1 /*
2  * Copyright (c) 2023 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #include "virtual_device.h"
17 
18 #include <iostream>
19 #include <map>
20 
21 #include <unistd.h>
22 
23 #include "devicestatus_define.h"
24 #include "fi_log.h"
25 
26 #undef LOG_TAG
27 #define LOG_TAG "VirtualDevice"
28 
29 namespace OHOS {
30 namespace Msdp {
31 namespace DeviceStatus {
32 namespace {
33 constexpr size_t DEFAULT_BUF_SIZE { 1024 };
34 constexpr int32_t MINIMUM_INTERVAL_ALLOWED { 1 };
35 constexpr int32_t MAXIMUM_INTERVAL_ALLOWED { 100 };
36 } // namespace
37 
VirtualDevice(const std::string & node)38 VirtualDevice::VirtualDevice(const std::string &node)
39 {
40     inputDev_ = std::make_unique<VInputDevice>(node);
41     inputDev_->Open();
42 }
43 
FindDeviceNode(const std::string & name,std::string & node)44 bool VirtualDevice::FindDeviceNode(const std::string &name, std::string &node)
45 {
46     CALL_DEBUG_ENTER;
47     std::map<std::string, std::string> nodes;
48     GetInputDeviceNodes(nodes);
49     FI_HILOGD("There are %{public}zu device nodes", nodes.size());
50 
51     std::map<std::string, std::string>::const_iterator cItr = nodes.find(name);
52     if (cItr == nodes.cend()) {
53         FI_HILOGE("No virtual stylus were found");
54         return false;
55     }
56     FI_HILOGD("Node name : \'%{public}s\'", cItr->second.c_str());
57     std::ostringstream ss;
58     ss << "/dev/input/" << cItr->second;
59     node = ss.str();
60     return true;
61 }
62 
Execute(std::vector<std::string> & results)63 void VirtualDevice::Execute(std::vector<std::string> &results)
64 {
65     CALL_DEBUG_ENTER;
66     char buffer[DEFAULT_BUF_SIZE] {};
67     FILE *pin = popen("cat /proc/bus/input/devices", "r");
68     if (pin == nullptr) {
69         FI_HILOGE("Failed to popen command");
70         return;
71     }
72     while (!feof(pin)) {
73         if (fgets(buffer, sizeof(buffer), pin) != nullptr) {
74             results.push_back(buffer);
75         }
76     }
77     FI_HILOGD("Close phandle");
78     pclose(pin);
79 }
80 
GetInputDeviceNodes(std::map<std::string,std::string> & nodes)81 void VirtualDevice::GetInputDeviceNodes(std::map<std::string, std::string> &nodes)
82 {
83     CALL_DEBUG_ENTER;
84     std::vector<std::string> results;
85     Execute(results);
86     if (results.empty()) {
87         FI_HILOGE("Failed to list devices");
88         return;
89     }
90     const std::string kname { "Name=\"" };
91     const std::string kevent { "event" };
92     std::string name;
93     for (const auto &res : results) {
94         FI_HILOGD("res:%{public}s", res.c_str());
95         if (res[0] == 'N') {
96             std::string::size_type spos = res.find(kname);
97             if (spos != std::string::npos) {
98                 spos += kname.size();
99                 std::string::size_type tpos = res.find("\"", spos);
100                 if (tpos != std::string::npos) {
101                     name = res.substr(spos, tpos - spos);
102                 }
103             }
104         } else if (!name.empty() && (res[0] == 'H')) {
105             std::string::size_type spos = res.find(kevent);
106             if (spos != std::string::npos) {
107                 std::map<std::string, std::string>::const_iterator cItr = nodes.find(name);
108                 if (cItr != nodes.end()) {
109                     nodes.erase(cItr);
110                 }
111                 std::string::size_type tpos = spos + kevent.size();
112                 while (std::isalnum(res[tpos])) {
113                     ++tpos;
114                 }
115                 auto [_, ret] = nodes.emplace(name, res.substr(spos, tpos - spos));
116                 if (!ret) {
117                     FI_HILOGW("name is duplicated");
118                 }
119                 name.clear();
120             }
121         }
122     }
123 }
124 
SendEvent(uint16_t type,uint16_t code,int32_t value)125 int32_t VirtualDevice::SendEvent(uint16_t type, uint16_t code, int32_t value)
126 {
127     CALL_DEBUG_ENTER;
128     CHKPR(inputDev_, RET_ERR);
129     inputDev_->SendEvent(type, code, value);
130 
131     if ((type == EV_SYN) && (code == SYN_REPORT)) {
132         std::this_thread::sleep_for(std::chrono::milliseconds(minimumInterval_));
133     }
134     return RET_OK;
135 }
136 
GetName() const137 std::string VirtualDevice::GetName() const
138 {
139     if (!name_.empty()) {
140         return name_;
141     }
142     if (inputDev_ != nullptr) {
143         return inputDev_->GetName();
144     }
145     return {};
146 }
147 
SetMinimumInterval(int32_t interval)148 void VirtualDevice::SetMinimumInterval(int32_t interval)
149 {
150     minimumInterval_ = std::max(MINIMUM_INTERVAL_ALLOWED, std::min(interval, MAXIMUM_INTERVAL_ALLOWED));
151 }
152 } // namespace DeviceStatus
153 } // namespace Msdp
154 } // namespace OHOS