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 #define _GNU_SOURCE
17 
18 #include <unistd.h>
19 #include <stdio.h>
20 #include <dirent.h>
21 #include <string.h>
22 #include <sys/stat.h>
23 #include <sys/ioctl.h>
24 #include <sys/types.h>
25 #include <sys/wait.h>
26 #include <string.h>
27 #include <dlfcn.h>
28 #include <sys/time.h>
29 #include <sys/mman.h>
30 #include <sys/syscall.h>
31 #include <sys/resource.h>
32 #include <fcntl.h>
33 #include <pthread.h>
34 #include <unistd.h>
35 #include <sched.h>
36 #include <stdlib.h>
37 #include <errno.h>
38 
39 #define MSG_REQUEST  0x2
40 
41 struct voice_svc_write_msg {
42     __u32 msg_type;
43     __u8 payload[0];
44 };
45 
main()46 int main() {
47     int g_fd = 0;
48     char* dev_path = "/dev/voice_svc";
49 
50     g_fd = open(dev_path, O_RDWR);
51     if (g_fd < 0) {
52         return -1;
53     }
54 
55     int size = sizeof(struct voice_svc_write_msg) + 4;
56     char* msg = (char*)malloc(size);
57 
58     (msg + 4)[0] = 'A';
59     (msg + 4)[1] = 'A';
60     (msg + 4)[2] = 'A';
61     (msg + 4)[3] = 'A';
62     ((struct voice_svc_write_msg*)msg)->msg_type = MSG_REQUEST;
63 
64     int i;
65     for (i = 0; i < 20; ++i) {
66         write(g_fd, msg, size);
67         sleep(1);
68     }
69 
70     return 0;
71 }
72