win: compare entire filename in watch events

This commit causes Window file watching events to compare the
entire file path when filtering events. This fixes a bug where
incomplete path comparisons would cause invalid events to be
raised.

Refs: https://github.com/libuv/libuv/pull/682
PR-URL: https://github.com/libuv/libuv/pull/924
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>

src/win/fs-event.c

@@ -344,6 +344,22 @@ int uv_fs_event_stop(uv_fs_event_t* handle) {
 }
 
 
+static int file_info_cmp(WCHAR* str, WCHAR* file_name, int file_name_len) {
+  int str_len;
+
+  str_len = wcslen(str);
+
+  /*
+    Since we only care about equality, return early if the strings
+    aren't the same length
+  */
+  if (str_len != (file_name_len / sizeof(WCHAR)))
+    return -1;
+
+  return _wcsnicmp(str, file_name, str_len);
+}
+
+
 void uv_process_fs_event_req(uv_loop_t* loop, uv_req_t* req,
     uv_fs_event_t* handle) {
   FILE_NOTIFY_INFORMATION* file_info;
@@ -383,10 +399,12 @@ void uv_process_fs_event_req(uv_loop_t* loop, uv_req_t* req,
          * or if the filename filter matches.
          */
         if (handle->dirw ||
-          _wcsnicmp(handle->filew, file_info->FileName,
-            file_info->FileNameLength / sizeof(WCHAR)) == 0 ||
-          _wcsnicmp(handle->short_filew, file_info->FileName,
-            file_info->FileNameLength / sizeof(WCHAR)) == 0) {
+            file_info_cmp(handle->filew,
+                          file_info->FileName,
+                          file_info->FileNameLength) == 0 ||
+            file_info_cmp(handle->short_filew,
+                          file_info->FileName,
+                          file_info->FileNameLength) == 0) {
 
           if (handle->dirw) {
             /*

test/test-fs-event.c

@@ -53,6 +53,14 @@ static char fs_event_filename[PATH_MAX];
 static char fs_event_filename[1024];
 #endif  /* defined(PATH_MAX) */
 static int timer_cb_touch_called;
+static int timer_cb_exact_called;
+
+static void fs_event_fail(uv_fs_event_t* handle,
+                          const char* filename,
+                          int events,
+                          int status) {
+  ASSERT(0 && "should never be called");
+}
 
 static void create_dir(const char* name) {
   int r;
@@ -345,6 +353,21 @@ static void timer_cb_touch(uv_timer_t* timer) {
   timer_cb_touch_called++;
 }
 
+static void timer_cb_exact(uv_timer_t* handle) {
+  int r;
+
+  if (timer_cb_exact_called == 0) {
+    touch_file("watch_dir/file.js");
+  } else {
+    uv_close((uv_handle_t*)handle, NULL);
+    r = uv_fs_event_stop(&fs_event);
+    ASSERT(r == 0);
+    uv_close((uv_handle_t*) &fs_event, NULL);
+  }
+
+  ++timer_cb_exact_called;
+}
+
 static void timer_cb_watch_twice(uv_timer_t* handle) {
   uv_fs_event_t* handles = handle->data;
   uv_close((uv_handle_t*) (handles + 0), NULL);
@@ -467,6 +490,45 @@ TEST_IMPL(fs_event_watch_file) {
   return 0;
 }
 
+TEST_IMPL(fs_event_watch_file_exact_path) {
+  /*
+    This test watches a file named "file.jsx" and modifies a file named
+    "file.js". The test verifies that no events occur for file.jsx.
+  */
+  uv_loop_t* loop;
+  int r;
+
+  loop = uv_default_loop();
+
+  /* Setup */
+  remove("watch_dir/file.js");
+  remove("watch_dir/file.jsx");
+  remove("watch_dir/");
+  create_dir("watch_dir");
+  create_file("watch_dir/file.js");
+  create_file("watch_dir/file.jsx");
+
+  r = uv_fs_event_init(loop, &fs_event);
+  ASSERT(r == 0);
+  r = uv_fs_event_start(&fs_event, fs_event_fail, "watch_dir/file.jsx", 0);
+  ASSERT(r == 0);
+  r = uv_timer_init(loop, &timer);
+  ASSERT(r == 0);
+  r = uv_timer_start(&timer, timer_cb_exact, 100, 100);
+  ASSERT(r == 0);
+  r = uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT(r == 0);
+  ASSERT(timer_cb_exact_called == 2);
+
+  /* Cleanup */
+  remove("watch_dir/file.js");
+  remove("watch_dir/file.jsx");
+  remove("watch_dir/");
+
+  MAKE_VALGRIND_HAPPY();
+  return 0;
+}
+
 TEST_IMPL(fs_event_watch_file_twice) {
   const char path[] = "test/fixtures/empty_file";
   uv_fs_event_t watchers[2];
@@ -626,12 +688,6 @@ TEST_IMPL(fs_event_no_callback_on_close) {
 }
 
 
-static void fs_event_fail(uv_fs_event_t* handle, const char* filename,
-    int events, int status) {
-  ASSERT(0 && "should never be called");
-}
-
-
 static void timer_cb(uv_timer_t* handle) {
   int r;
 

test/test-list.h

@@ -275,6 +275,7 @@ 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_exact_path)
 TEST_DECLARE   (fs_event_watch_file_twice)
 TEST_DECLARE   (fs_event_watch_file_current_dir)
 #ifdef _WIN32
@@ -724,6 +725,7 @@ TASK_LIST_START
   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_exact_path)
   TEST_ENTRY  (fs_event_watch_file_twice)
   TEST_ENTRY  (fs_event_watch_file_current_dir)
 #ifdef _WIN32