git/refs.c, branch v2.0.0

Merge branch 'sh/use-hashcpy'

2014-03-18T20:51:05Z

* sh/use-hashcpy: Use hashcpy() when copying object names

Use hashcpy() when copying object names

2014-03-06T22:03:12Z

We invented hashcpy() to keep the abstraction of "object name" behind it. Use it instead of calling memcpy() with hard-coded 20-byte length when moving object names between pieces of memory. Leave ppc/sha1.c as-is, because the function is about the SHA-1 hash algorithm whose output is and will always be 20 bytes. Helped-by: Michael Haggerty Helped-by: Duy Nguyen Signed-off-by: Sun He Signed-off-by: Junio C Hamano

use wildmatch() directly without fnmatch() wrapper

2014-02-20T22:15:46Z

Make it clear that we don't use fnmatch() anymore. Signed-off-by: Nguyễn Thái Ngọc Duy Signed-off-by: Junio C Hamano

Merge branch 'mh/safe-create-leading-directories'

2014-01-27T18:45:33Z

Code clean-up and protection against concurrent write access to the ref namespace. * mh/safe-create-leading-directories: rename_tmp_log(): on SCLD_VANISHED, retry rename_tmp_log(): limit the number of remote_empty_directories() attempts rename_tmp_log(): handle a possible mkdir/rmdir race rename_ref(): extract function rename_tmp_log() remove_dir_recurse(): handle disappearing files and directories remove_dir_recurse(): tighten condition for removing unreadable dir lock_ref_sha1_basic(): if locking fails with ENOENT, retry lock_ref_sha1_basic(): on SCLD_VANISHED, retry safe_create_leading_directories(): add new error value SCLD_VANISHED cmd_init_db(): when creating directories, handle errors conservatively safe_create_leading_directories(): introduce enum for return values safe_create_leading_directories(): always restore slash at end of loop safe_create_leading_directories(): split on first of multiple slashes safe_create_leading_directories(): rename local variable safe_create_leading_directories(): add explicit "slash" pointer safe_create_leading_directories(): reduce scope of local variable safe_create_leading_directories(): fix format of "if" chaining

Merge branch 'mh/retire-ref-fetch-rules'

2014-01-27T18:44:07Z

Code simplification. * mh/retire-ref-fetch-rules: refname_match(): always use the rules in ref_rev_parse_rules

rename_tmp_log(): on SCLD_VANISHED, retry

2014-01-21T21:47:28Z

If safe_create_leading_directories() fails because a file along the path unexpectedly vanished, try again from the beginning. Try at most 4 times. Signed-off-by: Michael Haggerty Signed-off-by: Junio C Hamano

rename_tmp_log(): limit the number of remote_empty_directories() attempts

2014-01-21T21:47:24Z

This doesn't seem to be a likely error, but we've got the counter anyway, so we might as well use it for an added bit of safety. Please note that the first call to rename() is optimistic, and it is normal for it to fail if there is a directory in the way. So bump the total number of allowed attempts to 4, to be sure that we can still have at least 3 retries in the case of a race. Signed-off-by: Michael Haggerty Signed-off-by: Junio C Hamano

rename_tmp_log(): handle a possible mkdir/rmdir race

2014-01-21T21:47:13Z

If a directory vanishes while renaming the temporary reflog file, retry (up to 3 times). This could happen if another process deletes the directory created by safe_create_leading_directories() just before we rename the file into the directory. As far as I can tell, this race could not occur internal to git. The only time that a directory under $GIT_DIR/logs is deleted is if room has to be made for a log file for a reference with the same name; for example, in the following sequence: git branch foo/bar # Creates file .git/logs/refs/heads/foo/bar git branch -d foo/bar # Deletes file but leaves .git/logs/refs/heads/foo/ git branch foo # Deletes .git/logs/refs/heads/foo/ But the only reason the last command deletes the directory is because it wants to create a file with the same name. So if another process (e.g., git branch foo/baz ) wants to create that directory, one of the two is doomed to failure anyway because of a D/F conflict. Signed-off-by: Michael Haggerty Signed-off-by: Junio C Hamano

rename_ref(): extract function rename_tmp_log()

2014-01-21T21:46:59Z

It's about to become a bit more complex. Signed-off-by: Michael Haggerty Signed-off-by: Junio C Hamano

lock_ref_sha1_basic(): if locking fails with ENOENT, retry

2014-01-21T21:46:30Z

If hold_lock_file_for_update() fails with errno==ENOENT, it might be because somebody else (for example, a pack-refs process) has just deleted one of the lockfile's ancestor directories. So if this condition is detected, try again (up to 3 times). Signed-off-by: Michael Haggerty Signed-off-by: Junio C Hamano