vendor/dlmalloc/src/macos.rs

   1 extern crate libc;
   2
   3 use core::ptr;
   4
   5 pub unsafe fn alloc(size: usize) -> (*mut u8, usize, u32) {
   6     let addr = libc::mmap(
   7         0 as *mut _,
   8         size,
   9         libc::PROT_WRITE | libc::PROT_READ,
  10         libc::MAP_ANON | libc::MAP_PRIVATE,
  11         -1,
  12         0,
  13     );
  14     if addr == libc::MAP_FAILED {
  15         (ptr::null_mut(), 0, 0)
  16     } else {
  17         (addr as *mut u8, size, 0)
  18     }
  19 }
  20
  21 pub unsafe fn remap(_ptr: *mut u8, _oldsize: usize, _newsize: usize, _can_move: bool) -> *mut u8 {
  22     ptr::null_mut()
  23 }
  24
  25 pub unsafe fn free_part(ptr: *mut u8, oldsize: usize, newsize: usize) -> bool {
  26     libc::munmap(ptr.offset(newsize as isize) as *mut _, oldsize - newsize) == 0
  27 }
  28
  29 pub unsafe fn free(ptr: *mut u8, size: usize) -> bool {
  30     libc::munmap(ptr as *mut _, size) == 0
  31 }
  32
  33 pub fn can_release_part(_flags: u32) -> bool {
  34     true
  35 }
  36
  37 #[cfg(feature = "global")]
  38 static mut LOCK: libc::pthread_mutex_t = libc::PTHREAD_MUTEX_INITIALIZER;
  39
  40 #[cfg(feature = "global")]
  41 pub fn acquire_global_lock() {
  42     unsafe { assert_eq!(libc::pthread_mutex_lock(&mut LOCK), 0) }
  43 }
  44
  45 #[cfg(feature = "global")]
  46 pub fn release_global_lock() {
  47     unsafe { assert_eq!(libc::pthread_mutex_unlock(&mut LOCK), 0) }
  48 }
  49
  50 pub fn allocates_zeros() -> bool {
  51     true
  52 }
  53
  54 pub fn page_size() -> usize {
  55     4096
  56 }