diff options
| -rw-r--r-- | fs/fat/misc.c | 57 |
1 files changed, 15 insertions, 42 deletions
diff --git a/fs/fat/misc.c b/fs/fat/misc.c index 0f55f5cb732f..d3da05f26465 100644 --- a/fs/fat/misc.c +++ b/fs/fat/misc.c @@ -9,6 +9,7 @@ #include <linux/module.h> #include <linux/fs.h> #include <linux/buffer_head.h> +#include <linux/time.h> #include "fat.h" /* @@ -157,10 +158,6 @@ extern struct timezone sys_tz; #define SECS_PER_MIN 60 #define SECS_PER_HOUR (60 * 60) #define SECS_PER_DAY (SECS_PER_HOUR * 24) -#define UNIX_SECS_1980 315532800L -#if BITS_PER_LONG == 64 -#define UNIX_SECS_2108 4354819200L -#endif /* days between 1.1.70 and 1.1.80 (2 leap days) */ #define DAYS_DELTA (365 * 10 + 2) /* 120 (2100 - 1980) isn't leap year */ @@ -213,58 +210,35 @@ void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts, void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts, __le16 *time, __le16 *date, u8 *time_cs) { - time_t second = ts->tv_sec; - time_t day, leap_day, month, year; + struct tm tm; + time_to_tm(ts->tv_sec, sbi->options.tz_utc ? 0 : + -sys_tz.tz_minuteswest * 60, &tm); - if (!sbi->options.tz_utc) - second -= sys_tz.tz_minuteswest * SECS_PER_MIN; - - /* Jan 1 GMT 00:00:00 1980. But what about another time zone? */ - if (second < UNIX_SECS_1980) { + /* FAT can only support year between 1980 to 2107 */ + if (tm.tm_year < 1980 - 1900) { *time = 0; *date = cpu_to_le16((0 << 9) | (1 << 5) | 1); if (time_cs) *time_cs = 0; return; } -#if BITS_PER_LONG == 64 - if (second >= UNIX_SECS_2108) { + if (tm.tm_year > 2107 - 1900) { *time = cpu_to_le16((23 << 11) | (59 << 5) | 29); *date = cpu_to_le16((127 << 9) | (12 << 5) | 31); if (time_cs) *time_cs = 199; return; } -#endif - day = second / SECS_PER_DAY - DAYS_DELTA; - year = day / 365; - leap_day = (year + 3) / 4; - if (year > YEAR_2100) /* 2100 isn't leap year */ - leap_day--; - if (year * 365 + leap_day > day) - year--; - leap_day = (year + 3) / 4; - if (year > YEAR_2100) /* 2100 isn't leap year */ - leap_day--; - day -= year * 365 + leap_day; - - if (IS_LEAP_YEAR(year) && day == days_in_year[3]) { - month = 2; - } else { - if (IS_LEAP_YEAR(year) && day > days_in_year[3]) - day--; - for (month = 1; month < 12; month++) { - if (days_in_year[month + 1] > day) - break; - } - } - day -= days_in_year[month]; + /* from 1900 -> from 1980 */ + tm.tm_year -= 80; + /* 0~11 -> 1~12 */ + tm.tm_mon++; + /* 0~59 -> 0~29(2sec counts) */ + tm.tm_sec >>= 1; - *time = cpu_to_le16(((second / SECS_PER_HOUR) % 24) << 11 - | ((second / SECS_PER_MIN) % 60) << 5 - | (second % SECS_PER_MIN) >> 1); - *date = cpu_to_le16((year << 9) | (month << 5) | (day + 1)); + *time = cpu_to_le16(tm.tm_hour << 11 | tm.tm_min << 5 | tm.tm_sec); + *date = cpu_to_le16(tm.tm_year << 9 | tm.tm_mon << 5 | tm.tm_mday); if (time_cs) *time_cs = (ts->tv_sec & 1) * 100 + ts->tv_nsec / 10000000; } @@ -285,4 +259,3 @@ int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs) } return err; } - |