win32/win32thread.h

   1 #ifndef _WIN32THREAD_H
   2 #define _WIN32THREAD_H
   3
   4 #include "win32.h"
   5
   6 typedef struct win32_cond { LONG waiters; HANDLE sem; } perl_cond;
   7 typedef DWORD perl_key;
   8 typedef HANDLE perl_os_thread;
   9
  10 #ifndef DONT_USE_CRITICAL_SECTION
  11
  12 /* Critical Sections used instead of mutexes: lightweight,
  13  * but can't be communicated to child processes, and can't get
  14  * HANDLE to it for use elsewhere.
  15  */
  16 typedef CRITICAL_SECTION perl_mutex;
  17 #define MUTEX_INIT(m) InitializeCriticalSection(m)
  18 #define MUTEX_LOCK(m) EnterCriticalSection(m)
  19 #define MUTEX_UNLOCK(m) LeaveCriticalSection(m)
  20 #define MUTEX_DESTROY(m) DeleteCriticalSection(m)
  21
  22 #else
  23
  24 typedef HANDLE perl_mutex;
  25 #  define MUTEX_INIT(m) \
  26     STMT_START {                                                \
  27         if ((*(m) = CreateMutex(NULL,FALSE,NULL)) == NULL)      \
  28             Perl_croak_nocontext("panic: MUTEX_INIT");          \
  29     } STMT_END
  30
  31 #  define MUTEX_LOCK(m) \
  32     STMT_START {                                                \
  33         if (WaitForSingleObject(*(m),INFINITE) == WAIT_FAILED)  \
  34             Perl_croak_nocontext("panic: MUTEX_LOCK");          \
  35     } STMT_END
  36
  37 #  define MUTEX_UNLOCK(m) \
  38     STMT_START {                                                \
  39         if (ReleaseMutex(*(m)) == 0)                            \
  40             Perl_croak_nocontext("panic: MUTEX_UNLOCK");        \
  41     } STMT_END
  42
  43 #  define MUTEX_DESTROY(m) \
  44     STMT_START {                                                \
  45         if (CloseHandle(*(m)) == 0)                             \
  46             Perl_croak_nocontext("panic: MUTEX_DESTROY");       \
  47     } STMT_END
  48
  49 #endif
  50
  51 /* These macros assume that the mutex associated with the condition
  52  * will always be held before COND_{SIGNAL,BROADCAST,WAIT,DESTROY},
  53  * so there's no separate mutex protecting access to (c)->waiters
  54  */
  55 #define COND_INIT(c) \
  56     STMT_START {                                                \
  57         (c)->waiters = 0;                                       \
  58         (c)->sem = Win_CreateSemaphore(NULL,0,LONG_MAX,NULL);   \
  59         if ((c)->sem == NULL)                                   \
  60             Perl_croak_nocontext("panic: COND_INIT (%ld)",GetLastError());      \
  61     } STMT_END
  62
  63 #define COND_SIGNAL(c) \
  64     STMT_START {                                                \
  65         if ((c)->waiters > 0 &&                                 \
  66             ReleaseSemaphore((c)->sem,1,NULL) == 0)             \
  67             Perl_croak_nocontext("panic: COND_SIGNAL (%ld)",GetLastError());    \
  68     } STMT_END
  69
  70 #define COND_BROADCAST(c) \
  71     STMT_START {                                                \
  72         if ((c)->waiters > 0 &&                                 \
  73             ReleaseSemaphore((c)->sem,(c)->waiters,NULL) == 0)  \
  74             Perl_croak_nocontext("panic: COND_BROADCAST (%ld)",GetLastError());\
  75     } STMT_END
  76
  77 #define COND_WAIT(c, m) \
  78     STMT_START {                                                \
  79         (c)->waiters++;                                         \
  80         MUTEX_UNLOCK(m);                                        \
  81         /* Note that there's no race here, since a              \
  82          * COND_BROADCAST() on another thread will have seen the\
  83          * right number of waiters (i.e. including this one) */ \
  84         if (WaitForSingleObject((c)->sem,INFINITE)==WAIT_FAILED)\
  85             Perl_croak_nocontext("panic: COND_WAIT (%ld)",GetLastError());      \
  86         /* XXX there may be an inconsequential race here */     \
  87         MUTEX_LOCK(m);                                          \
  88         (c)->waiters--;                                         \
  89     } STMT_END
  90
  91 #define COND_DESTROY(c) \
  92     STMT_START {                                                \
  93         (c)->waiters = 0;                                       \
  94         if (CloseHandle((c)->sem) == 0)                         \
  95             Perl_croak_nocontext("panic: COND_DESTROY (%ld)",GetLastError());   \
  96     } STMT_END
  97
  98 #define DETACH(t) \
  99     STMT_START {                                                \
 100         if (CloseHandle((t)->self) == 0) {                      \
 101             MUTEX_UNLOCK(&(t)->mutex);                          \
 102             Perl_croak_nocontext("panic: DETACH");              \
 103         }                                                       \
 104     } STMT_END
 105
 106
 107 #define THREAD_CREATE(t, f)     Perl_thread_create(t, f)
 108 #define THREAD_POST_CREATE(t)   NOOP
 109
 110 /* XXX Docs mention that the RTL versions of thread creation routines
 111  * should be used, but that advice only seems applicable when the RTL
 112  * is not in a DLL.  RTL DLLs seem to do all of the init/deinit required
 113  * upon DLL_THREAD_ATTACH/DETACH.  So we seem to be completely safe using
 114  * straight Win32 API calls, rather than the much braindamaged RTL calls.
 115  *
 116  * _beginthread() in the RTLs call CloseHandle() just after the thread
 117  * function returns, which means: 1) we have a race on our hands
 118  * 2) it is impossible to implement join() semantics.
 119  *
 120  * IOW, do *NOT* turn on USE_RTL_THREAD_API!  It is here
 121  * for experimental purposes only. GSAR 98-01-02
 122  */
 123 #ifdef USE_RTL_THREAD_API
 124 #  include <process.h>
 125 #  if defined (_MSC_VER)
 126 #    define THREAD_RET_TYPE     unsigned __stdcall
 127 #    define THREAD_RET_CAST(p)  ((unsigned)(p))
 128 #  else
 129      /* CRTDLL.DLL doesn't allow a return value from thread function! */
 130 #    define THREAD_RET_TYPE     void __cdecl
 131 #    define THREAD_RET_CAST(p)  ((void)(thr->i.retv = (void *)(p)))
 132 #  endif
 133 #else   /* !USE_RTL_THREAD_API */
 134 #  define THREAD_RET_TYPE       DWORD WINAPI
 135 #  define THREAD_RET_CAST(p)    ((DWORD)(p))
 136 #endif  /* !USE_RTL_THREAD_API */
 137
 138 typedef THREAD_RET_TYPE thread_func_t(void *);
 139
 140
 141 START_EXTERN_C
 142
 143 #if defined(PERLDLL) && defined(USE_DECLSPEC_THREAD)
 144 extern __declspec(thread) void *PL_current_context;
 145 #define PERL_SET_CONTEXT(t)             (PL_current_context = t)
 146 #define PERL_GET_CONTEXT                PL_current_context
 147 #else
 148 #define PERL_GET_CONTEXT                Perl_get_context()
 149 #define PERL_SET_CONTEXT(t)             Perl_set_context(t)
 150 #endif
 151
 152 END_EXTERN_C
 153
 154 #define INIT_THREADS            NOOP
 155 #define ALLOC_THREAD_KEY \
 156     STMT_START {                                                        \
 157         if ((PL_thr_key = TlsAlloc()) == TLS_OUT_OF_INDEXES) {          \
 158             PerlIO_printf(PerlIO_stderr(),"panic: TlsAlloc");                           \
 159             exit(1);                                                    \
 160         }                                                               \
 161     } STMT_END
 162
 163 #define FREE_THREAD_KEY \
 164     STMT_START {                                                        \
 165         TlsFree(PL_thr_key);                                            \
 166     } STMT_END
 167
 168 #define PTHREAD_ATFORK(prepare,parent,child)    NOOP
 169
 170 #if defined(USE_RTL_THREAD_API) && !defined(_MSC_VER)
 171 #define JOIN(t, avp)                                                    \
 172     STMT_START {                                                        \
 173         if ((WaitForSingleObject((t)->self,INFINITE) == WAIT_FAILED)    \
 174              || (GetExitCodeThread((t)->self,(LPDWORD)(avp)) == 0)      \
 175              || (CloseHandle((t)->self) == 0))                          \
 176             Perl_croak_nocontext("panic: JOIN");                        \
 177         *avp = (AV *)((t)->i.retv);                                     \
 178     } STMT_END
 179 #else   /* !USE_RTL_THREAD_API || _MSC_VER */
 180 #define JOIN(t, avp)                                                    \
 181     STMT_START {                                                        \
 182         if ((WaitForSingleObject((t)->self,INFINITE) == WAIT_FAILED)    \
 183              || (GetExitCodeThread((t)->self,(LPDWORD)(avp)) == 0)      \
 184              || (CloseHandle((t)->self) == 0))                          \
 185             Perl_croak_nocontext("panic: JOIN");                        \
 186     } STMT_END
 187 #endif  /* !USE_RTL_THREAD_API || _MSC_VER */
 188
 189 #define YIELD                   Sleep(0)
 190
 191 #endif /* _WIN32THREAD_H */
 192