From: victor <victor@e16421f0-f15b-0410-abcd-98678b794739>
Date: Sat, 7 Nov 2009 12:31:50 +0000 (+0000)
Subject: totally twisted
X-Git-Url: http://p2p-next.cs.pub.ro/gitweb/?a=commitdiff_plain;h=9e10683827addcd0776eec859a504c1b18794b8f;p=swift-upb.git

totally twisted

git-svn-id: https://ttuki.vtt.fi/svn/p2p-next/TUD/p2tp/trunk@509 e16421f0-f15b-0410-abcd-98678b794739
---

diff --git a/bin64.h b/bin64.h
index 8ca1d6f..ecc0b9b 100644
--- a/bin64.h
+++ b/bin64.h
@@ -106,6 +106,10 @@ struct bin64_t {
         else
             return right();
     }
+    
+    bin64_t twisted (uint64_t mask) const {
+        return bin64_t( v ^ ((mask<<1)&~tail_bits()) );
+    }
 
     bin64_t parent () const {
         uint64_t tbs = tail_bits(), ntbs = (tbs+1)|tbs;
diff --git a/ext/seq_picker.cpp b/ext/seq_picker.cpp
index 4070b55..c9b4da2 100644
--- a/ext/seq_picker.cpp
+++ b/ext/seq_picker.cpp
@@ -15,17 +15,33 @@ class SeqPiecePicker : public PiecePicker {
     
     bins            ack_hint_out_;
     FileTransfer*   file_;
+    uint64_t        twist_;
     
 public:
     
-    SeqPiecePicker (FileTransfer* file_to_pick_from) : file_(file_to_pick_from), ack_hint_out_() {
+    SeqPiecePicker (FileTransfer* file_to_pick_from) : 
+    file_(file_to_pick_from), ack_hint_out_(), twist_(0) {
         ack_hint_out_.copy_range(file_->ack_out(),bin64_t::ALL);
     }
     
+    virtual void Randomize (uint64_t twist) {
+        twist_ = twist;
+    }
+    
     virtual bin64_t Pick (bins& offer, uint8_t layer) {
-
+        if (twist_) {
+            offer.twist(twist_);
+            ack_hint_out_.twist(twist_);
+        }
         bin64_t hint = offer.find_filtered
-            (ack_hint_out_,bin64_t::ALL,layer,bins::FILLED);
+                (ack_hint_out_,bin64_t::ALL,layer,bins::FILLED);
+        if (twist_) {
+            hint = hint.twisted(twist_);
+            //dprintf("found twisted by %lli fixed to (%i,%lli)\n",
+            //        twist_,hint.layer(),hint.offset());
+            offer.twist(0);
+            ack_hint_out_.twist(0);
+        }
         if (hint==bin64_t::NONE)
             return hint; // TODO: end-game mode
         while (hint.layer()>layer)
diff --git a/p2tp.h b/p2tp.h
index 2e8c8e7..589a7e5 100644
--- a/p2tp.h
+++ b/p2tp.h
@@ -219,6 +219,7 @@ namespace p2tp {
 
     class PiecePicker {
     public:
+        virtual void Randomize (uint64_t twist) = 0;
         virtual bin64_t Pick (bins& offered, uint8_t layer) = 0;
         virtual void    Expired (bin64_t b) = 0;
         virtual void    Received (bin64_t b) = 0;
diff --git a/tests/binstest2.cpp b/tests/binstest2.cpp
index d3f7a81..cb3950c 100755
--- a/tests/binstest2.cpp
+++ b/tests/binstest2.cpp
@@ -295,6 +295,9 @@ TEST(BinsTest,Twist) {
     b.twist(1<<3);
     EXPECT_EQ(bins::FILLED,b.get(bin64_t(3,3)));
     EXPECT_EQ(bins::EMPTY,b.get(bin64_t(3,2)));
+    bin64_t tw = b.find(bin64_t(5,0),3,bins::FILLED);
+    tw = tw.twisted(1<<3);
+    EXPECT_EQ(bin64_t(3,2),tw);
     b.twist(0);
     EXPECT_EQ(bins::FILLED,b.get(bin64_t(3,2)));
     EXPECT_EQ(bins::EMPTY,b.get(bin64_t(3,3)));
diff --git a/tests/transfertest.cpp b/tests/transfertest.cpp
index 334f9a8..432f990 100644
--- a/tests/transfertest.cpp
+++ b/tests/transfertest.cpp
@@ -53,6 +53,7 @@ TEST(TransferTest,TransferFile) {
     unlink("copy");
     FileTransfer::instance = 1;
     FileTransfer* leech = new FileTransfer("copy",seed->root_hash());
+    leech->picker().Randomize(0);
     // transfer peak hashes
     for(int i=0; i<seed->peak_count(); i++)
         leech->OfferHash(seed->peak(i),seed->peak_hash(i));
@@ -70,6 +71,7 @@ TEST(TransferTest,TransferFile) {
             delete leech;
             FileTransfer::instance = 1;
             leech = new FileTransfer("copy",seed->root_hash());
+            leech->picker().Randomize(0);
             EXPECT_EQ(2,leech->complete_kilo());
         }
         bin64_t next = leech->picker().Pick(seed->ack_out(),0);
diff --git a/transfer.cpp b/transfer.cpp
index f0983f4..4e45484 100644
--- a/transfer.cpp
+++ b/transfer.cpp
@@ -44,6 +44,7 @@ FileTransfer::FileTransfer (const char* filename, const Sha1Hash& _root_hash) :
     else
         RecoverProgress();
     picker_ = new SeqPiecePicker(this);
+    picker_->Randomize(Datagram::Time()&7);
 }