microassert

microassert is a small assert and panic library for C and C++ consumers. It has no third-party dependencies and formats messages with the standard C library vsnprintf.

Features

• explicit, status-returning initialization
• caller-owned hook storage and retained history storage
• WARN, ERROR, FATAL, and HALT severities
• copied history entries with bounded text buffers
• deterministic nested-panic handling and terminal callbacks
• C99 minimum, C11-compatible source
• C and C++ header compatibility

Quick Start

#include"massert.h"staticuint32_tclock_ms(void)
{
return1234u;
}
staticvoidreset_cb(void*ctx)
{
(void)ctx;
}
staticvoidhalt_cb(void*ctx)
{
(void)ctx;
}
intmain(void)
{
massert_hook_slot_thooks[2];
massert_history_entry_thistory[4];
massert_tma;
massert_config_tconfig= {
hooks,
2u,
history,
4u,
clock_ms,
reset_cb,
NULL,
halt_cb,
NULL
};
if (massert_init(&ma, &config) !=MASSERT_STATUS_OK) {
return1;
}
MASSERT_WARN(1==1, "not reached");
MASSERT_MSG(2==3, "mismatch: %d", 3);
MPANIC("fatal condition");
}

Build

Direct Makefile workflow:

mingw32-make test

CMake workflow:

cmake -S . -B build -G Ninja -DCMAKE_C_COMPILER=gcc -DCMAKE_CXX_COMPILER=g++
cmake --build build
ctest --test-dir build --output-on-failure
cmake --install build --prefix /tmp/microassert-install

Public API

• massert_init() validates caller storage and copies callbacks by value.
• massert_set_reset() and massert_set_halt() reject mutation while a panic is active.
• massert_fire() routes WARN and ERROR back to the caller, while FATAL and HALT are terminal.
• massert_panic_fatal() calls reset, then halt if reset returns, then spins.
• massert_panic_halt() calls halt, then spins if halt returns.
• massert_history_at() returns retained copied history, valid until overwritten or reinit.

Notes

• Hooks are best-effort and do not guarantee logging, persistence, or flushing.
• The global singleton is deterministic, but the library is not thread-safe.
• FATAL and HALT do not unwind C frames or run C++ destructors.
• Hardware fault handling, signals, and power-loss recovery are outside the library contract.

Documentation

• API reference
• Cookbook
• Design notes
• Porting guide
• Troubleshooting
• Verification notes
• Contributing
• Security policy
• Changelog

License

MIT, see LICENSE.