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_put(struct wpabuf *buf, size_t len);
36 struct wpabuf * wpabuf_concat(struct wpabuf *a, struct wpabuf *b);
37 struct wpabuf * wpabuf_zeropad(struct wpabuf *buf, size_t len);
38 void wpabuf_printf(struct wpabuf *buf, char *fmt, ...) PRINTF_FORMAT(2, 3);
39 
40 
41 /**
42  * wpabuf_size - Get the currently allocated size of a wpabuf buffer
43  * @buf: wpabuf buffer
44  * Returns: Currently allocated size of the buffer
45  */
46 static inline size_t wpabuf_size(const struct wpabuf *buf)
47 {
48 	return buf->size;
49 }
50 
51 /**
52  * wpabuf_len - Get the current length of a wpabuf buffer data
53  * @buf: wpabuf buffer
54  * Returns: Currently used length of the buffer
55  */
56 static inline size_t wpabuf_len(const struct wpabuf *buf)
57 {
58 	return buf->used;
59 }
60 
61 /**
62  * wpabuf_tailroom - Get size of available tail room in the end of the buffer
63  * @buf: wpabuf buffer
64  * Returns: Tail room (in bytes) of available space in the end of the buffer
65  */
66 static inline size_t wpabuf_tailroom(const struct wpabuf *buf)
67 {
68 	return buf->size - buf->used;
69 }
70 
71 /**
72  * wpabuf_head - Get pointer to the head of the buffer data
73  * @buf: wpabuf buffer
74  * Returns: Pointer to the head of the buffer data
75  */
76 static inline const void * wpabuf_head(const struct wpabuf *buf)
77 {
78 	return buf->buf;
79 }
80 
81 static inline const u8 * wpabuf_head_u8(const struct wpabuf *buf)
82 {
83 	return wpabuf_head(buf);
84 }
85 
86 /**
87  * wpabuf_mhead - Get modifiable pointer to the head of the buffer data
88  * @buf: wpabuf buffer
89  * Returns: Pointer to the head of the buffer data
90  */
91 static inline void * wpabuf_mhead(struct wpabuf *buf)
92 {
93 	return buf->buf;
94 }
95 
96 static inline u8 * wpabuf_mhead_u8(struct wpabuf *buf)
97 {
98 	return wpabuf_mhead(buf);
99 }
100 
101 static inline void wpabuf_put_u8(struct wpabuf *buf, u8 data)
102 {
103 	u8 *pos = wpabuf_put(buf, 1);
104 	*pos = data;
105 }
106 
107 static inline void wpabuf_put_le16(struct wpabuf *buf, u16 data)
108 {
109 	u8 *pos = wpabuf_put(buf, 2);
110 	WPA_PUT_LE16(pos, data);
111 }
112 
113 static inline void wpabuf_put_le32(struct wpabuf *buf, u32 data)
114 {
115 	u8 *pos = wpabuf_put(buf, 4);
116 	WPA_PUT_LE32(pos, data);
117 }
118 
119 static inline void wpabuf_put_be16(struct wpabuf *buf, u16 data)
120 {
121 	u8 *pos = wpabuf_put(buf, 2);
122 	WPA_PUT_BE16(pos, data);
123 }
124 
125 static inline void wpabuf_put_be24(struct wpabuf *buf, u32 data)
126 {
127 	u8 *pos = wpabuf_put(buf, 3);
128 	WPA_PUT_BE24(pos, data);
129 }
130 
131 static inline void wpabuf_put_be32(struct wpabuf *buf, u32 data)
132 {
133 	u8 *pos = wpabuf_put(buf, 4);
134 	WPA_PUT_BE32(pos, data);
135 }
136 
137 static inline void wpabuf_put_data(struct wpabuf *buf, const void *data,
138 				   size_t len)
139 {
140 	if (data)
141 		os_memcpy(wpabuf_put(buf, len), data, len);
142 }
143 
144 static inline void wpabuf_put_buf(struct wpabuf *dst,
145 				  const struct wpabuf *src)
146 {
147 	wpabuf_put_data(dst, wpabuf_head(src), wpabuf_len(src));
148 }
149 
150 static inline void wpabuf_set(struct wpabuf *buf, const void *data, size_t len)
151 {
152 	buf->buf = (u8 *) data;
153 	buf->flags = WPABUF_FLAG_EXT_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 */
163