virt-viewer源码分析

本文主要是针对spice的基础上对virt-viewer进行分析，使用这款软件的主要命令就是remote-viewer这个命令，因此本文在此主要分析的文件就是remote-viewer-main.c文件，spice编程方式基本上都是使用c语言实现面向对象的编程方式
安装好软件后使用remote-viewer命令,然后在对话框中的输入：spice://172.16.1.134?port=9004;

然后点击连接就会链接到服务器端了实现远程登录，如下图所示:

 
#include <config.h>//主要是程序中的一些开关的定义，通过#define 来定义实现某些功能的裁剪，这个文件在virt-viewer源码下
#include <locale.h>
#include <gtk/gtk.h>
#include <glib/gi18n.h>
#include <stdlib.h>
#ifdef G_OS_WIN32
#include <windows.h>
#include <io.h>
#endif

#ifdef HAVE_GTK_VNC
#include <vncdisplay.h>
#endif
#ifdef HAVE_SPICE_GTK   //spice-gtk的使能在config.h中
#include <spice-option.h>//主要调用spice的操作选项spice_set_session_option这个函数 设置spice session选项，一些功能的使能，比如usbredir
#endif
#ifdef HAVE_OVIRT
#include <govirt/ovirt-options.h>
#endif

#include "remote-viewer.h"
#include "virt-viewer-app.h"
#include "virt-viewer-session.h"

static void
remote_viewer_version(void)//显示本系统版本好，在config.h中是有定义的，本文件是2.0 版本
{
    g_print(_("remote-viewer version %s\n"), VERSION BUILDID);
    exit(EXIT_SUCCESS);
}

static void
recent_add(gchar *uri, const gchar *mime_type)
{
    GtkRecentManager *recent;
    GtkRecentData meta = {
        .app_name     = (char*)"remote-viewer",
        .app_exec     = (char*)"remote-viewer %u",
        .mime_type    = (char*)mime_type,
    };

    if (uri == NULL)
        return;

    recent = gtk_recent_manager_get_default();
    meta.display_name = uri;
    if (!gtk_recent_manager_add_full(recent, uri, &meta))
        g_warning("Recent item couldn't be added");
}

static void connected(VirtViewerSession *session,
                      VirtViewerApp *self G_GNUC_UNUSED)
{
    gchar *uri = virt_viewer_session_get_uri(session);
    const gchar *mime = virt_viewer_session_mime_type(session);

    recent_add(uri, mime);
    g_free(uri);
}

int
main(int argc, char **argv)
{
    GOptionContext *context;//这是glib中对输入参数的解析，并没有直接利用判断
    GError *error = NULL;
    int ret = 1;
    gchar **args = NULL;
    gchar *uri = NULL;
    char *title = NULL;
    RemoteViewer *viewer = NULL;
#ifdef HAVE_SPICE_GTK //同样检测spice-gtk的时能情况,在config.h中有定义
    gboolean controller = FALSE;//关闭controller
#endif
    VirtViewerApp *app;
    const GOptionEntry options [] = {//GOptionEntry就是GLib提供一个方便我们设置输入参数的结构的，例如 cd /home
        { "version", 'V', G_OPTION_FLAG_NO_ARG, G_OPTION_ARG_CALLBACK,
          remote_viewer_version, N_("Display version information"), NULL },//显示参数-V的作用即 virt-viewer -V,显示相关的信息
        { "title", 't', 0, G_OPTION_ARG_STRING, &title,
          N_("Set window title"), NULL },
#ifdef HAVE_SPICE_GTK
        { "spice-controller", '\0', 0, G_OPTION_ARG_NONE, &controller,
          N_("Open connection using Spice controller communication"), NULL },
#endif
        { G_OPTION_REMAINING, '\0', 0, G_OPTION_ARG_STRING_ARRAY, &args,
          NULL, "URI|VV-FILE" },
        { NULL, 0, 0, G_OPTION_ARG_NONE, NULL, NULL, NULL }
    };
    GOptionGroup *app_options = NULL;

    virt_viewer_util_init(_("Remote Viewer"));//初始化相关的remote选项

    /* Setup command line options */
    context = g_option_context_new (NULL);//重设命令行
    g_option_context_set_summary(context, _("Remote viewer client"));
    app_options = virt_viewer_app_get_option_group();
    g_option_group_add_entries (app_options, options);
    g_option_context_set_main_group (context, app_options);
    g_option_context_add_group (context, gtk_get_option_group (TRUE));
#ifdef HAVE_GTK_VNC
    g_option_context_add_group (context, vnc_display_get_option_group ());
#endif
#ifdef HAVE_SPICE_GTK
    g_option_context_add_group (context, spice_get_option_group ());
#endif
#ifdef HAVE_OVIRT
    g_option_context_add_group (context, ovirt_get_option_group ());
#endif
    g_option_context_parse (context, &argc, &argv, &error);//获取context内的参数
    if (error) {
        char *base_name;
        base_name = g_path_get_basename(argv[0]);
        g_printerr(_("%s\nRun '%s --help' to see a full list of available command line options\n"),
                   error->message, base_name);
        g_free(base_name);
        g_error_free(error);
        goto cleanup;
    }

    g_option_context_free(context);

#ifdef HAVE_SPICE_GTK
    if (controller) {
        if (args) {
            g_printerr(_("Error: extra arguments given while using Spice controller\n"));
            goto cleanup;
        }
    } else
#endif
    if (args) {
        if (g_strv_length(args) > 1) {
            g_printerr(_("Error: can't handle multiple URIs\n"));
            goto cleanup;
        } else if (g_strv_length(args) == 1) {
            uri = g_strdup(args[0]);
        }
    }

#ifdef HAVE_SPICE_GTK
    if (controller) {
        viewer = remote_viewer_new_with_controller();
        g_object_set(viewer, "guest-name", "defined by Spice controller", NULL);
    } else {
#endif
        viewer = remote_viewer_new(uri);
        if (title)
            g_object_set(viewer, "title", title, NULL);
#ifdef HAVE_SPICE_GTK
    }
#endif
    if (viewer == NULL)
        goto cleanup;

    app = VIRT_VIEWER_APP(viewer);

    if (!virt_viewer_app_start(app))
        goto cleanup;

    g_signal_connect(virt_viewer_app_get_session(app), "session-connected",
                     G_CALLBACK(connected), app);

    gtk_main();

    ret = 0;

 cleanup:
    g_free(uri);
    if (viewer)
        g_object_unref(viewer);
    g_strfreev(args);

    return ret;
}