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[gcc]
[official-gcc.git] / gcc / ada / s-osinte-freebsd.ads
blob12854445bd3141bc4f3246c7c1f5f655e539ade4
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) 1995-2016, 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 FreeBSD (POSIX Threads) 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 (NetBSD/FreeBSD)
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. FreeBSD
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 -- FreeBSD 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 int;
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 Self_PID : constant pid_t;
250
251 function kill (pid : pid_t; sig : Signal) return int;
252 pragma Import (C, kill, "kill");
253
254 function getpid return pid_t;
255 pragma Import (C, getpid, "getpid");
256
257 ---------
258 -- LWP --
259 ---------
260
261 function lwp_self return System.Address;
262 -- lwp_self does not exist on this thread library, revert to pthread_self
263 -- which is the closest approximation (with getpid). This function is
264 -- needed to share 7staprop.adb across POSIX-like targets.
265 pragma Import (C, lwp_self, "pthread_self");
266
267 -------------
268 -- Threads --
269 -------------
270
271 type Thread_Body is access
272 function (arg : System.Address) return System.Address;
273 pragma Convention (C, Thread_Body);
274
275 function Thread_Body_Access is new
276 Ada.Unchecked_Conversion (System.Address, Thread_Body);
277
278 type pthread_t is private;
279 subtype Thread_Id is pthread_t;
280
281 type pthread_mutex_t is limited private;
282 type pthread_cond_t is limited private;
283 type pthread_attr_t is limited private;
284 type pthread_mutexattr_t is limited private;
285 type pthread_condattr_t is limited private;
286 type pthread_key_t is private;
287
288 PTHREAD_CREATE_DETACHED : constant := 1;
289 PTHREAD_CREATE_JOINABLE : constant := 0;
290
291 PTHREAD_SCOPE_PROCESS : constant := 0;
292 PTHREAD_SCOPE_SYSTEM : constant := 2;
293
294 -- Read/Write lock not supported on freebsd. To add support both types
295 -- pthread_rwlock_t and pthread_rwlockattr_t must properly be defined
296 -- with the associated routines pthread_rwlock_[init/destroy] and
297 -- pthread_rwlock_[rdlock/wrlock/unlock].
298
299 subtype pthread_rwlock_t is pthread_mutex_t;
300 subtype pthread_rwlockattr_t is pthread_mutexattr_t;
301
302 -----------
303 -- Stack --
304 -----------
305
306 type stack_t is record
307 ss_sp : System.Address;
308 ss_size : size_t;
309 ss_flags : int;
310 end record;
311 pragma Convention (C, stack_t);
312
313 function sigaltstack
314 (ss : not null access stack_t;
315 oss : access stack_t) return int;
316 pragma Import (C, sigaltstack, "sigaltstack");
317
318 Alternate_Stack : aliased System.Address;
319 -- This is a dummy definition, never used (Alternate_Stack_Size is null)
320
321 Alternate_Stack_Size : constant := 0;
322 -- No alternate signal stack is used on this platform
323
324 Stack_Base_Available : constant Boolean := False;
325 -- Indicates whether the stack base is available on this target
326
327 function Get_Stack_Base (thread : pthread_t) return Address;
328 pragma Inline (Get_Stack_Base);
329 -- returns the stack base of the specified thread. Only call this function
330 -- when Stack_Base_Available is True.
331
332 function Get_Page_Size return int;
333 pragma Import (C, Get_Page_Size, "getpagesize");
334 -- Returns the size of a page
335
336 PROT_NONE : constant := 0;
337 PROT_READ : constant := 1;
338 PROT_WRITE : constant := 2;
339 PROT_EXEC : constant := 4;
340 PROT_ALL : constant := PROT_READ + PROT_WRITE + PROT_EXEC;
341 PROT_ON : constant := PROT_NONE;
342 PROT_OFF : constant := PROT_ALL;
343
344 function mprotect (addr : Address; len : size_t; prot : int) return int;
345 pragma Import (C, mprotect);
346
347 ---------------------------------------
348 -- Nonstandard Thread Initialization --
349 ---------------------------------------
350
351 -- FSU_THREADS requires pthread_init, which is nonstandard and this should
352 -- be invoked during the elaboration of s-taprop.adb.
353
354 -- FreeBSD does not require this so we provide an empty Ada body
355
356 procedure pthread_init;
357
358 -------------------------
359 -- POSIX.1c Section 3 --
360 -------------------------
361
362 function sigwait
363 (set : access sigset_t;
364 sig : access Signal) return int;
365 pragma Import (C, sigwait, "sigwait");
366
367 function pthread_kill
368 (thread : pthread_t;
369 sig : Signal) return int;
370 pragma Import (C, pthread_kill, "pthread_kill");
371
372 function pthread_sigmask
373 (how : int;
374 set : access sigset_t;
375 oset : access sigset_t) return int;
376 pragma Import (C, pthread_sigmask, "pthread_sigmask");
377
378 --------------------------
379 -- POSIX.1c Section 11 --
380 --------------------------
381
382 function pthread_mutexattr_init
383 (attr : access pthread_mutexattr_t) return int;
384 pragma Import (C, pthread_mutexattr_init, "pthread_mutexattr_init");
385
386 function pthread_mutexattr_destroy
387 (attr : access pthread_mutexattr_t) return int;
388 pragma Import (C, pthread_mutexattr_destroy, "pthread_mutexattr_destroy");
389
390 function pthread_mutex_init
391 (mutex : access pthread_mutex_t;
392 attr : access pthread_mutexattr_t) return int;
393 pragma Import (C, pthread_mutex_init, "pthread_mutex_init");
394
395 function pthread_mutex_destroy (mutex : access pthread_mutex_t) return int;
396 pragma Import (C, pthread_mutex_destroy, "pthread_mutex_destroy");
397
398 function pthread_mutex_lock (mutex : access pthread_mutex_t) return int;
399 pragma Import (C, pthread_mutex_lock, "pthread_mutex_lock");
400
401 function pthread_mutex_unlock (mutex : access pthread_mutex_t) return int;
402 pragma Import (C, pthread_mutex_unlock, "pthread_mutex_unlock");
403
404 function pthread_condattr_init
405 (attr : access pthread_condattr_t) return int;
406 pragma Import (C, pthread_condattr_init, "pthread_condattr_init");
407
408 function pthread_condattr_destroy
409 (attr : access pthread_condattr_t) return int;
410 pragma Import (C, pthread_condattr_destroy, "pthread_condattr_destroy");
411
412 function pthread_cond_init
413 (cond : access pthread_cond_t;
414 attr : access pthread_condattr_t) return int;
415 pragma Import (C, pthread_cond_init, "pthread_cond_init");
416
417 function pthread_cond_destroy (cond : access pthread_cond_t) return int;
418 pragma Import (C, pthread_cond_destroy, "pthread_cond_destroy");
419
420 function pthread_cond_signal (cond : access pthread_cond_t) return int;
421 pragma Import (C, pthread_cond_signal, "pthread_cond_signal");
422
423 function pthread_cond_wait
424 (cond : access pthread_cond_t;
425 mutex : access pthread_mutex_t) return int;
426 pragma Import (C, pthread_cond_wait, "pthread_cond_wait");
427
428 function pthread_cond_timedwait
429 (cond : access pthread_cond_t;
430 mutex : access pthread_mutex_t;
431 abstime : access timespec) return int;
432 pragma Import (C, pthread_cond_timedwait, "pthread_cond_timedwait");
433
434 Relative_Timed_Wait : constant Boolean := False;
435 -- pthread_cond_timedwait requires an absolute delay time
436
437 --------------------------
438 -- POSIX.1c Section 13 --
439 --------------------------
440
441 PTHREAD_PRIO_NONE : constant := 0;
442 PTHREAD_PRIO_PROTECT : constant := 2;
443 PTHREAD_PRIO_INHERIT : constant := 1;
444
445 function pthread_mutexattr_setprotocol
446 (attr : access pthread_mutexattr_t;
447 protocol : int) return int;
448 pragma Import
449 (C, pthread_mutexattr_setprotocol, "pthread_mutexattr_setprotocol");
450
451 function pthread_mutexattr_getprotocol
452 (attr : access pthread_mutexattr_t;
453 protocol : access int) return int;
454 pragma Import
455 (C, pthread_mutexattr_getprotocol, "pthread_mutexattr_getprotocol");
456
457 function pthread_mutexattr_setprioceiling
458 (attr : access pthread_mutexattr_t;
459 prioceiling : int) return int;
460 pragma Import
461 (C, pthread_mutexattr_setprioceiling,
462 "pthread_mutexattr_setprioceiling");
463
464 function pthread_mutexattr_getprioceiling
465 (attr : access pthread_mutexattr_t;
466 prioceiling : access int) return int;
467 pragma Import
468 (C, pthread_mutexattr_getprioceiling,
469 "pthread_mutexattr_getprioceiling");
470
471 type struct_sched_param is record
472 sched_priority : int;
473 end record;
474 pragma Convention (C, struct_sched_param);
475
476 function pthread_getschedparam
477 (thread : pthread_t;
478 policy : access int;
479 param : access struct_sched_param) return int;
480 pragma Import (C, pthread_getschedparam, "pthread_getschedparam");
481
482 function pthread_setschedparam
483 (thread : pthread_t;
484 policy : int;
485 param : access struct_sched_param) return int;
486 pragma Import (C, pthread_setschedparam, "pthread_setschedparam");
487
488 function pthread_attr_setscope
489 (attr : access pthread_attr_t;
490 contentionscope : int) return int;
491 pragma Import (C, pthread_attr_setscope, "pthread_attr_setscope");
492
493 function pthread_attr_getscope
494 (attr : access pthread_attr_t;
495 contentionscope : access int) return int;
496 pragma Import (C, pthread_attr_getscope, "pthread_attr_getscope");
497
498 function pthread_attr_setinheritsched
499 (attr : access pthread_attr_t;
500 inheritsched : int) return int;
501 pragma Import
502 (C, pthread_attr_setinheritsched, "pthread_attr_setinheritsched");
503
504 function pthread_attr_getinheritsched
505 (attr : access pthread_attr_t;
506 inheritsched : access int) return int;
507 pragma Import
508 (C, pthread_attr_getinheritsched, "pthread_attr_getinheritsched");
509
510 function pthread_attr_setschedpolicy
511 (attr : access pthread_attr_t;
512 policy : int) return int;
513 pragma Import (C, pthread_attr_setschedpolicy,
514 "pthread_attr_setschedpolicy");
515
516 function pthread_attr_getschedpolicy
517 (attr : access pthread_attr_t;
518 policy : access int) return int;
519 pragma Import (C, pthread_attr_getschedpolicy,
520 "pthread_attr_getschedpolicy");
521
522 function pthread_attr_setschedparam
523 (attr : access pthread_attr_t;
524 sched_param : int) return int;
525 pragma Import (C, pthread_attr_setschedparam, "pthread_attr_setschedparam");
526
527 function pthread_attr_getschedparam
528 (attr : access pthread_attr_t;
529 sched_param : access int) return int;
530 pragma Import (C, pthread_attr_getschedparam, "pthread_attr_getschedparam");
531
532 function sched_yield return int;
533 pragma Import (C, sched_yield, "pthread_yield");
534
535 --------------------------
536 -- P1003.1c Section 16 --
537 --------------------------
538
539 function pthread_attr_init (attributes : access pthread_attr_t) return int;
540 pragma Import (C, pthread_attr_init, "pthread_attr_init");
541
542 function pthread_attr_destroy
543 (attributes : access pthread_attr_t) return int;
544 pragma Import (C, pthread_attr_destroy, "pthread_attr_destroy");
545
546 function pthread_attr_setdetachstate
547 (attr : access pthread_attr_t;
548 detachstate : int) return int;
549 pragma Import
550 (C, pthread_attr_setdetachstate, "pthread_attr_setdetachstate");
551
552 function pthread_attr_getdetachstate
553 (attr : access pthread_attr_t;
554 detachstate : access int) return int;
555 pragma Import
556 (C, pthread_attr_getdetachstate, "pthread_attr_getdetachstate");
557
558 function pthread_attr_getstacksize
559 (attr : access pthread_attr_t;
560 stacksize : access size_t) return int;
561 pragma Import
562 (C, pthread_attr_getstacksize, "pthread_attr_getstacksize");
563
564 function pthread_attr_setstacksize
565 (attr : access pthread_attr_t;
566 stacksize : size_t) return int;
567 pragma Import
568 (C, pthread_attr_setstacksize, "pthread_attr_setstacksize");
569
570 function pthread_create
571 (thread : access pthread_t;
572 attributes : access pthread_attr_t;
573 start_routine : Thread_Body;
574 arg : System.Address) return int;
575 pragma Import (C, pthread_create, "pthread_create");
576
577 function pthread_detach (thread : pthread_t) return int;
578 pragma Import (C, pthread_detach, "pthread_detach");
579
580 procedure pthread_exit (status : System.Address);
581 pragma Import (C, pthread_exit, "pthread_exit");
582
583 function pthread_self return pthread_t;
584 pragma Import (C, pthread_self, "pthread_self");
585
586 --------------------------
587 -- POSIX.1c Section 17 --
588 --------------------------
589
590 function pthread_setspecific
591 (key : pthread_key_t;
592 value : System.Address) return int;
593 pragma Import (C, pthread_setspecific, "pthread_setspecific");
594
595 function pthread_getspecific (key : pthread_key_t) return System.Address;
596 pragma Import (C, pthread_getspecific, "pthread_getspecific");
597
598 type destructor_pointer is access procedure (arg : System.Address);
599 pragma Convention (C, destructor_pointer);
600
601 function pthread_key_create
602 (key : access pthread_key_t;
603 destructor : destructor_pointer) return int;
604 pragma Import (C, pthread_key_create, "pthread_key_create");
605
606 ------------------------------------
607 -- Non-portable Pthread Functions --
608 ------------------------------------
609
610 function pthread_set_name_np
611 (thread : pthread_t;
612 name : System.Address) return int;
613 pragma Import (C, pthread_set_name_np, "pthread_set_name_np");
614
615 private
616
617 type sigset_t is array (1 .. 4) of unsigned;
618
619 -- In FreeBSD the component sa_handler turns out to
620 -- be one a union type, and the selector is a macro:
621 -- #define sa_handler __sigaction_u._handler
622 -- #define sa_sigaction __sigaction_u._sigaction
623
624 -- Should we add a signal_context type here ???
625 -- How could it be done independent of the CPU architecture ???
626 -- sigcontext type is opaque, so it is architecturally neutral.
627 -- It is always passed as an access type, so define it as an empty record
628 -- since the contents are not used anywhere.
629
630 type struct_sigcontext is null record;
631 pragma Convention (C, struct_sigcontext);
632
633 type pid_t is new int;
634 Self_PID : constant pid_t := 0;
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;
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