dump the metadata snap block in the superblock detail

emitter.h

@@ -20,6 +20,7 @@
 #define EMITTER_H
 
 #include <boost/shared_ptr.hpp>
+#include <boost/optional.hpp>
 #include <string>
 #include <stdint.h>
 
@@ -48,7 +49,8 @@ namespace thin_provisioning {
 					      uint64_t time,
 					      uint64_t trans_id,
 					      uint32_t data_block_size,
-					      uint64_t nr_data_blocks) = 0;
+					      uint64_t nr_data_blocks,
+					      boost::optional<uint64_t> metadata_snap) = 0;
 		virtual void end_superblock() = 0;
 
 		virtual void begin_device(uint32_t dev_id,

human_readable_format.cc

@@ -36,13 +36,17 @@ namespace {
 				      uint64_t time,
 				      uint64_t trans_id,
 				      uint32_t data_block_size,
-				      uint64_t nr_data_blocks) {
+				      uint64_t nr_data_blocks,
+				      boost::optional<uint64_t> metadata_snap) {
 			out_ << "begin superblock: \"" << uuid << "\""
 			     << ", " << time
 			     << ", " << trans_id
 			     << ", " << data_block_size
-			     << ", " << nr_data_blocks
+			     << ", " << nr_data_blocks;
-			     << endl;
+			if (metadata_snap)
+				out_ << ", " << metadata_snap;
+
+			out_ << endl;
 		}
 
 		void end_superblock() {

restore_emitter.cc

@@ -39,7 +39,8 @@ namespace {
 					      uint64_t time,
 					      uint64_t trans_id,
 					      uint32_t data_block_size,
-					      uint64_t nr_data_blocks) {
+					      uint64_t nr_data_blocks,
+					      optional<uint64_t> metadata_snap) {
 			in_superblock_ = true;
 
 			superblock &sb = md_->sb_;
@@ -47,6 +48,7 @@ namespace {
 			sb.time_ = time;
 			sb.trans_id_ = trans_id;
 			sb.data_block_size_ = data_block_size;
+			sb.metadata_snap_ = metadata_snap ? *metadata_snap : 0;
 			md_->data_sm_->extend(nr_data_blocks);
 		}
 

thin_dump.cc

@@ -32,10 +32,10 @@ using namespace thin_provisioning;
 
 namespace {
 	int dump(string const &path, string const &format, bool repair,
-		 block_address held_root = 0) {
+		 block_address metadata_snap = 0) {
 		try {
-			metadata::ptr md(held_root ?
+			metadata::ptr md(metadata_snap ?
-					 new metadata(path, held_root) :
+					 new metadata(path, metadata_snap) :
 					 new metadata(path, metadata::OPEN));
 			emitter::ptr e;
 
@@ -64,7 +64,7 @@ namespace {
 		    << "  {-h|--help}" << endl
 		    << "  {-f|--format} {xml|human_readable}" << endl
 		    << "  {-r|--repair}" << endl
-		    << "  {-s|--held-superblock}" << endl
+		    << "  {-m|--metadata-snap}" << endl
 		    << "  {-V|--version}" << endl;
 	}
 }
@@ -73,14 +73,14 @@ int main(int argc, char **argv)
 {
 	int c;
 	bool repair = false;
-	const char shortopts[] = "hs:f:rV";
+	const char shortopts[] = "hm:f:rV";
 	string format = "xml";
-	block_address held_root = 0;
+	block_address metadata_snap = 0;
 	char *end_ptr;
 
 	const struct option longopts[] = {
 		{ "help", no_argument, NULL, 'h'},
-		{ "held-root", required_argument, NULL, 's' },
+		{ "metadata-snap", required_argument, NULL, 'm' },
 		{ "format", required_argument, NULL, 'f' },
 		{ "repair", no_argument, NULL, 'r'},
 		{ "version", no_argument, NULL, 'V'},
@@ -101,17 +101,17 @@ int main(int argc, char **argv)
 			repair = true;
 			break;
 
-		case 's':
+		case 'm':
-			held_root = strtoull(optarg, &end_ptr, 10);
+			metadata_snap = strtoull(optarg, &end_ptr, 10);
 			if (end_ptr == optarg) {
-				cerr << "couldn't parse <held_root>" << endl;
+				cerr << "couldn't parse <metadata_snap>" << endl;
 				usage(cerr, basename(argv[0]));
 				return 1;
 			}
 			break;
 
 		case 'V':
-			cerr << THIN_PROVISIONING_TOOLS_VERSION << endl;
+			cout << THIN_PROVISIONING_TOOLS_VERSION << endl;
 			return 0;
 
 		default:
@@ -126,5 +126,5 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
-	return dump(argv[optind], format, repair, held_root);
+	return dump(argv[optind], format, repair, metadata_snap);
 }

thin_pool.cc

@@ -177,9 +177,9 @@ thin_pool::get_transaction_id() const
 }
 
 block_address
-thin_pool::get_held_root() const
+thin_pool::get_metadata_snap() const
 {
-	return md_->sb_.held_root_;
+	return md_->sb_.metadata_snap_;
 }
 
 block_address

thin_pool.h

@@ -69,7 +69,7 @@ namespace thin_provisioning {
 		void set_transaction_id(uint64_t id);
 		uint64_t get_transaction_id() const;
 
-		block_address get_held_root() const;
+		block_address get_metadata_snap() const;
 
 		block_address alloc_data_block();
 		void free_data_block(block_address b);

xml_format.cc

@@ -19,6 +19,7 @@
 #include "xml_format.h"
 
 #include <boost/lexical_cast.hpp>
+#include <boost/optional.hpp>
 #include <expat.h>
 #include <iostream>
 #include <map>
@@ -49,13 +50,19 @@ namespace {
 				      uint64_t time,
 				      uint64_t trans_id,
 				      uint32_t data_block_size,
-				      uint64_t nr_data_blocks) {
+				      uint64_t nr_data_blocks,
+				      optional<uint64_t> metadata_snap) {
 			indent();
 			out_ << "<superblock uuid=\"" << uuid << "\""
 			     << " time=\"" << time << "\""
 			     << " transaction=\"" << trans_id << "\""
 			     << " data_block_size=\"" << data_block_size << "\""
-			     << " nr_data_blocks=\"" << nr_data_blocks << "\">"
+			     << " nr_data_blocks=\"" << nr_data_blocks;
+
+			if (metadata_snap)
+				out_ << " metadata_snap=\"" << *metadata_snap;
+
+			out_ << "\">"
 			     << endl;
 			inc();
 		}
@@ -174,12 +181,23 @@ namespace {
 		return lexical_cast<T>(it->second);
 	}
 
+	template <typename T>
+	optional<T> get_opt_attr(attributes const &attr, string const &key) {
+		typedef optional<T> rtype;
+		attributes::const_iterator it = attr.find(key);
+		if (it == attr.end())
+			return rtype();
+
+		return rtype(lexical_cast<T>(it->second));
+	}
+
 	void parse_superblock(emitter *e, attributes const &attr) {
 		e->begin_superblock(get_attr<string>(attr, "uuid"),
 				    get_attr<uint64_t>(attr, "time"),
 				    get_attr<uint64_t>(attr, "transaction"),
 				    get_attr<uint32_t>(attr, "data_block_size"),
-				    get_attr<uint64_t>(attr, "nr_data_blocks"));
+				    get_attr<uint64_t>(attr, "nr_data_blocks"),
+				    get_opt_attr<uint64_t>(attr, "metadata_snap"));
 	}
 
 	void parse_device(emitter *e, attributes const &attr) {