1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1989, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Case Larsen.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <err.h>
36 #include <limits.h>
37 #include <locale.h>
38 #include <stdint.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <unistd.h>
43 #include <wchar.h>
44 #include <wctype.h>
45
46 static int iflag;
47 static const char *tabs[] = { "", "\t", "\t\t" };
48
49 static FILE *file(const char *);
50 static wchar_t *convert(const char *);
51 static void show(FILE *, const char *, const char *, char **, size_t *);
52 static void usage(void);
53
54 int
main(int argc,char * argv[])55 main(int argc, char *argv[])
56 {
57 int comp, read1, read2;
58 int ch, flag1, flag2, flag3;
59 FILE *fp1, *fp2;
60 const char *col1, *col2, *col3;
61 size_t line1len, line2len;
62 char *line1, *line2;
63 ssize_t n1, n2;
64 wchar_t *tline1, *tline2;
65 const char **p;
66
67 (void) setlocale(LC_ALL, "");
68
69 flag1 = flag2 = flag3 = 1;
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 line1len = line2len = 0;
109 line1 = line2 = NULL;
110 n1 = n2 = -1;
111
112 for (read1 = read2 = 1;;) {
113 /* read next line, check for EOF */
114 if (read1) {
115 n1 = getline(&line1, &line1len, fp1);
116 if (n1 < 0 && ferror(fp1))
117 err(1, "%s", argv[0]);
118 if (n1 > 0 && line1[n1 - 1] == '\n')
119 line1[n1 - 1] = '\0';
120
121 }
122 if (read2) {
123 n2 = getline(&line2, &line2len, fp2);
124 if (n2 < 0 && ferror(fp2))
125 err(1, "%s", argv[1]);
126 if (n2 > 0 && line2[n2 - 1] == '\n')
127 line2[n2 - 1] = '\0';
128 }
129
130 /* if one file done, display the rest of the other file */
131 if (n1 < 0) {
132 if (n2 >= 0)
133 show(fp2, argv[1], col2, &line2, &line2len);
134 break;
135 }
136 if (n2 < 0) {
137 if (n1 >= 0)
138 show(fp1, argv[0], col1, &line1, &line1len);
139 break;
140 }
141
142 tline2 = NULL;
143 if ((tline1 = convert(line1)) != NULL)
144 tline2 = convert(line2);
145 if (tline1 == NULL || tline2 == NULL)
146 comp = strcmp(line1, line2);
147 else
148 comp = wcscoll(tline1, tline2);
149 if (tline1 != NULL)
150 free(tline1);
151 if (tline2 != NULL)
152 free(tline2);
153
154 /* lines are the same */
155 if (!comp) {
156 read1 = read2 = 1;
157 if (col3 != NULL)
158 (void)printf("%s%s\n", col3, line1);
159 continue;
160 }
161
162 /* lines are different */
163 if (comp < 0) {
164 read1 = 1;
165 read2 = 0;
166 if (col1 != NULL)
167 (void)printf("%s%s\n", col1, line1);
168 } else {
169 read1 = 0;
170 read2 = 1;
171 if (col2 != NULL)
172 (void)printf("%s%s\n", col2, line2);
173 }
174 }
175 if (ferror(stdout) != 0 || fflush(stdout) != 0)
176 err(1, "stdout");
177 exit(0);
178 }
179
180 static wchar_t *
convert(const char * str)181 convert(const char *str)
182 {
183 size_t n;
184 wchar_t *buf, *p;
185
186 if ((n = mbstowcs(NULL, str, 0)) == (size_t)-1)
187 return (NULL);
188 if (SIZE_MAX / sizeof(*buf) < n + 1)
189 errx(1, "conversion buffer length overflow");
190 if ((buf = malloc((n + 1) * sizeof(*buf))) == NULL)
191 err(1, "malloc");
192 if (mbstowcs(buf, str, n + 1) != n)
193 errx(1, "internal mbstowcs() error");
194
195 if (iflag) {
196 for (p = buf; *p != L'\0'; p++)
197 *p = towlower(*p);
198 }
199
200 return (buf);
201 }
202
203 static void
show(FILE * fp,const char * fn,const char * offset,char ** bufp,size_t * buflenp)204 show(FILE *fp, const char *fn, const char *offset, char **bufp, size_t *buflenp)
205 {
206 ssize_t n;
207
208 do {
209 /* offset is NULL when draining fp, not printing */
210 if (offset != NULL)
211 (void)printf("%s%s\n", offset, *bufp);
212 if ((n = getline(bufp, buflenp, fp)) < 0)
213 break;
214 if (n > 0 && offset != NULL && (*bufp)[n - 1] == '\n')
215 (*bufp)[n - 1] = '\0';
216 } while (1);
217 if (ferror(fp))
218 err(1, "%s", fn);
219 }
220
221 static FILE *
file(const char * name)222 file(const char *name)
223 {
224 FILE *fp;
225
226 if (!strcmp(name, "-"))
227 return (stdin);
228 if ((fp = fopen(name, "r")) == NULL) {
229 err(1, "%s", name);
230 }
231 return (fp);
232 }
233
234 static void
usage(void)235 usage(void)
236 {
237 (void)fprintf(stderr, "usage: comm [-123i] file1 file2\n");
238 exit(1);
239 }
240