win: add support for recursive file watching

Original patch by @ghostoy, modified by @bpasero and yours truly.

Refs: joyent/libuv#1473
Refs: libuv#198
PR-URL: libuv#421
Reviewed-By: Bert Belder <bertbelder@gmail.com>

Author: saghul

docs/src/fs_event.rst

@@ -88,7 +88,7 @@ API
     `path` for changes. `flags` can be an ORed mask of :c:type:`uv_fs_event_flags`.
 
     .. note:: Currently the only supported flag is ``UV_FS_EVENT_RECURSIVE`` and
-              only on OSX.
+              only on OSX and Windows.
 
 .. c:function:: int uv_fs_event_stop(uv_fs_event_t* handle)
 

src/win/fs-event.c

@@ -43,7 +43,7 @@ static void uv_fs_event_queue_readdirchanges(uv_loop_t* loop,
   if (!ReadDirectoryChangesW(handle->dir_handle,
                              handle->buffer,
                              uv_directory_watcher_buffer_size,
-                             FALSE,
+                             (handle->flags & UV_FS_EVENT_RECURSIVE) ? TRUE : FALSE,
                              FILE_NOTIFY_CHANGE_FILE_NAME      |
                                FILE_NOTIFY_CHANGE_DIR_NAME     |
                                FILE_NOTIFY_CHANGE_ATTRIBUTES   |
@@ -63,6 +63,20 @@ static void uv_fs_event_queue_readdirchanges(uv_loop_t* loop,
   handle->req_pending = 1;
 }
 
+static int uv_relative_path(const WCHAR* filename,
+                            const WCHAR* dir,
+	                    WCHAR** relpath) {
+  int dirlen = wcslen(dir);
+  int filelen = wcslen(filename);
+  if (dir[dirlen - 1] == '\\')
+    dirlen--;
+  *relpath = uv__malloc((MAX_PATH + 1) * sizeof(WCHAR));
+  if (!*relpath)
+    uv_fatal_error(ERROR_OUTOFMEMORY, "uv__malloc");
+  wcsncpy(*relpath, filename + dirlen + 1, filelen - dirlen - 1);
+  (*relpath)[filelen - dirlen - 1] = L'\0';
+  return 0;
+}
 
 static int uv_split_path(const WCHAR* filename, WCHAR** dir,
     WCHAR** file) {
@@ -237,7 +251,7 @@ int uv_fs_event_start(uv_fs_event_t* handle,
   if (!ReadDirectoryChangesW(handle->dir_handle,
                              handle->buffer,
                              uv_directory_watcher_buffer_size,
-                             FALSE,
+                             (flags & UV_FS_EVENT_RECURSIVE) ? TRUE : FALSE,
                              FILE_NOTIFY_CHANGE_FILE_NAME      |
                                FILE_NOTIFY_CHANGE_DIR_NAME     |
                                FILE_NOTIFY_CHANGE_ATTRIBUTES   |
@@ -410,7 +424,9 @@ void uv_process_fs_event_req(uv_loop_t* loop, uv_req_t* req,
 
               if (long_filenamew) {
                 /* Get the file name out of the long path. */
-                result = uv_split_path(long_filenamew, NULL, &filenamew);
+                result = uv_relative_path(long_filenamew,
+                                          handle->dirw,
+                                          &filenamew);
                 uv__free(long_filenamew);
 
                 if (result == 0) {

src/win/internal.h

@@ -64,7 +64,7 @@ extern UV_THREAD_LOCAL int uv__crt_assert_enabled;
 
 /* Used by all handles. */
 #define UV_HANDLE_CLOSED                        0x00000002
-#define UV_HANDLE_ENDGAME_QUEUED                0x00000004
+#define UV_HANDLE_ENDGAME_QUEUED                0x00000008
 
 /* uv-common.h: #define UV__HANDLE_CLOSING      0x00000001 */
 /* uv-common.h: #define UV__HANDLE_ACTIVE       0x00000040 */

test/test-fs-event.c

@@ -37,6 +37,7 @@
 
 static uv_fs_event_t fs_event;
 static const char file_prefix[] = "fsevent-";
+static const char file_prefix_in_subdir[] = "subdir";
 static uv_timer_t timer;
 static int timer_cb_called;
 static int close_cb_called;
@@ -51,6 +52,7 @@ static char fs_event_filename[1024];
 static int timer_cb_touch_called;
 
 static void fs_event_unlink_files(uv_timer_t* handle);
+static void fs_event_unlink_files_in_subdir(uv_timer_t* handle);
 
 static void create_dir(uv_loop_t* loop, const char* name) {
   int r;
@@ -138,6 +140,25 @@ static void fs_event_cb_dir_multi_file(uv_fs_event_t* handle,
   }
 }
 
+static void fs_event_cb_dir_multi_file_in_subdir(uv_fs_event_t* handle,
+                                       const char* filename,
+                                       int events,
+                                       int status) {
+  fs_event_cb_called++;
+  ASSERT(handle == &fs_event);
+  ASSERT(status == 0);
+  ASSERT(events == UV_RENAME || events == UV_CHANGE);
+  ASSERT(filename == NULL ||
+         strncmp(filename, file_prefix_in_subdir, sizeof(file_prefix_in_subdir) - 1) == 0);
+
+  /* Stop watching dir when received events about all files:
+   * both create and close events */
+  if (fs_event_cb_called == 2 * fs_event_file_count) {
+    ASSERT(0 == uv_fs_event_stop(handle));
+    uv_close((uv_handle_t*) handle, close_cb);
+  }
+}
+
 static const char* fs_event_get_filename(int i) {
   snprintf(fs_event_filename,
            sizeof(fs_event_filename),
@@ -147,6 +168,15 @@ static const char* fs_event_get_filename(int i) {
   return fs_event_filename;
 }
 
+static const char* fs_event_get_filename_in_subdir(int i) {
+  snprintf(fs_event_filename,
+           sizeof(fs_event_filename),
+           "watch_dir/subdir/%s%d",
+           file_prefix,
+           i);
+  return fs_event_filename;
+}
+
 static void fs_event_create_files(uv_timer_t* handle) {
   int i;
 
@@ -164,6 +194,41 @@ static void fs_event_create_files(uv_timer_t* handle) {
   ASSERT(0 == uv_timer_start(&timer, fs_event_unlink_files, 50, 0));
 }
 
+static void fs_event_create_files_in_subdir(uv_timer_t* handle) {
+  int i;
+
+  /* Already created all files */
+  if (fs_event_created == fs_event_file_count) {
+    uv_close((uv_handle_t*) &timer, close_cb);
+    return;
+  }
+
+  /* Create all files */
+  for (i = 0; i < 16; i++, fs_event_created++)
+    create_file(handle->loop, fs_event_get_filename_in_subdir(i));
+
+  /* And unlink them */
+  ASSERT(0 == uv_timer_start(&timer, fs_event_unlink_files_in_subdir, 50, 0));
+}
+
+void fs_event_unlink_files_in_subdir(uv_timer_t* handle) {
+  int r;
+  int i;
+
+  /* NOTE: handle might be NULL if invoked not as timer callback */
+
+  /* Unlink all files */
+  for (i = 0; i < 16; i++) {
+    r = remove(fs_event_get_filename_in_subdir(i));
+    if (handle != NULL)
+      ASSERT(r == 0);
+  }
+
+  /* And create them again */
+  if (handle != NULL)
+    ASSERT(0 == uv_timer_start(&timer, fs_event_create_files_in_subdir, 50, 0));
+}
+
 void fs_event_unlink_files(uv_timer_t* handle) {
   int r;
   int i;
@@ -282,6 +347,51 @@ TEST_IMPL(fs_event_watch_dir) {
   return 0;
 }
 
+TEST_IMPL(fs_event_watch_dir_recursive) {
+#if defined(__APPLE__) || defined(_WIN32)
+  uv_loop_t* loop;
+  int r;
+
+  /* Setup */
+  loop = uv_default_loop();
+  fs_event_unlink_files(NULL);
+  remove("watch_dir/file2");
+  remove("watch_dir/file1");
+  remove("watch_dir/subdir");
+  remove("watch_dir/");
+  create_dir(loop, "watch_dir");
+  create_dir(loop, "watch_dir/subdir");
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT(r == 0);
+  r = uv_fs_event_start(&fs_event, fs_event_cb_dir_multi_file_in_subdir, "watch_dir", UV_FS_EVENT_RECURSIVE);
+  ASSERT(r == 0);
+  r = uv_timer_init(loop, &timer);
+  ASSERT(r == 0);
+  r = uv_timer_start(&timer, fs_event_create_files_in_subdir, 100, 0);
+  ASSERT(r == 0);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT(fs_event_cb_called == 2 * fs_event_file_count);
+  ASSERT(fs_event_created == fs_event_file_count);
+  ASSERT(close_cb_called == 2);
+
+  /* Cleanup */
+  fs_event_unlink_files_in_subdir(NULL);
+  remove("watch_dir/file2");
+  remove("watch_dir/file1");
+  remove("watch_dir/subdir");
+  remove("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY();
+  return 0;
+#else
+  RETURN_SKIP("Recursive directory watching not supported on this platform.");
+#endif
+}
+
+
 TEST_IMPL(fs_event_watch_file) {
   uv_loop_t* loop = uv_default_loop();
   int r;

test/test-list.h

@@ -258,6 +258,7 @@ TEST_DECLARE   (fs_file_open_append)
 TEST_DECLARE   (fs_stat_missing_path)
 TEST_DECLARE   (fs_read_file_eof)
 TEST_DECLARE   (fs_event_watch_dir)
+TEST_DECLARE   (fs_event_watch_dir_recursive)
 TEST_DECLARE   (fs_event_watch_file)
 TEST_DECLARE   (fs_event_watch_file_twice)
 TEST_DECLARE   (fs_event_watch_file_current_dir)
@@ -664,6 +665,7 @@ TASK_LIST_START
   TEST_ENTRY  (fs_read_file_eof)
   TEST_ENTRY  (fs_file_open_append)
   TEST_ENTRY  (fs_event_watch_dir)
+  TEST_ENTRY  (fs_event_watch_dir_recursive)
   TEST_ENTRY  (fs_event_watch_file)
   TEST_ENTRY  (fs_event_watch_file_twice)
   TEST_ENTRY  (fs_event_watch_file_current_dir)