Patterns such as `.*` or `@*` are matched against an item's own name
with `fnmatch`, in the same places as excluded names: resolving a
tree, extending a watch to a directory that appears later, and
delivering events. Dependents that prune large trees can now skip
whole families of directories without listing each name.
`InotifyEventMask` took its bits from the C header, so nothing that
imported it could build outside Linux. The new `InotifyMask` product
spells out the kernel constants instead; a Linux test compares each
of them with the header. `Inotify` re-exports the module, so
existing code is unaffected.
The resolver skipped an excluded directory in its result but still
walked its subtree, so watches were installed below names such as
`.git` or `node_modules`. Exclusion now prunes the walk.
Automatic subtree watching only reacted to `CREATE`, so a directory
moved in from elsewhere stayed unwatched. It is now handled like a
created one. Items that already exist in such a directory never
produce kernel events; they are reported with the same event kind
and `synthesized` set to `true`, so consumers can treat them as
newly appeared.
A directory moved out of a watched tree kept its kernel watches, so
later changes inside it were reported under the old path. Its
watches and those of its subdirectories are now removed on
`MOVED_FROM`. Watches the kernel reports as `IGNORED` are forgotten
as well, so a reused descriptor number cannot map to a stale path.
`IN_Q_OVERFLOW` arrives with watch descriptor -1, so the path lookup
failed and the event was silently discarded. It is now delivered
with an empty path so consumers can rescan after the kernel dropped
events.
The limits were only written back after a successful body, so a
failing limit test left the shared kernel at the lowered values and
every later run failed with ENOSPC. The helper now restores in a
`defer` and can lower a chosen subset of the limits.
Events were buffered with `bufferingNewest(512)`, so a burst of
changes silently lost all but the newest 512 events whenever the
consumer lagged. The stream now buffers without limit, and
`init(bufferingPolicy:)` lets callers choose a bounded policy.
`deinit` closed the inotify descriptor while its dispatch source was
still active. The kernel drops the epoll registration on close, but
libdispatch keeps its own; an instance created afterwards that reuses
the descriptor number could inherit that stale state and never
receive events. Roughly one test run in three lost a single event
this way.
The reader is now cancelled in `deinit` and the descriptor closed in
its cancel handler, as libdispatch requires.
The exclusive `from: "0.3.0"` range blocked dependents that already
use swift-subprocess 1.0. Version 1.0 renamed the stdio outputs used
by the task CLI to `currentStandardOutput` and `currentStandardError`.
Properties of actors are implicitly isolated. To be able to read the
events stream from any concurrent context, we need to declare it
nonisolated. And as AsyncStream conforms to Sendable, it is safe to make
both events and the private eventStream nonisolated.
Drop Shwift: it is incompatible with musl (used by the Swift static
linking SDK), and its API is not meaningfully more concise than
Subprocess upon closer inspection.
SwiftPM has currently a bug, that products or targets of dependencies
are taken into consideration when resolving names, regardless if they're
used or not by the root package. This stops Swift PM from working on packages,
that declare this package as a dependency and define their own TaskCLI target,
as they collide with the definitions of this package. This is resolved, by
prefixing TaskCLI with the package name.
The product collision - which causes swift run - to run this package's task
executable is resolved, by adding that product only temporarily during task
execution using task.sh.
See https://github.com/swiftlang/swift-package-manager/issues/8482
inotify exposes a /proc interface to limit kernel memory usage. If those
limits are set too low, inotify cannot add all watches. The integration
test verifies, that Inotify yields an error in that case.
For watching whole trees - a change which is upcoming - the watch
descriptor IDs will have to be managed in multiple lists. The
InotifyWatchManager encapsulates the managment logic within a nice API.
Instead of using hardcoded fixed width integers, use C integer types.
As the actual integer size of C depends on the implementation, even if
it is often 32bit, we use the C integer types to guard against cases,
where that is not the case.
Each inotify instance produces events for paths in its watch list. Each
item in the watch list is identified by its watch descriptor. Different
paths can be watched for different events.
T. R. Bernstein