From: Rich Felker <dalias@aerifal.cx>
Date: Sat, 15 Nov 2014 17:16:19 +0000 (-0500)
Subject: fix behavior of printf with alt-form octal, zero precision, zero value
X-Git-Tag: v1.0.5~21
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=395e409cc0b89faeaae8d701a18105d020f7aade;p=oweals%2Fmusl.git

fix behavior of printf with alt-form octal, zero precision, zero value

in this case there are two conflicting rules in play: that an explicit
precision of zero with the value zero produces no output, and that the
'#' modifier for octal increases the precision sufficiently to yield a
leading zero. ISO C (7.19.6.1 paragraph 6 in C99+TC3) includes a
parenthetical remark to clarify that the precision-increasing behavior
takes precedence, but the corresponding text in POSIX off of which I
based the implementation is missing this remark.

this issue was covered in WG14 DR#151.

(cherry picked from commit b91cdbe2bc8b626aa04dc6e3e84345accf34e4b1)
---

diff --git a/src/stdio/vfprintf.c b/src/stdio/vfprintf.c
index f6e7f38d..9f02f743 100644
--- a/src/stdio/vfprintf.c
+++ b/src/stdio/vfprintf.c
@@ -572,7 +572,7 @@ static int printf_core(FILE *f, const char *fmt, va_list *ap, union arg *nl_arg,
 			if (0) {
 		case 'o':
 			a = fmt_o(arg.i, z);
-			if ((fl&ALT_FORM) && arg.i) prefix+=5, pl=1;
+			if ((fl&ALT_FORM) && p<z-a+1) p=z-a+1;
 			} if (0) {
 		case 'd': case 'i':
 			pl=1;