diff options
| -rw-r--r-- | lib/pure/random.nim | 74 | ||||
| -rw-r--r-- | lib/std/tempfiles.nim | 7 | ||||
| -rw-r--r-- | tests/stdlib/trandom.nim | 32 | ||||
| -rw-r--r-- | tests/test_nimscript.nims | 2 |
4 files changed, 95 insertions, 20 deletions
diff --git a/lib/pure/random.nim b/lib/pure/random.nim index a292386af..b8aeb86e0 100644 --- a/lib/pure/random.nim +++ b/lib/pure/random.nim @@ -108,10 +108,19 @@ when defined(js): a0: 0x69B4C98Cu32, a1: 0xFED1DD30u32) # global for backwards compatibility else: - # racy for multi-threading but good enough for now: - var state = Rand( + const DefaultRandSeed = Rand( a0: 0x69B4C98CB8530805u64, - a1: 0xFED1DD3004688D67CAu64) # global for backwards compatibility + a1: 0xFED1DD3004688D67CAu64) + + # racy for multi-threading but good enough for now: + var state = DefaultRandSeed # global for backwards compatibility + +func isValid(r: Rand): bool {.inline.} = + ## Check whether state of `r` is valid. + ## + ## In `xoroshiro128+`, if all bits of `a0` and `a1` are zero, + ## they are always zero after calling `next(r: var Rand)`. + not (r.a0 == 0 and r.a1 == 0) since (1, 5): template randState*(): untyped = @@ -617,15 +626,28 @@ proc shuffle*[T](x: var openArray[T]) = shuffle(state, x) -when not defined(nimscript) and not defined(standalone): - import times +when not defined(standalone): + when defined(js): + import std/times + else: + when defined(nimscript): + import std/hashes + else: + import std/[hashes, os, sysrand, monotimes] + + when compileOption("threads"): + import locks + var baseSeedLock: Lock + baseSeedLock.initLock + + var baseState: Rand proc initRand(): Rand = - ## Initializes a new Rand state with a seed based on the current time. + ## Initializes a new Rand state. ## ## The resulting state is independent of the default RNG's state. ## - ## **Note:** Does not work for NimScript or the compile-time VM. + ## **Note:** Does not work for the compile-time VM. ## ## See also: ## * `initRand proc<#initRand,int64>`_ that accepts a seed for a new Rand state @@ -635,20 +657,50 @@ when not defined(nimscript) and not defined(standalone): let time = int64(times.epochTime() * 1000) and 0x7fff_ffff result = initRand(time) else: - let now = times.getTime() - result = initRand(convert(Seconds, Nanoseconds, now.toUnix) + now.nanosecond) + proc getRandomState(): Rand = + when defined(nimscript): + result = Rand( + a0: CompileTime.hash.Ui, + a1: CompileDate.hash.Ui) + if not result.isValid: + result = DefaultRandSeed + else: + var urand: array[sizeof(Rand), byte] + + for i in 0 .. 7: + if sysrand.urandom(urand): + copyMem(result.addr, urand[0].addr, sizeof(Rand)) + if result.isValid: + break + + if not result.isValid: + # Don't try to get alternative random values from other source like time or process/thread id, + # because such code would be never tested and is a liability for security. + quit("Failed to initializes baseState in random module as sysrand.urandom doesn't work.") + + when compileOption("threads"): + baseSeedLock.withLock: + if not baseState.isValid: + baseState = getRandomState() + result = baseState + baseState.skipRandomNumbers + else: + if not baseState.isValid: + baseState = getRandomState() + result = baseState + baseState.skipRandomNumbers since (1, 5, 1): export initRand proc randomize*() {.benign.} = ## Initializes the default random number generator with a seed based on - ## the current time. + ## random number source. ## ## This proc only needs to be called once, and it should be called before ## the first usage of procs from this module that use the default RNG. ## - ## **Note:** Does not work for NimScript or the compile-time VM. + ## **Note:** Does not work for the compile-time VM. ## ## **See also:** ## * `randomize proc<#randomize,int64>`_ that accepts a seed diff --git a/lib/std/tempfiles.nim b/lib/std/tempfiles.nim index f1cfd5885..26786d463 100644 --- a/lib/std/tempfiles.nim +++ b/lib/std/tempfiles.nim @@ -17,7 +17,7 @@ See also: * `mkstemp` (posix), refs https://man7.org/linux/man-pages/man3/mkstemp.3.html ]# -import os, random, std/monotimes +import os, random const @@ -107,11 +107,8 @@ var nimTempPathState {.threadvar.}: NimTempPathState template randomPathName(length: Natural): string = var res = newString(length) if not nimTempPathState.isInit: - var time = getMonoTime().ticks - when compileOption("threads"): - time = time xor int64(getThreadId()) nimTempPathState.isInit = true - nimTempPathState.state = initRand(time) + nimTempPathState.state = initRand() for i in 0 ..< length: res[i] = nimTempPathState.state.sample(letters) diff --git a/tests/stdlib/trandom.nim b/tests/stdlib/trandom.nim index 39ccca85b..61e858f86 100644 --- a/tests/stdlib/trandom.nim +++ b/tests/stdlib/trandom.nim @@ -23,9 +23,10 @@ proc main() = doAssert a in [[0,1], [1,0]] doAssert rand(0) == 0 - doAssert sample("a") == 'a' + when not defined(nimscript): + doAssert sample("a") == 'a' - when compileOption("rangeChecks"): + when compileOption("rangeChecks") and not defined(nimscript): doAssertRaises(RangeDefect): discard rand(-1) @@ -92,7 +93,7 @@ block: # random int block: # again gives new numbers var rand1 = rand(1000000) - when not defined(js): + when not (defined(js) or defined(nimscript)): os.sleep(200) var rand2 = rand(1000000) @@ -122,7 +123,7 @@ block: # random float block: # again gives new numbers var rand1: float = rand(1000000.0) - when not defined(js): + when not (defined(js) or defined(nimscript)): os.sleep(200) var rand2: float = rand(1000000.0) @@ -248,3 +249,26 @@ block: # bug #17670 type UInt48 = range[0'u64..2'u64^48-1] let x = rand(UInt48) doAssert x is UInt48 + +block: # bug #17898 + # Checks whether `initRand()` generates unique states. + # size should be 2^64, but we don't have time and space. + + # Disable this test for js until js gets proper skipRandomNumbers. + when not defined(js): + const size = 1000 + var + rands: array[size, Rand] + randSet: HashSet[Rand] + for i in 0..<size: + rands[i] = initRand() + randSet.incl rands[i] + + doAssert randSet.len == size + + # Checks random number sequences overlapping. + const numRepeat = 100 + for i in 0..<size: + for j in 0..<numRepeat: + discard rands[i].next + doAssert rands[i] notin randSet diff --git a/tests/test_nimscript.nims b/tests/test_nimscript.nims index 2468699a4..90b6181aa 100644 --- a/tests/test_nimscript.nims +++ b/tests/test_nimscript.nims @@ -71,6 +71,8 @@ import std/[ decls, compilesettings, with, wrapnils ] +import stdlib/trandom + echo "Nimscript imports are successful." block: |