1 #include 
     
       2 #include 
      
        3 #include "dir-watch.h"     //add  4   5 #define MAX_DIRS_TO_WATCH 128 6  7 /* use a static array to avoid handling OOM */ 8 static int fds[MAX_DIRS_TO_WATCH]; 9 static int num_fds = 0;10 void bus_watch_directory(const char *dir, BusContext *context);    //add11 //add function12 void bus_set_watched_dirs(BusContext *context,DBusList **directories)13 {14    DBusList *link=_dbus_list_get_first_link(directories);15    while(link!=NULL)16    {17      bus_watch_directory(link->data,context);18      link=_dbus_list_get_next_link(directories,link);19    }20 }
      
     

#include "dir-watch.h"

#!/bin/shif test -z "$DBUS_SESSION_BUS_ADDRESS" ; then## if not found, launch a new oneeval `dbus-launch --sh-syntax --exit-with-session`echo "D-Bus per-session daemon address is: $DBUS_SESSION_BUS_ADDRESS"fi

messagebus:$1$$YwM2vWXS3L4EbCfJU4I7N0:500:500:Linux User,,,:/home/messagebus:/bi   //为adduser messagebus命令生成

1 /*  2 * Example low-level D-Bus code.  3 * Written by Matthew Johnson 
     
        4 *  5 * This code has been released into the Public Domain.  6 * You may do whatever you like with it.  7 */  8 #include 
      
         9 #include 
       
         10 #include 
        
          11 #include 
         
           12 #include 
          
            13 14 /** 15 * Connect to the DBUS bus and send a broadcast signal 16 */ 17 void sendsignal(char* sigvalue) 18 { 19 DBusMessage* msg; 20 DBusMessageIter args; 21 DBusConnection* conn; 22 DBusError err; 23 int ret; 24 dbus_uint32_t serial = 0; 25 26 printf("Sending signal with value %s\n", sigvalue); 27 28 // initialise the error value 29 dbus_error_init(&err); 30 31 // connect to the DBUS system bus, and check for errors 32 conn = dbus_bus_get(DBUS_BUS_SESSION, &err); 33 if (dbus_error_is_set(&err)) { 34 fprintf(stderr, "Connection Error (%s)\n", err.message); 35 dbus_error_free(&err); 36 } 37 if (NULL == conn) { 38 exit(1); 39 } 40 41 // register our name on the bus, and check for errors 42 ret = dbus_bus_request_name(conn, "test.signal.source", DBUS_NAME_FLAG_REPLACE_EXISTING , &err); 43 if (dbus_error_is_set(&err)) { 44 fprintf(stderr, "Name Error (%s)\n", err.message); 45 dbus_error_free(&err); 46 } 47 if (DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER != ret) { 48 exit(1); 49 } 50 51 // create a signal & check for errors 52 msg = dbus_message_new_signal("/test/signal/Object", // object name of the signal 53 "test.signal.Type", // interface name of the signal 54 "Test"); // name of the signal 55 if (NULL == msg) 56 { 57 fprintf(stderr, "Message Null\n"); 58 exit(1); 59 } 60 61 // append arguments onto signal 62 dbus_message_iter_init_append(msg, &args); 63 if (!dbus_message_iter_append_basic(&args, DBUS_TYPE_STRING, &sigvalue)) { 64 fprintf(stderr, "Out Of Memory!\n"); 65 exit(1); 66 } 67 68 // send the message and flush the connection 69 if (!dbus_connection_send(conn, msg, &serial)) { 70 fprintf(stderr, "Out Of Memory!\n"); 71 exit(1); 72 } 73 dbus_connection_flush(conn); 74 75 printf("Signal Sent\n"); 76 77 // free the message 78 dbus_message_unref(msg); 79 } 80 81 /** 82 * Call a method on a remote object 83 */ 84 void query(char* param) 85 { 86 DBusMessage* msg; 87 DBusMessageIter args; 88 DBusConnection* conn; 89 DBusError err; 90 DBusPendingCall* pending; 91 int ret; 92 bool stat; 93 dbus_uint32_t level; 94 95 printf("Calling remote method with %s\n", param); 96 97 // initialiset the errors 98 dbus_error_init(&err); 99 100 // connect to the system bus and check for errors101 conn = dbus_bus_get(DBUS_BUS_SESSION, &err);102 if (dbus_error_is_set(&err)) {103 fprintf(stderr, "Connection Error (%s)\n", err.message);104 dbus_error_free(&err);105 }106 if (NULL == conn) {107 exit(1);108 }109 110 // request our name on the bus111 ret = dbus_bus_request_name(conn, "test.method.caller", DBUS_NAME_FLAG_REPLACE_EXISTING , &err);112 if (dbus_error_is_set(&err)) {113 fprintf(stderr, "Name Error (%s)\n", err.message);114 dbus_error_free(&err);115 }116 if (DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER != ret) {117 exit(1);118 }119 120 // create a new method call and check for errors121 msg = dbus_message_new_method_call("test.method.server",// target for the method call122 "/test/method/Object", // object to call on123 "test.method.Type", // interface to call on124 "Method"); // method name125 if (NULL == msg) {126 fprintf(stderr, "Message Null\n");127 exit(1);128 }129 130 // append arguments131 dbus_message_iter_init_append(msg, &args);132 if (!dbus_message_iter_append_basic(&args, DBUS_TYPE_STRING, &param)) {133 fprintf(stderr, "Out Of Memory!\n");134 exit(1);135 }136 137 // send message and get a handle for a reply138 if (!dbus_connection_send_with_reply (conn, msg, &pending, -1)) { // -1 is default timeout139 fprintf(stderr, "Out Of Memory!\n");140 exit(1);141 }142 if (NULL == pending) {143 fprintf(stderr, "Pending Call Null\n");144 exit(1);145 }146 dbus_connection_flush(conn);147 148 printf("Request Sent\n");149 150 // free message151 dbus_message_unref(msg);152 153 // block until we recieve a reply154 dbus_pending_call_block(pending);155 156 // get the reply message157 msg = dbus_pending_call_steal_reply(pending);158 if (NULL == msg) {159 fprintf(stderr, "Reply Null\n");160 exit(1);161 }162 // free the pending message handle163 dbus_pending_call_unref(pending);164 165 // read the parameters166 if (!dbus_message_iter_init(msg, &args))167 fprintf(stderr, "Message has no arguments!\n");168 else if (DBUS_TYPE_BOOLEAN != dbus_message_iter_get_arg_type(&args))169 fprintf(stderr, "Argument is not boolean!\n");170 else171 dbus_message_iter_get_basic(&args, &stat);172 173 if (!dbus_message_iter_next(&args))174 fprintf(stderr, "Message has too few arguments!\n");175 else if (DBUS_TYPE_UINT32 != dbus_message_iter_get_arg_type(&args))176 fprintf(stderr, "Argument is not int!\n");177 else178 dbus_message_iter_get_basic(&args, &level);179 180 printf("Got Reply: %d, %d\n", stat, level);181 182 // free reply183 dbus_message_unref(msg); 184 }185 186 187 void reply_to_method_call(DBusMessage* msg, DBusConnection* conn)188 {189 DBusMessage* reply;190 DBusMessageIter args;191 bool stat = true;192 dbus_uint32_t level = 21614;193 dbus_uint32_t serial = 0;194 char* param = "";195 196 // read the arguments197 if (!dbus_message_iter_init(msg, &args))198 fprintf(stderr, "Message has no arguments!\n");199 else if (DBUS_TYPE_STRING != dbus_message_iter_get_arg_type(&args))200 fprintf(stderr, "Argument is not string!\n");201 else202 dbus_message_iter_get_basic(&args, &param);203 204 printf("Method called with %s\n", param);205 206 // create a reply from the message207 reply = dbus_message_new_method_return(msg);208 209 // add the arguments to the reply210 dbus_message_iter_init_append(reply, &args);211 if (!dbus_message_iter_append_basic(&args, DBUS_TYPE_BOOLEAN, &stat)) {212 fprintf(stderr, "Out Of Memory!\n");213 exit(1);214 }215 if (!dbus_message_iter_append_basic(&args, DBUS_TYPE_UINT32, &level)) {216 fprintf(stderr, "Out Of Memory!\n");217 exit(1);218 }219 220 // send the reply && flush the connection221 if (!dbus_connection_send(conn, reply, &serial)) {222 fprintf(stderr, "Out Of Memory!\n");223 exit(1);224 }225 dbus_connection_flush(conn);226 227 // free the reply228 dbus_message_unref(reply);229 }230 231 232 233 /**234 * Server that exposes a method call and waits for it to be called235 */236 void listen()237 {238 DBusMessage* msg;239 DBusMessage* reply;240 DBusMessageIter args;241 DBusConnection* conn;242 DBusError err;243 int ret;244 char* param;245 246 printf("Listening for method calls\n");247 248 // initialise the error249 dbus_error_init(&err);250 251 // connect to the bus and check for errors252 conn = dbus_bus_get(DBUS_BUS_SESSION, &err);253 if (dbus_error_is_set(&err)) {254 fprintf(stderr, "Connection Error (%s)\n", err.message);255 dbus_error_free(&err);256 }257 if (NULL == conn) {258 fprintf(stderr, "Connection Null\n");259 exit(1);260 }261 262 // request our name on the bus and check for errors263 ret = dbus_bus_request_name(conn, "test.method.server",264 DBUS_NAME_FLAG_REPLACE_EXISTING , &err);265 if (dbus_error_is_set(&err)) {266 fprintf(stderr, "Name Error (%s)\n", err.message);267 dbus_error_free(&err);268 }269 if (DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER != ret) {270 fprintf(stderr, "Not Primary Owner (%d)\n", ret);271 exit(1);272 }273 274 // loop, testing for new messages275 while (true) {276 // non blocking read of the next available message277 dbus_connection_read_write(conn, 0);278 msg = dbus_connection_pop_message(conn);279 280 // loop again if we haven't got a message281 if (NULL == msg) {282 sleep(1);283 continue;284 }285 286 // check this is a method call for the right interface & method287 if (dbus_message_is_method_call(msg, "test.method.Type", "Method"))288 reply_to_method_call(msg, conn);289 290 // free the message291 dbus_message_unref(msg);292 }293 }294 295 296 297 /**298 * Listens for signals on the bus299 */300 void receive()301 {302 DBusMessage* msg;303 DBusMessageIter args;304 DBusConnection* conn;305 DBusError err;306 int ret;307 char* sigvalue;308 309 printf("Listening for signals\n");310 311 // initialise the errors312 dbus_error_init(&err);313 314 // connect to the bus and check for errors315 conn = dbus_bus_get(DBUS_BUS_SESSION, &err);316 if (dbus_error_is_set(&err)) {317 fprintf(stderr, "Connection Error (%s)\n", err.message);318 dbus_error_free(&err);319 }320 if (NULL == conn) {321 exit(1);322 }323 324 // request our name on the bus and check for errors325 ret = dbus_bus_request_name(conn, "test.signal.sink", DBUS_NAME_FLAG_REPLACE_EXISTING , &err);326 if (dbus_error_is_set(&err)) {327 fprintf(stderr, "Name Error (%s)\n", err.message);328 dbus_error_free(&err);329 }330 if (DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER != ret) {331 exit(1);332 }333 334 // add a rule for which messages we want to see335 dbus_bus_add_match(conn, "type='signal',interface='test.signal.Type'", &err); // see signals from the given interface336 dbus_connection_flush(conn);337 if (dbus_error_is_set(&err)) {338 fprintf(stderr, "Match Error (%s)\n", err.message);339 exit(1);340 }341 printf("Match rule sent\n");342 343 // loop listening for signals being emmitted344 while (true) {345 346 // non blocking read of the next available message347 dbus_connection_read_write(conn, 0);348 msg = dbus_connection_pop_message(conn);349 350 // loop again if we haven't read a message351 if (NULL == msg) {352 sleep(1);353 continue;354 }355 356 // check if the message is a signal from the correct interface and with the correct name357 if (dbus_message_is_signal(msg, "test.signal.Type", "Test")) {358 359 // read the parameters360 if (!dbus_message_iter_init(msg, &args))361 fprintf(stderr, "Message Has No Parameters\n");362 else if (DBUS_TYPE_STRING != dbus_message_iter_get_arg_type(&args))363 fprintf(stderr, "Argument is not string!\n");364 else365 dbus_message_iter_get_basic(&args, &sigvalue);366 367 printf("Got Signal with value %s\n", sigvalue);368 }369 370 // free the message371 dbus_message_unref(msg);372 }373 }374 375 376 377 int main(int argc, char** argv)378 {379 if (2 > argc) {380 printf ("Syntax: dbus-example [send|receive|listen|query] [
           ]\n");381 return 1;382 }383 char* param = "no param";384 if (3 >= argc && NULL != argv[2]) param = argv[2];385 if (0 == strcmp(argv[1], "send"))386 sendsignal(param);387 else if (0 == strcmp(argv[1], "receive"))388 receive();389 else if (0 == strcmp(argv[1], "listen"))390 listen();391 else if (0 == strcmp(argv[1], "query"))392 query(param);393 else {394 printf ("Syntax: dbus-example [send|receive|listen|query] [
           ]\n");395 return 1;396 }397 return 0;398 }
          
         
        
       
      
     

错误1:$ gcc test.ctest.c:8:23: 错误： dbus/dbus.h：No such file or directory......$错误提示，dbus库的头文件位置不正确(如果已经安装了dbus的话)$ sudo updatedb$ sudo locate dbus.h (查看dbus.h的所在位置)/usr/local/include/dbus-1.0/dbus/dbus.h/usr/include/dbus-1.0/dbus/dbus.h看来dbus.h的存放位置的确不正确，这可能是由于dbus-1.0的安装位置有问题，没关系，调整一下dbus的头文件位置就可以了(调整方法如下):root@zxl:/usr/include# ln -sf dbus-1.0/dbus错误2:$ gcc test.c在包含自 test.c：8 的文件中:/usr/include/dbus/dbus.h:29:33: 错误： dbus/dbus-arch-deps.h：No such file or directory......依然有头文件无法正确定位的问题，从错误提示来看，该文件应该在/usr/include/dbus/目录下，可是进入该目录查看竟然没有，那就在整个系统中查找该文件。root@zxl:/usr/include/dbus# locate dbus-arch-deps.h/usr/local/lib/dbus-1.0/include/dbus/dbus-arch-deps.h/usr/lib/dbus-1.0/include/dbus/dbus-arch-deps.h将该文件复制到/usr/include/dbus目录下错误3:$ gcc test.c......test.c:(.text+0xbb6): undefined reference to `dbus_message_iter_get_basic'test.c:(.text+0xbd4): undefined reference to `dbus_message_unref'collect2: ld 返回 1需要连接动态库dbus$ cd /usr/lib$ ls *dbus*libdbus-1.a   libdbus-1.so.3      libdbus-glib-1.solibdbus-1.la libdbus-1.so.3.2.0 libdbus-glib-1.so.2libdbus-1.so libdbus-glib-1.a    libdbus-glib-1.so.2.1.0$ gcc test.c -l dbus-1 -o dbus

$ ./dbus receiveListening for signalsMatch rule sentGot Signal with value doctorQBW　　$ ./dbus send doctorQBW    (再开一个标签)Sending signal with value doctorQBWSignal Sent

$ arm-hismall-linux-gcc send.c

$ arm-hismall-linux-gcc dbustest.c -o dbustest -I./ -L ./ -ldbus-1

D-Bus per-session daemon address is: unix:path=/tmp/dbus-pebh4YY2Pp,guid=3ab7577588cdf4e7773663ae38792d8d

export DBUS_SESSION_BUS_ADDRESS=‘unix:path=/tmp/dbus-pebh4YY2Pp’