(Mirror) cli : Use acquire/release semantics for stopping logic

[ngxson]

@coderabbitai use mirror preset for review

mirror ggml-org#21822

Summary by CodeRabbit

• Bug Fixes

  • Improved interrupt (Ctrl+C) responsiveness and more reliable cancellation behavior
  • Double-interrupt now immediately exits with cleaner terminal output

• Performance

  • Simplified generation loop for more efficient and stable streaming output

• Other

  • Ensured cancellation state is correctly reset after generation or interactive cancellation

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: ffbd9262-7943-46e6-abff-832ab95033fc

📥 Commits

Reviewing files that changed from the base of the PR and between 3cdc177 and 07b8b2d.

📒 Files selected for processing (1)

• tools/cli/cli.cpp

🚧 Files skipped from review as they are similar to previous changes (1)

• tools/cli/cli.cpp

---

📝 Walkthrough

Walkthrough

Signal handling and interrupt state were refactored to use explicit atomic memory ordering and exchange semantics; the streaming generation loop condition was simplified; the stop flag is reset via a new reset function; cli_context::loading_show was removed.

Changes

Cohort / File(s)	Summary
CLI interrupt & loop tools/cli/cli.cpp	Reworked interrupt handling to use g_is_interrupted.exchange(true, std::memory_order_acq_rel) in the signal handler, should_stop() uses load(...memory_order_acquire), and a new reset_stop() uses store(...memory_order_release). Simplified streaming loop to while (result && !should_stop()) and replaced manual clears with reset_stop(). Removed cli_context::loading_show member.

Sequence Diagram(s)

sequenceDiagram
  participant User
  participant CLI as CLI Process
  participant Signal as OS Signal
  participant Gen as Generator Loop

  User->>CLI: Start generation
  CLI->>Gen: begin streaming generation
  Signal->>CLI: SIGINT/Ctrl+C
  CLI->>CLI: g_is_interrupted.exchange(true, memory_order_acq_rel)
  CLI->>Gen: should_stop()? (load memory_order_acquire)
  alt stop requested
    Gen->>CLI: stop loop (exit generation)
    CLI->>CLI: reset_stop() (store memory_order_release)
  else continue
    Gen->>Gen: continue streaming
  end
  CLI->>User: exit/cleanup

Loading

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

🐇 I thumped a key, the signal rang,

exchange and orders neatly sang,
The loop now checks and gently stops,
A reset clears the tiny hops,
I nibble code — concurrency snacks! 🥕

🚥 Pre-merge checks | ✅ 1 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description is missing critical sections from the template, including Overview (what/why), detailed AI usage disclosure, and the required contributing guidelines acknowledgment.	Expand description with Overview section explaining the changes and rationale, explicitly state AI usage (YES/NO), and add the required checklist acknowledging contributing guidelines.
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (1 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly describes the main change: refactoring the interrupt/stop mechanism to use acquire/release memory semantics in the CLI.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@tools/cli/cli.cpp`:
- Around line 46-53: The second-interrupt handler uses non-async-signal-safe
functions (fprintf, fflush, std::exit); change it to only call async-signal-safe
primitives: use g_is_interrupted.exchange as-is, then write(2) to STDOUT_FILENO
(or use a literal escape sequence buffer) to clear colors, and call _exit(130)
instead of std::exit; update the block that currently references
g_is_interrupted and the fprintf/fflush/std::exit sequence to use write(...) and
_exit(...) so the signal handler is POSIX async-signal-safe.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: b0bbdb66-604d-4985-9d54-54b426872436

📥 Commits

Reviewing files that changed from the base of the PR and between 707c0b7 and 3cdc177.

📒 Files selected for processing (1)

• tools/cli/cli.cpp