minigui:解决gvfb编译报错undefined reference to symbol 'XkbGetIndicatorState'

绝地灬酷狼 2022-05-13 16:44 195阅读 0赞

minigui在linux PC平台创建开发环境时，需要Virtual Frame Buffer 支持(gvfb,qvfb)，minigui官网提供了这两个程序的源码，需要自己下载编译并安装到自己的PC上。

我用的是gvfb,minigui下载地址：[http://www.minigui.org/downloads/gvfb-1.0.0.tar.gz][http_www.minigui.org_downloads_gvfb-1.0.0.tar.gz]

编译安装过程不复杂：  
编译需要cmake支持,如果没有请安装:`sudo apt-get install cmake`  
还需要依赖gtk2.0，如果没有请安装：`sudo apt-get install libgtk2.0-dev`

# 下载
    wget http://www.minigui.org/downloads/gvfb-1.0.0.tar.gz
    # 解包
    tar xvf gvfb-1.0.0.tar.gz
    cd gvfb-1.0.0
    mkdir build
    cd build
    # 生成Makefile
    cmake ..
    # 编译并安装
    sudo make install

然而在编译过程中出错了：

/usr/bin/ld: CMakeFiles/gvfb.dir/gvfb_linux.o: undefined reference to symbol 'XkbGetIndicatorState'

`XkbGetIndicatorState` 是`X11`这个基础库的函数，显然是cmake脚本写得有问题

打开`$gvfb-1.0.0/src/CMakeLists.txt`这个脚本，如下：

SET (PROJECT_NAME gvfb)
    
    LIST (APPEND SRC_LIST
        main.c gvfb_main.c gvfb_view.c gvfb_input.c gvfb_callbacks.c
        gvfb_interface.c gvfb_errmsg.c deviceskin.c skin.c)
    
    IF (WIN32)
        LIST (APPEND SRC_LIST gvfb_win32.c getopt_long.c)
    ELSE ()
        LIST (APPEND SRC_LIST gvfb_linux.c) 
    ENDIF (WIN32)
    
    #pkg-config info
    INCLUDE (FindPkgConfig)
    
    PKG_CHECK_MODULES (GTK gtk+-2.0 gthread-2.0)
    
    IF (NOT GTK_FOUND)
        MESSAGE(FATAL_ERROR "Gtk+-2.0 not found")
    ENDIF (NOT GTK_FOUND)
    
    INCLUDE_DIRECTORIES (${GTK_INCLUDE_DIRS})
    LINK_DIRECTORIES (${CMAKE_LIBRARY_PATH} ${GTK_LIBRARY_DIRS})
    LIST (APPEND linkflags ${GTK_LIBRARIES})
    
    ADD_EXECUTABLE (${PROJECT_NAME} ${SRC_LIST})
    
    TARGET_LINK_LIBRARIES (${PROJECT_NAME} ${linkflags})
    INSTALL (TARGETS ${PROJECT_NAME} RUNTIME DESTINATION bin)

在脚本最后增加一行`message(STATUS linkflags=${linkflags})`输出`linkflags`变量的值，再执行`cmake ..`，可以看出`linkflags`中果然是没有`-lX11`

输出如下:

-- The C compiler identification is GNU 5.4.0
    -- The CXX compiler identification is GNU 5.4.0
    -- Check for working C compiler: /usr/bin/cc
    -- Check for working C compiler: /usr/bin/cc -- works
    -- Detecting C compiler ABI info
    -- Detecting C compiler ABI info - done
    -- Detecting C compile features
    -- Detecting C compile features - done
    -- Check for working CXX compiler: /usr/bin/c++
    -- Check for working CXX compiler: /usr/bin/c++ -- works
    -- Detecting CXX compiler ABI info
    -- Detecting CXX compiler ABI info - done
    -- Detecting CXX compile features
    -- Detecting CXX compile features - done
    -- Found PkgConfig: /usr/bin/pkg-config (found version "0.29.1") 
    -- Checking for modules 'gtk+-2.0;gthread-2.0'
    --   Found gtk+-2.0, version 2.24.30
    --   Found gthread-2.0, version 2.48.2
    -- linkflags=gtk-x11-2.0gdk-x11-2.0pangocairo-1.0atk-1.0cairogdk_pixbuf-2.0gio-2.0pangoft2-1.0pango-1.0gobject-2.0fontconfigfreetypegthread-2.0glib-2.0
    -- Configuring done
    -- Generating done
    -- Build files have been written to: /home/gyd/Downloads/gvfb-1.0.0/build

确定原因解决问题的办法就很简单了,修改`TARGET_LINK_LIBRARIES`这一行，加入`-lX11`,重新执行cmake生成Makefile就解决问题：

TARGET_LINK_LIBRARIES (${PROJECT_NAME} ${linkflags} -lX11)

[http_www.minigui.org_downloads_gvfb-1.0.0.tar.gz]: http://www.minigui.org/downloads/gvfb-1.0.0.tar.gz