sbase/tr.c
2015-01-10 19:56:34 +00:00

244 lines
4.6 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include "utf.h"
#include "util.h"
static int cflag = 0;
static int dflag = 0;
static int sflag = 0;
struct range {
Rune start;
Rune end;
size_t quant;
};
#define DIGIT "0-9"
#define UPPER "A-Z"
#define LOWER "a-z"
#define PUNCT "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~"
#define ALNUM DIGIT UPPER LOWER
static struct {
char *name;
char *str;
} classes[] = {
{ "alnum", ALNUM },
{ "alpha", UPPER LOWER },
{ "blank", " \t" },
{ "cntrl", "\000-\037\177" },
{ "digit", DIGIT },
{ "graph", ALNUM PUNCT },
{ "lower", LOWER },
{ "print", ALNUM PUNCT " " },
{ "punct", PUNCT },
{ "space", "\t\n\v\f\r" },
{ "upper", UPPER },
{ "xdigit", DIGIT "A-Fa-f" },
};
static struct range *set1 = NULL;
static size_t set1ranges = 0;
static struct range *set2 = NULL;
static size_t set2ranges = 0;
static size_t
rangelen(struct range r)
{
return (r.end - r.start + 1) * r.quant;
}
static size_t
setlen(struct range *set, size_t setranges)
{
size_t len = 0, i;
for (i = 0; i < setranges; i++)
len += rangelen(set[i]);
return len;
}
static int
rstrmatch(Rune *r, char *s, size_t n)
{
size_t i;
for (i = 0; i < n; i++)
if (r[i] != s[i])
return 0;
return 1;
}
static size_t
makeset(char *str, struct range **set)
{
Rune *rstr;
size_t len, i, j, m, n;
size_t q, setranges;
int factor, base;
reset:
setranges = 0;
/* rstr defines at most len ranges */
len = chartorunearr(str, &rstr);
*set = emalloc(len * sizeof(**set));
/* todo: allow expressions */
for (i = 0; i < len; i++) {
if (rstr[i] == '[') {
j = i;
nextbrack:
if (j == len)
goto literal;
for (m = j; m < len; m++)
if (rstr[m] == ']') {
j = m;
break;
}
if (j == i)
goto literal;
/* CLASSES [=EQUIV=] (skip) */
if (j - i > 3 && rstr[i + 1] == '=' && rstr[m - 1] == '=') {
i = j;
continue;
}
/* CLASSES [:CLASS:] */
if (j - i > 3 && rstr[i + 1] == ':' && rstr[m - 1] == ':') {
for (n = 0; n < LEN(classes); n++) {
if (rstrmatch(rstr + i + 2, classes[n].name, j - i - 3)) {
str = classes[n].str;
goto reset;
}
}
eprintf("Invalid character class\n");
}
/* REPEAT [_*n] (only allowed in set2) */
if (j - i > 2 && rstr[i + 2] == '*' && set1ranges > 0) {
/* check if right side of '*' is a number */
q = 0;
factor = 1;
base = (rstr[i + 3] == '0') ? 8 : 10;
for (n = j - 1; n > i + 2; n--) {
if (rstr[n] < '0' && rstr[n] > '9') {
n = 0;
break;
}
q += (rstr[n] - '0') * factor;
factor *= base;
}
if (n == 0) {
j = m + 1;
goto nextbrack;
}
(*set)[setranges].start = rstr[i + 1];
(*set)[setranges].end = rstr[i + 1];
(*set)[setranges].quant = q ? q : setlen(set1, set1ranges);
setranges++;
i = j;
continue;
}
j = m + 1;
goto nextbrack;
}
literal:
/* RANGES [_-__-_], _-__-_ */
/* LITERALS _______ */
(*set)[setranges].start = rstr[i];
if (i < len - 2 && rstr[i + 1] == '-' && rstr[i + 2] >= rstr[i])
i += 2;
(*set)[setranges].end = rstr[i];
(*set)[setranges].quant = 1;
setranges++;
}
free(rstr);
return setranges;
}
static void
usage(void)
{
eprintf("usage: %s [-cCds] set1 [set2]\n", argv0);
}
int
main(int argc, char *argv[])
{
Rune r = 0, lastrune = 0;
size_t off1, off2, i, m;
ARGBEGIN {
case 'c':
case 'C':
cflag = 1;
break;
case 'd':
dflag = 1;
break;
case 's':
sflag = 1;
break;
default:
usage();
} ARGEND;
if (argc < 1 || argc > 2 || (argc == 1 && dflag == sflag))
usage();
set1ranges = makeset(argv[0], &set1);
if (argc == 2)
set2ranges = makeset(argv[1], &set2);
if (!dflag && !set2ranges)
eprintf("set2 must be non-empty\n");
read:
if (!readrune("<stdin>", stdin, &r))
return 0;
off1 = off2 = 0;
for (i = 0; i < set1ranges; i++) {
if (set1[i].start <= r && r <= set1[i].end) {
if (dflag && !cflag)
goto read;
if (sflag) {
if (r == lastrune)
goto read;
else
goto write;
}
for (m = 0; m < i; m++)
off1 += rangelen(set1[m]);
off1 += r - set1[m].start;
if (off1 > setlen(set2, set2ranges) - 1) {
r = set2[set2ranges - 1].end;
goto write;
}
for (m = 0; m < set2ranges; m++) {
if (off2 + rangelen(set2[m]) > off1) {
m++;
break;
}
off2 += rangelen(set2[m]);
}
m--;
r = set2[m].start + (off1 - off2) / set2[m].quant;
goto write;
}
}
if (dflag && cflag)
goto read;
if (dflag && sflag && r == lastrune)
goto read;
write:
lastrune = r;
writerune("<stdout>", stdout, &r);
goto read;
}