AU: More graph utilities
EdgeProperties: support for listing blocks in a write-before
dependency. Blocks historically have only been listed for a
read-before dep. operator== for Extent and EdgeProperties.
Vertex: ability to mark invalid. An invalid vertex is not part of the
graph.
graph utils: Functions to add and drop dependencies.
Overloaded GetElement() to pull an element at a given index from
either a vector<Extent> or RepeatedPtrField<Extent>.
DumpGraph function, useful for debugging.
BUG=none
TEST=unittests
Review URL: http://codereview.chromium.org/3596007
diff --git a/graph_utils.h b/graph_utils.h
index fd602ea..6f7b9a2 100644
--- a/graph_utils.h
+++ b/graph_utils.h
@@ -19,11 +19,43 @@
// Returns the number of blocks represented by all extents in the edge.
uint64_t EdgeWeight(const Graph& graph, const Edge& edge);
+// These add a read-before dependency from graph[src] -> graph[dst]. If the dep
+// already exists, the block/s is/are added to the existing edge.
+void AddReadBeforeDep(Vertex* src,
+ Vertex::Index dst,
+ uint64_t block);
+void AddReadBeforeDepExtents(Vertex* src,
+ Vertex::Index dst,
+ const std::vector<Extent>& extents);
+
+void DropWriteBeforeDeps(Vertex::EdgeMap* edge_map);
+
+// For each node N in graph, drop all edges N->|index|.
+void DropIncomingEdgesTo(Graph* graph, Vertex::Index index);
+
// block must either be the next block in the last extent or a block
// in the next extent. This function will not handle inserting block
// into an arbitrary place in the extents.
void AppendBlockToExtents(std::vector<Extent>* extents, uint64_t block);
+// Get/SetElement are intentionally overloaded so that templated functions
+// can accept either type of collection of Extents.
+Extent GetElement(const std::vector<Extent>& collection, size_t index);
+Extent GetElement(
+ const google::protobuf::RepeatedPtrField<Extent>& collection,
+ size_t index);
+
+template<typename T>
+uint64_t BlocksInExtents(const T& collection) {
+ uint64_t ret = 0;
+ for (size_t i = 0; i < static_cast<size_t>(collection.size()); ++i) {
+ ret += GetElement(collection, i).num_blocks();
+ }
+ return ret;
+}
+
+void DumpGraph(const Graph& graph);
+
} // namespace graph_utils
} // namespace chromeos_update_engine