers;
TileBeingRendered(const std::string& cachedName, const TileDesc& tile)
: _startTime(std::chrono::steady_clock::now()),
_tile(tile),
_cachedName(cachedName)
{
}
const TileDesc& getTile() const { return _tile; }
const std::string& getCacheName() const { return _cachedName; }
int getVersion() const { return _tile.getVersion(); }
void setVersion(int version) { _tile.setVersion(version); }
std::chrono::steady_clock::time_point getStartTime() const { return _startTime; }
double getElapsedTimeMs() const { return std::chrono::duration_cast<std::chrono::milliseconds>
(std::chrono::steady_clock::now() - _startTime).count(); }
void resetStartTime()
{
_startTime = std::chrono::steady_clock::now();
}
private:
std::chrono::steady_clock::time_point _startTime;
TileDesc _tile;
std::string _cachedName;
};
std::shared_ptr<TileCache::TileBeingRendered> TileCache::findTileBeingRendered(const TileDesc& tileDesc)
{
const std::string cachedName = cacheFileName(tileDesc);
Util::assertIsLocked(_tilesBeingRenderedMutex);
const auto tile = _tilesBeingRendered.find(cachedName);
return (tile != _tilesBeingRendered.end() ? tile->second : nullptr);
}
void TileCache::forgetTileBeingRendered(const TileDesc& tile)
{
const std::string cachedName = cacheFileName(tile);
Util::assertIsLocked(_tilesBeingRenderedMutex);
_tilesBeingRendered.erase(cachedName);
}
std::unique_ptr<std::fstream> TileCache::lookupTile(const TileDesc& tile)
{
const std::string fileName = _cacheDir + "/" + cacheFileName(tile);
std::unique_ptr<std::fstream> result(new std::fstream(fileName, std::ios::in));
UnitWSD::get().lookupTile(tile.getPart(), tile.getWidth(), tile.getHeight(),
tile.getTilePosX(), tile.getTilePosY(),
tile.getTileWidth(), tile.getTileHeight(), result);
if (result && result->is_open())
{
Log::trace("Found cache tile: " + fileName);
return result;
}
return nullptr;
}
void TileCache::saveTileAndNotify(const TileDesc& tile, const char *data, const size_t size)
{
std::unique_lock<std::mutex> lock(_tilesBeingRenderedMutex);
std::shared_ptr<TileBeingRendered> tileBeingRendered = findTileBeingRendered(tile);
// Save to disk.
const auto cachedName = (tileBeingRendered ? tileBeingRendered->getCacheName()
: cacheFileName(tile));
// Ignore if we can't save the tile, things will work anyway, but slower. An error indication
// has been supposed to be sent to all users in that case.
const auto fileName = _cacheDir + "/" + cachedName;
if (Util::saveDataToFileSafely(fileName, data, size))
Log::trace() << "Saved cache tile: " << fileName << Log::end;
// Notify subscribers, if any.
if (tileBeingRendered)
{
if (!tileBeingRendered->_subscribers.empty())
{
std::string response = tile.serialize("tile:");
Log::debug("Sending tile message to subscribers: " + response);
response += '\n';
std::vector<char> output;
output.reserve(static_cast<size_t>(4) * tile.getWidth() * tile.getHeight());
output.resize(response.size());
std::memcpy(output.data(), response.data(), response.size());
const auto pos = output.size();
output.resize(pos + size);
std::memcpy(output.data() + pos, data, size);
for (const auto& i: tileBeingRendered->_subscribers)
{
auto subscriber = i.lock();
if (subscriber)
{
try
{
subscriber->sendBinaryFrame(output.data(), output.size());
}
catch (const std::exception& ex)
{
Log::warn("Failed to send tile to " + subscriber->getName() + ": " + ex.what());
}
}
}
}
else
{
Log::debug("No subscribers for: " + cachedName);
}
// Remove subscriptions.
if (tileBeingRendered->getVersion() <= tile.getVersion())
{
Log::debug() << "STATISTICS: tile " << tile.getVersion() << " internal roundtrip "
<< tileBeingRendered->getElapsedTimeMs() << " ms." << Log::end;
_tilesBeingRendered.erase(cachedName);
}
}
else
{
Log::debug("No subscribers for: " + cachedName);
}
}
std::string TileCache::getTextFile(const std::string& fileName)
{
const std::string fullFileName = _cacheDir + "/" + fileName;
std::fstream textStream(fullFileName, std::ios::in);
if (!textStream.is_open())
{
Log::info("Could not open " + fullFileName);
return "";
}
std::vector<char> buffer;
textStream.seekg(0, std::ios_base::end);
std::streamsize size = textStream.tellg();
buffer.resize(size);
textStream.seekg(0, std::ios_base::beg);
textStream.read(buffer.data(), size);
textStream.close();
if (buffer.size() > 0 && buffer.back() == '\n')
buffer.pop_back();
std::string result = std::string(buffer.data(), buffer.size());
Log::info("Read '" + LOOLProtocol::getAbbreviatedMessage(result.c_str(), result.size()) + "' from " + fullFileName);
return result;
}
void TileCache::saveTextFile(const std::string& text, const std::string& fileName)
{
const std::string fullFileName = _cacheDir + "/" + fileName;
std::fstream textStream(fullFileName, std::ios::out);
if (!textStream.is_open())
{
Log::error("Could not save '" + text + "' to " + fullFileName);
return;
}
else
{
Log::info("Saving '" + LOOLProtocol::getAbbreviatedMessage(text.c_str(), text.size()) + "' to " + fullFileName);
}
textStream << text << std::endl;
textStream.close();
}
void TileCache::setUnsavedChanges(bool state)
{
if (state)
saveTextFile("1", "unsaved.txt");
else
removeFile("unsaved.txt");
}
void TileCache::saveRendering(const std::string& name, const std::string& dir, const char *data, size_t size)
{
// can fonts be invalidated?
const std::string dirName = _cacheDir + "/" + dir;
File(dirName).createDirectories();
const std::string fileName = dirName + "/" + name;
Util::saveDataToFileSafely(fileName, data, size);
}
std::unique_ptr<std::fstream> TileCache::lookupRendering(const std::string& name, const std::string& dir)
{
const std::string dirName = _cacheDir + "/" + dir;
const std::string fileName = dirName + "/" + name;
File directory(dirName);
if (directory.exists() && directory.isDirectory() && File(fileName).exists())
{
std::unique_ptr<std::fstream> result(new std::fstream(fileName, std::ios::in));
return result;
}
return nullptr;
}
void TileCache::invalidateTiles(int part, int x, int y, int width, int height)
{
Log::trace() << "Removing invalidated tiles: part: " << part
<< ", x: " << x << ", y: " << y
<< ", width: " << width
<< ", height: " << height << Log::end;
File dir(_cacheDir);
std::unique_lock<std::mutex> lock(_cacheMutex);
std::unique_lock<std::mutex> lockSubscribers(_tilesBeingRenderedMutex);
if (dir.exists() && dir.isDirectory())
{
for (auto tileIterator = DirectoryIterator(dir); tileIterator != DirectoryIterator(); ++tileIterator)
{
const std::string fileName = tileIterator.path().getFileName();
if (intersectsTile(fileName, part, x, y, width, height))
{
Log::debug("Removing tile: " + tileIterator.path().toString());
Util::removeFile(tileIterator.path());
}
}
}
}
void TileCache::invalidateTiles(const std::string& tiles)
{
StringTokenizer tokens(tiles, " ", StringTokenizer::TOK_IGNORE_EMPTY | StringTokenizer::TOK_TRIM);
assert(tokens[0] == "invalidatetiles:");
if (tokens.count() == 2 && tokens[1] == "EMPTY")
{
invalidateTiles(-1, 0, 0, INT_MAX, INT_MAX);
}
else
{
int part, x, y, width, height;
if (tokens.count() == 6 &&
getTokenInteger(tokens[1], "part", part) &&
getTokenInteger(tokens[2], "x", x) &&
getTokenInteger(tokens[3], "y", y) &&
getTokenInteger(tokens[4], "width", width) &&
getTokenInteger(tokens[5], "height", height))
{
invalidateTiles(part, x, y, width, height);
}
else
{
Log::error("Unexpected invalidatetiles request: " + tiles);
}
}
}
void TileCache::removeFile(const std::string& fileName)
{
const std::string fullFileName = _cacheDir + "/" + fileName;
if (std::remove(fullFileName.c_str()) == 0)
Log::info("Removed file: " + fullFileName);
}
std::string TileCache::cacheFileName(const TileDesc& tile)
{
std::ostringstream oss;
oss << tile.getPart() << '_' << tile.getWidth() << 'x' << tile.getHeight() << '.'
<< tile.getTilePosX() << ',' << tile.getTilePosY() << '.'
<< tile.getTileWidth() << 'x' << tile.getTileHeight() << ".png";
return oss.str();
}
bool TileCache::parseCacheFileName(const std::string& fileName, int& part, int& width, int& height, int& tilePosX, int& tilePosY, int& tileWidth, int& tileHeight) const
{
return (std::sscanf(fileName.c_str(), "%d_%dx%d.%d,%d.%dx%d.png", &part, &width, &height, &tilePosX, &tilePosY, &tileWidth, &tileHeight) == 7);
}
bool TileCache::intersectsTile(const std::string& fileName, int part, int x, int y, int width, int height) const
{
int tilePart, tilePixelWidth, tilePixelHeight, tilePosX, tilePosY, tileWidth, tileHeight;
if (parseCacheFileName(fileName, tilePart, tilePixelWidth, tilePixelHeight, tilePosX, tilePosY, tileWidth, tileHeight))
{
if (part != -1 && tilePart != part)
return false;
const int left = std::max(x, tilePosX);
const int right = std::min(x + width, tilePosX + tileWidth);
const int top = std::max(y, tilePosY);
const int bottom = std::min(y + height, tilePosY + tileHeight);
if (left <= right && top <= bottom)
return true;
}
return false;
}
Timestamp TileCache::getLastModified()
{
std::fstream modTimeFile(_cacheDir + "/modtime.txt", std::ios::in);
if (!modTimeFile.is_open())
return 0;
Timestamp::TimeVal result;
modTimeFile >> result;
modTimeFile.close();
return result;
}
void TileCache::saveLastModified(const Timestamp& timestamp)
{
std::fstream modTimeFile(_cacheDir + "/modtime.txt", std::ios::out);
modTimeFile << timestamp.raw() << std::endl;
modTimeFile.close();
}
// FIXME: to be further simplified when we centralize tile messages.
void TileCache::subscribeToTileRendering(const TileDesc& tile, const std::shared_ptr<ClientSession> &subscriber)
{
assert(subscriber->getKind() == LOOLSession::Kind::ToClient);
std::unique_lock<std::mutex> lock(_tilesBeingRenderedMutex);
std::shared_ptr<TileBeingRendered> tileBeingRendered = findTileBeingRendered(tile);
std::ostringstream oss;
oss << '(' << tile.getPart() << ',' << tile.getTilePosX() << ',' << tile.getTilePosY() << ')';
const auto name = oss.str();
if (tileBeingRendered)
{
for (const auto &s : tileBeingRendered->_subscribers)
{
if (s.lock().get() == subscriber.get())
{
Log::debug("Redundant request to subscribe on tile " + name);
tileBeingRendered->setVersion(tile.getVersion());
return;
}
}
Log::debug() << "Subscribing to tile " << name << " which has "
<< tileBeingRendered->_subscribers.size()
<< " subscribers already. Adding one more." << Log::end;
tileBeingRendered->_subscribers.push_back(subscriber);
const auto duration = (std::chrono::steady_clock::now() - tileBeingRendered->getStartTime());
if (std::chrono::duration_cast<std::chrono::milliseconds>(duration).count() > COMMAND_TIMEOUT_MS)
{
// Tile painting has stalled. Reissue.
tileBeingRendered->setVersion(tile.getVersion());
}
}
else
{
Log::debug() << "Subscribing to tile " << name << " which has no subscribers. Subscribing for ver: "
<< tile.getVersion() << "." << Log::end;
const std::string cachedName = cacheFileName(tile);
assert(_tilesBeingRendered.find(cachedName) == _tilesBeingRendered.end());
tileBeingRendered = std::make_shared<TileBeingRendered>(cachedName, tile);
tileBeingRendered->_subscribers.push_back(subscriber);
_tilesBeingRendered[cachedName] = tileBeingRendered;
}
}
std::string TileCache::cancelTiles(const std::shared_ptr<ClientSession> &subscriber)
{
assert(subscriber && "cancelTiles expects valid subscriber");
Log::trace("Cancelling tiles for " + subscriber->getName());
std::unique_lock<std::mutex> lock(_tilesBeingRenderedMutex);
const auto sub = subscriber.get();
std::ostringstream oss;
for (auto it = _tilesBeingRendered.begin(); it != _tilesBeingRendered.end(); )
{
if (it->second->getTile().getId() >= 0)
{
// Tile is for a thumbnail, don't cancel it
++it;
continue;
}
auto& subscribers = it->second->_subscribers;
Log::trace("Tile " + it->first + " has " + std::to_string(subscribers.size()) + " subscribers.");
const auto itRem = std::find_if(subscribers.begin(), subscribers.end(),
[sub](std::weak_ptr<ClientSession>& ptr){ return ptr.lock().get() == sub; });
if (itRem != subscribers.end())
{
Log::trace("Tile " + it->first + " has " + std::to_string(subscribers.size()) + " subscribers. Removing one.");
subscribers.erase(itRem, itRem + 1);
if (subscribers.empty())
{
// No other subscriber, remove it from the render queue.
oss << it->second->getVersion() << ',';
it = _tilesBeingRendered.erase(it);
continue;
}
}
++it;
}
const auto canceltiles = oss.str();
return (canceltiles.empty() ? canceltiles : "canceltiles " + canceltiles);
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */