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