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Allow object references when decoding binary JSON (part of #275) - #281

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jackkav wants to merge 9 commits into
justjake:mainfrom
jackkav:fix-bjson-references
Open

jackkav wants to merge 9 commits into
justjake:mainfrom
jackkav:fix-bjson-references

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@jackkav jackkav commented Oct 16, 2026 •

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Layer: C interface (c/interface.c)
Review just this PR: jackkav/quickjs-emscripten@fix-c-null-checks...fix-bjson-references
Stack: #248 → #276 → #277 → (#278 | #279 → #280 → #281 → #282). Issues: #274, #275.

What

  • QTS_bjson_encode writes with JS_WRITE_OBJ_REFERENCE, but QTS_bjson_decode read with flags 0, so shared and cyclic objects encoded and then failed to decode (object references are not allowed). Decode now passes JS_READ_OBJ_REFERENCE. Bytecode and SharedArrayBuffer stay disallowed.

Test: 4 round-trip tests (plain, shared reference, shared identity, cycle); the 3 reference tests fail on wasm built from main and pass with the change, on quickjs and quickjs-ng.
Verified on: Full suite on freshly built wasm for every variant in the test matrix (sync/async × release/debug × quickjs/quickjs-ng) at the top of the stack (#282): 751 passed, 0 failed. Debug builds run the leak sanitizer check in afterAll.
Behavior change: Data with shared/cyclic references now decodes (it used to throw).
Overlap: No overlap with #207 beyond possible textual conflicts in c/interface.c.

🤖 Generated with Claude Code

justjake and others added 9 commits October 15, 2026 20:35
When Emscripten's WASM memory grows (due to -sALLOW_MEMORY_GROWTH), all
existing TypedArray views become detached because the underlying
ArrayBuffer is replaced. This caused bugs where reading from views after
FFI calls returned undefined values if memory had grown.

The fix introduces RefreshableTypedArray, a wrapper that lazily recreates
the TypedArray view when HEAPU8.buffer changes. This is a simple reference
comparison that only triggers view recreation when actually needed.

Affected call sites:
- runtime.ts: executePendingJobs - reads ctxPtrOut after QTS_ExecutePendingJob
- context.ts: newPromise - reads resolve/reject handles after QTS_NewPromiseCapability
- context.ts: getLength - reads uint32Out after QTS_GetLength
- context.ts: getOwnPropertyNames - reads outPtr and uint32Out after QTS_GetOwnPropertyNames

Also fixed: getOwnPropertyNames was using HEAP8.buffer instead of HEAPU8.buffer

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
- getArrayBuffer returned a HEAPU8.subarray view that is detached by the next
  WASM memory growth; return a copy instead.
- consumeJSCharPointer / consumeHeapCharPointer leaked the C string when
  UTF8ToString threw (e.g. strings longer than V8's max string length).
- newArrayBuffer leaked the host buffer (and returned an exception-tagged
  handle) when QuickJS failed to create the ArrayBuffer. It now frees the
  buffer and throws.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
…reelist

- ModuleMemory helpers now throw on a null _malloc instead of writing at address 0.
- getOwnPropertyNames freed a plain-malloc'd array with js_free (QTS_FreeVoidPointer),
  unbalancing QuickJS allocation counters; free it with the module's free.
- HostRefMap: FIFO freelist used Array#shift (quadratic when draining); use a head index.
  Deleting an already-deleted id in a non-empty group no longer queues it for reuse twice.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
…y arguments

- QTS_RuntimeDumpMemoryUsage wrote into a fixed 1 KiB fmemopen buffer, truncating the
  report mid-line once more than a few object kinds exist. Use open_memstream.
- QTS_Call built a variable-length array of argc values on the wasm shadow stack; a
  few hundred thousand arguments trapped the whole module. Heap allocate instead, and
  throw out-of-memory if that fails.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
…wnPropertyNames

- newContext (sync and asyncify) wrapped a NULL context pointer and carried on; throw.
- ContextMemory.heapValueHandle wrapped the NULL returned by jsvalue_to_heap when it
  cannot malloc; throw.
- QTS_GetOwnPropertyNames did not check its output malloc, and sized it per JSValue
  (8 bytes) instead of per JSValue* (4 bytes); check it, free the property atoms and
  throw out-of-memory on failure.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
QTS_bjson_encode writes with JS_WRITE_OBJ_REFERENCE so shared and cyclic objects
encode, but QTS_bjson_decode read with flags 0, so decoding them failed with
"object references are not allowed". Pass JS_READ_OBJ_REFERENCE. Bytecode and
SharedArrayBuffer remain disallowed.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
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