nwaku/library/alloc.nim

38 lines
1.2 KiB
Nim

## Can be shared safely between threads
type SharedSeq*[T] = tuple[data: ptr UncheckedArray[T], len: int]
proc alloc*(str: cstring): cstring =
# Byte allocation from the given address.
# There should be the corresponding manual deallocation with deallocShared !
let ret = cast[cstring](allocShared(len(str) + 1))
copyMem(ret, str, len(str) + 1)
return ret
proc alloc*(str: string): cstring =
## Byte allocation from the given address.
## There should be the corresponding manual deallocation with deallocShared !
var ret = cast[cstring](allocShared(str.len + 1))
let s = cast[seq[char]](str)
for i in 0..<str.len:
ret[i] = s[i]
ret[str.len] = '\0'
return ret
proc allocSharedSeq*[T](s: seq[T]): SharedSeq[T] =
let data = allocShared(sizeof(T) * s.len)
if s.len != 0:
copyMem(data, unsafeAddr s[0], s.len)
return (cast[ptr UncheckedArray[T]](data), s.len)
proc deallocSharedSeq*[T](s: var SharedSeq[T]) =
deallocShared(s.data)
s.len = 0
proc toSeq*[T](s: SharedSeq[T]): seq[T] =
## Creates a seq[T] from a SharedSeq[T]. No explicit dealloc is required
## as req[T] is a GC managed type.
var ret = newSeq[T]()
for i in 0..<s.len:
ret.add(s.data[i])
return ret