migrate to gitlab

1 files changed, 188 insertions, 0 deletions

diff --git a/cal.c b/cal.c
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index 0000000..fb88f2b
--- /dev/null
+++ b/cal.c
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+/*
+ * UNG's Not GNU
+ * 
+ * Copyright (c) 2011-2017, Jakob Kaivo <jkk@ung.org>
+ * 
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#define _XOPEN_SOURCE 700
+#include <locale.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+
+#define MONTHWIDTH (20)
+#define MONTHHEIGHT (8)
+#define COLUMNS (3)
+#define COLUMNSEP "  "
+
+/*d print a calendar d*/
+/*a month a*/
+/*a year a*/
+
+/* FIXME: Sep 1752 cuts off after the 27th */
+
+static char displaymonth[COLUMNS][MONTHHEIGHT][MONTHWIDTH+2];
+
+static int daysin(int year, int month)
+{
+	int mdays[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
+	if (month == 1 && ((year % 4 == 0 && year % 400 == 0)
+	    || (year % 4 == 0 && year % 100 != 0))) {
+	    return 29;
+	}
+	return mdays[month];
+}
+
+static int dow(int y, int m, int d)
+{
+	int t[] = { 0, 3, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4 };
+	int shift = 0;
+
+	/* Julian dates prior to 1752-09-14 (1752-09-02 is the day before) */
+	if (y < 1752 || (y == 1752 && m < 9) || (y == 1752 && m == 9 && d < 14)) {
+		shift = 3;
+	}
+
+	y -= m < 3;
+	return ((y + (y / 4) - (y / 100) + (y / 400) + t[m - 1] + d) - shift) % 7;
+}
+
+static char *center(char *s, size_t n)
+{
+	char centered[n+1];
+	size_t len = strlen(s);
+	size_t lpad = (n - len) / 2;
+	memset(centered, ' ', n);
+	strcpy(centered + lpad, s);
+	centered[lpad + len] = ' ';
+	centered[n] = '\0';
+	return strcpy(s, centered);
+}
+
+static int cal_week(char *buf, int year, int month, int week)
+{
+	int first = dow(year, month, 1);
+	int start = (week * 7) - first;
+	int chars = 0;
+
+	if (start < 0) {
+		start = 0;
+	}
+
+	int days = daysin(year, month - 1);
+
+	if (week == 0) {
+		for (int day = 0; day < first; day++) {
+			chars += sprintf(buf + chars, "   ");
+		}
+	}
+
+	for (int day = start + 1; day < start + 8; day++) {
+		int shift = 0;
+		/* Julian dates prior to 1752-09-14 (1752-09-02 is the day before) */
+		if (year == 1752 && month == 9 && day > 2) {
+			shift = 11;
+		}
+
+		if (day + shift > days) {
+			return chars;
+		}
+
+		chars += snprintf(buf + chars, MONTHWIDTH+1-chars, "%2d%s", day + shift, dow(year, month, day) == 6 ? "" : " ");
+
+		if (dow(year, month, day) == 6) {
+			return chars;
+		}
+	}
+
+	return 0;
+}
+
+void genmonth(struct tm *tm, int withyear)
+{
+	strftime(displaymonth[tm->tm_mon % COLUMNS][0], MONTHWIDTH, withyear ? "%B %Y" : "%B", tm);
+	center(displaymonth[tm->tm_mon % COLUMNS][0], MONTHWIDTH);
+
+	char *header = "Su Mo Tu We Th Fr Sa";
+	strcpy(displaymonth[tm->tm_mon % COLUMNS][1], header);
+
+	for (int i = 0; i < MONTHHEIGHT-2; i++) {
+		memset(displaymonth[tm->tm_mon % COLUMNS][i+2], ' ', MONTHWIDTH);
+		cal_week(displaymonth[tm->tm_mon % COLUMNS][i+2], tm->tm_year + 1900, tm->tm_mon + 1, i);
+		displaymonth[tm->tm_mon % COLUMNS][i+2][strlen(displaymonth[tm->tm_mon % COLUMNS][i+2])] = ' ';
+		displaymonth[tm->tm_mon % COLUMNS][i+2][MONTHWIDTH] = '\0';
+	}
+}
+
+int main(int argc, char *argv[])
+{
+	while (getopt(argc, argv, "") != -1) {
+		return 1;
+	}
+
+	time_t now = time(NULL);
+	struct tm *tm = localtime(&now);
+	tm->tm_mday = 1;
+
+	if (argc > optind + 2) {
+		return 1;
+	}
+
+	if (argc > optind) {
+		tm->tm_year = atoi(argv[argc-1]) - 1900;
+		if (tm->tm_year > 9999-1900 || tm->tm_year < 1-1900) {
+			return 1;
+		}
+	}
+
+	setlocale(LC_ALL, "");
+
+	if (argc > optind + 1) {
+		tm->tm_mon = atoi(argv[optind]) - 1;
+		if (tm->tm_mon > 11 || tm->tm_mon < 0) {
+			return 1;
+		}
+	}
+
+	if (argc != optind + 1) {
+		genmonth(tm, 1);
+		for (int i = 0; i < MONTHHEIGHT; i++) {
+			puts(displaymonth[tm->tm_mon % COLUMNS][i]);
+		}
+		return 0;
+	}
+
+	char year[MONTHWIDTH * COLUMNS + (sizeof(COLUMNSEP) - 1) * (COLUMNS - 1)] = {0};
+	strftime(year, sizeof(year), "%Y", tm);
+	printf("%s\n\n", center(year, sizeof(year)));
+
+	tm->tm_mon = 0;
+	while (tm->tm_mon < 12) {
+		for (int row = 0; row < MONTHHEIGHT; row++) {
+			for (int col = 0; col < COLUMNS; col++) {
+				if (row == 0) {
+					genmonth(tm, 0);
+					tm->tm_mon++;
+				}
+				printf("%s%s", displaymonth[col][row], col == 2 ? "\n" : COLUMNSEP);
+			}
+		}
+	}
+
+	return 0;
+}