indexer: start writing the stream indexer

This will allow us to index a packfile as soon as we receive it from
the network as well as storing it with its final name so we don't need
to pass temporary file names around.

include/git2/indexer.h

@@ -13,16 +13,22 @@
 GIT_BEGIN_DECL
 
 /**
- * This is passed as the first argument to the callback to allow the
- * user to see the progress.
+ * Create a new streaming indexer instance
+ *
+ * @param out where to store the inexer instance
+ * @param path to the gitdir (metadata directory)
  */
-typedef struct git_indexer_stats {
-	unsigned int total;
-	unsigned int processed;
-} git_indexer_stats;
-
+GIT_EXTERN(int) git_indexer_stream_new(git_indexer_stream **out, const char *gitdir);
 
-typedef struct git_indexer git_indexer;
+/**
+ * Add data to the indexer
+ *
+ * @param idx the indexer
+ * @param data the data to add
+ * @param size the size of the data
+ * @param stats stat storage
+ */
+GIT_EXTERN(int) git_indexer_stream_add(git_indexer_stream *idx, const void *data, size_t size, git_indexer_stats *stats);
 
 /**
  * Create a new indexer instance

include/git2/types.h

@@ -171,6 +171,15 @@ typedef struct git_remote git_remote;
 
 typedef struct git_remote_head git_remote_head;
 
+/** Information about the progress of the indexer  */
+typedef struct git_indexer_stats {
+	unsigned int total;
+	unsigned int processed;
+} git_indexer_stats;
+
+typedef struct git_indexer git_indexer;
+typedef struct git_indexer_stream git_indexer_stream;
+
 /** @} */
 GIT_END_DECL