近期想要写一个gdbus的demo程序，查阅了一下资料，发现貌似gdbus之间的IPC通信分为两种，一种是基于system总线，一种是基于session，我通过session通信的方式简单写了一个p2p的demo程序。首先通过gdbus-codegen 生成.h 和.c 文件，然后通过glib gio的接口分别写了一个客户端和服务端，客户端通过method与服务端进行同步通信，服务端通过signal 主动向客户端发送信号通知。服务端流程图如下
客户端流程图如下
程序使用automake进行构建，结构如下
<code>├── autogen.sh├── configure.ac├── LICENSE├── Makefile.am├── private-include│ ├── common.h│ ├── gdbus_client.h│ └── gdbus_server.h├── README.md└── src├── Building.xml├── gdbus_client.c├── gdbus_server.c└── Makefile.am/<code>
下面把各文件的内容贴上
1. Building.xml
<code>
<node>
<interface>
<method>
/<method>
<signal>
/<signal>
/<interface>
/<node>/<code>
method中s代表字符串，i代表数字，其中direction中in代表入参，即发送的值，out代表出参，即获取的值signal代表服务端发送的信号，此处表示发送一个数字
2. Makefile.am
<code>AM_CFLAGS = $(GLIB_CFLAGS) $(GIO_CFLAGS) -g
AM_CPPFLAGS = -I$(top_srcdir)/private-include
BUILT_SOURCES = Building.c Building.h
dist_noinst_DATA = Building.xml
bin_PROGRAMS = gdbus_server gdbus_client
gdbus_server_SOURCES = gdbus_server.c \\
Building.c Building.h
gdbus_server_LDADD = $(GLIB_LIBS) $(GIO_LIBS)
gdbus_client_SOURCES = gdbus_client.c \\
BuildingClient.c BuildingClient.h
gdbus_client_LDADD = $(GLIB_LIBS) $(GIO_LIBS)
Building.c Building.h : Building.xml
gdbus-codegen --interface-prefix=com.qiaotsh.Building --generate-c-code=Building $<
MOSTLYCLEANFILES = $(BUILT_SOURCES)/<code>
Makefile.am中使用gdbus-codegen对Building.xml进行处理，生成Building.h Building.c，
–interface-prefix代表省略前缀名com.qiaotsh.Building,这样在生成文件中将以Test为函数开头，否则字符串看起来比较冗余，是comqiaoBuildingtest开头，目的是增强可读性，–generate-c-code代表生成C语言代码
3. gdbus_client.c
<code>/*
* =====================================================================================
*
* Filename: gdbus_client.c
*
* Description:
*
* Version: 1.0
* Created: 02/17/2017 08:28:34 AM
* Revision: none
* Compiler: gcc
*
* Author: qiaotsh (), [email protected]
* Organization: www.neusoft.com
*
* =====================================================================================
*/
#include <glib.h>
#include/<glib.h>/<code>
#include <unistd.h>
#include "Building.h"
#include "gdbus_client.h"
static gboolean test_status_handler(Test* object,gint status,gpointer user_data){
g_print("signal received %d\\n",status);
return TRUE;
}
static void cb_OwnerNameChangedNotify(GObject *object, GParamSpec *pspec, gpointer userdata){
gchar *pname_owner = NULL;
pname_owner = g_dbus_proxy_get_name_owner((GDBusProxy*)object);
if (NULL != pname_owner){
g_print("DBus service is ready!\\n");
g_free(pname_owner);
}
else{
g_print("DBus service is NOT ready!\\n");
g_free(pname_owner);
}
}
int main(int argc, char *argv[]){
Test *proxy=NULL;
GError *error = NULL;
GMainLoop* loop = NULL;
proxy = test_proxy_new_for_bus_sync (
G_BUS_TYPE_SESSION,
G_DBUS_PROXY_FLAGS_NONE,
"com.qiaotsh.Building.Test",
"/com/qiaotsh/Building/Test",
NULL,
&error);
if(0 == proxy)
{
g_print("InitDBusCommunication: Failed to create proxy. Reason: %s.\\n", error->message);
}
g_signal_connect(proxy,"test-status",G_CALLBACK(test_status_handler),NULL);
char *reply = NULL;
test_call_set_version_sync (proxy, "hello world", &reply,NULL, &error);
g_print("sync reply = %s\\n",reply);
loop = g_main_loop_new(NULL, FALSE);
g_main_loop_run(loop);
g_object_unref(proxy);
return 0;
}/<unistd.h>
值得注意的是test_status_handler的参数不是随便定义的，具体形式在Building.c中有详细描述
4. gdbus_server.c
<code>/*
* =====================================================================================
*
* Filename: gdbus_client.c
*
* Description:
*
* Version: 1.0
* Created: 02/17/2017 08:28:34 AM
* Revision: none
* Compiler: gcc
*
* Author: qiaotsh (), [email protected]
* Organization: www.neusoft.com
*
* =====================================================================================
*/
#include<stdio.h>
#include/<stdio.h>/<code>
#include<glib.h>
#include<assert.h>
#include"Building.h"
#include"gdbus_server.h"
static Test* skeleton=NULL;
static gboolean Emit_Test_Status(gconstpointer p){
g_print("Emit_Test_Status() is called.\\n");
gint status = 5;
test_emit_test_status (skeleton,status);
return TRUE;
}
static gboolean on_handle_set_version(Test* skeleton,
GDBusMethodInvocation *invocation,
const gchar *greeting,
gpointer user_data){
g_print("Method call: %s\\n", greeting);
char* reply = "getSuccess";
test_complete_set_version (skeleton,invocation,reply);
return TRUE;
}
void GBusAcquired_Callback (GDBusConnection *connection,
const gchar *name,
gpointer user_data){
GError *error = NULL;
printf("GBusAcquired_Callback has been invoked\\n");
printf("GBusAcquired_Callback the name = %s\\n",name);
printf("GBusAcquired_Callback the user_data = %s\\n",(char*)user_data);
skeleton = test_skeleton_new ();
g_signal_connect(skeleton,"handle-set-version",G_CALLBACK(on_handle_set_version),NULL);
g_dbus_interface_skeleton_export(G_DBUS_INTERFACE_SKELETON(skeleton), connection, "/com/qiaotsh/Building/Test", &error);
if(error != NULL){
g_print("Error: Failed to export object. Reason: %s.\\n", error->message);
g_error_free(error);
}
}
void GBusNameAcquired_Callback (GDBusConnection *connection,
const gchar *name,
gpointer user_data){
printf("GBusNameAcquired_Callback has been invoked\\n");
}
void GBusNameLost_Callback (GDBusConnection *connection,
const gchar *name,
gpointer user_data){
printf("GBusNameLost_Callback has been invoked\\n");
}
int main(int argc,char* argv[]){
char* s = "qiaotsh";
GMainLoop* loop = NULL;
guint own_id =
g_bus_own_name (G_BUS_TYPE_SESSION,
"com.qiaotsh.Building.Test",
G_BUS_NAME_OWNER_FLAGS_NONE,
GBusAcquired_Callback,
GBusNameAcquired_Callback,
GBusNameLost_Callback,
(gpointer)s,
NULL);
/* * emit my signal1 every 1 second to trigger example communication */
g_timeout_add(1000, (GSourceFunc)Emit_Test_Status, NULL);
loop = g_main_loop_new(NULL, FALSE);
g_main_loop_run(loop);
g_bus_unown_name(own_id);
return 0;
}/<assert.h>/<glib.h>
同理，on_handle_set_version的参数在Building.c中有定义，不可随便定义
5. gdbus_server.h
<code>/*
* =====================================================================================
*
* Filename: gdbus_server.h
*
* Description:
*
* Version: 1.0
* Created: 10/31/2017 10:11:19 AM
* Revision: none
* Compiler: gcc
*
* Author: qiaotsh (), [email protected]
* Organization: www.neusoft.com
*
* =====================================================================================
*/
#ifndef __GDBUS_SERVER_H_
#define __GDBUS_SERVER_H_
#define GDBUS_API __attribute__((visibility("hidden")))
GDBUS_API void GBusAcquired_Callback (GDBusConnection *connection,
const gchar *name,
gpointer user_data);
GDBUS_API void GBusNameAcquired_Callback (GDBusConnection *connection,
const gchar *name,
gpointer user_data);
GDBUS_API void GBusNameLost_Callback (GDBusConnection *connection,
const gchar *name,
gpointer user_data);
#endif/<code>
gdbus_client.h是空的，因为我懒。common.h是空的，没准以后会用上呢
6. autogen.sh
<code>#!/bin/sh
autoreconf --verbose --force --install --make || {
echo 'autogen.sh failed';
exit 1;
}
echo
echo "Now you can 'configure' then 'make'"
echo/<code>
7. configure.ac
<code>AC_INIT([gdbus-example], [0.1], [[email protected]])
AC_CONFIG_AUX_DIR([build-aux])
AC_CONFIG_MACRO_DIR([m4])
AM_INIT_AUTOMAKE([foreign -Wall -Werror])
AM_PROG_AR
LT_INIT
AC_PROG_CC
AC_CONFIG_HEADERS([config.h])
AC_CONFIG_FILES([Makefile src/Makefile ])
PKG_CHECK_MODULES([GLIB], [glib-2.0 >= 2.40.2])
PKG_CHECK_MODULES([GIO], [gio-unix-2.0 >= 2.40.2])
AC_OUTPUT/<code>
8. 编译方法如下
<code>./autogen.sh
./configure $CONFIGURE_FLAGS –prefix=/usr
make
make install/<code>
生成gdbus_server 和gdbus_client
9. 执行效果如下
<code>gdbus_server
GBusAcquired_Callback has been invoked
GBusAcquired_Callback the name = com.qiaotsh.Building.Test
GBusAcquired_Callback the user_data = qiaotsh
GBusNameAcquired_Callback has been invoked
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Method call: hello world
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
Emit_Test_Status() is called.
gdbus_client
sync reply = getSuccess
signal received 5
signal received 5
signal received 5
signal received 5
signal received 5
signal received 5
signal received 5
signal received 5
signal received 5
signal received 5
signal received 5
signal received 5
signal received 5/<code>
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