Import sources from 2011-03-30 iso image

1 files changed, 202 insertions, 0 deletions

diff --git a/sys/src/ape/lib/ap/gen/strftime.c b/sys/src/ape/lib/ap/gen/strftime.c
new file mode 100755
index 000000000..f86606089
--- /dev/null
+++ b/sys/src/ape/lib/ap/gen/strftime.c
@@ -0,0 +1,202 @@
+#include <time.h>
+#include <string.h>
+
+static char *awday[7] = { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" };
+static char *wday[7] = { "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday",
+			"Friday", "Saturday"};
+static char *amon[12] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
+			    "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
+static char *mon[12] = {"January", "February", "March", "April", "May", "June",
+		"July", "August", "September", "October", "November", "December"};
+static char *ampm[2] = {"AM", "PM"};
+static char *tz[2] = {"EST", "EDT"};
+
+static int jan1(int);
+static char *strval(char *, char *, char **, int, int);
+static char *dval(char *, char *, int, int);
+
+size_t
+strftime(char *s, size_t maxsize, const char *format, const struct tm *t)
+{
+	char *sp, *se, *fp;
+	int i;
+
+	sp = s;
+	se = s+maxsize;
+	for(fp=(char *)format; *fp && sp<se; fp++){
+		if(*fp != '%')
+			*sp++ = *fp;
+		else switch(*++fp){
+			case 'a':
+				sp = strval(sp, se, awday, t->tm_wday, 7);
+				break;
+			case 'A':
+				sp = strval(sp, se, wday, t->tm_wday, 7);
+				break;
+			case 'b':
+				sp = strval(sp, se, amon, t->tm_mon, 12);
+				break;
+			case 'B':
+				sp = strval(sp, se, mon, t->tm_mon, 12);
+				break;
+			case 'c':
+				sp += strftime(sp, se-sp, "%a %b %d %H:%M:%S %Y", t);
+				break;
+			case 'd':
+				sp = dval(sp, se, t->tm_mday, 2);
+				break;
+			case 'H':
+				sp = dval(sp, se, t->tm_hour, 2);
+				break;
+			case 'I':
+				i = t->tm_hour;
+				if(i == 0)
+					i = 12;
+				else if(i > 12)
+					i -= 12;
+				sp = dval(sp, se, i, 2);
+				break;
+			case 'j':
+				sp = dval(sp, se, t->tm_yday+1, 3);
+				break;
+			case 'm':
+				sp = dval(sp, se, t->tm_mon+1, 2);
+				break;
+			case 'M':
+				sp = dval(sp, se, t->tm_min, 2);
+				break;
+			case 'p':
+				i = (t->tm_hour < 12)? 0 : 1;
+				sp = strval(sp, se, ampm, i, 2);
+				break;
+			case 'S':
+				sp = dval(sp, se, t->tm_sec, 2);
+				break;
+			case 'U':
+				i = 7-jan1(t->tm_year);
+				if(i == 7)
+					i = 0;
+				/* Now i is yday number of first sunday in year */
+				if(t->tm_yday < i)
+					i = 0;
+				else
+					i = (t->tm_yday-i)/7 + 1;
+				sp = dval(sp, se, i, 2);
+				break;
+			case 'w':
+				sp = dval(sp, se, t->tm_wday, 1);
+				break;
+			case 'W':
+				i = 8-jan1(t->tm_year);
+				if(i >= 7)
+					i -= 7;
+				/* Now i is yday number of first monday in year */
+				if(t->tm_yday < i)
+					i = 0;
+				else
+					i = (t->tm_yday-i)/7 + 1;
+				sp = dval(sp, se, i, 2);
+				break;
+			case 'x':
+				sp += strftime(sp, se-sp, "%a %b %d, %Y", t);
+				break;
+			case 'X':
+				sp += strftime(sp, se-sp, "%H:%M:%S", t);
+				break;
+			case 'y':
+				sp = dval(sp, se, t->tm_year%100, 2);
+				break;
+			case 'Y':
+				sp = dval(sp, se, t->tm_year+1900, 4);
+				break;
+			case 'Z':
+				/* hack for now: assume eastern time zone */
+				i = t->tm_isdst? 1 : 0;
+				sp = strval(sp, se, tz, i, 2);
+				break;
+			case 0:
+				fp--; /* stop loop after next fp incr */
+				break;
+			default:
+				*sp++ = *fp;
+			}
+	}
+	if(*fp)
+		sp = s; /* format string didn't end: no room for conversion */
+	if(sp<se)
+		*sp = 0;
+	return sp-s;
+}
+
+static char *
+strval(char *start, char *end, char **array, int index, int alen)
+{
+	int n;
+
+	if(index<0 || index>=alen){
+		*start = '?';
+		return start+1;
+	}
+	n = strlen(array[index]);
+	if(n > end-start)
+		n = end-start;
+	memcpy(start, array[index], n);
+	return start+n;
+}
+
+static char *
+dval(char *start, char *end, int val, int width)
+{
+	char *p;
+
+	if(val<0 || end-start<width){
+		*start = '?';
+		return start+1;
+	}
+	p = start+width-1;
+	while(p>=start){
+		*p-- = val%10 + '0';
+		val /= 10;
+	}
+	if(val>0)
+		*start = '*';
+	return start+width;
+}
+
+/*
+ *	return day of the week
+ *	of jan 1 of given year
+ */
+static int
+jan1(int yr)
+{
+	int y, d;
+
+/*
+ *	normal gregorian calendar
+ *	one extra day per four years
+ */
+
+	y = yr+1900;
+	d = 4+y+(y+3)/4;
+
+/*
+ *	julian calendar
+ *	regular gregorian
+ *	less three days per 400
+ */
+
+	if(y > 1800) {
+		d -= (y-1701)/100;
+		d += (y-1601)/400;
+	}
+
+/*
+ *	great calendar changeover instant
+ */
+
+	if(y > 1752)
+		d += 3;
+
+	return(d%7);
+}