从Go程序中读取媒体密钥

我正在编写媒体跨平台的分布式媒体播放器，以便在我自己的networking上使用。

目前的版本有三个/四个部分：

一个持有audio文件的NAS

包含有关文件信息的元数据服务器。

允许操作元数据服务器和排队媒体的HTML / JS客户机：

一个玩家deamon。

我的问题在于第4部分。玩家没有UI，也不需要UI。 它将通过来自客户端的networking命令和监听当前主机上的媒体密钥来控制。

玩家守护进程需要在Windows和Linux上工作，但我似乎无法找出任何方式（任何方式）在任何一个操作系统上读取这些密钥。 大部分我知道阅读键盘的方法都不会读取这些键。

Cygwin命令在cmd上的彩色输出

最简单的方法来安装Python 3.3.6？ （没有构build）

如何远程注销用户？

真的有办法唯一地识别任何电脑

选项卡控制 – 更改为不同的forms（C＃）

在Windows上安装Python 2.x和3.x时使用较旧的Python 2.x

Vista中的sed – 如何删除之间的所有符号？

使用BinaryReader读取大文件（> 1 GB）时，最佳缓冲区大小是多less？

如何从base64编码的string创build临时文件？

C ++：将__int64转换为无符号长整型

在几位评论员的帮助下，我现在已经明白了。

Linux版本如下：

package main import ( “bytes” “encoding/binary” “fmt” “os” “os/exec” “syscall” ) // parses through the /proc/bus/input/devices file for keyboard devices. // copied from `github.com/gearmover/keylogger` with trivial modification. func dumpDevices() ([]string,error) { cmd := exec.Command(“/bin/sh”,“-c”,“/bin/grep -E 'Handlers|EV=' /proc/bus/input/devices | /bin/grep -B1 'EV=120013' | /bin/grep -Eo 'event[0-9]+'”) output,err := cmd.Output() if err != nil { return nil,err } buf := bytes.NewBuffer(output) var devices []string for line,err := buf.ReadString('n'); err == nil; { devices = append(devices,“/dev/input/”+line[:len(line)-1]) line,err = buf.ReadString('n') } return devices,nil } // Using MS names,just because I don't feel like looking up the Linux versions. var keys = map[uint16]string{ 0xa3: “VK_MEDIA_NEXT_TRACK”,0xa5: “VK_MEDIA_PREV_TRACK”,0xa6: “VK_MEDIA_STOP”,0xa4: “VK_MEDIA_PLAY_PAUSE”,} // Most of the code here comes from `github.com/gearmover/keylogger`. func main() { // drop privileges when executing other programs syscall.Setgid(65534) syscall.Setuid(65534) // dump our keyboard devices from /proc/bus/input/devices devices,err := dumpDevices() if err != nil { fmt.Println(err) } if len(devices) == 0 { fmt.Println(“No input devices found”) return } // bring back our root privs syscall.Setgid(0) syscall.Setuid(0) // Open the first keyboard device. input,err := os.OpenFile(devices[0],os.O_RDONLY,0600) if err != nil { fmt.Println(err) return } defer input.Close() // Log media keys var buffer = make([]byte,24) for { // read the input events as they come in n,err := input.Read(buffer) if err != nil { return } if n != 24 { fmt.Println(“Weird Input Event Size: “,n) continue } // parse the input event according to the <linux/input.h> header struct binary.LittleEndian.Uint64(buffer[0:8]) // Time stamp stuff I Could care less about binary.LittleEndian.Uint64(buffer[8:16]) etype := binary.LittleEndian.Uint16(buffer[16:18]) // Event Type. Always 1 for keyboard events code := binary.LittleEndian.Uint16(buffer[18:20]) // Key scan code value := int32(binary.LittleEndian.Uint32(buffer[20:24])) // press(1),release(0),or repeat(2) if etype == 1 && value == 1 && keys[code] != “” { // In a real application I would send a message here. fmt.Println(keys[code]) } } }

和Windows版本：

package main import ( “fmt” “syscall” “time” ) var user32 = syscall.NewLazyDLL(“user32.dll”) var procgAKS = user32.NewProc(“GetAsyncKeyState”) // Key codes from MSDN var keys = [4]uint{ 0xb0,// VK_MEDIA_NEXT_TRACK 0xb1,// VK_MEDIA_PREV_TRACK 0xb2,// VK_MEDIA_STOP 0xb3,// VK_MEDIA_PLAY_PAUSE } var names = [4]string{ “VK_MEDIA_NEXT_TRACK”,“VK_MEDIA_PREV_TRACK”,“VK_MEDIA_STOP”,“VK_MEDIA_PLAY_PAUSE”,} func main() { fmt.Println(“Running…”) // Since I don't want to trigger dozens of times for each key I need to track state. // I Could check the bits of GAKS' return value,but that is not reliable. down := [4]bool{false,false,false} for { time.Sleep(1 * time.Millisecond) for i,key := range keys { // val is not a simple boolean! // 0 means “not pressed” (also certain errors) // If LSB is set the key was just pressed (this may not be reliable) // If MSB is set the key is currently down. val,_,_ := procgAKS.Call(uintptr(key)) // Turn a press into a transition and track key state. goingdown := false if int(val) != 0 && !down[i] { goingdown = true down[i] = true } if int(val) == 0 && down[i] { down[i] = false } if goingdown { // In a real application I would send a message here. fmt.Println(names[i]) } } } }

唯一的“问题”是Linux版本必须以root身份运行。 对我来说这不是问题。 如果以root身份运行是一个问题，我认为有一种方法涉及X11 …