cal: added argument option for -w|--week to display that week

Because many years have two sections of week 52 or 53, the week that
this argument points to is the one that starts during that year (when available).
The week number in argument is also highlighted in addition to possibly visible
current/defined date highlighting.

Signed-off-by: Tommi Kyntola <kynde@iki.fi>

1 files changed, 99 insertions, 16 deletions

diff --git a/misc-utils/cal.c b/misc-utils/cal.c
index 92bd395e3..c4db0b13a 100644
--- a/misc-utils/cal.c
+++ b/misc-utils/cal.c
@@ -185,6 +185,7 @@ enum {
 #define	WEEK_LEN		(DAYS_IN_WEEK * DAY_LEN)
 #define	HEAD_SEP		2
 #define MONTH_COLS		3		/* month columns in year view */
+#define WNUM_LEN                3
 
 #define	J_DAY_LEN		4		/* 4 spaces per day */
 #define	J_WEEK_LEN		(DAYS_IN_WEEK * J_DAY_LEN)
@@ -226,8 +227,9 @@ static const int d_sep1752[MAXDAYS / 2] = {
 
 enum {
 	WEEK_NUM_DISABLED = 0,
-	WEEK_NUM_ISO,
-	WEEK_NUM_US
+	WEEK_NUM_MASK=0xff,
+	WEEK_NUM_ISO=0x100,
+	WEEK_NUM_US=0x200,
 };
 
 /* utf-8 can have up to 6 bytes per char; and an extra byte for ending \0 */
@@ -242,12 +244,14 @@ static int julian;
 /* function prototypes */
 static int leap_year(long year);
 static char * ascii_day(char *, int);
+static char * ascii_wnum(char *, int,int);
 static int center_str(const char* src, char* dest, size_t dest_size, size_t width);
 static void center(const char *, size_t, int);
 static void day_array(int, int, long, int *);
 static int day_in_week(int, int, long);
 static int day_in_year(int, int, long);
 static int week_number(int, int, long, int);
+static int week_to_day(int, long, int);
 static void yearly(int, long, int, int);
 static int do_monthly(int, int, long, int, struct fmt_st*, int);
 static void monthly(int, int, long, int);
@@ -263,7 +267,7 @@ int main(int argc, char **argv)
 	int ch, day = 0, month = 0, yflag = 0, wflag = WEEK_NUM_DISABLED;
 	long year;
 	int num_months = NUM_MONTHS;
-	int colormode = UL_COLORMODE_AUTO;
+	int colormode = UL_COLORMODE_AUTO, wnum = 0;
 
 	enum {
 		OPT_COLOR = CHAR_MAX + 1
@@ -276,7 +280,7 @@ int main(int argc, char **argv)
 		{"monday", no_argument, NULL, 'm'},
 		{"julian", no_argument, NULL, 'j'},
 		{"year", no_argument, NULL, 'y'},
-		{"week", no_argument, NULL, 'w'},
+		{"week", optional_argument, NULL, 'w'},
 		{"color", optional_argument, NULL, OPT_COLOR},
 		{"version", no_argument, NULL, 'V'},
 		{"help", no_argument, NULL, 'h'},
@@ -335,7 +339,7 @@ int main(int argc, char **argv)
 	}
 #endif
 
-	while ((ch = getopt_long(argc, argv, "13mjsywVh", longopts, NULL)) != -1)
+	while ((ch = getopt_long(argc, argv, "13mjsyw::Vh", longopts, NULL)) != -1)
 		switch(ch) {
 		case '1':
 			num_months = 1;		/* default */
@@ -356,6 +360,12 @@ int main(int argc, char **argv)
 			yflag = 1;
 			break;
 		case 'w':
+			if (optarg) {
+				wnum = strtos32_or_err(optarg,
+						_("invalid week argument"));
+				if (wnum < 1 || wnum > 53)
+					errx(EXIT_FAILURE,_("illegal week value: use 1-53"));
+			}
 			wflag = WEEK_NUM_US;	/* default per weekstart */
 			break;
 		case OPT_COLOR:
@@ -375,8 +385,10 @@ int main(int argc, char **argv)
 	argc -= optind;
 	argv += optind;
 
-	if (wflag)
-		wflag = (weekstart == MONDAY ? WEEK_NUM_ISO : WEEK_NUM_US);
+	if (wflag) {
+		wflag = wnum & WEEK_NUM_MASK;
+		wflag |= (weekstart == MONDAY ? WEEK_NUM_ISO : WEEK_NUM_US);
+	}
 
 	time(&now);
 	local_time = localtime(&now);
@@ -404,7 +416,7 @@ int main(int argc, char **argv)
 		} else if ((long) (local_time->tm_year + 1900) == year) {
 			day = local_time->tm_yday + 1;
 		}
-		if (!month)
+		if (!month && !wnum)
 			yflag=1;
 		break;
 	case 0:
@@ -415,10 +427,36 @@ int main(int argc, char **argv)
 	default:
 		usage(stderr);
 	}
+
+	if (wnum>0) {
+		int yday = week_to_day(wnum,year,wflag);
+		if (yday < 1)
+			errx(EXIT_FAILURE, _("illegal week value: year %ld doesn't have week %d"),year,wnum);
+		//day = yday; /* hightlight the first day of the week */
+		month = 1;
+		int leap = leap_year(year);
+		while (month <= 12 && yday > days_in_month[leap][month])
+			yday -= days_in_month[leap][month++];
+		if (month > 12) {
+			/* In some years (e.g. 2010 in ISO mode) it's possible to
+			 * have a remnant of week 53 starting the year yet the year
+			 * in question ends during 52, in this case we're assuming
+			 * that early remnant is being referred to if 53 is given as
+			 * argument. */
+			if (wnum == week_number(31,12,year-1,wflag)) {
+				month = 1;
+			} else
+				errx(EXIT_FAILURE, _("illegal week value: year %ld doesn't have week %d"),year,wnum);
+		}
+		//printf("%d %d %ld : %d : %d\n",day,month,year,wflag,wflag&WEEK_NUM_MASK);
+	}
+
 	headers_init(julian);
 
-	if (!colors_init(colormode))
+	if (!colors_init(colormode)) {
 		day = 0;
+		wflag &= ~WEEK_NUM_MASK;
+	}
 
 	if (yflag)
 		yearly(day, year, julian, wflag);
@@ -467,7 +505,7 @@ static int do_monthly(int day, int month, long year, int wflag,
 {
 	int col, row, days[MAXDAYS];
 	char *p, lineout[FMT_ST_CHARS];
-	size_t width = (julian ? J_WEEK_LEN : WEEK_LEN) - 1 + (wflag?3:0);
+	size_t width = (julian ? J_WEEK_LEN : WEEK_LEN) - 1 + (wflag?WNUM_LEN:0);
 	int pos = 0;
 
 	day_array(day, month, year, days);
@@ -500,9 +538,21 @@ static int do_monthly(int day, int month, long year, int wflag,
 			for (col = 0; col < DAYS_IN_WEEK; col++) {
 				int xd = days[row * DAYS_IN_WEEK + col];
 				if (xd != SPACE) {
-					p += sprintf(p,"%2d ",
-						week_number(xd & ~TODAY_FLAG,month,year,wflag));
+					int wnum = week_number(xd&~TODAY_FLAG,month,year,wflag);
+					p = ascii_wnum(p,wnum,(wflag & WEEK_NUM_MASK)==wnum);
 					break;
+					/*
+					int wnum = week_number(xd & ~TODAY_FLAG,month,year,wflag);
+					int highlight = 0;
+					if ((wflag&WEEK_NUM_MASK)==wnum) {
+						p += sprintf(p, "%s", Senter);
+						highlight = 1;
+					}
+					p += sprintf(p,"%2d",wnum);
+					if (highlight)
+						p += sprintf(p, "%s", Sexit);
+					p += sprintf(p," ");
+					break; */
 				} else if (col+1 == DAYS_IN_WEEK)
 					p += sprintf(p,"   ");
 			}
@@ -617,7 +667,7 @@ static void yearly(int day, long year, int julian, int wflag)
 	int days[MONTHS_IN_YEAR][MAXDAYS];
 	char *p;
 	/* three weeks + separators + \0 */
-	int wnumlen = (wflag?3:0);
+	int wnumlen = (wflag?WNUM_LEN:0);
 	char lineout[ wnumlen + sizeof(day_headings) + 2 +
 		      wnumlen + sizeof(day_headings) + 2 +
 		      wnumlen + sizeof(day_headings) + 1 ];
@@ -669,8 +719,8 @@ static void yearly(int day, long year, int julian, int wflag)
 					for (col = 0; col < DAYS_IN_WEEK; col++) {
 						int xd = days[month + which_cal][row * DAYS_IN_WEEK + col];
 						if (xd != SPACE) {
-							p += sprintf(p,"%2d ",
-								week_number(xd & ~TODAY_FLAG,month + which_cal + 1,year,wflag));
+							int wnum = week_number(xd&~TODAY_FLAG,month+which_cal+1,year,wflag);
+							p = ascii_wnum(p,wnum,(wflag & WEEK_NUM_MASK)==wnum);
 							break;
 						} else if (col+1 == DAYS_IN_WEEK)
 							p += sprintf(p,"   ");
@@ -779,7 +829,7 @@ static int day_in_week(int d, int m, long y)
 static int week_number(int day, int month, long year, int wflag) {
 	int fday = 0,wday,yday;
 	wday = day_in_week(1,1,year);
-	if (wflag == WEEK_NUM_ISO)
+	if (wflag & WEEK_NUM_ISO)
 		fday = wday + (wday>=FRIDAY?-2:5);
 	else	/* WEEK_NUM_US */
 		/* according to gcal, the first Sun is in the first week */
@@ -811,6 +861,27 @@ static int week_number(int day, int month, long year, int wflag) {
 	return (yday+fday) / 7;
 }
 
+/*
+ * week_to_day
+ *      return the yday of the first day in a given week inside
+ *      the given year. This may be something other than Monday
+ *      for ISO-8601 modes. For North American numbering this
+ *      always returns a Sunday.
+ */
+static int week_to_day(int wnum, long year, int wflag) {
+	int yday, wday;
+	wday = day_in_week(1,1,year);
+	yday = wnum * 7 - wday;
+	if (wflag & WEEK_NUM_ISO)
+		yday -= (wday>=FRIDAY?-2:5);
+	else	/* WEEK_NUM_US */
+		yday -= (wday==SUNDAY?6:-1);
+	if (yday<=0)
+		return 1;
+
+	return yday;
+}
+
 static char *ascii_day(char *p, int day)
 {
 	int display, val;
@@ -859,6 +930,18 @@ static char *ascii_day(char *p, int day)
 	return p;
 }
 
+static char * ascii_wnum(char *p, int wnum,int highlight)
+{
+	if (highlight)
+		p += sprintf(p,"%s",Senter);
+	p += sprintf(p,"%2d",wnum);
+	if (highlight)
+		p += sprintf(p,"%s ",Sexit);
+	else
+		p += sprintf(p," ");
+	return p;
+}
+
 /*
  * Center string, handling multibyte characters appropriately.
  * In addition if the string is too large for the width it's truncated.