diff options
Diffstat (limited to 'usr/src/cmd/mandoc/man_hash.c')
-rw-r--r-- | usr/src/cmd/mandoc/man_hash.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/usr/src/cmd/mandoc/man_hash.c b/usr/src/cmd/mandoc/man_hash.c new file mode 100644 index 0000000000..86c5c40a19 --- /dev/null +++ b/usr/src/cmd/mandoc/man_hash.c @@ -0,0 +1,107 @@ +/* $Id: man_hash.c,v 1.25 2011/07/24 18:15:14 kristaps Exp $ */ +/* + * Copyright (c) 2008, 2009, 2010 Kristaps Dzonsons <kristaps@bsd.lv> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <sys/types.h> + +#include <assert.h> +#include <ctype.h> +#include <limits.h> +#include <stdlib.h> +#include <string.h> + +#include "man.h" +#include "mandoc.h" +#include "libman.h" + +#define HASH_DEPTH 6 + +#define HASH_ROW(x) do { \ + if (isupper((unsigned char)(x))) \ + (x) -= 65; \ + else \ + (x) -= 97; \ + (x) *= HASH_DEPTH; \ + } while (/* CONSTCOND */ 0) + +/* + * Lookup table is indexed first by lower-case first letter (plus one + * for the period, which is stored in the last row), then by lower or + * uppercase second letter. Buckets correspond to the index of the + * macro (the integer value of the enum stored as a char to save a bit + * of space). + */ +static unsigned char table[26 * HASH_DEPTH]; + +/* + * XXX - this hash has global scope, so if intended for use as a library + * with multiple callers, it will need re-invocation protection. + */ +void +man_hash_init(void) +{ + int i, j, x; + + memset(table, UCHAR_MAX, sizeof(table)); + + assert(/* LINTED */ + MAN_MAX < UCHAR_MAX); + + for (i = 0; i < (int)MAN_MAX; i++) { + x = man_macronames[i][0]; + + assert(isalpha((unsigned char)x)); + + HASH_ROW(x); + + for (j = 0; j < HASH_DEPTH; j++) + if (UCHAR_MAX == table[x + j]) { + table[x + j] = (unsigned char)i; + break; + } + + assert(j < HASH_DEPTH); + } +} + + +enum mant +man_hash_find(const char *tmp) +{ + int x, y, i; + enum mant tok; + + if ('\0' == (x = tmp[0])) + return(MAN_MAX); + if ( ! (isalpha((unsigned char)x))) + return(MAN_MAX); + + HASH_ROW(x); + + for (i = 0; i < HASH_DEPTH; i++) { + if (UCHAR_MAX == (y = table[x + i])) + return(MAN_MAX); + + tok = (enum mant)y; + if (0 == strcmp(tmp, man_macronames[tok])) + return(tok); + } + + return(MAN_MAX); +} |