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# This file is a part of Julia. License is MIT: https://julialang.org/license
module Libc
import Base: transcode
export FILE, TmStruct, strftime, strptime, getpid, gethostname, free, malloc, calloc, realloc,
errno, strerror, flush_cstdio, systemsleep, time, transcode
if is_windows()
export GetLastError, FormatMessage
end
include(string(length(Core.ARGS)>=2?Core.ARGS[2]:"","errno_h.jl")) # include($BUILDROOT/base/errno_h.jl)
## RawFD ##
# Wrapper for an OS file descriptor (on both Unix and Windows)
struct RawFD
fd::Int32
RawFD(fd::Integer) = new(fd)
RawFD(fd::RawFD) = fd
end
Base.cconvert(::Type{Int32}, fd::RawFD) = fd.fd
dup(x::RawFD) = RawFD(ccall((@static is_windows() ? :_dup : :dup), Int32, (Int32,), x.fd))
dup(src::RawFD, target::RawFD) = systemerror("dup", -1 ==
ccall((@static is_windows() ? :_dup2 : :dup2), Int32,
(Int32, Int32), src.fd, target.fd))
# Wrapper for an OS file descriptor (for Windows)
if is_windows()
struct WindowsRawSocket
handle::Ptr{Void} # On Windows file descriptors are HANDLE's and 64-bit on 64-bit Windows
end
Base.cconvert(::Type{Ptr{Void}}, fd::WindowsRawSocket) = fd.handle
_get_osfhandle(fd::RawFD) = WindowsRawSocket(ccall(:_get_osfhandle, Ptr{Void}, (Cint,), fd.fd))
_get_osfhandle(fd::WindowsRawSocket) = fd
function dup(src::WindowsRawSocket)
new_handle = Ref{Ptr{Void}}(-1)
my_process = ccall(:GetCurrentProcess, stdcall, Ptr{Void}, ())
const DUPLICATE_SAME_ACCESS = 0x2
status = ccall(:DuplicateHandle, stdcall, Int32,
(Ptr{Void}, Ptr{Void}, Ptr{Void}, Ptr{Ptr{Void}}, UInt32, Int32, UInt32),
my_process, src.handle, my_process, new_handle, 0, false, DUPLICATE_SAME_ACCESS)
status == 0 && error("dup failed: $(FormatMessage())")
return new_handle[]
end
function dup(src::WindowsRawSocket, target::RawFD)
fd = ccall(:_open_osfhandle, Int32, (Ptr{Void}, Int32), dup(src), 0)
dup(RawFD(fd), target)
ccall(:_close, Int32, (Int32,), fd)
nothing
end
else
_get_osfhandle(fd::RawFD) = fd
end
## FILE (not auto-finalized) ##
struct FILE
ptr::Ptr{Void}
end
modestr(s::IO) = modestr(isreadable(s), iswritable(s))
modestr(r::Bool, w::Bool) = r ? (w ? "r+" : "r") : (w ? "w" : throw(ArgumentError("neither readable nor writable")))
function FILE(fd::RawFD, mode)
FILEp = ccall((@static is_windows() ? :_fdopen : :fdopen), Ptr{Void}, (Cint, Cstring), fd, mode)
systemerror("fdopen", FILEp == C_NULL)
FILE(FILEp)
end
function FILE(s::IO)
f = FILE(dup(RawFD(fd(s))),modestr(s))
seek(f, position(s))
f
end
Base.unsafe_convert(T::Union{Type{Ptr{Void}},Type{Ptr{FILE}}}, f::FILE) = convert(T, f.ptr)
Base.close(f::FILE) = systemerror("fclose", ccall(:fclose, Cint, (Ptr{Void},), f.ptr) != 0)
Base.convert(::Type{FILE}, s::IO) = FILE(s)
function Base.seek(h::FILE, offset::Integer)
systemerror("fseek", ccall(:fseek, Cint, (Ptr{Void}, Clong, Cint),
h.ptr, offset, 0) != 0)
h
end
Base.position(h::FILE) = ccall(:ftell, Clong, (Ptr{Void},), h.ptr)
# flush C stdio output from external libraries
"""
flush_cstdio()
Flushes the C `stdout` and `stderr` streams (which may have been written to by external C code).
"""
flush_cstdio() = ccall(:jl_flush_cstdio, Void, ())
## time-related functions ##
# TODO: check for usleep errors?
if is_unix()
systemsleep(s::Real) = ccall(:usleep, Int32, (UInt32,), round(UInt32, s*1e6))
elseif is_windows()
function systemsleep(s::Real)
ccall(:Sleep, stdcall, Void, (UInt32,), round(UInt32, s * 1e3))
return Int32(0)
end
else
error("systemsleep undefined for this OS")
end
struct TimeVal
sec::Int64
usec::Int64
end
function TimeVal()
tv = Ref{TimeVal}()
status = ccall(:jl_gettimeofday, Cint, (Ref{TimeVal},), tv)
status != 0 && error("unable to determine current time: ", status)
return tv[]
end
"""
TmStruct([seconds])
Convert a number of seconds since the epoch to broken-down format, with fields `sec`, `min`,
`hour`, `mday`, `month`, `year`, `wday`, `yday`, and `isdst`.
"""
mutable struct TmStruct
sec::Int32
min::Int32
hour::Int32
mday::Int32
month::Int32
year::Int32
wday::Int32
yday::Int32
isdst::Int32
# on some platforms the struct is 14 words, even though 9 are specified
_10::Int32
_11::Int32
_12::Int32
_13::Int32
_14::Int32
TmStruct(sec, min, hour, mday, month, year, wday, yday, isdst) =
new(sec, min, hour, mday, month, year, wday, yday, isdst, 0,0,0,0,0)
TmStruct() = new(0,0,0,0,0,0,0,0,0,0,0,0,0,0)
function TmStruct(t::Real)
t = floor(t)
tm = TmStruct()
# TODO: add support for UTC via gmtime_r()
ccall(:localtime_r, Ptr{TmStruct}, (Ptr{Int}, Ptr{TmStruct}), &t, &tm)
return tm
end
end
"""
strftime([format], time)
Convert time, given as a number of seconds since the epoch or a `TmStruct`, to a formatted
string using the given format. Supported formats are the same as those in the standard C
library.
"""
strftime(t) = strftime("%c", t)
strftime(fmt::AbstractString, t::Real) = strftime(fmt, TmStruct(t))
function strftime(fmt::AbstractString, tm::TmStruct)
timestr = Vector{UInt8}(128)
n = ccall(:strftime, Int, (Ptr{UInt8}, Int, Cstring, Ptr{TmStruct}),
timestr, length(timestr), fmt, &tm)
if n == 0
return ""
end
return String(timestr[1:n])
end
"""
strptime([format], timestr)
Parse a formatted time string into a `TmStruct` giving the seconds, minute, hour, date, etc.
Supported formats are the same as those in the standard C library. On some platforms,
timezones will not be parsed correctly. If the result of this function will be passed to
`time` to convert it to seconds since the epoch, the `isdst` field should be filled in
manually. Setting it to `-1` will tell the C library to use the current system settings to
determine the timezone.
"""
strptime(timestr::AbstractString) = strptime("%c", timestr)
function strptime(fmt::AbstractString, timestr::AbstractString)
tm = TmStruct()
r = ccall(:strptime, Cstring, (Cstring, Cstring, Ptr{TmStruct}),
timestr, fmt, &tm)
# the following would tell mktime() that this is a local time, and that
# it should try to guess the timezone. not sure if/how this should be
# exposed in the API.
# tm.isdst = -1
if r == C_NULL
# TODO: better error message
throw(ArgumentError("invalid arguments"))
end
@static if is_apple()
# if we didn't explicitly parse the weekday or year day, use mktime
# to fill them in automatically.
if !ismatch(r"([^%]|^)%(a|A|j|w|Ow)", fmt)
ccall(:mktime, Int, (Ptr{TmStruct},), &tm)
end
end
return tm
end
# system date in seconds
"""
time(t::TmStruct)
Converts a `TmStruct` struct to a number of seconds since the epoch.
"""
time(tm::TmStruct) = Float64(ccall(:mktime, Int, (Ptr{TmStruct},), &tm))
time() = ccall(:jl_clock_now, Float64, ())
## process-related functions ##
"""
getpid() -> Int32
Get Julia's process ID.
"""
getpid() = ccall(:jl_getpid, Int32, ())
## network functions ##
"""
gethostname() -> AbstractString
Get the local machine's host name.
"""
function gethostname()
hn = Vector{UInt8}(256)
err = @static if is_windows()
ccall(:gethostname, stdcall, Int32, (Ptr{UInt8}, UInt32), hn, length(hn))
else
ccall(:gethostname, Int32, (Ptr{UInt8}, UInt), hn, length(hn))
end
systemerror("gethostname", err != 0)
return unsafe_string(pointer(hn))
end
## system error handling ##
"""
errno([code])
Get the value of the C library's `errno`. If an argument is specified, it is used to set the
value of `errno`.
The value of `errno` is only valid immediately after a `ccall` to a C library routine that
sets it. Specifically, you cannot call `errno` at the next prompt in a REPL, because lots of
code is executed between prompts.
"""
errno() = ccall(:jl_errno, Cint, ())
errno(e::Integer) = ccall(:jl_set_errno, Void, (Cint,), e)
"""
strerror(n=errno())
Convert a system call error code to a descriptive string
"""
strerror(e::Integer) = unsafe_string(ccall(:strerror, Cstring, (Int32,), e))
strerror() = strerror(errno())
"""
GetLastError()
Call the Win32 `GetLastError` function [only available on Windows].
"""
function GetLastError end
"""
FormatMessage(n=GetLastError())
Convert a Win32 system call error code to a descriptive string [only available on Windows].
"""
function FormatMessage end
if is_windows()
GetLastError() = ccall(:GetLastError, stdcall, UInt32, ())
function FormatMessage(e=GetLastError())
const FORMAT_MESSAGE_ALLOCATE_BUFFER = UInt32(0x100)
const FORMAT_MESSAGE_FROM_SYSTEM = UInt32(0x1000)
const FORMAT_MESSAGE_IGNORE_INSERTS = UInt32(0x200)
const FORMAT_MESSAGE_MAX_WIDTH_MASK = UInt32(0xFF)
lpMsgBuf = Ref{Ptr{UInt16}}()
lpMsgBuf[] = 0
len = ccall(:FormatMessageW, stdcall, UInt32, (Cint, Ptr{Void}, Cint, Cint, Ptr{Ptr{UInt16}}, Cint, Ptr{Void}),
FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_MAX_WIDTH_MASK,
C_NULL, e, 0, lpMsgBuf, 0, C_NULL)
p = lpMsgBuf[]
len == 0 && return ""
buf = Vector{UInt16}(len)
unsafe_copy!(pointer(buf), p, len)
ccall(:LocalFree, stdcall, Ptr{Void}, (Ptr{Void},), p)
return transcode(String, buf)
end
end
## Memory related ##
"""
free(addr::Ptr)
Call `free` from the C standard library. Only use this on memory obtained from `malloc`, not
on pointers retrieved from other C libraries. `Ptr` objects obtained from C libraries should
be freed by the free functions defined in that library, to avoid assertion failures if
multiple `libc` libraries exist on the system.
"""
free(p::Ptr) = ccall(:free, Void, (Ptr{Void},), p)
"""
malloc(size::Integer) -> Ptr{Void}
Call `malloc` from the C standard library.
"""
malloc(size::Integer) = ccall(:malloc, Ptr{Void}, (Csize_t,), size)
"""
realloc(addr::Ptr, size::Integer) -> Ptr{Void}
Call `realloc` from the C standard library.
See warning in the documentation for `free` regarding only using this on memory originally
obtained from `malloc`.
"""
realloc(p::Ptr, size::Integer) = ccall(:realloc, Ptr{Void}, (Ptr{Void}, Csize_t), p, size)
"""
calloc(num::Integer, size::Integer) -> Ptr{Void}
Call `calloc` from the C standard library.
"""
calloc(num::Integer, size::Integer) = ccall(:calloc, Ptr{Void}, (Csize_t, Csize_t), num, size)
free(p::Cstring) = free(convert(Ptr{UInt8}, p))
free(p::Cwstring) = free(convert(Ptr{Cwchar_t}, p))
end # module