/* tr.c - translate or delete characters
*
* Copyright 2014 Sandeep Sharma <sandeep.jack2756@gmail.com>
*
* See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/tr.html
USE_TR(NEWTOY(tr, "^>2<1Ccsd[+cC]", TOYFLAG_USR|TOYFLAG_BIN))
config TR
bool "tr"
default n
help
usage: tr [-cds] SET1 [SET2]
Translate, squeeze, or delete characters from stdin, writing to stdout
-c/-C Take complement of SET1
-d Delete input characters coded SET1
-s Squeeze multiple output characters of SET2 into one character
*/
#define FOR_tr
#include "toys.h"
GLOBALS(
short map[256]; //map of chars
int len1, len2;
)
enum {
class_alpha, class_alnum, class_digit,
class_lower,class_upper,class_space,class_blank,
class_punct,class_cntrl,class_xdigit,class_invalid
};
static void map_translation(char *set1 , char *set2)
{
int i = TT.len1, k = 0;
if (toys.optflags & FLAG_d)
for (; i; i--, k++) TT.map[set1[k]] = set1[k]|0x100; //set delete bit
if (toys.optflags & FLAG_s) {
for (i = TT.len1, k = 0; i; i--, k++)
TT.map[set1[k]] = TT.map[set1[k]]|0x200;
for (i = TT.len2, k = 0; i; i--, k++)
TT.map[set2[k]] = TT.map[set2[k]]|0x200;
}
i = k = 0;
while (!(toys.optflags & FLAG_d) && set2 && TT.len1--) { //ignore set2 if -d present
TT.map[set1[i]] = ((TT.map[set1[i]] & 0xFF00) | set2[k]);
if (set2[k + 1]) k++;
i++;
}
}
static int handle_escape_char(char **esc_val) //taken from printf
{
char *ptr = *esc_val;
int esc_length = 0;
unsigned base = 0, num = 0, result = 0, count = 0;
if (*ptr == 'x') {
ptr++;
esc_length++;
base = 16;
} else if (isdigit(*ptr)) base = 8;
while (esc_length < 3 && base) {
num = tolower(*ptr) - '0';
if (num > 10) num += ('0' - 'a' + 10);
if (num >= base) {
if (base == 16) {
esc_length--;
if (!esc_length) {// Invalid hex value eg. /xvd, print as it is /xvd
result = '\\';
ptr--;
}
}
break;
}
esc_length++;
count = result = (count * base) + num;
ptr++;
}
if (base) {
ptr--;
*esc_val = ptr;
return (char)result;
} else {
switch (*ptr) {
case 'n': result = '\n'; break;
case 't': result = '\t'; break;
case 'e': result = (char)27; break;
case 'b': result = '\b'; break;
case 'a': result = '\a'; break;
case 'f': result = '\f'; break;
case 'v': result = '\v'; break;
case 'r': result = '\r'; break;
case '\\': result = '\\'; break;
default :
result = '\\';
ptr--; // Let pointer pointing to / we will increment after returning.
break;
}
}
*esc_val = ptr;
return (char)result;
}
static int find_class(char *class_name)
{
int i;
static char *class[] = {
"[:alpha:]","[:alnum:]","[:digit:]",
"[:lower:]","[:upper:]","[:space:]",
"[:blank:]","[:punct:]","[:cntrl:]",
"[:xdigit:]","NULL"
};
for (i = 0; i != class_invalid; i++) {
if (!memcmp(class_name, class[i], (class_name[0] == 'x')?10:9)) break;
}
return i;
}
static char *expand_set(char *arg, int *len)
{
int i = 0, j, k, size = 256;
char *set = xzalloc(size*sizeof(char));
while (*arg) {
if (i >= size) {
size += 256;
set = xrealloc(set, size);
}
if (*arg == '\\') {
arg++;
set[i++] = (int)handle_escape_char(&arg);
arg++;
continue;
}
if (arg[1] == '-') {
if (arg[2] == '\0') goto save;
j = arg[0];
k = arg[2];
if (j > k) perror_exit("reverse colating order");
while (j <= k) set[i++] = j++;
arg += 3;
continue;
}
if (arg[0] == '[' && arg[1] == ':') {
if ((j = find_class(arg)) == class_invalid) goto save;
if ((j == class_alpha) || (j == class_upper) || (j == class_alnum)) {
for (k = 'A'; k <= 'Z'; k++) set[i++] = k;
}
if ((j == class_alpha) || (j == class_lower) || (j == class_alnum)) {
for (k = 'a'; k <= 'z'; k++) set[i++] = k;
}
if ((j == class_alnum) || (j == class_digit) || (j == class_xdigit)) {
for (k = '0'; k <= '9'; k++) set[i++] = k;
}
if (j == class_space || j == class_blank) {
set[i++] = '\t';
if (j == class_space) {
set[i++] = '\n';
set[i++] = '\f';
set[i++] = '\r';
set[i++] = '\v';
}
set[i++] = ' ';
}
if (j == class_punct) {
for (k = 0; k <= 255; k++)
if (ispunct(k)) set[i++] = k;
}
if (j == class_cntrl) {
for (k = 0; k <= 255; k++)
if (iscntrl(k)) set[i++] = k;
}
if (j == class_xdigit) {
for (k = 'A'; k <= 'F'; k++) {
set[i + 6] = k | 0x20;
set[i++] = k;
}
i += 6;
arg += 10;
continue;
}
arg += 9; //never here for class_xdigit.
continue;
}
if (arg[0] == '[' && arg[1] == '=') { //[=char=] only
arg += 2;
if (*arg) set[i++] = *arg;
if (!arg[1] || arg[1] != '=' || arg[2] != ']')
error_exit("bad equiv class");
continue;
}
save:
set[i++] = *arg++;
}
*len = i;
return set;
}
static void print_map(char *set1, char *set2)
{
int r = 0, i, prev_char = -1;
while (1)
{
i = 0;
r = read(STDIN_FILENO, (toybuf), sizeof(toybuf));
if (!r) break;
for (;r > i;i++) {
if ((toys.optflags & FLAG_d) && (TT.map[(int)toybuf[i]] & 0x100)) continue;
if (toys.optflags & FLAG_s) {
if ((TT.map[(int)toybuf[i]] & 0x200) &&
(prev_char == TT.map[(int)toybuf[i]])) {
continue;
}
}
xputc(TT.map[(int)toybuf[i]] & 0xFF);
prev_char = TT.map[(int)toybuf[i]];
fflush(stdout);
}
}
}
static void do_complement(char **set)
{
int i, j;
char *comp = xmalloc(256);
for (i = 0, j = 0;i < 256; i++) {
if (memchr(*set, i, TT.len1)) continue;
else comp[j++] = (char)i;
}
free(*set);
TT.len1 = j;
*set = comp;
}
void tr_main(void)
{
char *set1, *set2 = NULL;
int i;
for (i = 0; i < 256; i++) TT.map[i] = i; //init map
set1 = expand_set(toys.optargs[0], &TT.len1);
if (toys.optflags & FLAG_c) do_complement(&set1);
if (toys.optargs[1]) {
if (toys.optargs[1][0] == '\0') error_exit("set2 can't be empty string");
set2 = expand_set(toys.optargs[1], &TT.len2);
}
map_translation(set1, set2);
print_map(set1, set2);
free(set1);
free(set2);
}