usr.bin/comm/comm.c

   1 /*
   2  * Copyright (c) 1989, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * Case Larsen.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the University nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  * @(#) Copyright (c) 1989, 1993, 1994 The Regents of the University of California.  All rights reserved.
  33  * @(#)comm.c   8.4 (Berkeley) 5/4/95
  34  * $FreeBSD: src/usr.bin/comm/comm.c,v 1.11.2.3 2002/07/11 00:46:37 tjr Exp $
  35  * $DragonFly: src/usr.bin/comm/comm.c,v 1.3 2003/10/02 17:42:27 hmp Exp $
  36  */
  37
  38 #include <ctype.h>
  39 #include <err.h>
  40 #include <limits.h>
  41 #include <locale.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45 #include <unistd.h>
  46
  47 #define MAXLINELEN      (LINE_MAX + 1)
  48
  49 const char *tabs[] = { "", "\t", "\t\t" };
  50
  51 FILE   *file(char *);
  52 void    show(FILE *, const char *, char *);
  53 int     stricoll(char *, char *);
  54 static void     usage(void);
  55
  56 int
  57 main(int argc, char **argv)
  58 {
  59         int comp, file1done = 0, file2done = 0, read1, read2;
  60         int ch, flag1, flag2, flag3, iflag;
  61         FILE *fp1, *fp2;
  62         const char *col1, *col2, *col3;
  63         char line1[MAXLINELEN], line2[MAXLINELEN];
  64         const char **p;
  65
  66         flag1 = flag2 = flag3 = 1;
  67         iflag = 0;
  68
  69         (void) setlocale(LC_ALL, "");
  70
  71         while ((ch = getopt(argc, argv, "123i")) != -1)
  72                 switch(ch) {
  73                 case '1':
  74                         flag1 = 0;
  75                         break;
  76                 case '2':
  77                         flag2 = 0;
  78                         break;
  79                 case '3':
  80                         flag3 = 0;
  81                         break;
  82                 case 'i':
  83                         iflag = 1;
  84                         break;
  85                 case '?':
  86                 default:
  87                         usage();
  88                 }
  89         argc -= optind;
  90         argv += optind;
  91
  92         if (argc != 2)
  93                 usage();
  94
  95         fp1 = file(argv[0]);
  96         fp2 = file(argv[1]);
  97
  98         /* for each column printed, add another tab offset */
  99         p = tabs;
 100         col1 = col2 = col3 = NULL;
 101         if (flag1)
 102                 col1 = *p++;
 103         if (flag2)
 104                 col2 = *p++;
 105         if (flag3)
 106                 col3 = *p;
 107
 108         for (read1 = read2 = 1;;) {
 109                 /* read next line, check for EOF */
 110                 if (read1)
 111                         file1done = !fgets(line1, MAXLINELEN, fp1);
 112                 if (read2)
 113                         file2done = !fgets(line2, MAXLINELEN, fp2);
 114
 115                 /* if one file done, display the rest of the other file */
 116                 if (file1done) {
 117                         if (!file2done && col2)
 118                                 show(fp2, col2, line2);
 119                         break;
 120                 }
 121                 if (file2done) {
 122                         if (!file1done && col1)
 123                                 show(fp1, col1, line1);
 124                         break;
 125                 }
 126
 127                 /* lines are the same */
 128                 if(iflag)
 129                         comp = stricoll(line1, line2);
 130                 else
 131                         comp = strcoll(line1, line2);
 132
 133                 if (!comp) {
 134                         read1 = read2 = 1;
 135                         if (col3)
 136                                 (void)printf("%s%s", col3, line1);
 137                         continue;
 138                 }
 139
 140                 /* lines are different */
 141                 if (comp < 0) {
 142                         read1 = 1;
 143                         read2 = 0;
 144                         if (col1)
 145                                 (void)printf("%s%s", col1, line1);
 146                 } else {
 147                         read1 = 0;
 148                         read2 = 1;
 149                         if (col2)
 150                                 (void)printf("%s%s", col2, line2);
 151                 }
 152         }
 153         exit(0);
 154 }
 155
 156 void
 157 show(FILE *fp, const char *offset, char *buf)
 158 {
 159
 160         do {
 161                 (void)printf("%s%s", offset, buf);
 162         } while (fgets(buf, MAXLINELEN, fp));
 163 }
 164
 165 FILE *
 166 file(char *name)
 167 {
 168         FILE *fp;
 169
 170         if (!strcmp(name, "-"))
 171                 return (stdin);
 172         if ((fp = fopen(name, "r")) == NULL) {
 173                 err(1, "%s", name);
 174         }
 175         return (fp);
 176 }
 177
 178 static void
 179 usage(void)
 180 {
 181         (void)fprintf(stderr, "usage: comm [-123i] file1 file2\n");
 182         exit(1);
 183 }
 184
 185 int
 186 stricoll(char *s1, char *s2)
 187 {
 188         char *p, line1[MAXLINELEN], line2[MAXLINELEN];
 189
 190         for (p = line1; *s1; s1++)
 191                 *p++ = tolower((unsigned char)*s1);
 192         *p = '\0';
 193         for (p = line2; *s2; s2++)
 194                 *p++ = tolower((unsigned char)*s2);
 195         *p = '\0';
 196         return strcoll(line1, line2);
 197 }