usr.bin/cmp/special.c

   1 /*      $NetBSD: special.c,v 1.14 2011/11/28 10:10:10 wiz 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. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #ifndef lint
  34 #if 0
  35 static char sccsid[] = "@(#)special.c   8.3 (Berkeley) 4/2/94";
  36 #else
  37 __RCSID("$NetBSD: special.c,v 1.14 2011/11/28 10:10:10 wiz Exp $");
  38 #endif
  39 #endif /* not lint */
  40
  41 #include <sys/types.h>
  42
  43 #include <err.h>
  44 #include <stdlib.h>
  45 #include <stdio.h>
  46
  47 #include "extern.h"
  48
  49 void
  50 c_special(int fd1, const char *file1, off_t skip1, int fd2, const char *file2, off_t skip2)
  51 {
  52         int ch1, ch2;
  53         off_t byte, line;
  54         FILE *fp1, *fp2;
  55         int dfound;
  56
  57         dfound = 0;
  58         if ((fp1 = fdopen(fd1, "r")) == NULL)
  59                 err(ERR_EXIT, "%s", file1);
  60         if ((fp2 = fdopen(fd2, "r")) == NULL)
  61                 err(ERR_EXIT, "%s", file2);
  62
  63         for (byte = line = 1; skip1--; byte++) {
  64                 ch1 = getc(fp1);
  65                 if (ch1 == EOF)
  66                         goto eof;
  67                 if (ch1 == '\n')
  68                         line++;
  69         }
  70         for (byte = line = 1; skip2--; byte++) {
  71                 ch2 = getc(fp2);
  72                 if (ch2 == EOF)
  73                         goto eof;
  74                 if (ch2 == '\n')
  75                         line++;
  76         }
  77         dfound = 0;
  78         for (byte = line = 1;; ++byte) {
  79                 ch1 = getc(fp1);
  80                 ch2 = getc(fp2);
  81                 if (ch1 == EOF || ch2 == EOF)
  82                         break;
  83                 if (ch1 != ch2) {
  84                         if (lflag) {
  85                                 dfound = 1;
  86                                 (void)printf("%6lld %3o %3o\n", (long long)byte,
  87                                     ch1, ch2);
  88                         } else
  89                                 diffmsg(file1, file2, byte, line);
  90                                 /* NOTREACHED */
  91                 }
  92                 if (ch1 == '\n')
  93                         ++line;
  94         }
  95
  96  eof:
  97         if (ferror(fp1))
  98                 errmsg(file1, byte, line);
  99         if (ferror(fp2))
 100                 errmsg(file2, byte, line);
 101         if (feof(fp1)) {
 102                 if (!feof(fp2))
 103                         eofmsg(file1, byte, line);
 104         } else
 105                 if (feof(fp2))
 106                         eofmsg(file2, byte, line);
 107         (void)fclose(fp1);
 108         (void)fclose(fp2);
 109         if (dfound)
 110                 exit(DIFF_EXIT);
 111 }