2 files changed, 62 insertions, 8 deletions

diff --git a/include/git2/index.h b/include/git2/index.h
index 3d4bd15a8..fcfe4be3d 100644
--- a/include/git2/index.h
+++ b/include/git2/index.h
@@ -551,9 +551,9 @@ GIT_EXTERN(const git_index_reuc_entry *) git_index_reuc_get_byindex(git_index *i
  * @return 0 or an error code
  */
 GIT_EXTERN(int) git_index_reuc_add(git_index *index, const char *path,
-	int ancestor_mode, git_oid *ancestor_id,
-	int our_mode, git_oid *our_id,
-	int their_mode, git_oid *their_id);
+	int ancestor_mode, const git_oid *ancestor_id,
+	int our_mode, const git_oid *our_id,
+	int their_mode, const git_oid *their_id);
 
 /**
  * Remove an resolve undo entry from the index
diff --git a/include/git2/merge.h b/include/git2/merge.h
index f4c5d9881..43a61f0e4 100644
--- a/include/git2/merge.h
+++ b/include/git2/merge.h
@@ -7,20 +7,52 @@
 #ifndef INCLUDE_git_merge_h__
 #define INCLUDE_git_merge_h__
 
-#include "common.h"
-#include "types.h"
-#include "oid.h"
+#include "git2/common.h"
+#include "git2/types.h"
+#include "git2/oid.h"
+#include "git2/checkout.h"
+#include "git2/index.h"
 
 /**
  * @file git2/merge.h
- * @brief Git merge-base routines
- * @defgroup git_revwalk Git merge-base routines
+ * @brief Git merge routines
+ * @defgroup git_merge Git merge routines
  * @ingroup Git
  * @{
  */
 GIT_BEGIN_DECL
 
 /**
+ * Flags for tree_many diff options.  A combination of these flags can be
+ * passed in via the `flags` value in the `git_diff_tree_many_options`.
+ */
+typedef enum {
+} git_merge_tree_flags;
+
+/**
+ * Automerge options for `git_merge_trees_opts`.
+ */ 
+typedef enum {
+	GIT_MERGE_AUTOMERGE_NORMAL = 0,
+	GIT_MERGE_AUTOMERGE_NONE = 1,
+	GIT_MERGE_AUTOMERGE_FAVOR_OURS = 2,
+	GIT_MERGE_AUTOMERGE_FAVOR_THEIRS = 3,
+} git_merge_automerge_flags;
+
+
+typedef struct {
+	unsigned int version;
+	git_merge_tree_flags flags;
+	
+	/** Flags for automerging content. */
+	git_merge_automerge_flags automerge_flags;
+} git_merge_tree_opts;
+
+#define GIT_MERGE_TREE_OPTS_VERSION 1
+#define GIT_MERGE_TREE_OPTS_INIT {GIT_MERGE_TREE_OPTS_VERSION}
+
+
+/**
  * Find a merge base between two commits
  *
  * @param out the OID of a merge base between 'one' and 'two'
@@ -50,6 +82,28 @@ GIT_EXTERN(int) git_merge_base_many(
 	const git_oid input_array[],
 	size_t length);
 
+/**
+ * Merge two trees, producing a `git_index` that reflects the result of
+ * the merge.
+ *
+ * The returned index must be freed explicitly with `git_index_free`.
+ *
+ * @param out pointer to store the index result in
+ * @param repo repository that contains the given trees
+ * @param ancestor_tree the common ancestor between the trees (or null if none)
+ * @param our_tree the tree that reflects the destination tree
+ * @param their_tree the tree to merge in to `our_tree`
+ * @param opts the merge tree options (or null for defaults)
+ * @return zero on success, -1 on failure.
+ */
+GIT_EXTERN(int) git_merge_trees(
+	git_index **out,
+	git_repository *repo,
+	const git_tree *ancestor_tree,
+	const git_tree *our_tree,
+	const git_tree *their_tree,
+	const git_merge_tree_opts *opts);
+
 /** @} */
 GIT_END_DECL
 #endif