Big-Data-HPC-Platform/system/jlib/jthread.hpp

/*##############################################################################

    HPCC SYSTEMS software Copyright (C) 2012 HPCC Systems®.

    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.
############################################################################## */



#ifndef __JTHREAD__
#define __JTHREAD__

#include "jiface.hpp"
#include "jmutex.hpp"
#include "jexcept.hpp"
#include "jhash.hpp"

#ifdef _WIN32
#define DEFAULT_THREAD_PRIORITY THREAD_PRIORITY_NORMAL
#else
// no thread priority handling?
#endif

interface jlib_decl IThread : public IInterface
{
    virtual void start() = 0;
    virtual int run() = 0;
};

interface jlib_decl IThreadName 
{
    virtual const char *get()=0;
};



extern jlib_decl void addThreadExceptionHandler(IExceptionHandler *handler);
extern jlib_decl void removeThreadExceptionHandler(IExceptionHandler *handler);
extern jlib_decl void enableThreadSEH();
extern jlib_decl void disableThreadSEH();

extern jlib_decl unsigned threadLogID();  // for use in logging

// A function registered via addThreadTermFunc will be called when the thread that registered that function
// terminates. Such a function should call on to the previously registered function (if any) - generally you
// would expect to store that value in thread-local storage.
// This can be used to ensure that thread-specific objects can be properly destructed.
// Note that threadpools also call the thread termination hook when each thread's main function terminates,
// so the hook function should clear any variables if necessary rather than assuming that they will be cleared
// at thread startup time.

typedef void (*ThreadTermFunc)();
extern jlib_decl ThreadTermFunc addThreadTermFunc(ThreadTermFunc onTerm);
extern jlib_decl void callThreadTerminationHooks();

//An exception safe way of ensuring that the thread termination hooks are called.
class jlib_decl QueryTerminationCleanup
{
public:
    inline ~QueryTerminationCleanup() { callThreadTerminationHooks(); }
};

class jlib_decl Thread : public CInterface, public IThread
{
private:
    ThreadId threadid;
    unsigned short stacksize; // in 4K blocks
    int prioritydelta;
    int nicelevel;

    bool alive;
    unsigned tidlog;
#ifdef _WIN32
    HANDLE hThread;
    static unsigned WINAPI _threadmain(LPVOID v);
#else
    static void *_threadmain(void *v);
#endif
    virtual int begin();
    void init(const char *name);
    void handleException(IException *e);
    void adjustNiceLevel();

protected:
    struct cThreadName: implements IThreadName
    {
        char *threadname;
        const char *get() { return threadname; }
    } cthreadname;
    IThreadName *ithreadname;
public:
#ifndef _WIN32
    Semaphore suspend;
    Semaphore starting;
#endif
    Semaphore stopped;

    IMPLEMENT_IINTERFACE;

    Thread(const char *_name) { init(_name); }
    Thread() { init(NULL); }
    ~Thread();

    void adjustPriority(int delta);
    bool isCurrentThread() const;
    void setNice(int nicelevel);
    void setStackSize(size32_t size);               // required stack size in bytes - called before start() (obviously)
    const char *getName() { const char *ret = ithreadname?ithreadname->get():NULL; return ret?ret:"unknown"; }
    bool isAlive() { return alive; }
    bool join(unsigned timeout=INFINITE);

    virtual void start();
    virtual void startRelease();        

    StringBuffer &getInfo(StringBuffer &str) { str.appendf("%8" I64F "X %6" I64F "d %u: %s",(__int64)threadid,(__int64)threadid,tidlog,getName()); return str; } 
    const char *getLogInfo(int &thandle,unsigned &tid) { 
#ifdef _WIN32
        thandle = (int)(memsize_t)hThread;
#elif defined __FreeBSD__ || defined __APPLE__
        thandle = (int)(memsize_t)threadid;
#else
        thandle = threadid; 
#endif
        tid = tidlog;
        return getName(); 
    }

    // run method not implemented - concrete derived classes must do so
    static  void setDefaultStackSize(size32_t size);    // NB under windows requires linker setting (/stack:)

    IThreadName *queryThreadName() { return ithreadname; }
    void setThreadName(IThreadName *name) { ithreadname = name; }

};

interface IThreaded
{
    virtual void main() = 0;
protected:
    virtual ~IThreaded() {}
};

// utility class, useful for containing a thread
class CThreaded : public Thread
{
    IThreaded *owner;
public:
    inline CThreaded(const char *name, IThreaded *_owner) : Thread(name), owner(_owner) { }
    inline CThreaded(const char *name) : Thread(name) { owner = NULL; }
    inline void init(IThreaded *_owner) { owner = _owner; start(); }
    virtual int run() { owner->main(); return 1; }
};

// Similar to above, but the underlying thread always remains running. This can make repeated start + join's significantly quicker
class jlib_decl CThreadedPersistent : public CInterface
{
    class CAThread : public Thread
    {
        CThreadedPersistent &owner;
    public:
        CAThread(CThreadedPersistent &_owner, const char *name) : Thread(name), owner(_owner) { }
        virtual int run() { owner.main(); return 1; }
    } athread;
    Owned<IException> exception;
    IThreaded *owner;
    Semaphore sem, joinSem;
    atomic_t state;
    bool halt;
    enum ThreadStates { s_ready, s_running, s_joining };

    void main();
public:
    CThreadedPersistent(const char *name, IThreaded *_owner);
    ~CThreadedPersistent();
    void start();
    bool join(unsigned timeout=INFINITE);
};


// Asynchronous 'for' utility class
// see HRPCUTIL.CPP for example of usage

class jlib_decl CAsyncFor
{
public:
    void For(unsigned num,unsigned maxatonce,bool abortFollowingException=false,bool shuffled=false);
    virtual void Do(unsigned idx=0)=0;
};

// ---------------------------------------------------------------------------
// Thread Pools
// ---------------------------------------------------------------------------

interface IPooledThread: extends IInterface                 // base class for deriving pooled thread (alternative to Thread)
{
public:
       virtual void init(void *param)=0;                    // called before main started (from within start)
       virtual void main()=0;                               // where threads code goes (param is passed from start)
       virtual bool stop()=0;                               // called to cause main to return, returns false if request rejected
       virtual bool canReuse()=0;                           // return true if object can be re-used (after stopped), otherwise released
};

interface IThreadFactory: extends IInterface                // factory for creating new pooled instances (called when pool empty)
{
       virtual IPooledThread *createNew()=0;
};

typedef IIteratorOf<IPooledThread> IPooledThreadIterator;
typedef unsigned PooledThreadHandle;

interface IThreadPool : extends IInterface
{
        virtual PooledThreadHandle start(void *param)=0;    // starts a new thread reuses stopped pool entries
        virtual PooledThreadHandle start(void *param,const char *name)=0;   // starts a new thread reuses stopped pool entries 
        virtual PooledThreadHandle start(void *param,const char *name,unsigned timeout)=0;  // starts a new thread reuses stopped pool entries, throws exception if can't start within timeout 
        virtual bool stop(PooledThreadHandle handle)=0;     // initiates stop on specified thread (may return false)
        virtual bool stopAll(bool tryall=false)=0;          // initiates stop on all threads, if tryall continues even if one or more fails
        virtual bool join(PooledThreadHandle handle,unsigned timeout=INFINITE)=0;
                                                            // waits for a single thread to terminate
        virtual bool joinAll(bool del=true,unsigned timeout=INFINITE)=0;    // waits for all threads in thread pool to terminate
                                                                            // if del true frees all pooled threads
        virtual IPooledThreadIterator *running()=0;                 // return an iterator for all currently running threads
        virtual unsigned runningCount()=0;                  // number of currently running threads
        virtual PooledThreadHandle startNoBlock(void *param)=0; // starts a new thread if it can do so without blocking, else throws exception
        virtual PooledThreadHandle startNoBlock(void *param,const char *name)=0;    // starts a new thread if it can do so without blocking, else throws exception
        virtual void setStartDelayTracing(unsigned secs) = 0;        // set start delay tracing period
};

extern jlib_decl IThreadPool *createThreadPool(
                                const char *poolname,       // trace name of pool
                                IThreadFactory *factory,    // factory for creating new thread instances
                                IExceptionHandler *exceptionHandler=NULL, // optional exception handler
                                unsigned defaultmax=50,     // maximum number of threads before starts blocking
                                unsigned delay=1000,        // maximum delay on each block
                                unsigned stacksize=0,       // stack size (bytes) 0 is default
                                unsigned timeoutOnRelease=INFINITE, // maximum time waited for thread to terminate on releasing pool
                                unsigned targetpoolsize=0           // target maximum size of pool (default same as defaultmax)   
                             );

extern jlib_decl StringBuffer &getThreadList(StringBuffer &str);
extern jlib_decl unsigned getThreadCount();
extern jlib_decl StringBuffer &getThreadName(int thandle,unsigned logtid,StringBuffer &name); // either thandle or tid should be 0

// Simple pipe process support
interface ISimpleReadStream;

#define START_FAILURE (199) // return code if program cannot be started

interface IPipeProcess: extends IInterface
{
    virtual bool run(const char *title,const char *prog, const char *dir,
                       bool hasinput,bool hasoutput,bool haserror=false,
                       size32_t stderrbufsize=0,                      // set to non-zero to automatically buffer stderror output
                       bool newProcessGroup=false) = 0;
    virtual bool hasInput() = 0;                                    // i.e. can write to pipe
    virtual size32_t write(size32_t sz, const void *buffer) = 0;    // write pipe process standard output
    virtual bool hasOutput() = 0;                                   // i.e. can read from pipe
    virtual size32_t read(size32_t sz, void *buffer) = 0;           // read from pipe process standard output
    virtual ISimpleReadStream *getOutputStream() = 0;               // read from pipe process standard output
    virtual bool hasError() = 0;                                    // i.e. can read from pipe stderr
    virtual size32_t readError(size32_t sz, void *buffer) = 0;      // read from pipe process standard error
    virtual ISimpleReadStream *getErrorStream() = 0;                // read from pipe process standard error

    virtual unsigned wait() = 0;                                    // returns return code
    virtual unsigned wait(unsigned timeoutms, bool &timedout) = 0;  // sets timedout to true if times out
    virtual void closeInput() = 0;                                  // indicate finished input to pipe
    virtual void closeOutput() = 0;                                 // indicate finished reading from pipe (generally called automatically)
    virtual void closeError() = 0;                                  // indicate finished reading from pipe stderr
    virtual void abort() = 0;
    virtual void notifyTerminated(HANDLE pid,unsigned retcode) = 0; // internal
    virtual HANDLE getProcessHandle() = 0;                          // used to auto kill
    virtual void setenv(const char *var, const char *value) = 0;  // Set a value to be passed in the called process environment
};

extern jlib_decl IPipeProcess *createPipeProcess(const char *allowedprograms=NULL);

//--------------------------------------------------------

interface IWorkQueueItem: extends IInterface
{
    virtual void execute()=0;
};

interface IWorkQueueThread: extends IInterface
{
    virtual void post(IWorkQueueItem *item)=0;  // takes ownership of item
    virtual void wait()=0;
    virtual unsigned pending()=0;
};

// Simple lightweight async worker queue
// internally thread persists for specified time waiting before self destroying
extern jlib_decl IWorkQueueThread *createWorkQueueThread(unsigned persisttime=1000*60);


#endif