Modularise the wasm module by a1q123456 · Pull Request #6441 · XRPLF/rippled

a1q123456 · 2026-02-26T18:09:37Z

High Level Overview of Change

This PR modularises the WASM module to make it possible to call wasm from transactors after transactor modularisation.

Context of Change

Type of Change

Bug fix (non-breaking change which fixes an issue)
New feature (non-breaking change which adds functionality)
Breaking change (fix or feature that would cause existing functionality to not work as expected)
Refactor (non-breaking change that only restructures code)
Performance (increase or change in throughput and/or latency)
Tests (you added tests for code that already exists, or your new feature included in this PR)
Documentation update
Chore (no impact to binary, e.g. .gitignore, formatting, dropping support for older tooling)
Release

API Impact

Public API: New feature (new methods and/or new fields)
Public API: Breaking change (in general, breaking changes should only impact the next api_version)
libxrpl change (any change that may affect libxrpl or dependents of libxrpl)
Peer protocol change (must be backward compatible or bump the peer protocol version)

Signed-off-by: JCW <a1q123456@users.noreply.github.com>

sappenin · 2026-02-26T18:17:36Z

include/xrpl/tx/transactors/smart_escrow/wasm/WasmEngine.h

 #pragma once

-#include <xrpld/app/wasm/HostFunc.h>
+#include <xrpl/tx/transactors/smart_escrow/HostFunc.h>


Smart Escrow is just one feature, wheras the WASM VM will power multiple "Smart Features." Because of that, I think may <xrpl/tx/transactors/wasm/HostFunc.h> is the better location?

Do we want it to be in the transactors module or a separate module entirely?

My idea was, once we want to use wasm for something else, we take the smart_escrow/wasm folder and make it a top level module like xrpl.wasm and then we implement other things for that feature specifically.

HostFunc is something tightly coupled with smart escrow and I don't think we'll reuse it.

HostFunc is something tightly coupled with smart escrow and I don't think we'll reuse it.

Actually, HostFunctions are coupled to the broader category of Smart Features (with more coming soon), not just Smart Escrow.

Smart Escrow serves as a proving ground for generalized WASM functionality in xrpld. Future WASM-based features—like Smart Features, Smart Contracts, potentially even Native Transactors—will reuse this layer.

Ultimately, WASM should be viewed as a cross-cutting architectural feature that may even extend beyond transactor processing.

sappenin · 2026-02-26T18:18:11Z

include/xrpl/tx/transactors/smart_escrow/README.md

 ```
 ┌─────────────────────────────────────────────────────────────┐
-│                 WasmEngine (WasmVM.h)                       │
+│                 EscrowWasm.h                                │


This is incorrect. The WasmEngine is not specific to Escrow (it's used by Escrow, but will be used by more in the future).

oleks-rip · 2026-02-26T19:15:35Z

include/xrpl/tx/transactors/smart_escrow/wasm/WasmEngine.h


 namespace xrpl {

+// Generic WASM constants


This comment explain / clarify nothing, I don't think we need to add obvious comments.

oleks-rip · 2026-02-26T19:22:51Z

include/xrpl/tx/transactors/smart_escrow/wasm/WasmEngine.h

 uint32_t const MAX_PAGES = 128;  // 8MB = 64KB*128

-class WasmiEngine;
+class WasmiRuntime;


I know choosing naming is tough process, so it need to be done in separate PR with proper discussion. For example "Runtime" is more suitable for javascript engine, wasm is more docker like.

Renaming it here just complicate reviewing modularization.

oleks-rip · 2026-02-26T19:23:45Z

include/xrpl/tx/transactors/smart_escrow/wasm/WasmEngine.h

+class WasmiRuntime;

+/**
+ * WasmEngine - Singleton facade for WASM runtime execution.


Same comment about renaming.

oleks-rip · 2026-02-26T19:23:51Z

include/xrpl/tx/transactors/smart_escrow/wasm/WasmEngine.h

 class WasmEngine
 {
-    std::unique_ptr<WasmiEngine> const impl;
+    std::unique_ptr<WasmiRuntime> const impl;


Same comment about renaming.

oleks-rip · 2026-02-26T19:25:04Z

include/xrpl/tx/transactors/smart_escrow/EscrowWasm.h

+ * @return Shared pointer to the import vector
+ */
+std::shared_ptr<ImportVec>
+createWasmImport(HostFunctions& hfs);


This doesn't belong to "Escrow", it is more general.

oleks-rip · 2026-02-26T19:30:03Z

include/xrpl/tx/transactors/smart_escrow/EscrowWasm.h

@@ -0,0 +1,65 @@
+#pragma once


Name EscrowWasm.h is more like some ledger object / transaction style. EscrowWasmHelpers.h more suitable

oleks-rip · 2026-02-26T19:34:46Z

src/libxrpl/tx/transactors/smart_escrow/EscrowWasm.cpp


-    // std::cout << "runEscrowWasm, mod size: " << wasmCode.size()
-    //           << ", gasLimit: " << gasLimit << ", funcName: " << funcName;
+#ifdef DEBUG_OUTPUT


Please use another definition, as it not always needed during debugging.

oleks-rip · 2026-02-26T19:38:17Z

src/libxrpl/tx/transactors/smart_escrow/wasm/WasmiRuntime.cpp

-WasmiEngine::allocate(int32_t sz)
+WasmiRuntime::allocate(int32_t sz)
 {
-    if (sz <= 0)


Why? You shouldn't remove security checks.

oleks-rip · 2026-02-26T19:39:37Z

src/libxrpl/tx/transactors/smart_escrow/wasm/WasmiRuntime.cpp

-        wasm_byte_vec_delete(&msg);
-
-    return trap;
+    wasm_message_t message;


Same here, why you remove security checks?

oleks-rip · 2026-02-26T19:41:19Z

src/libxrpl/tx/transactors/smart_escrow/wasm/WasmiRuntime.cpp

        gas = std::numeric_limits<decltype(gas)>::max();
    WasmResult<int32_t> const ret{res.r.vec_.data[0].of.i32, gas - moduleWrap_->getGas()};

-    // #ifdef DEBUG_OUTPUT


Coudl you please just put it into additional #ifdef section and not removing it.

mvadari · 2026-02-27T20:29:27Z

@a1q123456 can we focus on just the modularization in this PR, and not make any other changes? If you have other concerns/changes you want to make, we can discuss those separately, in PR review for #6075

Modularise the wasm module

072d800

Signed-off-by: JCW <a1q123456@users.noreply.github.com>

a1q123456 requested a review from mvadari February 26, 2026 18:09

a1q123456 changed the base branch from develop to ripple/wasmi-host-functions February 26, 2026 18:09

sappenin suggested changes Feb 26, 2026

View reviewed changes

mvadari requested review from mvadari, oleks-rip and pwang200 and removed request for mvadari February 26, 2026 18:20

oleks-rip reviewed Feb 26, 2026

View reviewed changes

Conversation

a1q123456 commented Feb 26, 2026

High Level Overview of Change

Context of Change

Type of Change

API Impact

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

a1q123456 Feb 26, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

sappenin Feb 26, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

oleks-rip Feb 26, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

mvadari commented Feb 27, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

a1q123456 Feb 26, 2026 •

edited

Loading

sappenin Feb 26, 2026 •

edited

Loading

oleks-rip Feb 26, 2026 •

edited

Loading

mvadari commented Feb 27, 2026 •

edited

Loading