1/*	$NetBSD: citrus_memstream.h,v 1.2 2004/12/30 05:01:19 christos Exp $	*/
2
3/*-
4 * Copyright (c)2003 Citrus Project,
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 */
29
30#ifndef _CITRUS_MEMSTREAM_H_
31#define _CITRUS_MEMSTREAM_H_
32
33struct _citrus_memory_stream {
34	struct _citrus_region	ms_region;
35	size_t			ms_pos;
36};
37
38__BEGIN_DECLS
39const char *	_citrus_memory_stream_getln(
40	struct _citrus_memory_stream * __restrict, size_t * __restrict);
41const char *	_citrus_memory_stream_matchline(
42	struct _citrus_memory_stream * __restrict, const char * __restrict,
43	size_t * __restrict, int);
44void *		_citrus_memory_stream_chr(struct _citrus_memory_stream *,
45					  struct _citrus_region *, char);
46void		_citrus_memory_stream_skip_ws(struct _citrus_memory_stream *);
47__END_DECLS
48
49static __inline int
50_citrus_memory_stream_iseof(struct _citrus_memory_stream *ms)
51{
52	return ms->ms_pos >= _citrus_region_size(&ms->ms_region);
53}
54
55static __inline void
56_citrus_memory_stream_bind(struct _citrus_memory_stream * __restrict ms,
57			   const struct _citrus_region * __restrict r)
58{
59	ms->ms_region = *r;
60	ms->ms_pos = 0;
61}
62
63static __inline void
64_citrus_memory_stream_bind_ptr(struct _citrus_memory_stream * __restrict ms,
65			       void *ptr, size_t sz)
66{
67	struct _citrus_region r;
68
69	_citrus_region_init(&r, ptr, sz);
70	_citrus_memory_stream_bind(ms, &r);
71}
72
73static __inline void
74_citrus_memory_stream_rewind(struct _citrus_memory_stream *ms)
75{
76	ms->ms_pos = 0;
77}
78
79static __inline size_t
80_citrus_memory_stream_tell(struct _citrus_memory_stream *ms)
81{
82	return ms->ms_pos;
83}
84
85static __inline size_t
86_citrus_memory_stream_remainder(struct _citrus_memory_stream *ms)
87{
88	size_t sz;
89	sz = _citrus_region_size(&ms->ms_region);
90	if (ms->ms_pos>sz)
91		return 0;
92	return sz-ms->ms_pos;
93}
94
95static __inline int
96_citrus_memory_stream_seek(struct _citrus_memory_stream *ms, size_t pos, int w)
97{
98	size_t sz = _citrus_region_size(&ms->ms_region);
99	switch (w) {
100	case SEEK_SET:
101		if (pos>=sz)
102			return -1;
103		ms->ms_pos = pos;
104		break;
105	case SEEK_CUR:
106		pos += (ssize_t)ms->ms_pos;
107		if (pos>=sz)
108			return -1;
109		ms->ms_pos = pos;
110		break;
111	case SEEK_END:
112		if (sz<pos)
113			return -1;
114		ms->ms_pos = sz - pos;
115		break;
116	}
117	return 0;
118}
119
120static __inline int
121_citrus_memory_stream_getc(struct _citrus_memory_stream *ms)
122{
123	if (_citrus_memory_stream_iseof(ms))
124		return (EOF);
125	return _citrus_region_peek8(&ms->ms_region, ms->ms_pos++);
126}
127
128static __inline void
129_citrus_memory_stream_ungetc(struct _citrus_memory_stream *ms, int ch)
130{
131	if (ch != EOF && ms->ms_pos > 0)
132		ms->ms_pos--;
133}
134
135static __inline int
136_citrus_memory_stream_peek(struct _citrus_memory_stream *ms)
137{
138	if (_citrus_memory_stream_iseof(ms))
139		return (EOF);
140	return _citrus_region_peek8(&ms->ms_region, ms->ms_pos);
141}
142
143static __inline void *
144_citrus_memory_stream_getregion(struct _citrus_memory_stream *ms,
145				struct _citrus_region *r, size_t sz)
146{
147	void *ret;
148
149	if (ms->ms_pos + sz > _citrus_region_size(&ms->ms_region))
150		return NULL;
151
152	ret = _citrus_region_offset(&ms->ms_region, ms->ms_pos);
153	ms->ms_pos += sz;
154	if (r)
155		_citrus_region_init(r, ret, sz);
156
157	return ret;
158}
159
160static __inline int
161_citrus_memory_stream_get8(struct _citrus_memory_stream *ms, uint8_t *rval)
162{
163
164	if (ms->ms_pos + 1 > _citrus_region_size(&ms->ms_region))
165		return -1;
166
167	*rval = _citrus_region_peek8(&ms->ms_region, ms->ms_pos);
168	ms->ms_pos += 2;
169
170	return 0;
171}
172
173static __inline int
174_citrus_memory_stream_get16(struct _citrus_memory_stream *ms, uint16_t *rval)
175{
176
177	if (ms->ms_pos + 2 > _citrus_region_size(&ms->ms_region))
178		return -1;
179
180	*rval = _citrus_region_peek16(&ms->ms_region, ms->ms_pos);
181	ms->ms_pos += 2;
182
183	return 0;
184}
185
186static __inline int
187_citrus_memory_stream_get32(struct _citrus_memory_stream *ms, uint32_t *rval)
188{
189
190	if (ms->ms_pos + 4 > _citrus_region_size(&ms->ms_region))
191		return -1;
192
193	*rval = _citrus_region_peek32(&ms->ms_region, ms->ms_pos);
194	ms->ms_pos += 4;
195
196	return 0;
197}
198
199static __inline int
200_citrus_memory_stream_getln_region(struct _citrus_memory_stream *ms,
201				   struct _citrus_region *r)
202{
203	const char *ptr;
204	size_t sz;
205
206	ptr = _citrus_memory_stream_getln(ms, &sz);
207	if (ptr)
208		_citrus_region_init(r, __UNCONST(ptr), sz);
209
210	return ptr == NULL;
211}
212
213#endif
214