diff options
Diffstat (limited to 'src/main/c/simple_time.c')
| -rw-r--r-- | src/main/c/simple_time.c | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/src/main/c/simple_time.c b/src/main/c/simple_time.c new file mode 100644 index 00000000..2e579922 --- /dev/null +++ b/src/main/c/simple_time.c @@ -0,0 +1,61 @@ +#define _POSIX_C_SOURCE 200809L +#include <time.h> +#include <stdint.h> +#include <errno.h> + +// Fixed-width bridge; no native struct layout or retained Simple pointers. +static int64_t clock_value(clockid_t clock, int64_t scale) { + struct timespec t; + if (clock_gettime(clock,&t)) return -1; + if (t.tv_sec>INT64_MAX/scale || t.tv_sec<INT64_MIN/scale) { + errno=EOVERFLOW; return -1; + } + int64_t base=(int64_t)t.tv_sec*scale; + int64_t fraction=t.tv_nsec/(1000000000/scale); + if (base>INT64_MAX-fraction) { errno=EOVERFLOW; return -1; } + return base+fraction; +} +int64_t simple_time_now(void) { return clock_value(CLOCK_REALTIME,1000); } +int64_t simple_time_mono(void) { return clock_value(CLOCK_MONOTONIC,1000); } +int64_t simple_time_nano(void) { return clock_value(CLOCK_MONOTONIC,1000000000); } +int32_t simple_time_sleep(int64_t ms, int32_t absolute) { + if (ms<0) { errno=EINVAL; return -1; } + struct timespec t={ms/1000,(ms%1000)*1000000}; + int result; + if (!absolute) { + // Retry the remaining duration after signals; no busy waiting. + do { result=nanosleep(&t,&t); } while (result && errno==EINTR); + return result; + } + do { result=clock_nanosleep(CLOCK_MONOTONIC,TIMER_ABSTIME,&t,NULL); } while (result==EINTR); + if (result) { errno=result; return -1; } + return 0; +} +static int leap(int y) { return y%4==0 && (y%100!=0 || y%400==0); } +static int local_fields(int64_t ms, struct tm *local, struct tm *utc) { + tzset(); + int64_t sec=ms/1000; + if (ms%1000<0) --sec; + time_t t=(time_t)sec; + if ((int64_t)t!=sec || !localtime_r(&t,local) || !gmtime_r(&t,utc)) return -1; + if (local->tm_year < -1899 || local->tm_year > 8099) { errno=EOVERFLOW; return -1; } + return 0; +} +int32_t simple_time_local(int64_t ms, int64_t *out) { + struct tm t,u; + if (local_fields(ms,&t,&u)) return -1; + int days=t.tm_yday-u.tm_yday; + if (t.tm_year>u.tm_year) days+=365+leap(u.tm_year+1900); + if (t.tm_year<u.tm_year) days-=365+leap(t.tm_year+1900); + int offset=days*86400+(t.tm_hour-u.tm_hour)*3600+(t.tm_min-u.tm_min)*60+t.tm_sec-u.tm_sec; + out[0]=t.tm_year+1900; out[1]=t.tm_mon+1; out[2]=t.tm_mday; + out[3]=t.tm_hour; out[4]=t.tm_min; out[5]=t.tm_sec; + out[6]=(ms%1000+1000)%1000; out[7]=t.tm_wday; + out[8]=offset; out[9]=t.tm_isdst>0; + return 0; +} +int32_t simple_time_zone(int64_t ms, char *out, uint32_t capacity) { + struct tm t,u; + if (!capacity || local_fields(ms,&t,&u)) return -1; + return (int32_t)strftime(out,capacity,"%Z",&t); +} |
