Implement malloc/free with ralloc

stdlib/src/lib.rs

@@ -0,0 +1,64 @@
+//! stdlib implementation for Redox, following http://pubs.opengroup.org/onlinepubs/7908799/xsh/stdlib.h.html
+
+#![no_std]
+#![feature(global_allocator)]
+
+extern crate platform;
+extern crate ralloc;
+
+use platform::types::*;
+
+#[global_allocator]
+static ALLOCATOR: ralloc::Allocator = ralloc::Allocator;
+
+pub const EXIT_FAILURE: c_int = 1;
+pub const EXIT_SUCCESS: c_int = 0;
+
+static mut ATEXIT_FUNCS: [usize; 32] = [0; 32];
+
+#[no_mangle]
+pub unsafe extern "C" fn atexit(func: extern "C" fn()) -> c_int {
+    for i in 0..ATEXIT_FUNCS.len() {
+        if ATEXIT_FUNCS[i] == 0 {
+            ATEXIT_FUNCS[i] = func as usize;
+            return 0;
+        }
+    }
+
+    1
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn exit(status: c_int) {
+    use core::mem;
+
+    for i in (0..ATEXIT_FUNCS.len()).rev() {
+        if ATEXIT_FUNCS[i] != 0 {
+            let func = mem::transmute::<usize, extern "C" fn()>(ATEXIT_FUNCS[i]);
+            (func)();
+        }
+    }
+
+    platform::exit(status);
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn free(ptr: *mut c_void) {
+    let ptr = (ptr as *mut u8).offset(-8);
+    let size = *(ptr as *mut u64);
+    ralloc::free(ptr, size as usize);
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn malloc(size: size_t) -> *mut c_void {
+    let ptr = ralloc::alloc(size + 8, 8);
+    *(ptr as *mut u64) = size as u64;
+    ptr.offset(8) as *mut c_void
+}
+
+/*
+#[no_mangle]
+pub extern "C" fn func(args) -> c_int {
+    unimplemented!();
+}
+*/