Reorganize

safe_libc/Cargo.lock

@@ -0,0 +1,14 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
+name = "libc"
+version = "0.2.68"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dea0c0405123bba743ee3f91f49b1c7cfb684eef0da0a50110f758ccf24cdff0"
+
+[[package]]
+name = "safe_libc"
+version = "0.1.0"
+dependencies = [
+ "libc",
+]

safe_libc/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "safe_libc"
+version = "0.1.0"
+authors = ["Matthias Schiffer <mschiffer@universe-factory.net>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+libc = { version = "0.2.68", default-features = false }

safe_libc/src/boxed.rs

@@ -0,0 +1,146 @@
+use crate::util;
+
+use core::{mem, ptr};
+use core::ops::{Deref, DerefMut};
+
+fn alloc<T>(len: usize) -> *mut T {
+	if util::zst::<T>(len) {
+		return ptr::null_mut();
+	}
+	let size = len.checked_mul(mem::size_of::<T>()).expect("allocation overflow");
+	let align = mem::align_of::<T>();
+	util::must_succeed(
+		unsafe {
+			libc::memalign(align as libc::size_t, size as libc::size_t) as *mut T
+		}
+	)
+}
+
+#[inline]
+fn dangling<T>() -> *mut T {
+	mem::align_of::<T>() as *mut T
+}
+
+#[inline]
+fn slice_len<T>(p: *const [T]) -> usize {
+	unsafe { mem::transmute::<*const [T], [usize; 2]>(p)[1] }
+}
+
+pub struct CBox<T: ?Sized>(*mut T);
+
+impl<T: ?Sized> CBox<T> {
+	#[inline]
+	pub unsafe fn from_raw_unchecked(p: *mut T) -> CBox<T> {
+		CBox(p)
+	}
+
+	#[inline]
+	pub fn into_raw(self) -> *mut T {
+		let p = self.0;
+		mem::forget(self);
+		p
+	}
+
+	#[inline]
+	pub fn as_ptr(&self) -> *const T {
+		self.0
+	}
+
+	#[inline]
+	pub fn as_mut_ptr(&mut self) -> *mut T {
+		self.0
+	}
+}
+
+impl<T> CBox<T> {
+	#[inline]
+	pub fn new(value: T) -> CBox<T> {
+		let p = alloc(1);
+		unsafe {
+			ptr::write(p, value);
+			CBox::from_raw_unchecked(p)
+		}
+	}
+
+	#[inline]
+	pub unsafe fn from_raw(p: *mut T) -> CBox<T> {
+		util::check_ptr(p, 1);
+		CBox(p)
+	}
+
+	#[inline]
+	pub unsafe fn slice_from_raw_parts_unchecked(p: *mut T, len: usize) -> CBox<[T]> {
+		CBox(ptr::slice_from_raw_parts_mut(p, len))
+	}
+
+	#[inline]
+	pub unsafe fn slice_from_raw_parts(p: *mut T, len: usize) -> CBox<[T]> {
+		util::check_ptr(p, len);
+		CBox::slice_from_raw_parts_unchecked(p, len)
+	}
+
+	#[inline]
+	fn safe_ptr(&self) -> *mut T {
+		if util::zst::<T>(1) {
+			return dangling();
+		}
+
+		debug_assert!(!self.0.is_null(), "NULL ptr");
+		self.0
+	}
+}
+
+impl<T> CBox<[T]> {
+	#[inline]
+	fn safe_ptr(&self) -> *mut [T] {
+		if self.0.is_null() {
+			let len = slice_len(self.0);
+			debug_assert!(util::zst::<T>(len), "NULL ptr");
+			return ptr::slice_from_raw_parts_mut(dangling(), len);
+		}
+
+		self.0
+	}
+}
+
+impl<T: ?Sized> Drop for CBox<T> {
+	#[inline]
+	fn drop(&mut self) {
+		unsafe {
+			ptr::drop_in_place(self.0);
+			libc::free(self.0 as *mut libc::c_void);
+		}
+	}
+}
+
+impl<T> Deref for CBox<T> {
+	type Target = T;
+
+	#[inline]
+	fn deref(&self) -> &T {
+		unsafe { &*self.safe_ptr() }
+	}
+}
+
+impl<T> DerefMut for CBox<T> {
+	#[inline]
+	fn deref_mut(&mut self) -> &mut T {
+		unsafe { &mut *self.safe_ptr() }
+	}
+}
+
+impl<T> Deref for CBox<[T]> {
+	type Target = [T];
+
+	#[inline]
+	fn deref(&self) -> &[T] {
+		unsafe { &*self.safe_ptr() }
+	}
+}
+
+impl<T> DerefMut for CBox<[T]> {
+	#[inline]
+	fn deref_mut(&mut self) -> &mut [T] {
+		unsafe { &mut *self.safe_ptr() }
+	}
+}

safe_libc/src/lib.rs

@@ -0,0 +1,18 @@
+#![no_std]
+
+pub use libc::*;
+
+mod util;
+
+pub mod boxed;
+pub mod stdio;
+pub mod string;
+
+
+extern "C" {
+	pub fn strndup(cs: *const libc::c_char, n: libc::size_t) -> *mut libc::c_char;
+
+	// pub static stdin: *mut libc::FILE;
+	pub static stdout: *mut libc::FILE;
+	pub static stderr: *mut libc::FILE;
+}

safe_libc/src/stdio.rs

@@ -0,0 +1,47 @@
+use crate as libc;
+use crate::string;
+
+use core::fmt;
+
+pub struct OStream {
+	file: *mut libc::FILE
+}
+
+#[inline]
+pub unsafe fn stdout() -> OStream {
+	OStream { file: libc::stdout }
+}
+
+#[inline]
+pub unsafe fn stderr() -> OStream {
+	OStream { file: libc::stderr }
+}
+
+impl OStream {
+	#[inline]
+	pub fn write(&mut self, b: &[u8]) {
+		unsafe {
+			libc::fwrite(
+				b.as_ptr() as *const libc::c_void,
+				1,
+				b.len(),
+				self.file,
+			);
+		}
+	}
+
+	#[inline]
+	pub fn puts(&mut self, s: &string::CStr) {
+		unsafe {
+			libc::fputs(s.as_ptr(), self.file);
+		}
+	}
+}
+
+impl fmt::Write for OStream {
+	#[inline]
+	fn write_str(&mut self, s: &str) -> fmt::Result {
+		self.write(s.as_bytes());
+		Ok(())
+	}
+}

safe_libc/src/string.rs

@@ -0,0 +1,151 @@
+use crate as libc;
+use crate::util;
+use crate::boxed::CBox;
+
+use core::slice;
+use core::ops::{Deref, DerefMut};
+
+//pub struct FromBytesWithNulError {}
+
+pub struct CStr { inner: libc::c_char }
+
+impl CStr {
+	#[inline]
+	pub unsafe fn from_ptr_unchecked<'a>(p: *const libc::c_char) -> &'a CStr {
+		&*(p as *const CStr)
+	}
+
+	#[inline]
+	pub unsafe fn from_ptr<'a>(p: *const libc::c_char) -> &'a CStr {
+		util::check_ptr(p, 1);
+		CStr::from_ptr_unchecked(p)
+	}
+
+	#[inline]
+	pub unsafe fn from_mut_ptr_unchecked<'a>(p: *mut libc::c_char) -> &'a mut CStr {
+		&mut *(p as *mut CStr)
+	}
+
+	#[inline]
+	pub unsafe fn from_mut_ptr<'a>(p: *mut libc::c_char) -> &'a mut CStr {
+		util::check_ptr(p, 1);
+		CStr::from_mut_ptr_unchecked(p)
+	}
+
+	#[inline]
+	pub unsafe fn from_bytes_with_nul_unchecked(bytes: &[u8]) -> &CStr {
+		CStr::from_ptr_unchecked(bytes.as_ptr() as *const libc::c_char)
+	}
+
+	// TODO
+	//pub fn from_bytes_with_nul(bytes: &[u8]) -> Result<&CStr, FromBytesWithNulError> {
+	//}
+
+	#[inline]
+	pub fn len(&self) -> usize {
+		unsafe { libc::strlen(self.as_ptr()) as usize }
+	}
+
+	#[inline]
+	pub const fn as_ptr(&self) -> *const libc::c_char {
+		&self.inner
+	}
+
+	#[inline]
+	pub fn as_mut_ptr(&mut self) -> *mut libc::c_char {
+		&mut self.inner
+	}
+
+	#[inline]
+	pub fn as_bytes(&self) -> &[u8] {
+		unsafe { slice::from_raw_parts(
+			self.as_ptr() as *const u8,
+			self.len(),
+		) }
+	}
+
+	#[inline]
+	pub fn as_mut_bytes(&mut self) -> &mut [u8] {
+		unsafe { slice::from_raw_parts_mut(
+			self.as_mut_ptr() as *mut u8,
+			self.len(),
+		) }
+	}
+
+	#[inline]
+	pub fn to_owned(self: &CStr) -> CString {
+		CString::from(self)
+	}
+}
+
+#[macro_export]
+macro_rules! cstr {
+	($s:expr) => (
+		unsafe { $crate::string::CStr::from_bytes_with_nul_unchecked(concat!($s, "\0").as_bytes()) }
+	)
+}
+
+pub struct CString { inner: CBox<libc::c_char> }
+
+impl CString {
+	#[inline]
+	pub unsafe fn from_raw_unchecked(p: *mut libc::c_char) -> CString {
+		CString { inner: CBox::from_raw_unchecked(p) }
+	}
+
+	#[inline]
+	pub unsafe fn from_raw(p: *mut libc::c_char) -> CString {
+		util::check_ptr(p, 1);
+		CString::from_raw_unchecked(p)
+	}
+
+	#[inline]
+	pub fn into_raw(self) -> *mut libc::c_char {
+		self.inner.into_raw()
+	}
+}
+
+impl Deref for CString {
+	type Target = CStr;
+
+	#[inline]
+	fn deref(&self) -> &CStr {
+		unsafe { CStr::from_ptr(&*self.inner) }
+	}
+}
+
+impl DerefMut for CString {
+	#[inline]
+	fn deref_mut(&mut self) -> &mut CStr {
+		unsafe { CStr::from_mut_ptr(&mut *self.inner) }
+	}
+}
+
+impl From<&[u8]> for CString {
+	fn from(s: &[u8]) -> CString {
+		unsafe {
+			CString::from_raw_unchecked(
+				util::must_succeed(libc::strndup(
+					s.as_ptr() as *const libc::c_char,
+					s.len() as libc::size_t,
+				))
+			)
+		}
+	}
+}
+
+impl From<&str> for CString {
+	#[inline]
+	fn from(s: &str) -> CString {
+		CString::from(s.as_bytes())
+	}
+}
+
+impl From<&CStr> for CString {
+	#[inline]
+	fn from(s: &CStr) -> CString {
+		unsafe {
+			CString::from_raw_unchecked(util::must_succeed(libc::strdup(s.as_ptr())))
+		}
+	}
+}

safe_libc/src/util.rs

@@ -0,0 +1,18 @@
+use core::mem;
+
+#[inline]
+pub fn zst<T>(len: usize) -> bool {
+	mem::size_of::<T>() == 0 || len == 0
+}
+
+#[inline]
+pub fn check_ptr<T>(p: *const T, len: usize) {
+	debug_assert!((p as usize) % mem::align_of::<T>() == 0, "unaligned ptr");
+	assert!(zst::<T>(len) || !p.is_null(), "NULL ptr");
+}
+
+#[inline]
+pub fn must_succeed<T>(p: *mut T) -> *mut T {
+	assert!(!p.is_null(), "allocation failure");
+	p
+}