chars.c revision 1.1.1.8 
1/*	$Vendor-Id: chars.c,v 1.20 2010/06/19 20:46:27 kristaps Exp $ */
2/*
3 * Copyright (c) 2009 Kristaps Dzonsons <kristaps@bsd.lv>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17#ifdef HAVE_CONFIG_H
18#include "config.h"
19#endif
20
21#include <assert.h>
22#include <stdio.h>
23#include <stdlib.h>
24#include <string.h>
25
26#include "mandoc.h"
27#include "chars.h"
28
29#define	PRINT_HI	 126
30#define	PRINT_LO	 32
31
32struct	ln {
33	struct ln	 *next;
34	const char	 *code;
35	const char	 *ascii;
36	const char	 *html;
37	size_t		  codesz;
38	size_t		  asciisz;
39	size_t		  htmlsz;
40	int		  type;
41#define	CHARS_CHAR	 (1 << 0)
42#define	CHARS_STRING	 (1 << 1)
43#define CHARS_BOTH	 (CHARS_CHAR | CHARS_STRING)
44};
45
46#define	LINES_MAX	  370
47
48#define CHAR(w, x, y, z, a, b) \
49	{ NULL, (w), (y), (a), (x), (z), (b), CHARS_CHAR },
50#define STRING(w, x, y, z, a, b) \
51	{ NULL, (w), (y), (a), (x), (z), (b), CHARS_STRING },
52#define BOTH(w, x, y, z, a, b) \
53	{ NULL, (w), (y), (a), (x), (z), (b), CHARS_BOTH },
54
55#define	CHAR_TBL_START	  static struct ln lines[LINES_MAX] = {
56#define	CHAR_TBL_END	  };
57
58#include "chars.in"
59
60struct	tbl {
61	enum chars	  type;
62	struct ln	**htab;
63};
64
65static	inline int	  match(const struct ln *,
66				const char *, size_t, int);
67static	const char	 *find(struct tbl *, const char *,
68				size_t, size_t *, int);
69
70
71void
72chars_free(void *arg)
73{
74	struct tbl	*tab;
75
76	tab = (struct tbl *)arg;
77
78	free(tab->htab);
79	free(tab);
80}
81
82
83void *
84chars_init(enum chars type)
85{
86	struct tbl	 *tab;
87	struct ln	**htab;
88	struct ln	 *pp;
89	int		  i, hash;
90
91	/*
92	 * Constructs a very basic chaining hashtable.  The hash routine
93	 * is simply the integral value of the first character.
94	 * Subsequent entries are chained in the order they're processed
95	 * (they're in-line re-ordered during lookup).
96	 */
97
98	tab = malloc(sizeof(struct tbl));
99	if (NULL == tab) {
100		perror(NULL);
101		exit(EXIT_FAILURE);
102	}
103
104	htab = calloc(PRINT_HI - PRINT_LO + 1, sizeof(struct ln **));
105	if (NULL == htab) {
106		perror(NULL);
107		exit(EXIT_FAILURE);
108	}
109
110	for (i = 0; i < LINES_MAX; i++) {
111		hash = (int)lines[i].code[0] - PRINT_LO;
112
113		if (NULL == (pp = htab[hash])) {
114			htab[hash] = &lines[i];
115			continue;
116		}
117
118		for ( ; pp->next; pp = pp->next)
119			/* Scan ahead. */ ;
120		pp->next = &lines[i];
121	}
122
123	tab->htab = htab;
124	tab->type = type;
125	return(tab);
126}
127
128
129const char *
130chars_a2ascii(void *arg, const char *p, size_t sz, size_t *rsz)
131{
132
133	return(find((struct tbl *)arg, p, sz, rsz, CHARS_CHAR));
134}
135
136
137const char *
138chars_a2res(void *arg, const char *p, size_t sz, size_t *rsz)
139{
140
141	return(find((struct tbl *)arg, p, sz, rsz, CHARS_STRING));
142}
143
144
145static const char *
146find(struct tbl *tab, const char *p, size_t sz, size_t *rsz, int type)
147{
148	struct ln	 *pp, *prev;
149	struct ln	**htab;
150	int		  hash;
151
152	assert(p);
153	assert(sz > 0);
154
155	if (p[0] < PRINT_LO || p[0] > PRINT_HI)
156		return(NULL);
157
158	/*
159	 * Lookup the symbol in the symbol hash.  See ascii2htab for the
160	 * hashtable specs.  This dynamically re-orders the hash chain
161	 * to optimise for repeat hits.
162	 */
163
164	hash = (int)p[0] - PRINT_LO;
165	htab = tab->htab;
166
167	if (NULL == (pp = htab[hash]))
168		return(NULL);
169
170	for (prev = NULL; pp; pp = pp->next) {
171		if ( ! match(pp, p, sz, type)) {
172			prev = pp;
173			continue;
174		}
175
176		if (prev) {
177			prev->next = pp->next;
178			pp->next = htab[hash];
179			htab[hash] = pp;
180		}
181
182		if (CHARS_HTML == tab->type) {
183			*rsz = pp->htmlsz;
184			return(pp->html);
185		}
186		*rsz = pp->asciisz;
187		return(pp->ascii);
188	}
189
190	return(NULL);
191}
192
193
194static inline int
195match(const struct ln *ln, const char *p, size_t sz, int type)
196{
197
198	if ( ! (ln->type & type))
199		return(0);
200	if (ln->codesz != sz)
201		return(0);
202	return(0 == strncmp(ln->code, p, sz));
203}
204