busybox/coreutils/tr.c
2001-05-24 21:31:09 +00:00

239 lines
6.4 KiB
C

/* 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 <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include "busybox.h"
static const int ASCII = 0377;
/* some "globals" shared across this file */
static char com_fl, del_fl, sq_fl;
static short in_index, out_index;
/* these last are pointers to static buffers declared in tr_main */
static unsigned char *poutput, *pinput;
static unsigned char *pvector;
static char *pinvec, *poutvec;
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 *) pinput, BUFSIZ)) <= 0) {
if (write(1, (char *) poutput, out_index) != out_index)
write(2, write_error, strlen(write_error));
exit(0);
}
in_index = 0;
}
c = pinput[in_index++];
coded = pvector[c];
if (del_fl && pinvec[c])
continue;
if (sq_fl && last == coded && (pinvec[c] || poutvec[coded]))
continue;
poutput[out_index++] = last = coded;
if (out_index == BUFSIZ) {
if (write(1, (char *) poutput, out_index) != out_index) {
write(2, write_error, strlen(write_error));
exit(1);
}
out_index = 0;
}
}
/* NOTREACHED */
}
static void map(register unsigned char *string1, unsigned int string1_len,
register unsigned char *string2, unsigned int string2_len)
{
unsigned char last = '0';
unsigned int i, j;
for (j = 0, i = 0; i < string1_len; i++) {
if (string2_len <= j)
pvector[string1[i]] = last;
else
pvector[string1[i]] = last = string2[j++];
}
}
/* supported constructs:
* Ranges, e.g., [0-9] ==> 0123456789
* Escapes, e.g., \a ==> Control-G
*/
static unsigned int expand(const char *arg, register unsigned char *buffer)
{
unsigned char *buffer_start = 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 the assumed ']' */
} else
*buffer++ = *arg++;
}
return (buffer - buffer_start);
}
static int complement(unsigned char *buffer, int buffer_len)
{
register short i, j, ix;
char conv[ASCII + 2];
ix = 0;
for (i = 0; i <= ASCII; i++) {
for (j = 0; j < buffer_len; j++)
if (buffer[j] == i)
break;
if (j == buffer_len)
conv[ix++] = i & ASCII;
}
memcpy(buffer, conv, ix);
return ix;
}
extern int tr_main(int argc, char **argv)
{
register unsigned char *ptr;
int output_length=0, input_length;
int idx = 1;
int i;
RESERVE_BB_BUFFER(output, BUFSIZ);
RESERVE_BB_BUFFER(input, BUFSIZ);
RESERVE_BB_UBUFFER(vector, ASCII+1);
RESERVE_BB_BUFFER(invec, ASCII+1);
RESERVE_BB_BUFFER(outvec, ASCII+1);
/* ... but make them available globally */
poutput = output;
pinput = input;
pvector = vector;
pinvec = invec;
poutvec = outvec;
if (argc > 1 && argv[idx][0] == '-') {
for (ptr = (unsigned char *) &argv[idx][1]; *ptr; ptr++) {
switch (*ptr) {
case 'c':
com_fl = TRUE;
break;
case 'd':
del_fl = TRUE;
break;
case 's':
sq_fl = TRUE;
break;
default:
show_usage();
}
}
idx++;
}
for (i = 0; i <= ASCII; i++) {
vector[i] = i;
invec[i] = outvec[i] = FALSE;
}
if (argv[idx] != NULL) {
input_length = expand(argv[idx++], input);
if (com_fl)
input_length = complement(input, input_length);
if (argv[idx] != NULL) {
if (*argv[idx] == '\0')
error_msg_and_die("STRING2 cannot be empty");
output_length = expand(argv[idx], output);
map(input, input_length, output, output_length);
}
for (i = 0; i < input_length; i++)
invec[(int)input[i]] = TRUE;
for (i = 0; i < output_length; i++)
outvec[(int)output[i]] = 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.
*
*/