bslmt_threadutilimpl_win32.h

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/// @file bslmt_threadutilimpl_win32.h
///
/// The content of this file has been pre-processed for Doxygen.
///
 
 
// bslmt_threadutilimpl_win32.h                                       -*-C++-*-
#ifndef INCLUDED_BSLMT_THREADUTILIMPL_WIN32
#define INCLUDED_BSLMT_THREADUTILIMPL_WIN32
 
#include <bsls_ident.h>
BSLS_IDENT("$Id: $")
 
/// @defgroup bslmt_threadutilimpl_win32 bslmt_threadutilimpl_win32
/// @brief  Provide a win32 implementation of `bslmt::ThreadUtil`.
/// @addtogroup bsl
/// @{
/// @addtogroup bslmt
/// @{
/// @addtogroup bslmt_threadutilimpl_win32
/// @{
///
/// <h1> Outline </h1>
/// * <a href="#bslmt_threadutilimpl_win32-purpose"> Purpose</a>
/// * <a href="#bslmt_threadutilimpl_win32-classes"> Classes </a>
/// * <a href="#bslmt_threadutilimpl_win32-description"> Description </a>
///   * <a href="#bslmt_threadutilimpl_win32-supported-clock-types"> Supported Clock-Types </a>
///   * <a href="#bslmt_threadutilimpl_win32-usage"> Usage </a>
///
/// # Purpose {#bslmt_threadutilimpl_win32-purpose}
/// Provide a win32 implementation of `bslmt::ThreadUtil`.
///
/// # Classes {#bslmt_threadutilimpl_win32-classes}
///
/// -  bslmt::ThreadUtilImpl<Win32Threads>: win32 specialization
///
/// @see  bslmt_threadutil
///
/// # Description {#bslmt_threadutilimpl_win32-description}
/// This component provides an implementation of
/// `bslmt::ThreadUtil` for Windows (win32),
/// `bslmt::ThreadUtilImpl<Win32Threads>`, via the template specialization:
/// @code
/// bslmt::ThreadUtilImpl<Platform::Win32Threads>
/// @endcode
/// This template class should not be used (directly) by client code.  Clients
/// should instead use `bslmt::ThreadUtil`.
///
/// ## Supported Clock-Types {#bslmt_threadutilimpl_win32-supported-clock-types}
///
///
/// `bsls::SystemClockType` supplies the enumeration indicating the system clock
/// on which timeouts supplied to other methods should be based.  If the clock
/// type indicated at construction is `bsls::SystemClockType::e_REALTIME`, the
/// `absTime` argument passed to the `timedWait` method of the various
/// synchronization primitives offered in `bslmt` should be expressed as an
/// *absolute* offset since 00:00:00 UTC, January 1, 1970 (which matches the
/// epoch used in `bsls::SystemTime::now(bsls::SystemClockType::e_REALTIME)`.
/// If the clock type indicated at construction is
/// `bsls::SystemClockType::e_MONOTONIC`, the `absTime` argument passed to the
/// `timedWait` method of the various synchronization primitives offered in
/// `bslmt` should be expressed as an *absolute* offset since the epoch of this
/// clock (which matches the epoch used in
/// `bsls::SystemTime::now(bsls::SystemClockType::e_MONOTONIC)`.
///
/// ## Usage {#bslmt_threadutilimpl_win32-usage}
///
///
/// This component is an implementation detail of `bslmt` and is *not* intended
/// for direct client use.  It is subject to change without notice.  As such, a
/// usage example is not provided.
/// @}
/** @} */
/** @} */
 
/** @addtogroup bsl
 * @{
 */
/** @addtogroup bslmt
 * @{
 */
/** @addtogroup bslmt_threadutilimpl_win32
 * @{
 */
 
#include <bslscm_version.h>
 
#include <bslmt_platform.h>
 
#ifdef BSLMT_PLATFORM_WIN32_THREADS
 
// Platform-specific implementation starts here.
 
#include <bslmt_saturatedtimeconversionimputil.h>
#include <bslmt_threadattributes.h>
 
#include <bsls_assert.h>
#include <bsls_systemclocktype.h>
#include <bsls_timeinterval.h>
#include <bsls_types.h>
 
#include <bsl_string.h>
 
typedef unsigned long DWORD;
typedef int BOOL;
typedef void *HANDLE;
 
extern "C" {
 
    __declspec(dllimport) void __stdcall Sleep(
                DWORD dwMilliseconds
    );
 
    __declspec(dllimport) DWORD __stdcall SleepEx(
                DWORD dwMilliseconds,
                BOOL bAlertable
    );
 
    __declspec(dllimport) DWORD __stdcall GetCurrentThreadId(
                void
    );
 
    __declspec(dllimport) HANDLE __stdcall GetCurrentThread(
                void
    );
 
    __declspec(dllimport) void* __stdcall TlsGetValue(
                DWORD dwTlsIndex
    );
 
    __declspec(dllimport) BOOL __stdcall TlsSetValue(
                DWORD dwTlsIndex,
                void *lpTlsValue
    );
 
};
 
 
 
extern "C" {
    /// `bslmt_ThreadFunction` is an alias for a function type taking a
    /// single `void` pointer argument and returning `void *`.  Such
    /// functions are suitable to be specified as thread entry point
    /// functions to `bslmt::ThreadUtil::create`.
    typedef void *(*bslmt_ThreadFunction)(void *);
 
    /// `bslmt_KeyDestructorFunction` is an alias for a function type taking
    /// a single `void` pointer argument and returning `void`.  Such
    /// functions are suitable to be specified as thread-specific key
    /// destructor functions to `bslmt::ThreadUtil::createKey`.
    typedef void (*bslmt_KeyDestructorFunction)(void *);
}
 
namespace bslmt {
 
template <class THREAD_POLICY>
struct ThreadUtilImpl;
 
               // ============================================
               // class ThreadUtilImpl<Platform::Win32Threads>
               // ============================================
 
/// This class provides a full specialization of 'ThreadUtilImpl' for
/// Windows.
template <>
struct ThreadUtilImpl<Platform::Win32Threads> {
 
    // TYPES
 
    /// Representation of a thread handle.  If a thread is created as
    /// joinable, then a duplicate of to original handle is created to be
    /// used in calls to `join` and `detach`.
    struct Handle {
 
        HANDLE d_handle;  // win32 thread handle
 
        DWORD  d_id;      // duplicate of thread handle used for joinable
                          // threads
    };
 
    typedef HANDLE NativeHandle;
        // Native WIN32 thread handle type
 
    typedef DWORD  Id;
        // Win32 thread Id type
 
    typedef DWORD  Key;
        // Win32 thread specific key(TLS index)
 
    // CLASS METHODS
    static const Handle INVALID_HANDLE;
 
    /// Create a new thread of program control having the attributes
    /// specified by `attribute`, that invokes the specified `function` with
    /// a single argument specified by `userData` and load into the
    /// specified `threadHandle`, an identifier that may be used to refer to
    /// the thread in future calls to this utility.  Return 0 on success,
    /// and a non-zero value otherwise.  The behavior is undefined if
    /// `thread` is 0.  Note that unless explicitly "detached"(`detach`), or
    /// unless the `BSLMT_CREATE_DETACHED` attribute is specified, a call to
    /// `join` must be made once the thread terminates to reclaim any system
    /// resources associated with the newly created identifier.
    static int create(Handle                  *thread,
                      const ThreadAttributes&  attribute,
                      bslmt_ThreadFunction     function,
                      void                    *userData);
 
    /// Create a new thread of program control having platform specific
    /// default attributes(i.e., "stack size", "scheduling priority"), that
    /// invokes the specified `function` with a single argument specified by
    /// `userData`, and load into the specified `threadHandle`, an
    /// identifier that may be used to refer to the thread in future calls
    /// to this utility.  Return 0 on success, and a non-zero value
    /// otherwise.  The behavior is undefined if `thread` is 0.  Note that
    /// unless explicitly "detached"(`detach`), a call to `join` must be
    /// made once the thread terminates to reclaim any system resources
    /// associated with the newly created identifier.
    static int create(Handle               *thread,
                      bslmt_ThreadFunction  function,
                      void                 *userData);
 
    /// Return the minimum available priority for the `policy`, where
    /// `policy` is of type `ThreadAttributes::SchedulingPolicy`.  Return
    /// `ThreadAttributes::BSLMT_UNSET_PRIORITY` if the minimum scheduling
    /// priority cannot be determined.  Note that, for some platform /
    /// policy combinations, `getMinSchedulingPriority(policy)` and
    /// `getMaxSchedulingPriority(policy)` return the same value.
    static int getMinSchedulingPriority(
                                    ThreadAttributes::SchedulingPolicy policy);
 
    /// Return the maximum available priority for the `policy`, where
    /// `policy` is of type `ThreadAttributes::SchedulingPolicy`.  Return
    /// `ThreadAttributes::BSLMT_UNSET_PRIORITY` if the maximum scheduling
    /// priority cannot be determined.  Note that, for some platform /
    /// policy combinations, `getMinSchedulingPriority(policy)` and
    /// `getMaxSchedulingPriority(policy)` return the same value.
    static int getMaxSchedulingPriority(
                                    ThreadAttributes::SchedulingPolicy policy);
 
    /// Load the name of the current thread into the specified `threadName`.
    /// Note that this method clears `*threadName` as thread naming is not
    /// implemented on Windows.
    static void getThreadName(bsl::string *threadName);
 
    /// Suspend execution of the current thread until the thread specified
    /// by `threadHandle` terminates, and reclaim any system resources
    /// associated with the specified `threadHandle`.  Return 0 on success,
    /// and a non-zero value otherwise.  If the specified `status` is not 0,
    /// load into the specified `status`, the value returned by the
    /// specified `thread`.
    static int join(Handle& thread, void **status = 0);
 
    /// Put the current thread to the end of the scheduler's queue and
    /// schedule another thread to run.  This allows cooperating threads of
    /// the same priority to share CPU resources equally.
    static void yield();
 
    /// Set the name of the current thread to the specified `threadName`.
    /// On Windows this function has no effect.
    static void setThreadName(const bslstl::StringRef&  threadName);
 
    /// Suspend execution of the current thread for a period of at least the
    /// specified `sleepTime` (relative time).  Note that the actual time
    /// suspended depends on many factors including system scheduling, and
    /// system timer resolution.  On the win32 platform the sleep timer has
    /// a resolution of 1 millisecond.
    static void sleep(const bsls::TimeInterval& sleepTime);
 
    /// Suspend execution of the current thread for a period of at least the
    /// specified `seconds` and `microseconds` (relative time).  Note that
    /// the actual time suspended depends on many factors including system
    /// scheduling, and system timer resolution.  On the win32 platform the
    /// sleep timer has a resolution of 1 millisecond.
    static void microSleep(int microseconds, int seconds = 0);
 
    /// Suspend execution of the current thread until the specified
    /// `absoluteTime`.  Optionally specify `clockType` which determines the
    /// epoch from which the interval `absoluteTime` is measured (see
    /// {Supported Clock-Types} in the component documentation).  Return 0
    /// on success, and a non-zero value otherwise.  The behavior is
    /// undefined unless `absoluteTime` represents a time after January 1,
    /// 1970 and before the end of December 31, 9999 (i.e., a time interval
    /// greater than or equal to 0, and less than 253,402,300,800 seconds).
    /// Note that the actual time suspended depends on many factors
    /// including system scheduling and system timer resolution.
    static int sleepUntil(const bsls::TimeInterval&   absoluteTime,
                          bsls::SystemClockType::Enum clockType
                                          = bsls::SystemClockType::e_REALTIME);
 
    /// Exit the current thread and return the specified `status`.  If the
    /// current thread is not "detached", then a call to `join` must be made
    /// to reclaim any resources used by the thread, and to retrieve the
    /// exit status.  Note that generally, the preferred method of exiting a
    /// thread is to return form the entry point function.
    static void exit(void *status);
 
    /// Return a thread `Handle` that can be used to refer to the current
    /// thread.  The handle can be specified to any function that supports
    /// operations on itself (e.g., `detach`, `areEqual`).  Note that the
    /// returned handle is only valid in the context of the calling thread.
    static Handle self();
 
    /// "Detach" the thread identified by `threadHandle`, such that when it
    /// terminates, the resources associated the thread will automatically
    /// be reclaimed.  Note that once a thread is "detached", it is no
    /// longer possible to `join` the thread to retrieve the its exit
    /// status.
    static int detach(Handle& threadHandle);
 
    /// Return the platform specific identifier associated with the thread
    /// specified by `threadHandle`.  Note that the returned native handle
    /// may not be a globally unique identifier for the thread (see
    /// `selfIdAsUint`).
    static NativeHandle nativeHandle(const Handle& threadHandle);
 
    /// Return `true` if the specified `a` and `b` thread handles identify
    /// the same thread and a `false` value otherwise.
    static bool areEqual(const Handle& a, const Handle& b);
 
    /// Return an identifier that can be used to uniquely identify the
    /// current thread within the current process.  Note that the id is only
    /// valid until the thread terminates and may be reused thereafter.
    static Id selfId();
 
    /// Return an integral identifier that can be used to uniquely identify
    /// the current thread within the current process.  This representation
    /// is particularly useful for logging purposes.  Note that this value
    /// is only valid until the thread terminates and may be reused
    /// thereafter.
    ///
    /// DEPRECATED: Use `selfIdAsUint64` instead.
    static bsls::Types::Uint64 selfIdAsInt();
 
    /// Return an integral identifier that can be used to uniquely identify
    /// the current thread within the current process.  This representation
    /// is particularly useful for logging purposes.  Note that this value
    /// is only valid until the thread terminates and may be reused
    /// thereafter.
    static bsls::Types::Uint64 selfIdAsUint64();
 
    /// Return the unique identifier of the thread having the specified
    /// `threadHandle` within the current process.  Note that this value is
    /// only valid until the thread terminates and may be reused thereafter.
    static Id handleToId(const Handle& threadHandle);
 
    /// Return the unique integral identifier of a thread uniquely
    /// identified by the specified `threadId` within the current process.
    /// Note that this representation is particularly useful for logging
    /// purposes.  Also note that this value is only valid until the thread
    /// terminates and may be reused thereafter.
    static bsls::Types::Uint64 idAsUint64(const Id& threadId);
 
    /// Return the unique integral identifier of a thread uniquely
    /// identified by the specified `threadId` within the current process.
    /// Note that this representation is particularly useful for logging
    /// purposes.  Also note that this value is only valid until the thread
    /// terminates and may be reused thereafter.
    ///
    /// DEPRECATED: use `idAsUint64`.
    static int idAsInt(const Id& threadId);
 
    /// Return `true` if the specified `a` and `b` thread id identify the
    /// same thread and `false` otherwise.
    static bool areEqualId(const Id& a, const Id& b);
 
    /// Store into the specified `key`, an identifier that can be used to
    /// associate(`setSpecific`) and retrieve(`getSpecific`) a single
    /// thread-specific pointer value.  Associated with the identifier,the
    /// optional `destructor` if a non-zero value is specified.  Return 0 on
    /// success, and a non-zero value otherwise.
    static int createKey(Key *key, bslmt_KeyDestructorFunction destructor);
 
    /// Delete the specified thread-specific `key`.  Note that deleting a
    /// key does not delete any data that is currently associated with the
    /// key in the calling thread or any other thread.
    static int deleteKey(Key& key);
 
    /// Return the value associated with the specified thread-specific
    /// `key`.  Note that if the key is not valid, a value of zero is
    /// returned, which is indistinguishable from a valid key with a 0
    /// value.
    static void *getSpecific(const Key& key);
 
    /// Associate the specified `value` with the specified thread-specific
    /// `key`.  Return 0 on success, and a non-zero value otherwise.
    static int setSpecific(const Key& key, const void *value);
 
    /// Return the number of concurrent threads supported by the
    /// implementation on success, and 0 otherwise.
    static unsigned int hardwareConcurrency();
};
 
// FREE OPERATORS
 
/// Return `true` if the specified `lhs` and `rhs` thread handles have the
/// same value, and `false` otherwise.
bool operator==(const ThreadUtilImpl<Platform::Win32Threads>::Handle& lhs,
                const ThreadUtilImpl<Platform::Win32Threads>::Handle& rhs);
 
/// Return `true` if the specified `lhs` and `rhs` thread handles do not
/// have the same value, and `false` otherwise.
bool operator!=(const ThreadUtilImpl<Platform::Win32Threads>::Handle& lhs,
                const ThreadUtilImpl<Platform::Win32Threads>::Handle& rhs);
 
 
// ============================================================================
//                             INLINE DEFINITIONS
// ============================================================================
 
               // --------------------------------------------
               // class ThreadUtilImpl<Platform::Win32Threads>
               // --------------------------------------------
 
// CLASS METHODS
inline
int ThreadUtilImpl<bslmt::Platform::Win32Threads>::
    getMinSchedulingPriority(ThreadAttributes::SchedulingPolicy)
{
    return ThreadAttributes::e_UNSET_PRIORITY;
}
 
inline
int ThreadUtilImpl<bslmt::Platform::Win32Threads>::
    getMaxSchedulingPriority(ThreadAttributes::SchedulingPolicy)
{
    return ThreadAttributes::e_UNSET_PRIORITY;
}
 
inline
void ThreadUtilImpl<bslmt::Platform::Win32Threads>::yield()
{
    ::SleepEx(0, 0);
}
 
inline
void ThreadUtilImpl<bslmt::Platform::Win32Threads>::sleep(
                                           const bsls::TimeInterval& sleepTime)
 
{
    DWORD milliSeconds;
    SaturatedTimeConversionImpUtil::toMillisec(&milliSeconds, sleepTime);
 
    ::Sleep(milliSeconds);
}
 
inline
void ThreadUtilImpl<bslmt::Platform::Win32Threads>::microSleep(
                                                                 int microsecs,
                                                                 int seconds)
{
    enum { k_MILLION = 1000 * 1000 };
 
    bsls::TimeInterval ti((microsecs / k_MILLION) + seconds,
                         (microsecs % k_MILLION) * 1000);
    DWORD milliSeconds;
    SaturatedTimeConversionImpUtil::toMillisec(&milliSeconds, ti);
 
    ::Sleep(milliSeconds);
}
 
inline
ThreadUtilImpl<bslmt::Platform::Win32Threads>::Handle
ThreadUtilImpl<bslmt::Platform::Win32Threads>::self()
{
    Handle h;
    h.d_id     = GetCurrentThreadId();
    h.d_handle = GetCurrentThread();
    return h;
}
 
inline
ThreadUtilImpl<bslmt::Platform::Win32Threads>::NativeHandle
ThreadUtilImpl<bslmt::Platform::Win32Threads>::nativeHandle(
                                                          const Handle& handle)
{
    return handle.d_handle;
}
 
inline
ThreadUtilImpl<bslmt::Platform::Win32Threads>::Id
ThreadUtilImpl<bslmt::Platform::Win32Threads>::selfId()
{
    return GetCurrentThreadId();
}
 
inline
bsls::Types::Uint64
ThreadUtilImpl<bslmt::Platform::Win32Threads>::selfIdAsInt()
{
    return idAsInt(selfId());
}
 
inline
bsls::Types::Uint64
ThreadUtilImpl<bslmt::Platform::Win32Threads>::selfIdAsUint64()
{
    return idAsUint64(selfId());
}
 
inline
ThreadUtilImpl<bslmt::Platform::Win32Threads>::Id
ThreadUtilImpl<bslmt::Platform::Win32Threads>::handleToId(
                                                    const Handle& threadHandle)
{
    return threadHandle.d_id;
}
 
inline
bsls::Types::Uint64
ThreadUtilImpl<bslmt::Platform::Win32Threads>::idAsUint64(
                                                            const Id& threadId)
{
    return static_cast<bsls::Types::Uint64>(threadId);
}
 
inline
int ThreadUtilImpl<bslmt::Platform::Win32Threads>::idAsInt(
                                                            const Id& threadId)
{
    return static_cast<int>(threadId);
}
 
inline
bool ThreadUtilImpl<bslmt::Platform::Win32Threads>::areEqualId(
                                                                   const Id& a,
                                                                   const Id& b)
{
    return a == b;
}
 
inline
void *ThreadUtilImpl<bslmt::Platform::Win32Threads>::getSpecific(
                                                                const Key& key)
{
    return TlsGetValue(key);
}
 
inline
int ThreadUtilImpl<bslmt::Platform::Win32Threads>::setSpecific(
                                                             const Key&  key,
                                                             const void *value)
{
    return 0 == TlsSetValue(key, (void*)value) ? 1 : 0;
}
 
}  // close package namespace
 
                          // ----------------------
                          // ThreadUtilImpl::Handle
                          // ----------------------
 
// FREE OPERATORS
inline
bool bslmt::operator==(
       const bslmt::ThreadUtilImpl<bslmt::Platform::Win32Threads>::Handle& lhs,
       const bslmt::ThreadUtilImpl<bslmt::Platform::Win32Threads>::Handle& rhs)
{
    return bslmt::ThreadUtilImpl<Platform::Win32Threads>::areEqual(lhs, rhs);
}
 
inline
bool bslmt::operator!=(
       const bslmt::ThreadUtilImpl<bslmt::Platform::Win32Threads>::Handle& lhs,
       const bslmt::ThreadUtilImpl<bslmt::Platform::Win32Threads>::Handle& rhs)
{
    return !(lhs == rhs);
}
 
 
 
#endif  // BSLMT_PLATFORM_WIN32_THREADS
 
#endif
 
// ----------------------------------------------------------------------------
// Copyright 2015 Bloomberg Finance L.P.
//
// Licensed 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.
// ----------------------------- END-OF-FILE ----------------------------------
 
/** @} */
/** @} */
/** @} */