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mvidner/Makefile

Created October 2, 2012 11:14
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  1. mvidner revised this gist Oct 2, 2012. 2 changed files with 3 additions and 3 deletions.
    3 changes: 3 additions & 0 deletions Makefile
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,3 @@
    CFLAGS=`pkg-config --cflags dbus-1` -Wall
    LDFLAGS=`pkg-config --libs dbus-1`
    all: dbus-example
    3 changes: 0 additions & 3 deletions dbus-example.c
    View file
    Original file line number Diff line number Diff line change
    @@ -230,12 +230,9 @@ void reply_to_method_call(DBusMessage* msg, DBusConnection* conn)
    void listen()
    {
    DBusMessage* msg;
    DBusMessage* reply;
    DBusMessageIter args;
    DBusConnection* conn;
    DBusError err;
    int ret;
    char* param;

    printf("Listening for method calls\n");

  2. mvidner revised this gist Oct 2, 2012. 1 changed file with 2 additions and 2 deletions.
    4 changes: 2 additions & 2 deletions dbus-example.c
    View file
    Original file line number Diff line number Diff line change
    @@ -85,7 +85,7 @@ void query(const char* param)
    DBusError err;
    DBusPendingCall* pending;
    int ret;
    bool stat;
    dbus_bool_t stat;
    dbus_uint32_t level;

    printf("Calling remote method with %s\n", param);
    @@ -184,7 +184,7 @@ void reply_to_method_call(DBusMessage* msg, DBusConnection* conn)
    {
    DBusMessage* reply;
    DBusMessageIter args;
    bool stat = true;
    dbus_bool_t stat = true;
    dbus_uint32_t level = 21614;
    dbus_uint32_t serial = 0;
    const char* param = "";
  3. mvidner revised this gist Oct 2, 2012. 1 changed file with 8 additions and 8 deletions.
    16 changes: 8 additions & 8 deletions dbus-example.c
    View file
    Original file line number Diff line number Diff line change
    @@ -69,9 +69,9 @@ void sendsignal(const char* sigvalue)

    printf("Signal Sent\n");

    // free the message and close the connection
    // free the message and unref the connection
    dbus_message_unref(msg);
    dbus_connection_close(conn);
    dbus_connection_unref(conn);
    }

    /**
    @@ -175,9 +175,9 @@ void query(const char* param)

    printf("Got Reply: %d, %d\n", stat, level);

    // free reply and close connection
    // free reply and unref connection
    dbus_message_unref(msg);
    dbus_connection_close(conn);
    dbus_connection_unref(conn);
    }

    void reply_to_method_call(DBusMessage* msg, DBusConnection* conn)
    @@ -284,8 +284,8 @@ void listen()
    dbus_message_unref(msg);
    }

    // close the connection
    dbus_connection_close(conn);
    // unref the connection
    dbus_connection_unref(conn);
    }

    /**
    @@ -364,8 +364,8 @@ void receive()
    // free the message
    dbus_message_unref(msg);
    }
    // close the connection
    dbus_connection_close(conn);
    // unref the connection
    dbus_connection_unref(conn);
    }

    int main(int argc, char** argv)
  4. mvidner revised this gist Oct 2, 2012. 1 changed file with 6 additions and 6 deletions.
    12 changes: 6 additions & 6 deletions dbus-example.c
    View file
    Original file line number Diff line number Diff line change
    @@ -23,8 +23,8 @@ void sendsignal(const char* sigvalue)
    // initialise the error value
    dbus_error_init(&err);

    // connect to the DBUS system bus, and check for errors
    conn = dbus_bus_get(DBUS_BUS_SYSTEM, &err);
    // connect to the DBUS session bus, and check for errors
    conn = dbus_bus_get(DBUS_BUS_SESSION, &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Connection Error (%s)\n", err.message);
    dbus_error_free(&err);
    @@ -93,8 +93,8 @@ void query(const char* param)
    // initialiset the errors
    dbus_error_init(&err);

    // connect to the system bus and check for errors
    conn = dbus_bus_get(DBUS_BUS_SYSTEM, &err);
    // connect to the session bus and check for errors
    conn = dbus_bus_get(DBUS_BUS_SESSION, &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Connection Error (%s)\n", err.message);
    dbus_error_free(&err);
    @@ -243,7 +243,7 @@ void listen()
    dbus_error_init(&err);

    // connect to the bus and check for errors
    conn = dbus_bus_get(DBUS_BUS_SYSTEM, &err);
    conn = dbus_bus_get(DBUS_BUS_SESSION, &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Connection Error (%s)\n", err.message);
    dbus_error_free(&err);
    @@ -306,7 +306,7 @@ void receive()
    dbus_error_init(&err);

    // connect to the bus and check for errors
    conn = dbus_bus_get(DBUS_BUS_SYSTEM, &err);
    conn = dbus_bus_get(DBUS_BUS_SESSION, &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Connection Error (%s)\n", err.message);
    dbus_error_free(&err);
  5. mvidner revised this gist Oct 2, 2012. 1 changed file with 5 additions and 4 deletions.
    9 changes: 5 additions & 4 deletions dbus-example.c
    View file
    Original file line number Diff line number Diff line change
    @@ -4,11 +4,12 @@
    #include <unistd.h>
    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>

    /**
    * Connect to the DBUS bus and send a broadcast signal
    */
    void sendsignal(char* sigvalue)
    void sendsignal(const char* sigvalue)
    {
    DBusMessage* msg;
    DBusMessageIter args;
    @@ -76,7 +77,7 @@ void sendsignal(char* sigvalue)
    /**
    * Call a method on a remote object
    */
    void query(char* param)
    void query(const char* param)
    {
    DBusMessage* msg;
    DBusMessageIter args;
    @@ -186,7 +187,7 @@ void reply_to_method_call(DBusMessage* msg, DBusConnection* conn)
    bool stat = true;
    dbus_uint32_t level = 21614;
    dbus_uint32_t serial = 0;
    char* param = "";
    const char* param = "";

    // read the arguments
    if (!dbus_message_iter_init(msg, &args))
    @@ -373,7 +374,7 @@ int main(int argc, char** argv)
    printf ("Syntax: dbus-example [send|receive|listen|query] [<param>]\n");
    return 1;
    }
    char* param = "no param";
    const char* param = "no param";
    if (3 >= argc && NULL != argv[2]) param = argv[2];
    if (0 == strcmp(argv[1], "send"))
    sendsignal(param);
  6. mvidner created this gist Oct 2, 2012.
    391 changes: 391 additions & 0 deletions dbus-example.c
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,391 @@
    #define DBUS_API_SUBJECT_TO_CHANGE
    #include <dbus/dbus.h>
    #include <stdbool.h>
    #include <unistd.h>
    #include <stdio.h>
    #include <stdlib.h>

    /**
    * Connect to the DBUS bus and send a broadcast signal
    */
    void sendsignal(char* sigvalue)
    {
    DBusMessage* msg;
    DBusMessageIter args;
    DBusConnection* conn;
    DBusError err;
    int ret;
    dbus_uint32_t serial = 0;

    printf("Sending signal with value %s\n", sigvalue);

    // initialise the error value
    dbus_error_init(&err);

    // connect to the DBUS system bus, and check for errors
    conn = dbus_bus_get(DBUS_BUS_SYSTEM, &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Connection Error (%s)\n", err.message);
    dbus_error_free(&err);
    }
    if (NULL == conn) {
    exit(1);
    }

    // register our name on the bus, and check for errors
    ret = dbus_bus_request_name(conn, "test.signal.source", DBUS_NAME_FLAG_REPLACE_EXISTING , &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Name Error (%s)\n", err.message);
    dbus_error_free(&err);
    }
    if (DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER != ret) {
    exit(1);
    }

    // create a signal & check for errors
    msg = dbus_message_new_signal("/test/signal/Object", // object name of the signal
    "test.signal.Type", // interface name of the signal
    "Test"); // name of the signal
    if (NULL == msg)
    {
    fprintf(stderr, "Message Null\n");
    exit(1);
    }

    // append arguments onto signal
    dbus_message_iter_init_append(msg, &args);
    if (!dbus_message_iter_append_basic(&args, DBUS_TYPE_STRING, &sigvalue)) {
    fprintf(stderr, "Out Of Memory!\n");
    exit(1);
    }

    // send the message and flush the connection
    if (!dbus_connection_send(conn, msg, &serial)) {
    fprintf(stderr, "Out Of Memory!\n");
    exit(1);
    }
    dbus_connection_flush(conn);

    printf("Signal Sent\n");

    // free the message and close the connection
    dbus_message_unref(msg);
    dbus_connection_close(conn);
    }

    /**
    * Call a method on a remote object
    */
    void query(char* param)
    {
    DBusMessage* msg;
    DBusMessageIter args;
    DBusConnection* conn;
    DBusError err;
    DBusPendingCall* pending;
    int ret;
    bool stat;
    dbus_uint32_t level;

    printf("Calling remote method with %s\n", param);

    // initialiset the errors
    dbus_error_init(&err);

    // connect to the system bus and check for errors
    conn = dbus_bus_get(DBUS_BUS_SYSTEM, &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Connection Error (%s)\n", err.message);
    dbus_error_free(&err);
    }
    if (NULL == conn) {
    exit(1);
    }

    // request our name on the bus
    ret = dbus_bus_request_name(conn, "test.method.caller", DBUS_NAME_FLAG_REPLACE_EXISTING , &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Name Error (%s)\n", err.message);
    dbus_error_free(&err);
    }
    if (DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER != ret) {
    exit(1);
    }

    // create a new method call and check for errors
    msg = dbus_message_new_method_call("test.method.server", // target for the method call
    "/test/method/Object", // object to call on
    "test.method.Type", // interface to call on
    "Method"); // method name
    if (NULL == msg) {
    fprintf(stderr, "Message Null\n");
    exit(1);
    }

    // append arguments
    dbus_message_iter_init_append(msg, &args);
    if (!dbus_message_iter_append_basic(&args, DBUS_TYPE_STRING, &param)) {
    fprintf(stderr, "Out Of Memory!\n");
    exit(1);
    }

    // send message and get a handle for a reply
    if (!dbus_connection_send_with_reply (conn, msg, &pending, -1)) { // -1 is default timeout
    fprintf(stderr, "Out Of Memory!\n");
    exit(1);
    }
    if (NULL == pending) {
    fprintf(stderr, "Pending Call Null\n");
    exit(1);
    }
    dbus_connection_flush(conn);

    printf("Request Sent\n");

    // free message
    dbus_message_unref(msg);

    // block until we recieve a reply
    dbus_pending_call_block(pending);

    // get the reply message
    msg = dbus_pending_call_steal_reply(pending);
    if (NULL == msg) {
    fprintf(stderr, "Reply Null\n");
    exit(1);
    }
    // free the pending message handle
    dbus_pending_call_unref(pending);

    // read the parameters
    if (!dbus_message_iter_init(msg, &args))
    fprintf(stderr, "Message has no arguments!\n");
    else if (DBUS_TYPE_BOOLEAN != dbus_message_iter_get_arg_type(&args))
    fprintf(stderr, "Argument is not boolean!\n");
    else
    dbus_message_iter_get_basic(&args, &stat);

    if (!dbus_message_iter_next(&args))
    fprintf(stderr, "Message has too few arguments!\n");
    else if (DBUS_TYPE_UINT32 != dbus_message_iter_get_arg_type(&args))
    fprintf(stderr, "Argument is not int!\n");
    else
    dbus_message_iter_get_basic(&args, &level);

    printf("Got Reply: %d, %d\n", stat, level);

    // free reply and close connection
    dbus_message_unref(msg);
    dbus_connection_close(conn);
    }

    void reply_to_method_call(DBusMessage* msg, DBusConnection* conn)
    {
    DBusMessage* reply;
    DBusMessageIter args;
    bool stat = true;
    dbus_uint32_t level = 21614;
    dbus_uint32_t serial = 0;
    char* param = "";

    // read the arguments
    if (!dbus_message_iter_init(msg, &args))
    fprintf(stderr, "Message has no arguments!\n");
    else if (DBUS_TYPE_STRING != dbus_message_iter_get_arg_type(&args))
    fprintf(stderr, "Argument is not string!\n");
    else
    dbus_message_iter_get_basic(&args, &param);

    printf("Method called with %s\n", param);

    // create a reply from the message
    reply = dbus_message_new_method_return(msg);

    // add the arguments to the reply
    dbus_message_iter_init_append(reply, &args);
    if (!dbus_message_iter_append_basic(&args, DBUS_TYPE_BOOLEAN, &stat)) {
    fprintf(stderr, "Out Of Memory!\n");
    exit(1);
    }
    if (!dbus_message_iter_append_basic(&args, DBUS_TYPE_UINT32, &level)) {
    fprintf(stderr, "Out Of Memory!\n");
    exit(1);
    }

    // send the reply && flush the connection
    if (!dbus_connection_send(conn, reply, &serial)) {
    fprintf(stderr, "Out Of Memory!\n");
    exit(1);
    }
    dbus_connection_flush(conn);

    // free the reply
    dbus_message_unref(reply);
    }

    /**
    * Server that exposes a method call and waits for it to be called
    */
    void listen()
    {
    DBusMessage* msg;
    DBusMessage* reply;
    DBusMessageIter args;
    DBusConnection* conn;
    DBusError err;
    int ret;
    char* param;

    printf("Listening for method calls\n");

    // initialise the error
    dbus_error_init(&err);

    // connect to the bus and check for errors
    conn = dbus_bus_get(DBUS_BUS_SYSTEM, &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Connection Error (%s)\n", err.message);
    dbus_error_free(&err);
    }
    if (NULL == conn) {
    fprintf(stderr, "Connection Null\n");
    exit(1);
    }

    // request our name on the bus and check for errors
    ret = dbus_bus_request_name(conn, "test.method.server", DBUS_NAME_FLAG_REPLACE_EXISTING , &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Name Error (%s)\n", err.message);
    dbus_error_free(&err);
    }
    if (DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER != ret) {
    fprintf(stderr, "Not Primary Owner (%d)\n", ret);
    exit(1);
    }

    // loop, testing for new messages
    while (true) {
    // non blocking read of the next available message
    dbus_connection_read_write(conn, 0);
    msg = dbus_connection_pop_message(conn);

    // loop again if we haven't got a message
    if (NULL == msg) {
    sleep(1);
    continue;
    }

    // check this is a method call for the right interface & method
    if (dbus_message_is_method_call(msg, "test.method.Type", "Method"))
    reply_to_method_call(msg, conn);

    // free the message
    dbus_message_unref(msg);
    }

    // close the connection
    dbus_connection_close(conn);
    }

    /**
    * Listens for signals on the bus
    */
    void receive()
    {
    DBusMessage* msg;
    DBusMessageIter args;
    DBusConnection* conn;
    DBusError err;
    int ret;
    char* sigvalue;

    printf("Listening for signals\n");

    // initialise the errors
    dbus_error_init(&err);

    // connect to the bus and check for errors
    conn = dbus_bus_get(DBUS_BUS_SYSTEM, &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Connection Error (%s)\n", err.message);
    dbus_error_free(&err);
    }
    if (NULL == conn) {
    exit(1);
    }

    // request our name on the bus and check for errors
    ret = dbus_bus_request_name(conn, "test.signal.sink", DBUS_NAME_FLAG_REPLACE_EXISTING , &err);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Name Error (%s)\n", err.message);
    dbus_error_free(&err);
    }
    if (DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER != ret) {
    exit(1);
    }

    // add a rule for which messages we want to see
    dbus_bus_add_match(conn, "type='signal',interface='test.signal.Type'", &err); // see signals from the given interface
    dbus_connection_flush(conn);
    if (dbus_error_is_set(&err)) {
    fprintf(stderr, "Match Error (%s)\n", err.message);
    exit(1);
    }
    printf("Match rule sent\n");

    // loop listening for signals being emmitted
    while (true) {

    // non blocking read of the next available message
    dbus_connection_read_write(conn, 0);
    msg = dbus_connection_pop_message(conn);

    // loop again if we haven't read a message
    if (NULL == msg) {
    sleep(1);
    continue;
    }

    // check if the message is a signal from the correct interface and with the correct name
    if (dbus_message_is_signal(msg, "test.signal.Type", "Test")) {

    // read the parameters
    if (!dbus_message_iter_init(msg, &args))
    fprintf(stderr, "Message Has No Parameters\n");
    else if (DBUS_TYPE_STRING != dbus_message_iter_get_arg_type(&args))
    fprintf(stderr, "Argument is not string!\n");
    else
    dbus_message_iter_get_basic(&args, &sigvalue);

    printf("Got Signal with value %s\n", sigvalue);
    }

    // free the message
    dbus_message_unref(msg);
    }
    // close the connection
    dbus_connection_close(conn);
    }

    int main(int argc, char** argv)
    {
    if (2 > argc) {
    printf ("Syntax: dbus-example [send|receive|listen|query] [<param>]\n");
    return 1;
    }
    char* param = "no param";
    if (3 >= argc && NULL != argv[2]) param = argv[2];
    if (0 == strcmp(argv[1], "send"))
    sendsignal(param);
    else if (0 == strcmp(argv[1], "receive"))
    receive();
    else if (0 == strcmp(argv[1], "listen"))
    listen();
    else if (0 == strcmp(argv[1], "query"))
    query(param);
    else {
    printf ("Syntax: dbus-example [send|receive|listen|query] [<param>]\n");
    return 1;
    }
    return 0;
    }