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[PATCH v3 7/8] fetch: fetch objects by their exact SHA-1 object names

From
Junio C Hamano <gitster@pobox.com>
Date
Jan 30, 2013, 18:45 UTC
Message-ID
<1359571542-19852-8-git-send-email-gitster@pobox.com>
In-Reply-To
<1359571542-19852-1-git-send-email-gitster@pobox.com>

Teach "git fetch" to accept an exact SHA-1 object name the user may obtain out of band on the LHS of a pathspec, and send it on a "want" message when the server side advertises the allow-tip-sha1-in-want capability.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 fetch-pack.c          | 22 +++++++++++++++++++++-
 remote.c              | 12 +++++++++++-
 remote.h              |  1 +
 t/t5516-fetch-push.sh | 34 ++++++++++++++++++++++++++++++++++
 4 files changed, 67 insertions(+), 2 deletions(-)
diff --git a/fetch-pack.c b/fetch-pack.c
index 915c0b7..70db646 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -36,7 +36,7 @@ static int marked;
 #define MAX_IN_VAIN 256
 
 static struct commit_list *rev_list;
-static int non_common_revs, multi_ack, use_sideband;
+static int non_common_revs, multi_ack, use_sideband, allow_tip_sha1_in_want;
 
 static void rev_list_push(struct commit *commit, int mark)
 {
@@ -563,6 +563,21 @@ static void filter_refs(struct fetch_pack_args *args,
 		}
 	}
 
+	/* Append unmatched requests to the list */
+	if (allow_tip_sha1_in_want) {
+		for (i = 0; i < nr_sought; i++) {
+			ref = sought[i];
+			if (ref->matched)
+				continue;
+			if (get_sha1_hex(ref->name, ref->old_sha1))
+				continue;
+
+			ref->matched = 1;
+			*newtail = ref;
+			ref->next = NULL;
+			newtail = &ref->next;
+		}
+	}
 	*refs = newlist;
 }
 
@@ -803,6 +818,11 @@ static struct ref *do_fetch_pack(struct fetch_pack_args *args,
 			fprintf(stderr, "Server supports side-band\n");
 		use_sideband = 1;
 	}
+	if (server_supports("allow-tip-sha1-in-want")) {
+		if (args->verbose)
+			fprintf(stderr, "Server supports allow-tip-sha1-in-want\n");
+		allow_tip_sha1_in_want = 1;
+	}
 	if (!server_supports("thin-pack"))
 		args->use_thin_pack = 0;
 	if (!server_supports("no-progress"))
diff --git a/remote.c b/remote.c
index 1b7828d..1118d05 100644
--- a/remote.c
+++ b/remote.c
@@ -15,6 +15,7 @@ static struct refspec s_tag_refspec = {
 	0,
 	1,
 	0,
+	0,
 	"refs/tags/*",
 	"refs/tags/*"
 };
@@ -565,9 +566,13 @@ static struct refspec *parse_refspec_internal(int nr_refspec, const char **refsp
 		flags = REFNAME_ALLOW_ONELEVEL | (is_glob ? REFNAME_REFSPEC_PATTERN : 0);
 
 		if (fetch) {
+			unsigned char unused[40];
+
 			/* LHS */
 			if (!*rs[i].src)
 				; /* empty is ok; it means "HEAD" */
+			else if (llen == 40 && !get_sha1_hex(rs[i].src, unused))
+				rs[i].exact_sha1 = 1; /* ok */
 			else if (!check_refname_format(rs[i].src, flags))
 				; /* valid looking ref is ok */
 			else
@@ -1495,7 +1500,12 @@ int get_fetch_map(const struct ref *remote_refs,
 	} else {
 		const char *name = refspec->src[0] ? refspec->src : "HEAD";
 
-		ref_map = get_remote_ref(remote_refs, name);
+		if (refspec->exact_sha1) {
+			ref_map = alloc_ref(name);
+			get_sha1_hex(name, ref_map->old_sha1);
+		} else {
+			ref_map = get_remote_ref(remote_refs, name);
+		}
 		if (!missing_ok && !ref_map)
 			die("Couldn't find remote ref %s", name);
 		if (ref_map) {
diff --git a/remote.h b/remote.h
index 251d8fd..f7b08f1 100644
--- a/remote.h
+++ b/remote.h
@@ -62,6 +62,7 @@ struct refspec {
 	unsigned force : 1;
 	unsigned pattern : 1;
 	unsigned matching : 1;
+	unsigned exact_sha1 : 1;
 
 	char *src;
 	char *dst;
diff --git a/t/t5516-fetch-push.sh b/t/t5516-fetch-push.sh
index 852efb6..522056f 100755
--- a/t/t5516-fetch-push.sh
+++ b/t/t5516-fetch-push.sh
@@ -1037,6 +1037,40 @@ test_expect_success 'push --prune refspec' '
 	! check_push_result $the_first_commit tmp/foo tmp/bar
 '
 
+test_expect_success 'fetch exact SHA1' '
+	mk_test heads/master hidden/one &&
+	git push testrepo master:refs/hidden/one &&
+	(
+		cd testrepo &&
+		git config transfer.hiderefs refs/hidden
+	) &&
+	check_push_result $the_commit hidden/one &&
+
+	mk_child child &&
+	(
+		cd child &&
+
+		# make sure $the_commit does not exist here
+		git repack -a -d &&
+		git prune &&
+		test_must_fail git cat-file -t $the_commit &&
+
+		# fetching the hidden object should fail by default
+		test_must_fail git fetch -v ../testrepo $the_commit:refs/heads/copy &&
+		test_must_fail git rev-parse --verify refs/heads/copy &&
+
+		# the server side can allow it to succeed
+		(
+			cd ../testrepo &&
+			git config uploadpack.allowtipsha1inwant true
+		) &&
+
+		git fetch -v ../testrepo $the_commit:refs/heads/copy &&
+		result=$(git rev-parse --verify refs/heads/copy) &&
+		test "$the_commit" = "$result"
+	)
+'
+
 test_expect_success 'push to update a hidden ref' '
 	mk_test heads/master hidden/one hidden/two hidden/three &&
 	(
-- 
1.8.1.2.589.ga9b91ac
Previous: Junio C HamanoNext: Jeff King
Message 12 of 54 in “Hiding refs”
  1. 0/8 Hiding refsJunio C Hamano, Jan 30, 2013
  2. 1/8 upload-pack: share more codeJunio C Hamano, Jan 30, 2013
  3. 2/8 upload-pack: simplify request validationJunio C Hamano, Jan 30, 2013
  4. 3/8 upload/receive-pack: allow hiding ref hierarchiesJunio C Hamano, Jan 30, 2013
  5. Jeff KingFeb 5, 2013
  6. Junio C HamanoFeb 5, 2013
  7. Jeff KingFeb 6, 2013
  8. Junio C HamanoFeb 6, 2013
  9. 4/8 parse_fetch_refspec(): clarify the codeflow a bitJunio C Hamano, Jan 30, 2013
  10. 5/8 fetch: use struct ref to represent refs to be fetchedJunio C Hamano, Jan 30, 2013
  11. 6/8 upload-pack: optionally allow fetching from the tips of hidden refsJunio C Hamano, Jan 30, 2013
  12. 7/8 fetch: fetch objects by their exact SHA-1 object namesJunio C Hamano, Jan 30, 2013
  13. Jeff KingFeb 5, 2013
  14. Jeff KingFeb 5, 2013
  15. Junio C HamanoFeb 5, 2013
  16. 8/8 WIP: receive.allowupdatestohiddenJunio C Hamano, Jan 30, 2013
  17. Michael HaggertyFeb 5, 2013
  18. Jonathan NiederFeb 5, 2013
  19. Michael HaggertyFeb 5, 2013
  20. Junio C HamanoFeb 5, 2013
  21. Duy NguyenFeb 6, 2013
  22. Junio C HamanoFeb 6, 2013
  23. Jonathan NiederFeb 6, 2013
  24. Michael HaggertyFeb 6, 2013
  25. Junio C HamanoFeb 6, 2013
  26. Ævar Arnfjörð BjarmasonFeb 6, 2013
  27. Junio C HamanoFeb 7, 2013
  28. Jeff KingFeb 7, 2013
  29. Ævar Arnfjörð BjarmasonFeb 7, 2013
  30. Junio C HamanoFeb 7, 2013
  31. Duy NguyenFeb 23, 2014
  32. Jeff KingMar 11, 2014
  33. Junio C HamanoMar 11, 2014
  34. Jeff KingMar 11, 2014
  35. Junio C HamanoMar 11, 2014
  36. Jeff KingMar 11, 2014
  37. Duy NguyenMar 14, 2014
  38. Shawn PearceMar 14, 2014
  39. Duy NguyenMar 14, 2014
  40. Shawn PearceMar 15, 2014
  41. Jeff KingMar 18, 2014
  42. Duy NguyenMar 18, 2014
  43. Duy NguyenMar 18, 2014
  44. Duy NguyenMar 15, 2014
  45. Jeff KingMar 18, 2014
  46. Jeff KingFeb 6, 2013
  47. Junio C HamanoFeb 5, 2013
  48. Junio C HamanoFeb 5, 2013
  49. Michael HaggertyFeb 6, 2013
  50. Jonathan NiederFeb 6, 2013
  51. Michael HaggertyFeb 6, 2013
  52. Jed BrownFeb 7, 2013
  53. Junio C HamanoFeb 9, 2013
  54. Jed BrownFeb 10, 2013

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