[src/trunk]: src/lib/libc/time KNF and additional comments

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

details:   https://anonhg.NetBSD.org/src/rev/061ac9bf59cc
branches:  trunk
changeset: 809551:061ac9bf59cc
user:      ginsbach <ginsbach%NetBSD.org@localhost>
date:      Mon Jul 20 14:37:11 2015 +0000

description:
KNF and additional comments

diffstat:

 lib/libc/time/strptime.c |  28 +++++++++++++++++++++-------
 1 files changed, 21 insertions(+), 7 deletions(-)

diffs (91 lines):

diff -r 5279de5eead5 -r 061ac9bf59cc lib/libc/time/strptime.c
--- a/lib/libc/time/strptime.c  Mon Jul 20 13:13:31 2015 +0000
+++ b/lib/libc/time/strptime.c  Mon Jul 20 14:37:11 2015 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: strptime.c,v 1.45 2015/07/15 13:54:38 ginsbach Exp $   */
+/*     $NetBSD: strptime.c,v 1.46 2015/07/20 14:37:11 ginsbach Exp $   */
 
 /*-
  * Copyright (c) 1997, 1998, 2005, 2008 The NetBSD Foundation, Inc.
@@ -31,7 +31,7 @@
 
 #include <sys/cdefs.h>
 #if defined(LIBC_SCCS) && !defined(lint)
-__RCSID("$NetBSD: strptime.c,v 1.45 2015/07/15 13:54:38 ginsbach Exp $");
+__RCSID("$NetBSD: strptime.c,v 1.46 2015/07/20 14:37:11 ginsbach Exp $");
 #endif
 
 #include "namespace.h"
@@ -50,6 +50,10 @@
 __weak_alias(strptime_l, _strptime_l)
 #endif
 
+static const u_char *conv_num(const unsigned char *, int *, uint, uint);
+static const u_char *find_string(const u_char *, int *, const char * const *,
+       const char * const *, int);
+
 #define _TIME_LOCALE(loc) \
     ((_TimeLocale *)((loc)->part_impl[(size_t)LC_TIME]))
 
@@ -83,12 +87,14 @@
        "EDT",    "CDT",    "MDT",    "PDT",    "\0\0\0"
 };
 
-static const u_char *conv_num(const unsigned char *, int *, uint, uint);
-static const u_char *find_string(const u_char *, int *, const char * const *,
-       const char * const *, int);
-
+/*
+ * Table to determine the ordinal date for the start of a month.
+ * Ref: http://en.wikipedia.org/wiki/ISO_week_date
+ */
 static const int start_of_month[2][13] = {
+       /* non-leap year */
        { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
+       /* leap year */
        { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
 };
 
@@ -586,11 +592,13 @@
 
        if (!HAVE_YDAY(state) && HAVE_YEAR(state)) {
                if (HAVE_MON(state) && HAVE_MDAY(state)) {
+                       /* calculate day of year (ordinal date) */
                        tm->tm_yday =  start_of_month[isleap_sum(tm->tm_year,
                            TM_YEAR_BASE)][tm->tm_mon] + (tm->tm_mday - 1);
                        state |= S_YDAY;
                } else if (day_offset != -1) {
-                       /* Set the date to the first Sunday (or Monday)
+                       /*
+                        * Set the date to the first Sunday (or Monday)
                         * of the specified week of the year.
                         */
                        if (!HAVE_WDAY(state)) {
@@ -607,7 +615,9 @@
 
        if (HAVE_YDAY(state) && HAVE_YEAR(state)) {
                int isleap;
+
                if (!HAVE_MON(state)) {
+                       /* calculate month of day of year */
                        i = 0;
                        isleap = isleap_sum(tm->tm_year, TM_YEAR_BASE);
                        while (tm->tm_yday >= start_of_month[isleap][i])
@@ -620,13 +630,17 @@
                        tm->tm_mon = i - 1;
                        state |= S_MON;
                }
+
                if (!HAVE_MDAY(state)) {
+                       /* calculate day of month */
                        isleap = isleap_sum(tm->tm_year, TM_YEAR_BASE);
                        tm->tm_mday = tm->tm_yday -
                            start_of_month[isleap][tm->tm_mon] + 1;
                        state |= S_MDAY;
                }
+
                if (!HAVE_WDAY(state)) {
+                       /* calculate day of week */
                        i = 0;
                        week_offset = first_wday_of(tm->tm_year);
                        while (i++ <= tm->tm_yday) {