WIP: Cross-compilation for Redox target

Author: jackpot51

src/liballoc_jemalloc/build.rs

@@ -36,7 +36,8 @@ fn main() {
     // targets, which means we have to build the alloc_jemalloc crate
     // for targets like emscripten, even if we don't use it.
     if target.contains("rumprun") || target.contains("bitrig") || target.contains("openbsd") ||
-       target.contains("msvc") || target.contains("emscripten") || target.contains("fuchsia") {
+       target.contains("msvc") || target.contains("emscripten") || target.contains("fuchsia") ||
+       target.contains("redox") {
         println!("cargo:rustc-cfg=dummy_jemalloc");
         return;
     }

src/liballoc_system/lib.rs

@@ -19,6 +19,7 @@
             issue = "27783")]
 #![feature(allocator)]
 #![feature(staged_api)]
+#![cfg_attr(target_os = "redox", feature(libc))]
 #![cfg_attr(unix, feature(libc))]
 
 // The minimum alignment guaranteed by the architecture. This value is used to
@@ -71,7 +72,49 @@ pub extern "C" fn __rust_usable_size(size: usize, align: usize) -> usize {
     imp::usable_size(size, align)
 }
 
-#[cfg(unix)]
+#[cfg(target_os = "redox")]
+mod imp {
+    extern crate libc;
+
+    use core::cmp;
+    use core::ptr;
+    use MIN_ALIGN;
+
+    pub unsafe fn allocate(size: usize, _align: usize) -> *mut u8 {
+        libc::malloc(size as libc::size_t) as *mut u8
+    }
+
+    pub unsafe fn reallocate(ptr: *mut u8, old_size: usize, size: usize, align: usize) -> *mut u8 {
+        if align <= MIN_ALIGN {
+            libc::realloc(ptr as *mut libc::c_void, size as libc::size_t) as *mut u8
+        } else {
+            let new_ptr = allocate(size, align);
+            if !new_ptr.is_null() {
+                ptr::copy(ptr, new_ptr, cmp::min(size, old_size));
+                deallocate(ptr, old_size, align);
+            }
+            new_ptr
+        }
+    }
+
+    pub unsafe fn reallocate_inplace(_ptr: *mut u8,
+                                     old_size: usize,
+                                     _size: usize,
+                                     _align: usize)
+                                     -> usize {
+        old_size
+    }
+
+    pub unsafe fn deallocate(ptr: *mut u8, _old_size: usize, _align: usize) {
+        libc::free(ptr as *mut libc::c_void)
+    }
+
+    pub fn usable_size(size: usize, _align: usize) -> usize {
+        size
+    }
+}
+
+#[cfg(any(unix))]
 mod imp {
     extern crate libc;
 

src/libstd/Cargo.toml

@@ -23,6 +23,9 @@ compiler_builtins = { path = "../libcompiler_builtins" }
 std_unicode = { path = "../libstd_unicode" }
 unwind = { path = "../libunwind" }
 
+[replace]
+"core:0.0.0" = { path = "../libcore" }
+
 [build-dependencies]
 build_helper = { path = "../build_helper" }
 gcc = "0.3.27"

src/libstd/build.rs

@@ -26,7 +26,7 @@ fn main() {
     let target = env::var("TARGET").expect("TARGET was not set");
     let host = env::var("HOST").expect("HOST was not set");
     if cfg!(feature = "backtrace") && !target.contains("apple") && !target.contains("msvc") &&
-        !target.contains("emscripten") && !target.contains("fuchsia") {
+        !target.contains("emscripten") && !target.contains("fuchsia") && !target.contains("redox") {
         build_libbacktrace(&host, &target);
     }
 

src/libstd/lib.rs

@@ -299,6 +299,7 @@
 #![feature(unwind_attributes)]
 #![feature(vec_push_all)]
 #![feature(zero_one)]
+#![cfg_attr(target_os = "redox", feature(naked_functions))]
 #![cfg_attr(test, feature(update_panic_count))]
 
 // Explicitly import the prelude. The compiler uses this same unstable attribute

src/libstd/sys/redox/mod.rs

@@ -10,8 +10,6 @@
 
 #![allow(dead_code, missing_docs, bad_style)]
 
-pub extern crate syscall;
-
 use io::{self, ErrorKind};
 
 pub mod args;
@@ -33,7 +31,9 @@ pub mod process;
 pub mod rand;
 pub mod rwlock;
 pub mod stack_overflow;
+pub mod start;
 pub mod stdio;
+pub mod syscall;
 pub mod thread;
 pub mod thread_local;
 pub mod time;

src/libstd/sys/redox/net/mod.rs

@@ -20,10 +20,11 @@ use vec::{IntoIter, Vec};
 
 use self::dns::{Dns, DnsQuery};
 
-pub extern crate libc as netc;
 pub use self::tcp::{TcpStream, TcpListener};
 pub use self::udp::UdpSocket;
 
+pub mod netc;
+
 mod dns;
 mod tcp;
 mod udp;

src/libstd/sys/redox/net/netc.rs

@@ -0,0 +1,47 @@
+pub type in_addr_t = u32;
+pub type in_port_t = u16;
+
+pub type socklen_t = u32;
+pub type sa_family_t = u16;
+
+pub const AF_INET: sa_family_t = 1;
+pub const AF_INET6: sa_family_t = 2;
+
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub struct in_addr {
+    pub s_addr: in_addr_t,
+}
+
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub struct in6_addr {
+    pub s6_addr: [u8; 16],
+    __align: [u32; 0],
+}
+
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub struct sockaddr {
+    pub sa_family: sa_family_t,
+    pub sa_data: [u8; 14],
+}
+
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub struct sockaddr_in {
+    pub sin_family: sa_family_t,
+    pub sin_port: in_port_t,
+    pub sin_addr: in_addr,
+    pub sin_zero: [u8; 8],
+}
+
+#[derive(Copy, Clone)]
+#[repr(C)]
+pub struct sockaddr_in6 {
+    pub sin6_family: sa_family_t,
+    pub sin6_port: in_port_t,
+    pub sin6_flowinfo: u32,
+    pub sin6_addr: in6_addr,
+    pub sin6_scope_id: u32,
+}

src/libstd/sys/redox/rand.rs

@@ -9,15 +9,19 @@
 // except according to those terms.
 
 use io;
-use libc;
 use rand::Rng;
 
-pub struct OsRng;
+// FIXME: Use rand:
+pub struct OsRng {
+    state: [u64; 2]
+}
 
 impl OsRng {
     /// Create a new `OsRng`.
     pub fn new() -> io::Result<OsRng> {
-        Ok(OsRng)
+        Ok(OsRng {
+            state: [0xBADF00D1, 0xDEADBEEF]
+        })
     }
 }
 
@@ -26,7 +30,20 @@ impl Rng for OsRng {
         self.next_u64() as u32
     }
     fn next_u64(&mut self) -> u64 {
-        unsafe { libc::random() }
+        // Store the first and second part.
+        let mut x = self.state[0];
+        let y = self.state[1];
+
+        // Put the second part into the first slot.
+        self.state[0] = y;
+        // Twist the first slot.
+        x ^= x << 23;
+        // Update the second slot.
+        self.state[1] = x ^ y ^ (x >> 17) ^ (y >> 26);
+
+        // Generate the final integer.
+        self.state[1].wrapping_add(y)
+
     }
     fn fill_bytes(&mut self, buf: &mut [u8]) {
         for chunk in buf.chunks_mut(8) {

src/libstd/sys/redox/start.rs

@@ -0,0 +1,43 @@
+use sys::syscall::exit;
+
+#[allow(private_no_mangle_fns)]
+#[no_mangle]
+#[naked]
+#[cfg(target_arch = "x86")]
+pub unsafe fn _start() {
+    asm!("push esp
+        call _start_stack
+        pop esp"
+        :
+        :
+        : "memory"
+        : "intel", "volatile");
+    let _ = exit(0);
+}
+
+#[allow(private_no_mangle_fns)]
+#[no_mangle]
+#[naked]
+#[cfg(target_arch = "x86_64")]
+pub unsafe fn _start() {
+    asm!("mov rdi, rsp
+        and rsp, 0xFFFFFFFFFFFFFFF0
+        call _start_stack"
+        :
+        :
+        : "memory"
+        : "intel", "volatile");
+    let _ = exit(0);
+}
+
+#[allow(private_no_mangle_fns)]
+#[no_mangle]
+pub unsafe extern "C" fn _start_stack(stack: *const usize){
+    extern "C" {
+        fn main(argc: usize, argv: *const *const u8) -> usize;
+    }
+
+    let argc = *stack as usize;
+    let argv = stack.offset(1) as *const *const u8;
+    let _ = exit(main(argc, argv));
+}