minix/commands/simple/tr.c
2010-01-25 18:14:54 +00:00

224 lines
4.8 KiB
C

/* tr - translate characters Author: Michiel Huisjes */
/* Usage: tr [-cds] [string1 [string2]]
* c: take complement of string1
* d: delete input characters coded string1
* s: squeeze multiple output characters of string2 into one character
*/
#define BUFFER_SIZE 1024
#define ASCII 0377
typedef char BOOL;
#define TRUE 1
#define FALSE 0
#define NIL_PTR ((char *) 0)
BOOL com_fl, del_fl, sq_fl;
unsigned char output[BUFFER_SIZE], input[BUFFER_SIZE];
unsigned char vector[ASCII + 1];
BOOL invec[ASCII + 1], outvec[ASCII + 1];
short in_index, out_index;
#include <sys/types.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
_PROTOTYPE(int main, (int argc, char **argv));
_PROTOTYPE(void convert, (void));
_PROTOTYPE(void map, (unsigned char *string1, unsigned char *string2));
_PROTOTYPE(void expand, (char *arg, unsigned char *buffer));
_PROTOTYPE(void complement, (unsigned char *buffer));
int main(argc, argv)
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:
write(2,"Usage: tr [-cds] [string1 [string2]].\n", 38);
exit(1);
}
}
index++;
}
for (i = 0; i <= ASCII; i++) {
vector[i] = i;
invec[i] = outvec[i] = FALSE;
}
if (argv[index] != NIL_PTR) {
expand(argv[index++], input);
if (com_fl) complement(input);
if (argv[index] != NIL_PTR) expand(argv[index], output);
if (argv[index] != NIL_PTR) map(input, output);
for (ptr = input; *ptr; ptr++) invec[*ptr] = TRUE;
for (ptr = output; *ptr; ptr++) outvec[*ptr] = TRUE;
}
convert();
return(0);
}
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, BUFFER_SIZE)) <= 0) {
if (write(1, (char *)output, out_index) != out_index)
write(2, "Bad write\n", 10);
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 == BUFFER_SIZE) {
if (write(1, (char *)output, out_index) != out_index) {
write(2, "Bad write\n", 10);
exit(1);
}
out_index = 0;
}
}
/* NOTREACHED */
}
void map(string1, string2)
register unsigned char *string1, *string2;
{
unsigned char last;
while (*string1) {
if (*string2 == '\0')
vector[*string1] = last;
else
vector[*string1] = last = *string2++;
string1++;
}
}
static int starts_with(const char *s1, const char *s2)
{
while (*s1 && *s1 == *s2)
{
s1++;
s2++;
}
return *s1 == 0;
}
/*
* character classes from
* http://www.opengroup.org/onlinepubs/009695399/utilities/tr.html
* missing: blank, punct, cntrl, graph, print, space
*/
static struct
{
const char *keyword;
char first;
char last;
} expand_keywords[] = {
{ "[:alnum:]", 'A', 'Z' },
{ "[:alnum:]", 'a', 'z' },
{ "[:alnum:]", '0', '9' },
{ "[:alpha:]", 'A', 'Z' },
{ "[:alpha:]", 'a', 'z' },
{ "[:digit:]", '0', '9' },
{ "[:lower:]", 'a', 'z' },
{ "[:upper:]", 'A', 'Z' },
{ "[:xdigit:]", '0', '9' },
{ "[:xdigit:]", 'A', 'F' },
{ "[:xdigit:]", 'a', 'f' }
};
#define LENGTH(a) ((sizeof((a))) / (sizeof((a)[0])))
void expand(arg, buffer)
register char *arg;
register unsigned char *buffer;
{
int i, ac, keyword_index;
while (*arg) {
if (*arg == '\\') {
arg++;
i = ac = 0;
if (*arg >= '0' && *arg <= '7') {
do {
ac = (ac << 3) + *arg++ - '0';
i++;
} while (i < 4 && *arg >= '0' && *arg <= '7');
*buffer++ = ac;
} else if (*arg != '\0')
*buffer++ = *arg++;
} else if (*arg == '[') {
/* does one of the keywords match? */
keyword_index = -1;
for (i = 0; i < LENGTH(expand_keywords); i++)
if (starts_with(expand_keywords[i].keyword, arg))
{
/* we have a match, remember and expand */
keyword_index = i;
ac = expand_keywords[i].first;
while (ac <= expand_keywords[i].last)
*buffer++ = ac++;
}
/* skip keyword if found, otherwise expand range */
if (keyword_index >= 0)
arg += strlen(expand_keywords[keyword_index].keyword);
else
{
/* expand range */
arg++;
i = *arg++;
if (*arg++ != '-') {
*buffer++ = '[';
arg -= 2;
continue;
}
ac = *arg++;
while (i <= ac) *buffer++ = i++;
arg++; /* Skip ']' */
}
} else
*buffer++ = *arg++;
}
}
void complement(buffer)
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);
}