Begin work on supporting wasm32 architecture

core/os/os_js_wasm32.odin

@@ -0,0 +1,68 @@
+package os
+
+OS :: "js";
+
+
+Handle :: distinct i32;
+Errno :: distinct i32;
+
+ERROR_NONE :: Errno(0);
+
+O_RDONLY   :: 0x00000;
+O_WRONLY   :: 0x00001;
+O_RDWR     :: 0x00002;
+O_CREATE   :: 0x00040;
+O_EXCL     :: 0x00080;
+O_NOCTTY   :: 0x00100;
+O_TRUNC    :: 0x00200;
+O_NONBLOCK :: 0x00800;
+O_APPEND   :: 0x00400;
+O_SYNC     :: 0x01000;
+O_ASYNC    :: 0x02000;
+O_CLOEXEC  :: 0x80000;
+
+stdout: Handle;
+stderr: Handle;
+stdin: Handle;
+
+
+write :: proc(fd: Handle, data: []byte) -> (int, Errno) {
+	return 0, 0;
+}
+read :: proc(fd: Handle, data: []byte) -> (int, Errno) {
+	return 0, 0;
+}
+open :: proc(path: string, mode: int = O_RDONLY, perm: int = 0) -> (Handle, Errno) {
+	return 0, 0;
+}
+close :: proc(fd: Handle) -> Errno {
+	return 0;
+}
+
+
+current_thread_id :: proc "contextless" () -> int {
+	return 0;
+}
+
+
+file_size :: proc(fd: Handle) -> (i64, Errno) {
+	return 0, 0;
+}
+
+
+
+heap_alloc :: proc(size: int) -> rawptr {
+	return nil;
+}
+heap_resize :: proc(ptr: rawptr, new_size: int) -> rawptr {
+	if new_size == 0 {
+		heap_free(ptr);
+		return nil;
+	}
+	if ptr == nil do return heap_alloc(new_size);
+
+	return nil;
+}
+heap_free :: proc(ptr: rawptr) {
+	if ptr == nil do return;
+}

core/runtime/procs_wasm32.odin

@@ -0,0 +1,14 @@
+package runtime
+
+@(link_name="memset")
+memset :: proc "c" (ptr: rawptr, val: i32, len: int) -> rawptr {
+	b := byte(val);
+
+	p_start := uintptr(ptr);
+	p_end := p_start + uintptr(max(len, 0));
+	for p := p_start; p < p_end; p += 1 {
+		(^byte)(p)^ = b;
+	}
+
+	return ptr;
+}