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
PyThread__init_thread(void)28 PyThread__init_thread(void)
29 {
30 }
31 
32 /*
33  * Thread support.
34  */
35 long
PyThread_start_new_thread(void (* func)(void *),void * arg)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
PyThread_get_thread_ident(void)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
PyThread_exit_thread(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
PyThread_allocate_lock(void)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
PyThread_free_lock(PyThread_type_lock aLock)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
PyThread_acquire_lock(PyThread_type_lock aLock,int waitflag)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
PyThread_release_lock(PyThread_type_lock aLock)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
_pythread_os2_set_stacksize(size_t size)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)
268