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diff --git a/lib/vio_fifo.h b/lib/vio_fifo.h
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+/* VTY I/O FIFO -- header
+ * Copyright (C) 2010 Chris Hall (GMCH), Highwayman
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2, or (at your
+ * option) any later version.
+ *
+ * GNU Zebra is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING.  If not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef _ZEBRA_VIO_FIFO_H
+#define _ZEBRA_VIO_FIFO_H
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "list_util.h"
+#include "zassert.h"
+
+#ifndef Inline                  /* in case of compiler issues           */
+#define Inline static inline
+#endif
+
+#ifndef Private                 /* extern, but for "friends" only       */
+#define Private extern
+#endif
+
+/*==============================================================================
+ * VTY I/O FIFO -- buffering of arbitrary amounts of I/O.
+ */
+
+#ifdef  NDEBUG
+# define  VIO_FIFO_DEBUG 0      /* NDEBUG override                      */
+#else
+# ifndef VIO_FIFO_DEBUG
+#  define VIO_FIFO_DEBUG 1      /* Set to 1 to turn on debug checks     */
+# endif
+#endif
+
+/*==============================================================================
+ * Data Structures
+ */
+typedef struct vio_fifo  vio_fifo_t ;
+typedef struct vio_fifo* vio_fifo ;
+
+typedef struct vio_fifo_lump  vio_fifo_lump_t ;
+typedef struct vio_fifo_lump* vio_fifo_lump ;
+
+struct vio_fifo
+{
+  struct dl_base_pair(vio_fifo_lump) base ;
+
+  bool    one ;
+
+  char*   put_ptr ;
+  char*   put_end ;
+
+  char*   get_ptr ;
+  char*   get_end ;
+
+  size_t  size ;
+} ;
+
+struct vio_fifo_lump
+{
+  struct dl_list_pair(vio_fifo_lump) list ;
+
+  char*   end ;         /* end of this particular lump  */
+  char    data[] ;
+} ;
+
+/*==============================================================================
+ * Functions
+ */
+
+extern vio_fifo
+vio_fifo_init_new(vio_fifo vf, size_t size) ;
+
+extern vio_fifo
+vio_fifo_reset(vio_fifo vf, int free_structure) ;
+
+#define vio_fifo_reset_keep(vf) vio_fifo_reset(vf, 0)
+#define vio_fifo_reset_free(vf) vio_fifo_reset(vf, 1)
+
+extern void
+vio_fifo_set_empty(vio_fifo vf) ;
+
+Inline bool
+vio_fifo_empty(vio_fifo vf) ;
+
+extern void
+vio_fifo_put(vio_fifo vf, const char* src, size_t n) ;
+
+Inline void
+vio_fifo_put_byte(vio_fifo vf, char b) ;
+
+extern size_t
+vio_fifo_get(vio_fifo vf, void* dst, size_t n) ;
+
+Inline int
+vio_fifo_get_byte(vio_fifo vf) ;
+
+extern void*
+vio_fifo_get_lump(vio_fifo vf, size_t* have) ;
+
+extern void
+vio_fifo_got_upto(vio_fifo vf, void* here) ;
+
+
+Private void
+vio_fifo_lump_new(vio_fifo vf) ;
+
+Private int
+vio_fifo_get_next_byte(vio_fifo vf) ;
+
+/*==============================================================================
+ * Debug -- verification function
+ */
+
+Private void
+vio_fifo_verify(vio_fifo vf) ;
+
+#if VIO_FIFO_DEBUG
+# define VIO_FIFO_DEBUG_VERIFY(vf) vio_fifo_verify(vf)
+#else
+# define VIO_FIFO_DEBUG_VERIFY(vf)
+#endif
+
+/*==============================================================================
+ * Inline Functions
+ */
+
+/*------------------------------------------------------------------------------
+ * Returns true <=> FIFO is empty
+ */
+Inline bool
+vio_fifo_empty(vio_fifo vf)
+{
+  return (vf->get_ptr == vf->put_ptr) ;
+}
+
+/*------------------------------------------------------------------------------
+ * Put one byte to the FIFO
+ */
+Inline void
+vio_fifo_put_byte(vio_fifo vf, char b)
+{
+  if (vf->put_ptr >= vf->put_end)
+    vio_fifo_lump_new(vf) ;   /* traps broken vf->put_ptr > vf->put_end */
+
+  VIO_FIFO_DEBUG_VERIFY(vf) ;
+
+  *vf->put_ptr++ = b ;
+} ;
+
+/*------------------------------------------------------------------------------
+ * Get one byte from the FIFO.
+ *
+ * Returns: 0x00..0xFF -- byte value     (as an int)
+ *          -1         => FIFO is empty.
+ */
+Inline int
+vio_fifo_get_byte(vio_fifo vf)
+{
+  if (vf->get_end <= (vf->get_ptr + 1))
+    return vio_fifo_get_next_byte(vf) ;
+
+  VIO_FIFO_DEBUG_VERIFY(vf) ;
+
+  return (unsigned char)*vf->get_ptr++ ;
+} ;
+
+#endif /* _ZEBRA_VIO_FIFO_H */