Function calltrace_cleanup

Source

#[unsafe(no_mangle)]
pub extern "C" fn calltrace_cleanup()

Expand description

Cleanup the CallTrace library and write final output

This function performs comprehensive cleanup of the CallTrace library:

Flushes all pending thread-local performance counters
Generates and writes the final JSON trace output
Restores original signal handlers
Releases all allocated resources

§Safety

This function is automatically called when the library is unloaded via dtor attributes. It handles cleanup gracefully even during abnormal program termination.

§Thread Safety

This function is designed to be signal-safe and can be called during:

Normal program exit
Library unloading
Signal handler execution
Thread destruction

§Output Generation

If CALLTRACE_OUTPUT was specified, this function will:

Collect all call trees from all threads
Generate metadata (timing, counters, environment)
Serialize to structured JSON format
Write atomically to the specified file

§Error Handling

Cleanup continues even if individual steps fail. Errors are logged to stderr but do not prevent other cleanup operations from completing.

§Examples

Usually called automatically, but can be invoked manually:

// In C code - force immediate cleanup and output
extern void calltrace_cleanup(void);
calltrace_cleanup();

§Performance Notes

Thread-local counter flushing: O(number of threads)
JSON generation: O(total function calls)
File I/O: O(output file size)
Signal handler restoration: O(number of signals)

calltrace_cleanup