[src/trunk]: src/common/lib/libutil Fix an off-by-one in the F modifier that ...

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

details:   https://anonhg.NetBSD.org/src/rev/b2c5ab7ab277
branches:  trunk
changeset: 450870:b2c5ab7ab277
user:      christos <christos%NetBSD.org@localhost>
date:      Sat Apr 27 17:45:28 2019 +0000

description:
Fix an off-by-one in the F modifier that ended up skipping the first : or =
entry, and add a * specifier for a "default case".

diffstat:

 common/lib/libutil/snprintb.c |  41 ++++++++++++++++++++++++++---------------
 1 files changed, 26 insertions(+), 15 deletions(-)

diffs (107 lines):

diff -r d7399209ca2c -r b2c5ab7ab277 common/lib/libutil/snprintb.c
--- a/common/lib/libutil/snprintb.c     Sat Apr 27 17:30:38 2019 +0000
+++ b/common/lib/libutil/snprintb.c     Sat Apr 27 17:45:28 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: snprintb.c,v 1.18 2018/07/26 00:33:26 kamil Exp $      */
+/*     $NetBSD: snprintb.c,v 1.19 2019/04/27 17:45:28 christos Exp $   */
 
 /*-
  * Copyright (c) 2002 The NetBSD Foundation, Inc.
@@ -41,7 +41,7 @@
 
 #  include <sys/cdefs.h>
 #  if defined(LIBC_SCCS) && !defined(lint)
-__RCSID("$NetBSD: snprintb.c,v 1.18 2018/07/26 00:33:26 kamil Exp $");
+__RCSID("$NetBSD: snprintb.c,v 1.19 2019/04/27 17:45:28 christos Exp $");
 #  endif
 
 #  include <sys/types.h>
@@ -51,7 +51,7 @@
 #  include <errno.h>
 # else /* ! _KERNEL */
 #  include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: snprintb.c,v 1.18 2018/07/26 00:33:26 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: snprintb.c,v 1.19 2019/04/27 17:45:28 christos Exp $");
 #  include <sys/param.h>
 #  include <sys/inttypes.h>
 #  include <sys/systm.h>
@@ -67,7 +67,7 @@
        const char *c_fmt, *s_fmt = NULL, *cur_fmt;
        const char *sbase;
        int bit, ch, t_len, s_len = 0, l_len, f_len, v_len, sep;
-       int restart = 0;
+       int restart = 0, matched = 1;
        uint64_t field;
 
 #ifdef _KERNEL
@@ -166,6 +166,16 @@
                        if (restart)                                    \
                                break;                                  \
                }
+#define FMTSTR(sb, f)                                                  \
+       do {                                                            \
+               f_len = snprintf(bp, buflen - t_len, sb, (int)f);       \
+               if (f_len < 0)                                          \
+                       goto internal;                                  \
+               t_len += f_len;                                         \
+               l_len += f_len;                                         \
+               if ((size_t)t_len < buflen)                             \
+                       bp += f_len;                                    \
+       } while (/*CONSTCOND*/0)
 
        /*
         * Chris Torek's new bitmask format is identified by a leading \177
@@ -208,6 +218,7 @@
                                break;
                        case 'f':
                        case 'F':
+                               matched = 0;
                                cur_fmt = c_fmt;
                                f_len = *bitfmt++;      /* field length */
                                field = (val >> bit) &
@@ -215,23 +226,14 @@
                                PUTSEP;
                                if (restart == 0)
                                        sep = ',';
-                               if (ch == 'F') {        /* just extract */
-                                       bitfmt--;
+                               if (ch == 'F')          /* just extract */
                                        break;
-                               }
                                if (restart == 0)
                                        PUTS(bitfmt);
                                if (restart == 0)
                                        PUTCHR('=');
                                if (restart == 0) {
-                                       f_len = snprintf(bp, buflen - t_len,
-                                                        sbase, field);
-                                       if (f_len < 0)
-                                               goto internal;
-                                       t_len += f_len;
-                                       l_len += f_len;
-                                       if ((size_t)t_len < buflen)
-                                               bp += f_len;
+                                       FMTSTR(sbase, field);
                                        if (l_max > 0 && (size_t)l_len > l_max)
                                                PUTCHR('#');
                                }
@@ -246,10 +248,19 @@
                                 */
                                if ((int)field != bit)
                                        goto skip;
+                               matched = 1;
                                if (ch == '=')
                                        PUTCHR('=');
                                PUTS(bitfmt);
                                break;
+                       case '*':
+                               bitfmt--;
+                               if (!matched) {
+                                       matched = 1;
+                                       FMTSTR(bitfmt, field);
+                                       break;
+                               }
+                               /*FALLTHROUGH*/
                        default:
                        skip:
                                while (*bitfmt++ != '\0')