old code was bad and wrong

.gitignore

@@ -1 +1,5 @@
 /target
+Cargo.lock
+elf2le
+a.exe
+new.elf

src/dpmi_alloc.rs

@@ -2,81 +2,11 @@ use core::{ptr::null_mut, arch::asm, alloc::Layout};
 use core::fmt::Write;
 use heapless::String;
 
-const PTR_COUNT: usize = 1024;
+pub struct DpmiAlloc {}
+impl DpmiAlloc { const fn new() -> Self { DpmiAlloc { } } }
 
-struct Locked<A> {
+unsafe impl core::alloc::GlobalAlloc for DpmiAlloc {
-    inner: spin::Mutex<A>,
-}
-impl<A> Locked<A> {
-    pub const fn new(inner: A) -> Self {
-        Locked {
-            inner: spin::Mutex::new(inner)
-        }
-    }
-    pub fn lock(&self) -> spin::MutexGuard<A> {
-        self.inner.lock()
-    }
-}
-
-pub fn init_allocator() { unsafe {
-    ALLOCATOR.inner.force_unlock();
-    let mut t = ALLOCATOR.lock();
-    //  3.53 - DOS function 0FF91h - DOS/32 Advanced Allocate High Memory Block
-    //  In: 	AX = 0FF91h
-    //  EBX = size of memory block in bytes
-    //  Out: 	
-    //  if successful:
-    //  CF clear
-    //  EBX = linear address of allocated memory block
-    //  ESI = handle of allocated memory block
-    //  if failed:
-    //  CF set
-    let ptr: u32;
-    let handle: u32;
-    asm!(
-        "mov edx, esi",
-        "int 0x21",
-        "mov eax, esi",
-        "mov esi, edx",
-        inout("eax") 0x0FF91 => handle,
-        inout("ebx") PTR_COUNT * core::mem::size_of::<DpmiPtr>() => ptr,
-        out("edx") _
-    );
-    t.ptrs = ptr;
-    t.global_handle = handle;
-    let mut ptrs = core::slice::from_raw_parts_mut::<DpmiPtr>(t.ptrs as *mut DpmiPtr, PTR_COUNT);
-    for p in ptrs.iter_mut() {
-        *p = DpmiPtr { ptr: 0, handle: 0 };
-    }
-} }
-
-#[derive(Copy, Clone)]
-struct DpmiPtr {
-    ptr: u32,
-    handle: u32
-}
-pub struct DpmiAlloc {
-    ptrs: u32,
-    global_handle: u32
-}
-impl DpmiAlloc {
-    const fn new() -> Self { DpmiAlloc { ptrs: 0, global_handle: 0 } }
-}
-
-unsafe impl core::alloc::GlobalAlloc for Locked<DpmiAlloc> {
     unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
-        let mut dat = self.lock();
-        let mut ptrs = unsafe { core::slice::from_raw_parts_mut::<DpmiPtr>(dat.ptrs as *mut DpmiPtr, PTR_COUNT) };
-        let free_idx: usize = {
-            let mut tmp = None;
-            for (i, p) in ptrs.iter().enumerate() {
-                if p.ptr == 0 { tmp = Some(i); break; }
-            }
-            match tmp {
-                None => { asm!("int 0x1", in("eax") ptrs.as_ptr()); return null_mut(); }
-                Some(i) => i
-            }
-        };
         //  3.53 - DOS function 0FF91h - DOS/32 Advanced Allocate High Memory Block
         //  In: 	AX = 0FF91h
         //  EBX = size of memory block in bytes
@@ -88,32 +18,21 @@ unsafe impl core::alloc::GlobalAlloc for Locked<DpmiAlloc> {
         //  if failed:
         //  CF set
         let ptr: u32;
-        let handle: u32;
+        let _handle: u32;
         asm!(
             "mov edx, esi",
             "int 0x21",
             "mov eax, esi",
             "mov esi, edx",
-            inout("eax") 0x0FF91 => handle,
+            inout("eax") 0x0FF91 => _handle,
             inout("ebx") layout.size() as u32 => ptr,
             out("edx") _
         );
-        ptrs[free_idx] = DpmiPtr { ptr, handle };
         ptr as *mut u8
     }
 
     unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) {
         if ptr as u32 == 0 { return; }
-        let mut dat = self.lock();
-        let mut ptrs = unsafe { core::slice::from_raw_parts_mut::<DpmiPtr>(dat.ptrs as *mut DpmiPtr, PTR_COUNT) };
-        let mut found_idx: Option<usize> = None;
-        for i in 0..ptrs.len() {
-            if ptrs[i].ptr == ptr as u32 { found_idx = Some(i); break; }
-        }
-        let handle = match found_idx {
-            None => return,
-            Some(i) => ptrs[i].handle
-        };
         //  3.54 - DOS function 0FF92h - DOS/32 Advanced Free High Memory Block
         //  In: 	AX = 0FF92h
         //  ESI = handle of previously allocated memory block
@@ -128,24 +47,13 @@ unsafe impl core::alloc::GlobalAlloc for Locked<DpmiAlloc> {
             "int 0x21",
             "mov esi, edx",
             in("eax") 0x0FF92,
-            in("ebx") handle,
+            in("ebx") ptr as u32 - 0x10, // handle should be just 0x10 less than the pointer
             out("edx") _
         );
-        ptrs[found_idx.unwrap()] = DpmiPtr { ptr: 0, handle: 0 };
     }
 
     unsafe fn realloc(&self, ptr: *mut u8, _layout: Layout, new_size: usize) -> *mut u8 {
         if ptr.is_null() { return null_mut(); }
-        let mut dat = self.lock();
-        let mut ptrs = core::slice::from_raw_parts_mut::<DpmiPtr>(dat.ptrs as *mut DpmiPtr, PTR_COUNT);
-        let mut found_idx: Option<usize> = None;
-        for i in 0..ptrs.len() {
-            if ptrs[i].ptr == ptr as u32 { found_idx = Some(i); break; }
-        }
-        let old_handle = match found_idx {
-            None => return null_mut(),
-            Some(i) => ptrs[i].handle
-        };
         //  3.55 - DOS function 0FF93h - DOS/32 Advanced Resize High Memory Block
         //  In: 	AX = 0FF93h
         //  EBX = new size of memory block in bytes
@@ -159,23 +67,22 @@ unsafe impl core::alloc::GlobalAlloc for Locked<DpmiAlloc> {
 
         //  if failed:
         //  CF set
-        let ptr: u32;
+        let new_ptr: u32;
-        let handle: u32;
+        let _handle: u32;
         asm!(
             "xchg edx, esi",
             "int 0x21",
             "xchg esi, edx",
             inout("eax") 0x0FF93 => _,
-            inout("ebx") new_size as u32 => ptr,
+            inout("ebx") new_size as u32 => new_ptr,
-            inout("edx") old_handle => handle
+            inout("edx") ptr as u32 - 0x10 => _handle
         );
-        ptrs[found_idx.unwrap()] = DpmiPtr { ptr, handle };
+        new_ptr as *mut u8
-        ptr as *mut u8
     }
 }
 
 #[global_allocator]
-static ALLOCATOR: Locked<DpmiAlloc> = Locked::new(DpmiAlloc::new());
+static ALLOCATOR: DpmiAlloc = DpmiAlloc::new();
 
 #[doc(hidden)]
 pub fn _print(args: core::fmt::Arguments) {