Changes in uspace/lib/posix/time.c [d3e3a71:d4d74dc] in mainline

File:

• uspace/lib/posix/time.c (modified) (14 diffs)

uspace/lib/posix/time.c

@@ -45 +45 @@
 #include "errno.h"
 #include "signal.h"
+#include "assert.h"
 
 #include "libc/malloc.h"
@@ -140 +141 @@
  * Used by some functions in this file.
  *
- * @param op1 Dividend.
+ * @param op1 Divident.
  * @param op2 Divisor.
  * @return Rounded quotient.
@@ -157 +158 @@
  * Used by some functions in this file.
  *
- * @param op1 Dividend.
+ * @param op1 Divident.
  * @param op2 Divisor.
  * @return Remainder.
@@ -195 +196 @@
 
 /**
+ * Seconds since the Epoch. see also _days_since_epoch().
+ * 
+ * @param tm Normalized broken-down time.
+ * @return Number of seconds since the epoch, not counting leap seconds.
+ */
+static time_t _secs_since_epoch(const struct posix_tm *tm)
+{
+        return _days_since_epoch(tm->tm_year, tm->tm_mon, tm->tm_mday) *
+            SECS_PER_DAY + tm->tm_hour * SECS_PER_HOUR +
+            tm->tm_min * SECS_PER_MIN + tm->tm_sec;
+}
+
+/**
  * Which day of week the specified date is.
  * 
@@ -216 +230 @@
  * @return 0 on success, -1 on overflow
  */
-static int _normalize_time(struct tm *tm, time_t sec_add)
+static int _normalize_time(struct posix_tm *tm, time_t sec_add)
 {
         // TODO: DST correction
@@ -292 +306 @@
 }
 
+/**
+ * Which day the week-based year starts on, relative to the first calendar day.
+ * E.g. if the year starts on December 31st, the return value is -1.
+ *
+ * @param Year since 1900.
+ * @return Offset of week-based year relative to calendar year.
+ */
+static int _wbyear_offset(int year)
+{
+        int start_wday = _day_of_week(year, 0, 1);
+        return _floor_mod(4 - start_wday, 7) - 3;
+}
+
+/**
+ * Returns week-based year of the specified time.
+ *
+ * @param tm Normalized broken-down time.
+ * @return Week-based year.
+ */
+static int _wbyear(const struct posix_tm *tm)
+{
+        int day = tm->tm_yday - _wbyear_offset(tm->tm_year);
+        if (day < 0) {
+                /* Last week of previous year. */
+                return tm->tm_year - 1;
+        }
+        if (day > 364 + _is_leap_year(tm->tm_year)) {
+                /* First week of next year. */
+                return tm->tm_year + 1;
+        }
+        /* All the other days are in the calendar year. */
+        return tm->tm_year;
+}
+
+/**
+ * Week number of the year, assuming weeks start on sunday.
+ * The first Sunday of January is the first day of week 1;
+ * days in the new year before this are in week 0.
+ *
+ * @param tm Normalized broken-down time.
+ * @return The week number (0 - 53).
+ */
+static int _sun_week_number(const struct posix_tm *tm)
+{
+        int first_day = (7 - _day_of_week(tm->tm_year, 0, 1)) % 7;
+        return (tm->tm_yday - first_day + 7) / 7;
+}
+
+/**
+ * Week number of the year, assuming weeks start on monday.
+ * If the week containing January 1st has four or more days in the new year,
+ * then it is considered week 1. Otherwise, it is the last week of the previous
+ * year, and the next week is week 1. Both January 4th and the first Thursday
+ * of January are always in week 1.
+ *
+ * @param tm Normalized broken-down time.
+ * @return The week number (1 - 53).
+ */
+static int _iso_week_number(const struct posix_tm *tm)
+{
+        int day = tm->tm_yday - _wbyear_offset(tm->tm_year);
+        if (day < 0) {
+                /* Last week of previous year. */
+                return 53;
+        }
+        if (day > 364 + _is_leap_year(tm->tm_year)) {
+                /* First week of next year. */
+                return 1;
+        }
+        /* All the other days give correct answer. */
+        return (day / 7 + 1);
+}
+
+/**
+ * Week number of the year, assuming weeks start on monday.
+ * The first Monday of January is the first day of week 1;
+ * days in the new year before this are in week 0. 
+ *
+ * @param tm Normalized broken-down time.
+ * @return The week number (0 - 53).
+ */
+static int _mon_week_number(const struct posix_tm *tm)
+{
+        int first_day = (1 - _day_of_week(tm->tm_year, 0, 1)) % 7;
+        return (tm->tm_yday - first_day + 7) / 7;
+}
+
 /******************************************************************************/
 
@@ -311 +412 @@
 
 /**
+ * Calculate the difference between two times, in seconds.
+ * 
+ * @param time1 First time.
+ * @param time0 Second time.
+ * @return Time in seconds.
+ */
+double posix_difftime(time_t time1, time_t time0)
+{
+        return (double) (time1 - time0);
+}
+
+/**
+ * This function first normalizes the provided broken-down time
+ * (moves all values to their proper bounds) and then tries to
+ * calculate the appropriate time_t representation.
+ *
+ * @param tm Broken-down time.
+ * @return time_t representation of the time, undefined value on overflow.
+ */
+time_t posix_mktime(struct posix_tm *tm)
+{
+        // TODO: take DST flag into account
+        // TODO: detect overflow
+
+        _normalize_time(tm, 0);
+        return _secs_since_epoch(tm);
+}
+
+/**
+ * Converts a time value to a broken-down UTC time.
+ *
+ * @param timer Time to convert.
+ * @return Normalized broken-down time in UTC, NULL on overflow.
+ */
+struct posix_tm *posix_gmtime(const time_t *timer)
+{
+        assert(timer != NULL);
+
+        static struct posix_tm result;
+        return posix_gmtime_r(timer, &result);
+}
+
+/**
  * Converts a time value to a broken-down UTC time.
  * 
@@ -317 +461 @@
  * @return Value of result on success, NULL on overflow.
  */
-struct tm *posix_gmtime_r(const time_t *restrict timer,
-    struct tm *restrict result)
+struct posix_tm *posix_gmtime_r(const time_t *restrict timer,
+    struct posix_tm *restrict result)
 {
         assert(timer != NULL);
@@ -341 +485 @@
 /**
  * Converts a time value to a broken-down local time.
+ *
+ * @param timer Time to convert.
+ * @return Normalized broken-down time in local timezone, NULL on overflow.
+ */
+struct posix_tm *posix_localtime(const time_t *timer)
+{
+        static struct posix_tm result;
+        return posix_localtime_r(timer, &result);
+}
+
+/**
+ * Converts a time value to a broken-down local time.
  * 
  * @param timer Time to convert.
@@ -346 +502 @@
  * @return Value of result on success, NULL on overflow.
  */
-struct tm *posix_localtime_r(const time_t *restrict timer,
-    struct tm *restrict result)
+struct posix_tm *posix_localtime_r(const time_t *restrict timer,
+    struct posix_tm *restrict result)
 {
         // TODO: deal with timezone
         // currently assumes system and all times are in GMT
         return posix_gmtime_r(timer, result);
+}
+
+/**
+ * Converts broken-down time to a string in format
+ * "Sun Jan 1 00:00:00 1970\n". (Obsolete)
+ *
+ * @param timeptr Broken-down time structure.
+ * @return Pointer to a statically allocated string.
+ */
+char *posix_asctime(const struct posix_tm *timeptr)
+{
+        static char buf[ASCTIME_BUF_LEN];
+        return posix_asctime_r(timeptr, buf);
 }
 
@@ -363 +532 @@
  * @return Value of buf.
  */
-char *posix_asctime_r(const struct tm *restrict timeptr,
+char *posix_asctime_r(const struct posix_tm *restrict timeptr,
     char *restrict buf)
 {
@@ -388 +557 @@
 
 /**
+ * Equivalent to asctime(localtime(clock)).
+ * 
+ * @param timer Time to convert.
+ * @return Pointer to a statically allocated string holding the date.
+ */
+char *posix_ctime(const time_t *timer)
+{
+        struct posix_tm *loctime = posix_localtime(timer);
+        if (loctime == NULL) {
+                return NULL;
+        }
+        return posix_asctime(loctime);
+}
+
+/**
  * Reentrant variant of ctime().
  * 
@@ -397 +581 @@
 char *posix_ctime_r(const time_t *timer, char *buf)
 {
-        struct tm loctime;
+        struct posix_tm loctime;
         if (posix_localtime_r(timer, &loctime) == NULL) {
                 return NULL;
         }
         return posix_asctime_r(&loctime, buf);
+}
+
+/**
+ * Convert time and date to a string, based on a specified format and
+ * current locale.
+ * 
+ * @param s Buffer to write string to.
+ * @param maxsize Size of the buffer.
+ * @param format Format of the output.
+ * @param tm Broken-down time to format.
+ * @return Number of bytes written.
+ */
+size_t posix_strftime(char *restrict s, size_t maxsize,
+    const char *restrict format, const struct posix_tm *restrict tm)
+{
+        assert(s != NULL);
+        assert(format != NULL);
+        assert(tm != NULL);
+
+        // TODO: use locale
+        static const char *wday_abbr[] = {
+                "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
+        };
+        static const char *wday[] = {
+                "Sunday", "Monday", "Tuesday", "Wednesday",
+                "Thursday", "Friday", "Saturday"
+        };
+        static const char *mon_abbr[] = {
+                "Jan", "Feb", "Mar", "Apr", "May", "Jun",
+                "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
+        };
+        static const char *mon[] = {
+                "January", "February", "March", "April", "May", "June", "July",
+                "August", "September", "October", "November", "December"
+        };
+        
+        if (maxsize < 1) {
+                return 0;
+        }
+        
+        char *ptr = s;
+        size_t consumed;
+        size_t remaining = maxsize;
+        
+        #define append(...) { \
+                /* FIXME: this requires POSIX-correct snprintf */ \
+                /*        otherwise it won't work with non-ascii chars */ \
+                consumed = snprintf(ptr, remaining, __VA_ARGS__); \
+                if (consumed >= remaining) { \
+                        return 0; \
+                } \
+                ptr += consumed; \
+                remaining -= consumed; \
+        }
+        
+        #define recurse(fmt) { \
+                consumed = posix_strftime(ptr, remaining, fmt, tm); \
+                if (consumed == 0) { \
+                        return 0; \
+                } \
+                ptr += consumed; \
+                remaining -= consumed; \
+        }
+        
+        #define TO_12H(hour) (((hour) > 12) ? ((hour) - 12) : \
+            (((hour) == 0) ? 12 : (hour)))
+        
+        while (*format != '\0') {
+                if (*format != '%') {
+                        append("%c", *format);
+                        format++;
+                        continue;
+                }
+                
+                format++;
+                if (*format == '0' || *format == '+') {
+                        // TODO: padding
+                        format++;
+                }
+                while (isdigit(*format)) {
+                        // TODO: padding
+                        format++;
+                }
+                if (*format == 'O' || *format == 'E') {
+                        // TODO: locale's alternative format
+                        format++;
+                }
+                
+                switch (*format) {
+                case 'a':
+                        append("%s", wday_abbr[tm->tm_wday]); break;
+                case 'A':
+                        append("%s", wday[tm->tm_wday]); break;
+                case 'b':
+                        append("%s", mon_abbr[tm->tm_mon]); break;
+                case 'B':
+                        append("%s", mon[tm->tm_mon]); break;
+                case 'c':
+                        // TODO: locale-specific datetime format
+                        recurse("%Y-%m-%d %H:%M:%S"); break;
+                case 'C':
+                        append("%02d", (1900 + tm->tm_year) / 100); break;
+                case 'd':
+                        append("%02d", tm->tm_mday); break;
+                case 'D':
+                        recurse("%m/%d/%y"); break;
+                case 'e':
+                        append("%2d", tm->tm_mday); break;
+                case 'F':
+                        recurse("%+4Y-%m-%d"); break;
+                case 'g':
+                        append("%02d", _wbyear(tm) % 100); break;
+                case 'G':
+                        append("%d", _wbyear(tm)); break;
+                case 'h':
+                        recurse("%b"); break;
+                case 'H':
+                        append("%02d", tm->tm_hour); break;
+                case 'I':
+                        append("%02d", TO_12H(tm->tm_hour)); break;
+                case 'j':
+                        append("%03d", tm->tm_yday); break;
+                case 'k':
+                        append("%2d", tm->tm_hour); break;
+                case 'l':
+                        append("%2d", TO_12H(tm->tm_hour)); break;
+                case 'm':
+                        append("%02d", tm->tm_mon); break;
+                case 'M':
+                        append("%02d", tm->tm_min); break;
+                case 'n':
+                        append("\n"); break;
+                case 'p':
+                        append("%s", tm->tm_hour < 12 ? "AM" : "PM"); break;
+                case 'P':
+                        append("%s", tm->tm_hour < 12 ? "am" : "PM"); break;
+                case 'r':
+                        recurse("%I:%M:%S %p"); break;
+                case 'R':
+                        recurse("%H:%M"); break;
+                case 's':
+                        append("%ld", _secs_since_epoch(tm)); break;
+                case 'S':
+                        append("%02d", tm->tm_sec); break;
+                case 't':
+                        append("\t"); break;
+                case 'T':
+                        recurse("%H:%M:%S"); break;
+                case 'u':
+                        append("%d", (tm->tm_wday == 0) ? 7 : tm->tm_wday); break;
+                case 'U':
+                        append("%02d", _sun_week_number(tm)); break;
+                case 'V':
+                        append("%02d", _iso_week_number(tm)); break;
+                case 'w':
+                        append("%d", tm->tm_wday); break;
+                case 'W':
+                        append("%02d", _mon_week_number(tm)); break;
+                case 'x':
+                        // TODO: locale-specific date format
+                        recurse("%Y-%m-%d"); break;
+                case 'X':
+                        // TODO: locale-specific time format
+                        recurse("%H:%M:%S"); break;
+                case 'y':
+                        append("%02d", tm->tm_year % 100); break;
+                case 'Y':
+                        append("%d", 1900 + tm->tm_year); break;
+                case 'z':
+                        // TODO: timezone
+                        break;
+                case 'Z':
+                        // TODO: timezone
+                        break;
+                case '%':
+                        append("%%");
+                        break;
+                default:
+                        /* Invalid specifier, print verbatim. */
+                        while (*format != '%') {
+                                format--;
+                        }
+                        append("%%");
+                        break;
+                }
+                format++;
+        }
+        
+        #undef append
+        #undef recurse
+        
+        return maxsize - remaining;
 }
 
@@ -518 +894 @@
         stats_task_t *task_stats = stats_get_task(task_get_id());
         if (task_stats) {
-                total_cycles = (posix_clock_t) (task_stats->kcycles +
-                    task_stats->ucycles);
+                total_cycles = (posix_clock_t) (task_stats->kcycles + task_stats->ucycles);
                 free(task_stats);
                 task_stats = 0;