mcs/class/Mono.Management/Mono.Attach/VirtualMachine.cs

   1 using System;
   2 using System.Collections.Generic;
   3 using System.Diagnostics;
   4 using System.Runtime.InteropServices;
   5 using System.Text;
   6 using System.IO;
   7 using System.Threading;
   8 using System.Net;
   9 using System.Net.Sockets;
  10
  11 using Mono.Unix;
  12 using Mono.Unix.Native;
  13
  14 namespace Mono.Attach
  15 {
  16         /*
  17          * Represents a running mono virtual machine.
  18          */
  19         public class VirtualMachine {
  20
  21                 long pid;
  22
  23                 public VirtualMachine (long pid) {
  24                         // FIXME: Check for unix
  25                         this.pid = pid;
  26                 }
  27
  28                 public long Pid {
  29                         get {
  30                                 return pid;
  31                         }
  32                 }
  33
  34                 public bool IsCurrent {
  35                         get {
  36                                 return pid == Syscall.getpid ();
  37                         }
  38                 }
  39
  40                 public string[] GetCommandLine () {
  41                         return File.OpenText ("/proc/" + pid + "/cmdline").ReadToEnd ().Split ('\0');
  42                 }
  43
  44                 public string GetWorkingDirectory () {
  45                         int len = 256;
  46
  47                         while (true) {
  48                                 StringBuilder sb = new StringBuilder (len);
  49
  50                                 int res = Syscall.readlink ("/proc/" + pid + "/cwd", sb);
  51                                 if (res == -1)
  52                                         throw new IOException ("Syscall.readlink () failed with error " + res + ".");
  53                                 else if (res == len) {
  54                                         len = len * 2;
  55                                 } else {
  56                                         return sb.ToString ();
  57                                 }
  58                         }
  59                 }
  60
  61                 /*
  62                  * Return the list of running mono vms owned by the current user. The
  63                  * result includes the current vm too.
  64                  */
  65                 public static List<VirtualMachine> GetVirtualMachines () {
  66                         PerformanceCounterCategory p = new PerformanceCounterCategory (".NET CLR JIT");
  67                         string[] machines = p.GetInstanceNames ();
  68
  69                         var res = new List<VirtualMachine> ();
  70
  71                         foreach (string s in machines) {
  72                                 // The names are in the form 'pid/name'
  73                                 int pos = s.IndexOf ('/');
  74                                 if (pos != -1)
  75                                         res.Add (new VirtualMachine (Int32.Parse (s.Substring (0, pos))));
  76                         }
  77                         return res;
  78                 }
  79
  80                 /*
  81                  * Loads the specific agent assembly into this vm.
  82                  */
  83                 public void Attach (string agent, string args) {
  84                         string user = UnixUserInfo.GetRealUser ().UserName;
  85
  86                         // Check whenever the attach socket exists
  87                         string socket_file = "/tmp/mono-" + user + "/.mono-" + pid;
  88
  89                         if (!File.Exists (socket_file)) {
  90                                 string trigger_file = "/tmp/.mono_attach_pid" + pid;
  91                                 FileStream trigger = null;
  92
  93                                 try {
  94                                         trigger = File.Create (trigger_file);
  95                                         trigger.Close ();
  96
  97                                         // Ask the vm to start the attach mechanism
  98                                         Syscall.kill ((int)pid, Signum.SIGQUIT);
  99
 100                                         // Wait for the socket file to materialize
 101                                         int i;
 102                                         for (i = 0; i < 10; ++i) {
 103                                                 if (File.Exists (socket_file))
 104                                                         break;
 105                                                 Thread.Sleep (100);
 106                                         }
 107
 108                                         if (i == 10)
 109                                                 throw new Exception (String.Format ("Runtime failed to create attach socket '{0}'.", socket_file));
 110                                 } finally {
 111                                         File.Delete (trigger_file);
 112                                 }
 113                         }
 114
 115                         /*
 116                          * We communicate with the agent inside the runtime using a simlified
 117                          * version of the .net remoting protocol.
 118                          */
 119
 120                         string path = "/tmp/mono-" + user + "/.mono-" + pid;
 121
 122                         UnixClient client = new UnixClient (path);
 123
 124                         NetworkStream stream = client.GetStream ();
 125
 126                         // Compose payload
 127                         MemoryStream ms = new MemoryStream ();
 128                         BinaryWriter writer = new BinaryWriter (ms);
 129                         write_string (writer, "attach");
 130                         write_string (writer, agent);
 131                         write_string (writer, args);
 132
 133                         // Write header
 134                         byte[] magic = new byte [] { (byte)'M', (byte)'O', (byte)'N', (byte)'O', 1, 0 };
 135                         stream.Write (magic, 0, magic.Length);
 136
 137                         // Write payload length
 138                         new BinaryWriter (stream).Write ((int)ms.Length);
 139
 140                         // Write payload
 141                         stream.Write (ms.GetBuffer (), 0, (int)ms.Length);
 142                 }
 143
 144                 enum PrimitiveType : byte {
 145                         PRIM_TYPE_NULL = 17,
 146                         PRIM_TYPE_STRING = 18
 147                 };
 148
 149                 void write_string (BinaryWriter writer, string s) {
 150                         if (s == null)
 151                                 writer.Write ((sbyte)PrimitiveType.PRIM_TYPE_NULL);
 152                         else {
 153                                 writer.Write ((sbyte)PrimitiveType.PRIM_TYPE_STRING);
 154                                 writer.Write (s);
 155                         }
 156                 }
 157
 158                 public override string ToString () {
 159                         return "VirtualMachine (pid=" + pid + ")";
 160                 }
 161         }
 162 }