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-rw-r--r--ChangeLog24
-rw-r--r--NEWS12
-rw-r--r--nscd/cache.c28
-rw-r--r--nscd/connections.c358
-rw-r--r--nscd/nscd.h60
-rw-r--r--nss/nss_db/db-init.c28
-rw-r--r--nss/nss_files/files-init.c46
7 files changed, 398 insertions, 158 deletions
diff --git a/ChangeLog b/ChangeLog
index d6526e9862..f5545b1c1d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,27 @@
+2015-03-13  Carlos O'Donell  <carlos@redhat.com>
+
+	[BZ #14906]
+	* nscd/cache.c (prune_cache): Use TRACED_FILE. Compare and update
+	traced file mtime. Use consistent log message.
+	* nscd/connections.c [HAVE_INOTIFY] (install_watches): New function.
+	(register_traced_file): Call install_watches. Always set mtime.
+	(invalidate_cache): Iterate over all trace files. Call install_watches.
+	(inotify_check_files): Don't inline. Handle watching parent
+	directories and configuration file movement in and out.
+	(handle_inotify_events): New function.
+	(main_loop_poll): Call handle_inotify_events.
+	(main_loop_epoll): Likewise.
+	* nscd/nscd.h: Define TRACED_FILE, TRACED_DIR, and PATH_MAX.
+	(struct traced_file): Use array of inotify fds. Add parent directory,
+	and basename.
+	(struct database_dyn): Remove unused file_mtime.
+	(init_traced_file): New inline function.
+	(define_traced_file): New macro.
+	* nss/nss_db/db-init.c: Use define_traced_file.
+	(_nss_db_init): Use init_traced_file.
+	* nss/nss_files/files-init.c: Use define_traced_file.
+	(_nss_files_init): Use init_traced_file.
+
 2015-03-12  Joseph Myers  <joseph@codesourcery.com>
 
 	* soft-fp/soft-fp.h (_FP_STATIC_ASSERT): New macro.
diff --git a/NEWS b/NEWS
index 88bfc44a33..4e0024bd1a 100644
--- a/NEWS
+++ b/NEWS
@@ -9,12 +9,12 @@ Version 2.22
 
 * The following bugs are resolved with this release:
 
-  4719, 13064, 14094, 14841, 15319, 15467, 15790, 15969, 16351, 16512,
-  16560, 16783, 17269, 17523, 17569, 17588, 17631, 17711, 17776, 17779,
-  17792, 17836, 17912, 17916, 17932, 17944, 17949, 17964, 17965, 17967,
-  17969, 17978, 17987, 17991, 17996, 17998, 17999, 18019, 18020, 18029,
-  18030, 18032, 18036, 18038, 18039, 18042, 18043, 18046, 18047, 18068,
-  18080, 18093, 18104, 18110, 18111.
+  4719, 13064, 14094, 14841, 14906, 15319, 15467, 15790, 15969, 16351,
+  16512, 16560, 16783, 17269, 17523, 17569, 17588, 17631, 17711, 17776,
+  17779, 17792, 17836, 17912, 17916, 17932, 17944, 17949, 17964, 17965,
+  17967, 17969, 17978, 17987, 17991, 17996, 17998, 17999, 18019, 18020,
+  18029, 18030, 18032, 18036, 18038, 18039, 18042, 18043, 18046, 18047,
+  18068, 18080, 18093, 18104, 18110, 18111.
 
 * Character encoding and ctype tables were updated to Unicode 7.0.0, using
   new generator scripts contributed by Pravin Satpute and Mike FABIAN (Red
diff --git a/nscd/cache.c b/nscd/cache.c
index ea9f72311b..f0200c303c 100644
--- a/nscd/cache.c
+++ b/nscd/cache.c
@@ -272,28 +272,38 @@ prune_cache (struct database_dyn *table, time_t now, int fd)
       while (runp != NULL)
 	{
 #ifdef HAVE_INOTIFY
-	  if (runp->inotify_descr == -1)
+	  if (runp->inotify_descr[TRACED_FILE] == -1)
 #endif
 	    {
 	      struct stat64 st;
 
 	      if (stat64 (runp->fname, &st) < 0)
 		{
+		  /* Print a diagnostic that the traced file was missing.
+		     We must not disable tracing since the file might return
+		     shortly and we want to reload it at the next pruning.
+		     Disabling tracing here would go against the configuration
+		     as specified by the user via check-files.  */
 		  char buf[128];
-		  /* We cannot stat() the file, disable file checking if the
-		     file does not exist.  */
-		  dbg_log (_("cannot stat() file `%s': %s"),
+		  dbg_log (_("checking for monitored file `%s': %s"),
 			   runp->fname, strerror_r (errno, buf, sizeof (buf)));
-		  if (errno == ENOENT)
-		    table->check_file = 0;
 		}
 	      else
 		{
-		  if (st.st_mtime != table->file_mtime)
+		  /* This must be `!=` to catch cases where users turn the
+		     clocks back and we still want to detect any time difference
+		     in mtime.  */
+		  if (st.st_mtime != runp->mtime)
 		    {
-		      /* The file changed.  Invalidate all entries.  */
+		      dbg_log (_("monitored file `%s` changed (mtime)"),
+			       runp->fname);
+		      /* The file changed. Invalidate all entries.  */
 		      now = LONG_MAX;
-		      table->file_mtime = st.st_mtime;
+		      runp->mtime = st.st_mtime;
+#ifdef HAVE_INOTIFY
+		      /* Attempt to install a watch on the file.  */
+		      install_watches (runp);
+#endif
 		    }
 		}
 	    }
diff --git a/nscd/connections.c b/nscd/connections.c
index 985eab6a30..cba5e6ad9d 100644
--- a/nscd/connections.c
+++ b/nscd/connections.c
@@ -957,6 +957,44 @@ cannot change socket to nonblocking mode: %s"),
     finish_drop_privileges ();
 }
 
+#ifdef HAVE_INOTIFY
+#define TRACED_FILE_MASK (IN_DELETE_SELF | IN_CLOSE_WRITE | IN_MOVE_SELF)
+#define TRACED_DIR_MASK (IN_DELETE_SELF | IN_CREATE | IN_MOVED_TO | IN_MOVE_SELF)
+void
+install_watches (struct traced_file *finfo)
+{
+  /* Use inotify support if we have it.  */
+  if (finfo->inotify_descr[TRACED_FILE] < 0)
+    finfo->inotify_descr[TRACED_FILE] = inotify_add_watch (inotify_fd,
+							   finfo->fname,
+							   TRACED_FILE_MASK);
+  if (finfo->inotify_descr[TRACED_FILE] < 0)
+    {
+      dbg_log (_("disabled inotify-based monitoring for file `%s': %s"),
+		 finfo->fname, strerror (errno));
+      return;
+    }
+  dbg_log (_("monitoring file `%s` (%d)"),
+	   finfo->fname, finfo->inotify_descr[TRACED_FILE]);
+  /* Additionally listen for events in the file's parent directory.
+     We do this because the file to be watched might be
+     deleted and then added back again.  When it is added back again
+     we must re-add the watch.  We must also cover IN_MOVED_TO to
+     detect a file being moved into the directory.  */
+  if (finfo->inotify_descr[TRACED_DIR] < 0)
+    finfo->inotify_descr[TRACED_DIR] = inotify_add_watch (inotify_fd,
+							  finfo->dname,
+							  TRACED_DIR_MASK);
+  if (finfo->inotify_descr[TRACED_DIR] < 0)
+    {
+      dbg_log (_("disabled inotify-based monitoring for directory `%s': %s"),
+		 finfo->fname, strerror (errno));
+      return;
+    }
+  dbg_log (_("monitoring directory `%s` (%d)"),
+	   finfo->dname, finfo->inotify_descr[TRACED_DIR]);
+}
+#endif
 
 /* Register the file in FINFO as a traced file for the database DBS[DBIX].
 
@@ -981,30 +1019,22 @@ register_traced_file (size_t dbidx, struct traced_file *finfo)
     return;
 
   if (__glibc_unlikely (debug_level > 0))
-    dbg_log (_("register trace file %s for database %s"),
+    dbg_log (_("monitoring file %s for database %s"),
 	     finfo->fname, dbnames[dbidx]);
 
 #ifdef HAVE_INOTIFY
-  if (inotify_fd < 0
-      || (finfo->inotify_descr = inotify_add_watch (inotify_fd, finfo->fname,
-						    IN_DELETE_SELF
-						    | IN_MODIFY)) < 0)
+  install_watches (finfo);
 #endif
+  struct stat64 st;
+  if (stat64 (finfo->fname, &st) < 0)
     {
-      /* We need the modification date of the file.  */
-      struct stat64 st;
-
-      if (stat64 (finfo->fname, &st) < 0)
-	{
-	  /* We cannot stat() the file, disable file checking.  */
-	  dbg_log (_("cannot stat() file `%s': %s"),
-		   finfo->fname, strerror (errno));
-	  return;
-	}
-
-      finfo->inotify_descr = -1;
-      finfo->mtime = st.st_mtime;
+      /* We cannot stat() the file. Set mtime to zero and try again later.  */
+      dbg_log (_("stat failed for file `%s'; will try again later: %s"),
+	       finfo->fname, strerror (errno));
+      finfo->mtime = 0;
     }
+  else
+    finfo->mtime = st.st_mtime;
 
   /* Queue up the file name.  */
   finfo->next = dbs[dbidx].traced_files;
@@ -1029,20 +1059,27 @@ invalidate_cache (char *key, int fd)
   for (number = pwddb; number < lastdb; ++number)
     if (strcmp (key, dbnames[number]) == 0)
       {
-	if (number == hstdb)
+	struct traced_file *runp = dbs[number].traced_files;
+	while (runp != NULL)
 	  {
-	    struct traced_file *runp = dbs[hstdb].traced_files;
-	    while (runp != NULL)
-	      if (runp->call_res_init)
-		{
-		  res_init ();
-		  break;
-		}
-	      else
-		runp = runp->next;
+	    /* Make sure we reload from file when checking mtime.  */
+	    runp->mtime = 0;
+#ifdef HAVE_INOTIFY
+	    /* During an invalidation we try to reload the traced
+	       file watches.  This allows the user to re-sync if
+	       inotify events were lost.  Similar to what we do during
+	       pruning.  */
+	    install_watches (runp);
+#endif
+	    if (runp->call_res_init)
+	      {
+		res_init ();
+		break;
+	      }
+	    runp = runp->next;
 	  }
 	break;
-    }
+      }
 
   if (number == lastdb)
     {
@@ -1880,11 +1917,28 @@ union __inev
   char buf[sizeof (struct inotify_event) + PATH_MAX];
 };
 
+/* Returns 0 if the file is there otherwise -1.  */
+int
+check_file (struct traced_file *finfo)
+{
+  struct stat64 st;
+  /* We could check mtime and if different re-add
+     the watches, and invalidate the database, but we
+     don't because we are called from inotify_check_files
+     which should be doing that work.  If sufficient inotify
+     events were lost then the next pruning or invalidation
+     will do the stat and mtime check.  We don't do it here to
+     keep the logic simple.  */
+  if (stat64 (finfo->fname, &st) < 0)
+    return -1;
+  return 0;
+}
+
 /* Process the inotify event in INEV. If the event matches any of the files
    registered with a database then mark that database as requiring its cache
    to be cleared. We indicate the cache needs clearing by setting
    TO_CLEAR[DBCNT] to true for the matching database.  */
-static inline void
+static void
 inotify_check_files (bool *to_clear, union __inev *inev)
 {
   /* Check which of the files changed.  */
@@ -1894,16 +1948,124 @@ inotify_check_files (bool *to_clear, union __inev *inev)
 
       while (finfo != NULL)
 	{
-	  /* Inotify event watch descriptor matches.  */
-	  if (finfo->inotify_descr == inev->i.wd)
+	  /* The configuration file was moved or deleted.
+	     We stop watching it at that point, and reinitialize.  */
+	  if (finfo->inotify_descr[TRACED_FILE] == inev->i.wd
+	      && ((inev->i.mask & IN_MOVE_SELF)
+		  || (inev->i.mask & IN_DELETE_SELF)
+		  || (inev->i.mask & IN_IGNORED)))
+	    {
+	      int ret;
+	      bool moved = (inev->i.mask & IN_MOVE_SELF) != 0;
+
+	      if (check_file (finfo) == 0)
+	        {
+		  dbg_log (_("ignored inotify event for `%s` (file exists)"),
+			   finfo->fname);
+		  return;
+		}
+
+	      dbg_log (_("monitored file `%s` was %s, removing watch"),
+		       finfo->fname, moved ? "moved" : "deleted");
+	      /* File was moved out, remove the watch.  Watches are
+		 automatically removed when the file is deleted.  */
+	      if (moved)
+		{
+		  ret = inotify_rm_watch (inotify_fd, inev->i.wd);
+		  if (ret < 0)
+		    dbg_log (_("failed to remove file watch `%s`: %s"),
+			     finfo->fname, strerror (errno));
+		}
+	      finfo->inotify_descr[TRACED_FILE] = -1;
+	      to_clear[dbcnt] = true;
+	      if (finfo->call_res_init)
+	        res_init ();
+	      return;
+	    }
+	  /* The configuration file was open for writing and has just closed.
+	     We reset the cache and reinitialize.  */
+	  if (finfo->inotify_descr[TRACED_FILE] == inev->i.wd
+	      && inev->i.mask & IN_CLOSE_WRITE)
 	    {
 	      /* Mark cache as needing to be cleared and reinitialize.  */
+	      dbg_log (_("monitored file `%s` was written to"), finfo->fname);
 	      to_clear[dbcnt] = true;
 	      if (finfo->call_res_init)
 	        res_init ();
 	      return;
 	    }
+	  /* The parent directory was moved or deleted.  We trigger one last
+	     invalidation.  At the next pruning or invalidation we may add
+	     this watch back if the file is present again.  */
+	  if (finfo->inotify_descr[TRACED_DIR] == inev->i.wd
+	      && ((inev->i.mask & IN_DELETE_SELF)
+		  || (inev->i.mask & IN_MOVE_SELF)
+		  || (inev->i.mask & IN_IGNORED)))
+	    {
+	      bool moved = (inev->i.mask & IN_MOVE_SELF) != 0;
+	      /* The directory watch may have already been removed
+		 but we don't know so we just remove it again and
+		 ignore the error.  Then we remove the file watch.
+		 Note: watches are automatically removed for deleted
+		 files.  */
+	      if (moved)
+		inotify_rm_watch (inotify_fd, inev->i.wd);
+	      if (finfo->inotify_descr[TRACED_FILE] != -1)
+		{
+		  dbg_log (_("monitored parent directory `%s` was %s, removing watch on `%s`"),
+			   finfo->dname, moved ? "moved" : "deleted", finfo->fname);
+		  if (inotify_rm_watch (inotify_fd, finfo->inotify_descr[TRACED_FILE]) < 0)
+		    dbg_log (_("failed to remove file watch `%s`: %s"),
+			     finfo->dname, strerror (errno));
+		}
+	      finfo->inotify_descr[TRACED_FILE] = -1;
+	      finfo->inotify_descr[TRACED_DIR] = -1;
+	      to_clear[dbcnt] = true;
+	      if (finfo->call_res_init)
+	        res_init ();
+	      /* Continue to the next entry since this might be the
+		 parent directory for multiple registered files and
+		 we want to remove watches for all registered files.  */
+	      continue;
+	    }
+	  /* The parent directory had a create or moved to event.  */
+	  if (finfo->inotify_descr[TRACED_DIR] == inev->i.wd
+	      && ((inev->i.mask & IN_MOVED_TO)
+		  || (inev->i.mask & IN_CREATE))
+	      && strcmp (inev->i.name, finfo->sfname) == 0)
+	    {
+	      /* We detected a directory change.  We look for the creation
+		 of the file we are tracking or the move of the same file
+		 into the directory.  */
+	      int ret;
+	      dbg_log (_("monitored file `%s` was %s, adding watch"),
+		       finfo->fname,
+		       inev->i.mask & IN_CREATE ? "created" : "moved into place");
+	      /* File was moved in or created.  Regenerate the watch.  */
+	      if (finfo->inotify_descr[TRACED_FILE] != -1)
+		inotify_rm_watch (inotify_fd,
+				  finfo->inotify_descr[TRACED_FILE]);
+
+	      ret = inotify_add_watch (inotify_fd,
+				       finfo->fname,
+				       TRACED_FILE_MASK);
+	      if (ret < 0)
+		dbg_log (_("failed to add file watch `%s`: %s"),
+			 finfo->fname, strerror (errno));
+
+	      finfo->inotify_descr[TRACED_FILE] = ret;
+
+	      /* The file is new or moved so mark cache as needing to
+		 be cleared and reinitialize.  */
+	      to_clear[dbcnt] = true;
+	      if (finfo->call_res_init)
+		res_init ();
 
+	      /* Done re-adding the watch.  Don't return, we may still
+		 have other files in this same directory, same watch
+		 descriptor, and need to process them.  */
+	    }
+	  /* Other events are ignored, and we move on to the next file.  */
 	  finfo = finfo->next;
         }
     }
@@ -1925,6 +2087,51 @@ clear_db_cache (bool *to_clear)
       }
 }
 
+int
+handle_inotify_events (void)
+{
+  bool to_clear[lastdb] = { false, };
+  union __inev inev;
+
+  /* Read all inotify events for files registered via
+     register_traced_file().  */
+  while (1)
+    {
+      /* Potentially read multiple events into buf.  */
+      ssize_t nb = TEMP_FAILURE_RETRY (read (inotify_fd,
+					     &inev.buf,
+					     sizeof (inev)));
+      if (nb < (ssize_t) sizeof (struct inotify_event))
+	{
+	  /* Not even 1 event.  */
+	  if (__glibc_unlikely (nb == -1 && errno != EAGAIN))
+	    return -1;
+	  /* Done reading events that are ready.  */
+	  break;
+	}
+      /* Process all events.  The normal inotify interface delivers
+	 complete events on a read and never a partial event.  */
+      char *eptr = &inev.buf[0];
+      ssize_t count;
+      while (1)
+	{
+	  /* Check which of the files changed.  */
+	  inotify_check_files (to_clear, &inev);
+	  count = sizeof (struct inotify_event) + inev.i.len;
+	  eptr += count;
+	  nb -= count;
+	  if (nb >= (ssize_t) sizeof (struct inotify_event))
+	    memcpy (&inev, eptr, nb);
+	  else
+	    break;
+	}
+      continue;
+    }
+  /* Actually perform the cache clearing.  */
+  clear_db_cache (to_clear);
+  return 0;
+}
+
 #endif
 
 static void
@@ -2031,42 +2238,20 @@ main_loop_poll (void)
 	    {
 	      if (conns[1].revents != 0)
 		{
-		  bool to_clear[lastdb] = { false, };
-		  union __inev inev;
-
-		  /* Read all inotify events for files registered via
-		     register_traced_file().  */
-		  while (1)
+		  int ret;
+		  ret = handle_inotify_events ();
+		  if (ret == -1)
 		    {
-		      ssize_t nb = TEMP_FAILURE_RETRY (read (inotify_fd, &inev,
-							     sizeof (inev)));
-		      if (nb < (ssize_t) sizeof (struct inotify_event))
-			{
-			  if (__builtin_expect (nb == -1 && errno != EAGAIN,
-						0))
-			    {
-			      /* Something went wrong when reading the inotify
-				 data.  Better disable inotify.  */
-			      dbg_log (_("\
-disabled inotify after read error %d"),
-				       errno);
-			      conns[1].fd = -1;
-			      firstfree = 1;
-			      if (nused == 2)
-				nused = 1;
-			      close (inotify_fd);
-			      inotify_fd = -1;
-			    }
-			  break;
-			}
-
-		      /* Check which of the files changed.  */
-		      inotify_check_files (to_clear, &inev);
+		      /* Something went wrong when reading the inotify
+			 data.  Better disable inotify.  */
+		      dbg_log (_("disabled inotify-based monitoring after read error %d"), errno);
+		      conns[1].fd = -1;
+		      firstfree = 1;
+		      if (nused == 2)
+			nused = 1;
+		      close (inotify_fd);
+		      inotify_fd = -1;
 		    }
-
-		  /* Actually perform the cache clearing.  */
-		  clear_db_cache (to_clear);
-
 		  --n;
 		}
 
@@ -2234,37 +2419,18 @@ main_loop_epoll (int efd)
 # ifdef HAVE_INOTIFY
 	else if (revs[cnt].data.fd == inotify_fd)
 	  {
-	    bool to_clear[lastdb] = { false, };
-	    union __inev inev;
-
-	    /* Read all inotify events for files registered via
-	       register_traced_file().  */
-	    while (1)
+	    int ret;
+	    ret = handle_inotify_events ();
+	    if (ret == -1)
 	      {
-		ssize_t nb = TEMP_FAILURE_RETRY (read (inotify_fd, &inev,
-						 sizeof (inev)));
-		if (nb < (ssize_t) sizeof (struct inotify_event))
-		  {
-		    if (__glibc_unlikely (nb == -1 && errno != EAGAIN))
-		      {
-			/* Something went wrong when reading the inotify
-			   data.  Better disable inotify.  */
-			dbg_log (_("disabled inotify after read error %d"),
-				 errno);
-			(void) epoll_ctl (efd, EPOLL_CTL_DEL, inotify_fd,
-					  NULL);
-			close (inotify_fd);
-			inotify_fd = -1;
-		      }
-		    break;
-		  }
-
-		/* Check which of the files changed.  */
-		inotify_check_files(to_clear, &inev);
+		/* Something went wrong when reading the inotify
+		   data.  Better disable inotify.  */
+		dbg_log (_("disabled inotify-based monitoring after read error %d"), errno);
+		(void) epoll_ctl (efd, EPOLL_CTL_DEL, inotify_fd, NULL);
+		close (inotify_fd);
+		inotify_fd = -1;
+		break;
 	      }
-
-	    /* Actually perform the cache clearing.  */
-	    clear_db_cache (to_clear);
 	  }
 # endif
 # ifdef HAVE_NETLINK
@@ -2301,7 +2467,9 @@ main_loop_epoll (int efd)
 	  no reply in too long of a time.  */
       time_t laststart = now - ACCEPT_TIMEOUT;
       assert (starttime[sock] == 0);
+# ifdef HAVE_INOTIFY
       assert (inotify_fd == -1 || starttime[inotify_fd] == 0);
+# endif
       assert (nl_status_fd == -1 || starttime[nl_status_fd] == 0);
       for (int cnt = highest; cnt > STDERR_FILENO; --cnt)
 	if (starttime[cnt] != 0 && starttime[cnt] < laststart)
diff --git a/nscd/nscd.h b/nscd/nscd.h
index 17a0a96278..75c2eccea0 100644
--- a/nscd/nscd.h
+++ b/nscd/nscd.h
@@ -61,17 +61,67 @@ typedef enum
    80% of the thread stack size.  */
 #define MAX_STACK_USE ((8 * NSCD_THREAD_STACKSIZE) / 10)
 
-
-/* Registered filename used to fill database.  */
+/* Records the file registered per database that when changed
+   or modified requires invalidating the database.  */
 struct traced_file
 {
+  /* Tracks the last modified time of the traced file.  */
   time_t mtime;
+  /* Support multiple registered files per database.  */
   struct traced_file *next;
   int call_res_init;
-  int inotify_descr;
+  /* Requires Inotify support to do anything useful.  */
+#define TRACED_FILE	0
+#define TRACED_DIR	1
+  int inotify_descr[2];
+# ifndef PATH_MAX
+#  define PATH_MAX 1024
+# endif
+  /* The parent directory is used to scan for creation/deletion.  */
+  char dname[PATH_MAX];
+  /* Just the name of the file with no directory component.  */
+  char *sfname;
+  /* The full-path name of the registered file.  */
   char fname[];
 };
 
+/* Initialize a `struct traced_file`.  As input we need the name
+   of the file, and if invalidation requires calling res_init.
+   If CRINIT is 1 then res_init will be called after invalidation
+   or if the traced file is changed in any way, otherwise it will
+   not.  */
+static inline void
+init_traced_file(struct traced_file *file, const char *fname, int crinit)
+{
+   char *dname;
+   file->mtime = 0;
+   file->inotify_descr[TRACED_FILE] = -1;
+   file->inotify_descr[TRACED_DIR] = -1;
+   strcpy (file->fname, fname);
+   /* Compute the parent directory name and store a copy.  The copy makes
+      it much faster to add/remove watches while nscd is running instead
+      of computing this over and over again in a temp buffer.  */
+   file->dname[0] = '\0';
+   dname = strrchr (fname, '/');
+   if (dname != NULL)
+     {
+       size_t len = (size_t)(dname - fname);
+       if (len > sizeof (file->dname))
+	 abort ();
+       strncpy (file->dname, file->fname, len);
+       file->dname[len] = '\0';
+     }
+   /* The basename is the name just after the last forward slash.  */
+   file->sfname = &dname[1];
+   file->call_res_init = crinit;
+}
+
+#define define_traced_file(id, filename) 			\
+static union							\
+{								\
+  struct traced_file file;					\
+  char buf[sizeof (struct traced_file) + sizeof (filename)];	\
+} id##_traced_file;
 
 /* Structure describing dynamic part of one database.  */
 struct database_dyn
@@ -90,7 +140,6 @@ struct database_dyn
   int propagate;
   struct traced_file *traced_files;
   const char *db_filename;
-  time_t file_mtime;
   size_t suggested_module;
   size_t max_db_size;
 
@@ -211,6 +260,9 @@ void do_exit (int child_ret, int errnum, const char *format, ...);
 /* connections.c */
 extern void nscd_init (void);
 extern void register_traced_file (size_t dbidx, struct traced_file *finfo);
+#ifdef HAVE_INOTIFY
+extern void install_watches (struct traced_file *finfo);
+#endif
 extern void close_sockets (void);
 extern void start_threads (void) __attribute__ ((__noreturn__));
 
diff --git a/nss/nss_db/db-init.c b/nss/nss_db/db-init.c
index 041471cad0..099d89b1f8 100644
--- a/nss/nss_db/db-init.c
+++ b/nss/nss_db/db-init.c
@@ -22,35 +22,25 @@
 #include <nscd/nscd.h>
 #include <string.h>
 
-static union
-{
-  struct traced_file file;
-  char buf[sizeof (struct traced_file) + sizeof (_PATH_VARDB "passwd.db")];
-} pwd_traced_file;
-
-static union
-{
-  struct traced_file file;
-  char buf[sizeof (struct traced_file) + sizeof (_PATH_VARDB "group.db")];
-} grp_traced_file;
+#define PWD_FILENAME (_PATH_VARDB "passwd.db")
+define_traced_file (pwd, PWD_FILENAME);
 
-static union
-{
-  struct traced_file file;
-  char buf[sizeof (struct traced_file) + sizeof (_PATH_VARDB "services.db")];
-} serv_traced_file;
+#define GRP_FILENAME (_PATH_VARDB "group.db")
+define_traced_file (grp, GRP_FILENAME);
 
+#define SERV_FILENAME (_PATH_VARDB "services.db")
+define_traced_file (serv, SERV_FILENAME);
 
 void
 _nss_db_init (void (*cb) (size_t, struct traced_file *))
 {
-  strcpy (pwd_traced_file.file.fname,_PATH_VARDB  "passwd.db");
+  init_traced_file (&pwd_traced_file.file, PWD_FILENAME, 0);
   cb (pwddb, &pwd_traced_file.file);
 
-  strcpy (grp_traced_file.file.fname, _PATH_VARDB "group.db");
+  init_traced_file (&grp_traced_file.file, GRP_FILENAME, 0);
   cb (grpdb, &grp_traced_file.file);
 
-  strcpy (serv_traced_file.file.fname, _PATH_VARDB "services.db");
+  init_traced_file (&serv_traced_file.file, SERV_FILENAME, 0);
   cb (servdb, &serv_traced_file.file);
 }
 
diff --git a/nss/nss_files/files-init.c b/nss/nss_files/files-init.c
index 94d440aaa4..72eced41bf 100644
--- a/nss/nss_files/files-init.c
+++ b/nss/nss_files/files-init.c
@@ -21,47 +21,43 @@
 #include <string.h>
 #include <nscd/nscd.h>
 
+#define PWD_FILENAME "/etc/passwd"
+define_traced_file (pwd, PWD_FILENAME);
 
-#define TF(id, filename, ...)					\
-static union							\
-{								\
-  struct traced_file file;					\
-  char buf[sizeof (struct traced_file) + sizeof (filename)];	\
-} id##_traced_file =						\
-  {								\
-    .file =							\
-    {								\
-      __VA_ARGS__						\
-    }								\
-  }
-
-TF (pwd, "/etc/passwd");
-TF (grp, "/etc/group");
-TF (hst, "/etc/hosts");
-TF (resolv, "/etc/resolv.conf", .call_res_init = 1);
-TF (serv, "/etc/services");
-TF (netgr, "/etc/netgroup");
+#define GRP_FILENAME "/etc/group"
+define_traced_file (grp, GRP_FILENAME);
 
+#define HST_FILENAME "/etc/hosts"
+define_traced_file (hst, HST_FILENAME);
+
+#define RESOLV_FILENAME "/etc/resolv.conf"
+define_traced_file (resolv, RESOLV_FILENAME);
+
+#define SERV_FILENAME "/etc/services"
+define_traced_file (serv, SERV_FILENAME);
+
+#define NETGR_FILENAME "/etc/netgroup"
+define_traced_file (netgr, NETGR_FILENAME);
 
 void
 _nss_files_init (void (*cb) (size_t, struct traced_file *))
 {
-  strcpy (pwd_traced_file.file.fname, "/etc/passwd");
+  init_traced_file (&pwd_traced_file.file, PWD_FILENAME, 0);
   cb (pwddb, &pwd_traced_file.file);
 
-  strcpy (grp_traced_file.file.fname, "/etc/group");
+  init_traced_file (&grp_traced_file.file, GRP_FILENAME, 0);
   cb (grpdb, &grp_traced_file.file);
 
-  strcpy (hst_traced_file.file.fname, "/etc/hosts");
+  init_traced_file (&hst_traced_file.file, HST_FILENAME, 0);
   cb (hstdb, &hst_traced_file.file);
 
-  strcpy (resolv_traced_file.file.fname, "/etc/resolv.conf");
+  init_traced_file (&resolv_traced_file.file, RESOLV_FILENAME, 1);
   cb (hstdb, &resolv_traced_file.file);
 
-  strcpy (serv_traced_file.file.fname, "/etc/services");
+  init_traced_file (&serv_traced_file.file, SERV_FILENAME, 0);
   cb (servdb, &serv_traced_file.file);
 
-  strcpy (netgr_traced_file.file.fname, "/etc/netgroup");
+  init_traced_file (&netgr_traced_file.file, NETGR_FILENAME, 0);
   cb (netgrdb, &netgr_traced_file.file);
 }