[cache_restore/dump] hint_width work.

dump/restore cycle works again.

Gemfile.lock

@@ -21,9 +21,9 @@ GEM
       multi_json (~> 1.3)
     multi_json (1.8.0)
     multi_test (0.0.2)
-    rspec-expectations (2.14.2)
+    rspec-expectations (2.14.3)
       diff-lcs (>= 1.1.3, < 2.0)
-    thinp_xml (0.0.10)
+    thinp_xml (0.0.12)
       ejt_command_line (= 0.0.2)
 
 PLATFORMS

caching/cache_dump.cc

@@ -36,7 +36,9 @@ namespace {
 		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));
+		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();
 

caching/emitter.h

@@ -20,7 +20,8 @@ namespace caching {
 		virtual void begin_superblock(std::string const &uuid,
 					      pd::block_address block_size,
 					      pd::block_address nr_cache_blocks,
-					      std::string const &policy) = 0;
+					      std::string const &policy,
+					      size_t hint_width) = 0;
 
 		virtual void end_superblock() = 0;
 

caching/hint_array.cc

@@ -36,6 +36,8 @@ namespace {
 
 			all_widths
 #undef xx
+		default:
+			throw runtime_error("invalid hint width");
 		}
 
 		// never get here
@@ -59,6 +61,8 @@ namespace {
 #define xx(n)	case n:	return mk_array<n>(tm, root, nr_entries)
 			all_widths
 #undef xx
+		default:
+			throw runtime_error("invalid hint width");
 		}
 
 		// never get here

caching/hint_array.h

@@ -19,12 +19,12 @@ namespace caching {
 			// FIXME: slow copying for now
 			static void unpack(disk_type const &disk, value_type &value) {
 				for (unsigned byte = 0; byte < WIDTH; byte++)
-					value[byte] = disk[byte];
+					value.at(byte) = disk[byte];
 			}
 
 			static void pack(value_type const &value, disk_type &disk) {
 				for (unsigned byte = 0; byte < WIDTH; byte++)
-					disk[byte] = value[byte];
+					disk[byte] = value.at(byte);
 			}
 		};
 

caching/metadata.cc

@@ -57,6 +57,14 @@ metadata::commit()
 	commit_superblock();
 }
 
+void
+metadata::setup_hint_array(size_t width)
+{
+	if (width > 0)
+		hints_ = hint_array::ptr(
+			new hint_array(tm_, width));
+}
+
 void
 metadata::init_superblock()
 {
@@ -85,7 +93,9 @@ metadata::create_metadata(block_manager<>::ptr bm)
 	tm_->set_sm(metadata_sm_);
 
 	mappings_ = mapping_array::ptr(new mapping_array(tm_, mapping_array::ref_counter()));
-//      hints_ = hint_array::ptr(new hint_array(tm_));
+
+	// We can't instantiate the hint array yet, since we don't know the
+	// hint width.
 }
 
 void

caching/metadata.h

@@ -28,6 +28,8 @@ namespace caching {
 		metadata(block_manager<>::ptr bm, open_type ot);
 
 		void commit();
+		void setup_hint_array(size_t width);
+
 
 		typedef persistent_data::transaction_manager tm;
 		tm::ptr tm_;

caching/restore_emitter.cc

@@ -23,7 +23,8 @@ namespace {
 		virtual void begin_superblock(std::string const &uuid,
 					      pd::block_address block_size,
 					      pd::block_address nr_cache_blocks,
-					      std::string const &policy) {
+					      std::string const &policy,
+					      size_t hint_width) {
 
 			superblock &sb = md_->sb_;
 
@@ -31,11 +32,13 @@ namespace {
 			memset(sb.uuid, 0, sizeof(sb.uuid));
 			sb.magic = caching::superblock_detail::SUPERBLOCK_MAGIC;
 			sb.version = 0; // FIXME: fix
-			// strncpy(sb.policy_name, policy.c_str(), sizeof(sb.policy_name));
+			strncpy((char *) sb.policy_name, policy.c_str(), sizeof(sb.policy_name));
 			memset(sb.policy_version, 0, sizeof(sb.policy_version));
-			sb.policy_hint_size = 0; // FIXME: fix
+			sb.policy_hint_size = hint_width;
+			md_->setup_hint_array(hint_width);
 
-			memset(sb.metadata_space_map_root, 0, sizeof(sb.metadata_space_map_root));
+			memset(sb.metadata_space_map_root, 0,
+			       sizeof(sb.metadata_space_map_root));
 			sb.mapping_root = 0;
 			sb.hint_root = 0;
 
@@ -60,6 +63,9 @@ namespace {
 			unmapped_value.oblock_ = 0;
 			unmapped_value.flags_ = 0;
 			md_->mappings_->grow(nr_cache_blocks, unmapped_value);
+
+			vector<unsigned char> hint_value(hint_width, '\0');
+			md_->hints_->grow(nr_cache_blocks, hint_value);
 		}
 
 		virtual void end_superblock() {

caching/superblock.cc

@@ -22,6 +22,7 @@ superblock_traits::unpack(superblock_disk const &disk, superblock &core)
 		core.policy_version[i] = to_cpu<uint32_t>(disk.policy_version[i]);
 
 	core.policy_hint_size = to_cpu<uint32_t>(disk.policy_hint_size);
+	cerr << "unpacking: hint width = " << core.policy_hint_size << endl;
 
 	::memcpy(core.metadata_space_map_root,
 		 disk.metadata_space_map_root,

caching/xml_format.cc

@@ -33,12 +33,14 @@ namespace {
 		void begin_superblock(std::string const &uuid,
 				      block_address block_size,
 				      block_address nr_cache_blocks,
-				      std::string const &policy) {
+				      std::string const &policy,
+				      size_t hint_width) {
 			indent();
 			out_ << "<superblock uuid=\"" << uuid << "\""
 			     << " block_size=\"" << block_size << "\""
 			     << " nr_cache_blocks=\"" << nr_cache_blocks << "\""
-			     << " policy=\"" << policy << "\">" << endl;
+			     << " policy=\"" << policy << "\""
+			     << " hint_width=\"" << hint_width << "\">" << endl;
 			inc();
 		}
 
@@ -164,7 +166,8 @@ namespace {
 		e->begin_superblock(get_attr<string>(attr, "uuid"),
 				    get_attr<uint64_t>(attr, "block_size"),
 				    get_attr<uint64_t>(attr, "nr_cache_blocks"),
-				    get_attr<string>(attr, "policy"));
+				    get_attr<string>(attr, "policy"),
+				    get_attr<size_t>(attr, "hint_width"));
 	}
 
 	bool to_bool(string const &str) {