Revamp tr(1) set parsing and handling

If you look at GNU coreutils, they do not support the mappings

	$ echo "1234abc" | tr "[:alnum:]" "[:upper:]"

	$ echo "ABCabc" | tr -c "[:upper:]" "[l*]"

to only give a few examples. This commit broadens the scope of tr(1)
as far as humanly possible to map between classes and non-classes,
making tr a usable tool and actually fulfilling user expectations.
Posix really is of no help here as it still kind of assumes the
fixed ASCII table instead of complex Unicode code points or even
Grapheme clusters.
This commit is contained in:
FRIGN 2016-10-05 21:18:24 +02:00
parent 9de401a495
commit bc4c293fe5
1 changed files with 57 additions and 47 deletions

104
tr.c
View File

@ -119,7 +119,7 @@ nextbrack:
}
/* REPEAT [_*n] (only allowed in set2) */
if (j - i > 2 && rstr[i + 2] == '*' && set1ranges > 0) {
if (j - i > 2 && rstr[i + 2] == '*') {
/* check if right side of '*' is a number */
q = 0;
factor = 1;
@ -138,7 +138,7 @@ nextbrack:
}
(*set)[setranges].start = rstr[i + 1];
(*set)[setranges].end = rstr[i + 1];
(*set)[setranges].quant = q ? q : setlen(set1, set1ranges);
(*set)[setranges].quant = q ? q : setlen(set1, MAX(set1ranges, 1));
setranges++;
i = j;
continue;
@ -196,69 +196,79 @@ main(int argc, char *argv[])
set1ranges = makeset(argv[0], &set1, &set1check);
if (argc == 2)
set2ranges = makeset(argv[1], &set2, &set2check);
if (dflag == sflag && !set2ranges && !set2check)
eprintf("set2 must be non-empty.\n");
if (argc == 2 && !set2check != !set1check)
eprintf("can't mix classes with non-classes.\n");
if (set2check && set2check != islowerrune && set2check != isupperrune)
eprintf("set2 can only be the 'lower' or 'upper' class.\n");
if (set2check && cflag && !dflag)
eprintf("set2 can't be imaged to from a complement.\n");
if (!dflag) {
/* sanity checks as we are translating */
if (!set2ranges && !set2check)
eprintf("cannot map to an empty set.\n");
if (set2check && set2check != islowerrune &&
set2check != isupperrune) {
eprintf("can only map to 'lower' and 'upper' class.\n");
}
}
read:
if (!efgetrune(&r, stdin, "<stdin>")) {
ret |= fshut(stdin, "<stdin>") | fshut(stdout, "<stdout>");
return ret;
}
off1 = off2 = 0;
for (i = 0; i < set1ranges; i++) {
for (i = 0, off1 = 0; i < set1ranges; i++, off1 += rangelen(set1[i])) {
if (set1[i].start <= r && r <= set1[i].end) {
if (dflag) {
if (!cflag)
goto read;
if (cflag)
continue;
else
goto write;
goto read;
}
if (cflag)
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;
if (sflag && (r == lastrune))
goto read;
/* map r to set2 */
if (set2check) {
if (set2check == islowerrune)
r = tolowerrune(r);
else
r = toupperrune(r);
} else {
off1 += r - set1[i].start;
if (off1 > setlen(set2, set2ranges) - 1) {
r = set2[set2ranges - 1].end;
goto write;
}
for (m = 0, off2 = 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 (set1check && set1check(r)) {
if (dflag) {
if (!cflag)
goto read;
if (dflag && !cflag)
goto read;
if (set2check) {
if (set2check == islowerrune)
r = tolowerrune(r);
else
goto write;
r = toupperrune(r);
} else {
r = set2[set2ranges - 1].end;
}
if (set1check == isupperrune && set2check == islowerrune)
r = tolowerrune(r);
else if (set1check == islowerrune && set2check == isupperrune)
r = toupperrune(r);
else if (set2ranges > 0)
r = cflag ? r : set2[set2ranges - 1].end;
else
eprintf("Misaligned character classes.\n");
} else if (cflag && set2ranges > 0) {
r = set2[set2ranges - 1].end;
}
if (!dflag && cflag) {
if (set2check) {
if (set2check == islowerrune)
r = tolowerrune(r);
else
r = toupperrune(r);
} else {
r = set2[set2ranges - 1].end;
}
goto write;
}
if (dflag && cflag)
goto read;