1 //! time implementation for Redox, following http://pubs.opengroup.org/onlinepubs/7908799/xsh/time.h.html 2 3 use core::convert::{TryFrom, TryInto}; 4 5 use crate::{ 6 header::errno::EOVERFLOW, 7 platform::{self, types::*, Pal, Sys}, 8 }; 9 10 pub use self::constants::*; 11 12 pub mod constants; 13 mod strftime; 14 15 #[repr(C)] 16 #[derive(Default)] 17 pub struct timespec { 18 pub tv_sec: time_t, 19 pub tv_nsec: c_long, 20 } 21 22 #[cfg(target_os = "redox")] 23 impl<'a> From<&'a timespec> for syscall::TimeSpec { 24 fn from(tp: ×pec) -> Self { 25 Self { 26 tv_sec: tp.tv_sec as i64, 27 tv_nsec: tp.tv_nsec as i32, 28 } 29 } 30 } 31 32 #[repr(C)] 33 pub struct tm { 34 pub tm_sec: c_int, 35 pub tm_min: c_int, 36 pub tm_hour: c_int, 37 pub tm_mday: c_int, 38 pub tm_mon: c_int, 39 pub tm_year: c_int, 40 pub tm_wday: c_int, 41 pub tm_yday: c_int, 42 pub tm_isdst: c_int, 43 pub tm_gmtoff: c_long, 44 pub tm_zone: *const c_char, 45 } 46 47 unsafe impl Sync for tm {} 48 49 // The C Standard says that localtime and gmtime return the same pointer. 50 static mut TM: tm = tm { 51 tm_sec: 0, 52 tm_min: 0, 53 tm_hour: 0, 54 tm_mday: 0, 55 tm_mon: 0, 56 tm_year: 0, 57 tm_wday: 0, 58 tm_yday: 0, 59 tm_isdst: 0, 60 tm_gmtoff: 0, 61 tm_zone: UTC, 62 }; 63 64 // The C Standard says that ctime and asctime return the same pointer. 65 static mut ASCTIME: [c_char; 26] = [0; 26]; 66 67 #[repr(C)] 68 pub struct itimerspec { 69 pub it_interval: timespec, 70 pub it_value: timespec, 71 } 72 73 pub struct sigevent; 74 75 #[no_mangle] 76 pub unsafe extern "C" fn asctime(timeptr: *const tm) -> *mut c_char { 77 asctime_r(timeptr, ASCTIME.as_mut_ptr().cast()) 78 } 79 80 #[no_mangle] 81 pub unsafe extern "C" fn asctime_r(tm: *const tm, buf: *mut c_char) -> *mut c_char { 82 let tm_sec = (*tm).tm_sec; 83 let tm_min = (*tm).tm_min; 84 let tm_hour = (*tm).tm_hour; 85 let tm_mday = (*tm).tm_mday; 86 let tm_mon = (*tm).tm_mon; 87 let tm_year = (*tm).tm_year; 88 let tm_wday = (*tm).tm_wday; 89 90 /* Panic when we run into undefined behavior. 91 * 92 * POSIX says (since issue 7) that asctime()/asctime_r() cause UB 93 * when the tm member values would cause out-of-bounds array access 94 * or overflow the output buffer. This contrasts with ISO C11+, 95 * which specifies UB for any tm members being outside their normal 96 * ranges. While POSIX explicitly defers to the C standard in case 97 * of contradictions, the assertions below follow the interpretation 98 * that POSIX simply defines some of C's undefined behavior, rather 99 * than conflict with the ISO standard. 100 * 101 * Note that C's "%.2d" formatting, unlike Rust's "{:02}" 102 * formatting, does not count a minus sign against the two digits to 103 * print, meaning that we must reject all negative values for 104 * seconds, minutes and hours. However, C's "%3d" (for day-of-month) 105 * is similar to Rust's "{:3}". 106 * 107 * To avoid year overflow problems (in Rust, where numeric overflow 108 * is considered an error), we subtract 1900 from the endpoints, 109 * rather than adding to the tm_year value. POSIX' requirement that 110 * tm_year be at most {INT_MAX}-1990 is satisfied for all legal 111 * values of {INT_MAX} through the max-4-digit requirement on the 112 * year. 113 * 114 * The tm_mon and tm_wday fields are used for array access and thus 115 * will already cause a panic in Rust code when out of range. 116 * However, using the assertions below allows a consistent error 117 * message for all fields. */ 118 const OUT_OF_RANGE_MESSAGE: &str = "tm member out of range"; 119 120 assert!(0 <= tm_sec && tm_sec <= 99, "{}", OUT_OF_RANGE_MESSAGE); 121 assert!(0 <= tm_min && tm_min <= 99, "{}", OUT_OF_RANGE_MESSAGE); 122 assert!(0 <= tm_hour && tm_hour <= 99, "{}", OUT_OF_RANGE_MESSAGE); 123 assert!(-99 <= tm_mday && tm_mday <= 999, "{}", OUT_OF_RANGE_MESSAGE); 124 assert!(0 <= tm_mon && tm_mon <= 11, "{}", OUT_OF_RANGE_MESSAGE); 125 assert!( 126 -999 - 1900 <= tm_year && tm_year <= 9999 - 1900, 127 "{}", 128 OUT_OF_RANGE_MESSAGE 129 ); 130 assert!(0 <= tm_wday && tm_wday <= 6, "{}", OUT_OF_RANGE_MESSAGE); 131 132 // At this point, we can safely use the values as given. 133 let write_result = core::fmt::write( 134 // buf may be either `*mut u8` or `*mut i8` 135 &mut platform::UnsafeStringWriter(buf.cast()), 136 format_args!( 137 "{:.3} {:.3}{:3} {:02}:{:02}:{:02} {}\n", 138 DAY_NAMES[usize::try_from(tm_wday).unwrap()], 139 MON_NAMES[usize::try_from(tm_mon).unwrap()], 140 tm_mday, 141 tm_hour, 142 tm_min, 143 tm_sec, 144 1900 + tm_year 145 ), 146 ); 147 match write_result { 148 Ok(_) => buf, 149 Err(_) => { 150 /* asctime()/asctime_r() or the equivalent sprintf() call 151 * have no defined errno setting */ 152 core::ptr::null_mut() 153 } 154 } 155 } 156 157 #[no_mangle] 158 pub extern "C" fn clock() -> clock_t { 159 let mut ts = core::mem::MaybeUninit::<timespec>::uninit(); 160 161 if clock_gettime(CLOCK_PROCESS_CPUTIME_ID, ts.as_mut_ptr()) != 0 { 162 return -1; 163 } 164 let ts = unsafe { ts.assume_init() }; 165 166 let clocks = 167 ts.tv_sec * CLOCKS_PER_SEC as i64 + (ts.tv_nsec / (1_000_000_000 / CLOCKS_PER_SEC)) as i64; 168 match clock_t::try_from(clocks) { 169 Ok(ok) => ok, 170 Err(_err) => -1, 171 } 172 } 173 174 // #[no_mangle] 175 pub extern "C" fn clock_getres(clock_id: clockid_t, res: *mut timespec) -> c_int { 176 unimplemented!(); 177 } 178 179 #[no_mangle] 180 pub extern "C" fn clock_gettime(clock_id: clockid_t, tp: *mut timespec) -> c_int { 181 Sys::clock_gettime(clock_id, tp) 182 } 183 184 // #[no_mangle] 185 pub extern "C" fn clock_settime(clock_id: clockid_t, tp: *const timespec) -> c_int { 186 unimplemented!(); 187 } 188 189 #[no_mangle] 190 pub unsafe extern "C" fn ctime(clock: *const time_t) -> *mut c_char { 191 asctime(localtime(clock)) 192 } 193 194 #[no_mangle] 195 pub unsafe extern "C" fn ctime_r(clock: *const time_t, buf: *mut c_char) -> *mut c_char { 196 // Using MaybeUninit<tm> seems to cause a panic during the build process 197 let mut tm1 = tm { 198 tm_sec: 0, 199 tm_min: 0, 200 tm_hour: 0, 201 tm_mday: 0, 202 tm_mon: 0, 203 tm_year: 0, 204 tm_wday: 0, 205 tm_yday: 0, 206 tm_isdst: 0, 207 tm_gmtoff: 0, 208 tm_zone: core::ptr::null_mut(), 209 }; 210 localtime_r(clock, &mut tm1); 211 asctime_r(&tm1, buf) 212 } 213 214 #[no_mangle] 215 pub extern "C" fn difftime(time1: time_t, time0: time_t) -> c_double { 216 (time1 - time0) as c_double 217 } 218 219 // #[no_mangle] 220 pub extern "C" fn getdate(string: *const c_char) -> tm { 221 unimplemented!(); 222 } 223 224 #[no_mangle] 225 pub unsafe extern "C" fn gmtime(timer: *const time_t) -> *mut tm { 226 gmtime_r(timer, &mut TM) 227 } 228 229 const MONTH_DAYS: [[c_int; 12]; 2] = [ 230 // Non-leap years: 231 [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31], 232 // Leap years: 233 [31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31], 234 ]; 235 236 #[inline(always)] 237 fn leap_year(year: c_int) -> bool { 238 year % 4 == 0 && (year % 100 != 0 || year % 400 == 0) 239 } 240 241 #[no_mangle] 242 pub unsafe extern "C" fn gmtime_r(clock: *const time_t, result: *mut tm) -> *mut tm { 243 /* For the details of the algorithm used here, see 244 * http://howardhinnant.github.io/date_algorithms.html#civil_from_days 245 * Note that we need 0-based months here, though. 246 * Overall, this implementation should generate correct results as 247 * long as the tm_year value will fit in a c_int. */ 248 const SECS_PER_DAY: time_t = 24 * 60 * 60; 249 const DAYS_PER_ERA: time_t = 146097; 250 251 let unix_secs = *clock; 252 253 /* Day number here is possibly negative, remainder will always be 254 * nonnegative when using Euclidean division */ 255 let unix_days: time_t = unix_secs.div_euclid(SECS_PER_DAY); 256 257 /* In range [0, 86399]. Needs a u32 since this is larger (at least 258 * theoretically) than the guaranteed range of c_int */ 259 let secs_of_day: u32 = unix_secs.rem_euclid(SECS_PER_DAY).try_into().unwrap(); 260 261 /* Shift origin from 1970-01-01 to 0000-03-01 and find out where we 262 * are in terms of 400-year eras since then */ 263 let days_since_origin = unix_days + 719468; 264 let era = days_since_origin.div_euclid(DAYS_PER_ERA); 265 let day_of_era = days_since_origin.rem_euclid(DAYS_PER_ERA); 266 let year_of_era = 267 (day_of_era - day_of_era / 1460 + day_of_era / 36524 - day_of_era / 146096) / 365; 268 269 /* "transformed" here refers to dates in a calendar where years 270 * start on March 1 */ 271 let year_transformed = year_of_era + 400 * era; // retain large range, don't convert to c_int yet 272 let day_of_year_transformed: c_int = (day_of_era 273 - (365 * year_of_era + year_of_era / 4 - year_of_era / 100)) 274 .try_into() 275 .unwrap(); 276 let month_transformed: c_int = (5 * day_of_year_transformed + 2) / 153; 277 278 // Convert back to calendar with year starting on January 1 279 let month: c_int = (month_transformed + 2) % 12; // adapted to 0-based months 280 let year: time_t = if month < 2 { 281 year_transformed + 1 282 } else { 283 year_transformed 284 }; 285 286 /* Subtract 1900 *before* converting down to c_int in order to 287 * maximize the range of input timestamps that will succeed */ 288 match c_int::try_from(year - 1900) { 289 Ok(year_less_1900) => { 290 let mday: c_int = (day_of_year_transformed - (153 * month_transformed + 2) / 5 + 1) 291 .try_into() 292 .unwrap(); 293 294 /* 1970-01-01 was a Thursday. Again, Euclidean division is 295 * used to ensure a nonnegative remainder (range [0, 6]). */ 296 let wday: c_int = ((unix_days + 4).rem_euclid(7)).try_into().unwrap(); 297 298 /* Yes, duplicated code for now (to work on non-c_int-values 299 * so that we are not constrained by the subtraction of 300 * 1900) */ 301 let is_leap_year: bool = year % 4 == 0 && (year % 100 != 0 || year % 400 == 0); 302 303 /* For dates in January or February, we use the fact that 304 * January 1 is always 306 days after March 1 in the 305 * previous year. */ 306 let yday: c_int = if month < 2 { 307 day_of_year_transformed - 306 308 } else { 309 day_of_year_transformed + if is_leap_year { 60 } else { 59 } 310 }; 311 312 let hour: c_int = (secs_of_day / (60 * 60)).try_into().unwrap(); 313 let min: c_int = ((secs_of_day / 60) % 60).try_into().unwrap(); 314 let sec: c_int = (secs_of_day % 60).try_into().unwrap(); 315 316 *result = tm { 317 tm_sec: sec, 318 tm_min: min, 319 tm_hour: hour, 320 tm_mday: mday, 321 tm_mon: month, 322 tm_year: year_less_1900, 323 tm_wday: wday, 324 tm_yday: yday, 325 tm_isdst: 0, 326 tm_gmtoff: 0, 327 tm_zone: UTC, 328 }; 329 330 result 331 } 332 Err(_) => { 333 platform::errno = EOVERFLOW; 334 core::ptr::null_mut() 335 } 336 } 337 } 338 339 #[no_mangle] 340 pub unsafe extern "C" fn localtime(clock: *const time_t) -> *mut tm { 341 localtime_r(clock, &mut TM) 342 } 343 344 #[no_mangle] 345 pub unsafe extern "C" fn localtime_r(clock: *const time_t, t: *mut tm) -> *mut tm { 346 // TODO: Change tm_isdst, tm_gmtoff, tm_zone 347 gmtime_r(clock, t) 348 } 349 350 #[no_mangle] 351 pub unsafe extern "C" fn mktime(t: *mut tm) -> time_t { 352 let mut year = (*t).tm_year + 1900; 353 let mut month = (*t).tm_mon; 354 let mut day = (*t).tm_mday as i64 - 1; 355 356 let leap = if leap_year(year) { 1 } else { 0 }; 357 358 if year < 1970 { 359 day = MONTH_DAYS[if leap_year(year) { 1 } else { 0 }][(*t).tm_mon as usize] as i64 - day; 360 361 while year < 1969 { 362 year += 1; 363 day += if leap_year(year) { 366 } else { 365 }; 364 } 365 366 while month < 11 { 367 month += 1; 368 day += MONTH_DAYS[leap][month as usize] as i64; 369 } 370 371 (-(day * (60 * 60 * 24) 372 - (((*t).tm_hour as i64) * (60 * 60) + ((*t).tm_min as i64) * 60 + (*t).tm_sec as i64))) 373 as time_t 374 } else { 375 while year > 1970 { 376 year -= 1; 377 day += if leap_year(year) { 366 } else { 365 }; 378 } 379 380 while month > 0 { 381 month -= 1; 382 day += MONTH_DAYS[leap][month as usize] as i64; 383 } 384 385 (day * (60 * 60 * 24) 386 + ((*t).tm_hour as i64) * (60 * 60) 387 + ((*t).tm_min as i64) * 60 388 + (*t).tm_sec as i64) as time_t 389 } 390 } 391 392 #[no_mangle] 393 pub extern "C" fn nanosleep(rqtp: *const timespec, rmtp: *mut timespec) -> c_int { 394 Sys::nanosleep(rqtp, rmtp) 395 } 396 397 #[no_mangle] 398 pub unsafe extern "C" fn strftime( 399 s: *mut c_char, 400 maxsize: size_t, 401 format: *const c_char, 402 timeptr: *const tm, 403 ) -> size_t { 404 let ret = strftime::strftime( 405 &mut platform::StringWriter(s as *mut u8, maxsize), 406 format, 407 timeptr, 408 ); 409 if ret < maxsize { 410 ret 411 } else { 412 0 413 } 414 } 415 416 // #[no_mangle] 417 pub extern "C" fn strptime(buf: *const c_char, format: *const c_char, tm: *mut tm) -> *mut c_char { 418 unimplemented!(); 419 } 420 421 #[no_mangle] 422 pub unsafe extern "C" fn time(tloc: *mut time_t) -> time_t { 423 let mut ts = timespec::default(); 424 Sys::clock_gettime(CLOCK_REALTIME, &mut ts); 425 if !tloc.is_null() { 426 *tloc = ts.tv_sec 427 }; 428 ts.tv_sec 429 } 430 431 #[no_mangle] 432 pub unsafe extern "C" fn timelocal(tm: *mut tm) -> time_t { 433 //TODO: timezone 434 timegm(tm) 435 } 436 437 #[no_mangle] 438 pub unsafe extern "C" fn timegm(tm: *mut tm) -> time_t { 439 let mut y = (*tm).tm_year as time_t + 1900; 440 let mut m = (*tm).tm_mon as time_t + 1; 441 if m <= 2 { 442 y -= 1; 443 m += 12; 444 } 445 let d = (*tm).tm_mday as time_t; 446 let h = (*tm).tm_hour as time_t; 447 let mi = (*tm).tm_min as time_t; 448 let s = (*tm).tm_sec as time_t; 449 (365 * y + y / 4 - y / 100 + y / 400 + 3 * (m + 1) / 5 + 30 * m + d - 719561) * 86400 450 + 3600 * h 451 + 60 * mi 452 + s 453 } 454 455 // #[no_mangle] 456 pub extern "C" fn timer_create( 457 clock_id: clockid_t, 458 evp: *mut sigevent, 459 timerid: *mut timer_t, 460 ) -> c_int { 461 unimplemented!(); 462 } 463 464 // #[no_mangle] 465 pub extern "C" fn timer_delete(timerid: timer_t) -> c_int { 466 unimplemented!(); 467 } 468 469 // #[no_mangle] 470 pub extern "C" fn tzset() { 471 unimplemented!(); 472 } 473 474 // #[no_mangle] 475 pub extern "C" fn timer_settime( 476 timerid: timer_t, 477 flags: c_int, 478 value: *const itimerspec, 479 ovalue: *mut itimerspec, 480 ) -> c_int { 481 unimplemented!(); 482 } 483 484 // #[no_mangle] 485 pub extern "C" fn timer_gettime(timerid: timer_t, value: *mut itimerspec) -> c_int { 486 unimplemented!(); 487 } 488 489 // #[no_mangle] 490 pub extern "C" fn timer_getoverrun(timerid: timer_t) -> c_int { 491 unimplemented!(); 492 } 493 494 /* 495 #[no_mangle] 496 pub extern "C" fn func(args) -> c_int { 497 unimplemented!(); 498 } 499 */ 500