lib/gnutls_mbuffers.h

   1 /*
   2  * Copyright (C) 2009 Free Software Foundation
   3  *
   4  * Author: Jonathan Bastien-Filiatrault
   5  *
   6  * This file is part of GNUTLS.
   7  *
   8  * The GNUTLS library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public License
  10  * as published by the Free Software Foundation; either version 2.1 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  21  * USA
  22  *
  23  */
  24
  25 #ifndef GNUTLS_MBUFFERS_H
  26 #define GNUTLS_MBUFFERS_H
  27
  28 #include <gnutls_int.h>
  29 #include <gnutls_errors.h>
  30
  31 void _mbuffer_init (mbuffer_head_st * buf);
  32 void _mbuffer_clear (mbuffer_head_st * buf);
  33 void _mbuffer_enqueue (mbuffer_head_st * buf, mbuffer_st * bufel);
  34 int _mbuffer_remove_bytes (mbuffer_head_st * buf, size_t bytes);
  35 mbuffer_st *_mbuffer_alloc (size_t payload_size, size_t maximum_size);
  36
  37 mbuffer_st *_mbuffer_get_first (mbuffer_head_st * buf, gnutls_datum_t * msg);
  38 mbuffer_st *_mbuffer_get_next (mbuffer_st * cur, gnutls_datum_t * msg);
  39
  40 /* This is dangerous since it will replace bufel with a new
  41  * one.
  42  */
  43 int _mbuffer_append_data (mbuffer_st * bufel, void *newdata,
  44                           size_t newdata_size);
  45 int _mbuffer_linearize (mbuffer_head_st * buf);
  46
  47
  48 /* For "user" use. One can have buffer data and header.
  49  */
  50
  51 inline static void
  52 _mbuffer_set_udata (mbuffer_st * bufel, void *data, size_t data_size)
  53 {
  54   memcpy (bufel->msg.data + bufel->user_mark, data, data_size);
  55 }
  56
  57 inline static void *
  58 _mbuffer_get_uhead_ptr (mbuffer_st * bufel)
  59 {
  60   return bufel->msg.data;
  61 }
  62
  63 inline static void *
  64 _mbuffer_get_udata_ptr (mbuffer_st * bufel)
  65 {
  66   return bufel->msg.data + bufel->user_mark;
  67 }
  68
  69 inline static void
  70 _mbuffer_set_udata_size (mbuffer_st * bufel, size_t size)
  71 {
  72   bufel->msg.size = size + bufel->user_mark;
  73 }
  74
  75 inline static size_t
  76 _mbuffer_get_udata_size (mbuffer_st * bufel)
  77 {
  78   return bufel->msg.size - bufel->user_mark;
  79 }
  80
  81 inline static size_t
  82 _mbuffer_get_uhead_size (mbuffer_st * bufel)
  83 {
  84   return bufel->user_mark;
  85 }
  86
  87 inline static void
  88 _mbuffer_set_uhead_size (mbuffer_st * bufel, size_t size)
  89 {
  90   bufel->user_mark = size;
  91 }
  92
  93
  94
  95 inline static mbuffer_st *
  96 _gnutls_handshake_alloc (size_t size, size_t maximum)
  97 {
  98   mbuffer_st *ret = _mbuffer_alloc (HANDSHAKE_HEADER_SIZE + size,
  99                                     HANDSHAKE_HEADER_SIZE + maximum);
 100
 101   if (!ret)
 102     return NULL;
 103
 104   _mbuffer_set_uhead_size (ret, HANDSHAKE_HEADER_SIZE);
 105
 106   return ret;
 107 }
 108
 109 /* Free a segment, if the pointer is not NULL
 110  *
 111  * We take a ** to detect and fix double free bugs (the dangling
 112  * pointer case). It also makes sure the pointer has a known value
 113  * after freeing.
 114  */
 115 inline static void
 116 _mbuffer_xfree (mbuffer_st ** bufel)
 117 {
 118   if (*bufel)
 119     gnutls_free (*bufel);
 120
 121   *bufel = NULL;
 122 }
 123
 124 #endif