1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "shell_protocol.h"
18 
19 #include <gtest/gtest.h>
20 
21 #include <signal.h>
22 #include <string.h>
23 
24 #include "sysdeps.h"
25 
26 class ShellProtocolTest : public ::testing::Test {
27   public:
28     static void SetUpTestCase() {
29 #if !defined(_WIN32)
30         // This is normally done in main.cpp.
31         saved_sigpipe_handler_ = signal(SIGPIPE, SIG_IGN);
32 #endif
33     }
34 
35     static void TearDownTestCase() {
36 #if !defined(_WIN32)
37         signal(SIGPIPE, saved_sigpipe_handler_);
38 #endif
39     }
40 
41     // Initializes the socketpair and ShellProtocols needed for testing.
42     void SetUp() {
43         int fds[2];
44         ASSERT_EQ(0, adb_socketpair(fds));
45         read_fd_ = fds[0];
46         write_fd_ = fds[1];
47 
48         write_protocol_ = new ShellProtocol(write_fd_);
49         ASSERT_TRUE(write_protocol_ != nullptr);
50 
51         read_protocol_ = new ShellProtocol(read_fd_);
52         ASSERT_TRUE(read_protocol_ != nullptr);
53     }
54 
55     // Cleans up FDs and ShellProtocols. If an FD is closed manually during a
56     // test, set it to -1 to prevent TearDown() trying to close it again.
57     void TearDown() {
58         for (int fd : {read_fd_, write_fd_}) {
59             if (fd >= 0) {
60                 adb_close(fd);
61             }
62         }
63         for (ShellProtocol* protocol : {read_protocol_, write_protocol_}) {
64             if (protocol) {
65                 delete protocol;
66             }
67         }
68     }
69 
70     // Fakes the buffer size so we can test filling buffers.
71     void SetReadDataCapacity(size_t size) {
72         read_protocol_->buffer_end_ = read_protocol_->data() + size;
73     }
74 
75 #if !defined(_WIN32)
76     static sig_t saved_sigpipe_handler_;
77 #endif
78 
79     int read_fd_ = -1, write_fd_ = -1;
80     ShellProtocol *read_protocol_ = nullptr, *write_protocol_ = nullptr;
81 };
82 
83 #if !defined(_WIN32)
84 sig_t ShellProtocolTest::saved_sigpipe_handler_ = nullptr;
85 #endif
86 
87 namespace {
88 
89 // Returns true if the packet contains the given values. `data` can't be null.
90 bool PacketEquals(const ShellProtocol* protocol, ShellProtocol::Id id,
91                     const void* data, size_t data_length) {
92     // Note that passing memcmp null is bad, even if data_length is 0.
93     return (protocol->id() == id &&
94             protocol->data_length() == data_length &&
95             !memcmp(data, protocol->data(), data_length));
96 }
97 
98 }  // namespace
99 
100 // Tests data that can fit in a single packet.
101 TEST_F(ShellProtocolTest, FullPacket) {
102     ShellProtocol::Id id = ShellProtocol::kIdStdout;
103     char data[] = "abc 123 \0\r\n";
104 
105     memcpy(write_protocol_->data(), data, sizeof(data));
106     ASSERT_TRUE(write_protocol_->Write(id, sizeof(data)));
107 
108     ASSERT_TRUE(read_protocol_->Read());
109     ASSERT_TRUE(PacketEquals(read_protocol_, id, data, sizeof(data)));
110 }
111 
112 // Tests data that has to be read multiple times due to smaller read buffer.
113 TEST_F(ShellProtocolTest, ReadBufferOverflow) {
114     ShellProtocol::Id id = ShellProtocol::kIdStdin;
115 
116     memcpy(write_protocol_->data(), "1234567890", 10);
117     ASSERT_TRUE(write_protocol_->Write(id, 10));
118 
119     SetReadDataCapacity(4);
120     ASSERT_TRUE(read_protocol_->Read());
121     ASSERT_TRUE(PacketEquals(read_protocol_, id, "1234", 4));
122     ASSERT_TRUE(read_protocol_->Read());
123     ASSERT_TRUE(PacketEquals(read_protocol_, id, "5678", 4));
124     ASSERT_TRUE(read_protocol_->Read());
125     ASSERT_TRUE(PacketEquals(read_protocol_, id, "90", 2));
126 }
127 
128 // Tests a zero length packet.
129 TEST_F(ShellProtocolTest, ZeroLengthPacket) {
130     ShellProtocol::Id id = ShellProtocol::kIdStderr;
131 
132     ASSERT_TRUE(write_protocol_->Write(id, 0));
133     ASSERT_TRUE(read_protocol_->Read());
134     char buf[1];
135     ASSERT_TRUE(PacketEquals(read_protocol_, id, buf, 0));
136 }
137 
138 // Tests exit code packets.
139 TEST_F(ShellProtocolTest, ExitCodePacket) {
140     write_protocol_->data()[0] = 20;
141     ASSERT_TRUE(write_protocol_->Write(ShellProtocol::kIdExit, 1));
142 
143     ASSERT_TRUE(read_protocol_->Read());
144     ASSERT_EQ(ShellProtocol::kIdExit, read_protocol_->id());
145     ASSERT_EQ(20, read_protocol_->data()[0]);
146 }
147 
148 // Tests writing to a closed pipe.
149 TEST_F(ShellProtocolTest, WriteToClosedPipeFail) {
150     adb_close(read_fd_);
151     read_fd_ = -1;
152 
153     ASSERT_FALSE(write_protocol_->Write(ShellProtocol::kIdStdout, 0));
154 }
155 
156 // Tests writing to a closed FD.
157 TEST_F(ShellProtocolTest, WriteToClosedFdFail) {
158     adb_close(write_fd_);
159     write_fd_ = -1;
160 
161     ASSERT_FALSE(write_protocol_->Write(ShellProtocol::kIdStdout, 0));
162 }
163 
164 // Tests reading from a closed pipe.
165 TEST_F(ShellProtocolTest, ReadFromClosedPipeFail) {
166     adb_close(write_fd_);
167     write_fd_ = -1;
168 
169     ASSERT_FALSE(read_protocol_->Read());
170 }
171 
172 // Tests reading from a closed FD.
173 TEST_F(ShellProtocolTest, ReadFromClosedFdFail) {
174     adb_close(read_fd_);
175     read_fd_ = -1;
176 
177     ASSERT_FALSE(read_protocol_->Read());
178 }
179 
180 // Tests reading from a closed pipe that has a packet waiting. This checks that
181 // even if the pipe closes before we can fully read its contents we will still
182 // be able to access the last packets.
183 TEST_F(ShellProtocolTest, ReadPacketFromClosedPipe) {
184     ShellProtocol::Id id = ShellProtocol::kIdStdout;
185     char data[] = "foo bar";
186 
187     memcpy(write_protocol_->data(), data, sizeof(data));
188     ASSERT_TRUE(write_protocol_->Write(id, sizeof(data)));
189     adb_close(write_fd_);
190     write_fd_ = -1;
191 
192     // First read should grab the packet.
193     ASSERT_TRUE(read_protocol_->Read());
194     ASSERT_TRUE(PacketEquals(read_protocol_, id, data, sizeof(data)));
195 
196     // Second read should fail.
197     ASSERT_FALSE(read_protocol_->Read());
198 }
199