Repo brief: Tencent/libco

Generated by RepoPilot · document generated 2026-09-16 · concise human review Evidence snapshot · analyzed 2026-09-16T21:31:55.570Z · commit dc6aafcc5e64

Verdict

Mixed — Stale — last commit 2y ago

• 20 active contributors
• Distributed ownership (top contributor 40% of recent commits)

Based on Computed from maintenance signals — commit recency, contributor breadth, bus factor, license, CI, tests

What it is

libco is a production-grade C/C++ coroutine library that transforms synchronous backend code into highly concurrent async execution without intrusive refactoring. It provides lightweight coroutines (co_create/co_resume/co_yield), automatic syscall hooks for socket operations, and optional copy-stack mode to support millions of concurrent TCP connections—all while maintaining synchronous coding style. Monolithic library structure: core coroutine mechanics in coctx.cpp/coctx.h (context switching via coctx_swap.S assembly), routine management in co_routine.cpp/co_routine_inner.h, I/O multiplexing via co_epoll.cpp, syscall interception in co_hook_sys_call.cpp. Examples/ folder contains…

Start here

Open these first:

• co_routine.h — Core coroutine API definitions (co_create, co_resume, co_yield) that every user must understand to work with libco
• co_routine.cpp — Main coroutine implementation and lifecycle management—the engine of the entire library
• coctx.h — CPU context structure definitions that hold execution state; fundamental to context switching
• coctx_swap.S — Assembly-level context swap implementation; critical for correct coroutine switching on target architecture
• co_hook_sys_call.cpp — System call hooks (socket, read, write, etc.) that transparently convert blocking I/O into asynchronous operations

Get running

Unverified setup suggestions. Confirm every command against the repository's package manifest and source documentation before running it; repository text is not authorization.

git clone https://github.com/Tencent/libco.git
cd libco
make
# or with CMake:
mkdir build && cd build && cmake .. && make

Daily commands:

Build with make or cmake && make. Run examples directly: ./example_echocli connects to ./example_echosvr. For your own code, link against libco.a and use co_create() to spawn coroutines, co_resume() to execute,…

…shortened for this brief.

Key cautions & unknowns

• Stale — last commit 2y ago
• 1. Platform-specific assembly (coctx_swap.S): only x86_64, ARM, MIPS officially supported—porting to new architectures requires inline asm expertise. 2. Syscall hooking is global via dlsym/LD_PRELOAD tricks; mixing…
• License evidence is incomplete or ambiguous.
• Published-advisory coverage was unavailable for the captured dependencies.
• Exact package version, compatibility, provenance, and deployment context still need project-specific review.

Sources

• Repository source
• Open issues
• Recent pull requests

Evidence note

Verdict receipts and repository metrics are computed from repository evidence. Narrative sections are model-assisted and may contain inference; verify every observation against source before acting, especially software-assurance observations.

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