git/list[1] front-page[2] threads[3] people[4] search[5] about
 

[PATCH v18 45/48] refs.c: pass a skip list to name_conflict_fn

From
Ronnie Sahlberg <sahlberg@google.com>
Date
Jun 17, 2014, 15:53 UTC
Message-ID
<1403020442-31049-46-git-send-email-sahlberg@google.com>
In-Reply-To
<1403020442-31049-1-git-send-email-sahlberg@google.com>

Allow passing a list of refs to skip checking to name_conflict_fn. There are some conditions where we want to allow a temporary conflict and skip checking those refs. For example if we have a transaction that 1, guarantees that m is a packed refs and there is no loose ref for m 2, the transaction will delete m from the packed ref 3, the transaction will create conflicting m/m

For this case we want to be able to lock and create m/m since we know that the conflict is only transient. I.e. the conflict will be automatically resolved by the transaction when it deletes m.

Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
---
 refs.c | 41 ++++++++++++++++++++++++++---------------
 1 file changed, 26 insertions(+), 15 deletions(-)
diff --git a/refs.c b/refs.c
index 610e063..0e29fb4 100644
--- a/refs.c
+++ b/refs.c
@@ -801,15 +801,18 @@ static int names_conflict(const char *refname1, const char *refname2)
 
 struct name_conflict_cb {
 	const char *refname;
-	const char *oldrefname;
 	const char *conflicting_refname;
+	const char **skip;
+	int skipnum;
 };
 
 static int name_conflict_fn(struct ref_entry *entry, void *cb_data)
 {
 	struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
-	if (data->oldrefname && !strcmp(data->oldrefname, entry->name))
-		return 0;
+	int i;
+	for (i = 0; i < data->skipnum; i++)
+		if (!strcmp(entry->name, data->skip[i]))
+			return 0;
 	if (names_conflict(data->refname, entry->name)) {
 		data->conflicting_refname = entry->name;
 		return 1;
@@ -822,15 +825,18 @@ static int name_conflict_fn(struct ref_entry *entry, void *cb_data)
  * conflicting with the name of an existing reference in dir.  If
  * oldrefname is non-NULL, ignore potential conflicts with oldrefname
  * (e.g., because oldrefname is scheduled for deletion in the same
- * operation).
+ * operation). skip contains a list of refs we want to skip checking for
+ * conflicts with.
  */
-static int is_refname_available(const char *refname, const char *oldrefname,
-				struct ref_dir *dir)
+static int is_refname_available(const char *refname,
+				struct ref_dir *dir,
+				const char **skip, int skipnum)
 {
 	struct name_conflict_cb data;
 	data.refname = refname;
-	data.oldrefname = oldrefname;
 	data.conflicting_refname = NULL;
+	data.skip = skip;
+	data.skipnum = skipnum;
 
 	sort_ref_dir(dir);
 	if (do_for_each_entry_in_dir(dir, 0, name_conflict_fn, &data)) {
@@ -2078,7 +2084,8 @@ int dwim_log(const char *str, int len, unsigned char *sha1, char **log)
 /* This function should make sure errno is meaningful on error */
 static struct ref_lock *lock_ref_sha1_basic(const char *refname,
 					    const unsigned char *old_sha1,
-					    int flags, int *type_p)
+					    int flags, int *type_p,
+					    const char **skip, int skipnum)
 {
 	char *ref_file;
 	const char *orig_refname = refname;
@@ -2127,7 +2134,8 @@ static struct ref_lock *lock_ref_sha1_basic(const char *refname,
 	 * name is a proper prefix of our refname.
 	 */
 	if (missing &&
-	     !is_refname_available(refname, NULL, get_packed_refs(&ref_cache))) {
+	     !is_refname_available(refname, get_packed_refs(&ref_cache),
+				   skip, skipnum)) {
 		last_errno = ENOTDIR;
 		goto error_return;
 	}
@@ -2185,7 +2193,7 @@ struct ref_lock *lock_any_ref_for_update(const char *refname,
 					 const unsigned char *old_sha1,
 					 int flags, int *type_p)
 {
-	return lock_ref_sha1_basic(refname, old_sha1, flags, type_p);
+	return lock_ref_sha1_basic(refname, old_sha1, flags, type_p, NULL, 0);
 }
 
 /*
@@ -2677,10 +2685,12 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms
 	if (!symref)
 		return error("refname %s not found", oldrefname);
 
-	if (!is_refname_available(newrefname, oldrefname, get_packed_refs(&ref_cache)))
+	if (!is_refname_available(newrefname, get_packed_refs(&ref_cache),
+				  &oldrefname, 1))
 		return 1;
 
-	if (!is_refname_available(newrefname, oldrefname, get_loose_refs(&ref_cache)))
+	if (!is_refname_available(newrefname, get_loose_refs(&ref_cache),
+				  &oldrefname, 1))
 		return 1;
 
 	if (log && rename(git_path("logs/%s", oldrefname), git_path(TMP_RENAMED_LOG)))
@@ -2710,7 +2720,7 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms
 
 	logmoved = log;
 
-	lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL);
+	lock = lock_ref_sha1_basic(newrefname, NULL, 0, NULL, NULL, 0);
 	if (!lock) {
 		error("unable to lock %s for update", newrefname);
 		goto rollback;
@@ -2725,7 +2735,7 @@ int rename_ref(const char *oldrefname, const char *newrefname, const char *logms
 	return 0;
 
  rollback:
-	lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL);
+	lock = lock_ref_sha1_basic(oldrefname, NULL, 0, NULL, NULL, 0);
 	if (!lock) {
 		error("unable to lock %s for rollback", oldrefname);
 		goto rollbacklog;
@@ -3601,7 +3611,8 @@ int ref_transaction_commit(struct ref_transaction *transaction,
 						    update->old_sha1 :
 						    NULL),
 						   update->flags,
-						   &update->type);
+						   &update->type,
+						   delnames, delnum);
 		if (!update->lock) {
 			if (err)
 				strbuf_addf(err, "Cannot lock the ref '%s'.",

-- 
2.0.0.438.gec92e5c
Previous: Ronnie SahlbergNext: Ronnie Sahlberg
Message 58 of 61 in “Use ref transactions”
  1. 00/48 Use ref transactionsRonnie Sahlberg, Jun 17, 2014
  2. 01/48 refs.c: remove ref_transaction_rollbackRonnie Sahlberg, Jun 17, 2014
  3. 02/48 refs.c: ref_transaction_commit should not free the transactionRonnie Sahlberg, Jun 17, 2014
  4. 03/48 refs.c: constify the sha arguments for ref_transaction_create|delete|updateRonnie Sahlberg, Jun 17, 2014
  5. 04/48 refs.c: allow passing NULL to ref_transaction_freeRonnie Sahlberg, Jun 17, 2014
  6. 05/48 refs.c: add a strbuf argument to ref_transaction_commit for error loggingRonnie Sahlberg, Jun 17, 2014
  7. 06/48 lockfile.c: add a new public function unable_to_lock_messageRonnie Sahlberg, Jun 17, 2014
  8. 07/48 lockfile.c: make lock_file return a meaningful errno on failureiRonnie Sahlberg, Jun 17, 2014
  9. Michael HaggertyJun 18, 2014
  10. Michael HaggertyJun 18, 2014
  11. 08/48 refs.c: add an err argument to repack_without_refsRonnie Sahlberg, Jun 17, 2014
  12. 09/48 refs.c: make sure log_ref_setup returns a meaningful errnoRonnie Sahlberg, Jun 17, 2014
  13. 10/48 refs.c: verify_lock should set errno to something meaningfulRonnie Sahlberg, Jun 17, 2014
  14. Michael HaggertyJun 18, 2014
  15. Ronnie SahlbergJun 18, 2014
  16. 11/48 refs.c: make remove_empty_directories alwasy set errno to something saneRonnie Sahlberg, Jun 17, 2014
  17. Michael HaggertyJun 18, 2014
  18. Ronnie SahlbergJun 18, 2014
  19. 12/48 refs.c: commit_packed_refs to return a meaningful errno on failureRonnie Sahlberg, Jun 17, 2014
  20. 13/48 refs.c: make resolve_ref_unsafe set errno to something meaningful on errorRonnie Sahlberg, Jun 17, 2014
  21. 14/48 refs.c: log_ref_write should try to return meaningful errnoRonnie Sahlberg, Jun 17, 2014
  22. Michael HaggertyJun 18, 2014
  23. Ronnie SahlbergJun 18, 2014
  24. 15/48 refs.c: make ref_update_reject_duplicates take a strbuf argument for errorsRonnie Sahlberg, Jun 17, 2014
  25. 16/48 refs.c: add an err argument to delete_ref_looseRonnie Sahlberg, Jun 17, 2014
  26. Michael HaggertyJun 18, 2014
  27. Ronnie SahlbergJun 18, 2014
  28. Michael HaggertyJun 18, 2014
  29. Ronnie SahlbergJun 19, 2014
  30. 17/48 refs.c: make update_ref_write update a strbuf on failureRonnie Sahlberg, Jun 17, 2014
  31. 18/48 update-ref: use err argument to get error from ref_transaction_commitRonnie Sahlberg, Jun 17, 2014
  32. 19/48 refs.c: remove the onerr argument to ref_transaction_commitRonnie Sahlberg, Jun 17, 2014
  33. 20/48 refs.c: change ref_transaction_update() to do error checking and return statusRonnie Sahlberg, Jun 17, 2014
  34. 21/48 refs.c: change ref_transaction_create to do error checking and return statusRonnie Sahlberg, Jun 17, 2014
  35. 22/48 refs.c: update ref_transaction_delete to check for error and return statusRonnie Sahlberg, Jun 17, 2014
  36. 23/48 refs.c: make ref_transaction_begin take an err argumentRonnie Sahlberg, Jun 17, 2014
  37. 24/48 refs.c: add transaction.status and track OPEN/CLOSED/ERRORRonnie Sahlberg, Jun 17, 2014
  38. 25/48 tag.c: use ref transactions when doing updatesRonnie Sahlberg, Jun 17, 2014
  39. 26/48 replace.c: use the ref transaction functions for updatesRonnie Sahlberg, Jun 17, 2014
  40. 27/48 commit.c: use ref transactions for updatesRonnie Sahlberg, Jun 17, 2014
  41. 28/48 sequencer.c: use ref transactions for all ref updatesRonnie Sahlberg, Jun 17, 2014
  42. 29/48 fast-import.c: change update_branch to use ref transactionsRonnie Sahlberg, Jun 17, 2014
  43. 30/48 branch.c: use ref transaction for all ref updatesRonnie Sahlberg, Jun 17, 2014
  44. 31/48 refs.c: change update_ref to use a transactionRonnie Sahlberg, Jun 17, 2014
  45. 32/48 receive-pack.c: use a reference transaction for updating the refsRonnie Sahlberg, Jun 17, 2014
  46. 33/48 fast-import.c: use a ref transaction when dumping tagsRonnie Sahlberg, Jun 17, 2014
  47. 34/48 walker.c: use ref transaction for ref updatesRonnie Sahlberg, Jun 17, 2014
  48. 35/48 refs.c: make lock_ref_sha1 staticRonnie Sahlberg, Jun 17, 2014
  49. 36/48 refs.c: remove the update_ref_lock functionRonnie Sahlberg, Jun 17, 2014
  50. 37/48 refs.c: remove the update_ref_write functionRonnie Sahlberg, Jun 17, 2014
  51. 38/48 refs.c: remove lock_ref_sha1Ronnie Sahlberg, Jun 17, 2014
  52. 39/48 refs.c: make prune_ref use a transaction to delete the refRonnie Sahlberg, Jun 17, 2014
  53. 40/48 refs.c: make delete_ref use a transactionRonnie Sahlberg, Jun 17, 2014
  54. 41/48 refs.c: pass the ref log message to _create/delete/update instead of _commitRonnie Sahlberg, Jun 17, 2014
  55. 42/48 refs.c: pass NULL as *flags to read_ref_fullRonnie Sahlberg, Jun 17, 2014
  56. 43/48 refs.c: move the check for valid refname to lock_ref_sha1_basicRonnie Sahlberg, Jun 17, 2014
  57. 44/48 refs.c: call lock_ref_sha1_basic directly from commitRonnie Sahlberg, Jun 17, 2014
  58. 45/48 refs.c: pass a skip list to name_conflict_fnRonnie Sahlberg, Jun 17, 2014
  59. 46/48 refs.c: propagate any errno==ENOTDIR from _commit back to the callersRonnie Sahlberg, Jun 17, 2014
  60. 47/48 fetch.c: change s_update_ref to use a ref transactionRonnie Sahlberg, Jun 17, 2014
  61. 48/48 refs.c: make write_ref_sha1 staticRonnie Sahlberg, Jun 17, 2014

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.