1 /*
2  * Dynamic data buffer
3  * Copyright (c) 2007-2012, Jouni Malinen <j@w1.fi>
4  *
5  * This software may be distributed under the terms of the BSD license.
6  * See README for more details.
7  */
8 
9 #ifndef WPABUF_H
10 #define WPABUF_H
11 
12 /* wpabuf::buf is a pointer to external data */
13 #define WPABUF_FLAG_EXT_DATA BIT(0)
14 
15 /*
16  * Internal data structure for wpabuf. Please do not touch this directly from
17  * elsewhere. This is only defined in header file to allow inline functions
18  * from this file to access data.
19  */
20 struct wpabuf {
21 	size_t size; /* total size of the allocated buffer */
22 	size_t used; /* length of data in the buffer */
23 	u8 *buf; /* pointer to the head of the buffer */
24 	unsigned int flags;
25 	/* optionally followed by the allocated buffer */
26 };
27 
28 
29 int wpabuf_resize(struct wpabuf **buf, size_t add_len);
30 struct wpabuf * wpabuf_alloc(size_t len);
31 struct wpabuf * wpabuf_alloc_ext_data(u8 *data, size_t len);
32 struct wpabuf * wpabuf_alloc_copy(const void *data, size_t len);
33 struct wpabuf * wpabuf_dup(const struct wpabuf *src);
34 void wpabuf_free(struct wpabuf *buf);
35 void wpabuf_clear_free(struct wpabuf *buf);
36 void * wpabuf_put(struct wpabuf *buf, size_t len);
37 struct wpabuf * wpabuf_concat(struct wpabuf *a, struct wpabuf *b);
38 struct wpabuf * wpabuf_zeropad(struct wpabuf *buf, size_t len);
39 void wpabuf_printf(struct wpabuf *buf, char *fmt, ...) PRINTF_FORMAT(2, 3);
40 struct wpabuf * wpabuf_parse_bin(const char *buf);
41 
42 
43 /**
44  * wpabuf_size - Get the currently allocated size of a wpabuf buffer
45  * @buf: wpabuf buffer
46  * Returns: Currently allocated size of the buffer
47  */
48 static inline size_t wpabuf_size(const struct wpabuf *buf)
49 {
50 	return buf->size;
51 }
52 
53 /**
54  * wpabuf_len - Get the current length of a wpabuf buffer data
55  * @buf: wpabuf buffer
56  * Returns: Currently used length of the buffer
57  */
58 static inline size_t wpabuf_len(const struct wpabuf *buf)
59 {
60 	return buf->used;
61 }
62 
63 /**
64  * wpabuf_tailroom - Get size of available tail room in the end of the buffer
65  * @buf: wpabuf buffer
66  * Returns: Tail room (in bytes) of available space in the end of the buffer
67  */
68 static inline size_t wpabuf_tailroom(const struct wpabuf *buf)
69 {
70 	return buf->size - buf->used;
71 }
72 
73 /**
74  * wpabuf_head - Get pointer to the head of the buffer data
75  * @buf: wpabuf buffer
76  * Returns: Pointer to the head of the buffer data
77  */
78 static inline const void * wpabuf_head(const struct wpabuf *buf)
79 {
80 	return buf->buf;
81 }
82 
83 static inline const u8 * wpabuf_head_u8(const struct wpabuf *buf)
84 {
85 	return (const u8 *) wpabuf_head(buf);
86 }
87 
88 /**
89  * wpabuf_mhead - Get modifiable pointer to the head of the buffer data
90  * @buf: wpabuf buffer
91  * Returns: Pointer to the head of the buffer data
92  */
93 static inline void * wpabuf_mhead(struct wpabuf *buf)
94 {
95 	return buf->buf;
96 }
97 
98 static inline u8 * wpabuf_mhead_u8(struct wpabuf *buf)
99 {
100 	return (u8 *) wpabuf_mhead(buf);
101 }
102 
103 static inline void wpabuf_put_u8(struct wpabuf *buf, u8 data)
104 {
105 	u8 *pos = (u8 *) wpabuf_put(buf, 1);
106 	*pos = data;
107 }
108 
109 static inline void wpabuf_put_le16(struct wpabuf *buf, u16 data)
110 {
111 	u8 *pos = (u8 *) wpabuf_put(buf, 2);
112 	WPA_PUT_LE16(pos, data);
113 }
114 
115 static inline void wpabuf_put_le32(struct wpabuf *buf, u32 data)
116 {
117 	u8 *pos = (u8 *) wpabuf_put(buf, 4);
118 	WPA_PUT_LE32(pos, data);
119 }
120 
121 static inline void wpabuf_put_be16(struct wpabuf *buf, u16 data)
122 {
123 	u8 *pos = (u8 *) wpabuf_put(buf, 2);
124 	WPA_PUT_BE16(pos, data);
125 }
126 
127 static inline void wpabuf_put_be24(struct wpabuf *buf, u32 data)
128 {
129 	u8 *pos = (u8 *) wpabuf_put(buf, 3);
130 	WPA_PUT_BE24(pos, data);
131 }
132 
133 static inline void wpabuf_put_be32(struct wpabuf *buf, u32 data)
134 {
135 	u8 *pos = (u8 *) wpabuf_put(buf, 4);
136 	WPA_PUT_BE32(pos, data);
137 }
138 
139 static inline void wpabuf_put_data(struct wpabuf *buf, const void *data,
140 				   size_t len)
141 {
142 	if (data)
143 		os_memcpy(wpabuf_put(buf, len), data, len);
144 }
145 
146 static inline void wpabuf_put_buf(struct wpabuf *dst,
147 				  const struct wpabuf *src)
148 {
149 	wpabuf_put_data(dst, wpabuf_head(src), wpabuf_len(src));
150 }
151 
152 static inline void wpabuf_set(struct wpabuf *buf, const void *data, size_t len)
153 {
154 	buf->buf = (u8 *) data;
155 	buf->flags = WPABUF_FLAG_EXT_DATA;
156 	buf->size = buf->used = len;
157 }
158 
159 static inline void wpabuf_put_str(struct wpabuf *dst, const char *str)
160 {
161 	wpabuf_put_data(dst, str, os_strlen(str));
162 }
163 
164 #endif /* WPABUF_H */
165