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Diffstat (limited to 'usr/src/cmd/mandoc/man_hash.c')
-rw-r--r--usr/src/cmd/mandoc/man_hash.c107
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
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+++ 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);
+}