lib/bufdir/fbuf.h

   1 /*
   2  * Copyright (c) 1995 - 2000, 2002, 2004 - 2006 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /* $Id$ */
  35
  36 #ifndef _FBUF_H_
  37 #define _FBUF_H_
  38
  39 typedef enum {
  40     FBUF_READ     = 0x01,
  41     FBUF_WRITE    = 0x02
  42 } fbuf_flags;
  43
  44 struct fbuf;
  45 typedef struct fbuf fbuf;
  46
  47 typedef int (*fbuf_truncate_func)(fbuf *fbuf, size_t new_len);
  48
  49 struct fbuf {
  50     void *buf;
  51     size_t len;
  52     fbuf_flags flags;
  53     fbuf_truncate_func truncate; /* _not_ optional */
  54     void *data;
  55 };
  56
  57 /* defauls for create and end, implementations roll their own */
  58 #ifdef _KERNEL
  59 int fbuf_create (fbuf *fbuf, NNPFS_FBUF_HANDLE fd, size_t len, fbuf_flags flags);
  60 #else
  61 int fbuf_create (fbuf *fbuf, int fd, size_t len, fbuf_flags flags);
  62 #endif
  63
  64 int fbuf_end (fbuf *fbuf);
  65
  66 /* the actual fbuf interface */
  67 int fbuf_truncate (fbuf *fbuf, size_t new_len);
  68 size_t fbuf_len (fbuf *f);
  69 void *fbuf_buf (fbuf *f);
  70
  71 #ifndef _KERNEL
  72 int copyrx2fd (struct rx_call *call, int fd, off_t off, off_t len);
  73 int copyfd2rx (int fd, struct rx_call *call, off_t off, off_t len);
  74 #endif
  75
  76 #endif /* _FBUF_H_ */