Porting mremap().

Author: anp

Cargo.toml

@@ -11,6 +11,7 @@ crate-type = ["staticlib", "dylib"]
 lazy_static = { version = "0.2.1", features = ["spin_no_std"] }
 rlibc = "1.0.0"
 syscall = "0.2.1"
+va_list = "0.0.3"
 
 [profile.release]
 debug = true

musl/src/mman/mremap.c

@@ -1,11 +1,13 @@
 #![no_std]
 #![feature(asm, lang_items, linkage)]
+//#![needs_panic_runtime]
 
 #![allow(non_camel_case_types)]
 
 #[macro_use]
 extern crate lazy_static;
 extern crate syscall;
+extern crate va_list;
 
 #[macro_use]
 pub mod syscall_mgt;
@@ -65,16 +67,10 @@ pub mod signal {
     pub use platform::signal::*;
 }
 
-#[lang = "eh_personality"]
+/*#[lang = "eh_personality"]
 extern "C" fn eh_personality() {}
 
 #[lang = "panic_fmt"]
 fn panic_fmt() -> ! {
     loop {}
-}
-
-#[cfg(test)]
-mod test {
-    #[test]
-    fn it_works() {}
-}
+}*/

src/lib.rs

@@ -1,5 +1,7 @@
 use core::isize;
 
+use va_list::VaList;
+
 use c_types::*;
 use errno::{set_errno, EINVAL, ENOMEM};
 use platform::mman::*;
@@ -37,6 +39,29 @@ pub unsafe extern "C" fn __mmap(start: *mut c_void,
     syscall!(MMAP, start, len, prot, flags, fd, off) as *mut c_void
 }
 
+#[no_mangle]
+pub unsafe extern "C" fn __mremap(old_address: *mut c_void,
+                                  old_len: size_t,
+                                  new_len: size_t,
+                                  flags: c_int,
+                                  mut args: VaList)
+                                  -> *mut c_void {
+
+    let mut new_address = 0 as *mut c_void;
+
+    if new_len >= isize::MAX as usize {
+        set_errno(ENOMEM);
+        return MAP_FAILED;
+    }
+
+    if flags & MREMAP_FIXED != 0 {
+        __vm_wait();
+        new_address = args.get::<usize>() as *mut c_void;
+    }
+
+    syscall!(MREMAP, old_address, old_len, new_len, flags, new_address) as *mut c_void
+}
+
 #[no_mangle]
 pub unsafe extern "C" fn madvise(address: *mut c_void, len: usize, advice: c_int) -> c_int {
     syscall!(MADVISE, address, len, advice) as c_int
@@ -86,3 +111,13 @@ pub unsafe extern "C" fn mmap64(start: *mut c_void,
                                 -> *mut c_void {
     __mmap(start, len, prot, flags, fd, off)
 }
+
+#[no_mangle]
+pub unsafe extern "C" fn mremap(old_address: *mut c_void,
+                                old_len: size_t,
+                                new_len: size_t,
+                                flags: c_int,
+                                args: VaList)
+                                -> *mut c_void {
+    __mremap(old_address, old_len, new_len, flags, args)
+}

src/mmap.rs

@@ -5,3 +5,4 @@ pub const PAGE_SIZE: off_t = 4096;
 pub const MAP_FAILED: *mut c_void = 0xffffffffffffffff as *mut c_void;
 
 pub const MAP_FIXED: c_int = 0x10;
+pub const MREMAP_FIXED: c_int = 2;