initial import of NetBSD tree

1 files changed, 220 insertions, 0 deletions

diff --git a/src/lib/libc/string/bm.c b/src/lib/libc/string/bm.c
new file mode 100644
index 0000000000..68eac22ecc
--- /dev/null
+++ b/src/lib/libc/string/bm.c
@@ -0,0 +1,220 @@
+/*-
+ * Copyright (c) 1994
+ *      The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Andrew Hume of AT&T Bell Laboratories.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *      This product includes software developed by the University of
+ *      California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+/* from: static char sccsid[] = "@(#)bm.c       8.7 (Berkeley) 6/21/94"; */
+static char *rcsid = "$Id: bm.c,v 1.1.1.1 1995/10/18 08:42:20 deraadt Exp $";
+#endif /* not lint */
+
+#include <sys/types.h>
+
+#include <bm.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+/* 
+ * XXX
+ * The default frequency table starts at 99 and counts down.  The default
+ * table should probably be oriented toward text, and will necessarily be
+ * locale specific.  This one is for English.  It was derived from the
+ * OSF/1 and 4.4BSD formatted and unformatted manual pages, and about 100Mb
+ * of email and random text.  Change it if you can find something better.
+ */
+static u_char const freq_def[256] = {
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0, 77, 90,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+        99, 28, 42, 27, 16, 14, 20, 51,
+        66, 65, 59, 24, 75, 76, 84, 56,
+        72, 74, 64, 55, 54, 47, 41, 37,
+        44, 61, 70, 43, 23, 53, 49, 22,
+        33, 58, 40, 46, 45, 57, 60, 26,
+        30, 63, 21, 12, 32, 50, 38, 39,
+        34, 11, 48, 67, 62, 35, 15, 29,
+        71, 18,  9, 17, 25, 13, 10, 52,
+        36, 95, 78, 86, 87, 98, 82, 80,
+        88, 94, 19, 68, 89, 83, 93, 96,
+        81,  7, 91, 92, 97, 85, 69, 73,
+        31, 79,  8,  5,  4,  6,  3,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+         0,  0,  0,  0,  0,  0,  0,  0,
+};
+
+bm_pat *
+bm_comp(pb, len, freq)
+        u_char const *pb;
+        size_t len;
+        u_char const *freq;
+{
+        register u_char const *pe, *p;
+        register size_t *d, r;
+        register int j;
+        int sv_errno;
+        bm_pat *pat;
+
+        if (len == 0) {
+                errno = EINVAL;
+                return (NULL);
+        }
+        if ((pat = malloc(sizeof(*pat))) == NULL)
+                return (NULL);
+        pat->pat = NULL;
+        pat->delta = NULL;
+
+        pat->patlen = len;                      /* copy pattern */
+        if ((pat->pat = malloc(pat->patlen)) == NULL)
+                goto mem;
+        memcpy(pat->pat, pb, pat->patlen);
+                                                /* get skip delta */
+        if ((pat->delta = malloc(256 * sizeof(*d))) == NULL)
+                goto mem;
+        for (j = 0, d = pat->delta; j < 256; j++)
+                d[j] = pat->patlen;
+        for (pe = pb + pat->patlen - 1; pb <= pe; pb++)
+                d[*pb] = pe - pb;
+
+        if (freq == NULL)                       /* default freq table */
+                freq = freq_def;
+        r = 0;                                  /* get guard */
+        for (pb = pat->pat, pe = pb + pat->patlen - 1; pb < pe; pb++)
+                if (freq[*pb] < freq[pat->pat[r]])
+                        r = pb - pat->pat;
+        pat->rarec = pat->pat[r];
+        pat->rareoff = r - (pat->patlen - 1);
+
+                                                /* get md2 shift */
+        for (pe = pat->pat + pat->patlen - 1, p = pe - 1; p >= pat->pat; p--)
+                if (*p == *pe)
+                        break;
+
+        /* *p is first leftward reoccurrence of *pe */
+        pat->md2 = pe - p;
+        return (pat);
+
+mem:    sv_errno = errno;
+        bm_free(pat);
+        errno = sv_errno;
+        return (NULL);
+}
+
+void
+bm_free(pat)
+        bm_pat *pat;
+{
+        if (pat->pat != NULL)
+                free(pat->pat);
+        if (pat->delta != NULL)
+                free(pat->delta);
+        free(pat);
+}
+
+u_char *
+bm_exec(pat, base, n)
+        bm_pat *pat;
+        u_char *base;
+        size_t n;
+{
+        register u_char *e, *ep, *p, *q, *s;
+        register size_t *d0, k, md2, n1, ro;
+        register int rc;
+
+        if (n == 0)
+                return (NULL);
+
+        d0 = pat->delta;
+        n1 = pat->patlen - 1;
+        md2 = pat->md2;
+        ro = pat->rareoff;
+        rc = pat->rarec;
+        ep = pat->pat + pat->patlen - 1;
+        s = base + (pat->patlen - 1);
+
+        /* fast loop up to n - 3 * patlen */
+        e = base + n - 3 * pat->patlen;
+        while (s < e) {
+                k = d0[*s];             /* ufast skip loop */
+                while (k) {
+                        k = d0[*(s += k)];
+                        k = d0[*(s += k)];
+                }
+                if (s >= e)
+                        break;
+                if (s[ro] != rc)        /* guard test */
+                        goto mismatch1;
+                                        /* fwd match */
+                for (p = pat->pat, q = s - n1; p < ep;)
+                        if (*q++ != *p++)
+                                goto mismatch1;
+                return (s - n1);
+
+mismatch1:      s += md2;               /* md2 shift */
+        }
+
+        /* slow loop up to end */
+        e = base + n;
+        while (s < e) {
+                s += d0[*s];            /* step */
+                if (s >= e)
+                        break;
+                if (s[ro] != rc)        /* guard test */
+                        goto mismatch2;
+                                        /* fwd match */
+                for (p = pat->pat, q = s - n1; p <= ep;)
+                        if (*q++ != *p++)
+                                goto mismatch2;
+                return (s - n1);
+
+mismatch2:      s += md2;               /* md2 shift */
+        }
+
+        return (NULL);
+}