summaryrefslogtreecommitdiffhomepage
path: root/coreutils/tr.c
blob: 48cdd47bddfe5503c48e18ea5a6870cf3c694c3b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
/* vi: set sw=4 ts=4: */
/*
 * Mini tr implementation for busybox
 *
 * Copyright (c) Michiel Huisjes
 *
 * This version of tr is adapted from Minix tr and was modified 
 * by Erik Andersen <andersee@debian.org> to be used in busybox.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 * 
 * Original copyright notice is retained at the end of this file.
 */

#include "internal.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#define BB_DECLARE_EXTERN
#define bb_need_write_error
#include "messages.c"

const char *tr_usage="tr [-cds] STRING1 [STRING2]\n"
#ifndef BB_FEATURE_TRIVIAL_HELP
	"\nTranslate, squeeze, and/or delete characters from\n"
	"standard input, writing to standard output.\n\n"
	"Options:\n"
	"\t-c\ttake complement of STRING1\n"
	"\t-d\tdelete input characters coded STRING1\n"
	"\t-s\tsqueeze multiple output characters of STRING2 into one character\n"
#endif
;



#ifdef TRUE
#undef TRUE
#undef FALSE
#define TRUE	1
#define FALSE	0
#endif

#define ASCII		0377

/* some glabals shared across this file */
static char com_fl, del_fl, sq_fl;
static unsigned char output[BUFSIZ], input[BUFSIZ];
static unsigned char vector[ASCII + 1];
static char invec[ASCII + 1], outvec[ASCII + 1];
static short in_index, out_index;


static void convert()
{
	short read_chars = 0;
	short c, coded;
	short last = -1;

	for (;;) {
		if (in_index == read_chars) {
			if ((read_chars = read(0, (char *) input, BUFSIZ)) <= 0) {
				if (write(1, (char *) output, out_index) != out_index)
					write(2, write_error, strlen(write_error));
				exit(0);
			}
			in_index = 0;
		}
		c = input[in_index++];
		coded = vector[c];
		if (del_fl && invec[c])
			continue;
		if (sq_fl && last == coded && outvec[coded])
			continue;
		output[out_index++] = last = coded;
		if (out_index == BUFSIZ) {
			if (write(1, (char *) output, out_index) != out_index) {
				write(2, write_error, strlen(write_error));
				exit(1);
			}
			out_index = 0;
		}
	}

	/* NOTREACHED */
}

static void map(register unsigned char *string1, register unsigned char *string2)
{
	unsigned char last = '0';

	while (*string1) {
		if (*string2 == '\0')
			vector[*string1] = last;
		else
			vector[*string1] = last = *string2++;
		string1++;
	}
}

static void expand(char *arg, register unsigned char *buffer)
{
	int i, ac;

	while (*arg) {
		if (*arg == '\\') {
			arg++;
			*buffer++ = process_escape_sequence(&arg);
		} else if (*arg == '[') {
			arg++;
			i = *arg++;
			if (*arg++ != '-') {
				*buffer++ = '[';
				arg -= 2;
				continue;
			}
			ac = *arg++;
			while (i <= ac)
				*buffer++ = i++;
			arg++;				/* Skip ']' */
		} else
			*buffer++ = *arg++;
	}
}

static void complement(unsigned char *buffer)
{
	register unsigned char *ptr;
	register short i, index;
	unsigned char conv[ASCII + 2];

	index = 0;
	for (i = 1; i <= ASCII; i++) {
		for (ptr = buffer; *ptr; ptr++)
			if (*ptr == i)
				break;
		if (*ptr == '\0')
			conv[index++] = i & ASCII;
	}
	conv[index] = '\0';
	strcpy((char *) buffer, (char *) conv);
}

extern int tr_main(int argc, char **argv)
{
	register unsigned char *ptr;
	int index = 1;
	short i;

	if (argc > 1 && argv[index][0] == '-') {
		for (ptr = (unsigned char *) &argv[index][1]; *ptr; ptr++) {
			switch (*ptr) {
			case 'c':
				com_fl = TRUE;
				break;
			case 'd':
				del_fl = TRUE;
				break;
			case 's':
				sq_fl = TRUE;
				break;
			default:
				usage(tr_usage);
			}
		}
		index++;
	}
	for (i = 0; i <= ASCII; i++) {
		vector[i] = i;
		invec[i] = outvec[i] = FALSE;
	}

	if (argv[index] != NULL) {
		expand(argv[index++], input);
		if (com_fl)
			complement(input);
		if (argv[index] != NULL)
			expand(argv[index], output);
		if (argv[index] != NULL)
			map(input, output);
		for (ptr = input; *ptr; ptr++)
			invec[*ptr] = TRUE;
		for (ptr = output; *ptr; ptr++)
			outvec[*ptr] = TRUE;
	}
	convert();
	return (0);
}

/*
 * Copyright (c) 1987,1997, Prentice Hall
 * All rights reserved.
 * 
 * Redistribution and use of the MINIX operating system in source and
 * binary forms, with or without modification, are permitted provided
 * that the following conditions are met:
 * 
 * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * 
 * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following
 * disclaimer in the documentation and/or other materials provided
 * with the distribution.
 * 
 * Neither the name of Prentice Hall nor the names of the software
 * authors or contributors may be used to endorse or promote
 * products derived from this software without specific prior
 * written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS, AUTHORS, AND
 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL PRENTICE HALL OR ANY AUTHORS OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */