1 /*
2  * Copyright (C) 2010 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 <errno.h>
18 #include <fcntl.h>
19 #include <stdlib.h>
20 #include <string.h>
21 #include <sys/stat.h>
22 #include <sys/types.h>
23 #include <linux/keychord.h>
24 #include <unistd.h>
25 
26 #include "init.h"
27 #include "log.h"
28 #include "property_service.h"
29 #include "service.h"
30 
31 static struct input_keychord *keychords = 0;
32 static int keychords_count = 0;
33 static int keychords_length = 0;
34 static int keychord_fd = -1;
35 
add_service_keycodes(Service * svc)36 void add_service_keycodes(Service* svc)
37 {
38     struct input_keychord *keychord;
39     size_t i, size;
40 
41     if (!svc->keycodes().empty()) {
42         /* add a new keychord to the list */
43         size = sizeof(*keychord) + svc->keycodes().size() * sizeof(keychord->keycodes[0]);
44         keychords = (input_keychord*) realloc(keychords, keychords_length + size);
45         if (!keychords) {
46             ERROR("could not allocate keychords\n");
47             keychords_length = 0;
48             keychords_count = 0;
49             return;
50         }
51 
52         keychord = (struct input_keychord *)((char *)keychords + keychords_length);
53         keychord->version = KEYCHORD_VERSION;
54         keychord->id = keychords_count + 1;
55         keychord->count = svc->keycodes().size();
56         svc->set_keychord_id(keychord->id);
57 
58         for (i = 0; i < svc->keycodes().size(); i++) {
59             keychord->keycodes[i] = svc->keycodes()[i];
60         }
61         keychords_count++;
62         keychords_length += size;
63     }
64 }
65 
handle_keychord()66 static void handle_keychord() {
67     int ret;
68     __u16 id;
69 
70     ret = read(keychord_fd, &id, sizeof(id));
71     if (ret != sizeof(id)) {
72         ERROR("could not read keychord id\n");
73         return;
74     }
75 
76     // Only handle keychords if adb is enabled.
77     std::string adb_enabled = property_get("init.svc.adbd");
78     if (adb_enabled == "running") {
79         Service* svc = ServiceManager::GetInstance().FindServiceByKeychord(id);
80         if (svc) {
81             INFO("Starting service %s from keychord\n", svc->name().c_str());
82             svc->Start();
83         } else {
84             ERROR("service for keychord %d not found\n", id);
85         }
86     }
87 }
88 
keychord_init()89 void keychord_init() {
90     ServiceManager::GetInstance().ForEachService(add_service_keycodes);
91 
92     // Nothing to do if no services require keychords.
93     if (!keychords) {
94         return;
95     }
96 
97     keychord_fd = TEMP_FAILURE_RETRY(open("/dev/keychord", O_RDWR | O_CLOEXEC));
98     if (keychord_fd == -1) {
99         ERROR("could not open /dev/keychord: %s\n", strerror(errno));
100         return;
101     }
102 
103     int ret = write(keychord_fd, keychords, keychords_length);
104     if (ret != keychords_length) {
105         ERROR("could not configure /dev/keychord %d: %s\n", ret, strerror(errno));
106         close(keychord_fd);
107     }
108 
109     free(keychords);
110     keychords = nullptr;
111 
112     register_epoll_handler(keychord_fd, handle_keychord);
113 }
114