gcc/ada/s-osinte-kfreebsd-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) 1995-2015, 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/kFreeBSD (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 Interfaces.C;
  42 with Unchecked_Conversion;
  43
  44 package System.OS_Interface is
  45    pragma Preelaborate;
  46
  47    pragma Linker_Options ("-lpthread");
  48
  49    subtype int            is Interfaces.C.int;
  50    subtype char           is Interfaces.C.char;
  51    subtype short          is Interfaces.C.short;
  52    subtype long           is Interfaces.C.long;
  53    subtype unsigned       is Interfaces.C.unsigned;
  54    subtype unsigned_short is Interfaces.C.unsigned_short;
  55    subtype unsigned_long  is Interfaces.C.unsigned_long;
  56    subtype unsigned_char  is Interfaces.C.unsigned_char;
  57    subtype plain_char     is Interfaces.C.plain_char;
  58    subtype size_t         is Interfaces.C.size_t;
  59
  60    -----------
  61    -- Errno --
  62    -----------
  63
  64    function errno return int;
  65    pragma Import (C, errno, "__get_errno");
  66
  67    EAGAIN   : constant := 35;
  68    EINTR    : constant := 4;
  69    EINVAL   : constant := 22;
  70    ENOMEM   : constant := 12;
  71    EPERM    : constant := 1;
  72    ETIMEDOUT    : constant := 60;
  73
  74    -------------
  75    -- Signals --
  76    -------------
  77
  78    Max_Interrupt : constant := 128;
  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    SIGLTHRRES : constant := 32; --  GNU/LinuxThreads restart signal
 116    SIGLTHRCAN : constant := 33; --  GNU/LinuxThreads cancel signal
 117    SIGLTHRDBG : constant := 34; --  GNU/LinuxThreads debugger signal
 118
 119    SIGADAABORT : constant := SIGABRT;
 120    --  Change this if you want to use another signal for task abort.
 121    --  SIGTERM might be a good one.
 122
 123    type Signal_Set is array (Natural range <>) of Signal;
 124
 125    Unmasked    : constant Signal_Set := (
 126       SIGTRAP,
 127       --  To enable debugging on multithreaded applications, mark SIGTRAP to
 128       --  be kept unmasked.
 129
 130       SIGBUS,
 131
 132       SIGTTIN, SIGTTOU, SIGTSTP,
 133       --  Keep these three signals unmasked so that background processes
 134       --  and IO behaves as normal "C" applications
 135
 136       SIGPROF,
 137       --  To avoid confusing the profiler
 138
 139       SIGKILL, SIGSTOP,
 140       --  These two signals actually cannot be masked;
 141       --  POSIX simply won't allow it.
 142
 143       SIGLTHRRES, SIGLTHRCAN, SIGLTHRDBG);
 144       --  These three signals are used by GNU/LinuxThreads starting from
 145       --  glibc 2.1 (future 2.2).
 146
 147    Reserved    : constant Signal_Set :=
 148    --  I am not sure why the following signal is reserved.
 149    --  I guess they are not supported by this version of GNU/kFreeBSD.
 150      (0 .. 0 => SIGVTALRM);
 151
 152    type sigset_t is private;
 153
 154    function sigaddset (set : access sigset_t; sig : Signal) return int;
 155    pragma Import (C, sigaddset, "sigaddset");
 156
 157    function sigdelset (set : access sigset_t; sig : Signal) return int;
 158    pragma Import (C, sigdelset, "sigdelset");
 159
 160    function sigfillset (set : access sigset_t) return int;
 161    pragma Import (C, sigfillset, "sigfillset");
 162
 163    function sigismember (set : access sigset_t; sig : Signal) return int;
 164    pragma Import (C, sigismember, "sigismember");
 165
 166    function sigemptyset (set : access sigset_t) return int;
 167    pragma Import (C, sigemptyset, "sigemptyset");
 168
 169    --  sigcontext is architecture dependent, so define it private
 170    type struct_sigcontext is private;
 171
 172    type struct_sigaction is record
 173       sa_handler : System.Address;
 174       sa_flags   : int;
 175       sa_mask    : sigset_t;
 176    end record;
 177    pragma Convention (C, struct_sigaction);
 178
 179    type struct_sigaction_ptr is access all struct_sigaction;
 180
 181    SIG_BLOCK   : constant := 1;
 182    SIG_UNBLOCK : constant := 2;
 183    SIG_SETMASK : constant := 3;
 184
 185    SIG_DFL : constant := 0;
 186    SIG_IGN : constant := 1;
 187
 188    SA_SIGINFO : constant := 16#0040#;
 189    SA_ONSTACK : constant := 16#0001#;
 190
 191    function sigaction
 192      (sig  : Signal;
 193       act  : struct_sigaction_ptr;
 194       oact : struct_sigaction_ptr) return int;
 195    pragma Import (C, sigaction, "sigaction");
 196
 197    ----------
 198    -- Time --
 199    ----------
 200
 201    Time_Slice_Supported : constant Boolean := True;
 202    --  Indicates whether time slicing is supported (i.e SCHED_RR is supported)
 203
 204    type timespec is private;
 205
 206    function nanosleep (rqtp, rmtp : access timespec) return int;
 207    pragma Import (C, nanosleep, "nanosleep");
 208
 209    type clockid_t is private;
 210
 211    CLOCK_REALTIME : constant clockid_t;
 212
 213    function clock_gettime
 214      (clock_id : clockid_t;
 215       tp       : access timespec)
 216       return int;
 217    pragma Import (C, clock_gettime, "clock_gettime");
 218
 219    function To_Duration (TS : timespec) return Duration;
 220    pragma Inline (To_Duration);
 221
 222    function To_Timespec (D : Duration) return timespec;
 223    pragma Inline (To_Timespec);
 224
 225    function sysconf (name : int) return long;
 226    pragma Import (C, sysconf);
 227
 228    SC_CLK_TCK          : constant := 2;
 229    SC_NPROCESSORS_ONLN : constant := 84;
 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      Unchecked_Conversion (System.Address, Thread_Body);
 275
 276    type pthread_t is new unsigned_long;
 277    subtype Thread_Id        is pthread_t;
 278
 279    function To_pthread_t is new Unchecked_Conversion
 280      (unsigned_long, pthread_t);
 281
 282    type pthread_mutex_t     is limited private;
 283    type pthread_cond_t      is limited private;
 284    type pthread_attr_t      is limited private;
 285    type pthread_mutexattr_t is limited private;
 286    type pthread_condattr_t  is limited private;
 287    type pthread_key_t       is private;
 288
 289    PTHREAD_CREATE_DETACHED : constant := 1;
 290    PTHREAD_CREATE_JOINABLE : constant := 0;
 291
 292    PTHREAD_SCOPE_PROCESS : constant := 0;
 293    PTHREAD_SCOPE_SYSTEM  : constant := 2;
 294
 295    --  Read/Write lock not supported on kfreebsd. To add support both types
 296    --  pthread_rwlock_t and pthread_rwlockattr_t must properly be defined
 297    --  with the associated routines pthread_rwlock_[init/destroy] and
 298    --  pthread_rwlock_[rdlock/wrlock/unlock].
 299
 300    subtype pthread_rwlock_t     is pthread_mutex_t;
 301    subtype pthread_rwlockattr_t is pthread_mutexattr_t;
 302
 303    -----------
 304    -- Stack --
 305    -----------
 306
 307    type stack_t is record
 308       ss_sp    : System.Address;
 309       ss_size  : size_t;
 310       ss_flags : int;
 311    end record;
 312    pragma Convention (C, stack_t);
 313
 314    function sigaltstack
 315      (ss  : not null access stack_t;
 316       oss : access stack_t) return int;
 317    pragma Import (C, sigaltstack, "sigaltstack");
 318
 319    Alternate_Stack : aliased System.Address;
 320    --  This is a dummy definition, never used (Alternate_Stack_Size is null)
 321
 322    Alternate_Stack_Size : constant := 0;
 323    --  No alternate signal stack is used on this platform
 324
 325    Stack_Base_Available : constant Boolean := False;
 326    --  Indicates whether the stack base is available on this target
 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 size_t;
 334    function Get_Page_Size return Address;
 335    pragma Import (C, Get_Page_Size, "getpagesize");
 336    --  Returns the size of a page
 337
 338    PROT_NONE  : constant := 0;
 339    PROT_READ  : constant := 1;
 340    PROT_WRITE : constant := 2;
 341    PROT_EXEC  : constant := 4;
 342    PROT_ALL   : constant := PROT_READ + PROT_WRITE + PROT_EXEC;
 343    PROT_ON    : constant := PROT_NONE;
 344    PROT_OFF   : constant := PROT_ALL;
 345
 346    function mprotect (addr : Address; len : size_t; prot : int) return int;
 347    pragma Import (C, mprotect);
 348
 349    ---------------------------------------
 350    -- Nonstandard Thread Initialization --
 351    ---------------------------------------
 352
 353    procedure pthread_init;
 354    pragma Inline (pthread_init);
 355    --  This is a dummy procedure to share some GNULLI files
 356
 357    -------------------------
 358    -- POSIX.1c  Section 3 --
 359    -------------------------
 360
 361    function sigwait (set : access sigset_t; sig : access Signal) return int;
 362    pragma Import (C, sigwait, "sigwait");
 363
 364    function pthread_kill (thread : pthread_t; sig : Signal) return int;
 365    pragma Import (C, pthread_kill, "pthread_kill");
 366
 367    function pthread_sigmask
 368      (how  : int;
 369       set  : access sigset_t;
 370       oset : access sigset_t) return int;
 371    pragma Import (C, pthread_sigmask, "pthread_sigmask");
 372
 373    --------------------------
 374    -- POSIX.1c  Section 11 --
 375    --------------------------
 376
 377    function pthread_mutexattr_init
 378      (attr : access pthread_mutexattr_t) return int;
 379    pragma Import (C, pthread_mutexattr_init, "pthread_mutexattr_init");
 380
 381    function pthread_mutexattr_destroy
 382      (attr : access pthread_mutexattr_t) return int;
 383    pragma Import (C, pthread_mutexattr_destroy, "pthread_mutexattr_destroy");
 384
 385    function pthread_mutex_init
 386      (mutex : access pthread_mutex_t;
 387       attr  : access pthread_mutexattr_t) return int;
 388    pragma Import (C, pthread_mutex_init, "pthread_mutex_init");
 389
 390    function pthread_mutex_destroy (mutex : access pthread_mutex_t) return int;
 391    pragma Import (C, pthread_mutex_destroy, "pthread_mutex_destroy");
 392
 393    function pthread_mutex_lock (mutex : access pthread_mutex_t) return int;
 394    pragma Import (C, pthread_mutex_lock, "pthread_mutex_lock");
 395
 396    function pthread_mutex_unlock (mutex : access pthread_mutex_t) return int;
 397    pragma Import (C, pthread_mutex_unlock, "pthread_mutex_unlock");
 398
 399    function pthread_condattr_init
 400      (attr : access pthread_condattr_t) return int;
 401    pragma Import (C, pthread_condattr_init, "pthread_condattr_init");
 402
 403    function pthread_condattr_destroy
 404      (attr : access pthread_condattr_t) return int;
 405    pragma Import (C, pthread_condattr_destroy, "pthread_condattr_destroy");
 406
 407    function pthread_cond_init
 408      (cond : access pthread_cond_t;
 409       attr : access pthread_condattr_t) return int;
 410    pragma Import (C, pthread_cond_init, "pthread_cond_init");
 411
 412    function pthread_cond_destroy (cond : access pthread_cond_t) return int;
 413    pragma Import (C, pthread_cond_destroy, "pthread_cond_destroy");
 414
 415    function pthread_cond_signal (cond : access pthread_cond_t) return int;
 416    pragma Import (C, pthread_cond_signal, "pthread_cond_signal");
 417
 418    function pthread_cond_wait
 419      (cond  : access pthread_cond_t;
 420       mutex : access pthread_mutex_t) return int;
 421    pragma Import (C, pthread_cond_wait, "pthread_cond_wait");
 422
 423    function pthread_cond_timedwait
 424      (cond    : access pthread_cond_t;
 425       mutex   : access pthread_mutex_t;
 426       abstime : access timespec) return int;
 427    pragma Import (C, pthread_cond_timedwait, "pthread_cond_timedwait");
 428
 429    Relative_Timed_Wait : constant Boolean := False;
 430    --  pthread_cond_timedwait requires an absolute delay time
 431
 432    --------------------------
 433    -- POSIX.1c  Section 13 --
 434    --------------------------
 435
 436    PTHREAD_PRIO_NONE    : constant := 0;
 437    PTHREAD_PRIO_PROTECT : constant := 2;
 438    PTHREAD_PRIO_INHERIT : constant := 1;
 439
 440    function pthread_mutexattr_setprotocol
 441      (attr     : access pthread_mutexattr_t;
 442       protocol : int) return int;
 443    pragma Import
 444       (C, pthread_mutexattr_setprotocol, "pthread_mutexattr_setprotocol");
 445
 446    function pthread_mutexattr_getprotocol
 447      (attr     : access pthread_mutexattr_t;
 448       protocol : access int) return int;
 449    pragma Import
 450      (C, pthread_mutexattr_getprotocol, "pthread_mutexattr_getprotocol");
 451
 452    function pthread_mutexattr_setprioceiling
 453      (attr     : access pthread_mutexattr_t;
 454       prioceiling : int) return int;
 455    pragma Import
 456      (C, pthread_mutexattr_setprioceiling,
 457       "pthread_mutexattr_setprioceiling");
 458
 459    function pthread_mutexattr_getprioceiling
 460      (attr     : access pthread_mutexattr_t;
 461       prioceiling : access int) return int;
 462    pragma Import
 463      (C, pthread_mutexattr_getprioceiling,
 464       "pthread_mutexattr_getprioceiling");
 465
 466    type struct_sched_param is record
 467       sched_priority : int;  --  scheduling priority
 468    end record;
 469    pragma Convention (C, struct_sched_param);
 470
 471    function pthread_setschedparam
 472      (thread : pthread_t;
 473       policy : int;
 474       param  : access struct_sched_param) return int;
 475    pragma Import (C, pthread_setschedparam, "pthread_setschedparam");
 476
 477    function pthread_attr_setscope
 478      (attr            : access pthread_attr_t;
 479       contentionscope : int) return int;
 480    pragma Import (C, pthread_attr_setscope, "pthread_attr_setscope");
 481
 482    function pthread_attr_getscope
 483      (attr            : access pthread_attr_t;
 484       contentionscope : access int) return int;
 485    pragma Import (C, pthread_attr_getscope, "pthread_attr_getscope");
 486
 487    function pthread_attr_setinheritsched
 488      (attr            : access pthread_attr_t;
 489       inheritsched : int) return int;
 490    pragma Import
 491      (C, pthread_attr_setinheritsched, "pthread_attr_setinheritsched");
 492
 493    function pthread_attr_getinheritsched
 494      (attr         : access pthread_attr_t;
 495       inheritsched : access int) return int;
 496    pragma Import
 497      (C, pthread_attr_getinheritsched, "pthread_attr_getinheritsched");
 498
 499    function pthread_attr_setschedpolicy
 500      (attr   : access pthread_attr_t;
 501       policy : int) return int;
 502    pragma Import
 503      (C, pthread_attr_setschedpolicy, "pthread_attr_setschedpolicy");
 504
 505    function sched_yield return int;
 506    pragma Import (C, sched_yield, "sched_yield");
 507
 508    ---------------------------
 509    -- P1003.1c - Section 16 --
 510    ---------------------------
 511
 512    function pthread_attr_init
 513      (attributes : access pthread_attr_t) return int;
 514    pragma Import (C, pthread_attr_init, "pthread_attr_init");
 515
 516    function pthread_attr_destroy
 517      (attributes : access pthread_attr_t) return int;
 518    pragma Import (C, pthread_attr_destroy, "pthread_attr_destroy");
 519
 520    function pthread_attr_setdetachstate
 521      (attr        : access pthread_attr_t;
 522       detachstate : int) return int;
 523    pragma Import
 524      (C, pthread_attr_setdetachstate, "pthread_attr_setdetachstate");
 525
 526    function pthread_attr_setstacksize
 527      (attr      : access pthread_attr_t;
 528       stacksize : size_t) return int;
 529    pragma Import (C, pthread_attr_setstacksize, "pthread_attr_setstacksize");
 530
 531    function pthread_create
 532      (thread        : access pthread_t;
 533       attributes    : access pthread_attr_t;
 534       start_routine : Thread_Body;
 535       arg           : System.Address) return int;
 536    pragma Import (C, pthread_create, "pthread_create");
 537
 538    procedure pthread_exit (status : System.Address);
 539    pragma Import (C, pthread_exit, "pthread_exit");
 540
 541    function pthread_self return pthread_t;
 542    pragma Import (C, pthread_self, "pthread_self");
 543
 544    --------------------------
 545    -- POSIX.1c  Section 17 --
 546    --------------------------
 547
 548    function pthread_setspecific
 549      (key   : pthread_key_t;
 550       value : System.Address) return int;
 551    pragma Import (C, pthread_setspecific, "pthread_setspecific");
 552
 553    function pthread_getspecific (key : pthread_key_t) return System.Address;
 554    pragma Import (C, pthread_getspecific, "pthread_getspecific");
 555
 556    type destructor_pointer is access procedure (arg : System.Address);
 557    pragma Convention (C, destructor_pointer);
 558
 559    function pthread_key_create
 560      (key        : access pthread_key_t;
 561       destructor : destructor_pointer) return int;
 562    pragma Import (C, pthread_key_create, "pthread_key_create");
 563
 564    CPU_SETSIZE : constant := 1_024;
 565
 566    type bit_field is array (1 .. CPU_SETSIZE) of Boolean;
 567    for bit_field'Size use CPU_SETSIZE;
 568    pragma Pack (bit_field);
 569    pragma Convention (C, bit_field);
 570
 571    type cpu_set_t is record
 572       bits : bit_field;
 573    end record;
 574    pragma Convention (C, cpu_set_t);
 575
 576    function pthread_setaffinity_np
 577      (thread     : pthread_t;
 578       cpusetsize : size_t;
 579       cpuset     : access cpu_set_t) return int;
 580    pragma Import (C, pthread_setaffinity_np, "__gnat_pthread_setaffinity_np");
 581
 582 private
 583
 584    type sigset_t is array (1 .. 4) of unsigned;
 585
 586    --  In FreeBSD the component sa_handler turns out to
 587    --  be one a union type, and the selector is a macro:
 588    --  #define sa_handler __sigaction_u._handler
 589    --  #define sa_sigaction __sigaction_u._sigaction
 590
 591    --  Should we add a signal_context type here ?
 592    --  How could it be done independent of the CPU architecture ?
 593    --  sigcontext type is opaque, so it is architecturally neutral.
 594    --  It is always passed as an access type, so define it as an empty record
 595    --  since the contents are not used anywhere.
 596    type struct_sigcontext is null record;
 597    pragma Convention (C, struct_sigcontext);
 598
 599    type pid_t is new int;
 600
 601    type time_t is new long;
 602
 603    type timespec is record
 604       tv_sec  : time_t;
 605       tv_nsec : long;
 606    end record;
 607    pragma Convention (C, timespec);
 608
 609    type clockid_t is new int;
 610    CLOCK_REALTIME : constant clockid_t := 0;
 611
 612    type pthread_attr_t is record
 613       detachstate   : int;
 614       schedpolicy   : int;
 615       schedparam    : struct_sched_param;
 616       inheritsched  : int;
 617       scope         : int;
 618       guardsize     : size_t;
 619       stackaddr_set : int;
 620       stackaddr     : System.Address;
 621       stacksize     : size_t;
 622    end record;
 623    pragma Convention (C, pthread_attr_t);
 624
 625    type pthread_condattr_t is record
 626       dummy : int;
 627    end record;
 628    pragma Convention (C, pthread_condattr_t);
 629
 630    type pthread_mutexattr_t is record
 631       mutexkind : int;
 632    end record;
 633    pragma Convention (C, pthread_mutexattr_t);
 634
 635    type struct_pthread_fast_lock is record
 636       status   : long;
 637       spinlock : int;
 638    end record;
 639    pragma Convention (C, struct_pthread_fast_lock);
 640
 641    type pthread_mutex_t is record
 642       m_reserved : int;
 643       m_count    : int;
 644       m_owner    : System.Address;
 645       m_kind     : int;
 646       m_lock     : struct_pthread_fast_lock;
 647    end record;
 648    pragma Convention (C, pthread_mutex_t);
 649
 650    type pthread_cond_t is array (0 .. 47) of unsigned_char;
 651    pragma Convention (C, pthread_cond_t);
 652
 653    type pthread_key_t is new unsigned;
 654
 655 end System.OS_Interface;