Merge remote branch 'ko/master' into jc/read-tree-cache-tree-fix

* ko/master: (2325 commits)
  Git 1.7.2-rc2
  backmerge a few more fixes to 1.7.1.X series
  fix git branch -m in presence of cross devices
  t/t0006: specify timezone as EST5 not EST to comply with POSIX
  add missing && to submodule-merge testcase
  t/README: document more test helpers
  test-date: fix sscanf type conversion
  xdiff: optimise for no whitespace difference when ignoring whitespace.
  gitweb: Move evaluate_gitweb_config out of run_request
  parse_date: fix signedness in timezone calculation
  t0006: test timezone parsing
  rerere.txt: Document forget subcommand
  t/README: proposed rewording...
  t/README: Document the do's and don'ts of tests
  t/README: Add a section about skipping tests
  t/README: Document test_expect_code
  t/README: Document test_external*
  t/README: Document the prereq functions, and 3-arg test_*
  t/README: Typo: paralell -> parallel
  t/README: The trash is in 't/trash directory.$name'
  ...

Conflicts:
	builtin-read-tree.c

1 files changed, 180 insertions, 0 deletions

diff --git a/builtin/diff-tree.c b/builtin/diff-tree.c
new file mode 100644
index 0000000000..3c78bda566
--- /dev/null
+++ b/builtin/diff-tree.c
@@ -0,0 +1,180 @@
+#include "cache.h"
+#include "diff.h"
+#include "commit.h"
+#include "log-tree.h"
+#include "builtin.h"
+
+static struct rev_info log_tree_opt;
+
+static int diff_tree_commit_sha1(const unsigned char *sha1)
+{
+	struct commit *commit = lookup_commit_reference(sha1);
+	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, char *line, int len)
+{
+	unsigned char sha1[20];
+	if (isspace(line[40]) && !get_sha1_hex(line+41, sha1)) {
+		/* Graft the fake parents locally to the commit */
+		int pos = 41;
+		struct commit_list **pptr, *parents;
+
+		/* Free the real parent list */
+		for (parents = commit->parents; parents; ) {
+			struct commit_list *tmp = parents->next;
+			free(parents);
+			parents = tmp;
+		}
+		commit->parents = NULL;
+		pptr = &(commit->parents);
+		while (line[pos] && !get_sha1_hex(line + pos, sha1)) {
+			struct commit *parent = lookup_commit(sha1);
+			if (parent) {
+				pptr = &commit_list_insert(parent, pptr)->next;
+			}
+			pos += 41;
+		}
+	}
+	return log_tree_commit(&log_tree_opt, commit);
+}
+
+/* Diff two trees. */
+static int stdin_diff_trees(struct tree *tree1, char *line, int len)
+{
+	unsigned char sha1[20];
+	struct tree *tree2;
+	if (len != 82 || !isspace(line[40]) || get_sha1_hex(line + 41, sha1))
+		return error("Need exactly two trees, separated by a space");
+	tree2 = lookup_tree(sha1);
+	if (!tree2 || parse_tree(tree2))
+		return -1;
+	printf("%s %s\n", sha1_to_hex(tree1->object.sha1),
+			  sha1_to_hex(tree2->object.sha1));
+	diff_tree_sha1(tree1->object.sha1, tree2->object.sha1,
+		       "", &log_tree_opt.diffopt);
+	log_tree_diff_flush(&log_tree_opt);
+	return 0;
+}
+
+static int diff_tree_stdin(char *line)
+{
+	int len = strlen(line);
+	unsigned char sha1[20];
+	struct object *obj;
+
+	if (!len || line[len-1] != '\n')
+		return -1;
+	line[len-1] = 0;
+	if (get_sha1_hex(line, sha1))
+		return -1;
+	obj = lookup_unknown_object(sha1);
+	if (!obj || !obj->parsed)
+		obj = parse_object(sha1);
+	if (!obj)
+		return -1;
+	if (obj->type == OBJ_COMMIT)
+		return stdin_diff_commit((struct commit *)obj, line, len);
+	if (obj->type == OBJ_TREE)
+		return stdin_diff_trees((struct tree *)obj, line, len);
+	error("Object %s is a %s, not a commit or tree",
+	      sha1_to_hex(sha1), typename(obj->type));
+	return -1;
+}
+
+static const char diff_tree_usage[] =
+"git diff-tree [--stdin] [-m] [-c] [--cc] [-s] [-v] [--pretty] [-t] [-r] [--root] "
+"[<common diff options>] <tree-ish> [<tree-ish>] [<path>...]\n"
+"  -r            diff recursively\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, struct setup_revision_opt *opt)
+{
+	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)
+{
+	int nr_sha1;
+	char line[1000];
+	struct object *tree1, *tree2;
+	static struct rev_info *opt = &log_tree_opt;
+	struct setup_revision_opt s_r_opt;
+	int read_stdin = 0;
+
+	init_revisions(opt, prefix);
+	git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
+	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;
+	argc = setup_revisions(argc, argv, opt, &s_r_opt);
+
+	while (--argc > 0) {
+		const char *arg = *++argv;
+
+		if (!strcmp(arg, "--stdin")) {
+			read_stdin = 1;
+			continue;
+		}
+		usage(diff_tree_usage);
+	}
+
+	/*
+	 * NOTE! We expect "a ^b" to be equal to "a..b", so we
+	 * reverse the order of the objects if the second one
+	 * is marked UNINTERESTING.
+	 */
+	nr_sha1 = opt->pending.nr;
+	switch (nr_sha1) {
+	case 0:
+		if (!read_stdin)
+			usage(diff_tree_usage);
+		break;
+	case 1:
+		tree1 = opt->pending.objects[0].item;
+		diff_tree_commit_sha1(tree1->sha1);
+		break;
+	case 2:
+		tree1 = opt->pending.objects[0].item;
+		tree2 = opt->pending.objects[1].item;
+		if (tree2->flags & UNINTERESTING) {
+			struct object *tmp = tree2;
+			tree2 = tree1;
+			tree1 = tmp;
+		}
+		diff_tree_sha1(tree1->sha1,
+			       tree2->sha1,
+			       "", &opt->diffopt);
+		log_tree_diff_flush(opt);
+		break;
+	}
+
+	if (read_stdin) {
+		if (opt->diffopt.detect_rename)
+			opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
+					       DIFF_SETUP_USE_CACHE);
+		while (fgets(line, sizeof(line), stdin)) {
+			unsigned char sha1[20];
+
+			if (get_sha1_hex(line, sha1)) {
+				fputs(line, stdout);
+				fflush(stdout);
+			}
+			else
+				diff_tree_stdin(line);
+		}
+	}
+
+	return diff_result_code(&opt->diffopt, 0);
+}