git/refs, branch v2.10.2

files_read_raw_ref: prevent infinite retry loops in general

2016-10-10T17:53:33Z

Limit the number of retries to 3. That should be adequate to prevent any races, while preventing the possibility of infinite loops if the logic fails to handle any other possible error modes correctly. After the fix in the previous commit, there's no known way to trigger an infinite loop, but I did manually verify that this fixes the test in that commit even when the code change is not applied. Signed-off-by: Jeff King Reviewed-by: Michael Haggerty Signed-off-by: Junio C Hamano

files_read_raw_ref: avoid infinite loop on broken symlinks

2016-10-10T17:53:16Z

Our ref resolution first runs lstat() on any path we try to look up, because we want to treat symlinks specially (by resolving them manually and considering them symrefs). But if the results of `readlink` do _not_ look like a ref, we fall through to treating it like a normal file, and just read the contents of the linked path. Since fcb7c76 (resolve_ref_unsafe(): close race condition reading loose refs, 2013-06-19), that "normal file" code path will stat() the file and if we see ENOENT, will jump back to the lstat(), thinking we've seen inconsistent results between the two calls. But for a symbolic ref, this isn't a race: the lstat() found the symlink, and the stat() is looking at the path it points to. We end up in an infinite loop calling lstat() and stat(). We can fix this by avoiding the retry-on-inconsistent jump when we know that we found a symlink. While we're at it, let's add a comment explaining why the symlink case gets to this code in the first place; without that, it is not obvious that the correct solution isn't to avoid the stat() code path entirely. Signed-off-by: Jeff King Reviewed-by: Michael Haggerty Signed-off-by: Junio C Hamano

Merge branch 'mh/ref-iterators'

2016-07-25T21:13:33Z

The API to iterate over all the refs (i.e. for_each_ref(), etc.) has been revamped. * mh/ref-iterators: for_each_reflog(): reimplement using iterators dir_iterator: new API for iterating over a directory tree for_each_reflog(): don't abort for bad references do_for_each_ref(): reimplement using reference iteration refs: introduce an iterator interface ref_resolves_to_object(): new function entry_resolves_to_object(): rename function from ref_resolves_to_object() get_ref_cache(): only create an instance if there is a submodule remote rm: handle symbolic refs correctly delete_refs(): add a flags argument refs: use name "prefix" consistently do_for_each_ref(): move docstring to the header file refs: remove unnecessary "extern" keywords

Merge branch 'mh/update-ref-errors'

2016-07-25T21:13:33Z

Error handling in the codepaths that updates refs has been improved. * mh/update-ref-errors: lock_ref_for_update(): avoid a symref resolution lock_ref_for_update(): make error handling more uniform t1404: add more tests of update-ref error handling t1404: document function test_update_rejected t1404: remove "prefix" argument to test_update_rejected t1404: rename file to t1404-update-ref-errors.sh

Merge branch 'mh/split-under-lock'

2016-07-25T21:13:32Z

Further preparatory work on the refs API before the pluggable backend series can land. * mh/split-under-lock: (33 commits) lock_ref_sha1_basic(): only handle REF_NODEREF mode commit_ref_update(): remove the flags parameter lock_ref_for_update(): don't resolve symrefs lock_ref_for_update(): don't re-read non-symbolic references refs: resolve symbolic refs first ref_transaction_update(): check refname_is_safe() at a minimum unlock_ref(): move definition higher in the file lock_ref_for_update(): new function add_update(): initialize the whole ref_update verify_refname_available(): adjust constness in declaration refs: don't dereference on rename refs: allow log-only updates delete_branches(): use resolve_refdup() ref_transaction_commit(): correctly report close_ref() failure ref_transaction_create(): disallow recursive pruning refs: make error messages more consistent lock_ref_sha1_basic(): remove unneeded local variable read_raw_ref(): move docstring to header file read_raw_ref(): improve docstring read_raw_ref(): rename symref argument to referent ...

coccinelle: apply object_id Coccinelle transformations

2016-06-28T18:39:02Z

Apply the set of semantic patches from contrib/coccinelle to convert some leftover places using struct object_id's hash member to instead use the wrapper functions that take struct object_id natively. Signed-off-by: brian m. carlson Signed-off-by: Junio C Hamano

lock_ref_for_update(): avoid a symref resolution

2016-06-20T18:49:00Z

If we're overwriting a symref with a SHA-1, we need to resolve the value of the symref (1) to check against update->old_sha1 and (2) to write to its reflog. However, we've already read the symref itself and know its referent. So there is no need to read the symref's value through the symref; we can read the referent directly. Signed-off-by: Michael Haggerty Signed-off-by: Junio C Hamano

lock_ref_for_update(): make error handling more uniform

2016-06-20T18:49:00Z

To aid the effort, extract a new function, check_old_oid(), and use it in the two places where the read value of the reference has to be checked against update->old_sha1. Update tests to reflect the improvements. Signed-off-by: Michael Haggerty Signed-off-by: Junio C Hamano

for_each_reflog(): reimplement using iterators

2016-06-20T18:38:21Z

Allow references with reflogs to be iterated over using a ref_iterator. The latter is implemented as a files_reflog_iterator, which in turn uses dir_iterator to read the "logs" directory. Note that reflog iteration doesn't correctly handle per-worktree reflogs (either before or after this patch). Signed-off-by: Ramsay Jones Signed-off-by: Michael Haggerty Signed-off-by: Junio C Hamano

for_each_reflog(): don't abort for bad references

2016-06-20T18:38:20Z

If there is a file under "$GIT_DIR/logs" with no corresponding reference, the old code was emitting an error message, aborting the reflog iteration, and returning -1. But * None of the callers was checking the exit value * The callers all want to find all legitimate reflogs (sometimes for the purpose of determining object reachability!) and wouldn't benefit from a truncated iteration anyway. So instead, emit an error message and skip the "broken" reflog, but continue with the iteration. Signed-off-by: Michael Haggerty Signed-off-by: Junio C Hamano