versaplexd/vxdbus.cs

   1 using System;
   2 using System.Collections.Generic;
   3 using Wv;
   4
   5 public static class VxDbus {
   6     static WvLog log = new WvLog("VxDbus", WvLog.L.Debug1);
   7     static WvLog smalldump = log.split(WvLog.L.Debug4);
   8     static WvLog fulldump = log.split(WvLog.L.Debug5);
   9
  10     public static Message CreateError(string type, string msg, Message cause)
  11     {
  12         Message error = new Message();
  13         error.Header.MessageType = MessageType.Error;
  14         error.Header.Flags =
  15             HeaderFlag.NoReplyExpected | HeaderFlag.NoAutoStart;
  16         error.Header.Fields[FieldCode.ErrorName] = type;
  17         error.Header.Fields[FieldCode.ReplySerial] = cause.Header.Serial;
  18
  19         object sender;
  20         if (cause.Header.Fields.TryGetValue(FieldCode.Sender, out sender))
  21             error.Header.Fields[FieldCode.Destination] = sender;
  22
  23         if (msg != null) {
  24             error.Signature = new Signature("s");
  25             MessageWriter writer =
  26                 new MessageWriter(Connection.NativeEndianness);
  27             writer.Write(msg);
  28             error.Body = writer.ToArray();
  29         }
  30
  31         return error;
  32     }
  33
  34     public static Message CreateReply(Message call)
  35     {
  36         return CreateReply(call, null, null);
  37     }
  38
  39     public static Message CreateReply(Message call, string signature,
  40             MessageWriter body)
  41     {
  42         Message reply = new Message();
  43         reply.Header.MessageType = MessageType.MethodReturn;
  44         reply.Header.Flags =
  45             HeaderFlag.NoReplyExpected | HeaderFlag.NoAutoStart;
  46         reply.Header.Fields[FieldCode.ReplySerial] = call.Header.Serial;
  47
  48         object sender;
  49         if (call.Header.Fields.TryGetValue(FieldCode.Sender, out sender))
  50             reply.Header.Fields[FieldCode.Destination] = sender;
  51
  52         if (signature != null && signature != "") {
  53             reply.Signature = new Signature(signature);
  54             reply.Body = body.ToArray();
  55         }
  56
  57         return reply;
  58     }
  59
  60     public static Message CreateSignal(object destination, string signalname,
  61                                         string signature, MessageWriter body)
  62     {
  63         // Idea shamelessly stolen from CreateReply method above
  64         Message signal = new Message();
  65         signal.Header.MessageType = MessageType.Signal;
  66         signal.Header.Flags =
  67             HeaderFlag.NoReplyExpected | HeaderFlag.NoAutoStart;
  68         // The ObjectPath is required by signals, and is the "source of the
  69         // signal."  OK then; seems useless to me.
  70         signal.Header.Fields[FieldCode.Path] = new ObjectPath("/db");
  71         signal.Header.Fields[FieldCode.Interface] = "vx.db";
  72         signal.Header.Fields[FieldCode.Member] = signalname;
  73
  74         if (destination != null)
  75             signal.Header.Fields[FieldCode.Destination] = destination;
  76
  77         if (signature != null && signature != "")
  78         {
  79             signal.Signature = new Signature(signature);
  80             signal.Body = body.ToArray();
  81         }
  82
  83         return signal;
  84     }
  85
  86     public static void MessageDump(string prefix, Message msg)
  87     {
  88         Header hdr = msg.Header;
  89
  90         if (hdr.Fields.ContainsKey(FieldCode.ReplySerial))
  91             log.print("MD {0} REPLY#{1}\n",
  92                         prefix,
  93                         hdr.Fields[FieldCode.ReplySerial]);
  94         else if (hdr.MessageType != MessageType.Signal)
  95             log.print("MD {0} #{1} {2}.{3}\n",
  96                         prefix,
  97                         hdr.Serial,
  98                         hdr.Fields[FieldCode.Interface],
  99                         hdr.Fields[FieldCode.Member]);
 100         else
 101             log.print("MD {0} {1}\n", prefix, hdr.Fields[FieldCode.Interface]);
 102
 103         smalldump.print("Message dump:\n");
 104         smalldump.print(" endianness={0} ", hdr.Endianness);
 105         smalldump.print(" t={0} ", hdr.MessageType);
 106         smalldump.print(" ver={0} ", hdr.MajorVersion);
 107         smalldump.print(" blen={0} ", hdr.Length);
 108         smalldump.print(" ser={0}\n", hdr.Serial);
 109         smalldump.print(" flags={0}\n", hdr.Flags);
 110
 111         smalldump.print(" Fields\n");
 112         foreach (KeyValuePair<FieldCode,object> kvp in hdr.Fields) {
 113             smalldump.print("  - {0}: {1}\n", kvp.Key, kvp.Value);
 114         }
 115
 116         int hdrlen = 0;
 117         byte[] header = msg.GetHeaderData();
 118         if (header != null) {
 119             smalldump.print("Header data:\n");
 120             smalldump.print(wv.hexdump(header));
 121             hdrlen = header.Length;
 122         } else {
 123             smalldump.print("No header data encoded\n");
 124         }
 125
 126         if (msg.Body != null) {
 127             fulldump.print("Body data:\n");
 128             fulldump.print(wv.hexdump(msg.Body, hdrlen, msg.Body.Length));
 129         } else {
 130             smalldump.print("No body data encoded\n");
 131         }
 132     }
 133 }
 134
 135 public class VxMethodCallRouter {
 136     WvLog log = new WvLog("VxMethodCallRouter", WvLog.L.Debug3);
 137
 138     private IDictionary<string,VxInterfaceRouter> interfaces
 139         = new Dictionary<string,VxInterfaceRouter>();
 140
 141     public void AddInterface(VxInterfaceRouter ir)
 142     {
 143         log.print("Adding interface {0}\n", ir.Interface);
 144         interfaces.Add(ir.Interface, ir);
 145     }
 146
 147     public void RemoveInterface(VxInterfaceRouter ir)
 148     {
 149         RemoveInterface(ir.Interface);
 150     }
 151
 152     public void RemoveInterface(string iface)
 153     {
 154         interfaces.Remove(iface);
 155     }
 156
 157     public bool RouteMessage(Message call, out Message reply)
 158     {
 159         if (call.Header.MessageType != MessageType.MethodCall)
 160             throw new ArgumentException("Not a method call message");
 161
 162         reply = null;
 163
 164         // FIXME: Dbus spec says that interface should be optional so it
 165         // should search all of the interfaces for a matching method...
 166         object iface;
 167         if (!call.Header.Fields.TryGetValue(FieldCode.Interface, out iface))
 168             return false; // No interface; ignore it
 169
 170         log.print("Router interface {0}\n", iface);
 171
 172         VxInterfaceRouter ir;
 173         if (!interfaces.TryGetValue((string)iface, out ir))
 174             return false; // Interface not found
 175
 176         log.print("Passing to interface router\n");
 177
 178         return ir.RouteMessage(call, out reply);
 179     }
 180 }
 181
 182 public abstract class VxInterfaceRouter {
 183     public readonly string Interface;
 184
 185     protected VxInterfaceRouter(string iface)
 186     {
 187         Interface = iface;
 188     }
 189
 190     // Return value is the response
 191     protected delegate
 192         void MethodCallProcessor(Message call, out Message reply);
 193
 194     protected IDictionary<string,MethodCallProcessor> methods
 195         = new Dictionary<string,MethodCallProcessor>();
 196
 197     public bool RouteMessage(Message call, out Message reply)
 198     {
 199         if (call.Header.MessageType != MessageType.MethodCall)
 200             throw new ArgumentException("Not a method call message");
 201
 202         reply = null;
 203
 204         object method;
 205         if (!call.Header.Fields.TryGetValue(FieldCode.Member, out method))
 206             return false; // No method
 207
 208         MethodCallProcessor processor;
 209         if (!methods.TryGetValue((string)method, out processor)) {
 210             reply = VxDbus.CreateError(
 211                     "org.freedesktop.DBus.Error.UnknownMethod",
 212                     String.Format(
 213                         "Method name {0} not found on interface {1}",
 214                         method, Interface), call);
 215
 216             return true;
 217         }
 218
 219         ExecuteCall(processor, call, out reply);
 220
 221         return true;
 222     }
 223
 224     protected virtual void ExecuteCall(MethodCallProcessor processor,
 225             Message call, out Message reply)
 226     {
 227         try {
 228             processor(call, out reply);
 229         } catch (Exception e) {
 230             reply = VxDbus.CreateError(
 231                     "vx.db.exception",
 232                     e.ToString(), call);
 233         }
 234     }
 235 }