gcc/ada/s-osinte-freebsd.ads

   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) 1995-2014, 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 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 (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. This
 326    --  allows us to share s-osinte.adb between all the FSU run time. Note that
 327    --  this value can only be true if pthread_t has a complete definition that
 328    --  corresponds exactly to the C header files.
 329
 330    function Get_Stack_Base (thread : pthread_t) return Address;
 331    pragma Inline (Get_Stack_Base);
 332    --  returns the stack base of the specified thread. Only call this function
 333    --  when Stack_Base_Available is True.
 334
 335    function Get_Page_Size return size_t;
 336    function Get_Page_Size return Address;
 337    pragma Import (C, Get_Page_Size, "getpagesize");
 338    --  Returns the size of a page
 339
 340    PROT_NONE  : constant := 0;
 341    PROT_READ  : constant := 1;
 342    PROT_WRITE : constant := 2;
 343    PROT_EXEC  : constant := 4;
 344    PROT_ALL   : constant := PROT_READ + PROT_WRITE + PROT_EXEC;
 345    PROT_ON    : constant := PROT_NONE;
 346    PROT_OFF   : constant := PROT_ALL;
 347
 348    function mprotect (addr : Address; len : size_t; prot : int) return int;
 349    pragma Import (C, mprotect);
 350
 351    ---------------------------------------
 352    -- Nonstandard Thread Initialization --
 353    ---------------------------------------
 354
 355    --  FSU_THREADS requires pthread_init, which is nonstandard and this should
 356    --  be invoked during the elaboration of s-taprop.adb.
 357
 358    --  FreeBSD does not require this so we provide an empty Ada body
 359
 360    procedure pthread_init;
 361
 362    -------------------------
 363    -- POSIX.1c  Section 3 --
 364    -------------------------
 365
 366    function sigwait
 367      (set : access sigset_t;
 368       sig : access Signal) return int;
 369    pragma Import (C, sigwait, "sigwait");
 370
 371    function pthread_kill
 372      (thread : pthread_t;
 373       sig    : Signal) return int;
 374    pragma Import (C, pthread_kill, "pthread_kill");
 375
 376    function pthread_sigmask
 377      (how  : int;
 378       set  : access sigset_t;
 379       oset : access sigset_t) return int;
 380    pragma Import (C, pthread_sigmask, "pthread_sigmask");
 381
 382    --------------------------
 383    -- POSIX.1c  Section 11 --
 384    --------------------------
 385
 386    function pthread_mutexattr_init
 387      (attr : access pthread_mutexattr_t) return int;
 388    pragma Import (C, pthread_mutexattr_init, "pthread_mutexattr_init");
 389
 390    function pthread_mutexattr_destroy
 391      (attr : access pthread_mutexattr_t) return int;
 392    pragma Import (C, pthread_mutexattr_destroy, "pthread_mutexattr_destroy");
 393
 394    function pthread_mutex_init
 395      (mutex : access pthread_mutex_t;
 396       attr  : access pthread_mutexattr_t) return int;
 397    pragma Import (C, pthread_mutex_init, "pthread_mutex_init");
 398
 399    function pthread_mutex_destroy (mutex : access pthread_mutex_t) return int;
 400    pragma Import (C, pthread_mutex_destroy, "pthread_mutex_destroy");
 401
 402    function pthread_mutex_lock (mutex : access pthread_mutex_t) return int;
 403    pragma Import (C, pthread_mutex_lock, "pthread_mutex_lock");
 404
 405    function pthread_mutex_unlock (mutex : access pthread_mutex_t) return int;
 406    pragma Import (C, pthread_mutex_unlock, "pthread_mutex_unlock");
 407
 408    function pthread_condattr_init
 409      (attr : access pthread_condattr_t) return int;
 410    pragma Import (C, pthread_condattr_init, "pthread_condattr_init");
 411
 412    function pthread_condattr_destroy
 413      (attr : access pthread_condattr_t) return int;
 414    pragma Import (C, pthread_condattr_destroy, "pthread_condattr_destroy");
 415
 416    function pthread_cond_init
 417      (cond : access pthread_cond_t;
 418       attr : access pthread_condattr_t) return int;
 419    pragma Import (C, pthread_cond_init, "pthread_cond_init");
 420
 421    function pthread_cond_destroy (cond : access pthread_cond_t) return int;
 422    pragma Import (C, pthread_cond_destroy, "pthread_cond_destroy");
 423
 424    function pthread_cond_signal (cond : access pthread_cond_t) return int;
 425    pragma Import (C, pthread_cond_signal, "pthread_cond_signal");
 426
 427    function pthread_cond_wait
 428      (cond  : access pthread_cond_t;
 429       mutex : access pthread_mutex_t) return int;
 430    pragma Import (C, pthread_cond_wait, "pthread_cond_wait");
 431
 432    function pthread_cond_timedwait
 433      (cond    : access pthread_cond_t;
 434       mutex   : access pthread_mutex_t;
 435       abstime : access timespec) return int;
 436    pragma Import (C, pthread_cond_timedwait, "pthread_cond_timedwait");
 437
 438    Relative_Timed_Wait : constant Boolean := False;
 439    --  pthread_cond_timedwait requires an absolute delay time
 440
 441    --------------------------
 442    -- POSIX.1c  Section 13 --
 443    --------------------------
 444
 445    PTHREAD_PRIO_NONE    : constant := 0;
 446    PTHREAD_PRIO_PROTECT : constant := 2;
 447    PTHREAD_PRIO_INHERIT : constant := 1;
 448
 449    function pthread_mutexattr_setprotocol
 450      (attr     : access pthread_mutexattr_t;
 451       protocol : int) return int;
 452    pragma Import
 453       (C, pthread_mutexattr_setprotocol, "pthread_mutexattr_setprotocol");
 454
 455    function pthread_mutexattr_getprotocol
 456      (attr     : access pthread_mutexattr_t;
 457       protocol : access int) return int;
 458    pragma Import
 459      (C, pthread_mutexattr_getprotocol, "pthread_mutexattr_getprotocol");
 460
 461    function pthread_mutexattr_setprioceiling
 462      (attr     : access pthread_mutexattr_t;
 463       prioceiling : int) return int;
 464    pragma Import
 465      (C, pthread_mutexattr_setprioceiling,
 466       "pthread_mutexattr_setprioceiling");
 467
 468    function pthread_mutexattr_getprioceiling
 469      (attr     : access pthread_mutexattr_t;
 470       prioceiling : access int) return int;
 471    pragma Import
 472      (C, pthread_mutexattr_getprioceiling,
 473       "pthread_mutexattr_getprioceiling");
 474
 475    type struct_sched_param is record
 476       sched_priority : int;
 477    end record;
 478    pragma Convention (C, struct_sched_param);
 479
 480    function pthread_getschedparam
 481      (thread : pthread_t;
 482       policy : access int;
 483       param  : access struct_sched_param) return int;
 484    pragma Import (C, pthread_getschedparam, "pthread_getschedparam");
 485
 486    function pthread_setschedparam
 487      (thread : pthread_t;
 488       policy : int;
 489       param  : access struct_sched_param) return int;
 490    pragma Import (C, pthread_setschedparam, "pthread_setschedparam");
 491
 492    function pthread_attr_setscope
 493      (attr            : access pthread_attr_t;
 494       contentionscope : int) return int;
 495    pragma Import (C, pthread_attr_setscope, "pthread_attr_setscope");
 496
 497    function pthread_attr_getscope
 498      (attr            : access pthread_attr_t;
 499       contentionscope : access int) return int;
 500    pragma Import (C, pthread_attr_getscope, "pthread_attr_getscope");
 501
 502    function pthread_attr_setinheritsched
 503      (attr            : access pthread_attr_t;
 504       inheritsched : int) return int;
 505    pragma Import
 506      (C, pthread_attr_setinheritsched, "pthread_attr_setinheritsched");
 507
 508    function pthread_attr_getinheritsched
 509      (attr         : access pthread_attr_t;
 510       inheritsched : access int) return int;
 511    pragma Import
 512      (C, pthread_attr_getinheritsched, "pthread_attr_getinheritsched");
 513
 514    function pthread_attr_setschedpolicy
 515      (attr   : access pthread_attr_t;
 516       policy : int) return int;
 517    pragma Import (C, pthread_attr_setschedpolicy,
 518      "pthread_attr_setschedpolicy");
 519
 520    function pthread_attr_getschedpolicy
 521      (attr   : access pthread_attr_t;
 522       policy : access int) return int;
 523    pragma Import (C, pthread_attr_getschedpolicy,
 524      "pthread_attr_getschedpolicy");
 525
 526    function pthread_attr_setschedparam
 527      (attr        : access pthread_attr_t;
 528       sched_param : int) return int;
 529    pragma Import (C, pthread_attr_setschedparam, "pthread_attr_setschedparam");
 530
 531    function pthread_attr_getschedparam
 532      (attr        : access pthread_attr_t;
 533       sched_param : access int) return int;
 534    pragma Import (C, pthread_attr_getschedparam, "pthread_attr_getschedparam");
 535
 536    function sched_yield return int;
 537    pragma Import (C, sched_yield, "pthread_yield");
 538
 539    --------------------------
 540    -- P1003.1c  Section 16 --
 541    --------------------------
 542
 543    function pthread_attr_init (attributes : access pthread_attr_t) return int;
 544    pragma Import (C, pthread_attr_init, "pthread_attr_init");
 545
 546    function pthread_attr_destroy
 547      (attributes : access pthread_attr_t) return int;
 548    pragma Import (C, pthread_attr_destroy, "pthread_attr_destroy");
 549
 550    function pthread_attr_setdetachstate
 551      (attr        : access pthread_attr_t;
 552       detachstate : int) return int;
 553    pragma Import
 554      (C, pthread_attr_setdetachstate, "pthread_attr_setdetachstate");
 555
 556    function pthread_attr_getdetachstate
 557      (attr        : access pthread_attr_t;
 558       detachstate : access int) return int;
 559    pragma Import
 560      (C, pthread_attr_getdetachstate, "pthread_attr_getdetachstate");
 561
 562    function pthread_attr_getstacksize
 563      (attr      : access pthread_attr_t;
 564       stacksize : access size_t) return int;
 565    pragma Import
 566      (C, pthread_attr_getstacksize, "pthread_attr_getstacksize");
 567
 568    function pthread_attr_setstacksize
 569      (attr      : access pthread_attr_t;
 570       stacksize : size_t) return int;
 571    pragma Import
 572      (C, pthread_attr_setstacksize, "pthread_attr_setstacksize");
 573
 574    function pthread_create
 575      (thread        : access pthread_t;
 576       attributes    : access pthread_attr_t;
 577       start_routine : Thread_Body;
 578       arg           : System.Address) return int;
 579    pragma Import (C, pthread_create, "pthread_create");
 580
 581    function pthread_detach (thread : pthread_t) return int;
 582    pragma Import (C, pthread_detach, "pthread_detach");
 583
 584    procedure pthread_exit (status : System.Address);
 585    pragma Import (C, pthread_exit, "pthread_exit");
 586
 587    function pthread_self return pthread_t;
 588    pragma Import (C, pthread_self, "pthread_self");
 589
 590    --------------------------
 591    -- POSIX.1c  Section 17 --
 592    --------------------------
 593
 594    function pthread_setspecific
 595      (key   : pthread_key_t;
 596       value : System.Address) return  int;
 597    pragma Import (C, pthread_setspecific, "pthread_setspecific");
 598
 599    function pthread_getspecific (key : pthread_key_t) return System.Address;
 600    pragma Import (C, pthread_getspecific, "pthread_getspecific");
 601
 602    type destructor_pointer is access procedure (arg : System.Address);
 603    pragma Convention (C, destructor_pointer);
 604
 605    function pthread_key_create
 606      (key        : access pthread_key_t;
 607       destructor : destructor_pointer) return int;
 608    pragma Import (C, pthread_key_create, "pthread_key_create");
 609
 610    ------------------------------------
 611    -- Non-portable Pthread Functions --
 612    ------------------------------------
 613
 614    function pthread_set_name_np
 615      (thread : pthread_t;
 616       name   : System.Address) return int;
 617    pragma Import (C, pthread_set_name_np, "pthread_set_name_np");
 618
 619 private
 620
 621    type sigset_t is array (1 .. 4) of unsigned;
 622
 623    --  In FreeBSD the component sa_handler turns out to
 624    --  be one a union type, and the selector is a macro:
 625    --  #define sa_handler __sigaction_u._handler
 626    --  #define sa_sigaction __sigaction_u._sigaction
 627
 628    --  Should we add a signal_context type here ???
 629    --  How could it be done independent of the CPU architecture ???
 630    --  sigcontext type is opaque, so it is architecturally neutral.
 631    --  It is always passed as an access type, so define it as an empty record
 632    --  since the contents are not used anywhere.
 633
 634    type struct_sigcontext is null record;
 635    pragma Convention (C, struct_sigcontext);
 636
 637    type pid_t is new int;
 638    Self_PID : constant pid_t := 0;
 639
 640    type time_t is new long;
 641
 642    type timespec is record
 643       ts_sec  : time_t;
 644       ts_nsec : long;
 645    end record;
 646    pragma Convention (C, timespec);
 647
 648    type pthread_t           is new System.Address;
 649    type pthread_attr_t      is new System.Address;
 650    type pthread_mutex_t     is new System.Address;
 651    type pthread_mutexattr_t is new System.Address;
 652    type pthread_cond_t      is new System.Address;
 653    type pthread_condattr_t  is new System.Address;
 654    type pthread_key_t       is new int;
 655
 656 end System.OS_Interface;