diff options
Diffstat (limited to 'src/common/compat_winthreads.c')
-rw-r--r-- | src/common/compat_winthreads.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/src/common/compat_winthreads.c b/src/common/compat_winthreads.c new file mode 100644 index 0000000000..71b994c4e4 --- /dev/null +++ b/src/common/compat_winthreads.c @@ -0,0 +1,196 @@ +/* Copyright (c) 2003-2004, Roger Dingledine + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2015, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#include "compat.h" +#include <windows.h> +#include <process.h> +#include "util.h" +#include "container.h" +#include "torlog.h" +#include <process.h> + +/* This value is more or less total cargo-cult */ +#define SPIN_COUNT 2000 + +/** Minimalist interface to run a void function in the background. On + * Unix calls fork, on win32 calls beginthread. Returns -1 on failure. + * func should not return, but rather should call spawn_exit. + * + * NOTE: if <b>data</b> is used, it should not be allocated on the stack, + * since in a multithreaded environment, there is no way to be sure that + * the caller's stack will still be around when the called function is + * running. + */ +int +spawn_func(void (*func)(void *), void *data) +{ + int rv; + rv = (int)_beginthread(func, 0, data); + if (rv == (int)-1) + return -1; + return 0; +} + +/** End the current thread/process. + */ +void +spawn_exit(void) +{ + _endthread(); + //we should never get here. my compiler thinks that _endthread returns, this + //is an attempt to fool it. + tor_assert(0); + _exit(0); +} + +void +tor_mutex_init(tor_mutex_t *m) +{ + InitializeCriticalSection(&m->mutex); +} +void +tor_mutex_init_nonrecursive(tor_mutex_t *m) +{ + InitializeCriticalSection(&m->mutex); +} + +void +tor_mutex_uninit(tor_mutex_t *m) +{ + DeleteCriticalSection(&m->mutex); +} +void +tor_mutex_acquire(tor_mutex_t *m) +{ + tor_assert(m); + EnterCriticalSection(&m->mutex); +} +void +tor_mutex_release(tor_mutex_t *m) +{ + LeaveCriticalSection(&m->mutex); +} +unsigned long +tor_get_thread_id(void) +{ + return (unsigned long)GetCurrentThreadId(); +} + +int +tor_cond_init(tor_cond_t *cond) +{ + memset(cond, 0, sizeof(tor_cond_t)); + if (InitializeCriticalSectionAndSpinCount(&cond->lock, SPIN_COUNT)==0) { + return -1; + } + if ((cond->event = CreateEvent(NULL,TRUE,FALSE,NULL)) == NULL) { + DeleteCriticalSection(&cond->lock); + return -1; + } + cond->n_waiting = cond->n_to_wake = cond->generation = 0; + return 0; +} +void +tor_cond_uninit(tor_cond_t *cond) +{ + DeleteCriticalSection(&cond->lock); + CloseHandle(cond->event); +} + +static void +tor_cond_signal_impl(tor_cond_t *cond, int broadcast) +{ + EnterCriticalSection(&cond->lock); + if (broadcast) + cond->n_to_wake = cond->n_waiting; + else + ++cond->n_to_wake; + cond->generation++; + SetEvent(cond->event); + LeaveCriticalSection(&cond->lock); +} +void +tor_cond_signal_one(tor_cond_t *cond) +{ + tor_cond_signal_impl(cond, 0); +} +void +tor_cond_signal_all(tor_cond_t *cond) +{ + tor_cond_signal_impl(cond, 1); +} + +int +tor_cond_wait(tor_cond_t *cond, tor_mutex_t *lock_, const struct timeval *tv) +{ + CRITICAL_SECTION *lock = &lock_->mutex; + int generation_at_start; + int waiting = 1; + int result = -1; + DWORD ms = INFINITE, ms_orig = INFINITE, startTime, endTime; + if (tv) + ms_orig = ms = tv->tv_sec*1000 + (tv->tv_usec+999)/1000; + + EnterCriticalSection(&cond->lock); + ++cond->n_waiting; + generation_at_start = cond->generation; + LeaveCriticalSection(&cond->lock); + + LeaveCriticalSection(lock); + + startTime = GetTickCount(); + do { + DWORD res; + res = WaitForSingleObject(cond->event, ms); + EnterCriticalSection(&cond->lock); + if (cond->n_to_wake && + cond->generation != generation_at_start) { + --cond->n_to_wake; + --cond->n_waiting; + result = 0; + waiting = 0; + goto out; + } else if (res != WAIT_OBJECT_0) { + result = (res==WAIT_TIMEOUT) ? 1 : -1; + --cond->n_waiting; + waiting = 0; + goto out; + } else if (ms != INFINITE) { + endTime = GetTickCount(); + if (startTime + ms_orig <= endTime) { + result = 1; /* Timeout */ + --cond->n_waiting; + waiting = 0; + goto out; + } else { + ms = startTime + ms_orig - endTime; + } + } + /* If we make it here, we are still waiting. */ + if (cond->n_to_wake == 0) { + /* There is nobody else who should wake up; reset + * the event. */ + ResetEvent(cond->event); + } + out: + LeaveCriticalSection(&cond->lock); + } while (waiting); + + EnterCriticalSection(lock); + + EnterCriticalSection(&cond->lock); + if (!cond->n_waiting) + ResetEvent(cond->event); + LeaveCriticalSection(&cond->lock); + + return result; +} + +void +tor_threads_init(void) +{ + set_main_thread(); +} + |