1 /*
2  * Copyright (C) 2017 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 "perfetto/base/scoped_file.h"
18 
19 #include <fcntl.h>
20 #include <unistd.h>
21 
22 #include "gtest/gtest.h"
23 
24 namespace perfetto {
25 namespace base {
26 namespace {
27 
28 TEST(ScopedDirTest, CloseOutOfScope) {
29   DIR* dir_handle = opendir(".");
30   ASSERT_NE(nullptr, dir_handle);
31   int dir_handle_fd = dirfd(dir_handle);
32   ASSERT_GE(dir_handle_fd, 0);
33   {
34     ScopedDir scoped_dir(dir_handle);
35     ASSERT_EQ(dir_handle, scoped_dir.get());
36     ASSERT_TRUE(scoped_dir);
37   }
38   ASSERT_NE(0, close(dir_handle_fd));  // Should fail when closing twice.
39 }
40 
41 TEST(ScopedFileTest, CloseOutOfScope) {
42   int raw_fd = open("/dev/null", O_RDONLY);
43   ASSERT_GE(raw_fd, 0);
44   {
45     ScopedFile scoped_file(raw_fd);
46     ASSERT_EQ(raw_fd, scoped_file.get());
47     ASSERT_EQ(raw_fd, *scoped_file);
48     ASSERT_TRUE(scoped_file);
49   }
50   ASSERT_NE(0, close(raw_fd));  // Should fail when closing twice.
51 }
52 
53 TEST(ScopedFstreamTest, CloseOutOfScope) {
54   FILE* raw_stream = fopen("/dev/null", "r");
55   ASSERT_NE(nullptr, raw_stream);
56   {
57     ScopedFstream scoped_stream(raw_stream);
58     ASSERT_EQ(raw_stream, scoped_stream.get());
59     ASSERT_EQ(raw_stream, *scoped_stream);
60     ASSERT_TRUE(scoped_stream);
61   }
62   // We don't have a direct way to see that the file was closed.
63 }
64 
65 TEST(ScopedFileTest, Reset) {
66   int raw_fd1 = open("/dev/null", O_RDONLY);
67   int raw_fd2 = open("/dev/zero", O_RDONLY);
68   ASSERT_GE(raw_fd1, 0);
69   ASSERT_GE(raw_fd2, 0);
70   {
71     ScopedFile scoped_file(raw_fd1);
72     ASSERT_EQ(raw_fd1, scoped_file.get());
73     scoped_file.reset(raw_fd2);
74     ASSERT_EQ(raw_fd2, scoped_file.get());
75     ASSERT_NE(0, close(raw_fd1));  // Should fail when closing twice.
76     scoped_file.reset();
77     ASSERT_NE(0, close(raw_fd2));
78     scoped_file.reset(open("/dev/null", O_RDONLY));
79     ASSERT_GE(scoped_file.get(), 0);
80   }
81 }
82 
83 TEST(ScopedFileTest, Release) {
84   int raw_fd = open("/dev/null", O_RDONLY);
85   ASSERT_GE(raw_fd, 0);
86   {
87     ScopedFile scoped_file(raw_fd);
88     ASSERT_EQ(raw_fd, scoped_file.release());
89     ASSERT_FALSE(scoped_file);
90   }
91   ASSERT_EQ(0, close(raw_fd));
92 }
93 
94 TEST(ScopedFileTest, MoveCtor) {
95   int raw_fd1 = open("/dev/null", O_RDONLY);
96   int raw_fd2 = open("/dev/zero", O_RDONLY);
97   ASSERT_GE(raw_fd1, 0);
98   ASSERT_GE(raw_fd2, 0);
99   {
100     ScopedFile scoped_file1(ScopedFile{raw_fd1});
101     ScopedFile scoped_file2(std::move(scoped_file1));
102     ASSERT_EQ(-1, scoped_file1.get());
103     ASSERT_EQ(-1, *scoped_file1);
104     ASSERT_FALSE(scoped_file1);
105     ASSERT_EQ(raw_fd1, scoped_file2.get());
106 
107     scoped_file1.reset(raw_fd2);
108     ASSERT_EQ(raw_fd2, scoped_file1.get());
109   }
110   ASSERT_NE(0, close(raw_fd1));  // Should fail when closing twice.
111   ASSERT_NE(0, close(raw_fd2));
112 }
113 
114 TEST(ScopedFileTest, MoveAssignment) {
115   int raw_fd1 = open("/dev/null", O_RDONLY);
116   int raw_fd2 = open("/dev/zero", O_RDONLY);
117   ASSERT_GE(raw_fd1, 0);
118   ASSERT_GE(raw_fd2, 0);
119   {
120     ScopedFile scoped_file1(raw_fd1);
121     ScopedFile scoped_file2(raw_fd2);
122     scoped_file2 = std::move(scoped_file1);
123     ASSERT_EQ(-1, scoped_file1.get());
124     ASSERT_FALSE(scoped_file1);
125     ASSERT_EQ(raw_fd1, scoped_file2.get());
126     ASSERT_NE(0, close(raw_fd2));
127 
128     scoped_file1 = std::move(scoped_file2);
129     ASSERT_EQ(raw_fd1, scoped_file1.get());
130     ASSERT_EQ(-1, scoped_file2.get());
131   }
132   ASSERT_NE(0, close(raw_fd1));
133 }
134 
135 // File descriptors are capabilities and hence can be security critical. A
136 // failed close() suggests the memory ownership of the file is wrong and we
137 // might have leaked a capability.
138 TEST(ScopedFileTest, CloseFailureIsFatal) {
139   int raw_fd = open("/dev/null", O_RDONLY);
140   ASSERT_DEATH(
141       {
142         ScopedFile scoped_file(raw_fd);
143         ASSERT_EQ(0, close(raw_fd));
144       },
145       "");
146 }
147 
148 }  // namespace
149 }  // namespace base
150 }  // namespace perfetto
151