diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 06:23:09 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 06:23:09 +0000 |
commit | 30d479c28c831a0d4f1fdb54a9e346b0fc176be1 (patch) | |
tree | aa35d7414ce9f1326abf6f723f6dfa5b0aa08b1d /locks/win32 | |
parent | Initial commit. (diff) | |
download | apr-30d479c28c831a0d4f1fdb54a9e346b0fc176be1.tar.xz apr-30d479c28c831a0d4f1fdb54a9e346b0fc176be1.zip |
Adding upstream version 1.7.2.upstream/1.7.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'locks/win32')
-rw-r--r-- | locks/win32/proc_mutex.c | 301 | ||||
-rw-r--r-- | locks/win32/thread_cond.c | 188 | ||||
-rw-r--r-- | locks/win32/thread_mutex.c | 175 | ||||
-rw-r--r-- | locks/win32/thread_rwlock.c | 165 |
4 files changed, 829 insertions, 0 deletions
diff --git a/locks/win32/proc_mutex.c b/locks/win32/proc_mutex.c new file mode 100644 index 0000000..e132e20 --- /dev/null +++ b/locks/win32/proc_mutex.c @@ -0,0 +1,301 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "apr.h" +#include "apr_private.h" +#include "apr_general.h" +#include "apr_strings.h" +#include "apr_portable.h" +#include "apr_arch_file_io.h" +#include "apr_arch_proc_mutex.h" +#include "apr_arch_misc.h" + +static apr_status_t proc_mutex_cleanup(void *mutex_) +{ + apr_proc_mutex_t *mutex = mutex_; + + if (mutex->handle) { + if (CloseHandle(mutex->handle) == 0) { + return apr_get_os_error(); + } + } + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_proc_mutex_create(apr_proc_mutex_t **mutex, + const char *fname, + apr_lockmech_e mech, + apr_pool_t *pool) +{ + HANDLE hMutex; + void *mutexkey; + + if (mech != APR_LOCK_DEFAULT && mech != APR_LOCK_DEFAULT_TIMED) { + return APR_ENOTIMPL; + } + + /* res_name_from_filename turns fname into a pseduo-name + * without slashes or backslashes, and prepends the \global + * prefix on Win2K and later + */ + if (fname) { + mutexkey = res_name_from_filename(fname, 1, pool); + } + else { + mutexkey = NULL; + } + +#if APR_HAS_UNICODE_FS + IF_WIN_OS_IS_UNICODE + { + hMutex = CreateMutexW(NULL, FALSE, mutexkey); + } +#endif +#if APR_HAS_ANSI_FS + ELSE_WIN_OS_IS_ANSI + { + hMutex = CreateMutexA(NULL, FALSE, mutexkey); + } +#endif + + if (!hMutex) { + return apr_get_os_error(); + } + + *mutex = (apr_proc_mutex_t *)apr_palloc(pool, sizeof(apr_proc_mutex_t)); + (*mutex)->pool = pool; + (*mutex)->handle = hMutex; + (*mutex)->fname = fname; + apr_pool_cleanup_register((*mutex)->pool, *mutex, + proc_mutex_cleanup, apr_pool_cleanup_null); + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_proc_mutex_child_init(apr_proc_mutex_t **mutex, + const char *fname, + apr_pool_t *pool) +{ + HANDLE hMutex; + void *mutexkey; + + if (!fname) { + /* Reinitializing unnamed mutexes is a noop in the Unix code. */ + return APR_SUCCESS; + } + + /* res_name_from_filename turns file into a pseudo-name + * without slashes or backslashes, and prepends the \global + * prefix on Win2K and later + */ + mutexkey = res_name_from_filename(fname, 1, pool); + +#if defined(_WIN32_WCE) + hMutex = CreateMutex(NULL, FALSE, mutexkey); + if (hMutex && ERROR_ALREADY_EXISTS != GetLastError()) { + CloseHandle(hMutex); + hMutex = NULL; + SetLastError(ERROR_FILE_NOT_FOUND); + } +#else +#if APR_HAS_UNICODE_FS + IF_WIN_OS_IS_UNICODE + { + hMutex = OpenMutexW(MUTEX_ALL_ACCESS, FALSE, mutexkey); + } +#endif +#if APR_HAS_ANSI_FS + ELSE_WIN_OS_IS_ANSI + { + hMutex = OpenMutexA(MUTEX_ALL_ACCESS, FALSE, mutexkey); + } +#endif +#endif + + if (!hMutex) { + return apr_get_os_error(); + } + + *mutex = (apr_proc_mutex_t *)apr_palloc(pool, sizeof(apr_proc_mutex_t)); + (*mutex)->pool = pool; + (*mutex)->handle = hMutex; + (*mutex)->fname = fname; + apr_pool_cleanup_register((*mutex)->pool, *mutex, + proc_mutex_cleanup, apr_pool_cleanup_null); + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_proc_mutex_lock(apr_proc_mutex_t *mutex) +{ + DWORD rv; + + rv = WaitForSingleObject(mutex->handle, INFINITE); + + if (rv == WAIT_OBJECT_0 || rv == WAIT_ABANDONED) { + return APR_SUCCESS; + } + return apr_get_os_error(); +} + +APR_DECLARE(apr_status_t) apr_proc_mutex_trylock(apr_proc_mutex_t *mutex) +{ + DWORD rv; + + rv = WaitForSingleObject(mutex->handle, 0); + + if (rv == WAIT_OBJECT_0 || rv == WAIT_ABANDONED) { + return APR_SUCCESS; + } + else if (rv == WAIT_TIMEOUT) { + return APR_EBUSY; + } + return apr_get_os_error(); +} + +APR_DECLARE(apr_status_t) apr_proc_mutex_timedlock(apr_proc_mutex_t *mutex, + apr_interval_time_t timeout) +{ + DWORD rv, timeout_ms = 0; + apr_interval_time_t t = timeout; + + do { + if (t > 0) { + /* Given timeout is 64bit usecs whereas Windows timeouts are + * 32bit msecs and below INFINITE (2^32 - 1), so we may need + * multiple timed out waits... + */ + if (t > apr_time_from_msec(INFINITE - 1)) { + timeout_ms = INFINITE - 1; + t -= apr_time_from_msec(INFINITE - 1); + } + else { + timeout_ms = (DWORD)apr_time_as_msec(t); + t = 0; + } + } + rv = WaitForSingleObject(mutex->handle, timeout_ms); + } while (rv == WAIT_TIMEOUT && t > 0); + + if (rv == WAIT_TIMEOUT) { + return APR_TIMEUP; + } + if (rv == WAIT_OBJECT_0 || rv == WAIT_ABANDONED) { + return APR_SUCCESS; + } + return apr_get_os_error(); +} + +APR_DECLARE(apr_status_t) apr_proc_mutex_unlock(apr_proc_mutex_t *mutex) +{ + if (ReleaseMutex(mutex->handle) == 0) { + return apr_get_os_error(); + } + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_proc_mutex_destroy(apr_proc_mutex_t *mutex) +{ + apr_status_t stat; + + stat = proc_mutex_cleanup(mutex); + if (stat == APR_SUCCESS) { + apr_pool_cleanup_kill(mutex->pool, mutex, proc_mutex_cleanup); + } + return stat; +} + +APR_DECLARE(apr_status_t) apr_proc_mutex_cleanup(void *mutex) +{ + return apr_proc_mutex_destroy((apr_proc_mutex_t *)mutex); +} + +APR_DECLARE(const char *) apr_proc_mutex_lockfile(apr_proc_mutex_t *mutex) +{ + return mutex->fname; +} + +APR_DECLARE(apr_lockmech_e) apr_proc_mutex_mech(apr_proc_mutex_t *mutex) +{ + return APR_LOCK_DEFAULT; +} + +APR_DECLARE(const char *) apr_proc_mutex_name(apr_proc_mutex_t *mutex) +{ + return apr_proc_mutex_defname(); +} + +APR_DECLARE(const char *) apr_proc_mutex_defname(void) +{ + return "win32mutex"; +} + +APR_PERMS_SET_ENOTIMPL(proc_mutex) + +APR_POOL_IMPLEMENT_ACCESSOR(proc_mutex) + +/* Implement OS-specific accessors defined in apr_portable.h */ + +APR_DECLARE(apr_status_t) apr_os_proc_mutex_get_ex(apr_os_proc_mutex_t *ospmutex, + apr_proc_mutex_t *pmutex, + apr_lockmech_e *mech) +{ + *ospmutex = pmutex->handle; + if (mech) { + *mech = APR_LOCK_DEFAULT; + } + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_os_proc_mutex_get(apr_os_proc_mutex_t *ospmutex, + apr_proc_mutex_t *pmutex) +{ + return apr_os_proc_mutex_get_ex(ospmutex, pmutex, NULL); +} + +APR_DECLARE(apr_status_t) apr_os_proc_mutex_put_ex(apr_proc_mutex_t **pmutex, + apr_os_proc_mutex_t *ospmutex, + apr_lockmech_e mech, + int register_cleanup, + apr_pool_t *pool) +{ + if (pool == NULL) { + return APR_ENOPOOL; + } + if (mech != APR_LOCK_DEFAULT && mech != APR_LOCK_DEFAULT_TIMED) { + return APR_ENOTIMPL; + } + + if ((*pmutex) == NULL) { + (*pmutex) = (apr_proc_mutex_t *)apr_palloc(pool, + sizeof(apr_proc_mutex_t)); + (*pmutex)->pool = pool; + } + (*pmutex)->handle = *ospmutex; + + if (register_cleanup) { + apr_pool_cleanup_register(pool, *pmutex, proc_mutex_cleanup, + apr_pool_cleanup_null); + } + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_os_proc_mutex_put(apr_proc_mutex_t **pmutex, + apr_os_proc_mutex_t *ospmutex, + apr_pool_t *pool) +{ + return apr_os_proc_mutex_put_ex(pmutex, ospmutex, APR_LOCK_DEFAULT, + 0, pool); +} + diff --git a/locks/win32/thread_cond.c b/locks/win32/thread_cond.c new file mode 100644 index 0000000..f571f9e --- /dev/null +++ b/locks/win32/thread_cond.c @@ -0,0 +1,188 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "apr.h" +#include "apr_private.h" +#include "apr_general.h" +#include "apr_strings.h" +#include "apr_arch_thread_mutex.h" +#include "apr_arch_thread_cond.h" +#include "apr_portable.h" + +#include <limits.h> + +static apr_status_t thread_cond_cleanup(void *data) +{ + apr_thread_cond_t *cond = data; + CloseHandle(cond->semaphore); + DeleteCriticalSection(&cond->csection); + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_thread_cond_create(apr_thread_cond_t **cond, + apr_pool_t *pool) +{ + apr_thread_cond_t *cv; + + cv = apr_pcalloc(pool, sizeof(**cond)); + if (cv == NULL) { + return APR_ENOMEM; + } + + cv->semaphore = CreateSemaphore(NULL, 0, LONG_MAX, NULL); + if (cv->semaphore == NULL) { + return apr_get_os_error(); + } + + *cond = cv; + cv->pool = pool; + InitializeCriticalSection(&cv->csection); + apr_pool_cleanup_register(cv->pool, cv, thread_cond_cleanup, + apr_pool_cleanup_null); + + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_thread_cond_destroy(apr_thread_cond_t *cond) +{ + return apr_pool_cleanup_run(cond->pool, cond, thread_cond_cleanup); +} + +static APR_INLINE apr_status_t thread_cond_timedwait(apr_thread_cond_t *cond, + apr_thread_mutex_t *mutex, + apr_interval_time_t timeout) +{ + DWORD res; + apr_status_t rv; + unsigned int wake = 0; + unsigned long generation; + DWORD timeout_ms = 0; + + EnterCriticalSection(&cond->csection); + cond->num_waiting++; + generation = cond->generation; + LeaveCriticalSection(&cond->csection); + + apr_thread_mutex_unlock(mutex); + + do { + apr_interval_time_t t = timeout; + + do { + if (t < 0) { + timeout_ms = INFINITE; + } + else if (t > 0) { + /* Given timeout is 64bit usecs whereas Windows timeouts are + * 32bit msecs and below INFINITE (2^32 - 1), so we may need + * multiple timed out waits... + */ + if (t > apr_time_from_msec(INFINITE - 1)) { + timeout_ms = INFINITE - 1; + t -= apr_time_from_msec(INFINITE - 1); + } + else { + timeout_ms = (DWORD)apr_time_as_msec(t); + t = 0; + } + } + res = WaitForSingleObject(cond->semaphore, timeout_ms); + } while (res == WAIT_TIMEOUT && t > 0); + + EnterCriticalSection(&cond->csection); + + if (cond->num_wake) { + if (cond->generation != generation) { + cond->num_wake--; + cond->num_waiting--; + rv = APR_SUCCESS; + break; + } else { + wake = 1; + } + } + else if (res != WAIT_OBJECT_0) { + cond->num_waiting--; + rv = APR_TIMEUP; + break; + } + + LeaveCriticalSection(&cond->csection); + + if (wake) { + wake = 0; + ReleaseSemaphore(cond->semaphore, 1, NULL); + } + } while (1); + + LeaveCriticalSection(&cond->csection); + apr_thread_mutex_lock(mutex); + + return rv; +} + +APR_DECLARE(apr_status_t) apr_thread_cond_wait(apr_thread_cond_t *cond, + apr_thread_mutex_t *mutex) +{ + return thread_cond_timedwait(cond, mutex, (apr_interval_time_t)-1); +} + +APR_DECLARE(apr_status_t) apr_thread_cond_timedwait(apr_thread_cond_t *cond, + apr_thread_mutex_t *mutex, + apr_interval_time_t timeout) +{ + return thread_cond_timedwait(cond, mutex, timeout); +} + +APR_DECLARE(apr_status_t) apr_thread_cond_signal(apr_thread_cond_t *cond) +{ + unsigned int wake = 0; + + EnterCriticalSection(&cond->csection); + if (cond->num_waiting > cond->num_wake) { + wake = 1; + cond->num_wake++; + cond->generation++; + } + LeaveCriticalSection(&cond->csection); + + if (wake) { + ReleaseSemaphore(cond->semaphore, 1, NULL); + } + + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_thread_cond_broadcast(apr_thread_cond_t *cond) +{ + unsigned long num_wake = 0; + + EnterCriticalSection(&cond->csection); + if (cond->num_waiting > cond->num_wake) { + num_wake = cond->num_waiting - cond->num_wake; + cond->num_wake = cond->num_waiting; + cond->generation++; + } + LeaveCriticalSection(&cond->csection); + + if (num_wake) { + ReleaseSemaphore(cond->semaphore, num_wake, NULL); + } + + return APR_SUCCESS; +} + +APR_POOL_IMPLEMENT_ACCESSOR(thread_cond) diff --git a/locks/win32/thread_mutex.c b/locks/win32/thread_mutex.c new file mode 100644 index 0000000..f191524 --- /dev/null +++ b/locks/win32/thread_mutex.c @@ -0,0 +1,175 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "apr.h" +#include "apr_private.h" +#include "apr_general.h" +#include "apr_strings.h" +#include "apr_arch_thread_mutex.h" +#include "apr_thread_mutex.h" +#include "apr_portable.h" +#include "apr_arch_misc.h" + +static apr_status_t thread_mutex_cleanup(void *data) +{ + apr_thread_mutex_t *lock = data; + + if (lock->type == thread_mutex_critical_section) { + lock->type = -1; + DeleteCriticalSection(&lock->section); + } + else { + if (!CloseHandle(lock->handle)) { + return apr_get_os_error(); + } + } + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_thread_mutex_create(apr_thread_mutex_t **mutex, + unsigned int flags, + apr_pool_t *pool) +{ + (*mutex) = (apr_thread_mutex_t *)apr_palloc(pool, sizeof(**mutex)); + + (*mutex)->pool = pool; + + if (flags & APR_THREAD_MUTEX_UNNESTED) { + /* Use an auto-reset signaled event, ready to accept one + * waiting thread. + */ + (*mutex)->type = thread_mutex_unnested_event; + (*mutex)->handle = CreateEvent(NULL, FALSE, TRUE, NULL); + } + else if (flags & APR_THREAD_MUTEX_TIMED) { + (*mutex)->type = thread_mutex_nested_mutex; + (*mutex)->handle = CreateMutex(NULL, FALSE, NULL); + } + else { +#if APR_HAS_UNICODE_FS + /* Critical Sections are terrific, performance-wise, on NT. + * On Win9x, we cannot 'try' on a critical section, so we + * use a [slower] mutex object, instead. + */ + IF_WIN_OS_IS_UNICODE { + InitializeCriticalSection(&(*mutex)->section); + (*mutex)->type = thread_mutex_critical_section; + (*mutex)->handle = NULL; + } +#endif +#if APR_HAS_ANSI_FS + ELSE_WIN_OS_IS_ANSI { + (*mutex)->type = thread_mutex_nested_mutex; + (*mutex)->handle = CreateMutex(NULL, FALSE, NULL); + + } +#endif + } + + apr_pool_cleanup_register((*mutex)->pool, (*mutex), thread_mutex_cleanup, + apr_pool_cleanup_null); + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_thread_mutex_lock(apr_thread_mutex_t *mutex) +{ + if (mutex->type == thread_mutex_critical_section) { + EnterCriticalSection(&mutex->section); + } + else { + DWORD rv = WaitForSingleObject(mutex->handle, INFINITE); + if ((rv != WAIT_OBJECT_0) && (rv != WAIT_ABANDONED)) { + return (rv == WAIT_TIMEOUT) ? APR_EBUSY : apr_get_os_error(); + } + } + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_thread_mutex_trylock(apr_thread_mutex_t *mutex) +{ + if (mutex->type == thread_mutex_critical_section) { + if (!TryEnterCriticalSection(&mutex->section)) { + return APR_EBUSY; + } + } + else { + DWORD rv = WaitForSingleObject(mutex->handle, 0); + if ((rv != WAIT_OBJECT_0) && (rv != WAIT_ABANDONED)) { + return (rv == WAIT_TIMEOUT) ? APR_EBUSY : apr_get_os_error(); + } + } + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_thread_mutex_timedlock(apr_thread_mutex_t *mutex, + apr_interval_time_t timeout) +{ + if (mutex->type != thread_mutex_critical_section) { + DWORD rv, timeout_ms = 0; + apr_interval_time_t t = timeout; + + do { + if (t > 0) { + /* Given timeout is 64bit usecs whereas Windows timeouts are + * 32bit msecs and below INFINITE (2^32 - 1), so we may need + * multiple timed out waits... + */ + if (t > apr_time_from_msec(INFINITE - 1)) { + timeout_ms = INFINITE - 1; + t -= apr_time_from_msec(INFINITE - 1); + } + else { + timeout_ms = (DWORD)apr_time_as_msec(t); + t = 0; + } + } + rv = WaitForSingleObject(mutex->handle, timeout_ms); + } while (rv == WAIT_TIMEOUT && t > 0); + + if ((rv != WAIT_OBJECT_0) && (rv != WAIT_ABANDONED)) { + return (rv == WAIT_TIMEOUT) ? APR_TIMEUP : apr_get_os_error(); + } + return APR_SUCCESS; + } + + return APR_ENOTIMPL; +} + +APR_DECLARE(apr_status_t) apr_thread_mutex_unlock(apr_thread_mutex_t *mutex) +{ + if (mutex->type == thread_mutex_critical_section) { + LeaveCriticalSection(&mutex->section); + } + else if (mutex->type == thread_mutex_unnested_event) { + if (!SetEvent(mutex->handle)) { + return apr_get_os_error(); + } + } + else if (mutex->type == thread_mutex_nested_mutex) { + if (!ReleaseMutex(mutex->handle)) { + return apr_get_os_error(); + } + } + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_thread_mutex_destroy(apr_thread_mutex_t *mutex) +{ + return apr_pool_cleanup_run(mutex->pool, mutex, thread_mutex_cleanup); +} + +APR_POOL_IMPLEMENT_ACCESSOR(thread_mutex) + diff --git a/locks/win32/thread_rwlock.c b/locks/win32/thread_rwlock.c new file mode 100644 index 0000000..fd9d579 --- /dev/null +++ b/locks/win32/thread_rwlock.c @@ -0,0 +1,165 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "apr.h" +#include "apr_private.h" +#include "apr_general.h" +#include "apr_strings.h" +#include "apr_arch_thread_rwlock.h" +#include "apr_portable.h" + +static apr_status_t thread_rwlock_cleanup(void *data) +{ + apr_thread_rwlock_t *rwlock = data; + + if (! CloseHandle(rwlock->read_event)) + return apr_get_os_error(); + + if (! CloseHandle(rwlock->write_mutex)) + return apr_get_os_error(); + + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t)apr_thread_rwlock_create(apr_thread_rwlock_t **rwlock, + apr_pool_t *pool) +{ + *rwlock = apr_palloc(pool, sizeof(**rwlock)); + + (*rwlock)->pool = pool; + (*rwlock)->readers = 0; + + if (! ((*rwlock)->read_event = CreateEvent(NULL, TRUE, FALSE, NULL))) { + *rwlock = NULL; + return apr_get_os_error(); + } + + if (! ((*rwlock)->write_mutex = CreateMutex(NULL, FALSE, NULL))) { + CloseHandle((*rwlock)->read_event); + *rwlock = NULL; + return apr_get_os_error(); + } + + apr_pool_cleanup_register(pool, *rwlock, thread_rwlock_cleanup, + apr_pool_cleanup_null); + + return APR_SUCCESS; +} + +static apr_status_t apr_thread_rwlock_rdlock_core(apr_thread_rwlock_t *rwlock, + DWORD milliseconds) +{ + DWORD code = WaitForSingleObject(rwlock->write_mutex, milliseconds); + + if (code == WAIT_FAILED || code == WAIT_TIMEOUT) + return APR_FROM_OS_ERROR(code); + + /* We've successfully acquired the writer mutex, we can't be locked + * for write, so it's OK to add the reader lock. The writer mutex + * doubles as race condition protection for the readers counter. + */ + InterlockedIncrement(&rwlock->readers); + + if (! ResetEvent(rwlock->read_event)) + return apr_get_os_error(); + + if (! ReleaseMutex(rwlock->write_mutex)) + return apr_get_os_error(); + + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_thread_rwlock_rdlock(apr_thread_rwlock_t *rwlock) +{ + return apr_thread_rwlock_rdlock_core(rwlock, INFINITE); +} + +APR_DECLARE(apr_status_t) +apr_thread_rwlock_tryrdlock(apr_thread_rwlock_t *rwlock) +{ + return apr_thread_rwlock_rdlock_core(rwlock, 0); +} + +static apr_status_t +apr_thread_rwlock_wrlock_core(apr_thread_rwlock_t *rwlock, DWORD milliseconds) +{ + DWORD code = WaitForSingleObject(rwlock->write_mutex, milliseconds); + + if (code == WAIT_FAILED || code == WAIT_TIMEOUT) + return APR_FROM_OS_ERROR(code); + + /* We've got the writer lock but we have to wait for all readers to + * unlock before it's ok to use it. + */ + if (rwlock->readers) { + /* Must wait for readers to finish before returning, unless this + * is an trywrlock (milliseconds == 0): + */ + code = milliseconds + ? WaitForSingleObject(rwlock->read_event, milliseconds) + : WAIT_TIMEOUT; + + if (code == WAIT_FAILED || code == WAIT_TIMEOUT) { + /* Unable to wait for readers to finish, release write lock: */ + if (! ReleaseMutex(rwlock->write_mutex)) + return apr_get_os_error(); + + return APR_FROM_OS_ERROR(code); + } + } + + return APR_SUCCESS; +} + +APR_DECLARE(apr_status_t) apr_thread_rwlock_wrlock(apr_thread_rwlock_t *rwlock) +{ + return apr_thread_rwlock_wrlock_core(rwlock, INFINITE); +} + +APR_DECLARE(apr_status_t)apr_thread_rwlock_trywrlock(apr_thread_rwlock_t *rwlock) +{ + return apr_thread_rwlock_wrlock_core(rwlock, 0); +} + +APR_DECLARE(apr_status_t) apr_thread_rwlock_unlock(apr_thread_rwlock_t *rwlock) +{ + apr_status_t rv = 0; + + /* First, guess that we're unlocking a writer */ + if (! ReleaseMutex(rwlock->write_mutex)) + rv = apr_get_os_error(); + + if (rv == APR_FROM_OS_ERROR(ERROR_NOT_OWNER)) { + /* Nope, we must have a read lock */ + if (rwlock->readers && + ! InterlockedDecrement(&rwlock->readers) && + ! SetEvent(rwlock->read_event)) { + rv = apr_get_os_error(); + } + else { + rv = 0; + } + } + + return rv; +} + +APR_DECLARE(apr_status_t) apr_thread_rwlock_destroy(apr_thread_rwlock_t *rwlock) +{ + return apr_pool_cleanup_run(rwlock->pool, rwlock, thread_rwlock_cleanup); +} + +APR_POOL_IMPLEMENT_ACCESSOR(thread_rwlock) |