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comparison code/cut.c__4.3bsd-reno.1990-06-25 @ 14:21ad1c1548c4

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Code ausgewaehlter Implementierungen eingefuegt Das Datum entspricht dem Dateiaenderungsdatum.
author markus schnalke <meillo@marmaro.de>
date Tue, 12 May 2015 06:46:59 +0200
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13:bf5e41260f89 14:21ad1c1548c4
1 /*
2 * Copyright (c) 1989 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Adam S. Moskowitz of Menlo Consulting and Marciano Pitargue.
7 *
8 * Redistribution and use in source and binary forms are permitted provided
9 * that: (1) source distributions retain this entire copyright notice and
10 * comment, and (2) distributions including binaries display the following
11 * acknowledgement: ``This product includes software developed by the
12 * University of California, Berkeley and its contributors'' in the
13 * documentation or other materials provided with the distribution and in
14 * all advertising materials mentioning features or use of this software.
15 * Neither the name of the University nor the names of its contributors may
16 * be used to endorse or promote products derived from this software without
17 * specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
19 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
20 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
21 */
22
23 #ifndef lint
24 char copyright[] =
25 "@(#) Copyright (c) 1989 The Regents of the University of California.\n\
26 All rights reserved.\n";
27 #endif /* not lint */
28
29 #ifndef lint
30 static char sccsid[] = "@(#)cut.c 5.3 (Berkeley) 6/24/90";
31 #endif /* not lint */
32
33 #include <limits.h>
34 #include <stdio.h>
35 #include <ctype.h>
36
37 int cflag;
38 char dchar;
39 int dflag;
40 int fflag;
41 int sflag;
42
43 main(argc, argv)
44 int argc;
45 char **argv;
46 {
47 extern char *optarg;
48 extern int errno, optind;
49 FILE *fp;
50 int ch, (*fcn)(), c_cut(), f_cut();
51 char *strerror();
52
53 dchar = '\t'; /* default delimiter is \t */
54
55 while ((ch = getopt(argc, argv, "c:d:f:s")) != EOF)
56 switch(ch) {
57 case 'c':
58 fcn = c_cut;
59 get_list(optarg);
60 cflag = 1;
61 break;
62 case 'd':
63 dchar = *optarg;
64 dflag = 1;
65 break;
66 case 'f':
67 get_list(optarg);
68 fcn = f_cut;
69 fflag = 1;
70 break;
71 case 's':
72 sflag = 1;
73 break;
74 case '?':
75 default:
76 usage();
77 }
78 argc -= optind;
79 argv += optind;
80
81 if (fflag) {
82 if (cflag)
83 usage();
84 } else if (!cflag || dflag || sflag)
85 usage();
86
87 if (*argv)
88 for (; *argv; ++argv) {
89 if (!(fp = fopen(*argv, "r"))) {
90 (void)fprintf(stderr,
91 "cut: %s: %s\n", *argv, strerror(errno));
92 exit(1);
93 }
94 fcn(fp, *argv);
95 }
96 else
97 fcn(stdin, "stdin");
98 exit(0);
99 }
100
101 int autostart, autostop, maxval;
102
103 char positions[_BSD_LINE_MAX + 1];
104
105 get_list(list)
106 char *list;
107 {
108 register char *pos;
109 register int setautostart, start, stop;
110 char *p, *strtok();
111
112 /*
113 * set a byte in the positions array to indicate if a field or
114 * column is to be selected; use +1, it's 1-based, not 0-based.
115 * This parser is less restrictive than the Draft 9 POSIX spec.
116 * POSIX doesn't allow lists that aren't in increasing order or
117 * overlapping lists. We also handle "-3-5" although there's no
118 * real reason too.
119 */
120 for (; p = strtok(list, ", \t"); list = NULL) {
121 setautostart = start = stop = 0;
122 if (*p == '-') {
123 ++p;
124 setautostart = 1;
125 }
126 if (isdigit(*p)) {
127 start = stop = strtol(p, &p, 10);
128 if (setautostart && start > autostart)
129 autostart = start;
130 }
131 if (*p == '-') {
132 if (isdigit(p[1]))
133 stop = strtol(p + 1, &p, 10);
134 if (*p == '-') {
135 ++p;
136 if (!autostop || autostop > stop)
137 autostop = stop;
138 }
139 }
140 if (*p)
141 badlist("illegal list value");
142 if (!stop || !start)
143 badlist("values may not include zero");
144 if (stop > _BSD_LINE_MAX) {
145 /* positions used rather than allocate a new buffer */
146 (void)sprintf(positions, "%d too large (max %d)",
147 stop, _BSD_LINE_MAX);
148 badlist(positions);
149 }
150 if (maxval < stop)
151 maxval = stop;
152 for (pos = positions + start; start++ <= stop; *pos++ = 1);
153 }
154
155 /* overlapping ranges */
156 if (autostop && maxval > autostop)
157 maxval = autostop;
158
159 /* set autostart */
160 if (autostart)
161 memset(positions + 1, '1', autostart);
162 }
163
164 /* ARGSUSED */
165 c_cut(fp, fname)
166 FILE *fp;
167 char *fname;
168 {
169 register int ch, col;
170 register char *pos;
171
172 for (;;) {
173 pos = positions + 1;
174 for (col = maxval; col; --col) {
175 if ((ch = getc(fp)) == EOF)
176 return;
177 if (ch == '\n')
178 break;
179 if (*pos++)
180 putchar(ch);
181 }
182 if (ch != '\n')
183 if (autostop)
184 while ((ch = getc(fp)) != EOF && ch != '\n')
185 putchar(ch);
186 else
187 while ((ch = getc(fp)) != EOF && ch != '\n');
188 putchar('\n');
189 }
190 }
191
192 f_cut(fp, fname)
193 FILE *fp;
194 char *fname;
195 {
196 register int ch, field, isdelim;
197 register char *pos, *p, sep;
198 int output;
199 char lbuf[_BSD_LINE_MAX + 1];
200
201 for (sep = dchar, output = 0; fgets(lbuf, sizeof(lbuf), fp);) {
202 for (isdelim = 0, p = lbuf;; ++p) {
203 if (!(ch = *p)) {
204 (void)fprintf(stderr,
205 "cut: %s: line too long.\n", fname);
206 exit(1);
207 }
208 /* this should work if newline is delimiter */
209 if (ch == sep)
210 isdelim = 1;
211 if (ch == '\n') {
212 if (!isdelim && !sflag)
213 (void)printf("%s", lbuf);
214 break;
215 }
216 }
217 if (!isdelim)
218 continue;
219
220 pos = positions + 1;
221 for (field = maxval, p = lbuf; field; --field, ++pos) {
222 if (*pos) {
223 if (output++)
224 putchar(sep);
225 while ((ch = *p++) != '\n' && ch != sep)
226 putchar(ch);
227 } else
228 while ((ch = *p++) != '\n' && ch != sep);
229 if (ch == '\n')
230 break;
231 }
232 if (ch != '\n')
233 if (autostop) {
234 if (output)
235 putchar(sep);
236 for (; (ch = *p) != '\n'; ++p)
237 putchar(ch);
238 } else
239 for (; (ch = *p) != '\n'; ++p);
240 putchar('\n');
241 }
242 }
243
244 badlist(msg)
245 char *msg;
246 {
247 (void)fprintf(stderr, "cut: [-cf] list: %s.\n", msg);
248 exit(1);
249 }
250
251 usage()
252 {
253 (void)fprintf(stderr,
254 "usage:\tcut -c list [file1 ...]\n\tcut -f list [-s] [-d delim] [file ...]\n");
255 exit(1);
256 }