3 files changed, 24 insertions, 5 deletions
diff --git a/include/git2/sys/diff.h b/include/git2/sys/diff.h
index 48d72f4f9..034d5c478 100644
--- a/include/git2/sys/diff.h
+++ b/include/git2/sys/diff.h
@@ -61,10 +61,13 @@ GIT_EXTERN(int) git_diff_print_callback__to_file_handle(
 	void *payload); /*< payload must be a `FILE *` */
 
 
+/**
+ * Performance data from diffing
+ */
 typedef struct {
 	unsigned int version;
-	size_t stat_calls;
-	size_t oid_calculations;
+	size_t stat_calls; /*< Number of stat() calls performed */
+	size_t oid_calculations; /*< Number of ID calculations */
 } git_diff_perfdata;
 
 #define GIT_DIFF_PERFDATA_VERSION 1
diff --git a/include/git2/sys/hashsig.h b/include/git2/sys/hashsig.h
index cd735e1b5..2bc32f394 100644
--- a/include/git2/sys/hashsig.h
+++ b/include/git2/sys/hashsig.h
@@ -16,6 +16,9 @@ GIT_BEGIN_DECL
  */
 typedef struct git_hashsig git_hashsig;
 
+/**
+ * Options for hashsig calculation
+ */
 typedef enum {
 	GIT_HASHSIG_NORMAL = 0, /* use all data */
 	GIT_HASHSIG_IGNORE_WHITESPACE = 1, /* ignore whitespace */
diff --git a/include/git2/sys/transport.h b/include/git2/sys/transport.h
index b50438ecd..69d4e15c5 100644
--- a/include/git2/sys/transport.h
+++ b/include/git2/sys/transport.h
@@ -21,6 +21,11 @@
 
 GIT_BEGIN_DECL
 
+/**
+ * Flags to pass to transport
+ *
+ * Currently unused.
+ */
 typedef enum {
 	GIT_TRANSPORTFLAGS_NONE = 0,
 } git_transport_flags_t;
@@ -286,12 +291,20 @@ typedef int (*git_smart_subtransport_cb)(
 	git_smart_subtransport **out,
 	git_transport* owner);
 
+/**
+ * Definition for a "subtransport"
+ *
+ * This is used to let the smart protocol code know about the protocol
+ * which you are implementing.
+ */
 typedef struct git_smart_subtransport_definition {
-	/* The function to use to create the git_smart_subtransport */
+	/** The function to use to create the git_smart_subtransport */
 	git_smart_subtransport_cb callback;
 
-	/* True if the protocol is stateless; false otherwise. For example,
-	 * http:// is stateless, but git:// is not. */
+	/**
+	 * True if the protocol is stateless; false otherwise. For example,
+	 * http:// is stateless, but git:// is not.
+	 */
 	unsigned rpc;
 } git_smart_subtransport_definition;