fix #469

CE-Programming · Jan 17, 2024 · 6b98f49 · 6b98f49
1 parent 9cde264
commit 6b98f49
Show file tree

Hide file tree

Showing 4 changed files with 27 additions and 67 deletions.
diff --git a/src/libc/gmtime.c b/src/libc/gmtime.c
@@ -9,13 +9,16 @@
 #define SECS_PER_YEAR  (365UL * SECS_PER_DAY)
 #define SECS_PER_LEAP  (SECS_PER_YEAR + SECS_PER_DAY)
 
-extern bool __isleap(int year);
-
-static bool istmleap(int year)
+static bool istmleap(unsigned int year)
 {
     year += 1900;
 
-    return __isleap(year);
+    if (year % 100 == 0)
+    {
+        return year % 400 == 0;
+    }
+
+    return year % 4 == 0;
 }
 
 struct tm *gmtime(const time_t *tp)
@@ -28,16 +31,16 @@ struct tm *gmtime(const time_t *tp)
     time_t secs_this_year;
     time_t t = *tp;
 
-    tm2.tm_sec  = 0;
-    tm2.tm_min  = 0;
+    tm2.tm_sec = 0;
+    tm2.tm_min = 0;
     tm2.tm_hour = 0;
     tm2.tm_mday = 1;
-    tm2.tm_mon  = 0;
+    tm2.tm_mon = 0;
     tm2.tm_year = 70;
-    tm2.tm_wday = (t / SECS_PER_DAY + 4 ) % 7;
+    tm2.tm_wday = (t / SECS_PER_DAY + 4) % 7;
     tm2.tm_isdst = -1;
 
-    while (t >= (secs_this_year = istmleap(tm2.tm_year) ? SECS_PER_LEAP : SECS_PER_YEAR ))
+    while (t >= (secs_this_year = istmleap(tm2.tm_year) ? SECS_PER_LEAP : SECS_PER_YEAR))
     {
         t -= secs_this_year;
         tm2.tm_year++;
@@ -50,6 +53,7 @@ struct tm *gmtime(const time_t *tp)
 
     tm2.tm_yday = t / SECS_PER_DAY;
 
+    dpm[1] = 28;
     if (istmleap(tm2.tm_year))
     {
         dpm[1] = 29;
@@ -60,8 +64,6 @@ struct tm *gmtime(const time_t *tp)
         t -= dpm[tm2.tm_mon++] * SECS_PER_DAY;
     }
 
-    dpm[1] = 28;
-
     while (t >= SECS_PER_DAY)
     {
         t -= SECS_PER_DAY;

diff --git a/src/libc/isleap.c b/src/libc/isleap.c
diff --git a/src/libc/mktime.c b/src/libc/mktime.c
@@ -2,48 +2,20 @@
 #include <time.h>
 #include <stdint.h>
 
-#define SECS_PER_DAY   86400UL
-#define SECS_PER_HOUR  3600UL
-#define SECS_PER_MIN   60UL
-#define DAYS_PER_YEAR  365UL
-
-extern bool __isleap(int year);
+#define SECS_PER_DAY   86400u
+#define SECS_PER_HOUR  3600u
+#define SECS_PER_MIN   60u
 
 time_t mktime(struct tm *tp)
 {
-    static const unsigned int dpmt[] =
-    {
-        0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
-    };
-    unsigned int i;
-    time_t days;
-
-    if (tp->tm_year < (1970 - 1900))
-    {
-        return -1L;
-    }
-
-    days = (tp->tm_year - (1970 - 1900)) * DAYS_PER_YEAR;
-
-    for (i = 1970; i < (unsigned int)tp->tm_year + 1900; ++i)
-    {
-        if (__isleap(i))
-        {
-            days++;
-        }
-    }
-
-    days += dpmt[tp->tm_mon];
-    if (__isleap(tp->tm_year))
-    {
-        days++;
-    }
-
-    days += tp->tm_mday - 1;
-
-    days *= SECS_PER_DAY;
-
-    days += (tp->tm_hour * SECS_PER_HOUR) + (tp->tm_min * SECS_PER_MIN) + tp->tm_sec;
-
-    return days;
+    static const int yday[] = { -1, 30, 58, 89, 119, 150, 180, 211, 242, 272, 303, 333 };
+
+    return
+        tp->tm_sec +
+        tp->tm_min * SECS_PER_MIN +
+        tp->tm_hour * SECS_PER_HOUR +
+        (yday[tp->tm_mon] + tp->tm_mday) * SECS_PER_DAY +
+        (tp->tm_year - 70) * 31536000 + ((tp->tm_year - 69) / 4) * SECS_PER_DAY -
+        ((tp->tm_year - 1) / 100) * SECS_PER_DAY + ((tp->tm_year + 299) / 400) * SECS_PER_DAY;
 }
+
diff --git a/src/libc/time.c b/src/libc/time.c
@@ -13,13 +13,11 @@ time_t time(time_t *timer)
     boot_GetDate(&day, &month, &year);
     boot_GetTime(&sec, &min, &hrs);
 
-    month--;
-
     tm2.tm_sec = sec;
     tm2.tm_min = min;
     tm2.tm_hour = hrs;
     tm2.tm_mday = day;
-    tm2.tm_mon = month;
+    tm2.tm_mon = month - 1;
     tm2.tm_year = (unsigned int)year - 1900;
 
     res = mktime(&tm2);