Annotation of src/usr.bin/mandoc/man_hash.c, Revision 1.15
1.15 ! schwarze 1: /* $Id: man_hash.c,v 1.14 2011/04/24 16:22:02 schwarze Exp $ */
1.1 kristaps 2: /*
1.13 schwarze 3: * Copyright (c) 2008, 2009, 2010 Kristaps Dzonsons <kristaps@bsd.lv>
1.1 kristaps 4: *
5: * Permission to use, copy, modify, and distribute this software for any
1.2 schwarze 6: * purpose with or without fee is hereby granted, provided that the above
7: * copyright notice and this permission notice appear in all copies.
1.1 kristaps 8: *
1.2 schwarze 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.
1.1 kristaps 16: */
1.7 schwarze 17: #include <sys/types.h>
18:
1.1 kristaps 19: #include <assert.h>
1.8 schwarze 20: #include <ctype.h>
1.6 schwarze 21: #include <limits.h>
1.1 kristaps 22: #include <stdlib.h>
23: #include <string.h>
24:
1.14 schwarze 25: #include "man.h"
1.12 schwarze 26: #include "mandoc.h"
1.1 kristaps 27: #include "libman.h"
28:
1.15 ! schwarze 29: #define HASH_DEPTH 6
1.8 schwarze 30:
31: #define HASH_ROW(x) do { \
1.15 ! schwarze 32: if (isupper((unsigned char)(x))) \
1.8 schwarze 33: (x) -= 65; \
34: else \
35: (x) -= 97; \
36: (x) *= HASH_DEPTH; \
37: } while (/* CONSTCOND */ 0)
38:
39: /*
40: * Lookup table is indexed first by lower-case first letter (plus one
41: * for the period, which is stored in the last row), then by lower or
42: * uppercase second letter. Buckets correspond to the index of the
43: * macro (the integer value of the enum stored as a char to save a bit
44: * of space).
45: */
1.15 ! schwarze 46: static unsigned char table[26 * HASH_DEPTH];
1.1 kristaps 47:
1.6 schwarze 48: /*
49: * XXX - this hash has global scope, so if intended for use as a library
50: * with multiple callers, it will need re-invocation protection.
51: */
1.1 kristaps 52: void
1.6 schwarze 53: man_hash_init(void)
1.1 kristaps 54: {
55: int i, j, x;
56:
1.6 schwarze 57: memset(table, UCHAR_MAX, sizeof(table));
1.1 kristaps 58:
1.10 schwarze 59: assert(/* LINTED */
60: MAN_MAX < UCHAR_MAX);
1.8 schwarze 61:
1.10 schwarze 62: for (i = 0; i < (int)MAN_MAX; i++) {
1.1 kristaps 63: x = man_macronames[i][0];
64:
1.15 ! schwarze 65: assert(isalpha((unsigned char)x));
1.1 kristaps 66:
1.8 schwarze 67: HASH_ROW(x);
68:
69: for (j = 0; j < HASH_DEPTH; j++)
1.6 schwarze 70: if (UCHAR_MAX == table[x + j]) {
1.15 ! schwarze 71: table[x + j] = (unsigned char)i;
1.1 kristaps 72: break;
73: }
1.8 schwarze 74:
75: assert(j < HASH_DEPTH);
1.1 kristaps 76: }
77: }
78:
1.8 schwarze 79:
80: enum mant
1.6 schwarze 81: man_hash_find(const char *tmp)
1.1 kristaps 82: {
1.8 schwarze 83: int x, y, i;
84: enum mant tok;
1.1 kristaps 85:
1.8 schwarze 86: if ('\0' == (x = tmp[0]))
1.1 kristaps 87: return(MAN_MAX);
1.15 ! schwarze 88: if ( ! (isalpha((unsigned char)x)))
1.1 kristaps 89: return(MAN_MAX);
90:
1.8 schwarze 91: HASH_ROW(x);
1.1 kristaps 92:
1.8 schwarze 93: for (i = 0; i < HASH_DEPTH; i++) {
94: if (UCHAR_MAX == (y = table[x + i]))
1.1 kristaps 95: return(MAN_MAX);
1.8 schwarze 96:
97: tok = (enum mant)y;
1.1 kristaps 98: if (0 == strcmp(tmp, man_macronames[tok]))
99: return(tok);
100: }
101:
102: return(MAN_MAX);
103: }