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Diffstat (limited to '')
-rw-r--r-- | libusb-1.0/libusb/os/threads_windows.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/libusb-1.0/libusb/os/threads_windows.c b/libusb-1.0/libusb/os/threads_windows.c new file mode 100644 index 0000000..fe84ec0 --- /dev/null +++ b/libusb-1.0/libusb/os/threads_windows.c @@ -0,0 +1,221 @@ +/* + * libusb synchronization on Microsoft Windows + * + * Copyright (C) 2010 Michael Plante <michael.plante@gmail.com> + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <config.h> +#include <objbase.h> +#include <errno.h> +#include <stdarg.h> + +#include "libusbi.h" + +// Workaround for MinGW-w64 multilib bug +#if defined(_MSC_VER) || defined(_WIN64) +#define INIT_INTERLOCKEDEXCHANGE +#define pInterlockedExchange InterlockedExchange +#else +static LONG (WINAPI *pInterlockedExchange)(LONG volatile *, LONG) = NULL; +#define INIT_INTERLOCKEDEXCHANGE if (pInterlockedExchange == NULL) { \ + pInterlockedExchange = (LONG (WINAPI *)(LONG volatile *, LONG)) \ + GetProcAddress(GetModuleHandle("KERNEL32"), "InterlockedExchange"); \ + if (pInterlockedExchange == NULL) return ((errno=ENOENT)); \ + } +#endif + +int usbi_mutex_init(usbi_mutex_t *mutex, + const usbi_mutexattr_t *attr) { + if(! mutex) return ((errno=EINVAL)); + *mutex = CreateMutex(NULL, FALSE, NULL); + if(!*mutex) return ((errno=ENOMEM)); + return 0; +} +int usbi_mutex_destroy(usbi_mutex_t *mutex) { + // It is not clear if CloseHandle failure is due to failure to unlock. + // If so, this should be errno=EBUSY. + if(!mutex || !CloseHandle(*mutex)) return ((errno=EINVAL)); + *mutex = NULL; + return 0; +} +int usbi_mutex_trylock(usbi_mutex_t *mutex) { + DWORD result; + if(!mutex) return ((errno=EINVAL)); + result = WaitForSingleObject(*mutex, 0); + if(result == WAIT_OBJECT_0 || result == WAIT_ABANDONED) + return 0; // acquired (ToDo: check that abandoned is ok) + if(result == WAIT_TIMEOUT) + return ((errno=EBUSY)); + return ((errno=EINVAL)); // don't know how this would happen + // so don't know proper errno +} +int usbi_mutex_lock(usbi_mutex_t *mutex) { + DWORD result; + if(!mutex) return ((errno=EINVAL)); + result = WaitForSingleObject(*mutex, INFINITE); + if(result == WAIT_OBJECT_0 || result == WAIT_ABANDONED) + return 0; // acquired (ToDo: check that abandoned is ok) + return ((errno=EINVAL)); // don't know how this would happen + // so don't know proper errno +} +int usbi_mutex_unlock(usbi_mutex_t *mutex) { + if(!mutex) return ((errno=EINVAL)); + if(!ReleaseMutex(*mutex)) return ((errno=EPERM )); + return 0; +} + +int usbi_mutex_static_lock(usbi_mutex_static_t *mutex) { + if(!mutex) return ((errno=EINVAL)); + INIT_INTERLOCKEDEXCHANGE; + while (pInterlockedExchange((LONG *)mutex, 1) == 1) { + SleepEx(0, TRUE); + } + return 0; +} +int usbi_mutex_static_unlock(usbi_mutex_static_t *mutex) { + if(!mutex) return ((errno=EINVAL)); + *mutex = 0; + return 0; +} + + + +int usbi_cond_init(usbi_cond_t *cond, + const usbi_condattr_t *attr) { + if(!cond) return ((errno=EINVAL)); + list_init(&cond->waiters ); + list_init(&cond->not_waiting); + return 0; +} +int usbi_cond_destroy(usbi_cond_t *cond) { + // This assumes no one is using this anymore. The check MAY NOT BE safe. + struct usbi_cond_perthread *pos, *prev_pos = NULL; + if(!cond) return ((errno=EINVAL)); + if(!list_empty(&cond->waiters)) return ((errno=EBUSY )); // (!see above!) + list_for_each_entry(pos, &cond->not_waiting, list, struct usbi_cond_perthread) { + free(prev_pos); + list_del(&pos->list); + prev_pos = pos; + } + free(prev_pos); + prev_pos = pos = NULL; + + return 0; +} + +int usbi_cond_broadcast(usbi_cond_t *cond) { + // Assumes mutex is locked; this is not in keeping with POSIX spec, but + // libusb does this anyway, so we simplify by not adding more sync + // primitives to the CV definition! + int fail = 0; + struct usbi_cond_perthread *pos; + if(!cond) return ((errno=EINVAL)); + list_for_each_entry(pos, &cond->waiters, list, struct usbi_cond_perthread) { + if(!SetEvent(pos->event)) + fail = 1; + } + // The wait function will remove its respective item from the list. + return fail ? ((errno=EINVAL)) : 0; +} +int usbi_cond_signal(usbi_cond_t *cond) { + // Assumes mutex is locked; this is not in keeping with POSIX spec, but + // libusb does this anyway, so we simplify by not adding more sync + // primitives to the CV definition! + struct usbi_cond_perthread *pos; + if(!cond) return ((errno=EINVAL)); + if(list_empty(&cond->waiters)) return 0; // no one to wakeup. + pos = list_entry(&cond->waiters.next, struct usbi_cond_perthread, list); + // The wait function will remove its respective item from the list. + return SetEvent(pos->event) ? 0 : ((errno=EINVAL)); +} +static int __inline usbi_cond_intwait(usbi_cond_t *cond, + usbi_mutex_t *mutex, + DWORD timeout_ms) { + struct usbi_cond_perthread *pos; + int found = 0, r; + DWORD r2,tid = GetCurrentThreadId(); + if(!cond || !mutex) return ((errno=EINVAL)); + list_for_each_entry(pos, &cond->not_waiting, list, struct usbi_cond_perthread) { + if(tid == pos->tid) { + found = 1; + break; + } + } + if(!found) { + pos = malloc(sizeof(struct usbi_cond_perthread)); + if(!pos) return ((errno=ENOMEM)); // This errno is not POSIX-allowed. + pos->tid = tid; + pos->event = CreateEvent(NULL, FALSE, FALSE, NULL); // auto-reset. + if(!pos->event) { + free(pos); + return ((errno=ENOMEM)); + } + list_add(&pos->list, &cond->not_waiting); + } + + list_del(&pos->list); // remove from not_waiting list. + list_add(&pos->list, &cond->waiters); + + r = usbi_mutex_unlock(mutex); + if(r) return r; + r2 = WaitForSingleObject(pos->event, timeout_ms); + r = usbi_mutex_lock(mutex); + if(r) return r; + + list_del(&pos->list); + list_add(&pos->list, &cond->not_waiting); + + if(r2 == WAIT_TIMEOUT) return ((errno=ETIMEDOUT)); + + return 0; +} +// N.B.: usbi_cond_*wait() can also return ENOMEM, even though pthread_cond_*wait cannot! +int usbi_cond_wait(usbi_cond_t *cond, usbi_mutex_t *mutex) { + return usbi_cond_intwait(cond, mutex, INFINITE); +} +int usbi_cond_timedwait(usbi_cond_t *cond, + usbi_mutex_t *mutex, + const struct timespec *abstime) { + FILETIME filetime; + ULARGE_INTEGER rtime; + struct timeval targ_time, cur_time, delta_time; + struct timespec cur_time_ns; + DWORD millis; + extern const uint64_t epoch_time; + + GetSystemTimeAsFileTime(&filetime); + rtime.LowPart = filetime.dwLowDateTime; + rtime.HighPart = filetime.dwHighDateTime; + rtime.QuadPart -= epoch_time; + cur_time_ns.tv_sec = (long)(rtime.QuadPart / 10000000); + cur_time_ns.tv_nsec = (long)((rtime.QuadPart % 10000000)*100); + TIMESPEC_TO_TIMEVAL(&cur_time, &cur_time_ns); + + TIMESPEC_TO_TIMEVAL(&targ_time, abstime); + timersub(&targ_time, &cur_time, &delta_time); + if(delta_time.tv_sec < 0) // abstime already passed? + millis = 0; + else { + millis = delta_time.tv_usec/1000; + millis += delta_time.tv_sec *1000; + if (delta_time.tv_usec % 1000) // round up to next millisecond + millis++; + } + + return usbi_cond_intwait(cond, mutex, millis); +} + |