Add geef:oid_fmt(Oid)

c_src/geef.c

@@ -1,6 +1,7 @@
 #include "erl_nif.h"
 #include "repository.h"
 #include "reference.h"
+#include "oid.h"
 #include "geef.h"
 #include <stdio.h>
 #include <string.h>
@@ -78,6 +79,7 @@ static ErlNifFunc geef_funcs[] =
 	{"reference_lookup", 2, geef_reference_lookup},
 	{"reference_resolve", 1, geef_reference_resolve},
 	{"reference_id", 1, geef_reference_id},
+	{"oid_fmt", 1, geef_oid_fmt},
 };
 
 ERL_NIF_INIT(geef, geef_funcs, load, NULL, NULL, unload)

c_src/oid.c

@@ -0,0 +1,24 @@
+#include <git2.h>
+#include "geef.h"
+#include "oid.h"
+
+ERL_NIF_TERM
+geef_oid_fmt(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
+{
+	ErlNifBinary bin, bin_out;
+	git_oid id;
+
+	if (!enif_inspect_binary(env, argv[0], &bin))
+		return enif_make_badarg(env);
+
+	if (bin.size < GIT_OID_RAWSZ)
+		return enif_make_badarg(env);
+
+	if (!enif_alloc_binary(GIT_OID_HEXSZ, &bin_out))
+		return atoms.error;
+
+	git_oid_fromraw(&id, bin.data);
+	git_oid_fmt((char *)bin_out.data, &id);
+
+	return enif_make_binary(env, &bin_out);
+}

c_src/oid.h

@@ -0,0 +1,9 @@
+#ifndef GEEF_OID_H
+#define GEEF_OID_H
+
+#include "erl_nif.h"
+#include <git2.h>
+
+ERL_NIF_TERM geef_oid_fmt(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+#endif

src/geef.erl

@@ -2,7 +2,7 @@
 -export([hex_to_raw/1, repository/1, repository_get_path/1, repository_get_odb/1,
 	 repository_init/2, repository_is_bare/1, repository_get_workdir/1, reference_list/1,
 	 reference_to_id/2, reference_glob/2, reference_lookup/2, reference_resolve/1,
-	 reference_id/1, odb_object_exists/2]).
+	 reference_id/1, odb_object_exists/2, oid_fmt/1]).
 -on_load(load_enif/0).
 
 hex_to_raw(_Val) ->
@@ -55,6 +55,9 @@ repository(Path) ->
 odb_object_exists(_Val, _Val) ->
     nif_error(?LINE).
 
+oid_fmt(_Oid) ->
+    nif_error(?LINE).
+
 nif_error(Line) ->
     exit({nif_not_loaded,module,?MODULE,line,Line}).