sync to OpenBSD:

[mandoc.git] / man_hash.c

diff --git a/man_hash.c b/man_hash.c
index a6357af2651dacdfd0dd338e8e66c6b09805782c..6524f36e4d29ee1e9793245a13c0e84af163371f 100644 (file)
--- a/man_hash.c
+++ b/man_hash.c
@@ -1,6 +1,6 @@
-/*     $Id: man_hash.c,v 1.7 2009/04/12 19:45:26 kristaps Exp $ */
+/*     $Id: man_hash.c,v 1.23 2010/07/31 23:52:58 schwarze Exp $ */
 /*
- * Copyright (c) 2008, 2009 Kristaps Dzonsons <kristaps@openbsd.org>
+ * 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
@@ -14,78 +14,93 @@
  * 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 "mandoc.h"
 #include "libman.h"
 
+#define        HASH_DEPTH       6
 
-/* ARGUSED */
-void
-man_hash_free(void *htab)
-{
-
-       free(htab);
-}
+#define        HASH_ROW(x) do { \
+               if (isupper((u_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 u_char           table[26 * HASH_DEPTH];
 
-/* ARGUSED */
-void *
-man_hash_alloc(void)
+/*
+ * 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             *htab;
        int              i, j, x;
 
-       htab = calloc(26 * 5, sizeof(int));
-       if (NULL == htab)
-               return(NULL);
+       memset(table, UCHAR_MAX, sizeof(table));
+
+       assert(/* LINTED */ 
+                       MAN_MAX < UCHAR_MAX);
 
-       for (i = 1; i < MAN_MAX; i++) {
+       for (i = 0; i < (int)MAN_MAX; i++) {
                x = man_macronames[i][0];
 
-               assert((x >= 65 && x <= 90) ||
-                               (x >= 97 && x <= 122));
+               assert(isalpha((u_char)x));
 
-               x -= (x <= 90) ? 65 : 97;
-               x *= 5;
+               HASH_ROW(x);
 
-               for (j = 0; j < 5; j++)
-                       if (0 == htab[x + j]) {
-                               htab[x + j] = i;
+               for (j = 0; j < HASH_DEPTH; j++)
+                       if (UCHAR_MAX == table[x + j]) {
+                               table[x + j] = (u_char)i;
                                break;
                        }
 
-               assert(j < 5);
+               assert(j < HASH_DEPTH);
        }
-
-       return((void *)htab);
 }
 
 
-int
-man_hash_find(const void *arg, const char *tmp)
+enum mant
+man_hash_find(const char *tmp)
 {
-       int              x, i, tok;
-       const int       *htab;
-
-       htab = (const int *)arg;
+       int              x, y, i;
+       enum mant        tok;
 
-       if (0 == (x = tmp[0]))
+       if ('\0' == (x = tmp[0]))
                return(MAN_MAX);
-       if ( ! ((x >= 65 && x <= 90) || (x >= 97 && x <= 122)))
+       if ( ! (isalpha((u_char)x)))
                return(MAN_MAX);
 
-       x -= (x <= 90) ? 65 : 97;
-       x *= 5;
+       HASH_ROW(x);
 
-       for (i = 0; i < 5; i++) {
-               if (0 == (tok = htab[x + i]))
+       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);
 }
-