stdio: Replace _fwalk_reent() with _fwalk_sglue()

Replaced _fwalk_reent() with _fwalk_sglue(). The change adds an
extra __sglue object as a parameter, which will allow the passing
of a global __sglue object separate from the __sglue member of
struct _reent. The global __sglue object will be added in a
follow-on patch.

newlib/libc/include/sys/reent.h

@@ -841,6 +841,9 @@ extern void (*__stdio_exit_handler) (void);
 
 void _reclaim_reent (struct _reent *);
 
+extern int _fwalk_sglue (struct _reent *, int (*)(struct _reent *, __FILE *),
+			 struct _glue *);
+
 /* #define _REENT_ONLY define this to get only reentrant routines */
 
 #if defined(__DYNAMIC_REENT__) && !defined(__SINGLE_THREAD__)

newlib/libc/stdio/fcloseall.c

@@ -59,7 +59,7 @@ Required OS subroutines: <<close>>, <<fstat>>, <<isatty>>, <<lseek>>,
 int
 _fcloseall_r (struct _reent *ptr)
 {
-  return _fwalk_reent (ptr, _fclose_r);
+  return _fwalk_sglue (ptr, _fclose_r, &ptr->__sglue);
 }
 
 #ifndef _REENT_ONLY

newlib/libc/stdio/fflush.c

@@ -286,7 +286,7 @@ int
 fflush (register FILE * fp)
 {
   if (fp == NULL)
-    return _fwalk_reent (_GLOBAL_REENT, _fflush_r);
+    return _fwalk_sglue (_GLOBAL_REENT, _fflush_r, &_GLOBAL_REENT->__sglue);
 
   return _fflush_r (_REENT, fp);
 }

newlib/libc/stdio/findfp.c

@@ -158,7 +158,7 @@ sfmoreglue (struct _reent *d, int n)
 static void
 stdio_exit_handler (void)
 {
-  (void) _fwalk_reent (_GLOBAL_REENT, CLEANUP_FILE);
+  (void) _fwalk_sglue (_GLOBAL_REENT, CLEANUP_FILE, &_GLOBAL_REENT->__sglue);
 }
 
 /*
@@ -240,7 +240,7 @@ cleanup_stdio (struct _reent *ptr)
   if (ptr->_stderr != &__sf[2])
     CLEANUP_FILE (ptr, ptr->_stderr);
 #endif
-  (void) _fwalk_reent (ptr, CLEANUP_FILE);
+  (void) _fwalk_sglue (ptr, CLEANUP_FILE, &ptr->__sglue);
 }
 
 /*
@@ -323,15 +323,21 @@ __fp_unlock (struct _reent * ptr __unused, FILE * fp)
 void
 __fp_lock_all (void)
 {
+  struct _reent *ptr;
+
   __sfp_lock_acquire ();
 
-  (void) _fwalk_reent (_REENT, __fp_lock);
+  ptr = _REENT;
+  (void) _fwalk_sglue (ptr, __fp_lock, &ptr->__sglue);
 }
 
 void
 __fp_unlock_all (void)
 {
-  (void) _fwalk_reent (_REENT, __fp_unlock);
+  struct _reent *ptr;
+
+  ptr = _REENT;
+  (void) _fwalk_sglue (ptr, __fp_unlock, &ptr->__sglue);
 
   __sfp_lock_release ();
 }

newlib/libc/stdio/fwalk.c

@@ -25,15 +25,13 @@ static char sccsid[] = "%W% (Berkeley) %G%";
 #include <stdio.h>
 #include <stdlib.h>
 #include <errno.h>
-#include "local.h"
 
 int
-_fwalk_reent (struct _reent *ptr,
-       register int (*reent_function) (struct _reent *, FILE *))
+_fwalk_sglue (struct _reent *ptr, int (*func) (struct _reent *, FILE *),
+    struct _glue *g)
 {
-  register FILE *fp;
-  register int n, ret = 0;
-  register struct _glue *g;
+  FILE *fp;
+  int n, ret = 0;
 
   /*
    * It should be safe to walk the list without locking it;
@@ -43,10 +41,12 @@ _fwalk_reent (struct _reent *ptr,
    * Avoid locking this list while walking it or else you will
    * introduce a potential deadlock in [at least] refill.c.
    */
-  for (g = &ptr->__sglue; g != NULL; g = g->_next)
+  do {
     for (fp = g->_iobs, n = g->_niobs; --n >= 0; fp++)
       if (fp->_flags != 0 && fp->_flags != 1 && fp->_file != -1)
-	ret |= (*reent_function) (ptr, fp);
+	ret |= (*func) (ptr, fp);
+    g = g->_next;
+  } while (g != NULL);
 
   return ret;
 }

newlib/libc/stdio/local.h

@@ -182,7 +182,6 @@ extern int    __stextmode (int);
 extern void   __sinit (struct _reent *);
 extern void   __smakebuf_r (struct _reent *, FILE *);
 extern int    __swhatbuf_r (struct _reent *, FILE *, size_t *, int *);
-extern int    _fwalk_reent (struct _reent *, int (*)(struct _reent *, FILE *));
 extern int __submore (struct _reent *, FILE *);
 
 #ifdef __LARGE64_FILES

newlib/libc/stdio/refill.c

@@ -102,10 +102,10 @@ __srefill_r (struct _reent * ptr,
    */
   if (fp->_flags & (__SLBF | __SNBF))
     {
-      /* Ignore this file in _fwalk_reent to avoid potential deadlock. */
+      /* Ignore this file in _fwalk_sglue to avoid potential deadlock. */
       short orig_flags = fp->_flags;
       fp->_flags = 1;
-      (void) _fwalk_reent (_GLOBAL_REENT, lflush);
+      (void) _fwalk_sglue (_GLOBAL_REENT, lflush, &_GLOBAL_REENT->__sglue);
       fp->_flags = orig_flags;
 
       /* Now flush this file without locking it. */

winsup/cygwin/syscalls.cc

@@ -63,6 +63,7 @@ details. */
 #include "sync.h"
 #include "child_info.h"
 #include <cygwin/fs.h>  /* needed for RENAME_NOREPLACE */
+#include <sys/reent.h>  /* needed for _fwalk_sglue() declaration */
 
 #undef _close
 #undef _lseek
@@ -3057,9 +3058,6 @@ _cygwin_istext_for_stdio (int fd)
   return 1;
 }
 
-/* internal newlib function */
-extern "C" int _fwalk_reent (struct _reent *ptr, int (*function) (struct _reent *, FILE *));
-
 static int
 setmode_helper (struct _reent *ptr __unused, FILE *f)
 {
@@ -3137,7 +3135,7 @@ cygwin_setmode (int fd, int mode)
 	_my_tls.locals.setmode_mode = O_TEXT;
       else
 	_my_tls.locals.setmode_mode = O_BINARY;
-      _fwalk_reent (_GLOBAL_REENT, setmode_helper);
+      _fwalk_sglue (_GLOBAL_REENT, setmode_helper, &_GLOBAL_REENT->__sglue);
     }
   return res;
 }