1 files changed, 236 insertions, 0 deletions
diff --git a/builtin/diff-tree.c b/builtin/diff-tree.c
new file mode 100644
index 0000000..86be634
--- /dev/null
+++ b/builtin/diff-tree.c
@@ -0,0 +1,236 @@
+#define USE_THE_INDEX_VARIABLE
+#include "builtin.h"
+#include "config.h"
+#include "diff.h"
+#include "commit.h"
+#include "gettext.h"
+#include "hex.h"
+#include "log-tree.h"
+#include "submodule.h"
+#include "read-cache-ll.h"
+#include "repository.h"
+#include "revision.h"
+#include "tree.h"
+
+static struct rev_info log_tree_opt;
+
+static int diff_tree_commit_oid(const struct object_id *oid)
+{
+	struct commit *commit = lookup_commit_reference(the_repository, oid);
+	if (!commit)
+		return -1;
+	return log_tree_commit(&log_tree_opt, commit);
+}
+
+/* Diff one or more commits. */
+static int stdin_diff_commit(struct commit *commit, const char *p)
+{
+	struct object_id oid;
+	struct commit_list **pptr = NULL;
+
+	/* Graft the fake parents locally to the commit */
+	while (isspace(*p++) && !parse_oid_hex(p, &oid, &p)) {
+		struct commit *parent = lookup_commit(the_repository, &oid);
+		if (!pptr) {
+			/* Free the real parent list */
+			free_commit_list(commit->parents);
+			commit->parents = NULL;
+			pptr = &(commit->parents);
+		}
+		if (parent) {
+			pptr = &commit_list_insert(parent, pptr)->next;
+		}
+	}
+	return log_tree_commit(&log_tree_opt, commit);
+}
+
+/* Diff two trees. */
+static int stdin_diff_trees(struct tree *tree1, const char *p)
+{
+	struct object_id oid;
+	struct tree *tree2;
+	if (!isspace(*p++) || parse_oid_hex(p, &oid, &p) || *p)
+		return error("Need exactly two trees, separated by a space");
+	tree2 = lookup_tree(the_repository, &oid);
+	if (!tree2 || parse_tree(tree2))
+		return -1;
+	printf("%s %s\n", oid_to_hex(&tree1->object.oid),
+			  oid_to_hex(&tree2->object.oid));
+	diff_tree_oid(&tree1->object.oid, &tree2->object.oid,
+		      "", &log_tree_opt.diffopt);
+	log_tree_diff_flush(&log_tree_opt);
+	return 0;
+}
+
+static int diff_tree_stdin(char *line)
+{
+	int len = strlen(line);
+	struct object_id oid;
+	struct object *obj;
+	const char *p;
+
+	if (!len || line[len-1] != '\n')
+		return -1;
+	line[len-1] = 0;
+	if (parse_oid_hex(line, &oid, &p))
+		return -1;
+	obj = parse_object(the_repository, &oid);
+	if (!obj)
+		return -1;
+	if (obj->type == OBJ_COMMIT)
+		return stdin_diff_commit((struct commit *)obj, p);
+	if (obj->type == OBJ_TREE)
+		return stdin_diff_trees((struct tree *)obj, p);
+	error("Object %s is a %s, not a commit or tree",
+	      oid_to_hex(&oid), type_name(obj->type));
+	return -1;
+}
+
+static const char diff_tree_usage[] =
+"git diff-tree [--stdin] [-m] [-s] [-v] [--no-commit-id] [--pretty]\n"
+"              [-t] [-r] [-c | --cc] [--combined-all-paths] [--root] [--merge-base]\n"
+"              [<common-diff-options>] <tree-ish> [<tree-ish>] [<path>...]\n"
+"\n"
+"  -r            diff recursively\n"
+"  -c            show combined diff for merge commits\n"
+"  --cc          show combined diff for merge commits removing uninteresting hunks\n"
+"  --combined-all-paths\n"
+"                show name of file in all parents for combined diffs\n"
+"  --root        include the initial commit as diff against /dev/null\n"
+COMMON_DIFF_OPTIONS_HELP;
+
+static void diff_tree_tweak_rev(struct rev_info *rev)
+{
+	if (!rev->diffopt.output_format) {
+		if (rev->dense_combined_merges)
+			rev->diffopt.output_format = DIFF_FORMAT_PATCH;
+		else
+			rev->diffopt.output_format = DIFF_FORMAT_RAW;
+	}
+}
+
+int cmd_diff_tree(int argc, const char **argv, const char *prefix)
+{
+	char line[1000];
+	struct object *tree1, *tree2;
+	static struct rev_info *opt = &log_tree_opt;
+	struct setup_revision_opt s_r_opt;
+	struct userformat_want w;
+	int read_stdin = 0;
+	int merge_base = 0;
+
+	if (argc == 2 && !strcmp(argv[1], "-h"))
+		usage(diff_tree_usage);
+
+	git_config(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, opt, prefix);
+	if (repo_read_index(the_repository) < 0)
+		die(_("index file corrupt"));
+	opt->abbrev = 0;
+	opt->diff = 1;
+	opt->disable_stdin = 1;
+	memset(&s_r_opt, 0, sizeof(s_r_opt));
+	s_r_opt.tweak = diff_tree_tweak_rev;
+
+	prefix = precompose_argv_prefix(argc, argv, prefix);
+	argc = setup_revisions(argc, argv, opt, &s_r_opt);
+
+	memset(&w, 0, sizeof(w));
+	userformat_find_requirements(NULL, &w);
+
+	if (!opt->show_notes_given && w.notes)
+		opt->show_notes = 1;
+	if (opt->show_notes)
+		load_display_notes(&opt->notes_opt);
+
+	while (--argc > 0) {
+		const char *arg = *++argv;
+
+		if (!strcmp(arg, "--stdin")) {
+			read_stdin = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--merge-base")) {
+			merge_base = 1;
+			continue;
+		}
+		usage(diff_tree_usage);
+	}
+
+	if (read_stdin && merge_base)
+		die(_("options '%s' and '%s' cannot be used together"), "--stdin", "--merge-base");
+	if (merge_base && opt->pending.nr != 2)
+		die(_("--merge-base only works with two commits"));
+
+	opt->diffopt.rotate_to_strict = 1;
+
+	/*
+	 * NOTE!  We expect "a..b" to expand to "^a b" but it is
+	 * perfectly valid for revision range parser to yield "b ^a",
+	 * which means the same thing. If we get the latter, i.e. the
+	 * second one is marked UNINTERESTING, we recover the original
+	 * order the user gave, i.e. "a..b", by swapping the trees.
+	 */
+	switch (opt->pending.nr) {
+	case 0:
+		if (!read_stdin)
+			usage(diff_tree_usage);
+		break;
+	case 1:
+		tree1 = opt->pending.objects[0].item;
+		diff_tree_commit_oid(&tree1->oid);
+		break;
+	case 2:
+		tree1 = opt->pending.objects[0].item;
+		tree2 = opt->pending.objects[1].item;
+		if (merge_base) {
+			struct object_id oid;
+
+			diff_get_merge_base(opt, &oid);
+			tree1 = lookup_object(the_repository, &oid);
+		} else if (tree2->flags & UNINTERESTING) {
+			SWAP(tree2, tree1);
+		}
+		diff_tree_oid(&tree1->oid, &tree2->oid, "", &opt->diffopt);
+		log_tree_diff_flush(opt);
+		break;
+	}
+
+	if (read_stdin) {
+		int saved_nrl = 0;
+		int saved_dcctc = 0;
+
+		opt->diffopt.rotate_to_strict = 0;
+		opt->diffopt.no_free = 1;
+		if (opt->diffopt.detect_rename) {
+			if (!the_index.cache)
+				repo_read_index(the_repository);
+			opt->diffopt.setup |= DIFF_SETUP_USE_SIZE_CACHE;
+		}
+		while (fgets(line, sizeof(line), stdin)) {
+			struct object_id oid;
+
+			if (get_oid_hex(line, &oid)) {
+				fputs(line, stdout);
+				fflush(stdout);
+			}
+			else {
+				diff_tree_stdin(line);
+				if (saved_nrl < opt->diffopt.needed_rename_limit)
+					saved_nrl = opt->diffopt.needed_rename_limit;
+				if (opt->diffopt.degraded_cc_to_c)
+					saved_dcctc = 1;
+			}
+		}
+		opt->diffopt.degraded_cc_to_c = saved_dcctc;
+		opt->diffopt.needed_rename_limit = saved_nrl;
+		opt->diffopt.no_free = 0;
+		diff_free(&opt->diffopt);
+	}
+
+	return diff_result_code(&opt->diffopt);
+}