1 /* $Id: chars.c,v 1.17 2010/03/23 13:25:01 kristaps Exp $ */
3 * Copyright (c) 2009 Kristaps Dzonsons <kristaps@kth.se>
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.
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.
36 #define CHARS_CHAR (1 << 0)
37 #define CHARS_STRING (1 << 1)
38 #define CHARS_BOTH (CHARS_CHAR | CHARS_STRING)
43 #define CHAR(w, x, y, z, a, b) \
44 { NULL, (w), (y), (a), (x), (z), (b), CHARS_CHAR },
45 #define STRING(w, x, y, z, a, b) \
46 { NULL, (w), (y), (a), (x), (z), (b), CHARS_STRING },
47 #define BOTH(w, x, y, z, a, b) \
48 { NULL, (w), (y), (a), (x), (z), (b), CHARS_BOTH },
50 #define CHAR_TBL_START static struct ln lines[LINES_MAX] = {
51 #define CHAR_TBL_END };
60 static inline int match(const struct ln *,
61 const char *, size_t, int);
62 static const char *find(struct tbl *, const char *,
63 size_t, size_t *, int);
71 tab = (struct tbl *)arg;
79 chars_init(enum chars type)
87 * Constructs a very basic chaining hashtable. The hash routine
88 * is simply the integral value of the first character.
89 * Subsequent entries are chained in the order they're processed
90 * (they're in-line re-ordered during lookup).
93 tab = malloc(sizeof(struct tbl));
99 htab = calloc(PRINT_HI - PRINT_LO + 1, sizeof(struct ln **));
105 for (i = 0; i < LINES_MAX; i++) {
106 hash = (int)lines[i].code[0] - PRINT_LO;
108 if (NULL == (pp = htab[hash])) {
109 htab[hash] = &lines[i];
113 for ( ; pp->next; pp = pp->next)
115 pp->next = &lines[i];
125 chars_a2ascii(void *arg, const char *p, size_t sz, size_t *rsz)
128 return(find((struct tbl *)arg, p, sz, rsz, CHARS_CHAR));
133 chars_a2res(void *arg, const char *p, size_t sz, size_t *rsz)
136 return(find((struct tbl *)arg, p, sz, rsz, CHARS_STRING));
141 find(struct tbl *tab, const char *p, size_t sz, size_t *rsz, int type)
143 struct ln *pp, *prev;
150 if (p[0] < PRINT_LO || p[0] > PRINT_HI)
154 * Lookup the symbol in the symbol hash. See ascii2htab for the
155 * hashtable specs. This dynamically re-orders the hash chain
156 * to optimise for repeat hits.
159 hash = (int)p[0] - PRINT_LO;
162 if (NULL == (pp = htab[hash]))
165 for (prev = NULL; pp; pp = pp->next) {
166 if ( ! match(pp, p, sz, type)) {
172 prev->next = pp->next;
173 pp->next = htab[hash];
177 if (CHARS_HTML == tab->type) {
190 match(const struct ln *ln, const char *p, size_t sz, int type)
193 if ( ! (ln->type & type))
195 if (ln->codesz != sz)
197 return(0 == strncmp(ln->code, p, sz));