1 files changed, 93 insertions, 0 deletions
diff --git a/builtin/diff-files.c b/builtin/diff-files.c
new file mode 100644
index 0000000000..ea91347ce2
--- /dev/null
+++ b/builtin/diff-files.c
@@ -0,0 +1,93 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+
+#define USE_THE_REPOSITORY_VARIABLE
+#define DISABLE_SIGN_COMPARE_WARNINGS
+
+#include "builtin.h"
+#include "config.h"
+#include "diff.h"
+#include "diff-merges.h"
+#include "commit.h"
+#include "preload-index.h"
+#include "revision.h"
+
+static const char diff_files_usage[] =
+"git diff-files [-q] [-0 | -1 | -2 | -3 | -c | --cc] [<common-diff-options>] [<path>...]"
+"\n"
+COMMON_DIFF_OPTIONS_HELP;
+
+int cmd_diff_files(int argc,
+		   const char **argv,
+		   const char *prefix,
+		   struct repository *repo UNUSED)
+{
+	struct rev_info rev;
+	int result;
+	unsigned options = 0;
+
+	show_usage_if_asked(argc, argv, diff_files_usage);
+
+	repo_config(the_repository, git_diff_basic_config, NULL); /* no "diff" UI options */
+
+	prepare_repo_settings(the_repository);
+	the_repository->settings.command_requires_full_index = 0;
+
+	repo_init_revisions(the_repository, &rev, prefix);
+	rev.abbrev = 0;
+
+	/*
+	 * Consider "intent-to-add" files as new by default, unless
+	 * explicitly specified in the command line or anywhere else.
+	 */
+	rev.diffopt.ita_invisible_in_index = 1;
+
+	prefix = precompose_argv_prefix(argc, argv, prefix);
+
+	argc = setup_revisions(argc, argv, &rev, NULL);
+	while (1 < argc && argv[1][0] == '-') {
+		if (!strcmp(argv[1], "--base"))
+			rev.max_count = 1;
+		else if (!strcmp(argv[1], "--ours"))
+			rev.max_count = 2;
+		else if (!strcmp(argv[1], "--theirs"))
+			rev.max_count = 3;
+		else if (!strcmp(argv[1], "-q"))
+			options |= DIFF_SILENT_ON_REMOVED;
+		else
+			usage(diff_files_usage);
+		argv++; argc--;
+	}
+	if (!rev.diffopt.output_format)
+		rev.diffopt.output_format = DIFF_FORMAT_RAW;
+	rev.diffopt.rotate_to_strict = 1;
+
+	/*
+	 * Make sure there are NO revision (i.e. pending object) parameter,
+	 * rev.max_count is reasonable (0 <= n <= 3), and
+	 * there is no other revision filtering parameters.
+	 */
+	if (rev.pending.nr ||
+	    rev.min_age != -1 || rev.max_age != -1 ||
+	    3 < rev.max_count)
+		usage(diff_files_usage);
+
+	/*
+	 * "diff-files --base -p" should not combine merges because it
+	 * was not asked to.  "diff-files -c -p" should not densify
+	 * (the user should ask with "diff-files --cc" explicitly).
+	 */
+	if (rev.max_count == -1 &&
+	    (rev.diffopt.output_format & DIFF_FORMAT_PATCH))
+		diff_merges_set_dense_combined_if_unset(&rev);
+
+	if (repo_read_index_preload(the_repository, &rev.diffopt.pathspec, 0) < 0)
+		die_errno("repo_read_index_preload");
+	run_diff_files(&rev, options);
+	result = diff_result_code(&rev);
+	release_revisions(&rev);
+	return result;
+}