1 //===-- Acceptor.cpp --------------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "Acceptor.h"
11 
12 #include "llvm/ADT/StringRef.h"
13 #include "llvm/Support/ScopedPrinter.h"
14 
15 #include "lldb/Host/ConnectionFileDescriptor.h"
16 #include "lldb/Host/common/TCPSocket.h"
17 #include "lldb/Utility/StreamString.h"
18 #include "lldb/Utility/UriParser.h"
19 
20 using namespace lldb;
21 using namespace lldb_private;
22 using namespace lldb_private::lldb_server;
23 using namespace llvm;
24 
25 namespace {
26 
27 struct SocketScheme {
28   const char *m_scheme;
29   const Socket::SocketProtocol m_protocol;
30 };
31 
32 SocketScheme socket_schemes[] = {
33     {"tcp", Socket::ProtocolTcp},
34     {"udp", Socket::ProtocolUdp},
35     {"unix", Socket::ProtocolUnixDomain},
36     {"unix-abstract", Socket::ProtocolUnixAbstract},
37 };
38 
39 bool FindProtocolByScheme(const char *scheme,
40                           Socket::SocketProtocol &protocol) {
41   for (auto s : socket_schemes) {
42     if (!strcmp(s.m_scheme, scheme)) {
43       protocol = s.m_protocol;
44       return true;
45     }
46   }
47   return false;
48 }
49 
50 const char *FindSchemeByProtocol(const Socket::SocketProtocol protocol) {
51   for (auto s : socket_schemes) {
52     if (s.m_protocol == protocol)
53       return s.m_scheme;
54   }
55   return nullptr;
56 }
57 }
58 
59 Status Acceptor::Listen(int backlog) {
60   return m_listener_socket_up->Listen(StringRef(m_name), backlog);
61 }
62 
63 Status Acceptor::Accept(const bool child_processes_inherit, Connection *&conn) {
64   Socket *conn_socket = nullptr;
65   auto error = m_listener_socket_up->Accept(conn_socket);
66   if (error.Success())
67     conn = new ConnectionFileDescriptor(conn_socket);
68 
69   return error;
70 }
71 
72 Socket::SocketProtocol Acceptor::GetSocketProtocol() const {
73   return m_listener_socket_up->GetSocketProtocol();
74 }
75 
76 const char *Acceptor::GetSocketScheme() const {
77   return FindSchemeByProtocol(GetSocketProtocol());
78 }
79 
80 std::string Acceptor::GetLocalSocketId() const { return m_local_socket_id(); }
81 
82 std::unique_ptr<Acceptor> Acceptor::Create(StringRef name,
83                                            const bool child_processes_inherit,
84                                            Status &error) {
85   error.Clear();
86 
87   Socket::SocketProtocol socket_protocol = Socket::ProtocolUnixDomain;
88   int port;
89   StringRef scheme, host, path;
90   // Try to match socket name as URL - e.g., tcp://localhost:5555
91   if (UriParser::Parse(name, scheme, host, port, path)) {
92     if (!FindProtocolByScheme(scheme.str().c_str(), socket_protocol))
93       error.SetErrorStringWithFormat("Unknown protocol scheme \"%s\"",
94                                      scheme.str().c_str());
95     else
96       name = name.drop_front(scheme.size() + strlen("://"));
97   } else {
98     std::string host_str;
99     std::string port_str;
100     int32_t port = INT32_MIN;
101     // Try to match socket name as $host:port - e.g., localhost:5555
102     if (Socket::DecodeHostAndPort(name, host_str, port_str, port, nullptr))
103       socket_protocol = Socket::ProtocolTcp;
104   }
105 
106   if (error.Fail())
107     return std::unique_ptr<Acceptor>();
108 
109   std::unique_ptr<Socket> listener_socket_up =
110       Socket::Create(socket_protocol, child_processes_inherit, error);
111 
112   LocalSocketIdFunc local_socket_id;
113   if (error.Success()) {
114     if (listener_socket_up->GetSocketProtocol() == Socket::ProtocolTcp) {
115       TCPSocket *tcp_socket =
116           static_cast<TCPSocket *>(listener_socket_up.get());
117       local_socket_id = [tcp_socket]() {
118         auto local_port = tcp_socket->GetLocalPortNumber();
119         return (local_port != 0) ? llvm::to_string(local_port) : "";
120       };
121     } else {
122       const std::string socket_name = name;
123       local_socket_id = [socket_name]() { return socket_name; };
124     }
125 
126     return std::unique_ptr<Acceptor>(
127         new Acceptor(std::move(listener_socket_up), name, local_socket_id));
128   }
129 
130   return std::unique_ptr<Acceptor>();
131 }
132 
133 Acceptor::Acceptor(std::unique_ptr<Socket> &&listener_socket, StringRef name,
134                    const LocalSocketIdFunc &local_socket_id)
135     : m_listener_socket_up(std::move(listener_socket)), m_name(name.str()),
136       m_local_socket_id(local_socket_id) {}
137