Michael Bolin
b859a98e0f
## Why
The unified-exec path was carrying zsh-fork state in a partially
flattened way.
First, the decision about whether zsh-fork was active came from feature
selection in `ToolsConfig`, while the real prerequisites lived in
session state. That left the handler and runtime defending against
partially configured cases later.
Second, once zsh-fork was active, its two runtime-only paths were
threaded through the runtime as separate arguments even though they form
one coherent piece of configuration.
This change keeps unified-exec on a single session-derived source of
truth and bundles the zsh-fork-specific paths into a named config type
so the runtime can pass them around as one unit.
In particular, this PR introduces this enum so the `ZshFork` variant can
carry the appropriate state with it:
```rust
#[derive(Debug, Clone, Eq, PartialEq)]
pub enum UnifiedExecShellMode {
Direct,
ZshFork(ZshForkConfig),
}
#[derive(Debug, Clone, Eq, PartialEq)]
pub struct ZshForkConfig {
pub(crate) shell_zsh_path: AbsolutePathBuf,
pub(crate) main_execve_wrapper_exe: AbsolutePathBuf,
}
```
This cleanup was done in preparation for
https://github.com/openai/codex/pull/13432.
## What Changed
- Replaced the feature-only `UnifiedExecBackendConfig` split with
`UnifiedExecShellMode` in `codex-rs/core/src/tools/spec.rs`.
- Derived the unified-exec mode from session-backed inputs when building
turn `ToolsConfig`, and preserved that mode across model switches and
review turns.
- Introduced `ZshForkConfig`, which stores the resolved zsh-fork
`AbsolutePathBuf` values for the configured `zsh` binary and `execve`
wrapper.
- Threaded `ZshForkConfig` through unified-exec command construction and
the zsh-fork preparation path so zsh-fork-specific runtime code consumes
a single config object instead of separate path arguments.
- Added focused tests for constructing zsh-fork mode only when session
prerequisites are available, and updated the zsh-fork expectations to be
target-platform aware.
## Testing
- `cargo test -p codex-core zsh_fork --lib`
---
[//]: # (BEGIN SAPLING FOOTER)
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* #13432
* __->__ #14633
codex-core
This crate implements the business logic for Codex. It is designed to be used by the various Codex UIs written in Rust.
Dependencies
Note that codex-core makes some assumptions about certain helper utilities being available in the environment. Currently, this support matrix is:
macOS
Expects /usr/bin/sandbox-exec to be present.
When using the workspace-write sandbox policy, the Seatbelt profile allows
writes under the configured writable roots while keeping .git (directory or
pointer file), the resolved gitdir: target, and .codex read-only.
Network access and filesystem read/write roots are controlled by
SandboxPolicy. Seatbelt consumes the resolved policy and enforces it.
Seatbelt also supports macOS permission-profile extensions layered on top of
SandboxPolicy:
- no extension profile provided:
keeps legacy default preferences read access (
user-preference-read). - extension profile provided with no
macos_preferencesgrant: does not add preferences access clauses. macos_preferences = "readonly": enables cfprefs read clauses anduser-preference-read.macos_preferences = "readwrite": includes readonly clauses plususer-preference-writeand cfprefs shm write clauses.macos_automation = true: enables broad Apple Events send permissions.macos_automation = ["com.apple.Notes", ...]: enables Apple Events send only to listed bundle IDs.macos_launch_services = true: enables LaunchServices lookups and open/launch operations.macos_accessibility = true: enablescom.apple.axservermach lookup.macos_calendar = true: enablescom.apple.CalendarAgentmach lookup.macos_contacts = "read_only": enables Address Book read access and Contacts read services.macos_contacts = "read_write": includes the readonly Contacts clauses plus Address Book writes and keychain/temp helpers required for writes.
Linux
Expects the binary containing codex-core to run the equivalent of codex sandbox linux (legacy alias: codex debug landlock) when arg0 is codex-linux-sandbox. See the codex-arg0 crate for details.
Legacy SandboxPolicy / sandbox_mode configs are still supported on Linux.
They can continue to use the legacy Landlock path when the split filesystem
policy is sandbox-equivalent to the legacy model after cwd resolution.
Split filesystem policies that need direct FileSystemSandboxPolicy
enforcement, such as read-only or denied carveouts under a broader writable
root, automatically route through bubblewrap. The legacy Landlock path is used
only when the split filesystem policy round-trips through the legacy
SandboxPolicy model without changing semantics. That includes overlapping
cases like /repo = write, /repo/a = none, /repo/a/b = write, where the
more specific writable child must reopen under a denied parent.
All Platforms
Expects the binary containing codex-core to simulate the virtual apply_patch CLI when arg1 is --codex-run-as-apply-patch. See the codex-arg0 crate for details.