--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/third_party/libuv/src/unix/kqueue.c	Wed Jan 14 19:39:52 2026 -0800
@@ -0,0 +1,667 @@
+/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "uv.h"
+#include "internal.h"
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <sys/sysctl.h>
+#include <sys/types.h>
+#include <sys/event.h>
+#include <sys/time.h>
+#if defined(__FreeBSD__)
+#include <sys/user.h>
+#endif
+#include <unistd.h>
+#include <fcntl.h>
+#include <time.h>
+
+/*
+ * Required on
+ * - Until at least FreeBSD 11.0
+ * - Older versions of Mac OS X
+ *
+ * http://www.boost.org/doc/libs/1_61_0/boost/asio/detail/kqueue_reactor.hpp
+ */
+#ifndef EV_OOBAND
+#define EV_OOBAND  EV_FLAG1
+#endif
+
+static void uv__fs_event(uv_loop_t* loop, uv__io_t* w, unsigned int fflags);
+
+
+int uv__kqueue_init(uv_loop_t* loop) {
+  loop->backend_fd = kqueue();
+  if (loop->backend_fd == -1)
+    return UV__ERR(errno);
+
+  uv__cloexec(loop->backend_fd, 1);
+
+  return 0;
+}
+
+
+#if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 1070
+static _Atomic int uv__has_forked_with_cfrunloop;
+#endif
+
+int uv__io_fork(uv_loop_t* loop) {
+  int err;
+  loop->backend_fd = -1;
+  err = uv__kqueue_init(loop);
+  if (err)
+    return err;
+
+#if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 1070
+  if (loop->cf_state != NULL) {
+    /* We cannot start another CFRunloop and/or thread in the child
+       process; CF aborts if you try or if you try to touch the thread
+       at all to kill it. So the best we can do is ignore it from now
+       on. This means we can't watch directories in the same way
+       anymore (like other BSDs). It also means we cannot properly
+       clean up the allocated resources; calling
+       uv__fsevents_loop_delete from uv_loop_close will crash the
+       process. So we sidestep the issue by pretending like we never
+       started it in the first place.
+    */
+    atomic_store_explicit(&uv__has_forked_with_cfrunloop,
+                          1,
+                          memory_order_relaxed);
+    uv__free(loop->cf_state);
+    loop->cf_state = NULL;
+  }
+#endif /* #if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 1070 */
+  return err;
+}
+
+
+int uv__io_check_fd(uv_loop_t* loop, int fd) {
+  struct kevent ev[2];
+  struct stat sb;
+#ifdef __APPLE__
+  char path[MAXPATHLEN];
+#endif
+
+  if (uv__fstat(fd, &sb))
+    return UV__ERR(errno);
+
+  /* On FreeBSD, kqueue only supports EVFILT_READ notification for regular files
+   * and always reports ready events for writing, resulting in busy-looping.
+   *
+   * On Darwin, DragonFlyBSD, NetBSD and OpenBSD, kqueue reports ready events for
+   * regular files as readable and writable only once, acting like an EV_ONESHOT.
+   * 
+   * Neither of the above cases should be added to the kqueue.
+   */
+  if (S_ISREG(sb.st_mode) || S_ISDIR(sb.st_mode))
+    return UV_EINVAL;
+
+#ifdef __APPLE__
+  /* On Darwin (both macOS and iOS), in addition to regular files, FIFOs also don't
+   * work properly with kqueue: the disconnection from the last writer won't trigger
+   * an event for kqueue in spite of what the man pages say. Thus, we also disallow
+   * the case of S_IFIFO. */ 
+  if (S_ISFIFO(sb.st_mode)) {
+    /* File descriptors of FIFO, pipe and kqueue share the same type of file, 
+     * therefore there is no way to tell them apart via stat.st_mode&S_IFMT.
+     * Fortunately, FIFO is the only one that has a persisted file on filesystem,
+     * from which we're able to make the distinction for it. */
+    if (!fcntl(fd, F_GETPATH, path))
+      return UV_EINVAL;
+  }
+#endif
+
+  EV_SET(ev, fd, EVFILT_READ, EV_ADD, 0, 0, 0);
+  EV_SET(ev + 1, fd, EVFILT_READ, EV_DELETE, 0, 0, 0);
+  if (kevent(loop->backend_fd, ev, 2, NULL, 0, NULL))
+    return UV__ERR(errno);
+
+  return 0;
+}
+
+
+static void uv__kqueue_delete(int kqfd, const struct kevent *ev) {
+  struct kevent change;
+
+  EV_SET(&change, ev->ident, ev->filter, EV_DELETE, 0, 0, 0);
+
+  if (0 == kevent(kqfd, &change, 1, NULL, 0, NULL))
+    return;
+
+  if (errno == EBADF || errno == ENOENT)
+    return;
+
+  abort();
+}
+
+
+void uv__io_poll(uv_loop_t* loop, int timeout) {
+  uv__loop_internal_fields_t* lfields;
+  struct kevent events[1024];
+  struct kevent* ev;
+  struct timespec spec;
+  unsigned int nevents;
+  unsigned int revents;
+  struct uv__queue* q;
+  uv__io_t* w;
+  uv_process_t* process;
+  sigset_t* pset;
+  sigset_t set;
+  uint64_t base;
+  uint64_t diff;
+  int have_signals;
+  int filter;
+  int fflags;
+  int count;
+  int nfds;
+  int fd;
+  int op;
+  int i;
+  int user_timeout;
+  int reset_timeout;
+
+  if (loop->nfds == 0) {
+    assert(uv__queue_empty(&loop->watcher_queue));
+    return;
+  }
+
+  lfields = uv__get_internal_fields(loop);
+  nevents = 0;
+
+  while (!uv__queue_empty(&loop->watcher_queue)) {
+    q = uv__queue_head(&loop->watcher_queue);
+    uv__queue_remove(q);
+    uv__queue_init(q);
+
+    w = uv__queue_data(q, uv__io_t, watcher_queue);
+    assert(w->pevents != 0);
+    assert(w->fd >= 0);
+    assert(w->fd < (int) loop->nwatchers);
+
+    if ((w->events & POLLIN) == 0 && (w->pevents & POLLIN) != 0) {
+      filter = EVFILT_READ;
+      fflags = 0;
+      op = EV_ADD;
+
+      if (w->cb == uv__fs_event) {
+        filter = EVFILT_VNODE;
+        fflags = NOTE_ATTRIB | NOTE_WRITE  | NOTE_RENAME
+               | NOTE_DELETE | NOTE_EXTEND | NOTE_REVOKE;
+        op = EV_ADD | EV_ONESHOT; /* Stop the event from firing repeatedly. */
+      }
+
+      EV_SET(events + nevents, w->fd, filter, op, fflags, 0, 0);
+
+      if (++nevents == ARRAY_SIZE(events)) {
+        if (kevent(loop->backend_fd, events, nevents, NULL, 0, NULL))
+          abort();
+        nevents = 0;
+      }
+    }
+
+    if ((w->events & POLLOUT) == 0 && (w->pevents & POLLOUT) != 0) {
+      EV_SET(events + nevents, w->fd, EVFILT_WRITE, EV_ADD, 0, 0, 0);
+
+      if (++nevents == ARRAY_SIZE(events)) {
+        if (kevent(loop->backend_fd, events, nevents, NULL, 0, NULL))
+          abort();
+        nevents = 0;
+      }
+    }
+
+   if ((w->events & UV__POLLPRI) == 0 && (w->pevents & UV__POLLPRI) != 0) {
+      EV_SET(events + nevents, w->fd, EV_OOBAND, EV_ADD, 0, 0, 0);
+
+      if (++nevents == ARRAY_SIZE(events)) {
+        if (kevent(loop->backend_fd, events, nevents, NULL, 0, NULL))
+          abort();
+        nevents = 0;
+      }
+    }
+
+    w->events = w->pevents;
+  }
+
+  pset = NULL;
+  if (loop->flags & UV_LOOP_BLOCK_SIGPROF) {
+    pset = &set;
+    sigemptyset(pset);
+    sigaddset(pset, SIGPROF);
+  }
+
+  assert(timeout >= -1);
+  base = loop->time;
+  count = 48; /* Benchmarks suggest this gives the best throughput. */
+
+  if (lfields->flags & UV_METRICS_IDLE_TIME) {
+    reset_timeout = 1;
+    user_timeout = timeout;
+    timeout = 0;
+  } else {
+    reset_timeout = 0;
+  }
+
+  for (;; nevents = 0) {
+    /* Only need to set the provider_entry_time if timeout != 0. The function
+     * will return early if the loop isn't configured with UV_METRICS_IDLE_TIME.
+     */
+    if (timeout != 0)
+      uv__metrics_set_provider_entry_time(loop);
+
+    if (timeout != -1) {
+      spec.tv_sec = timeout / 1000;
+      spec.tv_nsec = (timeout % 1000) * 1000000;
+    }
+
+    if (pset != NULL)
+      pthread_sigmask(SIG_BLOCK, pset, NULL);
+
+    /* Store the current timeout in a location that's globally accessible so
+     * other locations like uv__work_done() can determine whether the queue
+     * of events in the callback were waiting when poll was called.
+     */
+    lfields->current_timeout = timeout;
+
+    nfds = kevent(loop->backend_fd,
+                  events,
+                  nevents,
+                  events,
+                  ARRAY_SIZE(events),
+                  timeout == -1 ? NULL : &spec);
+
+    if (nfds == -1)
+      assert(errno == EINTR);
+    else if (nfds == 0)
+      /* Unlimited timeout should only return with events or signal. */
+      assert(timeout != -1);
+
+    if (pset != NULL)
+      pthread_sigmask(SIG_UNBLOCK, pset, NULL);
+
+    /* Update loop->time unconditionally. It's tempting to skip the update when
+     * timeout == 0 (i.e. non-blocking poll) but there is no guarantee that the
+     * operating system didn't reschedule our process while in the syscall.
+     */
+    uv__update_time(loop);
+
+    if (nfds == 0 || nfds == -1) {
+      /* If kqueue is empty or interrupted, we might still have children ready
+       * to reap immediately. */
+      if (loop->flags & UV_LOOP_REAP_CHILDREN) {
+        loop->flags &= ~UV_LOOP_REAP_CHILDREN;
+        uv__wait_children(loop);
+        assert((reset_timeout == 0 ? timeout : user_timeout) == 0);
+        return; /* Equivalent to fall-through behavior. */
+      }
+
+      if (reset_timeout != 0) {
+        timeout = user_timeout;
+        reset_timeout = 0;
+      } else if (nfds == 0) {
+        return;
+      }
+
+      /* Interrupted by a signal. Update timeout and poll again. */
+      goto update_timeout;
+    }
+
+    have_signals = 0;
+    nevents = 0;
+
+    assert(loop->watchers != NULL);
+    loop->watchers[loop->nwatchers] = (void*) events;
+    loop->watchers[loop->nwatchers + 1] = (void*) (uintptr_t) nfds;
+    for (i = 0; i < nfds; i++) {
+      ev = events + i;
+      fd = ev->ident;
+
+      /* Handle kevent NOTE_EXIT results */
+      if (ev->filter == EVFILT_PROC) {
+        uv__queue_foreach(q, &loop->process_handles) {
+          process = uv__queue_data(q, uv_process_t, queue);
+          if (process->pid == fd) {
+            process->flags |= UV_HANDLE_REAP;
+            loop->flags |= UV_LOOP_REAP_CHILDREN;
+            break;
+          }
+        }
+        nevents++;
+        continue;
+      }
+
+      /* Skip invalidated events, see uv__platform_invalidate_fd */
+      if (fd == -1)
+        continue;
+      w = loop->watchers[fd];
+
+      if (w == NULL) {
+        /* File descriptor that we've stopped watching, disarm it. */
+        uv__kqueue_delete(loop->backend_fd, ev);
+        continue;
+      }
+
+#if UV__KQUEUE_EVFILT_USER
+      if (ev->filter == EVFILT_USER) {
+        w = &loop->async_io_watcher;
+        assert(fd == w->fd);
+        uv__metrics_update_idle_time(loop);
+        w->cb(loop, w, w->events);
+        nevents++;
+        continue;
+      }
+#endif
+
+      if (ev->filter == EVFILT_VNODE) {
+        assert(w->events == POLLIN);
+        assert(w->pevents == POLLIN);
+        uv__metrics_update_idle_time(loop);
+        w->cb(loop, w, ev->fflags); /* XXX always uv__fs_event() */
+        nevents++;
+        continue;
+      }
+
+      revents = 0;
+
+      if (ev->filter == EVFILT_READ) {
+        if (w->pevents & POLLIN)
+          revents |= POLLIN;
+        else
+          uv__kqueue_delete(loop->backend_fd, ev);
+
+        if ((ev->flags & EV_EOF) && (w->pevents & UV__POLLRDHUP))
+          revents |= UV__POLLRDHUP;
+      }
+
+      if (ev->filter == EV_OOBAND) {
+        if (w->pevents & UV__POLLPRI)
+          revents |= UV__POLLPRI;
+        else
+          uv__kqueue_delete(loop->backend_fd, ev);
+      }
+
+      if (ev->filter == EVFILT_WRITE) {
+        if (w->pevents & POLLOUT)
+          revents |= POLLOUT;
+        else
+          uv__kqueue_delete(loop->backend_fd, ev);
+      }
+
+      if (ev->flags & EV_ERROR)
+        revents |= POLLERR;
+
+      if (revents == 0)
+        continue;
+
+      /* Run signal watchers last.  This also affects child process watchers
+       * because those are implemented in terms of signal watchers.
+       */
+      if (w == &loop->signal_io_watcher) {
+        have_signals = 1;
+      } else {
+        uv__metrics_update_idle_time(loop);
+        w->cb(loop, w, revents);
+      }
+
+      nevents++;
+    }
+
+    if (loop->flags & UV_LOOP_REAP_CHILDREN) {
+      loop->flags &= ~UV_LOOP_REAP_CHILDREN;
+      uv__wait_children(loop);
+    }
+
+    uv__metrics_inc_events(loop, nevents);
+    if (reset_timeout != 0) {
+      timeout = user_timeout;
+      reset_timeout = 0;
+      uv__metrics_inc_events_waiting(loop, nevents);
+    }
+
+    if (have_signals != 0) {
+      uv__metrics_update_idle_time(loop);
+      loop->signal_io_watcher.cb(loop, &loop->signal_io_watcher, POLLIN);
+    }
+
+    loop->watchers[loop->nwatchers] = NULL;
+    loop->watchers[loop->nwatchers + 1] = NULL;
+
+    if (have_signals != 0)
+      return;  /* Event loop should cycle now so don't poll again. */
+
+    if (nevents != 0) {
+      if (nfds == ARRAY_SIZE(events) && --count != 0) {
+        /* Poll for more events but don't block this time. */
+        timeout = 0;
+        continue;
+      }
+      return;
+    }
+
+update_timeout:
+    if (timeout == 0)
+      return;
+
+    if (timeout == -1)
+      continue;
+
+    assert(timeout > 0);
+
+    diff = loop->time - base;
+    if (diff >= (uint64_t) timeout)
+      return;
+
+    timeout -= diff;
+  }
+}
+
+
+void uv__platform_invalidate_fd(uv_loop_t* loop, int fd) {
+  struct kevent* events;
+  uintptr_t i;
+  uintptr_t nfds;
+
+  assert(loop->watchers != NULL);
+  assert(fd >= 0);
+
+  events = (struct kevent*) loop->watchers[loop->nwatchers];
+  nfds = (uintptr_t) loop->watchers[loop->nwatchers + 1];
+  if (events == NULL)
+    return;
+
+  /* Invalidate events with same file descriptor */
+  for (i = 0; i < nfds; i++)
+    if ((int) events[i].ident == fd && events[i].filter != EVFILT_PROC)
+      events[i].ident = -1;
+}
+
+
+static void uv__fs_event(uv_loop_t* loop, uv__io_t* w, unsigned int fflags) {
+  uv_fs_event_t* handle;
+  struct kevent ev;
+  int events;
+  const char* path;
+#if defined(F_GETPATH)
+  /* MAXPATHLEN == PATH_MAX but the former is what XNU calls it internally. */
+  char pathbuf[MAXPATHLEN];
+#endif
+
+  handle = container_of(w, uv_fs_event_t, event_watcher);
+
+  if (fflags & (NOTE_ATTRIB | NOTE_EXTEND))
+    events = UV_CHANGE;
+  else
+    events = UV_RENAME;
+
+  path = NULL;
+#if defined(F_GETPATH)
+  /* Also works when the file has been unlinked from the file system. Passing
+   * in the path when the file has been deleted is arguably a little strange
+   * but it's consistent with what the inotify backend does.
+   */
+  if (fcntl(handle->event_watcher.fd, F_GETPATH, pathbuf) == 0)
+    path = uv__basename_r(pathbuf);
+#elif defined(F_KINFO)
+  /* We try to get the file info reference from the file descriptor.
+   * the struct's kf_structsize must be initialised beforehand
+   * whether with the KINFO_FILE_SIZE constant or this way.
+   */
+  struct stat statbuf;
+  struct kinfo_file kf;
+
+  if (handle->event_watcher.fd != -1 &&
+     (!uv__fstat(handle->event_watcher.fd, &statbuf) && !(statbuf.st_mode & S_IFDIR))) {
+     /* we are purposely not using KINFO_FILE_SIZE here
+      * as it is not available on non intl archs
+      * and here it gives 1392 too on intel.
+      * anyway, the man page also mentions we can proceed
+      * this way.
+      */
+     kf.kf_structsize = sizeof(kf);
+     if (fcntl(handle->event_watcher.fd, F_KINFO, &kf) == 0)
+       path = uv__basename_r(kf.kf_path);
+  }
+#endif
+  handle->cb(handle, path, events, 0);
+
+  if (handle->event_watcher.fd == -1)
+    return;
+
+  /* Watcher operates in one-shot mode, re-arm it. */
+  fflags = NOTE_ATTRIB | NOTE_WRITE  | NOTE_RENAME
+         | NOTE_DELETE | NOTE_EXTEND | NOTE_REVOKE;
+
+  EV_SET(&ev, w->fd, EVFILT_VNODE, EV_ADD | EV_ONESHOT, fflags, 0, 0);
+
+  if (kevent(loop->backend_fd, &ev, 1, NULL, 0, NULL))
+    abort();
+}
+
+
+int uv_fs_event_init(uv_loop_t* loop, uv_fs_event_t* handle) {
+  uv__handle_init(loop, (uv_handle_t*)handle, UV_FS_EVENT);
+  return 0;
+}
+
+
+int uv_fs_event_start(uv_fs_event_t* handle,
+                      uv_fs_event_cb cb,
+                      const char* path,
+                      unsigned int flags) {
+  int fd;
+  int r;
+#if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 1070
+  struct stat statbuf;
+#endif
+
+  if (uv__is_active(handle))
+    return UV_EINVAL;
+
+  handle->cb = cb;
+  handle->path = uv__strdup(path);
+  if (handle->path == NULL)
+    return UV_ENOMEM;
+
+  /* TODO open asynchronously - but how do we report back errors? */
+  fd = open(handle->path, O_RDONLY);
+  if (fd == -1) {
+    uv__free(handle->path);
+    handle->path = NULL;
+    return UV__ERR(errno);
+  }
+
+#if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 1070
+  /* Nullify field to perform checks later */
+  handle->cf_cb = NULL;
+  handle->realpath = NULL;
+  handle->realpath_len = 0;
+  handle->cf_flags = flags;
+
+  if (uv__fstat(fd, &statbuf))
+    goto fallback;
+  /* FSEvents works only with directories */
+  if (!(statbuf.st_mode & S_IFDIR))
+    goto fallback;
+
+  if (0 == atomic_load_explicit(&uv__has_forked_with_cfrunloop,
+                                memory_order_relaxed)) {
+    /* The fallback fd is no longer needed */
+    uv__close_nocheckstdio(fd);
+    handle->event_watcher.fd = -1;
+    r = uv__fsevents_init(handle);
+    if (r == 0) {
+      uv__handle_start(handle);
+    } else {
+      uv__free(handle->path);
+      handle->path = NULL;
+    }
+    return r;
+  }
+fallback:
+#endif /* #if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 1070 */
+
+  r = uv__io_init_start(handle->loop,
+                        &handle->event_watcher,
+                        uv__fs_event,
+                        fd,
+                        POLLIN);
+
+  if (!r)
+    uv__handle_start(handle);
+
+  return r;
+}
+
+
+int uv_fs_event_stop(uv_fs_event_t* handle) {
+  int r;
+  r = 0;
+
+  if (!uv__is_active(handle))
+    return 0;
+
+  uv__handle_stop(handle);
+
+#if defined(__APPLE__) && MAC_OS_X_VERSION_MAX_ALLOWED >= 1070
+  if (0 == atomic_load_explicit(&uv__has_forked_with_cfrunloop,
+                                memory_order_relaxed))
+    if (handle->cf_cb != NULL)
+      r = uv__fsevents_close(handle);
+#endif
+
+  if (handle->event_watcher.fd != -1) {
+    uv__io_close(handle->loop, &handle->event_watcher);
+    uv__close(handle->event_watcher.fd);
+    handle->event_watcher.fd = -1;
+  }
+
+  uv__free(handle->path);
+  handle->path = NULL;
+
+  return r;
+}
+
+
+void uv__fs_event_close(uv_fs_event_t* handle) {
+  uv_fs_event_stop(handle);
+}