gcc/ada/libgnarl/s-osinte__gnu.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                GNU ADA 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) 1995-2024, 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.       --
  29 -- Extensive contributions were provided by Ada Core Technologies, Inc.     --
  30 --                                                                          --
  31 ------------------------------------------------------------------------------
  32
  33 --  This is the GNU/Hurd (POSIX Threads) version of this package
  34
  35 --  This package encapsulates all direct interfaces to OS services
  36 --  that are needed by children of System.
  37
  38 --  PLEASE DO NOT add any with-clauses to this package or remove the pragma
  39 --  Preelaborate. This package is designed to be a bottom-level (leaf) package
  40
  41 with Ada.Unchecked_Conversion;
  42
  43 with Interfaces.C;
  44
  45 with System.OS_Locks;
  46 with System.Parameters;
  47
  48 package System.OS_Interface is
  49    pragma Preelaborate;
  50
  51    pragma Linker_Options ("-lpthread");
  52    pragma Linker_Options ("-lrt");
  53
  54    subtype int            is Interfaces.C.int;
  55    subtype char           is Interfaces.C.char;
  56    subtype short          is Interfaces.C.short;
  57    subtype long           is Interfaces.C.long;
  58    subtype unsigned       is Interfaces.C.unsigned;
  59    subtype unsigned_short is Interfaces.C.unsigned_short;
  60    subtype unsigned_long  is Interfaces.C.unsigned_long;
  61    subtype unsigned_char  is Interfaces.C.unsigned_char;
  62    subtype plain_char     is Interfaces.C.plain_char;
  63    subtype size_t         is Interfaces.C.size_t;
  64
  65    -----------
  66    -- Errno --
  67    -----------
  68    --  From /usr/include/i386-gnu/bits/errno.h
  69
  70    function errno return int;
  71    pragma Import (C, errno, "__get_errno");
  72
  73    EAGAIN   : constant := 1073741859;
  74    EINTR    : constant := 1073741828;
  75    EINVAL   : constant := 1073741846;
  76    ENOMEM   : constant := 1073741836;
  77    EPERM    : constant := 1073741825;
  78    ETIMEDOUT    : constant := 1073741884;
  79
  80    -------------
  81    -- Signals --
  82    -------------
  83    --  From /usr/include/i386-gnu/bits/signum.h
  84
  85    Max_Interrupt : constant := 32;
  86    type Signal is new int range 0 .. Max_Interrupt;
  87    for Signal'Size use int'Size;
  88
  89    SIGHUP     : constant := 1; --  hangup
  90    SIGINT     : constant := 2; --  interrupt (rubout)
  91    SIGQUIT    : constant := 3; --  quit (ASCD FS)
  92    SIGILL     : constant := 4; --  illegal instruction (not reset)
  93    SIGTRAP    : constant := 5; --  trace trap (not reset)
  94    SIGIOT     : constant := 6; --  IOT instruction
  95    SIGABRT    : constant := 6; --  used by abort, replace SIGIOT in the  future
  96    SIGEMT     : constant := 7; --  EMT instruction
  97    SIGFPE     : constant := 8; --  floating point exception
  98    SIGKILL    : constant := 9; --  kill (cannot be caught or ignored)
  99    SIGBUS     : constant := 10; --  bus error
 100    SIGSEGV    : constant := 11; --  segmentation violation
 101    SIGSYS     : constant := 12; --  bad argument to system call
 102    SIGPIPE    : constant := 13; --  write on a pipe with no one to read it
 103    SIGALRM    : constant := 14; --  alarm clock
 104    SIGTERM    : constant := 15; --  software termination signal from kill
 105    SIGURG     : constant := 16; --  urgent condition on IO channel
 106    SIGSTOP    : constant := 17; --  stop (cannot be caught or ignored)
 107    SIGTSTP    : constant := 18; --  user stop requested from tty
 108    SIGCONT    : constant := 19; --  stopped process has been continued
 109    SIGCLD     : constant := 20; --  alias for SIGCHLD
 110    SIGCHLD    : constant := 20; --  child status change
 111    SIGTTIN    : constant := 21; --  background tty read attempted
 112    SIGTTOU    : constant := 22; --  background tty write attempted
 113    SIGIO      : constant := 23; --  I/O possible (Solaris SIGPOLL alias)
 114    SIGPOLL    : constant := 23; --  I/O possible (same as SIGIO?)
 115    SIGXCPU    : constant := 24; --  CPU time limit exceeded
 116    SIGXFSZ    : constant := 25; --  filesize limit exceeded
 117    SIGVTALRM  : constant := 26; --  virtual timer expired
 118    SIGPROF    : constant := 27; --  profiling timer expired
 119    SIGWINCH   : constant := 28; --  window size change
 120    SIGINFO    : constant := 29; --  information request (NetBSD/FreeBSD)
 121    SIGUSR1    : constant := 30; --  user defined signal 1
 122    SIGUSR2    : constant := 31; --  user defined signal 2
 123    SIGLOST    : constant := 32; --  Resource lost (Sun); server died (GNU)
 124
 125    SIGADAABORT : constant := SIGABRT;
 126    --  Change this if you want to use another signal for task abort.
 127    --  SIGTERM might be a good one.
 128
 129    type Signal_Set is array (Natural range <>) of Signal;
 130
 131    Unmasked    : constant Signal_Set := (
 132       SIGTRAP,
 133       --  To enable debugging on multithreaded applications, mark SIGTRAP to
 134       --  be kept unmasked.
 135
 136       SIGBUS,
 137
 138       SIGTTIN, SIGTTOU, SIGTSTP,
 139       --  Keep these three signals unmasked so that background processes
 140       --  and IO behaves as normal "C" applications
 141
 142       SIGPROF,
 143       --  To avoid confusing the profiler
 144
 145       SIGKILL, SIGSTOP);
 146       --  These two signals actually cannot be masked;
 147       --  POSIX simply won't allow it.
 148
 149    Reserved    : constant Signal_Set :=
 150    --  I am not sure why the following signal is reserved.
 151    --  I guess they are not supported by this version of GNU/Hurd.
 152      (0 .. 0 => SIGVTALRM);
 153
 154    type sigset_t is private;
 155
 156    --  From /usr/include/signal.h /usr/include/i386-gnu/bits/sigset.h
 157    function sigaddset (set : access sigset_t; sig : Signal) return int;
 158    pragma Import (C, sigaddset, "sigaddset");
 159
 160    function sigdelset (set : access sigset_t; sig : Signal) return int;
 161    pragma Import (C, sigdelset, "sigdelset");
 162
 163    function sigfillset (set : access sigset_t) return int;
 164    pragma Import (C, sigfillset, "sigfillset");
 165
 166    function sigismember (set : access sigset_t; sig : Signal) return int;
 167    pragma Import (C, sigismember, "sigismember");
 168
 169    function sigemptyset (set : access sigset_t) return int;
 170    pragma Import (C, sigemptyset, "sigemptyset");
 171
 172    --  sigcontext is architecture dependent, so define it private
 173    type struct_sigcontext is private;
 174
 175    --  From /usr/include/i386-gnu/bits/sigaction.h: Note: arg. order differs
 176    type struct_sigaction is record
 177       sa_handler : System.Address;
 178       sa_mask    : sigset_t;
 179       sa_flags   : int;
 180    end record;
 181    pragma Convention (C, struct_sigaction);
 182
 183    type struct_sigaction_ptr is access all struct_sigaction;
 184
 185    --  From /usr/include/i386-gnu/bits/sigaction.h
 186    SIG_BLOCK   : constant := 1;
 187    SIG_UNBLOCK : constant := 2;
 188    SIG_SETMASK : constant := 3;
 189
 190    --  From /usr/include/i386-gnu/bits/signum.h
 191    SIG_ERR  : constant := 1;
 192    SIG_DFL  : constant := 0;
 193    SIG_IGN  : constant := 1;
 194    SIG_HOLD : constant := 2;
 195
 196    --  From /usr/include/i386-gnu/bits/sigaction.h
 197    SA_SIGINFO : constant := 16#0040#;
 198    SA_ONSTACK : constant := 16#0001#;
 199
 200    function sigaction
 201      (sig  : Signal;
 202       act  : struct_sigaction_ptr;
 203       oact : struct_sigaction_ptr) return int;
 204    pragma Import (C, sigaction, "sigaction");
 205
 206    ----------
 207    -- Time --
 208    ----------
 209
 210    Time_Slice_Supported : constant Boolean := True;
 211    --  Indicates whether time slicing is supported (i.e SCHED_RR is supported)
 212
 213    type timespec is private;
 214
 215    function nanosleep (rqtp, rmtp : access timespec) return int;
 216    pragma Import (C, nanosleep, "nanosleep");
 217
 218    type clockid_t is new int;
 219    CLOCK_REALTIME : constant clockid_t := 0;
 220
 221    --  From: /usr/include/time.h
 222    function clock_gettime
 223      (clock_id : clockid_t;
 224       tp       : access timespec)
 225       return int;
 226    pragma Import (C, clock_gettime, "clock_gettime");
 227
 228    function clock_getres
 229      (clock_id : clockid_t;
 230       res      : access timespec) return int;
 231    pragma Import (C, clock_getres, "clock_getres");
 232
 233    function To_Duration (TS : timespec) return Duration;
 234    pragma Inline (To_Duration);
 235
 236    function To_Timespec (D : Duration) return timespec;
 237    pragma Inline (To_Timespec);
 238
 239    --  From: /usr/include/unistd.h
 240    function sysconf (name : int) return long;
 241    pragma Import (C, sysconf);
 242
 243    --  From /usr/include/i386-gnu/bits/confname.h
 244    SC_CLK_TCK          : constant := 2;
 245    SC_NPROCESSORS_ONLN : constant := 84;
 246
 247    -------------------------
 248    -- Priority Scheduling --
 249    -------------------------
 250    --  From /usr/include/i386-gnu/bits/sched.h
 251
 252    SCHED_OTHER : constant := 0;
 253    SCHED_FIFO  : constant := 1;
 254    SCHED_RR    : constant := 2;
 255
 256    function To_Target_Priority
 257      (Prio : System.Any_Priority) return Interfaces.C.int;
 258    --  Maps System.Any_Priority to a POSIX priority.
 259
 260    -------------
 261    -- Process --
 262    -------------
 263
 264    type pid_t is private;
 265
 266    --  From: /usr/include/signal.h
 267    function kill (pid : pid_t; sig : Signal) return int;
 268    pragma Import (C, kill, "kill");
 269
 270    --  From: /usr/include/unistd.h
 271    function getpid return pid_t;
 272    pragma Import (C, getpid, "getpid");
 273
 274    ---------
 275    -- LWP --
 276    ---------
 277
 278    --  From: /usr/include/pthread/pthread.h
 279    function lwp_self return System.Address;
 280    --  lwp_self does not exist on this thread library, revert to pthread_self
 281    --  which is the closest approximation (with getpid). This function is
 282    --  needed to share 7staprop.adb across POSIX-like targets.
 283    pragma Import (C, lwp_self, "pthread_self");
 284
 285    -------------
 286    -- Threads --
 287    -------------
 288
 289    type Thread_Body is access
 290      function (arg : System.Address) return System.Address;
 291    pragma Convention (C, Thread_Body);
 292
 293    function Thread_Body_Access is new
 294      Ada.Unchecked_Conversion (System.Address, Thread_Body);
 295
 296    --  From: /usr/include/bits/pthread.h:typedef int __pthread_t;
 297    --  /usr/include/pthread/pthreadtypes.h:typedef __pthread_t pthread_t;
 298    type pthread_t is new unsigned_long;
 299    subtype Thread_Id        is pthread_t;
 300
 301    function To_pthread_t is new Ada.Unchecked_Conversion
 302      (unsigned_long, pthread_t);
 303
 304    subtype pthread_mutex_t  is System.OS_Locks.pthread_mutex_t;
 305    type pthread_rwlock_t     is limited private;
 306    type pthread_cond_t       is limited private;
 307    type pthread_attr_t       is limited private;
 308    type pthread_mutexattr_t  is limited private;
 309    type pthread_rwlockattr_t is limited private;
 310    type pthread_condattr_t   is limited private;
 311    type pthread_key_t        is private;
 312
 313    --  From /usr/include/pthread/pthreadtypes.h
 314    PTHREAD_CREATE_DETACHED : constant := 1;
 315    PTHREAD_CREATE_JOINABLE : constant := 0;
 316
 317    PTHREAD_SCOPE_PROCESS : constant := 1;
 318    PTHREAD_SCOPE_SYSTEM  : constant := 0;
 319
 320    -----------
 321    -- Stack --
 322    -----------
 323
 324    --  From: /usr/include/i386-gnu/bits/sigstack.h
 325    type stack_t is record
 326       ss_sp    : System.Address;
 327       ss_size  : size_t;
 328       ss_flags : int;
 329    end record;
 330    pragma Convention (C, stack_t);
 331
 332    function sigaltstack
 333      (ss  : not null access stack_t;
 334       oss : access stack_t) return int;
 335    pragma Import (C, sigaltstack, "sigaltstack");
 336
 337    Alternate_Stack : aliased System.Address;
 338    --  This is a dummy definition, never used (Alternate_Stack_Size is null)
 339
 340    Alternate_Stack_Size : constant := 0;
 341    --  No alternate signal stack is used on this platform
 342
 343    Stack_Base_Available : constant Boolean := False;
 344    --  Indicates whether the stack base is available on this target
 345
 346    function Get_Stack_Base (thread : pthread_t) return Address;
 347    pragma Inline (Get_Stack_Base);
 348    --  returns the stack base of the specified thread. Only call this function
 349    --  when Stack_Base_Available is True.
 350
 351    --  From: /usr/include/i386-gnu/bits/shm.h
 352    function Get_Page_Size return int;
 353    pragma Import (C, Get_Page_Size, "getpagesize");
 354    --  Returns the size of a page
 355
 356    --  From /usr/include/i386-gnu/bits/mman.h
 357    PROT_NONE  : constant := 0;
 358    PROT_READ  : constant := 4;
 359    PROT_WRITE : constant := 2;
 360    PROT_EXEC  : constant := 1;
 361    PROT_ALL   : constant := PROT_READ + PROT_WRITE + PROT_EXEC;
 362    PROT_ON    : constant := PROT_NONE;
 363    PROT_OFF   : constant := PROT_ALL;
 364
 365    --  From /usr/include/i386-gnu/bits/mman.h
 366    function mprotect (addr : Address; len : size_t; prot : int) return int;
 367    pragma Import (C, mprotect);
 368
 369    ---------------------------------------
 370    -- Nonstandard Thread Initialization --
 371    ---------------------------------------
 372
 373    procedure pthread_init;
 374    pragma Inline (pthread_init);
 375    --  This is a dummy procedure to share some GNULLI files
 376
 377    -------------------------
 378    -- POSIX.1c  Section 3 --
 379    -------------------------
 380
 381    --  From: /usr/include/signal.h:
 382    --  sigwait (__const sigset_t *__restrict __set, int *__restrict __sig)
 383    function sigwait (set : access sigset_t; sig : access Signal) return int;
 384    pragma Import (C, sigwait, "sigwait");
 385
 386    --  From: /usr/include/pthread/pthread.h:
 387    --  extern int pthread_kill (pthread_t thread, int signo);
 388    function pthread_kill (thread : pthread_t; sig : Signal) return int;
 389    pragma Import (C, pthread_kill, "pthread_kill");
 390
 391    --  From: /usr/include/i386-gnu/bits/sigthread.h
 392    --  extern int pthread_sigmask (int __how, __const __sigset_t *__newmask,
 393    --  __sigset_t *__oldmask) __THROW;
 394    function pthread_sigmask
 395      (how  : int;
 396       set  : access sigset_t;
 397       oset : access sigset_t) return int;
 398    pragma Import (C, pthread_sigmask, "pthread_sigmask");
 399
 400    --------------------------
 401    -- POSIX.1c  Section 11 --
 402    --------------------------
 403
 404    --  From: /usr/include/pthread/pthread.h and
 405    --  /usr/include/pthread/pthreadtypes.h
 406    function pthread_mutexattr_init
 407      (attr : access pthread_mutexattr_t) return int;
 408    pragma Import (C, pthread_mutexattr_init, "pthread_mutexattr_init");
 409
 410    function pthread_mutexattr_destroy
 411      (attr : access pthread_mutexattr_t) return int;
 412    pragma Import (C, pthread_mutexattr_destroy, "pthread_mutexattr_destroy");
 413
 414    function pthread_mutex_init
 415      (mutex : access pthread_mutex_t;
 416       attr  : access pthread_mutexattr_t) return int;
 417    pragma Import (C, pthread_mutex_init, "pthread_mutex_init");
 418
 419    function pthread_mutex_destroy (mutex : access pthread_mutex_t) return int;
 420    pragma Import (C, pthread_mutex_destroy, "pthread_mutex_destroy");
 421
 422    function pthread_mutex_lock (mutex : access pthread_mutex_t) return int;
 423    pragma Import (C, pthread_mutex_lock, "pthread_mutex_lock");
 424
 425    function pthread_mutex_unlock (mutex : access pthread_mutex_t) return int;
 426    pragma Import (C, pthread_mutex_unlock, "pthread_mutex_unlock");
 427
 428    function pthread_rwlockattr_init
 429      (attr : access pthread_rwlockattr_t) return int;
 430    pragma Import (C, pthread_rwlockattr_init, "pthread_rwlockattr_init");
 431
 432    function pthread_rwlockattr_destroy
 433      (attr : access pthread_rwlockattr_t) return int;
 434    pragma Import (C, pthread_rwlockattr_destroy, "pthread_rwlockattr_destroy");
 435    PTHREAD_RWLOCK_PREFER_READER_NP              : constant := 0;
 436    PTHREAD_RWLOCK_PREFER_WRITER_NP              : constant := 1;
 437    PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP : constant := 2;
 438
 439    function pthread_rwlockattr_setkind_np
 440      (attr : access pthread_rwlockattr_t;
 441       pref : int) return int;
 442    pragma Import
 443      (C, pthread_rwlockattr_setkind_np, "pthread_rwlockattr_setkind_np");
 444
 445    function pthread_rwlock_init
 446      (mutex : access pthread_rwlock_t;
 447       attr  : access pthread_rwlockattr_t) return int;
 448    pragma Import (C, pthread_rwlock_init, "pthread_rwlock_init");
 449
 450    function pthread_rwlock_destroy
 451      (mutex : access pthread_rwlock_t) return int;
 452    pragma Import (C, pthread_rwlock_destroy, "pthread_rwlock_destroy");
 453
 454    function pthread_rwlock_rdlock (mutex : access pthread_rwlock_t) return int;
 455    pragma Import (C, pthread_rwlock_rdlock, "pthread_rwlock_rdlock");
 456
 457    function pthread_rwlock_wrlock (mutex : access pthread_rwlock_t) return int;
 458    pragma Import (C, pthread_rwlock_wrlock, "pthread_rwlock_wrlock");
 459
 460    function pthread_rwlock_unlock (mutex : access pthread_rwlock_t) return int;
 461    pragma Import (C, pthread_rwlock_unlock, "pthread_rwlock_unlock");
 462
 463    function pthread_condattr_init
 464      (attr : access pthread_condattr_t) return int;
 465    pragma Import (C, pthread_condattr_init, "pthread_condattr_init");
 466
 467    function pthread_condattr_destroy
 468      (attr : access pthread_condattr_t) return int;
 469    pragma Import (C, pthread_condattr_destroy, "pthread_condattr_destroy");
 470
 471    function pthread_cond_init
 472      (cond : access pthread_cond_t;
 473       attr : access pthread_condattr_t) return int;
 474    pragma Import (C, pthread_cond_init, "pthread_cond_init");
 475
 476    function pthread_cond_destroy (cond : access pthread_cond_t) return int;
 477    pragma Import (C, pthread_cond_destroy, "pthread_cond_destroy");
 478
 479    function pthread_cond_signal (cond : access pthread_cond_t) return int;
 480    pragma Import (C, pthread_cond_signal, "pthread_cond_signal");
 481
 482    function pthread_cond_wait
 483      (cond  : access pthread_cond_t;
 484       mutex : access pthread_mutex_t) return int;
 485    pragma Import (C, pthread_cond_wait, "pthread_cond_wait");
 486
 487    function pthread_cond_timedwait
 488      (cond    : access pthread_cond_t;
 489       mutex   : access pthread_mutex_t;
 490       abstime : access timespec) return int;
 491    pragma Import (C, pthread_cond_timedwait, "pthread_cond_timedwait");
 492
 493    Relative_Timed_Wait : constant Boolean := False;
 494    --  pthread_cond_timedwait requires an absolute delay time
 495
 496    --------------------------
 497    -- POSIX.1c  Section 13 --
 498    --------------------------
 499    --  From /usr/include/pthread/pthreadtypes.h
 500
 501    PTHREAD_PRIO_NONE    : constant := 0;
 502    PTHREAD_PRIO_PROTECT : constant := 2;
 503    PTHREAD_PRIO_INHERIT : constant := 1;
 504
 505    --  GNU/Hurd does not support Thread Priority Protection or Thread
 506    --  Priority Inheritance and lacks some pthread_mutexattr_* functions.
 507    --  Replace them with dummy versions.
 508    --  From: /usr/include/pthread/pthread.h
 509
 510    function pthread_mutexattr_setprotocol
 511      (attr     : access pthread_mutexattr_t;
 512       protocol : int) return int;
 513    pragma Import (C, pthread_mutexattr_setprotocol,
 514      "pthread_mutexattr_setprotocol");
 515
 516    function pthread_mutexattr_getprotocol
 517      (attr     : access pthread_mutexattr_t;
 518       protocol : access int) return int;
 519    pragma Import (C, pthread_mutexattr_getprotocol,
 520      "pthread_mutexattr_getprotocol");
 521
 522    function pthread_mutexattr_setprioceiling
 523      (attr     : access pthread_mutexattr_t;
 524       prioceiling : int) return int;
 525
 526    function pthread_mutexattr_getprioceiling
 527      (attr     : access pthread_mutexattr_t;
 528       prioceiling : access int) return int;
 529
 530    type struct_sched_param is record
 531       sched_priority : int;  --  scheduling priority
 532    end record;
 533    pragma Convention (C, struct_sched_param);
 534
 535    function pthread_setschedparam
 536      (thread : pthread_t;
 537       policy : int;
 538       param  : access struct_sched_param) return int;
 539
 540    function pthread_attr_setscope
 541      (attr            : access pthread_attr_t;
 542       contentionscope : int) return int;
 543    pragma Import (C, pthread_attr_setscope, "pthread_attr_setscope");
 544
 545    function pthread_attr_getscope
 546      (attr            : access pthread_attr_t;
 547       contentionscope : access int) return int;
 548    pragma Import (C, pthread_attr_getscope, "pthread_attr_getscope");
 549
 550    function pthread_attr_setinheritsched
 551      (attr            : access pthread_attr_t;
 552       inheritsched : int) return int;
 553    pragma Import (C, pthread_attr_setinheritsched,
 554      "pthread_attr_setinheritsched");
 555
 556    function pthread_attr_getinheritsched
 557      (attr         : access pthread_attr_t;
 558       inheritsched : access int) return int;
 559    pragma Import (C, pthread_attr_getinheritsched,
 560      "pthread_attr_getinheritsched");
 561
 562    function pthread_attr_setschedpolicy
 563      (attr   : access pthread_attr_t;
 564       policy : int) return int;
 565    pragma Import (C, pthread_attr_setschedpolicy, "pthread_setschedpolicy");
 566
 567    function sched_yield return int;
 568    pragma Import (C, sched_yield, "sched_yield");
 569
 570    ---------------------------
 571    -- P1003.1c - Section 16 --
 572    ---------------------------
 573
 574    function pthread_attr_init
 575      (attributes : access pthread_attr_t) return int;
 576    pragma Import (C, pthread_attr_init, "pthread_attr_init");
 577
 578    function pthread_attr_destroy
 579      (attributes : access pthread_attr_t) return int;
 580    pragma Import (C, pthread_attr_destroy, "pthread_attr_destroy");
 581
 582    function pthread_attr_setdetachstate
 583      (attr        : access pthread_attr_t;
 584       detachstate : int) return int;
 585    pragma Import
 586      (C, pthread_attr_setdetachstate, "pthread_attr_setdetachstate");
 587
 588    function pthread_attr_setstacksize
 589      (attr      : access pthread_attr_t;
 590       stacksize : size_t) return int;
 591    pragma Import (C, pthread_attr_setstacksize, "pthread_attr_setstacksize");
 592
 593    --  From: /usr/include/pthread/pthread.h
 594    function pthread_create
 595      (thread        : access pthread_t;
 596       attributes    : access pthread_attr_t;
 597       start_routine : Thread_Body;
 598       arg           : System.Address) return int;
 599    pragma Import (C, pthread_create, "pthread_create");
 600
 601    procedure pthread_exit (status : System.Address);
 602    pragma Import (C, pthread_exit, "pthread_exit");
 603
 604    function pthread_self return pthread_t;
 605    pragma Import (C, pthread_self, "pthread_self");
 606
 607    --------------------------
 608    -- POSIX.1c  Section 17 --
 609    --------------------------
 610
 611    function pthread_setspecific
 612      (key   : pthread_key_t;
 613       value : System.Address) return int;
 614    pragma Import (C, pthread_setspecific, "pthread_setspecific");
 615
 616    function pthread_getspecific (key : pthread_key_t) return System.Address;
 617    pragma Import (C, pthread_getspecific, "pthread_getspecific");
 618
 619    type destructor_pointer is access procedure (arg : System.Address);
 620    pragma Convention (C, destructor_pointer);
 621
 622    function pthread_key_create
 623      (key        : access pthread_key_t;
 624       destructor : destructor_pointer) return int;
 625    pragma Import (C, pthread_key_create, "pthread_key_create");
 626
 627    --  From /usr/include/i386-gnu/bits/sched.h
 628    CPU_SETSIZE : constant := 1_024;
 629
 630    type bit_field is array (1 .. CPU_SETSIZE) of Boolean;
 631    for bit_field'Size use CPU_SETSIZE;
 632    pragma Pack (bit_field);
 633    pragma Convention (C, bit_field);
 634
 635    type cpu_set_t is record
 636       bits : bit_field;
 637    end record;
 638    pragma Convention (C, cpu_set_t);
 639
 640 private
 641
 642    type sigset_t is array (1 .. 4) of unsigned;
 643
 644    --  In GNU/Hurd the component sa_handler turns out to
 645    --  be one a union type, and the selector is a macro:
 646    --  #define sa_handler __sigaction_handler.sa_handler
 647    --  #define sa_sigaction __sigaction_handler.sa_sigaction
 648
 649    --  Should we add a signal_context type here ?
 650    --  How could it be done independent of the CPU architecture ?
 651    --  sigcontext type is opaque, so it is architecturally neutral.
 652    --  It is always passed as an access type, so define it as an empty record
 653    --  since the contents are not used anywhere.
 654    type struct_sigcontext is null record;
 655    pragma Convention (C, struct_sigcontext);
 656
 657    type pid_t is new int;
 658
 659    type time_t is range -2 ** (System.Parameters.time_t_bits - 1)
 660      .. 2 ** (System.Parameters.time_t_bits - 1) - 1;
 661
 662    type timespec is record
 663       tv_sec  : time_t;
 664       tv_nsec : long;
 665    end record;
 666    pragma Convention (C, timespec);
 667
 668    --  From: /usr/include/pthread/pthreadtypes.h:
 669    --  typedef struct __pthread_attr pthread_attr_t;
 670    --  /usr/include/i386-gnu/bits/thread-attr.h: struct __pthread_attr...
 671    --  /usr/include/pthread/pthreadtypes.h: enum __pthread_contentionscope
 672    --   enum __pthread_detachstate detachstate;
 673    --   enum __pthread_inheritsched inheritsched;
 674    --   enum __pthread_contentionscope contentionscope;
 675    --   Not used: schedpolicy   : int;
 676    type pthread_attr_t is record
 677       schedparam    : struct_sched_param;
 678       stackaddr     : System.Address;
 679       stacksize     : size_t;
 680       guardsize     : size_t;
 681       detachstate   : int;
 682       inheritsched  : int;
 683       contentionscope : int;
 684       schedpolicy   : int;
 685    end record;
 686    pragma Convention (C, pthread_attr_t);
 687
 688    --  From: /usr/include/pthread/pthreadtypes.h:
 689    --  typedef struct __pthread_condattr pthread_condattr_t;
 690    --  From: /usr/include/i386-gnu/bits/condition-attr.h:
 691    --  struct __pthread_condattr {
 692    --    enum __pthread_process_shared pshared;
 693    --    __Clockid_T Clock;}
 694    --  From: /usr/include/pthread/pthreadtypes.h:
 695    --  enum __pthread_process_shared
 696    type pthread_condattr_t is record
 697       pshared : int;
 698       clock   : clockid_t;
 699    end record;
 700    pragma Convention (C, pthread_condattr_t);
 701
 702    --  From: /usr/include/pthread/pthreadtypes.h:
 703    --  typedef struct __pthread_mutexattr pthread_mutexattr_t; and
 704    --  /usr/include/i386-gnu/bits/mutex-attr.h
 705    --  struct __pthread_mutexattr {
 706    --  int prioceiling;
 707    --  enum __pthread_mutex_protocol protocol;
 708    --  enum __pthread_process_shared pshared;
 709    --  enum __pthread_mutex_type mutex_type;};
 710    type pthread_mutexattr_t is record
 711       prioceiling : int;
 712       protocol    : int;
 713       pshared     : int;
 714       mutex_type  : int;
 715    end record;
 716    pragma Convention (C, pthread_mutexattr_t);
 717
 718    --  From: /usr/include/pthread/pthreadtypes.h:
 719    --  typedef struct __pthread_cond pthread_cond_t;
 720    --  typedef struct __pthread_condattr pthread_condattr_t;
 721    --  /usr/include/i386-gnu/bits/condition.h:struct __pthread_cond{}
 722    --  pthread_condattr_t: see above!
 723    --  /usr/include/i386-gnu/bits/condition.h:
 724    --  struct __pthread_condimpl *__impl;
 725
 726    type pthread_cond_t is record
 727       lock       : int;
 728       queue      : System.Address;
 729       condattr   : System.Address;
 730       impl       : System.Address;
 731       data       : System.Address;
 732    end record;
 733    pragma Convention (C, pthread_cond_t);
 734
 735    --  From: /usr/include/pthread/pthreadtypes.h:
 736    --  typedef __pthread_key pthread_key_t; and
 737    --  /usr/include/i386-gnu/bits/thread-specific.h:
 738    --  typedef int __pthread_key;
 739
 740    type pthread_key_t is new int;
 741
 742    --  From: /usr/include/i386-gnu/bits/rwlock-attr.h:
 743    --  struct __pthread_rwlockattr {
 744    --  enum __pthread_process_shared pshared; };
 745
 746    type pthread_rwlockattr_t is record
 747       pshared : int;
 748    end record;
 749    pragma Convention (C, pthread_rwlockattr_t);
 750
 751    --  From: /usr/include/i386-gnu/bits/rwlock.h:
 752    --  struct __pthread_rwlock {
 753    --  __pthread_spinlock_t __held;
 754    --  __pthread_spinlock_t __lock;
 755    --  int readers;
 756    --  struct __pthread *readerqueue;
 757    --  struct __pthread *writerqueue;
 758    --  struct __pthread_rwlockattr *__attr;
 759    --  void *__data; };
 760
 761    type pthread_rwlock_t is record
 762       held        : int;
 763       lock        : int;
 764       readers     : int;
 765       readerqueue : System.Address;
 766       writerqueue : System.Address;
 767       attr        : pthread_rwlockattr_t;
 768       data        : int;
 769    end record;
 770    pragma Convention (C, pthread_rwlock_t);
 771
 772 end System.OS_Interface;