checkpoint debugging of stream buffer.

io/CStreamBuffer.cpp

@@ -38,64 +38,84 @@ const void*				CStreamBuffer::peek(UInt32 n)
 
 void					CStreamBuffer::pop(UInt32 n)
 {
+	// discard all chunks if n is greater than or equal to m_size
+	if (n >= m_size) {
+		m_size = 0;
+		m_chunks.clear();
+		return;
+	}
+
+	// update size
 	m_size -= n;
 
 	// discard chunks until more than n bytes would've been discarded
 	ChunkList::iterator scan = m_chunks.begin();
-	while (scan->size() <= n && scan != m_chunks.end()) {
+	assert(scan != m_chunks.end());
+	while (scan->size() <= n) {
 		n   -= scan->size();
 		scan = m_chunks.erase(scan);
+		assert(scan != m_chunks.end());
 	}
+	assert(n > 0);
 
-	// if there's anything left over then remove it from the head chunk.
+	// remove left over bytes from the head chunk
-	// if there's no head chunk then we're already empty.
-	if (scan == m_chunks.end()) {
-		m_size = 0;
-	}
-	else if (n > 0) {
 	scan->erase(scan->begin(), scan->begin() + n);
 }
-}
 
+#include "CLog.h"
 void					CStreamBuffer::write(
 								const void* vdata, UInt32 n)
 {
 	assert(vdata != NULL);
 
+	// ignore if no data, otherwise update size
 	if (n == 0) {
 		return;
 	}
+log((CLOG_DEBUG "### %p buffering %d bytes onto %d bytes", this, n, m_size));
 	m_size += n;
 
 	// cast data to bytes
 	const UInt8* data = reinterpret_cast<const UInt8*>(vdata);
+if (n > 1000)
+log((CLOG_DEBUG "### %p src: %u %u %u %u %u %u %u %u", this,
+data[0], data[1], data[2], data[3], data[4], data[5], data[6], data[7]));
 
 	// point to last chunk if it has space, otherwise append an empty chunk
 	ChunkList::iterator scan = m_chunks.end();
 	if (scan != m_chunks.begin()) {
+log((CLOG_DEBUG "### %p at least one chunk", this));
 		--scan;
 		if (scan->size() >= kChunkSize)
+{
+log((CLOG_DEBUG "### %p last chunk full", this));
 			++scan;
+}
 	}
 	if (scan == m_chunks.end()) {
-		scan = m_chunks.insert(scan);
+log((CLOG_DEBUG "### %p append chunk", this));
+		scan = m_chunks.insert(scan, Chunk());
 	}
 
 	// append data in chunks
 	while (n > 0) {
 		// choose number of bytes for next chunk
+		assert(scan->size() <= kChunkSize);
 		UInt32 count = kChunkSize - scan->size();
 		if (count > n)
 			count = n;
 
 		// transfer data
+log((CLOG_DEBUG "### %p append %d bytes onto last chunk", this, count));
 		scan->insert(scan->end(), data, data + count);
 		n    -= count;
 		data += count;
 
 		// append another empty chunk if we're not done yet
 		if (n > 0) {
-			scan = m_chunks.insert(scan);
+			++scan;
+			scan = m_chunks.insert(scan, Chunk());
+log((CLOG_DEBUG "### %p append chunk2", this));
 		}
 	}
 }