win32/win32thread.h

   1 #ifndef _WIN32THREAD_H
   2 #define _WIN32THREAD_H
   3 typedef struct win32_cond { LONG waiters; HANDLE sem; } perl_cond;
   4 typedef DWORD perl_key;
   5 typedef HANDLE perl_os_thread;
   6
   7 #ifndef DONT_USE_CRITICAL_SECTION
   8
   9 /* Critical Sections used instead of mutexes: lightweight,
  10  * but can't be communicated to child processes, and can't get
  11  * HANDLE to it for use elsewhere.
  12  */
  13 typedef CRITICAL_SECTION perl_mutex;
  14 #define MUTEX_INIT(m) InitializeCriticalSection(m)
  15 #define MUTEX_LOCK(m) EnterCriticalSection(m)
  16 #define MUTEX_UNLOCK(m) LeaveCriticalSection(m)
  17 #define MUTEX_DESTROY(m) DeleteCriticalSection(m)
  18
  19 #else
  20
  21 typedef HANDLE perl_mutex;
  22 #define MUTEX_INIT(m) \
  23     STMT_START {                                                \
  24         if ((*(m) = CreateMutex(NULL,FALSE,NULL)) == NULL)      \
  25             croak("panic: MUTEX_INIT");                         \
  26     } STMT_END
  27 #define MUTEX_LOCK(m) \
  28     STMT_START {                                                \
  29         if (WaitForSingleObject(*(m),INFINITE) == WAIT_FAILED)  \
  30             croak("panic: MUTEX_LOCK");                         \
  31     } STMT_END
  32 #define MUTEX_UNLOCK(m) \
  33     STMT_START {                                                \
  34         if (ReleaseMutex(*(m)) == 0)                            \
  35             croak("panic: MUTEX_UNLOCK");                       \
  36     } STMT_END
  37 #define MUTEX_DESTROY(m) \
  38     STMT_START {                                                \
  39         if (CloseHandle(*(m)) == 0)                             \
  40             croak("panic: MUTEX_DESTROY");                      \
  41     } STMT_END
  42
  43 #endif
  44
  45 /* These macros assume that the mutex associated with the condition
  46  * will always be held before COND_{SIGNAL,BROADCAST,WAIT,DESTROY},
  47  * so there's no separate mutex protecting access to (c)->waiters
  48  */
  49 #define COND_INIT(c) \
  50     STMT_START {                                                \
  51         (c)->waiters = 0;                                       \
  52         (c)->sem = CreateSemaphore(NULL,0,LONG_MAX,NULL);       \
  53         if ((c)->sem == NULL)                                   \
  54             croak("panic: COND_INIT (%ld)",GetLastError());     \
  55     } STMT_END
  56
  57 #define COND_SIGNAL(c) \
  58     STMT_START {                                                \
  59         if ((c)->waiters > 0 &&                                 \
  60             ReleaseSemaphore((c)->sem,1,NULL) == 0)             \
  61             croak("panic: COND_SIGNAL (%ld)",GetLastError());   \
  62     } STMT_END
  63
  64 #define COND_BROADCAST(c) \
  65     STMT_START {                                                \
  66         if ((c)->waiters > 0 &&                                 \
  67             ReleaseSemaphore((c)->sem,(c)->waiters,NULL) == 0)  \
  68             croak("panic: COND_BROADCAST (%ld)",GetLastError());\
  69     } STMT_END
  70
  71 #define COND_WAIT(c, m) \
  72     STMT_START {                                                \
  73         (c)->waiters++;                                         \
  74         MUTEX_UNLOCK(m);                                        \
  75         /* Note that there's no race here, since a              \
  76          * COND_BROADCAST() on another thread will have seen the\
  77          * right number of waiters (i.e. including this one) */ \
  78         if (WaitForSingleObject((c)->sem,INFINITE)==WAIT_FAILED)\
  79             croak("panic: COND_WAIT (%ld)",GetLastError());     \
  80         /* XXX there may be an inconsequential race here */     \
  81         MUTEX_LOCK(m);                                          \
  82         (c)->waiters--;                                         \
  83     } STMT_END
  84
  85 #define COND_DESTROY(c) \
  86     STMT_START {                                                \
  87         (c)->waiters = 0;                                       \
  88         if (CloseHandle((c)->sem) == 0)                         \
  89             croak("panic: COND_DESTROY (%ld)",GetLastError());  \
  90     } STMT_END
  91
  92 #define DETACH(t) \
  93     STMT_START {                                                \
  94         if (CloseHandle((t)->self) == 0) {                      \
  95             MUTEX_UNLOCK(&(t)->mutex);                          \
  96             croak("panic: DETACH");                             \
  97         }                                                       \
  98     } STMT_END
  99
 100
 101 #define THREAD_CREATE(t, f)     Perl_thread_create(t, f)
 102 #define THREAD_POST_CREATE(t)   NOOP
 103
 104 /* XXX Docs mention that the RTL versions of thread creation routines
 105  * should be used, but that advice only seems applicable when the RTL
 106  * is not in a DLL.  RTL DLLs in both Borland and VC seem to do all of
 107  * the init/deinit required upon DLL_THREAD_ATTACH/DETACH.  So we seem
 108  * to be completely safe using straight Win32 API calls, rather than
 109  * the much braindamaged RTL calls.
 110  *
 111  * _beginthread() in the RTLs call CloseHandle() just after the thread
 112  * function returns, which means: 1) we have a race on our hands
 113  * 2) it is impossible to implement join() semantics.
 114  *
 115  * IOW, do *NOT* turn on USE_RTL_THREAD_API!  It is here
 116  * for experimental purposes only. GSAR 98-01-02
 117  */
 118 #ifdef USE_RTL_THREAD_API
 119 #  include <process.h>
 120 #  if defined(__BORLANDC__)
 121      /* Borland RTL doesn't allow a return value from thread function! */
 122 #    define THREAD_RET_TYPE     void _USERENTRY
 123 #    define THREAD_RET_CAST(p)  ((void)(thr->i.retv = (void *)(p)))
 124 #  elif defined (_MSC_VER)
 125 #    define THREAD_RET_TYPE     unsigned __stdcall
 126 #    define THREAD_RET_CAST(p)  ((unsigned)(p))
 127 #  else
 128      /* CRTDLL.DLL doesn't allow a return value from thread function! */
 129 #    define THREAD_RET_TYPE     void __cdecl
 130 #    define THREAD_RET_CAST(p)  ((void)(thr->i.retv = (void *)(p)))
 131 #  endif
 132 #else   /* !USE_RTL_THREAD_API */
 133 #  define THREAD_RET_TYPE       DWORD WINAPI
 134 #  define THREAD_RET_CAST(p)    ((DWORD)(p))
 135 #endif  /* !USE_RTL_THREAD_API */
 136
 137 typedef THREAD_RET_TYPE thread_func_t(void *);
 138
 139
 140 START_EXTERN_C
 141
 142 #if defined(PERLDLL) && defined(USE_DECLSPEC_THREAD) && (!defined(__BORLANDC__) || defined(_DLL))
 143 extern __declspec(thread) struct perl_thread *Perl_current_thread;
 144 #define SET_THR(t)              (Perl_current_thread = t)
 145 #define THR                     Perl_current_thread
 146 #else
 147 #define THR                     Perl_getTHR()
 148 #define SET_THR(t)              Perl_setTHR(t)
 149 #endif
 150 struct perl_thread;
 151
 152 void Perl_alloc_thread_key _((void));
 153 int Perl_thread_create _((struct perl_thread *thr, thread_func_t *fn));
 154 void Perl_set_thread_self _((struct perl_thread *thr));
 155 struct perl_thread *Perl_getTHR _((void));
 156 void Perl_setTHR _((struct perl_thread *t));
 157 void Perl_init_thread_intern _((struct perl_thread *t));
 158
 159 END_EXTERN_C
 160
 161 #define INIT_THREADS NOOP
 162 #define ALLOC_THREAD_KEY Perl_alloc_thread_key()
 163 #define SET_THREAD_SELF(thr) Perl_set_thread_self(thr)
 164
 165 #if defined(USE_RTL_THREAD_API) && !defined(_MSC_VER)
 166 #define JOIN(t, avp)                                                    \
 167     STMT_START {                                                        \
 168         if ((WaitForSingleObject((t)->self,INFINITE) == WAIT_FAILED)    \
 169              || (GetExitCodeThread((t)->self,(LPDWORD)(avp)) == 0)      \
 170              || (CloseHandle((t)->self) == 0))                          \
 171             croak("panic: JOIN");                                       \
 172         *avp = (AV *)((t)->i.retv);                                     \
 173     } STMT_END
 174 #else   /* !USE_RTL_THREAD_API || _MSC_VER */
 175 #define JOIN(t, avp)                                                    \
 176     STMT_START {                                                        \
 177         if ((WaitForSingleObject((t)->self,INFINITE) == WAIT_FAILED)    \
 178              || (GetExitCodeThread((t)->self,(LPDWORD)(avp)) == 0)      \
 179              || (CloseHandle((t)->self) == 0))                          \
 180             croak("panic: JOIN");                                       \
 181     } STMT_END
 182 #endif  /* !USE_RTL_THREAD_API || _MSC_VER */
 183
 184 #define YIELD                   Sleep(0)
 185
 186 #endif /* _WIN32THREAD_H */
 187