ubuntu 下dbus的环境搭建和使用

从https://launchpad.net/ubuntu/+source/dbus/1.10.6-1ubuntu2下载需要的dbus包，然后解压，./configure make && make install

client.c

1. #include <stdio.h>
2. #include <stdlib.h>
3. #include <dbus/dbus.h>
4. #include <unistd.h>
5. const int RES_SUCCESS = -1;
6. const int RES_FAILED  = 0;
7. int my_dbus_initialization(char const * _bus_name, DBusConnection ** _conn) {
8. DBusError err;
9. int ret;
10. dbus_error_init(&err);
11. *_conn = dbus_bus_get(DBUS_BUS_SESSION, &err);
12. if(dbus_error_is_set(&err)) {
13. printf("Connection Error\n");
14. dbus_error_free(&err);
15. return RES_FAILED;
16. }
17. ret = dbus_bus_request_name(*_conn, _bus_name, DBUS_NAME_FLAG_REPLACE_EXISTING, &err);
18. if(dbus_error_is_set(&err)){
19. printf("Requece name error \n");
20. dbus_error_free(&err);
21. return RES_FAILED;
22. }
23. if(DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER != ret) {
24. return RES_FAILED;
25. }
26. return RES_SUCCESS;
27. }
28. int my_dbus_send_sigal(DBusConnection * conn) {
29. dbus_uint32_t serial = 0;
30. DBusMessage* msg;
31. DBusMessageIter args;
32. char sigvalue[20] = "liyiwen";
33. msg = dbus_message_new_signal("/test/signal/Object",  // object name
34. "test.signal.Type",     // interface name
35. "Test");                // name of signal
36. if (NULL == msg) {
37. printf("Message Null");
38. return RES_FAILED;
39. }
40. dbus_message_iter_init_append(msg, &args);
41. printf("%s\n", sigvalue);
42. dbus_uint32_t my_age = 10;
43. if(!dbus_message_iter_append_basic(&args, DBUS_TYPE_UINT32, &my_age)) {
44. printf("Out of memory\n");
45. return RES_FAILED;
46. }
47. if(!dbus_connection_send(conn, msg, &serial)) {
48. printf("Out of memory");
49. return RES_FAILED;
50. }
51. dbus_connection_flush(conn);
52. dbus_message_unref(msg);
53. return RES_SUCCESS;
54. }
55. int main(int agrc, char** argv)
56. {
57. DBusConnection * conn;
58. printf("Start\n");
59. if (RES_FAILED == my_dbus_initialization("test.method.client", &conn)) {
60. exit(1);
61. }
62. my_dbus_send_sigal(conn);
63. while(1){sleep(10);}
64. return 0;
65. }
66. sercer.c
67. 1. #include <stdio.h>
    2. #include <stdlib.h>
    3. #include <dbus/dbus.h>
    4. #include <unistd.h>
    5. const int RES_SUCCESS = -1;
    6. const int RES_FAILED  = 0;
    7. int my_dbus_initialization(char const * _bus_name, DBusConnection **_conn) {
    8. DBusError err;
    9. int ret;
    10. dbus_error_init(&err);
    11. *_conn = dbus_bus_get(DBUS_BUS_SESSION, &err);
    12. if(dbus_error_is_set(&err)) {
    13. printf("Connection Error(%s) \n", err.message);
    14. dbus_error_free(&err);
    15. return RES_FAILED;
    16. }
    17. ret = dbus_bus_request_name(*_conn, _bus_name, DBUS_NAME_FLAG_REPLACE_EXISTING, &err);
    18. if(dbus_error_is_set(&err)){
    19. printf("Requece name error(%s) \n", err.message);
    20. dbus_error_free(&err);
    21. return RES_FAILED;
    22. }
    23. if(DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER != ret) {
    24. return RES_FAILED;
    25. }
    26. return RES_SUCCESS;
    27. }
    28. int main(int agrc, char** argv)
    29. {
    30. DBusError err;
    31. DBusMessage* msg;
    32. DBusMessageIter args;
    33. dbus_error_init(&err);
    34. DBusConnection *conn;
    35. if (RES_FAILED == my_dbus_initialization("test.method.server", &conn)) {
    36. exit(1);
    37. }
    38. dbus_bus_add_match(conn, "type='signal', interface='test.signal.Type'", &err);
    39. dbus_connection_flush(conn);
    40. if(dbus_error_is_set(&err)) {
    41. printf("dbus_bus_add_match err (%s)", err.message);
    42. return RES_FAILED;
    43. }
    44. while(1) {
    45. dbus_connection_read_write(conn, 0);
    46. msg = dbus_connection_pop_message(conn);
    47. if(NULL == msg) {
    48. sleep(1);
    49. continue;
    50. }
    51. if(dbus_message_is_signal(msg, "test.signal.Type", "Test")) {
    52. if(!dbus_message_iter_init(msg, &args)) {
    53. printf("dbus_message_iter_init error, msg has no arguments!\n");
    54. }
    55. else if (DBUS_TYPE_UINT32 != dbus_message_iter_get_arg_type(&args)){
    56. printf("not a uint 32 type !\n");
    57. }
    58. else {
    59. dbus_uint32_t my_age = 0;
    60. dbus_message_iter_get_basic(&args, &my_age);
    61. printf("Got signal with value %d\n", my_age);
    62. }
    63. }
    64. dbus_message_unref(msg);
    65. }
    66. return 0;
    67. }
    68. 1. http://dbus.freedesktop.org/doc/dbus-specification.html  这当然是最权威最重要的资料，但我觉得不是一个很好的入门资料。
        2. http://dbus.freedesktop.org/doc/dbus-tutorial.html 这里面有一些不错的例子，对Names 的解释也很好，但用的是 glib 的 binding，不能探究更底层的动作一度还是让我云里雾里。
        3. http://dbus.freedesktop.org/doc/api/html/group__DBusMessage.html  DBus 的 C 编程接口的在线文档，非常棒也非常有用
        4. http://dbus.freedesktop.org/doc/dbus/libdbus-tutorial.html 如何用 C API 层面的 DBus ，相见恨晚。