[PATCH v3 3/3] cat-file: add "--literally" option

@@ -9,7 +9,8 @@
 #include "userdiff.h"
 #include "streaming.h"
 
-static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
+static int cat_one_file(int opt, const char *exp_type, const char *obj_name,
+			int literally)
 {
 	unsigned char sha1[20];
 	enum object_type type;

@@ -23,6 +24,14 @@ static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
 	buf = NULL;
 	switch (opt) {
 	case 't':
+		if (literally) {
+			buf = sha1_object_info_literally(sha1);
+			if (!buf)
+				die("git cat-file --literally -t %s: failed",
+					obj_name);
+			printf("%s\n", buf);
+			return 0;
+		}
 		type = sha1_object_info(sha1, NULL);
 		if (type > 0) {
 			printf("%s\n", typename(type));

@@ -323,7 +332,7 @@ static int batch_objects(struct batch_options *opt)
 }
 
 static const char * const cat_file_usage[] = {
-	N_("git cat-file (-t | -s | -e | -p | <type> | --textconv) <object>"),
+	N_("git cat-file (-t|-s|-e|-p|<type>|--textconv|-t --literally) <object>"),
 	N_("git cat-file (--batch | --batch-check) < <list-of-objects>"),
 	NULL
 };

@@ -359,6 +368,7 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
 	int opt = 0;
 	const char *exp_type = NULL, *obj_name = NULL;
 	struct batch_options batch = {0};
+	int literally = 0;
 
 	const struct option options[] = {
 		OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),

@@ -369,6 +379,8 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
 		OPT_SET_INT('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
 		OPT_SET_INT(0, "textconv", &opt,
 			    N_("for blob objects, run textconv on object's content"), 'c'),
+		OPT_BOOL( 0, "literally", &literally,
+			  N_("show the type of the given loose object, use for debugging")),
 		{ OPTION_CALLBACK, 0, "batch", &batch, "format",
 			N_("show info and content of objects fed from the standard input"),
 			PARSE_OPT_OPTARG, batch_option_callback },

@@ -380,7 +392,7 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
 
 	git_config(git_cat_file_config, NULL);
 
-	if (argc != 3 && argc != 2)
+	if (argc != 3 && argc != 2 && argc != 4)
 		usage_with_options(cat_file_usage, options);
 
 	argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);

@@ -405,5 +417,10 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
 	if (batch.enabled)
 		return batch_objects(&batch);
 
-	return cat_one_file(opt, exp_type, obj_name);
+	if (literally && opt == 't')
+		return cat_one_file(opt, exp_type, obj_name, literally);
+	else if (literally)
+		usage_with_options(cat_file_usage, options);
+
+	return cat_one_file(opt, exp_type, obj_name, literally);
 }