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 "aidl_test_client_file_descriptors.h"
18 
19 #include <iostream>
20 #include <vector>
21 
22  #include <errno.h>
23 #include <string.h>
24 #include <unistd.h>
25 
26 #include <android-base/unique_fd.h>
27 
28 // libbase
29 using android::base::unique_fd;
30 
31 // libutils:
32 using android::sp;
33 
34 // libbinder:
35 using android::binder::Status;
36 
37 // generated
38 using android::aidl::tests::ITestService;
39 
40 using std::cerr;
41 using std::cout;
42 using std::endl;
43 using std::string;
44 using std::vector;
45 
46 namespace android {
47 namespace aidl {
48 namespace tests {
49 namespace client {
50 
51 #define FdByName(_fd) #_fd, _fd
52 
DoWrite(const string & name,const unique_fd & fd,const string & buf)53 bool DoWrite(const string& name, const unique_fd& fd, const string& buf) {
54   int wrote;
55 
56   while ((wrote = write(fd.get(), buf.data(), buf.size())) < 0 && errno == EINTR);
57 
58   if (wrote == (signed)buf.size()) {
59     return true;
60   }
61 
62   if (wrote < 0) {
63     cerr << "Error writing to file descriptor '" << name << "': "
64         << strerror(errno) << endl;
65   } else {
66     cerr << "File descriptor '" << name << "'accepted short data." << endl;
67   }
68 
69   return false;
70 }
71 
DoRead(const string & name,const unique_fd & fd,const string & expected)72 bool DoRead(const string& name, const unique_fd& fd, const string& expected) {
73   size_t length = expected.size();
74   int got;
75   string buf;
76   buf.resize(length);
77 
78   while ((got = read(fd.get(), &buf[0], length)) < 0 && errno == EINTR);
79 
80   if (got < 0) {
81     cerr << "Error reading from '" << name << "': " << strerror(errno) << endl;
82     return false;
83   }
84 
85   if (buf != expected) {
86     cerr << "Expected '" << expected << "' got '" << buf << "'" << endl;
87     return false;
88   }
89 
90   return true;
91 }
92 
DoPipe(unique_fd * read_side,unique_fd * write_side)93 bool DoPipe(unique_fd* read_side, unique_fd* write_side) {
94   int fds[2];
95   unique_fd return_fd;
96 
97   if (pipe(fds)) {
98     cout << "Error creating pipes: " << strerror(errno) << endl;
99     return false;
100   }
101 
102   read_side->reset(fds[0]);
103   write_side->reset(fds[1]);
104   return true;
105 }
106 
ConfirmFileDescriptors(const sp<ITestService> & s)107 bool ConfirmFileDescriptors(const sp<ITestService>& s) {
108   Status status;
109   cout << "Confirming passing and returning file descriptors works." << endl;
110 
111   unique_fd return_fd;
112   unique_fd read_fd;
113   unique_fd write_fd;
114 
115   if (!DoPipe(&read_fd, &write_fd)) {
116     return false;
117   }
118 
119   status = s->RepeatFileDescriptor(write_fd, &return_fd);
120 
121   if (!status.isOk()) {
122     cerr << "Could not repeat file descriptors." << endl;
123     return false;
124   }
125 
126   /* A note on some of the spookier stuff going on here: IIUC writes to pipes
127    * should be atomic and non-blocking so long as the total size doesn't exceed
128    * PIPE_BUF. We thus play a bit fast and loose with failure modes here.
129    */
130 
131   bool ret =
132       DoWrite(FdByName(return_fd), "ReturnString") &&
133       DoRead(FdByName(read_fd), "ReturnString");
134 
135   return ret;
136 }
137 
ConfirmFileDescriptorArrays(const sp<ITestService> & s)138 bool ConfirmFileDescriptorArrays(const sp<ITestService>& s) {
139   Status status;
140   cout << "Confirming passing and returning file descriptor arrays works." << endl;
141 
142   vector<unique_fd> array;
143   array.resize(2);
144 
145   if (!DoPipe(&array[0], &array[1])) {
146     return false;
147   }
148 
149   vector<unique_fd> repeated;
150   vector<unique_fd> reversed;
151 
152   status = s->ReverseFileDescriptorArray(array, &repeated, &reversed);
153 
154   if (!status.isOk()) {
155     cerr << "Could not reverse file descriptor array." << endl;
156     return false;
157   }
158 
159   bool ret =
160       DoWrite(FdByName(array[1]), "First") &&
161       DoWrite(FdByName(repeated[1]), "Second") &&
162       DoWrite(FdByName(reversed[0]), "Third") &&
163       DoRead(FdByName(reversed[1]), "FirstSecondThird");
164 
165   return ret;
166 }
167 
168 }  // namespace client
169 }  // namespace tests
170 }  // namespace aidl
171 }  // namespace android
172