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-rw-r--r--Utilities/cmlibuv/src/unix/linux-inotify.c285
1 files changed, 285 insertions, 0 deletions
diff --git a/Utilities/cmlibuv/src/unix/linux-inotify.c b/Utilities/cmlibuv/src/unix/linux-inotify.c
new file mode 100644
index 0000000..4708c05
--- /dev/null
+++ b/Utilities/cmlibuv/src/unix/linux-inotify.c
@@ -0,0 +1,285 @@
+/* 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 "tree.h"
+#include "internal.h"
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <errno.h>
+
+#include <sys/types.h>
+#include <unistd.h>
+
+struct watcher_list {
+ RB_ENTRY(watcher_list) entry;
+ QUEUE watchers;
+ int iterating;
+ char* path;
+ int wd;
+};
+
+struct watcher_root {
+ struct watcher_list* rbh_root;
+};
+#define CAST(p) ((struct watcher_root*)(p))
+
+
+static int compare_watchers(const struct watcher_list* a,
+ const struct watcher_list* b) {
+ if (a->wd < b->wd) return -1;
+ if (a->wd > b->wd) return 1;
+ return 0;
+}
+
+
+RB_GENERATE_STATIC(watcher_root, watcher_list, entry, compare_watchers)
+
+
+static void uv__inotify_read(uv_loop_t* loop,
+ uv__io_t* w,
+ unsigned int revents);
+
+
+static int new_inotify_fd(void) {
+ int err;
+ int fd;
+
+ fd = uv__inotify_init1(UV__IN_NONBLOCK | UV__IN_CLOEXEC);
+ if (fd != -1)
+ return fd;
+
+ if (errno != ENOSYS)
+ return -errno;
+
+ fd = uv__inotify_init();
+ if (fd == -1)
+ return -errno;
+
+ err = uv__cloexec(fd, 1);
+ if (err == 0)
+ err = uv__nonblock(fd, 1);
+
+ if (err) {
+ uv__close(fd);
+ return err;
+ }
+
+ return fd;
+}
+
+
+static int init_inotify(uv_loop_t* loop) {
+ int err;
+
+ if (loop->inotify_fd != -1)
+ return 0;
+
+ err = new_inotify_fd();
+ if (err < 0)
+ return err;
+
+ loop->inotify_fd = err;
+ uv__io_init(&loop->inotify_read_watcher, uv__inotify_read, loop->inotify_fd);
+ uv__io_start(loop, &loop->inotify_read_watcher, POLLIN);
+
+ return 0;
+}
+
+
+static struct watcher_list* find_watcher(uv_loop_t* loop, int wd) {
+ struct watcher_list w;
+ w.wd = wd;
+ return RB_FIND(watcher_root, CAST(&loop->inotify_watchers), &w);
+}
+
+static void maybe_free_watcher_list(struct watcher_list* w, uv_loop_t* loop) {
+ /* if the watcher_list->watchers is being iterated over, we can't free it. */
+ if ((!w->iterating) && QUEUE_EMPTY(&w->watchers)) {
+ /* No watchers left for this path. Clean up. */
+ RB_REMOVE(watcher_root, CAST(&loop->inotify_watchers), w);
+ uv__inotify_rm_watch(loop->inotify_fd, w->wd);
+ uv__free(w);
+ }
+}
+
+static void uv__inotify_read(uv_loop_t* loop,
+ uv__io_t* dummy,
+ unsigned int events) {
+ const struct uv__inotify_event* e;
+ struct watcher_list* w;
+ uv_fs_event_t* h;
+ QUEUE queue;
+ QUEUE* q;
+ const char* path;
+ ssize_t size;
+ const char *p;
+ /* needs to be large enough for sizeof(inotify_event) + strlen(path) */
+ char buf[4096];
+
+ while (1) {
+ do
+ size = read(loop->inotify_fd, buf, sizeof(buf));
+ while (size == -1 && errno == EINTR);
+
+ if (size == -1) {
+ assert(errno == EAGAIN || errno == EWOULDBLOCK);
+ break;
+ }
+
+ assert(size > 0); /* pre-2.6.21 thing, size=0 == read buffer too small */
+
+ /* Now we have one or more inotify_event structs. */
+ for (p = buf; p < buf + size; p += sizeof(*e) + e->len) {
+ e = (const struct uv__inotify_event*)p;
+
+ events = 0;
+ if (e->mask & (UV__IN_ATTRIB|UV__IN_MODIFY))
+ events |= UV_CHANGE;
+ if (e->mask & ~(UV__IN_ATTRIB|UV__IN_MODIFY))
+ events |= UV_RENAME;
+
+ w = find_watcher(loop, e->wd);
+ if (w == NULL)
+ continue; /* Stale event, no watchers left. */
+
+ /* inotify does not return the filename when monitoring a single file
+ * for modifications. Repurpose the filename for API compatibility.
+ * I'm not convinced this is a good thing, maybe it should go.
+ */
+ path = e->len ? (const char*) (e + 1) : uv__basename_r(w->path);
+
+ /* We're about to iterate over the queue and call user's callbacks.
+ * What can go wrong?
+ * A callback could call uv_fs_event_stop()
+ * and the queue can change under our feet.
+ * So, we use QUEUE_MOVE() trick to safely iterate over the queue.
+ * And we don't free the watcher_list until we're done iterating.
+ *
+ * First,
+ * tell uv_fs_event_stop() (that could be called from a user's callback)
+ * not to free watcher_list.
+ */
+ w->iterating = 1;
+ QUEUE_MOVE(&w->watchers, &queue);
+ while (!QUEUE_EMPTY(&queue)) {
+ q = QUEUE_HEAD(&queue);
+ h = QUEUE_DATA(q, uv_fs_event_t, watchers);
+
+ QUEUE_REMOVE(q);
+ QUEUE_INSERT_TAIL(&w->watchers, q);
+
+ h->cb(h, path, events, 0);
+ }
+ /* done iterating, time to (maybe) free empty watcher_list */
+ w->iterating = 0;
+ maybe_free_watcher_list(w, loop);
+ }
+ }
+}
+
+
+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) {
+ struct watcher_list* w;
+ int events;
+ int err;
+ int wd;
+
+ if (uv__is_active(handle))
+ return -EINVAL;
+
+ err = init_inotify(handle->loop);
+ if (err)
+ return err;
+
+ events = UV__IN_ATTRIB
+ | UV__IN_CREATE
+ | UV__IN_MODIFY
+ | UV__IN_DELETE
+ | UV__IN_DELETE_SELF
+ | UV__IN_MOVE_SELF
+ | UV__IN_MOVED_FROM
+ | UV__IN_MOVED_TO;
+
+ wd = uv__inotify_add_watch(handle->loop->inotify_fd, path, events);
+ if (wd == -1)
+ return -errno;
+
+ w = find_watcher(handle->loop, wd);
+ if (w)
+ goto no_insert;
+
+ w = uv__malloc(sizeof(*w) + strlen(path) + 1);
+ if (w == NULL)
+ return -ENOMEM;
+
+ w->wd = wd;
+ w->path = strcpy((char*)(w + 1), path);
+ QUEUE_INIT(&w->watchers);
+ w->iterating = 0;
+ RB_INSERT(watcher_root, CAST(&handle->loop->inotify_watchers), w);
+
+no_insert:
+ uv__handle_start(handle);
+ QUEUE_INSERT_TAIL(&w->watchers, &handle->watchers);
+ handle->path = w->path;
+ handle->cb = cb;
+ handle->wd = wd;
+
+ return 0;
+}
+
+
+int uv_fs_event_stop(uv_fs_event_t* handle) {
+ struct watcher_list* w;
+
+ if (!uv__is_active(handle))
+ return 0;
+
+ w = find_watcher(handle->loop, handle->wd);
+ assert(w != NULL);
+
+ handle->wd = -1;
+ handle->path = NULL;
+ uv__handle_stop(handle);
+ QUEUE_REMOVE(&handle->watchers);
+
+ maybe_free_watcher_list(w, handle->loop);
+
+ return 0;
+}
+
+
+void uv__fs_event_close(uv_fs_event_t* handle) {
+ uv_fs_event_stop(handle);
+}