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regular.c revision 1.9 
      1 /*	$NetBSD: regular.c,v 1.9 2000/07/18 10:23:43 jdolecek Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1991, 1993, 1994
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #include <sys/cdefs.h>
     37 #ifndef lint
     38 #if 0
     39 static char sccsid[] = "@(#)regular.c	8.3 (Berkeley) 4/2/94";
     40 #else
     41 __RCSID("$NetBSD: regular.c,v 1.9 2000/07/18 10:23:43 jdolecek Exp $");
     42 #endif
     43 #endif /* not lint */
     44 
     45 #include <sys/param.h>
     46 #include <sys/mman.h>
     47 #include <sys/stat.h>
     48 
     49 #include <err.h>
     50 #include <limits.h>
     51 #include <stdlib.h>
     52 #include <stdio.h>
     53 #include <string.h>
     54 
     55 #include "extern.h"
     56 
     57 void
     58 c_regular(fd1, file1, skip1, len1, fd2, file2, skip2, len2)
     59 	int fd1, fd2;
     60 	char *file1, *file2;
     61 	off_t skip1, len1, skip2, len2;
     62 {
     63 	u_char ch, *p1, *p2;
     64 	off_t byte, length, line;
     65 	int dfound;
     66 
     67 	if (sflag && len1 != len2)
     68 		exit(1);
     69 
     70 	if (skip1 > len1)
     71 		eofmsg(file1);
     72 	len1 -= skip1;
     73 	if (skip2 > len2)
     74 		eofmsg(file2);
     75 	len2 -= skip2;
     76 
     77 	length = MIN(len1, len2);
     78 	if (length > SIZE_T_MAX) {
     79 mmap_failed:
     80 		c_special(fd1, file1, skip1, fd2, file2, skip2);
     81 		return;
     82 	}
     83 
     84 	if ((p1 = (u_char *)mmap(NULL, (size_t)length,
     85 	    PROT_READ, MAP_FILE, fd1, skip1)) == MAP_FAILED)
     86 		goto mmap_failed;
     87 	(void)madvise(p1, (size_t)length, MADV_SEQUENTIAL);
     88 
     89 	if ((p2 = (u_char *)mmap(NULL, (size_t)length,
     90 	    PROT_READ, MAP_FILE, fd2, skip2)) == MAP_FAILED) {
     91 		munmap(p1, (size_t) length);
     92 		goto mmap_failed;
     93 	}
     94 	(void)madvise(p2, (size_t)length, MADV_SEQUENTIAL);
     95 
     96 	dfound = 0;
     97 	for (byte = line = 1; length--; ++p1, ++p2, ++byte) {
     98 		if ((ch = *p1) != *p2) {
     99 			if (lflag) {
    100 				dfound = 1;
    101 				(void)printf("%6qd %3o %3o\n", (long long)byte,
    102 				    ch, *p2);
    103 			} else
    104 				diffmsg(file1, file2, byte, line);
    105 				/* NOTREACHED */
    106 		}
    107 		if (ch == '\n')
    108 			++line;
    109 	}
    110 
    111 	if (len1 != len2)
    112 		eofmsg (len1 > len2 ? file2 : file1);
    113 	if (dfound)
    114 		exit(DIFF_EXIT);
    115 }
    116