bool FSEventsWatcher::consumeNotify(
const std::shared_ptr<w_root_t>& root,
PendingCollection::LockedPtr& coll) {
struct timeval now;
bool recurse;
char flags_label[128];
std::deque<watchman_fsevent> items;
{
auto wlock = items_.wlock();
std::swap(items, *wlock);
}
gettimeofday(&now, nullptr);
for (auto& item : items) {
w_expand_flags(kflags, item.flags, flags_label, sizeof(flags_label));
w_log(
W_LOG_DBG,
"fsevents: got %s 0x%" PRIx32 " %s\n",
item.path.c_str(),
item.flags,
flags_label);
if (item.flags & kFSEventStreamEventFlagUserDropped) {
root->scheduleRecrawl("kFSEventStreamEventFlagUserDropped");
break;
}
if (item.flags & kFSEventStreamEventFlagKernelDropped) {
root->scheduleRecrawl("kFSEventStreamEventFlagKernelDropped");
break;
}
if (item.flags & kFSEventStreamEventFlagUnmount) {
w_log(
W_LOG_ERR,
"kFSEventStreamEventFlagUnmount %s, cancel watch\n",
item.path.c_str());
root->cancel();
break;
}
if (item.flags & kFSEventStreamEventFlagRootChanged) {
w_log(
W_LOG_ERR,
"kFSEventStreamEventFlagRootChanged %s, cancel watch\n",
item.path.c_str());
root->cancel();
break;
}
recurse = (item.flags & (kFSEventStreamEventFlagMustScanSubDirs |
kFSEventStreamEventFlagItemRenamed))
? true
: false;
coll->add(
item.path,
now,
W_PENDING_VIA_NOTIFY | (recurse ? W_PENDING_RECURSIVE : 0));
}
return !items.empty();
}
void InMemoryView::crawler(
const std::shared_ptr<w_root_t>& root,
SyncView::LockedPtr& view,
PendingCollection::LockedPtr& coll,
const w_string& dir_name,
struct timeval now,
bool recursive) {
struct watchman_file *file;
const watchman_dir_ent* dirent;
char path[WATCHMAN_NAME_MAX];
bool stat_all = false;
if (watcher_->flags & WATCHER_HAS_PER_FILE_NOTIFICATIONS) {
stat_all = watcher_->flags & WATCHER_COALESCED_RENAME;
} else {
// If the watcher doesn't give us per-file notifications for
// watched dirs, then we'll end up explicitly tracking them
// and will get updates for the files explicitly.
// We don't need to look at the files again when we crawl
stat_all = false;
}
auto dir = resolveDir(view, dir_name, true);
// Detect root directory replacement.
// The inode number check is handled more generally by the sister code
// in stat.cpp. We need to special case it for the root because we never
// generate a watchman_file node for the root and thus never call
// InMemoryView::statPath (we'll fault if we do!).
// Ideally the kernel would have given us a signal when we've been replaced
// but some filesystems (eg: BTRFS) do not emit appropriate inotify events
// for things like subvolume deletes. We've seen situations where the
// root has been replaced and we got no notifications at all and this has
// left the cookie sync mechanism broken forever.
if (dir_name == root->root_path) {
try {
auto st = getFileInformation(dir_name.c_str(), root->case_sensitive);
if (st.ino != view->rootInode) {
// If it still exists and the inode doesn't match, then we need
// to force recrawl to make sure we're in sync.
// We're lazily initializing the rootInode to 0 here, so we don't
// need to do this the first time through (we're already crawling
// everything in that case).
if (view->rootInode != 0) {
root->scheduleRecrawl(
"root was replaced and we didn't get notified by the kernel");
return;
}
recursive = true;
view->rootInode = st.ino;
}
} catch (const std::system_error& err) {
handle_open_errno(root, dir, now, "getFileInformation", err.code());
markDirDeleted(view, dir, now, true);
return;
}
}
memcpy(path, dir_name.data(), dir_name.size());
path[dir_name.size()] = 0;
w_log(W_LOG_DBG, "opendir(%s) recursive=%s\n",
path, recursive ? "true" : "false");
/* Start watching and open the dir for crawling.
* Whether we open the dir prior to watching or after is watcher specific,
* so the operations are rolled together in our abstraction */
std::unique_ptr<watchman_dir_handle> osdir;
try {
osdir = watcher_->startWatchDir(root, dir, path);
} catch (const std::system_error& err) {
handle_open_errno(root, dir, now, "opendir", err.code());
markDirDeleted(view, dir, now, true);
return;
}
if (dir->files.empty()) {
// Pre-size our hash(es) if we can, so that we can avoid collisions
// and re-hashing during initial crawl
uint32_t num_dirs = 0;
#ifndef _WIN32
struct stat st;
int dfd = osdir->getFd();
if (dfd != -1 && fstat(dfd, &st) == 0) {
num_dirs = (uint32_t)st.st_nlink;
}
#endif
// st.st_nlink is usually number of dirs + 2 (., ..).
// If it is less than 2 then it doesn't follow that convention.
// We just pass it through for the dir size hint and the hash
// table implementation will round that up to the next power of 2
apply_dir_size_hint(
dir,
num_dirs,
uint32_t(root->config.getInt("hint_num_files_per_dir", 64)));
}
/* flag for delete detection */
for (auto& it : dir->files) {
auto file = it.second.get();
if (file->exists) {
file->maybe_deleted = true;
}
}
try {
while ((dirent = osdir->readDir()) != nullptr) {
// Don't follow parent/self links
if (dirent->d_name[0] == '.' &&
(!strcmp(dirent->d_name, ".") || !strcmp(dirent->d_name, ".."))) {
continue;
}
// Queue it up for analysis if the file is newly existing
w_string name(dirent->d_name, W_STRING_BYTE);
file = dir->getChildFile(name);
if (file) {
file->maybe_deleted = false;
}
if (!file || !file->exists || stat_all || recursive) {
auto full_path = dir->getFullPathToChild(name);
w_log(
W_LOG_DBG,
"in crawler calling process_path on %s\n",
full_path.c_str());
processPath(
root,
view,
coll,
full_path,
now,
((recursive || !file || !file->exists) ? W_PENDING_RECURSIVE : 0),
dirent);
}
}
} catch (const std::system_error& exc) {
log(ERR,
"Error while reading dir ",
path,
": ",
exc.what(),
", re-adding to pending list to re-assess\n");
coll->add(path, now, 0);
}
osdir.reset();
// Anything still in maybe_deleted is actually deleted.
// Arrange to re-process it shortly
for (auto& it : dir->files) {
auto file = it.second.get();
if (file->exists &&
(file->maybe_deleted || (file->stat.isDir() && recursive))) {
coll->add(
dir,
file->getName().data(),
now,
recursive ? W_PENDING_RECURSIVE : 0);
}
}
}
bool KQueueWatcher::consumeNotify(
const std::shared_ptr<w_root_t>& root,
PendingCollection::LockedPtr& coll) {
int n;
int i;
struct timespec ts = { 0, 0 };
struct timeval now;
errno = 0;
n = kevent(
kq_fd.fd(),
nullptr,
0,
keventbuf,
sizeof(keventbuf) / sizeof(keventbuf[0]),
&ts);
w_log(
W_LOG_DBG,
"consume_kqueue: %s n=%d err=%s\n",
root->root_path.c_str(),
n,
strerror(errno));
if (root->inner.cancelled) {
return 0;
}
gettimeofday(&now, nullptr);
for (i = 0; n > 0 && i < n; i++) {
uint32_t fflags = keventbuf[i].fflags;
bool is_dir = IS_DIR_BIT_SET(keventbuf[i].udata);
char flags_label[128];
int fd = keventbuf[i].ident;
w_expand_flags(kflags, fflags, flags_label, sizeof(flags_label));
auto wlock = maps_.wlock();
auto it = wlock->fd_to_name.find(fd);
w_string path = it == wlock->fd_to_name.end() ? nullptr : it->second;
if (!path) {
// Was likely a buffered notification for something that we decided
// to stop watching
w_log(W_LOG_DBG,
" KQ notif for fd=%d; flags=0x%x %s no ref for it in fd_to_name\n",
fd, fflags, flags_label);
continue;
}
w_log(
W_LOG_DBG,
" KQ fd=%d path %s [0x%x %s]\n",
fd,
path.data(),
fflags,
flags_label);
if ((fflags & (NOTE_DELETE|NOTE_RENAME|NOTE_REVOKE))) {
struct kevent k;
if (w_string_equal(path, root->root_path)) {
w_log(
W_LOG_ERR,
"root dir %s has been (re)moved [code 0x%x], canceling watch\n",
root->root_path.c_str(),
fflags);
root->cancel();
return 0;
}
// Remove our watch bits
memset(&k, 0, sizeof(k));
EV_SET(&k, fd, EVFILT_VNODE, EV_DELETE, 0, 0, nullptr);
kevent(kq_fd.fd(), &k, 1, nullptr, 0, 0);
wlock->name_to_fd.erase(path);
wlock->fd_to_name.erase(fd);
}
coll->add(
path, now, is_dir ? 0 : (W_PENDING_RECURSIVE | W_PENDING_VIA_NOTIFY));
}
return n > 0;
}