1 files changed, 72 insertions, 0 deletions
diff --git a/vendor/dlmalloc/src/wasm.rs b/vendor/dlmalloc/src/wasm.rs
new file mode 100644
index 000000000..216fe43af
--- /dev/null
+++ b/vendor/dlmalloc/src/wasm.rs
@@ -0,0 +1,72 @@
+#[cfg(target_arch = "wasm32")]
+use core::arch::wasm32 as wasm;
+#[cfg(target_arch = "wasm64")]
+use core::arch::wasm64 as wasm;
+use core::ptr;
+use Allocator;
+
+/// System setting for Wasm
+pub struct System {
+    _priv: (),
+}
+
+impl System {
+    pub const fn new() -> System {
+        System { _priv: () }
+    }
+}
+
+unsafe impl Allocator for System {
+    fn alloc(&self, size: usize) -> (*mut u8, usize, u32) {
+        let pages = size / self.page_size();
+        let prev = wasm::memory_grow(0, pages);
+        if prev == usize::max_value() {
+            return (ptr::null_mut(), 0, 0);
+        }
+        (
+            (prev * self.page_size()) as *mut u8,
+            pages * self.page_size(),
+            0,
+        )
+    }
+
+    fn remap(&self, _ptr: *mut u8, _oldsize: usize, _newsize: usize, _can_move: bool) -> *mut u8 {
+        // TODO: I think this can be implemented near the end?
+        ptr::null_mut()
+    }
+
+    fn free_part(&self, _ptr: *mut u8, _oldsize: usize, _newsize: usize) -> bool {
+        false
+    }
+
+    fn free(&self, _ptr: *mut u8, _size: usize) -> bool {
+        false
+    }
+
+    fn can_release_part(&self, _flags: u32) -> bool {
+        false
+    }
+
+    fn allocates_zeros(&self) -> bool {
+        true
+    }
+
+    fn page_size(&self) -> usize {
+        64 * 1024
+    }
+}
+
+#[cfg(feature = "global")]
+pub fn acquire_global_lock() {
+    // single threaded, no need!
+}
+
+#[cfg(feature = "global")]
+pub fn release_global_lock() {
+    // single threaded, no need!
+}
+
+#[cfg(feature = "global")]
+pub unsafe fn enable_alloc_after_fork() {
+    // single threaded, no need!
+}