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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS --
4 -- --
5 -- S Y S T E M . O S _ I N T E R F A C E --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1991-1994, Florida State University --
10 -- Copyright (C) 1995-2020, Free Software Foundation, Inc. --
11 -- --
12 -- GNAT is free software; you can redistribute it and/or modify it under --
13 -- terms of the GNU General Public License as published by the Free Soft- --
14 -- ware Foundation; either version 3, or (at your option) any later ver- --
15 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
16 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
17 -- or FITNESS FOR A PARTICULAR PURPOSE. --
18 -- --
19 -- As a special exception under Section 7 of GPL version 3, you are granted --
20 -- additional permissions described in the GCC Runtime Library Exception, --
21 -- version 3.1, as published by the Free Software Foundation. --
22 -- --
23 -- You should have received a copy of the GNU General Public License and --
24 -- a copy of the GCC Runtime Library Exception along with this program; --
25 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
26 -- <http://www.gnu.org/licenses/>. --
27 -- --
28 -- GNARL was developed by the GNARL team at Florida State University. It is --
29 -- now maintained by Ada Core Technologies Inc. in cooperation with Florida --
30 -- State University (http://www.gnat.com). --
31 -- --
32 ------------------------------------------------------------------------------
33
34 -- This is the DragonFly BSD PTHREADS version of this package
35
36 -- This package encapsulates all direct interfaces to OS services
37 -- that are needed by the tasking run-time (libgnarl).
38
39 -- PLEASE DO NOT add any with-clauses to this package or remove the pragma
40 -- Preelaborate. This package is designed to be a bottom-level (leaf) package.
41
42 with Ada.Unchecked_Conversion;
43
44 with Interfaces.C;
45
46 package System.OS_Interface is
47 pragma Preelaborate;
48
49 pragma Linker_Options ("-pthread");
50
51 subtype int is Interfaces.C.int;
52 subtype short is Interfaces.C.short;
53 subtype long is Interfaces.C.long;
54 subtype unsigned is Interfaces.C.unsigned;
55 subtype unsigned_short is Interfaces.C.unsigned_short;
56 subtype unsigned_long is Interfaces.C.unsigned_long;
57 subtype unsigned_char is Interfaces.C.unsigned_char;
58 subtype plain_char is Interfaces.C.plain_char;
59 subtype size_t is Interfaces.C.size_t;
60
61 -----------
62 -- Errno --
63 -----------
64
65 function Errno return int;
66 pragma Inline (Errno);
67
68 EAGAIN : constant := 35;
69 EINTR : constant := 4;
70 EINVAL : constant := 22;
71 ENOMEM : constant := 12;
72 ETIMEDOUT : constant := 60;
73
74 -------------
75 -- Signals --
76 -------------
77
78 Max_Interrupt : constant := 31;
79 type Signal is new int range 0 .. Max_Interrupt;
80 for Signal'Size use int'Size;
81
82 SIGHUP : constant := 1; -- hangup
83 SIGINT : constant := 2; -- interrupt (rubout)
84 SIGQUIT : constant := 3; -- quit (ASCD FS)
85 SIGILL : constant := 4; -- illegal instruction (not reset)
86 SIGTRAP : constant := 5; -- trace trap (not reset)
87 SIGIOT : constant := 6; -- IOT instruction
88 SIGABRT : constant := 6; -- used by abort, replace SIGIOT in the future
89 SIGEMT : constant := 7; -- EMT instruction
90 SIGFPE : constant := 8; -- floating point exception
91 SIGKILL : constant := 9; -- kill (cannot be caught or ignored)
92 SIGBUS : constant := 10; -- bus error
93 SIGSEGV : constant := 11; -- segmentation violation
94 SIGSYS : constant := 12; -- bad argument to system call
95 SIGPIPE : constant := 13; -- write on a pipe with no one to read it
96 SIGALRM : constant := 14; -- alarm clock
97 SIGTERM : constant := 15; -- software termination signal from kill
98 SIGURG : constant := 16; -- urgent condition on IO channel
99 SIGSTOP : constant := 17; -- stop (cannot be caught or ignored)
100 SIGTSTP : constant := 18; -- user stop requested from tty
101 SIGCONT : constant := 19; -- stopped process has been continued
102 SIGCLD : constant := 20; -- alias for SIGCHLD
103 SIGCHLD : constant := 20; -- child status change
104 SIGTTIN : constant := 21; -- background tty read attempted
105 SIGTTOU : constant := 22; -- background tty write attempted
106 SIGIO : constant := 23; -- I/O possible (Solaris SIGPOLL alias)
107 SIGXCPU : constant := 24; -- CPU time limit exceeded
108 SIGXFSZ : constant := 25; -- filesize limit exceeded
109 SIGVTALRM : constant := 26; -- virtual timer expired
110 SIGPROF : constant := 27; -- profiling timer expired
111 SIGWINCH : constant := 28; -- window size change
112 SIGINFO : constant := 29; -- information request (BSD)
113 SIGUSR1 : constant := 30; -- user defined signal 1
114 SIGUSR2 : constant := 31; -- user defined signal 2
115
116 SIGADAABORT : constant := SIGABRT;
117 -- Change this if you want to use another signal for task abort.
118 -- SIGTERM might be a good one.
119
120 type Signal_Set is array (Natural range <>) of Signal;
121
122 -- Interrupts that must be unmasked at all times. DragonFlyBSD
123 -- pthreads will not allow an application to mask out any
124 -- interrupt needed by the threads library.
125 Unmasked : constant Signal_Set :=
126 (SIGTRAP, SIGBUS, SIGTTIN, SIGTTOU, SIGTSTP);
127
128 -- DragonFlyBSD will uses SIGPROF for timing. Do not allow a
129 -- handler to attach to this signal.
130 Reserved : constant Signal_Set := (0 .. 0 => SIGPROF);
131
132 type sigset_t is private;
133
134 function sigaddset
135 (set : access sigset_t;
136 sig : Signal) return int;
137 pragma Import (C, sigaddset, "sigaddset");
138
139 function sigdelset
140 (set : access sigset_t;
141 sig : Signal) return int;
142 pragma Import (C, sigdelset, "sigdelset");
143
144 function sigfillset (set : access sigset_t) return int;
145 pragma Import (C, sigfillset, "sigfillset");
146
147 function sigismember
148 (set : access sigset_t;
149 sig : Signal) return int;
150 pragma Import (C, sigismember, "sigismember");
151
152 function sigemptyset (set : access sigset_t) return int;
153 pragma Import (C, sigemptyset, "sigemptyset");
154
155 -- sigcontext is architecture dependent, so define it private
156 type struct_sigcontext is private;
157
158 type old_struct_sigaction is record
159 sa_handler : System.Address;
160 sa_mask : sigset_t;
161 sa_flags : int;
162 end record;
163 pragma Convention (C, old_struct_sigaction);
164
165 type new_struct_sigaction is record
166 sa_handler : System.Address;
167 sa_flags : int;
168 sa_mask : sigset_t;
169 end record;
170 pragma Convention (C, new_struct_sigaction);
171
172 subtype struct_sigaction is new_struct_sigaction;
173 type struct_sigaction_ptr is access all struct_sigaction;
174
175 SIG_BLOCK : constant := 1;
176 SIG_UNBLOCK : constant := 2;
177 SIG_SETMASK : constant := 3;
178
179 SIG_DFL : constant := 0;
180 SIG_IGN : constant := 1;
181
182 SA_SIGINFO : constant := 16#0040#;
183 SA_ONSTACK : constant := 16#0001#;
184
185 function sigaction
186 (sig : Signal;
187 act : struct_sigaction_ptr;
188 oact : struct_sigaction_ptr) return int;
189 pragma Import (C, sigaction, "sigaction");
190
191 ----------
192 -- Time --
193 ----------
194
195 Time_Slice_Supported : constant Boolean := True;
196 -- Indicates whether time slicing is supported (i.e SCHED_RR is supported)
197
198 type timespec is private;
199
200 function nanosleep (rqtp, rmtp : access timespec) return int;
201 pragma Import (C, nanosleep, "nanosleep");
202
203 type clockid_t is new unsigned_long;
204
205 function clock_getres
206 (clock_id : clockid_t;
207 res : access timespec) return int;
208 pragma Import (C, clock_getres, "clock_getres");
209
210 function clock_gettime
211 (clock_id : clockid_t;
212 tp : access timespec)
213 return int;
214 pragma Import (C, clock_gettime, "clock_gettime");
215
216 function To_Duration (TS : timespec) return Duration;
217 pragma Inline (To_Duration);
218
219 function To_Timespec (D : Duration) return timespec;
220 pragma Inline (To_Timespec);
221
222 type struct_timezone is record
223 tz_minuteswest : int;
224 tz_dsttime : int;
225 end record;
226 pragma Convention (C, struct_timezone);
227
228 procedure usleep (useconds : unsigned_long);
229 pragma Import (C, usleep, "usleep");
230
231 -------------------------
232 -- Priority Scheduling --
233 -------------------------
234
235 SCHED_FIFO : constant := 1;
236 SCHED_OTHER : constant := 2;
237 SCHED_RR : constant := 3;
238
239 function To_Target_Priority
240 (Prio : System.Any_Priority) return Interfaces.C.int;
241 -- Maps System.Any_Priority to a POSIX priority
242
243 -------------
244 -- Process --
245 -------------
246
247 type pid_t is private;
248
249 function kill (pid : pid_t; sig : Signal) return int;
250 pragma Import (C, kill, "kill");
251
252 function getpid return pid_t;
253 pragma Import (C, getpid, "getpid");
254
255 ---------
256 -- LWP --
257 ---------
258
259 function lwp_self return System.Address;
260 -- lwp_self does not exist on this thread library, revert to pthread_self
261 -- which is the closest approximation (with getpid). This function is
262 -- needed to share 7staprop.adb across POSIX-like targets.
263 pragma Import (C, lwp_self, "pthread_self");
264
265 -------------
266 -- Threads --
267 -------------
268
269 type Thread_Body is access
270 function (arg : System.Address) return System.Address;
271 pragma Convention (C, Thread_Body);
272
273 function Thread_Body_Access is new
274 Ada.Unchecked_Conversion (System.Address, Thread_Body);
275
276 type pthread_t is private;
277 subtype Thread_Id is pthread_t;
278
279 type pthread_mutex_t is limited private;
280 type pthread_cond_t is limited private;
281 type pthread_attr_t is limited private;
282 type pthread_mutexattr_t is limited private;
283 type pthread_condattr_t is limited private;
284 type pthread_key_t is private;
285
286 PTHREAD_CREATE_DETACHED : constant := 1;
287 PTHREAD_CREATE_JOINABLE : constant := 0;
288
289 PTHREAD_SCOPE_PROCESS : constant := 0;
290 PTHREAD_SCOPE_SYSTEM : constant := 2;
291
292 -- Read/Write lock not supported on DragonFly. To add support both types
293 -- pthread_rwlock_t and pthread_rwlockattr_t must properly be defined
294 -- with the associated routines pthread_rwlock_[init/destroy] and
295 -- pthread_rwlock_[rdlock/wrlock/unlock].
296
297 subtype pthread_rwlock_t is pthread_mutex_t;
298 subtype pthread_rwlockattr_t is pthread_mutexattr_t;
299
300 -----------
301 -- Stack --
302 -----------
303
304 type stack_t is record
305 ss_sp : System.Address;
306 ss_size : size_t;
307 ss_flags : int;
308 end record;
309 pragma Convention (C, stack_t);
310
311 function sigaltstack
312 (ss : not null access stack_t;
313 oss : access stack_t) return int;
314 pragma Import (C, sigaltstack, "sigaltstack");
315
316 Alternate_Stack : aliased System.Address;
317 -- This is a dummy definition, never used (Alternate_Stack_Size is null)
318
319 Alternate_Stack_Size : constant := 0;
320 -- No alternate signal stack is used on this platform
321
322 Stack_Base_Available : constant Boolean := False;
323 -- Indicates whether the stack base is available on this target. This
324 -- allows us to share s-osinte.adb between all the FSU run time. Note that
325 -- this value can only be true if pthread_t has a complete definition that
326 -- corresponds exactly to the C header files.
327
328 function Get_Stack_Base (thread : pthread_t) return Address;
329 pragma Inline (Get_Stack_Base);
330 -- returns the stack base of the specified thread. Only call this function
331 -- when Stack_Base_Available is True.
332
333 function Get_Page_Size return int;
334 pragma Import (C, Get_Page_Size, "getpagesize");
335 -- Returns the size of a page
336
337 PROT_NONE : constant := 0;
338 PROT_READ : constant := 1;
339 PROT_WRITE : constant := 2;
340 PROT_EXEC : constant := 4;
341 PROT_ALL : constant := PROT_READ + PROT_WRITE + PROT_EXEC;
342 PROT_ON : constant := PROT_NONE;
343 PROT_OFF : constant := PROT_ALL;
344
345 function mprotect (addr : Address; len : size_t; prot : int) return int;
346 pragma Import (C, mprotect);
347
348 ---------------------------------------
349 -- Nonstandard Thread Initialization --
350 ---------------------------------------
351
352 -- FSU_THREADS requires pthread_init, which is nonstandard and this should
353 -- be invoked during the elaboration of s-taprop.adb.
354
355 -- DragonFlyBSD does not require this so we provide an empty Ada body
356
357 procedure pthread_init;
358
359 -------------------------
360 -- POSIX.1c Section 3 --
361 -------------------------
362
363 function sigwait
364 (set : access sigset_t;
365 sig : access Signal) return int;
366 pragma Import (C, sigwait, "sigwait");
367
368 function pthread_kill
369 (thread : pthread_t;
370 sig : Signal) return int;
371 pragma Import (C, pthread_kill, "pthread_kill");
372
373 function pthread_sigmask
374 (how : int;
375 set : access sigset_t;
376 oset : access sigset_t) return int;
377 pragma Import (C, pthread_sigmask, "pthread_sigmask");
378
379 --------------------------
380 -- POSIX.1c Section 11 --
381 --------------------------
382
383 function pthread_mutexattr_init
384 (attr : access pthread_mutexattr_t) return int;
385 pragma Import (C, pthread_mutexattr_init, "pthread_mutexattr_init");
386
387 function pthread_mutexattr_destroy
388 (attr : access pthread_mutexattr_t) return int;
389 pragma Import (C, pthread_mutexattr_destroy, "pthread_mutexattr_destroy");
390
391 function pthread_mutex_init
392 (mutex : access pthread_mutex_t;
393 attr : access pthread_mutexattr_t) return int;
394 pragma Import (C, pthread_mutex_init, "pthread_mutex_init");
395
396 function pthread_mutex_destroy (mutex : access pthread_mutex_t) return int;
397 pragma Import (C, pthread_mutex_destroy, "pthread_mutex_destroy");
398
399 function pthread_mutex_lock (mutex : access pthread_mutex_t) return int;
400 pragma Import (C, pthread_mutex_lock, "pthread_mutex_lock");
401
402 function pthread_mutex_unlock (mutex : access pthread_mutex_t) return int;
403 pragma Import (C, pthread_mutex_unlock, "pthread_mutex_unlock");
404
405 function pthread_condattr_init
406 (attr : access pthread_condattr_t) return int;
407 pragma Import (C, pthread_condattr_init, "pthread_condattr_init");
408
409 function pthread_condattr_destroy
410 (attr : access pthread_condattr_t) return int;
411 pragma Import (C, pthread_condattr_destroy, "pthread_condattr_destroy");
412
413 function pthread_cond_init
414 (cond : access pthread_cond_t;
415 attr : access pthread_condattr_t) return int;
416 pragma Import (C, pthread_cond_init, "pthread_cond_init");
417
418 function pthread_cond_destroy (cond : access pthread_cond_t) return int;
419 pragma Import (C, pthread_cond_destroy, "pthread_cond_destroy");
420
421 function pthread_cond_signal (cond : access pthread_cond_t) return int;
422 pragma Import (C, pthread_cond_signal, "pthread_cond_signal");
423
424 function pthread_cond_wait
425 (cond : access pthread_cond_t;
426 mutex : access pthread_mutex_t) return int;
427 pragma Import (C, pthread_cond_wait, "pthread_cond_wait");
428
429 function pthread_cond_timedwait
430 (cond : access pthread_cond_t;
431 mutex : access pthread_mutex_t;
432 abstime : access timespec) return int;
433 pragma Import (C, pthread_cond_timedwait, "pthread_cond_timedwait");
434
435 Relative_Timed_Wait : constant Boolean := False;
436 -- pthread_cond_timedwait requires an absolute delay time
437
438 --------------------------
439 -- POSIX.1c Section 13 --
440 --------------------------
441
442 PTHREAD_PRIO_NONE : constant := 0;
443 PTHREAD_PRIO_PROTECT : constant := 2;
444 PTHREAD_PRIO_INHERIT : constant := 1;
445
446 function pthread_mutexattr_setprotocol
447 (attr : access pthread_mutexattr_t;
448 protocol : int) return int;
449 pragma Import
450 (C, pthread_mutexattr_setprotocol, "pthread_mutexattr_setprotocol");
451
452 function pthread_mutexattr_getprotocol
453 (attr : access pthread_mutexattr_t;
454 protocol : access int) return int;
455 pragma Import
456 (C, pthread_mutexattr_getprotocol, "pthread_mutexattr_getprotocol");
457
458 function pthread_mutexattr_setprioceiling
459 (attr : access pthread_mutexattr_t;
460 prioceiling : int) return int;
461 pragma Import
462 (C, pthread_mutexattr_setprioceiling,
463 "pthread_mutexattr_setprioceiling");
464
465 function pthread_mutexattr_getprioceiling
466 (attr : access pthread_mutexattr_t;
467 prioceiling : access int) return int;
468 pragma Import
469 (C, pthread_mutexattr_getprioceiling,
470 "pthread_mutexattr_getprioceiling");
471
472 type struct_sched_param is record
473 sched_priority : int;
474 end record;
475 pragma Convention (C, struct_sched_param);
476
477 function pthread_getschedparam
478 (thread : pthread_t;
479 policy : access int;
480 param : access struct_sched_param) return int;
481 pragma Import (C, pthread_getschedparam, "pthread_getschedparam");
482
483 function pthread_setschedparam
484 (thread : pthread_t;
485 policy : int;
486 param : access struct_sched_param) return int;
487 pragma Import (C, pthread_setschedparam, "pthread_setschedparam");
488
489 function pthread_attr_setscope
490 (attr : access pthread_attr_t;
491 contentionscope : int) return int;
492 pragma Import (C, pthread_attr_setscope, "pthread_attr_setscope");
493
494 function pthread_attr_getscope
495 (attr : access pthread_attr_t;
496 contentionscope : access int) return int;
497 pragma Import (C, pthread_attr_getscope, "pthread_attr_getscope");
498
499 function pthread_attr_setinheritsched
500 (attr : access pthread_attr_t;
501 inheritsched : int) return int;
502 pragma Import
503 (C, pthread_attr_setinheritsched, "pthread_attr_setinheritsched");
504
505 function pthread_attr_getinheritsched
506 (attr : access pthread_attr_t;
507 inheritsched : access int) return int;
508 pragma Import
509 (C, pthread_attr_getinheritsched, "pthread_attr_getinheritsched");
510
511 function pthread_attr_setschedpolicy
512 (attr : access pthread_attr_t;
513 policy : int) return int;
514 pragma Import (C, pthread_attr_setschedpolicy,
515 "pthread_attr_setschedpolicy");
516
517 function pthread_attr_getschedpolicy
518 (attr : access pthread_attr_t;
519 policy : access int) return int;
520 pragma Import (C, pthread_attr_getschedpolicy,
521 "pthread_attr_getschedpolicy");
522
523 function pthread_attr_setschedparam
524 (attr : access pthread_attr_t;
525 sched_param : int) return int;
526 pragma Import (C, pthread_attr_setschedparam, "pthread_attr_setschedparam");
527
528 function pthread_attr_getschedparam
529 (attr : access pthread_attr_t;
530 sched_param : access int) return int;
531 pragma Import (C, pthread_attr_getschedparam, "pthread_attr_getschedparam");
532
533 function sched_yield return int;
534 pragma Import (C, sched_yield, "pthread_yield");
535
536 --------------------------
537 -- P1003.1c Section 16 --
538 --------------------------
539
540 function pthread_attr_init (attributes : access pthread_attr_t) return int;
541 pragma Import (C, pthread_attr_init, "pthread_attr_init");
542
543 function pthread_attr_destroy
544 (attributes : access pthread_attr_t) return int;
545 pragma Import (C, pthread_attr_destroy, "pthread_attr_destroy");
546
547 function pthread_attr_setdetachstate
548 (attr : access pthread_attr_t;
549 detachstate : int) return int;
550 pragma Import
551 (C, pthread_attr_setdetachstate, "pthread_attr_setdetachstate");
552
553 function pthread_attr_getdetachstate
554 (attr : access pthread_attr_t;
555 detachstate : access int) return int;
556 pragma Import
557 (C, pthread_attr_getdetachstate, "pthread_attr_getdetachstate");
558
559 function pthread_attr_getstacksize
560 (attr : access pthread_attr_t;
561 stacksize : access size_t) return int;
562 pragma Import
563 (C, pthread_attr_getstacksize, "pthread_attr_getstacksize");
564
565 function pthread_attr_setstacksize
566 (attr : access pthread_attr_t;
567 stacksize : size_t) return int;
568 pragma Import
569 (C, pthread_attr_setstacksize, "pthread_attr_setstacksize");
570
571 function pthread_create
572 (thread : access pthread_t;
573 attributes : access pthread_attr_t;
574 start_routine : Thread_Body;
575 arg : System.Address) return int;
576 pragma Import (C, pthread_create, "pthread_create");
577
578 function pthread_detach (thread : pthread_t) return int;
579 pragma Import (C, pthread_detach, "pthread_detach");
580
581 procedure pthread_exit (status : System.Address);
582 pragma Import (C, pthread_exit, "pthread_exit");
583
584 function pthread_self return pthread_t;
585 pragma Import (C, pthread_self, "pthread_self");
586
587 --------------------------
588 -- POSIX.1c Section 17 --
589 --------------------------
590
591 function pthread_setspecific
592 (key : pthread_key_t;
593 value : System.Address) return int;
594 pragma Import (C, pthread_setspecific, "pthread_setspecific");
595
596 function pthread_getspecific (key : pthread_key_t) return System.Address;
597 pragma Import (C, pthread_getspecific, "pthread_getspecific");
598
599 type destructor_pointer is access procedure (arg : System.Address);
600 pragma Convention (C, destructor_pointer);
601
602 function pthread_key_create
603 (key : access pthread_key_t;
604 destructor : destructor_pointer) return int;
605 pragma Import (C, pthread_key_create, "pthread_key_create");
606
607 ------------------------------------
608 -- Non-portable Pthread Functions --
609 ------------------------------------
610
611 function pthread_set_name_np
612 (thread : pthread_t;
613 name : System.Address) return int;
614 pragma Import (C, pthread_set_name_np, "pthread_set_name_np");
615
616 private
617
618 type sigset_t is array (1 .. 4) of unsigned;
619
620 -- In DragonFlyBSD the component sa_handler turns out to
621 -- be one a union type, and the selector is a macro:
622 -- #define sa_handler __sigaction_u._handler
623 -- #define sa_sigaction __sigaction_u._sigaction
624
625 -- Should we add a signal_context type here ???
626 -- How could it be done independent of the CPU architecture ???
627 -- sigcontext type is opaque, so it is architecturally neutral.
628 -- It is always passed as an access type, so define it as an empty record
629 -- since the contents are not used anywhere.
630
631 type struct_sigcontext is null record;
632 pragma Convention (C, struct_sigcontext);
633
634 type pid_t is new int;
635
636 type time_t is new long;
637
638 type timespec is record
639 ts_sec : time_t;
640 ts_nsec : long;
641 end record;
642 pragma Convention (C, timespec);
643
644 type pthread_t is new System.Address;
645 type pthread_attr_t is new System.Address;
646 type pthread_mutex_t is new System.Address;
647 type pthread_mutexattr_t is new System.Address;
648 type pthread_cond_t is new System.Address;
649 type pthread_condattr_t is new System.Address;
650 type pthread_key_t is new int;
651
652 end System.OS_Interface;