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//! Libc call arguments and return values are often things like `c_int`,
//! `c_uint`, or libc-specific pointer types. This module provides functions
//! for converting between rustix's types and libc types.
use super::c;
#[cfg(all(feature = "alloc", not(any(windows, target_os = "espidf"))))]
use super::fd::IntoRawFd;
use super::fd::{AsRawFd, BorrowedFd, FromRawFd, LibcFd, OwnedFd, RawFd};
#[cfg(not(windows))]
use crate::ffi::CStr;
use crate::io;
#[cfg(not(windows))]
#[inline]
pub(super) fn c_str(c: &CStr) -> *const c::c_char {
c.as_ptr()
}
#[cfg(not(any(windows, target_os = "espidf", target_os = "vita", target_os = "wasi")))]
#[inline]
pub(super) fn no_fd() -> LibcFd {
-1
}
#[inline]
pub(super) fn borrowed_fd(fd: BorrowedFd<'_>) -> LibcFd {
fd.as_raw_fd() as LibcFd
}
#[cfg(all(
feature = "alloc",
not(any(windows, target_os = "espidf", target_os = "redox"))
))]
#[inline]
pub(super) fn owned_fd(fd: OwnedFd) -> LibcFd {
fd.into_raw_fd() as LibcFd
}
#[inline]
pub(super) fn ret(raw: c::c_int) -> io::Result<()> {
if raw == 0 {
Ok(())
} else {
Err(io::Errno::last_os_error())
}
}
#[cfg(apple)]
#[inline]
pub(super) fn nonnegative_ret(raw: c::c_int) -> io::Result<()> {
if raw >= 0 {
Ok(())
} else {
Err(io::Errno::last_os_error())
}
}
#[cfg(not(any(windows, target_os = "wasi")))]
#[inline]
pub(super) unsafe fn ret_infallible(raw: c::c_int) {
debug_assert_eq!(raw, 0, "unexpected error: {:?}", io::Errno::last_os_error());
}
#[inline]
pub(super) fn ret_c_int(raw: c::c_int) -> io::Result<c::c_int> {
if raw == -1 {
Err(io::Errno::last_os_error())
} else {
Ok(raw)
}
}
#[cfg(any(linux_kernel, all(target_os = "redox", feature = "event")))]
#[inline]
pub(super) fn ret_u32(raw: c::c_int) -> io::Result<u32> {
if raw == -1 {
Err(io::Errno::last_os_error())
} else {
Ok(raw as u32)
}
}
#[inline]
pub(super) fn ret_usize(raw: c::ssize_t) -> io::Result<usize> {
if raw == -1 {
Err(io::Errno::last_os_error())
} else {
debug_assert!(raw >= 0);
Ok(raw as usize)
}
}
#[cfg(not(windows))]
#[cfg(feature = "fs")]
#[inline]
pub(super) fn ret_off_t(raw: c::off_t) -> io::Result<c::off_t> {
if raw == -1 {
Err(io::Errno::last_os_error())
} else {
Ok(raw)
}
}
#[cfg(not(any(windows, target_os = "wasi")))]
#[inline]
pub(super) fn ret_pid_t(raw: c::pid_t) -> io::Result<c::pid_t> {
if raw == -1 {
Err(io::Errno::last_os_error())
} else {
Ok(raw)
}
}
/// Convert a `c_int` returned from a libc function to an `OwnedFd`, if valid.
///
/// # Safety
///
/// The caller must ensure that this is the return value of a libc function
/// which returns an owned file descriptor.
#[inline]
pub(super) unsafe fn ret_owned_fd(raw: LibcFd) -> io::Result<OwnedFd> {
if raw == !0 {
Err(io::Errno::last_os_error())
} else {
Ok(OwnedFd::from_raw_fd(raw as RawFd))
}
}
#[cfg(not(any(windows, target_os = "wasi")))]
#[inline]
pub(super) fn ret_discarded_fd(raw: LibcFd) -> io::Result<()> {
if raw == !0 {
Err(io::Errno::last_os_error())
} else {
Ok(())
}
}
#[cfg(all(feature = "alloc", not(any(windows, target_os = "wasi"))))]
#[inline]
pub(super) fn ret_discarded_char_ptr(raw: *mut c::c_char) -> io::Result<()> {
if raw.is_null() {
Err(io::Errno::last_os_error())
} else {
Ok(())
}
}
/// Convert the buffer-length argument value of a `send` or `recv` call.
#[cfg(not(any(windows, target_os = "redox", target_os = "wasi")))]
#[inline]
pub(super) fn send_recv_len(len: usize) -> usize {
len
}
/// Convert the buffer-length argument value of a `send` or `recv` call.
#[cfg(windows)]
#[inline]
pub(super) fn send_recv_len(len: usize) -> i32 {
// On Windows, the length argument has type `i32`; saturate the length,
// since `send` and `recv` are allowed to send and recv less data than
// requested.
len.try_into().unwrap_or(i32::MAX)
}
/// Convert the return value of a `send` or `recv` call.
#[cfg(not(any(windows, target_os = "redox", target_os = "wasi")))]
#[inline]
pub(super) fn ret_send_recv(len: isize) -> io::Result<usize> {
ret_usize(len)
}
/// Convert the return value of a `send` or `recv` call.
#[cfg(windows)]
#[inline]
pub(super) fn ret_send_recv(len: i32) -> io::Result<usize> {
ret_usize(len as isize)
}
/// Convert the value to the `msg_iovlen` field of a `msghdr` struct.
#[cfg(all(
not(any(windows, target_os = "espidf", target_os = "redox", target_os = "wasi")),
any(
target_os = "android",
all(
target_os = "linux",
not(target_env = "musl"),
not(all(target_env = "uclibc", any(target_arch = "arm", target_arch = "mips")))
)
)
))]
#[inline]
pub(super) fn msg_iov_len(len: usize) -> c::size_t {
len
}
/// Convert the value to the `msg_iovlen` field of a `msghdr` struct.
#[cfg(all(
not(any(
windows,
target_os = "espidf",
target_os = "redox",
target_os = "vita",
target_os = "wasi"
)),
not(any(
target_os = "android",
all(
target_os = "linux",
not(target_env = "musl"),
not(all(target_env = "uclibc", any(target_arch = "arm", target_arch = "mips")))
)
))
))]
#[inline]
pub(crate) fn msg_iov_len(len: usize) -> c::c_int {
len.try_into().unwrap_or(c::c_int::MAX)
}
/// Convert the value to a `socklen_t`.
#[cfg(any(
bsd,
solarish,
target_env = "musl",
target_os = "aix",
target_os = "emscripten",
target_os = "fuchsia",
target_os = "haiku",
target_os = "nto",
))]
#[inline]
pub(crate) fn msg_control_len(len: usize) -> c::socklen_t {
len.try_into().unwrap_or(c::socklen_t::MAX)
}
/// Convert the value to a `size_t`.
#[cfg(not(any(
bsd,
solarish,
windows,
target_env = "musl",
target_os = "aix",
target_os = "emscripten",
target_os = "espidf",
target_os = "fuchsia",
target_os = "haiku",
target_os = "nto",
target_os = "redox",
target_os = "vita",
target_os = "wasi",
)))]
#[inline]
pub(crate) fn msg_control_len(len: usize) -> c::size_t {
len
}