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dynlib: use posix module (#11623)

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This commit is contained in:
Jacek Sieka 2019-07-08 09:14:35 +02:00 • committed by Miran
commit 9e7d885f35
6 changed files with 32 additions and 50 deletions
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33
tests/mmaptest.nim
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@ -1,25 +1,7 @@
# Small test program to test for mmap() weirdnesses
include "lib/system/ansi_c"
const
PageSize = 4096
PROT_READ = 1 # page can be read
PROT_WRITE = 2 # page can be written
MAP_PRIVATE = 2 # Changes are private
when defined(macosx) or defined(bsd):
const MAP_ANONYMOUS = 0x1000
elif defined(solaris):
const MAP_ANONYMOUS = 0x100
else:
var
MAP_ANONYMOUS {.importc: "MAP_ANONYMOUS", header: "<sys/mman.h>".}: cint
proc mmap(adr: pointer, len: int, prot, flags, fildes: cint,
off: int): pointer {.header: "<sys/mman.h>".}
proc munmap(adr: pointer, len: int) {.header: "<sys/mman.h>".}
import system/ansi_c
import posix
proc osAllocPages(size: int): pointer {.inline.} =
result = mmap(nil, size, PROT_READ or PROT_WRITE,
@ -31,18 +13,21 @@ proc osAllocPages(size: int): pointer {.inline.} =
proc osDeallocPages(p: pointer, size: int) {.inline} =
cfprintf(c_stdout, "freed pages %p..%p\n", p, cast[int](p) + size)
munmap(p, size-1)
discard munmap(p, size-1)
proc `+!!`(p: pointer, size: int): pointer {.inline.} =
result = cast[pointer](cast[int](p) + size)
const
PageShift = when defined(cpu16): 8 else: 12 # \
# my tests showed no improvments for using larger page sizes.
PageSize = 1 shl PageShift
var p = osAllocPages(3 * PageSize)
osDeallocPages(p, PageSize)
# If this fails the OS has freed the whole block starting at 'p':
echo(cast[ptr int](p +!! (pageSize*2))[])
echo(cast[ptr int](p +!! (PageSize*2))[])
osDeallocPages(p +!! PageSize*2, PageSize)
osDeallocPages(p +!! PageSize, PageSize)