[rtems commit] Synchronize all file descriptors in sync()

[Sebastian Huber]

Module:    rtems
Branch:    5
Commit:    8d54187a19f6e6d2849066f80254730302482934
Changeset: http://git.rtems.org/rtems/commit/?id=8d54187a19f6e6d2849066f80254730302482934

Author:    Sebastian Huber <sebastian.huber at embedded-brains.de>
Date:      Fri May 13 13:10:00 2022 +0200

Synchronize all file descriptors in sync()

Synchronize all file descriptors and not just the ones associated with a FILE
object.

Close #4655.

---

 cpukit/libcsupport/src/sync.c | 93 ++++++-------------------------------------
 1 file changed, 12 insertions(+), 81 deletions(-)

diff --git a/cpukit/libcsupport/src/sync.c b/cpukit/libcsupport/src/sync.c
index 265c6f07c9..0ea77422f1 100644
--- a/cpukit/libcsupport/src/sync.c
+++ b/cpukit/libcsupport/src/sync.c
@@ -1,13 +1,13 @@
 /**
- *  @file
+ * @file
  *
- *  @brief Synchronize Data on Disk with Memory 
- *  @ingroup libcsupport
+ * @ingroup libcsupport
+ *
+ * @brief This source file contains the implementation of sync().
  */
 
 /*
- *  COPYRIGHT (c) 1989-2008.
- *  On-Line Applications Research Corporation (OAR).
+ * Copyright (C) 2022 embedded brains GmbH
  *
  *  The license and distribution terms for this file may be
  *  found in the file LICENSE in this distribution or at
@@ -18,85 +18,16 @@
 #include "config.h"
 #endif
 
-/* Since we compile with strict ANSI we need to undef it to get
- * prototypes for extensions
- */
-#undef __STRICT_ANSI__
-int fdatasync(int);        /* still not always prototyped */
-
-
 #include <unistd.h>
-#include <stdio.h>
-
-#include <rtems.h>
-#include <rtems/score/thread.h>
-#include <rtems/score/percpu.h>
-
-/* XXX check standards -- Linux version appears to be void */
-void _fwalk(struct _reent *, void *);
-
-
-static void sync_wrapper(FILE *f)
-{
-  int fn = fileno(f);
-
-  /*
-   * There is no way to report errors here.  So this is a best-effort approach.
-   */
-  (void) fsync(fn);
-  (void) fdatasync(fn);
-}
 
-/* iterate over all FILE *'s for this thread */
-static bool sync_per_thread(Thread_Control *t, void *arg)
-{
-   struct _reent *current_reent;
-   struct _reent *this_reent;
-
-   /*
-    *  The sync_wrapper() function will operate on the current thread's
-    *  reent structure so we will temporarily use that.
-    */
-   this_reent = t->libc_reent;
-   if ( this_reent ) {
-     Thread_Control *executing = _Thread_Get_executing();
-     current_reent = executing->libc_reent;
-     executing->libc_reent = this_reent;
-     _fwalk (t->libc_reent, sync_wrapper);
-     executing->libc_reent = current_reent;
-   }
-
-   return false;
-}
+#include <rtems/libio_.h>
 
-/*
- * _global_impure_ptr is not prototyped in any .h files.
- * We have to extern it here.
- */
-extern struct _reent * const _global_impure_ptr __ATTRIBUTE_IMPURE_PTR__;
-
-/**
- * This function operates by as follows:
- *    for all threads
- *      for all FILE *
- *         fsync()
- *         fdatasync()
- */
-void sync(void)
+void sync( void )
 {
+  int fd;
 
-  /*
-   *  Walk the one used initially by RTEMS.
-   */
-  _fwalk(_global_impure_ptr, sync_wrapper);
-
-  /*
-   *  XXX Do we walk the one used globally by newlib?
-   *  XXX Do we need the RTEMS global one?
-   */
-
-  /*
-   *  Now walk all the per-thread reentrancy structures.
-   */
-  rtems_task_iterate(sync_per_thread, NULL);
+  for ( fd = 0; fd < (int) rtems_libio_number_iops; ++fd ) {
+    (void) fsync( fd );
+    (void) fdatasync( fd );
+  }
 }