fix: memory leak (#29)

Memory leak was caused by
rustwasm/wee_alloc#106. This PR fixes the leak
by removes lightweight allocator

I have also added a test, which is now disabled, that hashes 17GB in a
loop to verify expected memory use. Test is disabled because it takes a
long time to run.

cargo.toml

@@ -8,7 +8,7 @@ edition = "2018"
 crate-type = ["cdylib", "rlib"]
 
 [features]
-default = ["console_error_panic_hook", "wee_alloc"]
+default = ["console_error_panic_hook"]
 
 [dependencies]
 wasm-bindgen = "0.2.84"
@@ -20,12 +20,6 @@ unsigned-varint = "0.7.2"
 # code size when deploying.
 console_error_panic_hook = { version = "0.1.6", optional = true }
 
-# `wee_alloc` is a tiny allocator for wasm that is only ~1K in code size
-# compared to the default allocator's ~10K. It is slower than the default
-# allocator, however.
-#
-# Unfortunately, `wee_alloc` requires nightly Rust when targeting wasm for now.
-wee_alloc = { version = "0.4.5", optional = true }
 web-sys = { version = "0.3.61", features = [
   "console",
   "Window",

gen/wasm.d.ts

@@ -48,12 +48,13 @@ export interface InitOutput {
   readonly __wbg_piecehasher_free: (a: number) => void;
   readonly piecehasher_count: (a: number) => number;
   readonly piecehasher_reset: (a: number) => void;
-  readonly piecehasher_write: (a: number, b: number, c: number) => void;
+  readonly piecehasher_write: (a: number, b: number, c: number, d: number) => void;
   readonly piecehasher_digestInto: (a: number, b: number, c: number, d: number, e: number, f: number, g: number) => number;
   readonly piecehasher_digestByteLength: (a: number) => number;
   readonly piecehasher_multihashByteLength: (a: number) => number;
   readonly create: () => number;
   readonly piecehasher_create: () => number;
+  readonly __wbindgen_add_to_stack_pointer: (a: number) => number;
   readonly __wbindgen_malloc: (a: number, b: number) => number;
 }
 

gen/wasm.js

@@ -1,20 +1,6 @@
 // @ts-nocheck
 let wasm;
 
-let cachedUint8Memory0 = null;
-
-function getUint8Memory0() {
-    if (cachedUint8Memory0 === null || cachedUint8Memory0.byteLength === 0) {
-        cachedUint8Memory0 = new Uint8Array(wasm.memory.buffer);
-    }
-    return cachedUint8Memory0;
-}
-
-function getArrayU8FromWasm0(ptr, len) {
-    ptr = ptr >>> 0;
-    return getUint8Memory0().subarray(ptr / 1, ptr / 1 + len);
-}
-
 const heap = new Array(128).fill(undefined);
 
 heap.push(undefined, null, true, false);
@@ -35,6 +21,20 @@ function takeObject(idx) {
     return ret;
 }
 
+let cachedUint8Memory0 = null;
+
+function getUint8Memory0() {
+    if (cachedUint8Memory0 === null || cachedUint8Memory0.byteLength === 0) {
+        cachedUint8Memory0 = new Uint8Array(wasm.memory.buffer);
+    }
+    return cachedUint8Memory0;
+}
+
+function getArrayU8FromWasm0(ptr, len) {
+    ptr = ptr >>> 0;
+    return getUint8Memory0().subarray(ptr / 1, ptr / 1 + len);
+}
+
 const cachedTextDecoder = (typeof TextDecoder !== 'undefined' ? new TextDecoder('utf-8', { ignoreBOM: true, fatal: true }) : { decode: () => { throw Error('TextDecoder not available') } } );
 
 if (typeof TextDecoder !== 'undefined') { cachedTextDecoder.decode(); };
@@ -53,6 +53,15 @@ function passArray8ToWasm0(arg, malloc) {
     return ptr;
 }
 
+let cachedInt32Memory0 = null;
+
+function getInt32Memory0() {
+    if (cachedInt32Memory0 === null || cachedInt32Memory0.byteLength === 0) {
+        cachedInt32Memory0 = new Int32Array(wasm.memory.buffer);
+    }
+    return cachedInt32Memory0;
+}
+
 function addHeapObject(obj) {
     if (heap_next === heap.length) heap.push(heap.length + 1);
     const idx = heap_next;
@@ -120,9 +129,19 @@ export class PieceHasher {
     * @param {Uint8Array} bytes
     */
     write(bytes) {
-        const ptr0 = passArray8ToWasm0(bytes, wasm.__wbindgen_malloc);
-        const len0 = WASM_VECTOR_LEN;
-        wasm.piecehasher_write(this.__wbg_ptr, ptr0, len0);
+        try {
+            const retptr = wasm.__wbindgen_add_to_stack_pointer(-16);
+            const ptr0 = passArray8ToWasm0(bytes, wasm.__wbindgen_malloc);
+            const len0 = WASM_VECTOR_LEN;
+            wasm.piecehasher_write(retptr, this.__wbg_ptr, ptr0, len0);
+            var r0 = getInt32Memory0()[retptr / 4 + 0];
+            var r1 = getInt32Memory0()[retptr / 4 + 1];
+            if (r1) {
+                throw takeObject(r0);
+            }
+        } finally {
+            wasm.__wbindgen_add_to_stack_pointer(16);
+        }
     }
     /**
     * @param {Uint8Array} target
@@ -186,11 +205,15 @@ async function __wbg_load(module, imports) {
 function __wbg_get_imports() {
     const imports = {};
     imports.wbg = {};
+    imports.wbg.__wbindgen_object_drop_ref = function(arg0) {
+        takeObject(arg0);
+    };
     imports.wbg.__wbindgen_copy_to_typed_array = function(arg0, arg1, arg2) {
         new Uint8Array(getObject(arg2).buffer, getObject(arg2).byteOffset, getObject(arg2).byteLength).set(getArrayU8FromWasm0(arg0, arg1));
     };
-    imports.wbg.__wbindgen_object_drop_ref = function(arg0) {
-        takeObject(arg0);
+    imports.wbg.__wbg_new_d258248ed531ff54 = function(arg0, arg1) {
+        const ret = new Error(getStringFromWasm0(arg0, arg1));
+        return addHeapObject(ret);
     };
     imports.wbg.__wbindgen_throw = function(arg0, arg1) {
         throw new Error(getStringFromWasm0(arg0, arg1));
@@ -206,6 +229,7 @@ function __wbg_init_memory(imports, maybe_memory) {
 function __wbg_finalize_init(instance, module) {
     wasm = instance.exports;
     __wbg_init.__wbindgen_wasm_module = module;
+    cachedInt32Memory0 = null;
     cachedUint8Memory0 = null;
 
 

gen/wasm_bg.wasm.d.ts

@@ -4,10 +4,11 @@ export const memory: WebAssembly.Memory;
 export function __wbg_piecehasher_free(a: number): void;
 export function piecehasher_count(a: number): number;
 export function piecehasher_reset(a: number): void;
-export function piecehasher_write(a: number, b: number, c: number): void;
+export function piecehasher_write(a: number, b: number, c: number, d: number): void;
 export function piecehasher_digestInto(a: number, b: number, c: number, d: number, e: number, f: number, g: number): number;
 export function piecehasher_digestByteLength(a: number): number;
 export function piecehasher_multihashByteLength(a: number): number;
 export function create(): number;
 export function piecehasher_create(): number;
+export function __wbindgen_add_to_stack_pointer(a: number): number;
 export function __wbindgen_malloc(a: number, b: number): number;

package.json

@@ -55,7 +55,8 @@
   },
   "c8": {
     "exclude": [
-      "gen/**"
+      "gen/**",
+      "test/**"
     ]
   },
   "devDependencies": {