upmgr.pas

   1 UNIT UPMGR;
   2 {Upload Manager for brodnetd}
   3 {mission:
   4  multiplex uploads thru TC connection
   5   - read files
   6   - add demux info
   7   - add sequence/offset
   8   - handle retransmit requests
   9   - handle all requests
  10   - deprioritize/cancel uploads
  11  keep one TC connection per peer (+expire-delete)
  12  => need 'chat' protocol
  13 }
  14
  15 {to download a file:
  16  - send file request (chat)
  17    (GET channel CHK hash ofset length)
  18    - channel, client choose, reuse
  19  - prepare recv channel
  20  - wait reply (positive/negative)
  21 }
  22
  23 INTERFACE
  24 USES TC;
  25
  26 type tUH = procedure(var tcs:tTCS): of object;
  27 procedure AddUpload(rcpt:tNetAddr; channel:byte; handler:tUH);
  28 {delete with handler=nil}
  29
  30 IMPLEMENTATION
  31
  32 type tPeer_ptr=^tPeer; tPeer=object
  33  tcs: tTCS;
  34  prv: ^tUH; {dynamic array}
  35  prvc: word; {number of allocated items unused are nil}
  36  next:tPeer_ptr;
  37  procedure OnCont;
  38  function AllocChannel:word;
  39 end;
  40 var Peers:^tPeer;
  41
  42 function FindPeer(const addr:tNetAddr): tPeer_ptr;
  43  begin
  44  result:=Peers;
  45  while assigned(result) do begin
  46   if result^.tcs.remote=addr then exit;
  47   result:=result^.next;
  48  end;
  49 end;
  50
  51 procedure AddUpload(rcpt:tNetAddr; channel:byte; handler:tUH);
  52  var peer:^tPeer;
  53  begin
  54  peer:=FindPeer(rcpt);
  55  if not assigned(peer) then begin
  56   New(peer);
  57   peer^.next:=Peers;
  58   peer^.prvc:=channel+1;
  59   peer^.prv:=GetMem(sizeof(peer^.prv)*peer^.prvc);
  60   Peers:=peer;
  61   peer^.tcs.Init(rcpt);
  62   peer^.tcs.CanSend:=@OnCont;
  63  end else begin
  64
  65  end;
  66  if peer^.tcs.txLastSize=0 then peer^.tcs.Start;
  67
  68