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

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
This commit is contained in:
Junio C Hamano
2014-01-27 10:45:33 -08:00
6 changed files with 155 additions and 67 deletions

27
dir.c
View File

@ -1511,8 +1511,13 @@ static int remove_dir_recurse(struct strbuf *path, int flag, int *kept_up)
flag &= ~REMOVE_DIR_KEEP_TOPLEVEL;
dir = opendir(path->buf);
if (!dir) {
/* an empty dir could be removed even if it is unreadble */
if (!keep_toplevel)
if (errno == ENOENT)
return keep_toplevel ? -1 : 0;
else if (errno == EACCES && !keep_toplevel)
/*
* An empty dir could be removable even if it
* is unreadable:
*/
return rmdir(path->buf);
else
return -1;
@ -1528,13 +1533,21 @@ static int remove_dir_recurse(struct strbuf *path, int flag, int *kept_up)
strbuf_setlen(path, len);
strbuf_addstr(path, e->d_name);
if (lstat(path->buf, &st))
; /* fall thru */
else if (S_ISDIR(st.st_mode)) {
if (lstat(path->buf, &st)) {
if (errno == ENOENT)
/*
* file disappeared, which is what we
* wanted anyway
*/
continue;
/* fall thru */
} else if (S_ISDIR(st.st_mode)) {
if (!remove_dir_recurse(path, flag, &kept_down))
continue; /* happy */
} else if (!only_empty && !unlink(path->buf))
} else if (!only_empty &&
(!unlink(path->buf) || errno == ENOENT)) {
continue; /* happy, too */
}
/* path too long, stat fails, or non-directory still exists */
ret = -1;
@ -1544,7 +1557,7 @@ static int remove_dir_recurse(struct strbuf *path, int flag, int *kept_up)
strbuf_setlen(path, original_len);
if (!ret && !keep_toplevel && !kept_down)
ret = rmdir(path->buf);
ret = (!rmdir(path->buf) || errno == ENOENT) ? 0 : -1;
else if (kept_up)
/*
* report the uplevel that it is not an error that we