* Applied a patch from josef that cleand up the chunks seen window.

* More work on rarity-first chunk selection.


git-svn-id: svn://rakshasa.no/libtorrent/trunk/rtorrent@657 e378c898-3ddf-0310-93e7-cc216c733640

src/core/download.cc

@@ -217,6 +217,28 @@ Download::priority_to_string(uint32_t p) {
   }
 }
 
+float
+Download::distributed_copies() const {
+  const uint8_t* avail = m_download.chunks_seen();
+  const uint8_t* end = avail + m_download.chunks_total();
+
+  if (avail == NULL)
+    return 0;
+
+  int minAvail = std::numeric_limits<uint8_t>::max();
+  int num = 0;
+
+  for (; avail < end; ++avail)
+    if (*avail == minAvail) {
+      num++;
+    } else if (*avail < minAvail) {
+      minAvail = *avail;
+      num = 1;
+    }
+
+  return minAvail + 1 - (float)num / m_download.chunks_total();
+}
+
 void
 Download::receive_chunk_failed(__UNUSED uint32_t idx) {
   m_chunksFailed++;

src/core/download.h

@@ -95,6 +95,8 @@ public:
   static uint32_t    string_to_priority(const std::string& name);
   static const char* priority_to_string(uint32_t p);
 
+  float              distributed_copies() const;
+
 private:
   Download(const Download&);
   void operator () (const Download&);