fix(task): use shared memory for fspy ipc

[branchseer]

Implemented a shared memory IPC channel for fspy to improve performance and reliability when tracking file system accesses.

The channel implementation is cross-platform. In this PR it's only adopted in macOS/Linux version of fspy​. Windows version of fspy​ will switch to it in a separate PR.

Why make this change?

The previous IPC implementation uses file descriptor inheritance to pass down the IPC channel. It has the risk of descriptors being closed in the child processes. Some defensive logic was implemented to handle it, including:

• Increase the fd number to avoid Node.js closing small fds:

  vite-plus/crates/fspy/src/unix/mod.rs

  Line 156 in 540f597

  fn duplicate_until_safe(mut fd: OwnedFd) -> io::Result<OwnedFd> {

• Intercept posix_spawn​ to avoid being closed by POSIX_SPAWN_CLOEXEC_DEFAULT​:

  vite-plus/crates/fspy_preload_unix/src/client/mod.rs

  Line 208 in 540f597

  pub unsafe fn handle_posix_spawn_opts(

It apparently missed some cases, and the IPC fd still got closed, leading to bad descriptor​ error in https://github.com/voidzero-dev/vibe-dashboard/actions/runs/18532354385/job/52818262992.

What changed?

• Created a new shared memory-based IPC channel implementation for fspy that replaces the previous Unix socket approach.
  • The shared memory is looked up based on names instead of descriptors, making it impossible to be unexpectedly closed in child processes.
  • Proper file locking is added to ensure safe access to shared memory
  • Writing to the IPC channel becomes much faster as it now only does some atomic memory operations and doesn't trigger any syscalls.
• Modified the semantics of fs access tracking:
  • The previous implementation automatically waits for the root target process and all its descendants to exit due to the nature of file descriptor inheritance.
  • The new implementation requires waiting accesses_future after the root target process has exited. If descendants are spawned after the root target process has exited, their fs accesses will be missed.

---

Note

Replaces Unix fspy IPC with a lock-backed shared-memory channel and updates payloads, readers, and callers; adds test utils and adjusts env/TLS dependencies.

• IPC (core):
  • Introduces shared-memory IPC (fspy_shared::ipc::channel) with Sender/Receiver and lock-guarded ShmReader/ShmWriter for zero-syscall writes.
• fspy (Unix/macOS):
  • Switches from FD/Unix-socket IPC to shared memory; payload now carries ChannelConf instead of an FD.
  • Refactors SpyInner::init_in, fixture handling, and path injection; reads frames via shared memory; lazy-locks receiver after child exit.
• Preload (Unix):
  • Client sends PathAccess via shared memory; removes POSIX spawn FD-inheritance handling; minor argv handling fix.
• Windows:
  • Keeps pipe IPC; small fix to NativeStr construction and a temporary task to avoid blocking.
• API/Semantics & Callers:
  • accesses_future must be awaited after child exit; updates examples, tests, e2e, and vite_task execution flow accordingly.
  • Adds fspy_test_utils crate for cross-process test helpers.
• Shared types:
  • Enhances NativeStr/NativeString for zero-copy (ANSI/wide) and cross-platform encoding; updates spawn payload/env usage.
• Dependencies:
  • Adds shared_memory, memmap2, uuid, tracing; tweaks nix features; switches reqwest to native-tls-vendored (adds openssl-src).
• Misc:
  • Cleans up obsolete files and adjusts test steps (platform filters).

^{Written by Cursor Bugbot for commit 8f35015. This will update automatically on new commits. Configure here.}

[branchseer]

• chore(fspy): remove ignoring Chromium processes #249
• refactor(fspy): use shared memory IPC on Windows #239
• fix(task): use shared memory for fspy ipc #234 👈 (View in Graphite)
• test: add test for vitest browser mode #235
• main

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[Copilot]

Pull Request Overview

This PR transitions the fspy IPC mechanism from file descriptor-based communication to a shared memory-based channel implementation. The change improves reliability and cross-platform compatibility by using shared memory for inter-process communication instead of passing file descriptors.

Key changes:

• Implements a new lock-free shared memory writer/reader system
• Replaces FD-passing IPC with shared memory channels
• Removes Linux-specific memfd implementation in favor of unified filesystem-based approach

Reviewed Changes

Copilot reviewed 30 out of 31 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/cli/snap-tests/vitest-browser-mode/steps.json	Removes Linux from ignored platforms for browser mode tests
fspy/node_spawn.mjs	Removes temporary test file
fspy/.gitignore	Removes gitignore file
crates/vite_task/src/execute.rs	Changes task execution to await path accesses after child completion instead of concurrently
crates/fspy_test_utils/src/lib.rs	Adds new test utility crate for creating subprocess commands with encoded arguments
crates/fspy_test_utils/README.md	Adds documentation for fspy_test_utils
crates/fspy_test_utils/Cargo.toml	Adds dependencies for the test utilities crate
crates/fspy_shared_unix/src/spawn/macos.rs	Updates to use as_os_str() method for path conversions
crates/fspy_shared_unix/src/spawn/linux/mod.rs	Updates to use as_os_str() method for path conversions
crates/fspy_shared_unix/src/payload.rs	Replaces ipc_fd with ipc_channel_conf in payload structure
crates/fspy_shared/src/ipc/shm/mod.rs	Removes placeholder TODO file
crates/fspy_shared/src/ipc/native_str.rs	Enhances NativeString to support both Unix and Windows platforms with improved API
crates/fspy_shared/src/ipc/mod.rs	Updates module structure to include channel and export NativeString unconditionally
crates/fspy_shared/src/ipc/channel/shm_io.rs	Implements lock-free concurrent shared memory writer and reader
crates/fspy_shared/src/ipc/channel/mod.rs	Implements mpsc IPC channel based on shared memory
crates/fspy_shared/Cargo.toml	Adds dependencies for shared memory and IPC channel functionality
crates/fspy_preload_windows/src/windows/detours/create_process.rs	Updates to use from_ansi method for Windows ANSI strings
crates/fspy_preload_unix/src/interceptions/spawn/posix_spawn.rs	Removes unused posix_spawn file actions handling and variables
crates/fspy_preload_unix/src/interceptions/spawn/exec/with_argv.rs	Fixes type inconsistency in pointer type annotation
crates/fspy_preload_unix/src/client/mod.rs	Replaces shared memory FD-passing IPC with channel-based implementation
crates/fspy_e2e/src/main.rs	Changes to await accesses_future after child completion
crates/fspy/tests/test_utils.rs	Changes to await accesses_future after child completion
crates/fspy/tests/node_fs.rs	Changes to await accesses_future after child completion
crates/fspy/src/unix/mod.rs	Replaces FD-passing IPC with shared memory channel implementation
crates/fspy/src/lib.rs	Simplifies Spy initialization by using filesystem-based approach for all platforms
crates/fspy/src/fixture.rs	Adds conditional compilation for unused fixture method
crates/fspy/examples/cli.rs	Changes to await child completion before accessing results
crates/fspy/Cargo.toml	Adds dependencies for fixture creation on all platforms
bench/Cargo.toml	Reorders dependencies alphabetically
Cargo.toml	Adds fspy_test_utils workspace member and updates reqwest features

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Pull Request Overview

Copilot reviewed 30 out of 31 changed files in this pull request and generated 3 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 30 out of 31 changed files in this pull request and generated 1 comment.

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Pull Request Overview

Copilot reviewed 30 out of 31 changed files in this pull request and generated no new comments.

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