pasync.h

Index

    #ifndef __PASYNC_H__
    #define __PASYNC_H__

    #ifdef WIN32
    #  define _WINSOCKAPI_   // prevent inclusion of winsock.h, since we need winsock2.h
    #  include <windows.h>
    #else
    #  include <pthread.h>
    #  ifndef __bsdi__
    #    include <semaphore.h>
    #  endif
    #endif

    #ifndef __PPORT_H__
    #include "pport.h"
    #endif

    #ifndef __PTYPES_H__
    #include "ptypes.h"
    #endif

    PTYPES_BEGIN

    //
    //  Summary of implementation:
    //
    //  atomic increment/decrement/exchange
    //    MSVC/BCC/i386: internal, asm
    //    GCC/i386: internal, asm
    //    GCC/PowerPC: internal, asm
    //    GCC/SPARC: internal, asm
    //    Other: internal, mutex hash table
    //
    //  mutex
    //    Win32: Critical section
    //    Other: POSIX mutex
    //
    //  trigger
    //    Win32: Event
    //    Other: internal, POSIX condvar/mutex
    //
    //  rwlock:
    //    Win32: internal, Event/mutex
    //    MacOS: internal, POSIX condvar/mutex
    //    Other: POSIX rwlock
    //
    //  semaphore:
    //    Win32: = timedsem
    //    MacOS: = timedsem
    //    Other: POSIX semaphore
    //
    //  timedsem (with timed waiting):
    //    Win32: Semaphore
    //    Other: internal, POSIX mutex/condvar
    //

    #ifdef _MSC_VER
    #pragma pack(push, 4)
    #endif

    #ifdef WIN32
       typedef int pthread_id_t;
       typedef HANDLE pthread_t;
    #else
       typedef pthread_t pthread_id_t;
    #endif

    void psleep(uint milliseconds);
    bool pthrequal(pthread_id_t id);  // note: this is NOT the thread handle, use thread::get_id()
    pthread_id_t pthrself();          // ... same

    // -------------------------------------------------------------------- //
    // --- mutex ---------------------------------------------------------- //
    // -------------------------------------------------------------------- //

    #ifdef WIN32

    struct mutex: public noncopyable
    {
    protected:
        CRITICAL_SECTION critsec;
    public:
        mutex()         { InitializeCriticalSection(&;critsec); }
        ~mutex()        { DeleteCriticalSection(&critsec); }
        void enter()    { EnterCriticalSection(&critsec); }
        void leave()    { LeaveCriticalSection(&critsec); }
        void lock()     { enter(); }
        void unlock()   { leave(); }
    };

    #else

    struct mutex: public noncopyable
    {
    protected:
        pthread_mutex_t mtx;
    public:
        mutex()         { pthread_mutex_init(&mtx, 0); }
        ~mutex()        { pthread_mutex_destroy(&mtx); }
        void enter()    { pthread_mutex_lock(&mtx); }
        void leave()    { pthread_mutex_unlock(&mtx); }
        void lock()     { enter(); }
        void unlock()   { leave(); }
    };

    #endif

    //
    // scopelock
    //

    class scopelock: public noncopyable
    {
    protected:
        mutex* mtx;
    public:
        scopelock(mutex& imtx): mtx(&imtx)  { mtx->lock(); }
        ~scopelock()  { mtx->unlock(); }
    };

    //
    // mutex table for hashed memory locking (undocumented)
    //

    #define _MUTEX_HASH_SIZE     29      // a prime number for hashing

    #ifdef WIN32
    #  define pmemlock        mutex
    #  define pmementer(m)    (m)->lock()
    #  define pmemleave(m)    (m)->unlock()
    #else
    #  define _MTX_INIT       PTHREAD_MUTEX_INITIALIZER
    #  define pmemlock        pthread_mutex_t
    #  define pmementer       pthread_mutex_lock
    #  define pmemleave       pthread_mutex_unlock
    #endif

    extern pmemlock _mtxtable[_MUTEX_HASH_SIZE];

    #define pgetmemlock(addr) (_mtxtable + pintptr(addr) % _MUTEX_HASH_SIZE)

    // -------------------------------------------------------------------- //
    // --- trigger -------------------------------------------------------- //
    // -------------------------------------------------------------------- //

    #ifdef WIN32

    class trigger: public noncopyable
    {
    protected:
        HANDLE handle;      // Event object
    public:
        trigger(bool autoreset, bool state);
        ~trigger()          { CloseHandle(handle); }
        void wait()         { WaitForSingleObject(handle, INFINITE); }
        void post()         { SetEvent(handle); }
        void signal()       { post(); }
        void reset()        { ResetEvent(handle); }
    };

    #else

    class trigger: public noncopyable
    {
    protected:
        pthread_mutex_t mtx;
        pthread_cond_t cond;
        int state;
        bool autoreset;
    public:
        trigger(bool autoreset, bool state);
        ~trigger();
        void wait();
        void post();
        void signal()  { post(); }
        void reset();
    };

    #endif

    // -------------------------------------------------------------------- //
    // --- rwlock --------------------------------------------------------- //
    // -------------------------------------------------------------------- //

    #if defined(WIN32) || defined(__DARWIN__) || defined(__bsdi__)
    #  define __PTYPES_RWLOCK__
    #elif defined(linux)
       // on Linux rwlocks are included only with -D_GNU_SOURCE.
       // programs that don't use rwlocks, do not need to define
       // _GNU_SOURCE either.
    #  if defined(_GNU_SOURCE) || defined(__USE_UNIX98)
    #    define __POSIX_RWLOCK__
    #  endif
    #else
    #  define __POSIX_RWLOCK__
    #endif

    #ifdef __PTYPES_RWLOCK__

    struct rwlock: protected mutex
    {
    protected:
    #ifdef WIN32
        HANDLE  reading;    // Event object
        HANDLE  finished;   // Event object
        int     readcnt;
        int     writecnt;
    #else
        pthread_mutex_t mtx;
        pthread_cond_t readcond;
        pthread_cond_t writecond;
        int locks;
        int writers;
        int readers;
    #endif
    public:
        rwlock();
        ~rwlock();
        void rdlock();
        void wrlock();
        void unlock();
        void lock()     { wrlock(); }
    };

    #elif defined(__POSIX_RWLOCK__)

    struct rwlock: public noncopyable
    {
    protected:
        pthread_rwlock_t rw;
    public:
        rwlock();
        ~rwlock()       { pthread_rwlock_destroy(&rw); }
        void rdlock()   { pthread_rwlock_rdlock(&rw); }
        void wrlock()   { pthread_rwlock_wrlock(&rw); }
        void unlock()   { pthread_rwlock_unlock(&rw); }
        void lock()     { wrlock(); }
    };

    #endif

    #if defined(__PTYPES_RWLOCK__) || defined(__POSIX_RWLOCK__)

    //
    // scoperead & scopewrite
    //

    class scoperead: public noncopyable
    {
    protected:
        rwlock* rw;
    public:
        scoperead(rwlock& irw): rw(&irw)  { rw->rdlock(); }
        ~scoperead()  { rw->unlock(); }
    };

    class scopewrite: public noncopyable
    {
    protected:
        rwlock* rw;
    public:
        scopewrite(rwlock& irw): rw(&irw)  { rw->wrlock(); }
        ~scopewrite()  { rw->unlock(); }
    };

    #endif

    // -------------------------------------------------------------------- //
    // --- semaphore ------------------------------------------------------ //
    // -------------------------------------------------------------------- //

    #if defined(WIN32) || defined(__DARWIN__) || defined(__bsdi__)
    #  define __SEM_TO_TIMEDSEM__
    #endif

    #ifdef __SEM_TO_TIMEDSEM__

    // map ordinary semaphore to timed semaphore

    class timedsem;
    typedef timedsem semaphore;

    #else

    class semaphore: public unknown
    {
    protected:
        sem_t handle;
    public:
        semaphore(int initvalue);
        virtual ~semaphore();

        void wait();
        void post();
        void signal()  { post(); }
    };

    #endif

    class timedsem: public unknown
    {
    protected:
    #ifdef WIN32
        HANDLE handle;
    #else
        int count;
        pthread_mutex_t mtx;
        pthread_cond_t cond;
    #endif
    public:
        timedsem(int initvalue);
        virtual ~timedsem();
        bool wait(int msecs = -1);
        void post();
        void signal()  { post(); }
    };

    // -------------------------------------------------------------------- //
    // --- thread --------------------------------------------------------- //
    // -------------------------------------------------------------------- //

    class thread: public unknown
    {
    protected:
    #ifdef WIN32
        unsigned id;
    #endif
        pthread_t  handle;
        int  autofree;
        int  running;
        int  signaled;
        int  finished;
        int  freed;
        int  reserved;   // for priorities
        timedsem relaxsem;

        virtual void execute() = 0;
        virtual void cleanup();

        bool relax(int msecs) { return relaxsem.wait(msecs); }

        friend void _threadepilog(thread* thr);

    #ifdef WIN32
        friend unsigned __stdcall _threadproc(void* arg);
    #else
        friend void* _threadproc(void* arg);
    #endif

    public:
        thread(bool iautofree);
        virtual ~thread();

    #ifdef WIN32
        pthread_id_t get_id()   { return int(id); }
    #else
        pthread_id_t get_id()   { return handle; }
    #endif

        bool get_running()    { return running != 0; }
        bool get_finished()   { return finished != 0; }
        bool get_signaled()   { return signaled != 0; }

        void start();
        void signal();
        void waitfor();
    };

    // -------------------------------------------------------------------- //
    // --- jobqueue & msgqueue -------------------------------------------- //
    // -------------------------------------------------------------------- //

    const int MSG_USER = 0;
    const int MSG_QUIT = -1;

    const int DEF_QUEUE_LIMIT = 5000;

    class message: public unknown
    {
    protected:
        message* next;          // next in the message chain, used internally
        semaphore* sync;        // used internally by msgqueue::send(), when called from a different thread
        friend class jobqueue;  // my friends, job queue and message queue...
        friend class msgqueue;
    public:
        int id;
        pintptr param;
        pintptr result;
        message(int iid, pintptr iparam = 0);
        virtual ~message();
    };

    class jobqueue: public noncopyable
    {
    private:
        int       limit;        // queue limit
        message*  head;         // queue head
        message*  tail;         // queue tail
        int       qcount;       // number of items in the queue
        timedsem  sem;          // queue semaphore
        timedsem  ovrsem;       // overflow semaphore
        mutex     qlock;        // critical sections in enqueue and dequeue

    protected:
        bool enqueue(message* msg, int timeout = -1);
        bool push(message* msg, int timeout = -1);
        message* dequeue(bool safe = true, int timeout = -1);
        void purgequeue();

    public:
        jobqueue(int ilimit = DEF_QUEUE_LIMIT);
        virtual ~jobqueue();

        int  get_count() const  { return qcount; }
        int  get_limit() const  { return limit; }

        bool post(message* msg, int timeout = -1);
        bool post(int id, pintptr param = 0, int timeout = -1);
        bool posturgent(message* msg, int timeout = -1);
        bool posturgent(int id, pintptr param = 0, int timeout = -1);
        message* getmessage(int timeout = -1);

    #ifdef PTYPES19_COMPAT
        int  msgsavail() const  { return get_count(); }
    #endif
    };

    template <class T> class tjobqueue: protected jobqueue
    {
    public:
        tjobqueue(int ilimit = DEF_QUEUE_LIMIT);

        int  get_count() const                      { return jobqueue::get_count(); }
        int  get_limit() const                      { return jobqueue::get_limit(); }
        bool post(T* msg, int timeout = -1)         { return jobqueue::post(msg, timeout); }
        bool posturgent(T* msg, int timeout = -1)   { return jobqueue::posturgent(msg, timeout); }
        T*   getmessage(int timeout = -1)           { return (T*)jobqueue::getmessage(timeout); }
    };

    class msgqueue: protected jobqueue
    {
    private:
        mutex thrlock;          // lock for the queue processing
        pthread_id_t owner;     // thread ID of the queue processing thread

        pintptr finishmsg(message* msg);
        void handlemsg(message* msg);
        void takeownership();

    protected:
        bool quit;

        void defhandler(message& msg);
        virtual void msghandler(message& msg) = 0;

    public:
        msgqueue(int ilimit = DEF_QUEUE_LIMIT);
        virtual ~msgqueue();

        // functions calling from the owner thread:
        void processone();  // process one message, may hang if no msgs in the queue
        void processmsgs(); // process all available messages and return
        void run();         // process messages until MSG_QUIT

        // functions calling from any thread:
        int  get_count() const                                        { return jobqueue::get_count(); }
        int  get_limit() const                                        { return jobqueue::get_limit(); }
        bool post(message* msg, int timeout = -1)                     { return jobqueue::post(msg, timeout); }
        bool post(int id, pintptr param = 0, int timeout = -1)        { return jobqueue::post(id, param, timeout); }
        bool posturgent(message* msg, int timeout = -1)               { return jobqueue::posturgent(msg, timeout); }
        bool posturgent(int id, pintptr param = 0, int timeout = -1)  { return jobqueue::posturgent(id, param, timeout); }
        pintptr send(message* msg);
        pintptr send(int id, pintptr param = 0);

    #ifdef PTYPES19_COMPAT
        int  msgsavail() const  { return get_count(); }
    #endif
    };

    #ifdef _MSC_VER
    #pragma pack(pop)
    #endif

    PTYPES_END

    #endif // __PASYNC_H__