platform_system_core/logd/FlushCommand.cpp

88 lines
2.7 KiB
C++

/*
* Copyright (C) 2012-2014 The Android Open Source Project
*
* Licensed 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
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdlib.h>
#include "FlushCommand.h"
#include "LogBufferElement.h"
#include "LogCommand.h"
#include "LogReader.h"
#include "LogTimes.h"
FlushCommand::FlushCommand(LogReader &reader,
bool nonBlock,
unsigned long tail,
unsigned int logMask,
pid_t pid,
uint64_t start) :
mReader(reader),
mNonBlock(nonBlock),
mTail(tail),
mLogMask(logMask),
mPid(pid),
mStart(start) {
}
// runSocketCommand is called once for every open client on the
// log reader socket. Here we manage and associated the reader
// client tracking and log region locks LastLogTimes list of
// LogTimeEntrys, and spawn a transitory per-client thread to
// work at filing data to the socket.
//
// global LogTimeEntry::lock() is used to protect access,
// reference counts are used to ensure that individual
// LogTimeEntry lifetime is managed when not protected.
void FlushCommand::runSocketCommand(SocketClient *client) {
LogTimeEntry *entry = NULL;
LastLogTimes &times = mReader.logbuf().mTimes;
LogTimeEntry::lock();
LastLogTimes::iterator it = times.begin();
while(it != times.end()) {
entry = (*it);
if (entry->mClient == client) {
entry->triggerReader_Locked();
if (entry->runningReader_Locked()) {
LogTimeEntry::unlock();
return;
}
entry->incRef_Locked();
break;
}
it++;
}
if (it == times.end()) {
// Create LogTimeEntry in notifyNewLog() ?
if (mTail == (unsigned long) -1) {
LogTimeEntry::unlock();
return;
}
entry = new LogTimeEntry(mReader, client, mNonBlock, mTail, mLogMask, mPid, mStart);
times.push_front(entry);
}
client->incRef();
// release client and entry reference counts once done
entry->startReader_Locked();
LogTimeEntry::unlock();
}
bool FlushCommand::hasReadLogs(SocketClient *client) {
return clientHasLogCredentials(client);
}