buffer.h revision 57429 
1/*
2 *
3 * buffer.h
4 *
5 * Author: Tatu Ylonen <ylo@cs.hut.fi>
6 *
7 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
8 *                    All rights reserved
9 *
10 * Created: Sat Mar 18 04:12:25 1995 ylo
11 *
12 * Code for manipulating FIFO buffers.
13 *
14 */
15
16/* RCSID("$Id: buffer.h,v 1.3 1999/11/24 19:53:44 markus Exp $"); */
17
18#ifndef BUFFER_H
19#define BUFFER_H
20
21typedef struct {
22	char   *buf;		/* Buffer for data. */
23	unsigned int alloc;	/* Number of bytes allocated for data. */
24	unsigned int offset;	/* Offset of first byte containing data. */
25	unsigned int end;	/* Offset of last byte containing data. */
26}       Buffer;
27/* Initializes the buffer structure. */
28void    buffer_init(Buffer * buffer);
29
30/* Frees any memory used for the buffer. */
31void    buffer_free(Buffer * buffer);
32
33/* Clears any data from the buffer, making it empty.  This does not actually
34   zero the memory. */
35void    buffer_clear(Buffer * buffer);
36
37/* Appends data to the buffer, expanding it if necessary. */
38void    buffer_append(Buffer * buffer, const char *data, unsigned int len);
39
40/*
41 * Appends space to the buffer, expanding the buffer if necessary. This does
42 * not actually copy the data into the buffer, but instead returns a pointer
43 * to the allocated region.
44 */
45void    buffer_append_space(Buffer * buffer, char **datap, unsigned int len);
46
47/* Returns the number of bytes of data in the buffer. */
48unsigned int buffer_len(Buffer * buffer);
49
50/* Gets data from the beginning of the buffer. */
51void    buffer_get(Buffer * buffer, char *buf, unsigned int len);
52
53/* Consumes the given number of bytes from the beginning of the buffer. */
54void    buffer_consume(Buffer * buffer, unsigned int bytes);
55
56/* Consumes the given number of bytes from the end of the buffer. */
57void    buffer_consume_end(Buffer * buffer, unsigned int bytes);
58
59/* Returns a pointer to the first used byte in the buffer. */
60char   *buffer_ptr(Buffer * buffer);
61
62/*
63 * Dumps the contents of the buffer to stderr in hex.  This intended for
64 * debugging purposes only.
65 */
66void    buffer_dump(Buffer * buffer);
67
68#endif				/* BUFFER_H */
69