cosmopolitan/third_party/tz/lock.h

#ifndef COSMOPOLITAN_THIRD_PARTY_TZ_LOCK_H_
#define COSMOPOLITAN_THIRD_PARTY_TZ_LOCK_H_
#include "libc/thread/thread.h"
COSMOPOLITAN_C_START_

extern pthread_mutex_t __localtime_lock_obj;

void __localtime_lock(void);
void __localtime_unlock(void);

COSMOPOLITAN_C_END_
#endif /* COSMOPOLITAN_THIRD_PARTY_TZ_LOCK_H_ */
Eliminate cyclic locks in runtime This change introduces a new deadlock detector for Cosmo's POSIX threads implementation. Error check mutexes will now track a DAG of nested locks and report EDEADLK when a deadlock is theoretically possible. These will occur rarely, but it's important for production hardening your code. You don't even need to change your mutexes to use the POSIX error check mode because `cosmocc -mdbg` will enable error checking on mutexes by default globally. When cycles are found, an error message showing your demangled symbols describing the strongly connected component are printed and then the SIGTRAP is raised, which means you'll also get a backtrace if you're using ShowCrashReports() too. This new error checker is so low-level and so pure that it's able to verify the relationships of every libc runtime lock, including those locks upon which the mutex implementation depends. 2024-12-16 20:51:27 -08:00			`#ifndef COSMOPOLITAN_THIRD_PARTY_TZ_LOCK_H_`
			`#define COSMOPOLITAN_THIRD_PARTY_TZ_LOCK_H_`
			`#include "libc/thread/thread.h"`
			`COSMOPOLITAN_C_START_`

			`extern pthread_mutex_t __localtime_lock_obj;`

			`void __localtime_lock(void);`
			`void __localtime_unlock(void);`

			`COSMOPOLITAN_C_END_`
			`#endif /* COSMOPOLITAN_THIRD_PARTY_TZ_LOCK_H_ */`