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	libutil/unescape: Stop octal escape at 3 digits - sbase - suckless unix tools
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	---
	commit 948e5161902920705f0c3a6458533fc017452173
	parent f3bf46b44b5cd14068c9d48ddd7ffb1c7e4b26ca
	Author: Michael Forney <[email protected]>
	Date: Mon, 21 Apr 2025 10:31:40 -0700

	libutil/unescape: Stop octal escape at 3 digits

	unescape() is used by several tools, in particular printf(1) and
	tr(1), which should stop the octal escape at a maximum of 3 digits:

	printf(1)
	> In addition to the escape sequences shown in XBD 5. File Format
	> Notation ('\\', '\a', '\b', '\f', '\n', '\r', '\t', '\v'), "\ddd",
	> where ddd is a one, two, or three-digit octal number, shall be
	> written as a byte with the numeric value specified by the octal
	> number.

	tr(1)
	> An octal sequence shall consist of a <backslash> followed by the
	> longest sequence of one, two, or three-octal-digit characters.

	Previously, the maximum was set to 4 (possibly a typo?), which meant
	that printf '\0123' printed `S` instead of `<newline>3`.

	To check that this doesn't break any other tools using unescape:

	- cut: used for -d parameter, escapes are non-standard
	- join: used for -t parameter, escapes are non-standard
	- nl: used for -s parameter, escapes are non-standard
	- paste: used for -d parameter, POSIX specifies \n, \t, \\, and \0,
	\0 followed by a digit is unspecified
	- sort: used for -t parameter, escapes are non-standard

	Diffstat:
	M libutil/unescape.c \| 2 +-

	1 file changed, 1 insertion(+), 1 deletion(-)
	---
	diff --git a/libutil/unescape.c b/libutil/unescape.c
	@@ -37,7 +37,7 @@ unescape(char *s)
	} else if (escapes[(unsigned char)*r]) {
	w++ = escapes[(unsigned char)r++];
	} else if (is_odigit(*r)) {
	- for (q = 0, m = 4; m && is_odigit(*r); m--, r++)
	+ for (q = 0, m = 3; m && is_odigit(*r); m--, r++)
	q = q * 8 + (*r - '0');
	*w++ = MIN(q, 255);
	} else if (*r == 'x' && isxdigit(r[1])) {