Add fromWinTime and deprecate unixTimeToWinTime/winTimeToUnixTime (#7641)

lib/pure/os.nim

@@ -188,7 +188,7 @@ proc getLastModificationTime*(file: string): times.Time {.rtl, extern: "nos$1".}
     var f: WIN32_FIND_DATA
     var h = findFirstFile(file, f)
     if h == -1'i32: raiseOSError(osLastError())
-    result = fromUnix(winTimeToUnixTime(rdFileTime(f.ftLastWriteTime)).int64)
+    result = fromWinTime(rdFileTime(f.ftLastWriteTime))
     findClose(h)
 
 proc getLastAccessTime*(file: string): times.Time {.rtl, extern: "nos$1".} =
@@ -201,7 +201,7 @@ proc getLastAccessTime*(file: string): times.Time {.rtl, extern: "nos$1".} =
     var f: WIN32_FIND_DATA
     var h = findFirstFile(file, f)
     if h == -1'i32: raiseOSError(osLastError())
-    result = fromUnix(winTimeToUnixTime(rdFileTime(f.ftLastAccessTime)).int64)
+    result = fromWinTime(rdFileTime(f.ftLastAccessTime))
     findClose(h)
 
 proc getCreationTime*(file: string): times.Time {.rtl, extern: "nos$1".} =
@@ -218,7 +218,7 @@ proc getCreationTime*(file: string): times.Time {.rtl, extern: "nos$1".} =
     var f: WIN32_FIND_DATA
     var h = findFirstFile(file, f)
     if h == -1'i32: raiseOSError(osLastError())
-    result = fromUnix(winTimeToUnixTime(rdFileTime(f.ftCreationTime)).int64)
+    result = fromWinTime(rdFileTime(f.ftCreationTime))
     findClose(h)
 
 proc fileNewer*(a, b: string): bool {.rtl, extern: "nos$1".} =
@@ -1512,16 +1512,14 @@ template rawToFormalFileInfo(rawInfo, path, formalInfo): untyped =
   ## 'rawInfo' is either a 'TBY_HANDLE_FILE_INFORMATION' structure on Windows,
   ## or a 'Stat' structure on posix
   when defined(Windows):
-    template toTime(e: FILETIME): untyped {.gensym.} =
-      fromUnix(winTimeToUnixTime(rdFileTime(e)).int64) # local templates default to bind semantics
     template merge(a, b): untyped = a or (b shl 32)
     formalInfo.id.device = rawInfo.dwVolumeSerialNumber
     formalInfo.id.file = merge(rawInfo.nFileIndexLow, rawInfo.nFileIndexHigh)
     formalInfo.size = merge(rawInfo.nFileSizeLow, rawInfo.nFileSizeHigh)
     formalInfo.linkCount = rawInfo.nNumberOfLinks
-    formalInfo.lastAccessTime = toTime(rawInfo.ftLastAccessTime)
+    formalInfo.lastAccessTime = fromWinTime(rdFileTime(rawInfo.ftLastAccessTime))
-    formalInfo.lastWriteTime = toTime(rawInfo.ftLastWriteTime)
+    formalInfo.lastWriteTime = fromWinTime(rdFileTime(rawInfo.ftLastWriteTime))
-    formalInfo.creationTime = toTime(rawInfo.ftCreationTime)
+    formalInfo.creationTime = fromWinTime(rdFileTime(rawInfo.ftCreationTime))
 
     # Retrieve basic permissions
     if (rawInfo.dwFileAttributes and FILE_ATTRIBUTE_READONLY) != 0'i32:

lib/pure/times.nim

@@ -374,9 +374,20 @@ proc toUnix*(t: Time): int64 {.benign, tags: [], raises: [], noSideEffect.} =
   ## Convert ``t`` to a unix timestamp (seconds since ``1970-01-01T00:00:00Z``).
   t.seconds
 
+proc fromWinTime*(win: int64): Time =
+  ## Convert a Windows file time (100-nanosecond intervals since ``1601-01-01T00:00:00Z``)
+  ## to a ``Time``.
+  let hnsecsSinceEpoch = (win - epochDiff)
+  var seconds = hnsecsSinceEpoch div rateDiff
+  var nanos = ((hnsecsSinceEpoch mod rateDiff) * 100).int
+  if nanos < 0:
+    nanos += convert(Seconds, Nanoseconds, 1)
+    seconds -= 1
+  result = initTime(seconds, nanos)
+
 proc toWinTime*(t: Time): int64 =
   ## Convert ``t`` to a Windows file time (100-nanosecond intervals since ``1601-01-01T00:00:00Z``).
-  result = t.seconds * rateDiff + epochDiff
+  result = t.seconds * rateDiff + epochDiff + t.nanoseconds div 100
 
 proc isLeapYear*(year: int): bool =
   ## Returns true if ``year`` is a leap year.
@@ -860,10 +871,7 @@ proc getTime*(): Time {.tags: [TimeEffect], benign.} =
   elif defined(windows):
     var f: FILETIME
     getSystemTimeAsFileTime(f)
-    let nanosSinceEpoch = (rdFileTime(f) - epochDiff) * 100
+    result = fromWinTime(rdFileTime(f))
-    let seconds = convert(Nanoseconds, Seconds, nanosSinceEpoch)
-    let nanos = (nanosSinceEpoch mod convert(Seconds, Nanoseconds, 1)).int
-    result = initTime(seconds, nanos)
 
 proc now*(): DateTime {.tags: [TimeEffect], benign.} =
   ## Get the current time as a  ``DateTime`` in the local timezone.
@@ -1720,14 +1728,6 @@ when not defined(JS):
   var
     clocksPerSec {.importc: "CLOCKS_PER_SEC", nodecl.}: int
 
-  proc unixTimeToWinTime*(time: CTime): int64 =
-    ## converts a UNIX `Time` (``time_t``) to a Windows file time
-    result = int64(time) * rateDiff + epochDiff
-
-  proc winTimeToUnixTime*(time: int64): CTime =
-    ## converts a Windows time to a UNIX `Time` (``time_t``)
-    result = CTime((time - epochDiff) div rateDiff)
-
   when not defined(useNimRtl):
     proc cpuTime*(): float {.rtl, extern: "nt$1", tags: [TimeEffect].} =
       ## gets time spent that the CPU spent to run the current process in
@@ -1769,6 +1769,19 @@ when defined(JS):
 
 # Deprecated procs
 
+when not defined(JS):
+  proc unixTimeToWinTime*(time: CTime): int64 {.deprecated: "Use toWinTime instead".} =
+    ## Converts a UNIX `Time` (``time_t``) to a Windows file time
+    ##
+    ## **Deprecated:** use ``toWinTime`` instead.
+    result = int64(time) * rateDiff + epochDiff
+
+  proc winTimeToUnixTime*(time: int64): CTime {.deprecated: "Use fromWinTime instead".} =
+    ## Converts a Windows time to a UNIX `Time` (``time_t``)
+    ##
+    ## **Deprecated:** use ``fromWinTime`` instead.
+    result = CTime((time - epochDiff) div rateDiff)
+
 proc initInterval*(seconds, minutes, hours, days, months,
                    years: int = 0): TimeInterval {.deprecated.} =
   ## **Deprecated since v0.18.0:** use ``initTimeInterval`` instead.

tests/stdlib/ttimes.nim

@@ -410,3 +410,10 @@ suite "ttimes":
     let day = 24.hours
     let tomorrow = now + day
     check tomorrow - now == initDuration(days = 1)
+  
+  test "fromWinTime/toWinTime":
+    check 0.fromUnix.toWinTime.fromWinTime.toUnix == 0
+    check (-1).fromWinTime.nanoseconds == convert(Seconds, Nanoseconds, 1) - 100
+    check -1.fromWinTime.toWinTime == -1
+    # One nanosecond is discarded due to differences in time resolution
+    check initTime(0, 101).toWinTime.fromWinTime.nanoseconds == 100