1 /*
2 * Copyright (C) 2009 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 /* this program is used to read a set of system properties and their values
18 * from the emulator program and set them in the currently-running emulated
19 * system. It does so by connecting to the 'boot-properties' qemud service.
20 *
21 * This program should be run as root and called from
22 * /system/etc/init.goldfish.rc exclusively.
23 */
24
25 #define LOG_TAG "qemu-props"
26
27 #define DEBUG 1
28
29 #if DEBUG
30 # include <cutils/log.h>
31 # define DD(...) ALOGI(__VA_ARGS__)
32 #else
33 # define DD(...) ((void)0)
34 #endif
35
36 #include <cutils/properties.h>
37 #include <unistd.h>
38 #include <hardware/qemud.h>
39
40 /* Name of the qemud service we want to connect to.
41 */
42 #define QEMUD_SERVICE "boot-properties"
43
44 #define MAX_TRIES 5
45
main(void)46 int main(void)
47 {
48 int qemud_fd, count = 0;
49
50 /* try to connect to the qemud service */
51 {
52 int tries = MAX_TRIES;
53
54 while (1) {
55 qemud_fd = qemud_channel_open( "boot-properties" );
56 if (qemud_fd >= 0)
57 break;
58
59 if (--tries <= 0) {
60 DD("Could not connect after too many tries. Aborting");
61 return 1;
62 }
63
64 DD("waiting 1s to wait for qemud.");
65 sleep(1);
66 }
67 }
68
69 DD("connected to '%s' qemud service.", QEMUD_SERVICE);
70
71 /* send the 'list' command to the service */
72 if (qemud_channel_send(qemud_fd, "list", -1) < 0) {
73 DD("could not send command to '%s' service", QEMUD_SERVICE);
74 return 1;
75 }
76
77 /* read each system property as a single line from the service,
78 * until exhaustion.
79 */
80 for (;;)
81 {
82 #define BUFF_SIZE (PROPERTY_KEY_MAX + PROPERTY_VALUE_MAX + 2)
83 DD("receiving..");
84 char* q;
85 char temp[BUFF_SIZE];
86 int len = qemud_channel_recv(qemud_fd, temp, sizeof temp - 1);
87
88 /* lone NUL-byte signals end of properties */
89 if (len < 0 || len > BUFF_SIZE-1 || temp[0] == '\0')
90 break;
91
92 temp[len] = '\0'; /* zero-terminate string */
93
94 DD("received: %.*s", len, temp);
95
96 /* separate propery name from value */
97 q = strchr(temp, '=');
98 if (q == NULL) {
99 DD("invalid format, ignored.");
100 continue;
101 }
102 *q++ = '\0';
103
104 if (property_set(temp, q) < 0) {
105 DD("could not set property '%s' to '%s'", temp, q);
106 } else {
107 count += 1;
108 }
109 }
110
111
112 /* finally, close the channel and exit */
113 close(qemud_fd);
114 DD("exiting (%d properties set).", count);
115 return 0;
116 }
117