Following commit 2e3685f217,
make sure all backends check this flag and return correct error codes.
Normally this is not mandatory, since the kernel looks up
the directory entry to be removed, and fails if the system call
is inappropriate (e.g., calling rmdir() on a regular file).
This happens before FUSE_UNLINK or FUSE_RMDIR is sent to the server.
However, when not in exclusive mode, there is a short window that
TOCTOU problem may occur, which may lead to undesired behavior
(e.g., deletion of a non-empty directory) or even the corruption of
bookmark storage if not properly checked.
Also explain this flag in the user manual.
- Do not exit with status 99. It is considered a "hard failure"
in Autotest, and cleanup script won't be executed.
- Fix ATX_FEAT_PREREQ().
- Remove unneeded helper macros.
- Add more log output.
In readonly mode, we're not using the current time as timestamp,
thus a bad system time won't hurt.
Also in Chromium backend, use zero timestamp for the bookmark root
dir, to accomodate this change (no one cares about it anyway).
When updating timestamps, make sure that the corresponding
microsecond value fits in a single signed 64-bit integer,
so that it won't result in an integer overflow, which is UB.
Also forbid timestamps before the Unix epoch, since working with
negative time_t is problematic.
This check does not apply to current timestamp, however,
add a check on backend startup to ensure sane system time.
There's no need to validate `tv_nsec`, since the kernel already
does that for us.
Do not expose UTIME_OMIT to backends, but instead specify
which timestamps to update with flags.
This allows us to further refactor backend code, especially
the Chromium backend.
- Follow the "best practice" in the SQLite manual, where calls to
sqlite3_column_bytes() should come after sqlite3_column_text().
This change does not affect the values returned.
- Other misc updates.
If a bookmark is assigned SYNC_STATUS_NORMAL (value 2),
a "tombstone" has to be inserted upon deletion,
so that the browser could purge it from remote.
- `hashmap_insert()` no longer takes key as argument, and
takes the pointer to be associated with the entry as argument.
- Rename `hashmap_entry_delete` -> `hashmap_delete`.
- Make `user_data` the first argument for `hashmap_walk_func`.
- Other misc renames.
That part of code in configure.ac look stupid, remove it.
If we _do_ try to run BookmarkFS on such an exotic platform with
non-zero null pointers, the breakage should be detected by the tests
(if it can run or even build at all).
This is meant to be a workaround for a limitation of Autotest,
where `set -e` has no effect in AT_CHECK().
Also we don't want to use `trap ... ERR`, since it is not portable.
- Workaround a glibc issue for filtering negative syscall arguments.
- Allow unlinkat() syscall.
- Add extra filter for openat() in read-only mode when Landlock
is not available.
