Bug Summary

File:build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/lldb/source/Host/common/UDPSocket.cpp
Warning:line 126, column 3
Value stored to 'err' is never read

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name UDPSocket.cpp -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/build-llvm/tools/clang/stage2-bins -resource-dir /usr/lib/llvm-16/lib/clang/16.0.0 -isystem /usr/include/libxml2 -D HAVE_ROUND -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I tools/lldb/source/Host -I /build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/lldb/source/Host -I /build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/lldb/include -I tools/lldb/include -I include -I /build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/llvm/include -I /usr/include/python3.9 -I /build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/clang/include -I tools/lldb/../clang/include -I /build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/lldb/source -I tools/lldb/source -D _FORTIFY_SOURCE=2 -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-16/lib/clang/16.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fmacro-prefix-map=/build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/= -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/= -O2 -Wno-unused-command-line-argument -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -Wno-misleading-indentation -Wno-deprecated-declarations -Wno-unknown-pragmas -Wno-strict-aliasing -Wno-stringop-truncation -std=c++17 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/build-llvm/tools/clang/stage2-bins -fdebug-prefix-map=/build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fdebug-prefix-map=/build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/= -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2022-09-29-125212-15910-1 -x c++ /build/llvm-toolchain-snapshot-16~++20220929111209+ac2e2d659819/lldb/source/Host/common/UDPSocket.cpp
1//===-- UDPSocket.cpp -----------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "lldb/Host/common/UDPSocket.h"
10
11#include "lldb/Host/Config.h"
12#include "lldb/Utility/LLDBLog.h"
13#include "lldb/Utility/Log.h"
14
15#if LLDB_ENABLE_POSIX1
16#include <arpa/inet.h>
17#include <sys/socket.h>
18#endif
19
20#include <memory>
21
22using namespace lldb;
23using namespace lldb_private;
24
25static const int kDomain = AF_INET2;
26static const int kType = SOCK_DGRAMSOCK_DGRAM;
27
28static const char *g_not_supported_error = "Not supported";
29
30UDPSocket::UDPSocket(NativeSocket socket) : Socket(ProtocolUdp, true, true) {
31 m_socket = socket;
32}
33
34UDPSocket::UDPSocket(bool should_close, bool child_processes_inherit)
35 : Socket(ProtocolUdp, should_close, child_processes_inherit) {}
36
37size_t UDPSocket::Send(const void *buf, const size_t num_bytes) {
38 return ::sendto(m_socket, static_cast<const char *>(buf), num_bytes, 0,
39 m_sockaddr, m_sockaddr.GetLength());
40}
41
42Status UDPSocket::Connect(llvm::StringRef name) {
43 return Status("%s", g_not_supported_error);
44}
45
46Status UDPSocket::Listen(llvm::StringRef name, int backlog) {
47 return Status("%s", g_not_supported_error);
48}
49
50Status UDPSocket::Accept(Socket *&socket) {
51 return Status("%s", g_not_supported_error);
52}
53
54llvm::Expected<std::unique_ptr<UDPSocket>>
55UDPSocket::Connect(llvm::StringRef name, bool child_processes_inherit) {
56 std::unique_ptr<UDPSocket> socket;
57
58 Log *log = GetLog(LLDBLog::Connection);
59 LLDB_LOG(log, "host/port = {0}", name)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("lldb/source/Host/common/UDPSocket.cpp"
, __func__, "host/port = {0}", name); } while (0)
;
60
61 Status error;
62 llvm::Expected<HostAndPort> host_port = DecodeHostAndPort(name);
63 if (!host_port)
64 return host_port.takeError();
65
66 // At this point we have setup the receive port, now we need to setup the UDP
67 // send socket
68
69 struct addrinfo hints;
70 struct addrinfo *service_info_list = nullptr;
71
72 ::memset(&hints, 0, sizeof(hints));
73 hints.ai_family = kDomain;
74 hints.ai_socktype = kType;
75 int err = ::getaddrinfo(host_port->hostname.c_str(), std::to_string(host_port->port).c_str(), &hints,
76 &service_info_list);
77 if (err != 0) {
78 error.SetErrorStringWithFormat(
79#if defined(_WIN32) && defined(UNICODE)
80 "getaddrinfo(%s, %d, &hints, &info) returned error %i (%S)",
81#else
82 "getaddrinfo(%s, %d, &hints, &info) returned error %i (%s)",
83#endif
84 host_port->hostname.c_str(), host_port->port, err, gai_strerror(err));
85 return error.ToError();
86 }
87
88 for (struct addrinfo *service_info_ptr = service_info_list;
89 service_info_ptr != nullptr;
90 service_info_ptr = service_info_ptr->ai_next) {
91 auto send_fd = CreateSocket(
92 service_info_ptr->ai_family, service_info_ptr->ai_socktype,
93 service_info_ptr->ai_protocol, child_processes_inherit, error);
94 if (error.Success()) {
95 socket.reset(new UDPSocket(send_fd));
96 socket->m_sockaddr = service_info_ptr;
97 break;
98 } else
99 continue;
100 }
101
102 ::freeaddrinfo(service_info_list);
103
104 if (!socket)
105 return error.ToError();
106
107 SocketAddress bind_addr;
108
109 // Only bind to the loopback address if we are expecting a connection from
110 // localhost to avoid any firewall issues.
111 const bool bind_addr_success = (host_port->hostname == "127.0.0.1" || host_port->hostname == "localhost")
112 ? bind_addr.SetToLocalhost(kDomain, host_port->port)
113 : bind_addr.SetToAnyAddress(kDomain, host_port->port);
114
115 if (!bind_addr_success) {
116 error.SetErrorString("Failed to get hostspec to bind for");
117 return error.ToError();
118 }
119
120 bind_addr.SetPort(0); // Let the source port # be determined dynamically
121
122 err = ::bind(socket->GetNativeSocket(), bind_addr, bind_addr.GetLength());
123
124 struct sockaddr_in source_info;
125 socklen_t address_len = sizeof (struct sockaddr_in);
126 err = ::getsockname(socket->GetNativeSocket(),
Value stored to 'err' is never read
127 (struct sockaddr *)&source_info, &address_len);
128
129 return std::move(socket);
130}
131
132std::string UDPSocket::GetRemoteConnectionURI() const {
133 if (m_socket != kInvalidSocketValue) {
134 return std::string(llvm::formatv(
135 "udp://[{0}]:{1}", m_sockaddr.GetIPAddress(), m_sockaddr.GetPort()));
136 }
137 return "";
138}