1 /*
2 * Copyright (C) 2012-2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <stdlib.h>
18
19 #include <private/android_filesystem_config.h>
20
21 #include "FlushCommand.h"
22 #include "LogBuffer.h"
23 #include "LogBufferElement.h"
24 #include "LogCommand.h"
25 #include "LogReader.h"
26 #include "LogTimes.h"
27 #include "LogUtils.h"
28
FlushCommand(LogReader & reader,bool nonBlock,unsigned long tail,unsigned int logMask,pid_t pid,uint64_t start,uint64_t timeout)29 FlushCommand::FlushCommand(LogReader &reader,
30 bool nonBlock,
31 unsigned long tail,
32 unsigned int logMask,
33 pid_t pid,
34 uint64_t start,
35 uint64_t timeout) :
36 mReader(reader),
37 mNonBlock(nonBlock),
38 mTail(tail),
39 mLogMask(logMask),
40 mPid(pid),
41 mStart(start),
42 mTimeout((start > 1) ? timeout : 0) {
43 }
44
45 // runSocketCommand is called once for every open client on the
46 // log reader socket. Here we manage and associated the reader
47 // client tracking and log region locks LastLogTimes list of
48 // LogTimeEntrys, and spawn a transitory per-client thread to
49 // work at filing data to the socket.
50 //
51 // global LogTimeEntry::lock() is used to protect access,
52 // reference counts are used to ensure that individual
53 // LogTimeEntry lifetime is managed when not protected.
runSocketCommand(SocketClient * client)54 void FlushCommand::runSocketCommand(SocketClient *client) {
55 LogTimeEntry *entry = NULL;
56 LastLogTimes × = mReader.logbuf().mTimes;
57
58 LogTimeEntry::lock();
59 LastLogTimes::iterator it = times.begin();
60 while(it != times.end()) {
61 entry = (*it);
62 if (entry->mClient == client) {
63 if (entry->mTimeout.tv_sec || entry->mTimeout.tv_nsec) {
64 LogTimeEntry::unlock();
65 return;
66 }
67 entry->triggerReader_Locked();
68 if (entry->runningReader_Locked()) {
69 LogTimeEntry::unlock();
70 return;
71 }
72 entry->incRef_Locked();
73 break;
74 }
75 it++;
76 }
77
78 if (it == times.end()) {
79 // Create LogTimeEntry in notifyNewLog() ?
80 if (mTail == (unsigned long) -1) {
81 LogTimeEntry::unlock();
82 return;
83 }
84 entry = new LogTimeEntry(mReader, client, mNonBlock, mTail, mLogMask,
85 mPid, mStart, mTimeout);
86 times.push_front(entry);
87 }
88
89 client->incRef();
90
91 // release client and entry reference counts once done
92 entry->startReader_Locked();
93 LogTimeEntry::unlock();
94 }
95
hasReadLogs(SocketClient * client)96 bool FlushCommand::hasReadLogs(SocketClient *client) {
97 return clientHasLogCredentials(client);
98 }
99
clientHasSecurityCredentials(SocketClient * client)100 static bool clientHasSecurityCredentials(SocketClient *client) {
101 return (client->getUid() == AID_SYSTEM) || (client->getGid() == AID_SYSTEM);
102 }
103
hasSecurityLogs(SocketClient * client)104 bool FlushCommand::hasSecurityLogs(SocketClient *client) {
105 return clientHasSecurityCredentials(client);
106 }
107