usr.bin/cmp/special.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   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  * $FreeBSD: head/usr.bin/cmp/special.c 223376 2011-06-21 20:44:06Z delphij $
  32  *
  33  * @(#)special.c        8.3 (Berkeley) 4/2/94
  34  */
  35
  36 #include <sys/types.h>
  37
  38 #include <err.h>
  39 #include <stdlib.h>
  40 #include <stdio.h>
  41
  42 #include "extern.h"
  43
  44 void
  45 c_special(int fd1, const char *file1, off_t skip1,
  46     int fd2, const char *file2, off_t skip2)
  47 {
  48         int ch1, ch2;
  49         off_t byte, line;
  50         FILE *fp1, *fp2;
  51         int dfound;
  52
  53         if ((fp1 = fdopen(fd1, "r")) == NULL)
  54                 err(ERR_EXIT, "%s", file1);
  55         if ((fp2 = fdopen(fd2, "r")) == NULL)
  56                 err(ERR_EXIT, "%s", file2);
  57
  58         dfound = 0;
  59         while (skip1--)
  60                 if (getc(fp1) == EOF)
  61                         goto eof;
  62         while (skip2--)
  63                 if (getc(fp2) == EOF)
  64                         goto eof;
  65
  66         for (byte = line = 1;; ++byte) {
  67                 ch1 = getc(fp1);
  68                 ch2 = getc(fp2);
  69                 if (ch1 == EOF || ch2 == EOF)
  70                         break;
  71                 if (ch1 != ch2) {
  72                         if (xflag) {
  73                                 dfound = 1;
  74                                 printf("%08jx %02x %02x\n",
  75                                     (intmax_t)byte - 1, ch1, ch2);
  76                         } else if (lflag) {
  77                                 dfound = 1;
  78                                 printf("%6jd %3o %3o\n",
  79                                     (intmax_t)byte, ch1, ch2);
  80                         } else {
  81                                 diffmsg(file1, file2, byte, line);
  82                                 /* NOTREACHED */
  83                         }
  84                 }
  85                 if (ch1 == '\n')
  86                         ++line;
  87         }
  88
  89 eof:    if (ferror(fp1))
  90                 err(ERR_EXIT, "%s", file1);
  91         if (ferror(fp2))
  92                 err(ERR_EXIT, "%s", file2);
  93         if (feof(fp1)) {
  94                 if (!feof(fp2))
  95                         eofmsg(file1);
  96         } else
  97                 if (feof(fp2))
  98                         eofmsg(file2);
  99         fclose(fp2);
 100         fclose(fp1);
 101         if (dfound)
 102                 exit(DIFF_EXIT);
 103 }