darwin: look up file path with F_GETPATH

Look up the file path with fcntl(F_GETPATH) and pass it to
the uv_fs_event_cb callback.

src/unix/internal.h

@@ -26,6 +26,7 @@
 
 #include <assert.h>
 #include <stdlib.h> /* abort */
+#include <string.h> /* strrchr */
 
 #if defined(__STRICT_ANSI__)
 # define inline __inline
@@ -256,6 +257,18 @@ static void uv__update_time(uv_loop_t* loop) {
   loop->time = uv__hrtime() / 1000000;
 }
 
+__attribute__((unused))
+static char* uv__basename_r(const char* path) {
+  char* s;
+
+  s = strrchr(path, '/');
+  if (s == NULL)
+    return (char*) path;
+
+  return s + 1;
+}
+
+
 #ifdef HAVE_DTRACE
 #include "uv-dtrace.h"
 #else

src/unix/kqueue.c

@@ -259,6 +259,11 @@ 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);
 
@@ -267,7 +272,16 @@ static void uv__fs_event(uv_loop_t* loop, uv__io_t* w, unsigned int fflags) {
   else
     events = UV_RENAME;
 
-  handle->cb(handle, NULL, events, 0);
+  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);
+#endif
+  handle->cb(handle, path, events, 0);
 
   if (handle->event_watcher.fd == -1)
     return;

src/unix/linux-inotify.c

@@ -45,13 +45,6 @@ struct watcher_root {
 #define CAST(p) ((struct watcher_root*)(p))
 
 
-/* Don't look aghast, this is exactly how glibc's basename() works. */
-static char* basename_r(const char* path) {
-  char* s = strrchr(path, '/');
-  return s ? (s + 1) : (char*)path;
-}
-
-
 static int compare_watchers(const struct watcher_list* a,
                             const struct watcher_list* b) {
   if (a->wd < b->wd) return -1;
@@ -156,7 +149,7 @@ static void uv__inotify_read(uv_loop_t* loop,
        * 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) : basename_r(w->path);
+      path = e->len ? (const char*) (e + 1) : uv__basename_r(w->path);
 
       QUEUE_FOREACH(q, &w->watchers) {
         h = QUEUE_DATA(q, uv_fs_event_t, watchers);