cosmopolitan/third_party/nsync/wait_s.internal.h
Justine Tunney 0a24b4fc3c
Clean up more code
The *NSYNC linked list API is good enough that it deserves to be part of
the C libray, so this change writes an improved version of it which uses
that offsetof() trick from the Linux Kernel. We vendor all of the *NSYNC
tests in third_party which helped confirm the needed refactoring is safe

This change also deletes more old code that didn't pan out. My goal here
is to work towards a vision where the Cosmopolitan core libraries become
less experimental and more focused on curation. This better reflects the
current level of quality we've managed to achieve.
2023-07-06 08:03:24 -07:00

26 lines
1.1 KiB
C

#ifndef COSMOPOLITAN_LIBC_THREAD_WAIT_INTERNAL_H_
#define COSMOPOLITAN_LIBC_THREAD_WAIT_INTERNAL_H_
#include "libc/intrin/dll.h"
#include "third_party/nsync/atomic.h"
#if !(__ASSEMBLER__ + __LINKER__ + 0)
COSMOPOLITAN_C_START_
/* Implementations of "struct nsync_waitable_s" must provide functions
in struct nsync_waitable_funcs_s (see public/nsync_wait.h). When
nsync_wait_n() waits on a client's object, those functions are called
with v pointing to the client's object and nw pointing to a struct
nsync_waiter_s. */
struct nsync_waiter_s {
uint32_t tag; /* used for debugging */
uint32_t flags; /* see below */
struct Dll q; /* used to link children of parent */
nsync_atomic_uint32_ waiting; /* non-zero <=> the waiter is waiting */
struct nsync_semaphore_s_ *sem; /* *sem will be Ved when waiter is woken */
};
/* set if waiter is embedded in Mu/CV's internal structures */
#define NSYNC_WAITER_FLAG_MUCV 0x1
COSMOPOLITAN_C_END_
#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
#endif /* COSMOPOLITAN_LIBC_THREAD_WAIT_INTERNAL_H_ */