Initial community commit

Src/nu/ProgressTracker.h

@@ -0,0 +1,125 @@
+#include <map>
+#include "AutoLock.h"
+#include <bfc/platform/types.h>
+
+class ProgressTracker
+{
+public:
+	static const uint64_t null_position;
+	ProgressTracker()
+	{
+		current_position=0;
+		current_chunk=0;
+		chunks[0]=0;
+		chunks[null_position]=null_position;
+	};
+
+	void Write(uint64_t bytes_written)
+	{
+		Nullsoft::Utility::AutoLock list_lock(list_guard);
+		ChunkList::iterator next, itr = chunks.find(current_chunk);
+		current_position += bytes_written;
+		if (itr->second < current_position)
+			itr->second = current_position;
+
+		for (;;)
+		{
+			next = itr;
+			++next;
+			if (next != chunks.end() && (next->first <= itr->second))
+			{
+				itr->second = next->second;
+				chunks.erase(next);
+			}
+			else
+				break;
+		}
+	}
+
+	bool Valid(uint64_t requested_position, uint64_t requested_end)
+	{
+		Nullsoft::Utility::AutoLock list_lock(list_guard);
+		for (ChunkList::iterator itr=chunks.begin();itr!=chunks.end();itr++)
+		{
+			if (requested_position >= itr->first)
+			{
+				if (requested_position < itr->second)
+				{
+					if (requested_end <= itr->second)
+					{
+						return true;
+					}
+					else
+					{
+						return false;
+					}
+				}
+			}
+		}
+		return false;
+	}
+
+	bool Seek(uint64_t requested_position, uint64_t requested_end, uint64_t *new_start, uint64_t *new_end)
+	{
+		Nullsoft::Utility::AutoLock list_lock(list_guard);
+		uint64_t last_good_start=0;
+		ChunkList::iterator itr;
+		for (itr=chunks.begin();itr!=chunks.end();itr++)
+		{
+			if (requested_position >= itr->first)
+			{
+				current_chunk = itr->first;
+				if (requested_position <= itr->second)
+				{
+					ChunkList::iterator next = itr;
+					++next;
+					*new_end = next->first;
+
+					*new_start = current_position = itr->second;
+
+					if (requested_end <= itr->second)
+					{
+						return true;
+					}
+					else
+					{
+						return false;
+					}
+				}
+				else
+				{
+					last_good_start = itr->second;
+				}
+			}
+		}
+		if (last_good_start > requested_position)
+			*new_start = current_position = last_good_start;
+		else
+		{
+			
+			*new_start = current_chunk = current_position = requested_position;
+			chunks[current_chunk] = current_chunk;
+		}
+		*new_end = null_position;
+		return false;
+	}
+
+#if 0
+	void Dump()
+	{
+				ChunkList::iterator itr;
+		for (itr=chunks.begin();itr!=chunks.end();itr++)
+		{
+			printf("%I64u - %I64u\n", itr->first, itr->second);
+		}
+
+	}
+	#endif
+
+	typedef std::map<uint64_t, uint64_t> ChunkList;
+	ChunkList chunks;
+	uint64_t current_chunk;
+	uint64_t current_position;
+	Nullsoft::Utility::LockGuard list_guard;
+};
+const uint64_t ProgressTracker::null_position = (uint64_t)-1;