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Diffstat (limited to 'lib/mlibc/options/posix/generic/semaphore-stubs.cpp')
-rw-r--r--lib/mlibc/options/posix/generic/semaphore-stubs.cpp114
1 files changed, 0 insertions, 114 deletions
diff --git a/lib/mlibc/options/posix/generic/semaphore-stubs.cpp b/lib/mlibc/options/posix/generic/semaphore-stubs.cpp
deleted file mode 100644
index d41eccb..0000000
--- a/lib/mlibc/options/posix/generic/semaphore-stubs.cpp
+++ /dev/null
@@ -1,114 +0,0 @@
-#include <semaphore.h>
-#include <errno.h>
-
-#include <bits/ensure.h>
-#include <mlibc/debug.hpp>
-#include <mlibc/ansi-sysdeps.hpp>
-#include <mlibc/posix-sysdeps.hpp>
-
-static constexpr unsigned int semaphoreHasWaiters = static_cast<uint32_t>(1 << 31);
-static constexpr unsigned int semaphoreCountMask = static_cast<uint32_t>(1 << 31) - 1;
-
-int sem_init(sem_t *sem, int pshared, unsigned int initial_count) {
- if (pshared) {
- mlibc::infoLogger() << "mlibc: shared semaphores are unsuppored" << frg::endlog;
- errno = ENOSYS;
- return -1;
- }
-
- if (initial_count > SEM_VALUE_MAX) {
- errno = EINVAL;
- return -1;
- }
-
- sem->__mlibc_count = initial_count;
-
- return 0;
-}
-
-int sem_destroy(sem_t *) {
- return 0;
-}
-
-int sem_wait(sem_t *sem) {
- unsigned int state = 0;
-
- while (1) {
- if (!(state & semaphoreCountMask)) {
- if (__atomic_compare_exchange_n(&sem->__mlibc_count, &state, semaphoreHasWaiters,
- false, __ATOMIC_ACQUIRE, __ATOMIC_ACQUIRE)) {
- int e = mlibc::sys_futex_wait((int *)&sem->__mlibc_count, state, nullptr);
- if (e == 0 || e == EAGAIN) {
- continue;
- } else if (e == EINTR) {
- errno = EINTR;
- return -1;
- } else {
- mlibc::panicLogger() << "sys_futex_wait() failed with error code " << e << frg::endlog;
- }
- }
- } else {
- unsigned int desired = (state - 1);
- if (__atomic_compare_exchange_n(&sem->__mlibc_count, &state, desired, false,
- __ATOMIC_RELAXED, __ATOMIC_RELAXED))
- return 0;
- }
- }
-}
-
-int sem_timedwait(sem_t *sem, const struct timespec *) {
- mlibc::infoLogger() << "\e[31mmlibc: sem_timedwait is implemented as sem_wait\e[0m" << frg::endlog;
- return sem_wait(sem);
-}
-
-int sem_post(sem_t *sem) {
- auto old_count = __atomic_load_n(&sem->__mlibc_count, __ATOMIC_RELAXED) & semaphoreCountMask;
-
- if (old_count + 1 > SEM_VALUE_MAX) {
- errno = EOVERFLOW;
- return -1;
- }
-
- auto state = __atomic_exchange_n(&sem->__mlibc_count, old_count + 1, __ATOMIC_RELEASE);
-
- if (state & semaphoreHasWaiters)
- if (int e = mlibc::sys_futex_wake((int *)&sem->__mlibc_count); e)
- __ensure(!"sys_futex_wake() failed");
-
- return 0;
-}
-
-sem_t *sem_open(const char *, int, ...) {
- __ensure(!"Not implemented");
- __builtin_unreachable();
-}
-
-int sem_close(sem_t *) {
- __ensure(!"Not implemented");
- __builtin_unreachable();
-}
-
-int sem_getvalue(sem_t *, int *) {
- __ensure(!"Not implemented");
- __builtin_unreachable();
-}
-
-int sem_unlink(const char *) {
- __ensure(!"Not implemented");
- __builtin_unreachable();
-}
-
-int sem_trywait(sem_t *sem) {
- while (true) {
- auto state = __atomic_load_n(&sem->__mlibc_count, __ATOMIC_ACQUIRE);
-
- if (state & semaphoreHasWaiters) {
- return EAGAIN;
- }
-
- auto desired = state - 1;
- if (__atomic_compare_exchange_n(&sem->__mlibc_count, &state, desired, false, __ATOMIC_RELEASE, __ATOMIC_RELAXED)) {
- return 0;
- }
- }
-}