[src/trunk]: src/lib/libc/stdlib Fix various bugs with strfmon:

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/176a7e3a96b7
branches:  trunk
changeset: 828089:176a7e3a96b7
user:      christos <christos%NetBSD.org@localhost>
date:      Mon Nov 27 22:43:07 2017 +0000

description:
Fix various bugs with strfmon:
- Avoid out of bounds access for the currency_symbol[3] when the symbol
  is shorter (as it happens with the C locale where it is empty)
- Don't compare pointers to NUL, it is not helpful.
- Make the default sep_by_space 1 as suggested in:
      https://ftp.gnu.org/old-gnu/Manuals/glibc-2.2.3/html_node/libc_111.html
- Use the correct number of bytes for memmove(3)

XXX: pullup-8

diffstat:

 lib/libc/stdlib/strfmon.c |  23 +++++++++++++----------
 1 files changed, 13 insertions(+), 10 deletions(-)

diffs (75 lines):

diff -r db8aada25e46 -r 176a7e3a96b7 lib/libc/stdlib/strfmon.c
--- a/lib/libc/stdlib/strfmon.c Mon Nov 27 17:27:37 2017 +0000
+++ b/lib/libc/stdlib/strfmon.c Mon Nov 27 22:43:07 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: strfmon.c,v 1.11 2017/08/16 13:53:20 joerg Exp $       */
+/*     $NetBSD: strfmon.c,v 1.12 2017/11/27 22:43:07 christos Exp $    */
 
 /*-
  * Copyright (c) 2001 Alexey Zelkin <phantom%FreeBSD.org@localhost>
@@ -32,7 +32,7 @@
 #if 0
 __FBSDID("$FreeBSD: src/lib/libc/stdlib/strfmon.c,v 1.14 2003/03/20 08:18:55 ache Exp $");
 #else
-__RCSID("$NetBSD: strfmon.c,v 1.11 2017/08/16 13:53:20 joerg Exp $");
+__RCSID("$NetBSD: strfmon.c,v 1.12 2017/11/27 22:43:07 christos Exp $");
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -241,8 +241,12 @@
                        free(currency_symbol);
                if (flags & USE_INTL_CURRENCY) {
                        currency_symbol = strdup(lc->int_curr_symbol);
-                       if (currency_symbol != NULL)
-                               space_char = *(currency_symbol+3);
+                       if (currency_symbol != NULL &&
+                           strlen(currency_symbol) > 3) {
+                               space_char = currency_symbol[3];
+                               currency_symbol[3] = '\0';
+                       }
+
                } else
                        currency_symbol = strdup(lc->currency_symbol);
 
@@ -418,7 +422,7 @@
                *cs_precedes = lc->int_n_cs_precedes;
                *sep_by_space = lc->int_n_sep_by_space;
                *sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_n_sign_posn;
-               *signstr = (lc->negative_sign == '\0') ? "-"
+               *signstr = (*lc->negative_sign == '\0') ? "-"
                    : lc->negative_sign;
        } else if (flags & USE_INTL_CURRENCY) {
                *cs_precedes = lc->int_p_cs_precedes;
@@ -429,7 +433,7 @@
                *cs_precedes = lc->n_cs_precedes;
                *sep_by_space = lc->n_sep_by_space;
                *sign_posn = (flags & PARENTH_POSN) ? 0 : lc->n_sign_posn;
-               *signstr = (lc->negative_sign == '\0') ? "-"
+               *signstr = (*lc->negative_sign == '\0') ? "-"
                    : lc->negative_sign;
        } else {
                *cs_precedes = lc->p_cs_precedes;
@@ -438,11 +442,11 @@
                *signstr = lc->positive_sign;
        }
 
-       /* Set defult values for unspecified information. */
+       /* Set default values for unspecified information. */
        if (*cs_precedes != 0)
                *cs_precedes = 1;
        if ((unsigned char)*sep_by_space == NBCHAR_MAX)
-               *sep_by_space = 0;
+               *sep_by_space = 1;
        if ((unsigned char)*sign_posn == NBCHAR_MAX)
                *sign_posn = 0;
 }
@@ -615,8 +619,7 @@
                memset(bufend, pad_char, (size_t) padded);
        }
 
-       bufsize = bufsize - (bufend - rslt) + 1;
-       memmove(rslt, bufend, bufsize);
+       memmove(rslt, bufend, bufend - rslt + 1);
        free(avalue);
        return (rslt);
 }