1/* $NetBSD: citrus_memstream.h,v 1.3 2005/05/14 17:55:42 tshiozak Exp $ */
2
3/*-
4 * SPDX-License-Identifier: BSD-2-Clause
5 *
6 * Copyright (c)2003 Citrus Project,
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 */
31
32#ifndef _CITRUS_MEMSTREAM_H_
33#define _CITRUS_MEMSTREAM_H_
34
35struct _citrus_memory_stream {
36	struct _citrus_region	ms_region;
37	size_t			ms_pos;
38};
39
40__BEGIN_DECLS
41const char	*_citrus_memory_stream_getln(
42		    struct _citrus_memory_stream * __restrict,
43		    size_t * __restrict);
44const char	*_citrus_memory_stream_matchline(
45		    struct _citrus_memory_stream * __restrict,
46		    const char * __restrict, size_t * __restrict, int);
47void		*_citrus_memory_stream_chr(struct _citrus_memory_stream *,
48		    struct _citrus_region *, char);
49void		_citrus_memory_stream_skip_ws(struct _citrus_memory_stream *);
50__END_DECLS
51
52static __inline int
53_citrus_memory_stream_iseof(struct _citrus_memory_stream *ms)
54{
55
56	return (ms->ms_pos >= _citrus_region_size(&ms->ms_region));
57}
58
59static __inline void
60_citrus_memory_stream_bind(struct _citrus_memory_stream * __restrict ms,
61    const struct _citrus_region * __restrict r)
62{
63
64	ms->ms_region = *r;
65	ms->ms_pos = 0;
66}
67
68static __inline void
69_citrus_memory_stream_bind_ptr(struct _citrus_memory_stream * __restrict ms,
70    void *ptr, size_t sz)
71{
72	struct _citrus_region r;
73
74	_citrus_region_init(&r, ptr, sz);
75	_citrus_memory_stream_bind(ms, &r);
76}
77
78static __inline void
79_citrus_memory_stream_rewind(struct _citrus_memory_stream *ms)
80{
81
82	ms->ms_pos = 0;
83}
84
85static __inline size_t
86_citrus_memory_stream_tell(struct _citrus_memory_stream *ms)
87{
88
89	return (ms->ms_pos);
90}
91
92static __inline size_t
93_citrus_memory_stream_remainder(struct _citrus_memory_stream *ms)
94{
95	size_t sz;
96
97	sz = _citrus_region_size(&ms->ms_region);
98	if (ms->ms_pos>sz)
99		return (0);
100	return (sz-ms->ms_pos);
101}
102
103static __inline int
104_citrus_memory_stream_seek(struct _citrus_memory_stream *ms, size_t pos, int w)
105{
106	size_t sz;
107
108	sz = _citrus_region_size(&ms->ms_region);
109
110	switch (w) {
111	case SEEK_SET:
112		if (pos >= sz)
113			return (-1);
114		ms->ms_pos = pos;
115		break;
116	case SEEK_CUR:
117		pos += (ssize_t)ms->ms_pos;
118		if (pos >= sz)
119			return (-1);
120		ms->ms_pos = pos;
121		break;
122	case SEEK_END:
123		if (sz < pos)
124			return (-1);
125		ms->ms_pos = sz - pos;
126		break;
127	}
128	return (0);
129}
130
131static __inline int
132_citrus_memory_stream_getc(struct _citrus_memory_stream *ms)
133{
134
135	if (_citrus_memory_stream_iseof(ms))
136		return (EOF);
137	return (_citrus_region_peek8(&ms->ms_region, ms->ms_pos++));
138}
139
140static __inline void
141_citrus_memory_stream_ungetc(struct _citrus_memory_stream *ms, int ch)
142{
143
144	if (ch != EOF && ms->ms_pos > 0)
145		ms->ms_pos--;
146}
147
148static __inline int
149_citrus_memory_stream_peek(struct _citrus_memory_stream *ms)
150{
151
152	if (_citrus_memory_stream_iseof(ms))
153		return (EOF);
154	return (_citrus_region_peek8(&ms->ms_region, ms->ms_pos));
155}
156
157static __inline void *
158_citrus_memory_stream_getregion(struct _citrus_memory_stream *ms,
159    struct _citrus_region *r, size_t sz)
160{
161	void *ret;
162
163	if (ms->ms_pos + sz > _citrus_region_size(&ms->ms_region))
164		return (NULL);
165
166	ret = _citrus_region_offset(&ms->ms_region, ms->ms_pos);
167	ms->ms_pos += sz;
168	if (r)
169		_citrus_region_init(r, ret, sz);
170
171	return (ret);
172}
173
174static __inline int
175_citrus_memory_stream_get8(struct _citrus_memory_stream *ms, uint8_t *rval)
176{
177
178	if (ms->ms_pos + 1 > _citrus_region_size(&ms->ms_region))
179		return (-1);
180
181	*rval = _citrus_region_peek8(&ms->ms_region, ms->ms_pos);
182	ms->ms_pos += 2;
183
184	return (0);
185}
186
187static __inline int
188_citrus_memory_stream_get16(struct _citrus_memory_stream *ms, uint16_t *rval)
189{
190
191	if (ms->ms_pos + 2 > _citrus_region_size(&ms->ms_region))
192		return (-1);
193
194	*rval = _citrus_region_peek16(&ms->ms_region, ms->ms_pos);
195	ms->ms_pos += 2;
196
197	return (0);
198}
199
200static __inline int
201_citrus_memory_stream_get32(struct _citrus_memory_stream *ms, uint32_t *rval)
202{
203
204	if (ms->ms_pos + 4 > _citrus_region_size(&ms->ms_region))
205		return (-1);
206
207	*rval = _citrus_region_peek32(&ms->ms_region, ms->ms_pos);
208	ms->ms_pos += 4;
209
210	return (0);
211}
212
213static __inline int
214_citrus_memory_stream_getln_region(struct _citrus_memory_stream *ms,
215    struct _citrus_region *r)
216{
217	const char *ptr;
218	size_t sz;
219
220	ptr = _citrus_memory_stream_getln(ms, &sz);
221	if (ptr)
222		_citrus_region_init(r, __DECONST(void *, ptr), sz);
223
224	return (ptr == NULL);
225}
226
227#endif
228