src/utils/wpabuf.h

   1 /*
   2  * Dynamic data buffer
   3  * Copyright (c) 2007-2009, 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 struct wpabuf * wpabuf_zeropad(struct wpabuf *buf, size_t len);
  41 void wpabuf_printf(struct wpabuf *buf, char *fmt, ...) PRINTF_FORMAT(2, 3);
  42
  43
  44 /**
  45  * wpabuf_size - Get the currently allocated size of a wpabuf buffer
  46  * @buf: wpabuf buffer
  47  * Returns: Currently allocated size of the buffer
  48  */
  49 static inline size_t wpabuf_size(const struct wpabuf *buf)
  50 {
  51         return buf->size;
  52 }
  53
  54 /**
  55  * wpabuf_len - Get the current length of a wpabuf buffer data
  56  * @buf: wpabuf buffer
  57  * Returns: Currently used length of the buffer
  58  */
  59 static inline size_t wpabuf_len(const struct wpabuf *buf)
  60 {
  61         return buf->used;
  62 }
  63
  64 /**
  65  * wpabuf_tailroom - Get size of available tail room in the end of the buffer
  66  * @buf: wpabuf buffer
  67  * Returns: Tail room (in bytes) of available space in the end of the buffer
  68  */
  69 static inline size_t wpabuf_tailroom(const struct wpabuf *buf)
  70 {
  71         return buf->size - buf->used;
  72 }
  73
  74 /**
  75  * wpabuf_head - Get pointer to the head of the buffer data
  76  * @buf: wpabuf buffer
  77  * Returns: Pointer to the head of the buffer data
  78  */
  79 static inline const void * wpabuf_head(const struct wpabuf *buf)
  80 {
  81         if (buf->ext_data)
  82                 return buf->ext_data;
  83         return buf + 1;
  84 }
  85
  86 static inline const u8 * wpabuf_head_u8(const struct wpabuf *buf)
  87 {
  88         return wpabuf_head(buf);
  89 }
  90
  91 /**
  92  * wpabuf_mhead - Get modifiable pointer to the head of the buffer data
  93  * @buf: wpabuf buffer
  94  * Returns: Pointer to the head of the buffer data
  95  */
  96 static inline void * wpabuf_mhead(struct wpabuf *buf)
  97 {
  98         if (buf->ext_data)
  99                 return buf->ext_data;
 100         return buf + 1;
 101 }
 102
 103 static inline u8 * wpabuf_mhead_u8(struct wpabuf *buf)
 104 {
 105         return wpabuf_mhead(buf);
 106 }
 107
 108 static inline void wpabuf_put_u8(struct wpabuf *buf, u8 data)
 109 {
 110         u8 *pos = wpabuf_put(buf, 1);
 111         *pos = data;
 112 }
 113
 114 static inline void wpabuf_put_le16(struct wpabuf *buf, u16 data)
 115 {
 116         u8 *pos = wpabuf_put(buf, 2);
 117         WPA_PUT_LE16(pos, data);
 118 }
 119
 120 static inline void wpabuf_put_be16(struct wpabuf *buf, u16 data)
 121 {
 122         u8 *pos = wpabuf_put(buf, 2);
 123         WPA_PUT_BE16(pos, data);
 124 }
 125
 126 static inline void wpabuf_put_be24(struct wpabuf *buf, u32 data)
 127 {
 128         u8 *pos = wpabuf_put(buf, 3);
 129         WPA_PUT_BE24(pos, data);
 130 }
 131
 132 static inline void wpabuf_put_be32(struct wpabuf *buf, u32 data)
 133 {
 134         u8 *pos = wpabuf_put(buf, 4);
 135         WPA_PUT_BE32(pos, data);
 136 }
 137
 138 static inline void wpabuf_put_data(struct wpabuf *buf, const void *data,
 139                                    size_t len)
 140 {
 141         if (data)
 142                 os_memcpy(wpabuf_put(buf, len), data, len);
 143 }
 144
 145 static inline void wpabuf_put_buf(struct wpabuf *dst,
 146                                   const struct wpabuf *src)
 147 {
 148         wpabuf_put_data(dst, wpabuf_head(src), wpabuf_len(src));
 149 }
 150
 151 static inline void wpabuf_set(struct wpabuf *buf, const void *data, size_t len)
 152 {
 153         buf->ext_data = (u8 *) data;
 154         buf->size = buf->used = len;
 155 }
 156
 157 static inline void wpabuf_put_str(struct wpabuf *dst, const char *str)
 158 {
 159         wpabuf_put_data(dst, str, os_strlen(str));
 160 }
 161
 162 #endif /* WPABUF_H */