[thin_show_dups] pull the various streams out to their own files

thin-provisioning/cache_stream.cc

@@ -0,0 +1,91 @@
+#include "thin-provisioning/cache_stream.h"
+#include "persistent-data/file_utils.h"
+
+using namespace thin_provisioning;
+using namespace std;
+using namespace persistent_data;
+
+//----------------------------------------------------------------
+
+namespace {
+	int open_file(string const &path) {
+		int fd = ::open(path.c_str(), O_RDONLY | O_DIRECT | O_EXCL, 0666);
+		if (fd < 0)
+			syscall_failed("open",
+				       "Note: you cannot run this tool with these options on live metadata.");
+
+		return fd;
+	}
+}
+
+//----------------------------------------------------------------
+
+cache_stream::cache_stream(string const &path,
+			   block_address block_size,
+			   size_t cache_mem)
+	: block_size_(block_size),
+	  nr_blocks_(get_nr_blocks(path, block_size)),
+
+	  // hack because cache uses LRU rather than MRU
+	  cache_blocks_((cache_mem / block_size) / 2u),
+	  fd_(open_file(path)),
+	  v_(new bcache::noop_validator()),
+	  cache_(new block_cache(fd_, block_size / 512, nr_blocks_, cache_mem)),
+	  current_index_(0) {
+	load(0);
+	for (block_address i = 1; i < min(cache_blocks_, nr_blocks_); i++)
+		cache_->prefetch(i);
+}
+
+block_address
+cache_stream::nr_chunks() const
+{
+	return nr_blocks_;
+}
+
+void
+cache_stream::rewind()
+{
+	load(0);
+}
+
+bool
+cache_stream::advance(block_address count)
+{
+	if (current_index_ + count >= nr_blocks_)
+		return false;
+
+	current_index_ += count;
+
+	load(current_index_);
+	return true;
+}
+
+block_address
+cache_stream::index() const
+{
+	return current_index_;
+}
+
+chunk const &
+cache_stream::get() const
+{
+	return current_chunk_;
+}
+
+void
+cache_stream::load(block_address b)
+{
+	current_index_ = b;
+	current_block_ = cache_->get(current_index_, 0, v_);
+
+	current_chunk_.offset_sectors_ = (b * block_size_) / 512;
+	current_chunk_.mem_.clear();
+	current_chunk_.mem_.push_back(mem(static_cast<uint8_t *>(current_block_.get_data()),
+					  static_cast<uint8_t *>(current_block_.get_data()) + block_size_));
+
+	if (current_index_ + cache_blocks_ < nr_blocks_)
+		cache_->prefetch(current_index_ + cache_blocks_);
+}
+
+//----------------------------------------------------------------