Python/thread_os2.h

   1 /* This code implemented by cvale@netcom.com */
   2
   3 #define INCL_DOSPROCESS
   4 #define INCL_DOSSEMAPHORES
   5 #include "os2.h"
   6 #include "limits.h"
   7
   8 #include "process.h"
   9
  10 #if defined(PYCC_GCC)
  11 #include <sys/builtin.h>
  12 #include <sys/fmutex.h>
  13 #else
  14 long PyThread_get_thread_ident(void);
  15 #endif
  16
  17 /* default thread stack size of 64kB */
  18 #if !defined(THREAD_STACK_SIZE)
  19 #define THREAD_STACK_SIZE       0x10000
  20 #endif
  21
  22 #define OS2_STACKSIZE(x)        (x ? x : THREAD_STACK_SIZE)
  23
  24 /*
  25  * Initialization of the C package, should not be needed.
  26  */
  27 static void
  28 PyThread__init_thread(void)
  29 {
  30 }
  31
  32 /*
  33  * Thread support.
  34  */
  35 long
  36 PyThread_start_new_thread(void (*func)(void *), void *arg)
  37 {
  38     int thread_id;
  39
  40     thread_id = _beginthread(func,
  41                             NULL,
  42                             OS2_STACKSIZE(_pythread_stacksize),
  43                             arg);
  44
  45     if (thread_id == -1) {
  46         dprintf(("_beginthread failed. return %ld\n", errno));
  47     }
  48
  49     return thread_id;
  50 }
  51
  52 long
  53 PyThread_get_thread_ident(void)
  54 {
  55 #if !defined(PYCC_GCC)
  56     PPIB pib;
  57     PTIB tib;
  58 #endif
  59
  60     if (!initialized)
  61         PyThread_init_thread();
  62
  63 #if defined(PYCC_GCC)
  64     return _gettid();
  65 #else
  66     DosGetInfoBlocks(&tib, &pib);
  67     return tib->tib_ptib2->tib2_ultid;
  68 #endif
  69 }
  70
  71 void
  72 PyThread_exit_thread(void)
  73 {
  74     dprintf(("%ld: PyThread_exit_thread called\n",
  75              PyThread_get_thread_ident()));
  76     if (!initialized)
  77         exit(0);
  78     _endthread();
  79 }
  80
  81 /*
  82  * Lock support.  This is implemented with an event semaphore and critical
  83  * sections to make it behave more like a posix mutex than its OS/2
  84  * counterparts.
  85  */
  86
  87 typedef struct os2_lock_t {
  88     int is_set;
  89     HEV changed;
  90 } *type_os2_lock;
  91
  92 PyThread_type_lock
  93 PyThread_allocate_lock(void)
  94 {
  95 #if defined(PYCC_GCC)
  96     _fmutex *sem = malloc(sizeof(_fmutex));
  97     if (!initialized)
  98         PyThread_init_thread();
  99     dprintf(("%ld: PyThread_allocate_lock() -> %lx\n",
 100              PyThread_get_thread_ident(),
 101              (long)sem));
 102     if (_fmutex_create(sem, 0)) {
 103         free(sem);
 104         sem = NULL;
 105     }
 106     return (PyThread_type_lock)sem;
 107 #else
 108     APIRET rc;
 109     type_os2_lock lock = (type_os2_lock)malloc(sizeof(struct os2_lock_t));
 110
 111     dprintf(("PyThread_allocate_lock called\n"));
 112     if (!initialized)
 113         PyThread_init_thread();
 114
 115     lock->is_set = 0;
 116
 117     DosCreateEventSem(NULL, &lock->changed, 0, 0);
 118
 119     dprintf(("%ld: PyThread_allocate_lock() -> %p\n",
 120              PyThread_get_thread_ident(),
 121              lock->changed));
 122
 123     return (PyThread_type_lock)lock;
 124 #endif
 125 }
 126
 127 void
 128 PyThread_free_lock(PyThread_type_lock aLock)
 129 {
 130 #if !defined(PYCC_GCC)
 131     type_os2_lock lock = (type_os2_lock)aLock;
 132 #endif
 133
 134     dprintf(("%ld: PyThread_free_lock(%p) called\n",
 135              PyThread_get_thread_ident(),aLock));
 136
 137 #if defined(PYCC_GCC)
 138     if (aLock) {
 139         _fmutex_close((_fmutex *)aLock);
 140         free((_fmutex *)aLock);
 141     }
 142 #else
 143     DosCloseEventSem(lock->changed);
 144     free(aLock);
 145 #endif
 146 }
 147
 148 /*
 149  * Return 1 on success if the lock was acquired
 150  *
 151  * and 0 if the lock was not acquired.
 152  */
 153 int
 154 PyThread_acquire_lock(PyThread_type_lock aLock, int waitflag)
 155 {
 156 #if !defined(PYCC_GCC)
 157     int   done = 0;
 158     ULONG count;
 159     PID   pid = 0;
 160     TID   tid = 0;
 161     type_os2_lock lock = (type_os2_lock)aLock;
 162 #endif
 163
 164     dprintf(("%ld: PyThread_acquire_lock(%p, %d) called\n",
 165              PyThread_get_thread_ident(),
 166              aLock,
 167              waitflag));
 168
 169 #if defined(PYCC_GCC)
 170     /* always successful if the lock doesn't exist */
 171     if (aLock &&
 172         _fmutex_request((_fmutex *)aLock, waitflag ? 0 : _FMR_NOWAIT))
 173         return 0;
 174 #else
 175     while (!done) {
 176         /* if the lock is currently set, we have to wait for
 177          * the state to change
 178          */
 179         if (lock->is_set) {
 180             if (!waitflag)
 181                 return 0;
 182             DosWaitEventSem(lock->changed, SEM_INDEFINITE_WAIT);
 183         }
 184
 185         /* enter a critical section and try to get the semaphore.  If
 186          * it is still locked, we will try again.
 187          */
 188         if (DosEnterCritSec())
 189             return 0;
 190
 191         if (!lock->is_set) {
 192             lock->is_set = 1;
 193             DosResetEventSem(lock->changed, &count);
 194             done = 1;
 195         }
 196
 197         DosExitCritSec();
 198     }
 199 #endif
 200
 201     return 1;
 202 }
 203
 204 void
 205 PyThread_release_lock(PyThread_type_lock aLock)
 206 {
 207 #if !defined(PYCC_GCC)
 208     type_os2_lock lock = (type_os2_lock)aLock;
 209 #endif
 210
 211     dprintf(("%ld: PyThread_release_lock(%p) called\n",
 212              PyThread_get_thread_ident(),
 213              aLock));
 214
 215 #if defined(PYCC_GCC)
 216     if (aLock)
 217         _fmutex_release((_fmutex *)aLock);
 218 #else
 219     if (!lock->is_set) {
 220         dprintf(("%ld: Could not PyThread_release_lock(%p) error: %l\n",
 221                  PyThread_get_thread_ident(),
 222                  aLock,
 223                  GetLastError()));
 224         return;
 225     }
 226
 227     if (DosEnterCritSec()) {
 228         dprintf(("%ld: Could not PyThread_release_lock(%p) error: %l\n",
 229                  PyThread_get_thread_ident(),
 230                  aLock,
 231                  GetLastError()));
 232         return;
 233     }
 234
 235     lock->is_set = 0;
 236     DosPostEventSem(lock->changed);
 237
 238     DosExitCritSec();
 239 #endif
 240 }
 241
 242 /* minimum/maximum thread stack sizes supported */
 243 #define THREAD_MIN_STACKSIZE    0x8000          /* 32kB */
 244 #define THREAD_MAX_STACKSIZE    0x2000000       /* 32MB */
 245
 246 /* set the thread stack size.
 247  * Return 0 if size is valid, -1 otherwise.
 248  */
 249 static int
 250 _pythread_os2_set_stacksize(size_t size)
 251 {
 252     /* set to default */
 253     if (size == 0) {
 254         _pythread_stacksize = 0;
 255         return 0;
 256     }
 257
 258     /* valid range? */
 259     if (size >= THREAD_MIN_STACKSIZE && size < THREAD_MAX_STACKSIZE) {
 260         _pythread_stacksize = size;
 261         return 0;
 262     }
 263
 264     return -1;
 265 }
 266
 267 #define THREAD_SET_STACKSIZE(x) _pythread_os2_set_stacksize(x)