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-rw-r--r--ltp_framework/lib/pattern.c168
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diff --git a/ltp_framework/lib/pattern.c b/ltp_framework/lib/pattern.c
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+/*
+ * Copyright (c) 2000 Silicon Graphics, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like. Any license provided herein, whether implied or
+ * otherwise, applies only to this software file. Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA 94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/NoticeExplan/
+ */
+#include <string.h>
+#include "pattern.h"
+
+/*
+ * The routines in this module are used to fill/check a data buffer
+ * with/against a known pattern.
+ */
+
+int
+pattern_check(buf, buflen, pat, patlen, patshift)
+char *buf;
+int buflen;
+char *pat;
+int patlen;
+int patshift;
+{
+ int nb, ncmp, nleft;
+ char *cp;
+
+ if (patlen)
+ patshift = patshift % patlen;
+
+ cp = buf;
+ nleft = buflen;
+
+ /*
+ * The following 2 blocks of code are to compare the first patlen
+ * bytes of buf. We need 2 checks if patshift is > 0 since we
+ * must check the last (patlen - patshift) bytes, and then the
+ * first (patshift) bytes.
+ */
+
+ nb = patlen - patshift;
+ if (nleft < nb) {
+ return (memcmp(cp, pat + patshift, nleft) ? -1 : 0);
+ } else {
+ if (memcmp(cp, pat + patshift, nb))
+ return -1;
+
+ nleft -= nb;
+ cp += nb;
+ }
+
+ if (patshift > 0) {
+ nb = patshift;
+ if (nleft < nb) {
+ return (memcmp(cp, pat, nleft) ? -1 : 0);
+ } else {
+ if (memcmp(cp, pat, nb))
+ return -1;
+
+ nleft -= nb;
+ cp += nb;
+ }
+ }
+
+ /*
+ * Now, verify the rest of the buffer using the algorithm described
+ * in the function header.
+ */
+
+ ncmp = cp - buf;
+ while (ncmp < buflen) {
+ nb = (ncmp < nleft) ? ncmp : nleft;
+ if (memcmp(buf, cp, nb))
+ return -1;
+
+ cp += nb;
+ ncmp += nb;
+ nleft -= nb;
+ }
+
+ return 0;
+}
+
+int
+pattern_fill(buf, buflen, pat, patlen, patshift)
+char *buf;
+int buflen;
+char *pat;
+int patlen;
+int patshift;
+{
+ int trans, ncopied, nleft;
+ char *cp;
+
+ if (patlen)
+ patshift = patshift % patlen;
+
+ cp = buf;
+ nleft = buflen;
+
+ /*
+ * The following 2 blocks of code are to fill the first patlen
+ * bytes of buf. We need 2 sections if patshift is > 0 since we
+ * must first copy the last (patlen - patshift) bytes into buf[0]...,
+ * and then the first (patshift) bytes of pattern following them.
+ */
+
+ trans = patlen - patshift;
+ if (nleft < trans) {
+ memcpy(cp, pat + patshift, nleft);
+ return 0;
+ } else {
+ memcpy(cp, pat + patshift, trans);
+ nleft -= trans;
+ cp += trans;
+ }
+
+ if (patshift > 0) {
+ trans = patshift;
+ if (nleft < trans) {
+ memcpy(cp, pat, nleft);
+ return 0;
+ } else {
+ memcpy(cp, pat, trans);
+ nleft -= trans;
+ cp += trans;
+ }
+ }
+
+ /*
+ * Now, fill the rest of the buffer using the algorithm described
+ * in the function header comment.
+ */
+
+ ncopied = cp - buf;
+ while (ncopied < buflen) {
+ trans = (ncopied < nleft) ? ncopied : nleft;
+ memcpy(cp, buf, trans);
+ cp += trans;
+ ncopied += trans;
+ nleft -= trans;
+ }
+
+ return(0);
+} \ No newline at end of file