| //! 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. |
| |
| #![allow(dead_code)] |
| |
| use super::c; |
| use super::fd::{AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, LibcFd, OwnedFd, RawFd}; |
| #[cfg(not(windows))] |
| #[cfg(feature = "fs")] |
| use super::offset::libc_off_t; |
| #[cfg(not(windows))] |
| use crate::ffi::CStr; |
| use crate::io; |
| #[cfg(windows)] |
| use core::convert::TryInto; |
| |
| #[cfg(not(windows))] |
| #[inline] |
| pub(super) fn c_str(c: &CStr) -> *const c::c_char { |
| c.as_ptr() |
| } |
| |
| #[cfg(not(windows))] |
| #[inline] |
| pub(super) fn no_fd() -> LibcFd { |
| -1 |
| } |
| |
| #[inline] |
| pub(super) fn borrowed_fd(fd: BorrowedFd<'_>) -> LibcFd { |
| fd.as_raw_fd() as LibcFd |
| } |
| |
| #[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()) |
| } |
| } |
| |
| #[inline] |
| pub(super) fn syscall_ret(raw: c::c_long) -> io::Result<()> { |
| if raw == 0 { |
| Ok(()) |
| } else { |
| Err(io::Errno::last_os_error()) |
| } |
| } |
| |
| #[inline] |
| pub(super) fn nonnegative_ret(raw: c::c_int) -> io::Result<()> { |
| if raw >= 0 { |
| Ok(()) |
| } else { |
| Err(io::Errno::last_os_error()) |
| } |
| } |
| |
| #[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) |
| } |
| } |
| |
| #[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_ssize_t(raw: c::ssize_t) -> io::Result<c::ssize_t> { |
| if raw == -1 { |
| Err(io::Errno::last_os_error()) |
| } else { |
| Ok(raw) |
| } |
| } |
| |
| #[inline] |
| pub(super) fn syscall_ret_ssize_t(raw: c::c_long) -> io::Result<c::ssize_t> { |
| if raw == -1 { |
| Err(io::Errno::last_os_error()) |
| } else { |
| Ok(raw as c::ssize_t) |
| } |
| } |
| |
| #[cfg(any(target_os = "android", target_os = "linux"))] |
| #[inline] |
| pub(super) fn syscall_ret_u32(raw: c::c_long) -> io::Result<u32> { |
| if raw == -1 { |
| Err(io::Errno::last_os_error()) |
| } else { |
| let r32 = raw as u32; |
| |
| // Converting `raw` to `u32` should be lossless. |
| debug_assert_eq!(r32 as c::c_long, raw); |
| |
| Ok(r32) |
| } |
| } |
| |
| #[cfg(not(windows))] |
| #[cfg(feature = "fs")] |
| #[inline] |
| pub(super) fn ret_off_t(raw: libc_off_t) -> io::Result<libc_off_t> { |
| if raw == -1 { |
| Err(io::Errno::last_os_error()) |
| } else { |
| Ok(raw) |
| } |
| } |
| |
| #[cfg(not(windows))] |
| #[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)) |
| } |
| } |
| |
| #[inline] |
| pub(super) fn ret_discarded_fd(raw: LibcFd) -> io::Result<()> { |
| if raw == !0 { |
| Err(io::Errno::last_os_error()) |
| } else { |
| Ok(()) |
| } |
| } |
| |
| #[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 a `c_long` returned from `syscall` to an `OwnedFd`, if valid. |
| /// |
| /// # Safety |
| /// |
| /// The caller must ensure that this is the return value of a `syscall` call |
| /// which returns an owned file descriptor. |
| #[cfg(not(windows))] |
| #[inline] |
| pub(super) unsafe fn syscall_ret_owned_fd(raw: c::c_long) -> io::Result<OwnedFd> { |
| if raw == -1 { |
| Err(io::Errno::last_os_error()) |
| } else { |
| Ok(OwnedFd::from_raw_fd(raw as RawFd)) |
| } |
| } |
| |
| /// Convert the buffer-length argument value of a `send` or `recv` call. |
| #[cfg(not(windows))] |
| #[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(windows))] |
| #[inline] |
| pub(super) fn ret_send_recv(len: isize) -> io::Result<c::ssize_t> { |
| ret_ssize_t(len) |
| } |
| |
| /// Convert the return value of a `send` or `recv` call. |
| #[cfg(windows)] |
| #[inline] |
| pub(super) fn ret_send_recv(len: i32) -> io::Result<c::ssize_t> { |
| ret_ssize_t(len as isize) |
| } |