Bitcoin Core  27.99.0
P2P Digital Currency
sock.h
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1 // Copyright (c) 2020-2022 The Bitcoin Core developers
2 // Distributed under the MIT software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4 
5 #ifndef BITCOIN_UTIL_SOCK_H
6 #define BITCOIN_UTIL_SOCK_H
7 
8 #include <compat/compat.h>
9 #include <util/threadinterrupt.h>
10 #include <util/time.h>
11 
12 #include <chrono>
13 #include <memory>
14 #include <string>
15 #include <unordered_map>
16 
21 static constexpr auto MAX_WAIT_FOR_IO = 1s;
22 
26 class Sock
27 {
28 public:
29  Sock() = delete;
30 
34  explicit Sock(SOCKET s);
35 
39  Sock(const Sock&) = delete;
40 
44  Sock(Sock&& other);
45 
49  virtual ~Sock();
50 
54  Sock& operator=(const Sock&) = delete;
55 
59  virtual Sock& operator=(Sock&& other);
60 
65  [[nodiscard]] virtual ssize_t Send(const void* data, size_t len, int flags) const;
66 
71  [[nodiscard]] virtual ssize_t Recv(void* buf, size_t len, int flags) const;
72 
77  [[nodiscard]] virtual int Connect(const sockaddr* addr, socklen_t addr_len) const;
78 
83  [[nodiscard]] virtual int Bind(const sockaddr* addr, socklen_t addr_len) const;
84 
89  [[nodiscard]] virtual int Listen(int backlog) const;
90 
97  [[nodiscard]] virtual std::unique_ptr<Sock> Accept(sockaddr* addr, socklen_t* addr_len) const;
98 
104  [[nodiscard]] virtual int GetSockOpt(int level,
105  int opt_name,
106  void* opt_val,
107  socklen_t* opt_len) const;
108 
114  [[nodiscard]] virtual int SetSockOpt(int level,
115  int opt_name,
116  const void* opt_val,
117  socklen_t opt_len) const;
118 
124  [[nodiscard]] virtual int GetSockName(sockaddr* name, socklen_t* name_len) const;
125 
130  [[nodiscard]] virtual bool SetNonBlocking() const;
131 
136  [[nodiscard]] virtual bool IsSelectable() const;
137 
138  using Event = uint8_t;
139 
143  static constexpr Event RECV = 0b001;
144 
148  static constexpr Event SEND = 0b010;
149 
154  static constexpr Event ERR = 0b100;
155 
166  [[nodiscard]] virtual bool Wait(std::chrono::milliseconds timeout,
167  Event requested,
168  Event* occurred = nullptr) const;
169 
173  struct Events {
174  explicit Events(Event req) : requested{req} {}
177  };
178 
180  size_t operator()(const std::shared_ptr<const Sock>& s) const
181  {
182  return s ? s->m_socket : std::numeric_limits<SOCKET>::max();
183  }
184  };
185 
187  bool operator()(const std::shared_ptr<const Sock>& lhs,
188  const std::shared_ptr<const Sock>& rhs) const
189  {
190  if (lhs && rhs) {
191  return lhs->m_socket == rhs->m_socket;
192  }
193  if (!lhs && !rhs) {
194  return true;
195  }
196  return false;
197  }
198  };
199 
208  using EventsPerSock = std::unordered_map<std::shared_ptr<const Sock>, Events, HashSharedPtrSock, EqualSharedPtrSock>;
209 
218  [[nodiscard]] virtual bool WaitMany(std::chrono::milliseconds timeout,
219  EventsPerSock& events_per_sock) const;
220 
221  /* Higher level, convenience, methods. These may throw. */
222 
231  virtual void SendComplete(Span<const unsigned char> data,
232  std::chrono::milliseconds timeout,
233  CThreadInterrupt& interrupt) const;
234 
238  virtual void SendComplete(Span<const char> data,
239  std::chrono::milliseconds timeout,
240  CThreadInterrupt& interrupt) const;
241 
254  [[nodiscard]] virtual std::string RecvUntilTerminator(uint8_t terminator,
255  std::chrono::milliseconds timeout,
256  CThreadInterrupt& interrupt,
257  size_t max_data) const;
258 
264  [[nodiscard]] virtual bool IsConnected(std::string& errmsg) const;
265 
269  bool operator==(SOCKET s) const;
270 
271 protected:
276 
277 private:
281  void Close();
282 };
283 
285 std::string NetworkErrorString(int err);
286 
287 #endif // BITCOIN_UTIL_SOCK_H
int flags
Definition: bitcoin-tx.cpp:528
A helper class for interruptible sleeps.
RAII helper class that manages a socket and closes it automatically when it goes out of scope.
Definition: sock.h:27
virtual std::unique_ptr< Sock > Accept(sockaddr *addr, socklen_t *addr_len) const
accept(2) wrapper.
Definition: sock.cpp:70
virtual ssize_t Send(const void *data, size_t len, int flags) const
send(2) wrapper.
Definition: sock.cpp:45
static constexpr Event SEND
If passed to Wait(), then it will wait for readiness to send to the socket.
Definition: sock.h:148
SOCKET m_socket
Contained socket.
Definition: sock.h:275
virtual int Bind(const sockaddr *addr, socklen_t addr_len) const
bind(2) wrapper.
Definition: sock.cpp:60
virtual void SendComplete(Span< const unsigned char > data, std::chrono::milliseconds timeout, CThreadInterrupt &interrupt) const
Send the given data, retrying on transient errors.
Definition: sock.cpp:245
virtual bool Wait(std::chrono::milliseconds timeout, Event requested, Event *occurred=nullptr) const
Wait for readiness for input (recv) or output (send).
Definition: sock.cpp:139
virtual ~Sock()
Destructor, close the socket or do nothing if empty.
Definition: sock.cpp:35
uint8_t Event
Definition: sock.h:138
Sock(const Sock &)=delete
Copy constructor, disabled because closing the same socket twice is undesirable.
virtual int GetSockName(sockaddr *name, socklen_t *name_len) const
getsockname(2) wrapper.
Definition: sock.cpp:106
void Close()
Close m_socket if it is not INVALID_SOCKET.
Definition: sock.cpp:401
virtual bool WaitMany(std::chrono::milliseconds timeout, EventsPerSock &events_per_sock) const
Same as Wait(), but wait on many sockets within the same timeout.
Definition: sock.cpp:159
static constexpr Event ERR
Ignored if passed to Wait(), but could be set in the occurred events if an exceptional condition has ...
Definition: sock.h:154
virtual bool IsConnected(std::string &errmsg) const
Check if still connected.
Definition: sock.cpp:376
virtual int SetSockOpt(int level, int opt_name, const void *opt_val, socklen_t opt_len) const
setsockopt(2) wrapper.
Definition: sock.cpp:101
static constexpr Event RECV
If passed to Wait(), then it will wait for readiness to read from the socket.
Definition: sock.h:143
virtual int GetSockOpt(int level, int opt_name, void *opt_val, socklen_t *opt_len) const
getsockopt(2) wrapper.
Definition: sock.cpp:96
virtual int Connect(const sockaddr *addr, socklen_t addr_len) const
connect(2) wrapper.
Definition: sock.cpp:55
Sock & operator=(const Sock &)=delete
Copy assignment operator, disabled because closing the same socket twice is undesirable.
virtual ssize_t Recv(void *buf, size_t len, int flags) const
recv(2) wrapper.
Definition: sock.cpp:50
Sock()=delete
virtual std::string RecvUntilTerminator(uint8_t terminator, std::chrono::milliseconds timeout, CThreadInterrupt &interrupt, size_t max_data) const
Read from socket until a terminator character is encountered.
Definition: sock.cpp:293
virtual int Listen(int backlog) const
listen(2) wrapper.
Definition: sock.cpp:65
virtual bool SetNonBlocking() const
Set the non-blocking option on the socket.
Definition: sock.cpp:111
std::unordered_map< std::shared_ptr< const Sock >, Events, HashSharedPtrSock, EqualSharedPtrSock > EventsPerSock
On which socket to wait for what events in WaitMany().
Definition: sock.h:208
virtual bool IsSelectable() const
Check if the underlying socket can be used for select(2) (or the Wait() method).
Definition: sock.cpp:130
bool operator==(SOCKET s) const
Check if the internal socket is equal to s.
Definition: sock.cpp:417
unsigned int SOCKET
Definition: compat.h:46
const char * name
Definition: rest.cpp:48
static constexpr auto MAX_WAIT_FOR_IO
Maximum time to wait for I/O readiness.
Definition: sock.h:21
std::string NetworkErrorString(int err)
Return readable error string for a network error code.
Definition: sock.cpp:422
bool operator()(const std::shared_ptr< const Sock > &lhs, const std::shared_ptr< const Sock > &rhs) const
Definition: sock.h:187
Auxiliary requested/occurred events to wait for in WaitMany().
Definition: sock.h:173
Event requested
Definition: sock.h:175
Events(Event req)
Definition: sock.h:174
Event occurred
Definition: sock.h:176
size_t operator()(const std::shared_ptr< const Sock > &s) const
Definition: sock.h:180