1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
|
// client.h
/**
* Copyright (C) 2008 10gen Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/* Client represents a connection to the database (the server-side) and corresponds
to an open socket (or logical connection if pooling on sockets) from a client.
todo: switch to asio...this will fit nicely with that.
*/
#pragma once
#include "../pch.h"
#include "security.h"
#include "namespace-inl.h"
#include "lasterror.h"
#include "stats/top.h"
namespace mongo {
extern class ReplSet *theReplSet;
class AuthenticationInfo;
class Database;
class CurOp;
class Command;
class Client;
class AbstractMessagingPort;
extern boost::thread_specific_ptr<Client> currentClient;
typedef long long ConnectionId;
/** the database's concept of an outside "client" */
class Client : boost::noncopyable {
public:
class Context;
static mongo::mutex clientsMutex;
static set<Client*> clients; // always be in clientsMutex when manipulating this
static int recommendedYieldMicros( int * writers = 0 , int * readers = 0 );
static int getActiveClientCount( int& writers , int& readers );
static Client *syncThread;
/* each thread which does db operations has a Client object in TLS.
call this when your thread starts.
*/
static Client& initThread(const char *desc, AbstractMessagingPort *mp = 0);
~Client();
/*
this has to be called as the client goes away, but before thread termination
@return true if anything was done
*/
bool shutdown();
/** set so isSyncThread() works */
void iAmSyncThread() {
wassert( syncThread == 0 );
syncThread = this;
}
/** @return true if this client is the replication secondary pull thread. not used much, is used in create index sync code. */
bool isSyncThread() const { return this == syncThread; }
string clientAddress(bool includePort=false) const;
const AuthenticationInfo * getAuthenticationInfo() const { return &_ai; }
AuthenticationInfo * getAuthenticationInfo() { return &_ai; }
bool isAdmin() { return _ai.isAuthorized( "admin" ); }
CurOp* curop() const { return _curOp; }
Context* getContext() const { return _context; }
Database* database() const { return _context ? _context->db() : 0; }
const char *ns() const { return _context->ns(); }
const char *desc() const { return _desc; }
void setLastOp( ReplTime op ) { _lastOp = op; }
ReplTime getLastOp() const { return _lastOp; }
/* report what the last operation was. used by getlasterror */
void appendLastOp( BSONObjBuilder& b ) const;
bool isGod() const { return _god; } /* this is for map/reduce writes */
string toString() const;
void gotHandshake( const BSONObj& o );
BSONObj getRemoteID() const { return _remoteId; }
BSONObj getHandshake() const { return _handshake; }
AbstractMessagingPort * port() const { return _mp; }
ConnectionId getConnectionId() const { return _connectionId; }
private:
ConnectionId _connectionId; // > 0 for things "conn", 0 otherwise
string _threadId; // "" on non support systems
CurOp * _curOp;
Context * _context;
bool _shutdown;
const char *_desc;
bool _god;
AuthenticationInfo _ai;
ReplTime _lastOp;
BSONObj _handshake;
BSONObj _remoteId;
AbstractMessagingPort * const _mp;
Client(const char *desc, AbstractMessagingPort *p = 0);
friend class CurOp;
public:
/* set _god=true temporarily, safely */
class GodScope {
bool _prev;
public:
GodScope();
~GodScope();
};
/* Set database we want to use, then, restores when we finish (are out of scope)
Note this is also helpful if an exception happens as the state if fixed up.
*/
class Context : boost::noncopyable {
public:
/**
* this is the main constructor
* use this unless there is a good reason not to
*/
Context(const string& ns, string path=dbpath, mongolock * lock = 0 , bool doauth=true );
/* this version saves the context but doesn't yet set the new one: */
Context();
/**
* if you are doing this after allowing a write there could be a race condition
* if someone closes that db. this checks that the DB is still valid
*/
Context( string ns , Database * db, bool doauth=true );
~Context();
Client* getClient() const { return _client; }
Database* db() const { return _db; }
const char * ns() const { return _ns.c_str(); }
/** @return if the db was created by this Context */
bool justCreated() const { return _justCreated; }
bool equals( const string& ns , const string& path=dbpath ) const { return _ns == ns && _path == path; }
/**
* @return true iff the current Context is using db/path
*/
bool inDB( const string& db , const string& path=dbpath ) const;
void clear() { _ns = ""; _db = 0; }
/**
* call before unlocking, so clear any non-thread safe state
*/
void unlocked() { _db = 0; }
/**
* call after going back into the lock, will re-establish non-thread safe stuff
*/
void relocked() { _finishInit(); }
friend class CurOp;
private:
/**
* at this point _client, _oldContext and _ns have to be set
* _db should not have been touched
* this will set _db and create if needed
* will also set _client->_context to this
*/
void _finishInit( bool doauth=true);
void _auth( int lockState = dbMutex.getState() );
Client * _client;
Context * _oldContext;
string _path;
mongolock * _lock;
bool _justCreated;
string _ns;
Database * _db;
}; // class Client::Context
};
/** get the Client object for this thread. */
inline Client& cc() {
Client * c = currentClient.get();
assert( c );
return *c;
}
inline Client::GodScope::GodScope() {
_prev = cc()._god;
cc()._god = true;
}
inline Client::GodScope::~GodScope() { cc()._god = _prev; }
/* this unlocks, does NOT upgrade. that works for our current usage */
inline void mongolock::releaseAndWriteLock() {
if( !_writelock ) {
#if BOOST_VERSION >= 103500
int s = dbMutex.getState();
if( s != -1 ) {
log() << "error: releaseAndWriteLock() s == " << s << endl;
msgasserted( 12600, "releaseAndWriteLock: unlock_shared failed, probably recursive" );
}
#endif
_writelock = true;
dbMutex.unlock_shared();
dbMutex.lock();
if ( cc().getContext() )
cc().getContext()->unlocked();
}
}
string sayClientState();
inline bool haveClient() { return currentClient.get() > 0; }
};
|
