1 //===-- CommunicationTest.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/Core/Communication.h"
10 #include "lldb/Host/Config.h"
11 #include "lldb/Host/ConnectionFileDescriptor.h"
12 #include "lldb/Host/Pipe.h"
13 #include "llvm/Testing/Support/Error.h"
14 #include "gtest/gtest.h"
15 
16 #include <thread>
17 
18 #if LLDB_ENABLE_POSIX
19 #include <fcntl.h>
20 #endif
21 
22 using namespace lldb_private;
23 
24 #ifndef _WIN32
25 TEST(CommunicationTest, SynchronizeWhileClosing) {
26   // Set up a communication object reading from a pipe.
27   Pipe pipe;
28   ASSERT_THAT_ERROR(pipe.CreateNew(/*child_process_inherit=*/false).ToError(),
29                     llvm::Succeeded());
30 
31   Communication comm("test");
32   comm.SetConnection(std::make_unique<ConnectionFileDescriptor>(
33       pipe.ReleaseReadFileDescriptor(), /*owns_fd=*/true));
34   comm.SetCloseOnEOF(true);
35   ASSERT_TRUE(comm.StartReadThread());
36 
37   // Ensure that we can safely synchronize with the read thread while it is
38   // closing the read end (in response to us closing the write end).
39   pipe.CloseWriteFileDescriptor();
40   comm.SynchronizeWithReadThread();
41 
42   ASSERT_TRUE(comm.StopReadThread());
43 }
44 #endif
45 
46 #if LLDB_ENABLE_POSIX
47 TEST(CommunicationTest, WriteAll) {
48   Pipe pipe;
49   ASSERT_THAT_ERROR(pipe.CreateNew(/*child_process_inherit=*/false).ToError(),
50                     llvm::Succeeded());
51 
52   // Make the write end non-blocking in order to easily reproduce a partial
53   // write.
54   int write_fd = pipe.ReleaseWriteFileDescriptor();
55   int flags = fcntl(write_fd, F_GETFL);
56   ASSERT_NE(flags, -1);
57   ASSERT_NE(fcntl(write_fd, F_SETFL, flags | O_NONBLOCK), -1);
58 
59   ConnectionFileDescriptor read_conn{pipe.ReleaseReadFileDescriptor(),
60                                      /*owns_fd=*/true};
61   Communication write_comm("test");
62   write_comm.SetConnection(
63       std::make_unique<ConnectionFileDescriptor>(write_fd, /*owns_fd=*/true));
64 
65   std::thread read_thread{[&read_conn]() {
66     // Read using a smaller buffer to increase chances of partial write.
67     char buf[128 * 1024];
68     lldb::ConnectionStatus conn_status;
69 
70     do {
71       read_conn.Read(buf, sizeof(buf), std::chrono::seconds(1), conn_status,
72                      nullptr);
73     } while (conn_status != lldb::eConnectionStatusEndOfFile);
74   }};
75 
76   // Write 1 MiB of data into the pipe.
77   lldb::ConnectionStatus conn_status;
78   Status error;
79   std::vector<uint8_t> data(1024 * 1024, 0x80);
80   EXPECT_EQ(write_comm.WriteAll(data.data(), data.size(), conn_status, &error),
81             data.size());
82   EXPECT_EQ(conn_status, lldb::eConnectionStatusSuccess);
83   EXPECT_FALSE(error.Fail());
84 
85   // Close the write end in order to trigger EOF.
86   write_comm.Disconnect();
87   read_thread.join();
88 }
89 #endif
90