[caching] factor metadata_dump out of cache_dump

Makefile.in

@@ -40,6 +40,7 @@ SOURCE=\
 	caching/superblock.cc \
 	caching/mapping_array.cc \
 	caching/metadata.cc \
+	caching/metadata_dump.cc \
 	caching/restore_emitter.cc \
 	caching/xml_format.cc \
 	\
@@ -243,6 +244,7 @@ CACHE_CHECK_SOURCE=\
 	caching/superblock.cc \
 	caching/mapping_array.cc \
 	caching/metadata.cc \
+	caching/metadata_dump.cc \
 	caching/restore_emitter.cc \
 	caching/xml_format.cc
 

caching/cache_dump.cc

@@ -6,6 +6,7 @@
 #include "version.h"
 #include "caching/mapping_array.h"
 #include "caching/metadata.h"
+#include "caching/metadata_dump.h"
 #include "caching/xml_format.h"
 #include "persistent-data/file_utils.h"
 
@@ -23,75 +24,6 @@ namespace {
 		bool repair_;
 	};
 
-	string to_string(unsigned char const *data) {
-		// FIXME: we're assuming the data is zero terminated here
-		return std::string(reinterpret_cast<char const *>(data));
-	}
-
-	void raise_metadata_damage() {
-		throw std::runtime_error("metadata contains errors (run cache_check for details).\n"
-					 "perhaps you wanted to run with --repair");
-	}
-
-	//--------------------------------
-
-	class mapping_emitter : public mapping_visitor {
-	public:
-		mapping_emitter(emitter::ptr e)
-			: e_(e) {
-		}
-
-		void visit(block_address cblock, mapping const &m) {
-			if (m.flags_ & M_VALID)
-				e_->mapping(cblock, m.oblock_, m.flags_ & M_DIRTY);
-		}
-
-	private:
-		emitter::ptr e_;
-	};
-
-	struct ignore_mapping_damage : public mapping_array_damage::damage_visitor {
-		virtual void visit(mapping_array_damage::missing_mappings const &d) {}
-		virtual void visit(mapping_array_damage::invalid_mapping const &d) {}
-	};
-
-	class fatal_mapping_damage : public mapping_array_damage::damage_visitor {
-	public:
-		virtual void visit(mapping_array_damage::missing_mappings const &d) {
-			raise_metadata_damage();
-		}
-
-		virtual void visit(mapping_array_damage::invalid_mapping const &d) {
-			raise_metadata_damage();
-		}
-	};
-
-	//--------------------------------
-
-	class hint_emitter : public hint_visitor {
-	public:
-		hint_emitter(emitter::ptr e)
-			: e_(e) {
-		}
-
-		virtual void visit(block_address cblock, std::vector<unsigned char> const &data) {
-			e_->hint(cblock, data);
-		}
-
-	private:
-		emitter::ptr e_;
-	};
-
-	struct ignore_hint_damage : public hint_array_damage::damage_visitor {
-		virtual void visit(hint_array_damage::missing_hints const &d) {}
-	};
-
-	class fatal_hint_damage : public hint_array_damage::damage_visitor {
-		virtual void visit(hint_array_damage::missing_hints const &d) {
-			raise_metadata_damage();
-		}
-	};
-
 	//--------------------------------
 
 	string const STDOUT_PATH("-");
@@ -100,65 +32,26 @@ namespace {
 		return output == STDOUT_PATH;
 	}
 
-	int dump_(string const &dev, ostream &out, flags const &fs) {
-		block_manager<>::ptr bm = open_bm(dev, block_io<>::READ_ONLY);
-		metadata::ptr md(new metadata(bm, metadata::OPEN));
-		emitter::ptr e = create_xml_emitter(out);
-
-		superblock const &sb = md->sb_;
-		e->begin_superblock(to_string(sb.uuid), sb.data_block_size,
-				    sb.cache_blocks, to_string(sb.policy_name),
-				    sb.policy_hint_size);
-
-		e->begin_mappings();
-		{
-			namespace mad = mapping_array_damage;
-
-			mapping_emitter me(e);
-			ignore_mapping_damage ignore;
-			fatal_mapping_damage fatal;
-			mad::damage_visitor &dv = fs.repair_ ?
-				static_cast<mad::damage_visitor &>(ignore) :
-				static_cast<mad::damage_visitor &>(fatal);
-			walk_mapping_array(*md->mappings_, me, dv);
-		}
-		e->end_mappings();
-
-		// walk hints
-		e->begin_hints();
-		{
-			using namespace hint_array_damage;
-
-			hint_emitter he(e);
-			ignore_hint_damage ignore;
-			fatal_hint_damage fatal;
-			damage_visitor &dv = fs.repair_ ?
-				static_cast<damage_visitor &>(ignore) :
-				static_cast<damage_visitor &>(fatal);
-			md->hints_->walk(he, dv);
-		}
-		e->end_hints();
-
-		// FIXME: walk discards
-
-		e->end_superblock();
-
-		return 0;
-	}
-
 	int dump(string const &dev, string const &output, flags const &fs) {
 		try {
-			if (want_stdout(output))
+			block_manager<>::ptr bm = open_bm(dev, block_io<>::READ_ONLY);
-				return dump_(dev, cout, fs);
+			metadata::ptr md(new metadata(bm, metadata::OPEN));
-			else {
+
+			if (want_stdout(output)) {
+				emitter::ptr e = create_xml_emitter(cout);
+				metadata_dump(md, e, fs.repair_);
+			} else {
 				ofstream out(output.c_str());
-				return dump_(dev, out, fs);
+				emitter::ptr e = create_xml_emitter(out);
+				metadata_dump(md, e, fs.repair_);
 			}
 
 		} catch (std::exception &e) {
 			cerr << e.what() << endl;
 			return 1;
 		}
+
+		return 0;
 	}
 
 	void usage(ostream &out, string const &cmd) {

caching/metadata_dump.cc

@@ -0,0 +1,124 @@
+#include "caching/metadata_dump.h"
+
+using namespace std;
+using namespace caching;
+
+//----------------------------------------------------------------
+
+namespace {
+	string to_string(unsigned char const *data) {
+		// FIXME: we're assuming the data is zero terminated here
+		return std::string(reinterpret_cast<char const *>(data));
+	}
+
+	void raise_metadata_damage() {
+		throw std::runtime_error("metadata contains errors (run cache_check for details).\n"
+					 "perhaps you wanted to run with --repair");
+	}
+
+	//--------------------------------
+
+	class mapping_emitter : public mapping_visitor {
+	public:
+		mapping_emitter(emitter::ptr e)
+			: e_(e) {
+		}
+
+		void visit(block_address cblock, mapping const &m) {
+			if (m.flags_ & M_VALID)
+				e_->mapping(cblock, m.oblock_, m.flags_ & M_DIRTY);
+		}
+
+	private:
+		emitter::ptr e_;
+	};
+
+	struct ignore_mapping_damage : public mapping_array_damage::damage_visitor {
+		virtual void visit(mapping_array_damage::missing_mappings const &d) {}
+		virtual void visit(mapping_array_damage::invalid_mapping const &d) {}
+	};
+
+	class fatal_mapping_damage : public mapping_array_damage::damage_visitor {
+	public:
+		virtual void visit(mapping_array_damage::missing_mappings const &d) {
+			raise_metadata_damage();
+		}
+
+		virtual void visit(mapping_array_damage::invalid_mapping const &d) {
+			raise_metadata_damage();
+		}
+	};
+
+	//--------------------------------
+
+	class hint_emitter : public hint_visitor {
+	public:
+		hint_emitter(emitter::ptr e)
+			: e_(e) {
+		}
+
+		virtual void visit(block_address cblock, std::vector<unsigned char> const &data) {
+			e_->hint(cblock, data);
+		}
+
+	private:
+		emitter::ptr e_;
+	};
+
+	struct ignore_hint_damage : public hint_array_damage::damage_visitor {
+		virtual void visit(hint_array_damage::missing_hints const &d) {}
+	};
+
+	class fatal_hint_damage : public hint_array_damage::damage_visitor {
+		virtual void visit(hint_array_damage::missing_hints const &d) {
+			raise_metadata_damage();
+		}
+	};
+}
+
+//----------------------------------------------------------------
+
+void
+caching::metadata_dump(metadata::ptr md, emitter::ptr e, bool repair)
+{
+	superblock const &sb = md->sb_;
+	e->begin_superblock(to_string(sb.uuid), sb.data_block_size,
+			    sb.cache_blocks, to_string(sb.policy_name),
+			    sb.policy_hint_size);
+
+	e->begin_mappings();
+	{
+		namespace mad = mapping_array_damage;
+
+		mapping_emitter me(e);
+		ignore_mapping_damage ignore;
+		fatal_mapping_damage fatal;
+		mad::damage_visitor &dv = repair ?
+			static_cast<mad::damage_visitor &>(ignore) :
+			static_cast<mad::damage_visitor &>(fatal);
+		walk_mapping_array(*md->mappings_, me, dv);
+	}
+	e->end_mappings();
+
+	// walk hints
+	e->begin_hints();
+	{
+		using namespace hint_array_damage;
+
+		hint_emitter he(e);
+		ignore_hint_damage ignore;
+		fatal_hint_damage fatal;
+		damage_visitor &dv = repair ?
+			static_cast<damage_visitor &>(ignore) :
+			static_cast<damage_visitor &>(fatal);
+		md->hints_->walk(he, dv);
+	}
+	e->end_hints();
+
+	// FIXME: walk discards
+
+	e->end_superblock();
+}
+
+//----------------------------------------------------------------
+

caching/metadata_dump.h

@@ -0,0 +1,17 @@
+#ifndef CACHING_METADATA_DUMP_H
+#define CACHING_METADATA_DUMP_H
+
+#include "caching/metadata.h"
+#include "caching/emitter.h"
+
+//----------------------------------------------------------------
+
+namespace caching {
+	// If 'repair' is set then any metadata damage will be stepped
+	// around.  Otherwise an exception will be thrown.
+	void metadata_dump(metadata::ptr md, emitter::ptr out, bool repair);
+}
+
+//----------------------------------------------------------------
+
+#endif