dist/wpa/src/utils/wpabuf.h

   1 /*
   2  * Dynamic data buffer
   3  * Copyright (c) 2007, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #ifndef WPABUF_H
  16 #define WPABUF_H
  17
  18 /*
  19  * Internal data structure for wpabuf. Please do not touch this directly from
  20  * elsewhere. This is only defined in header file to allow inline functions
  21  * from this file to access data.
  22  */
  23 struct wpabuf {
  24         size_t size; /* total size of the allocated buffer */
  25         size_t used; /* length of data in the buffer */
  26         u8 *ext_data; /* pointer to external data; NULL if data follows
  27                        * struct wpabuf */
  28         /* optionally followed by the allocated buffer */
  29 };
  30
  31
  32 int wpabuf_resize(struct wpabuf **buf, size_t add_len);
  33 struct wpabuf * wpabuf_alloc(size_t len);
  34 struct wpabuf * wpabuf_alloc_ext_data(u8 *data, size_t len);
  35 struct wpabuf * wpabuf_alloc_copy(const void *data, size_t len);
  36 struct wpabuf * wpabuf_dup(const struct wpabuf *src);
  37 void wpabuf_free(struct wpabuf *buf);
  38 void * wpabuf_put(struct wpabuf *buf, size_t len);
  39 struct wpabuf * wpabuf_concat(struct wpabuf *a, struct wpabuf *b);
  40
  41
  42 /**
  43  * wpabuf_size - Get the currently allocated size of a wpabuf buffer
  44  * @buf: wpabuf buffer
  45  * Returns: Currently allocated size of the buffer
  46  */
  47 static inline size_t wpabuf_size(const struct wpabuf *buf)
  48 {
  49         return buf->size;
  50 }
  51
  52 /**
  53  * wpabuf_len - Get the current length of a wpabuf buffer data
  54  * @buf: wpabuf buffer
  55  * Returns: Currently used length of the buffer
  56  */
  57 static inline size_t wpabuf_len(const struct wpabuf *buf)
  58 {
  59         return buf->used;
  60 }
  61
  62 /**
  63  * wpabuf_tailroom - Get size of available tail room in the end of the buffer
  64  * @buf: wpabuf buffer
  65  * Returns: Tail room (in bytes) of available space in the end of the buffer
  66  */
  67 static inline size_t wpabuf_tailroom(const struct wpabuf *buf)
  68 {
  69         return buf->size - buf->used;
  70 }
  71
  72 /**
  73  * wpabuf_head - Get pointer to the head of the buffer data
  74  * @buf: wpabuf buffer
  75  * Returns: Pointer to the head of the buffer data
  76  */
  77 static inline const void * wpabuf_head(const struct wpabuf *buf)
  78 {
  79         if (buf->ext_data)
  80                 return buf->ext_data;
  81         return buf + 1;
  82 }
  83
  84 static inline const u8 * wpabuf_head_u8(const struct wpabuf *buf)
  85 {
  86         return wpabuf_head(buf);
  87 }
  88
  89 /**
  90  * wpabuf_mhead - Get modifiable pointer to the head of the buffer data
  91  * @buf: wpabuf buffer
  92  * Returns: Pointer to the head of the buffer data
  93  */
  94 static inline void * wpabuf_mhead(struct wpabuf *buf)
  95 {
  96         if (buf->ext_data)
  97                 return buf->ext_data;
  98         return buf + 1;
  99 }
 100
 101 static inline u8 * wpabuf_mhead_u8(struct wpabuf *buf)
 102 {
 103         return wpabuf_mhead(buf);
 104 }
 105
 106 static inline void wpabuf_put_u8(struct wpabuf *buf, u8 data)
 107 {
 108         u8 *pos = wpabuf_put(buf, 1);
 109         *pos = data;
 110 }
 111
 112 static inline void wpabuf_put_be16(struct wpabuf *buf, u16 data)
 113 {
 114         u8 *pos = wpabuf_put(buf, 2);
 115         WPA_PUT_BE16(pos, data);
 116 }
 117
 118 static inline void wpabuf_put_be24(struct wpabuf *buf, u32 data)
 119 {
 120         u8 *pos = wpabuf_put(buf, 3);
 121         WPA_PUT_BE24(pos, data);
 122 }
 123
 124 static inline void wpabuf_put_be32(struct wpabuf *buf, u32 data)
 125 {
 126         u8 *pos = wpabuf_put(buf, 4);
 127         WPA_PUT_BE32(pos, data);
 128 }
 129
 130 static inline void wpabuf_put_data(struct wpabuf *buf, const void *data,
 131                                    size_t len)
 132 {
 133         if (data)
 134                 os_memcpy(wpabuf_put(buf, len), data, len);
 135 }
 136
 137 static inline void wpabuf_put_buf(struct wpabuf *dst,
 138                                   const struct wpabuf *src)
 139 {
 140         wpabuf_put_data(dst, wpabuf_head(src), wpabuf_len(src));
 141 }
 142
 143 static inline void wpabuf_set(struct wpabuf *buf, const void *data, size_t len)
 144 {
 145         buf->ext_data = (u8 *) data;
 146         buf->size = buf->used = len;
 147 }
 148
 149 #endif /* WPABUF_H */