gcc/ada/libgnarl/s-osinte__android.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) 1995-2017, Free Software Foundation, Inc.         --
  10 --                                                                          --
  11 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 3,  or (at your option) any later ver- --
  14 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
  17 --                                                                          --
  18 -- As a special exception under Section 7 of GPL version 3, you are granted --
  19 -- additional permissions described in the GCC Runtime Library Exception,   --
  20 -- version 3.1, as published by the Free Software Foundation.               --
  21 --                                                                          --
  22 -- You should have received a copy of the GNU General Public License and    --
  23 -- a copy of the GCC Runtime Library Exception along with this program;     --
  24 -- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
  25 -- <http://www.gnu.org/licenses/>.                                          --
  26 --                                                                          --
  27 -- GNARL was developed by the GNARL team at Florida State University.       --
  28 -- Extensive contributions were provided by Ada Core Technologies, Inc.     --
  29 --                                                                          --
  30 ------------------------------------------------------------------------------
  31
  32 --  This is an Android version of this package which is based on the
  33 --  GNU/Linux version
  34
  35 --  This package encapsulates all direct interfaces to OS services
  36 --  that are needed by the tasking run-time (libgnarl).
  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 with Interfaces.C;
  43 with System.Linux;
  44 with System.OS_Constants;
  45
  46 package System.OS_Interface is
  47    pragma Preelaborate;
  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 := System.Linux.EAGAIN;
  68    EINTR     : constant := System.Linux.EINTR;
  69    EINVAL    : constant := System.Linux.EINVAL;
  70    ENOMEM    : constant := System.Linux.ENOMEM;
  71    EPERM     : constant := System.Linux.EPERM;
  72    ETIMEDOUT : constant := System.Linux.ETIMEDOUT;
  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 := System.Linux.SIGHUP;
  83    SIGINT     : constant := System.Linux.SIGINT;
  84    SIGQUIT    : constant := System.Linux.SIGQUIT;
  85    SIGILL     : constant := System.Linux.SIGILL;
  86    SIGTRAP    : constant := System.Linux.SIGTRAP;
  87    SIGIOT     : constant := System.Linux.SIGIOT;
  88    SIGABRT    : constant := System.Linux.SIGABRT;
  89    SIGFPE     : constant := System.Linux.SIGFPE;
  90    SIGKILL    : constant := System.Linux.SIGKILL;
  91    SIGBUS     : constant := System.Linux.SIGBUS;
  92    SIGSEGV    : constant := System.Linux.SIGSEGV;
  93    SIGPIPE    : constant := System.Linux.SIGPIPE;
  94    SIGALRM    : constant := System.Linux.SIGALRM;
  95    SIGTERM    : constant := System.Linux.SIGTERM;
  96    SIGUSR1    : constant := System.Linux.SIGUSR1;
  97    SIGUSR2    : constant := System.Linux.SIGUSR2;
  98    SIGCLD     : constant := System.Linux.SIGCLD;
  99    SIGCHLD    : constant := System.Linux.SIGCHLD;
 100    SIGPWR     : constant := System.Linux.SIGPWR;
 101    SIGWINCH   : constant := System.Linux.SIGWINCH;
 102    SIGURG     : constant := System.Linux.SIGURG;
 103    SIGPOLL    : constant := System.Linux.SIGPOLL;
 104    SIGIO      : constant := System.Linux.SIGIO;
 105    SIGLOST    : constant := System.Linux.SIGLOST;
 106    SIGSTOP    : constant := System.Linux.SIGSTOP;
 107    SIGTSTP    : constant := System.Linux.SIGTSTP;
 108    SIGCONT    : constant := System.Linux.SIGCONT;
 109    SIGTTIN    : constant := System.Linux.SIGTTIN;
 110    SIGTTOU    : constant := System.Linux.SIGTTOU;
 111    SIGVTALRM  : constant := System.Linux.SIGVTALRM;
 112    SIGPROF    : constant := System.Linux.SIGPROF;
 113    SIGXCPU    : constant := System.Linux.SIGXCPU;
 114    SIGXFSZ    : constant := System.Linux.SIGXFSZ;
 115    SIGUNUSED  : constant := System.Linux.SIGUNUSED;
 116    SIGSTKFLT  : constant := System.Linux.SIGSTKFLT;
 117
 118    SIGADAABORT : constant := SIGABRT;
 119    --  Change this to use another signal for task abort. SIGTERM might be a
 120    --  good one.
 121
 122    type Signal_Set is array (Natural range <>) of Signal;
 123
 124    Unmasked : constant Signal_Set := (
 125       SIGTRAP,
 126       --  To enable debugging on multithreaded applications, mark SIGTRAP to
 127       --  be kept unmasked.
 128
 129       SIGBUS,
 130
 131       SIGTTIN, SIGTTOU, SIGTSTP,
 132       --  Keep these three signals unmasked so that background processes and IO
 133       --  behaves as normal "C" applications
 134
 135       SIGPROF,
 136       --  To avoid confusing the profiler
 137
 138       SIGKILL, SIGSTOP);
 139       --  These two signals actually can't be masked (POSIX won't allow it)
 140
 141    Reserved : constant Signal_Set := (SIGVTALRM, SIGUNUSED);
 142    --  Not clear why these two signals are reserved. Perhaps they are not
 143    --  supported by this version of GNU/Linux ???
 144
 145    type sigset_t is private;
 146
 147    function sigaddset (set : access sigset_t; sig : Signal) return int;
 148    pragma Import (C, sigaddset, "_sigaddset");
 149
 150    function sigdelset (set : access sigset_t; sig : Signal) return int;
 151    pragma Import (C, sigdelset, "_sigdelset");
 152
 153    function sigfillset (set : access sigset_t) return int;
 154    pragma Import (C, sigfillset, "_sigfillset");
 155
 156    function sigismember (set : access sigset_t; sig : Signal) return int;
 157    pragma Import (C, sigismember, "_sigismember");
 158
 159    function sigemptyset (set : access sigset_t) return int;
 160    pragma Import (C, sigemptyset, "_sigemptyset");
 161
 162    type union_type_3 is new String (1 .. 116);
 163    type siginfo_t is record
 164       si_signo : int;
 165       si_code  : int;
 166       si_errno : int;
 167       X_data   : union_type_3;
 168    end record;
 169    pragma Convention (C, siginfo_t);
 170
 171    type struct_sigaction is record
 172       sa_handler  : System.Address;
 173       sa_mask     : sigset_t;
 174       sa_flags    : Interfaces.C.unsigned_long;
 175       sa_restorer : System.Address;
 176    end record;
 177    pragma Convention (C, struct_sigaction);
 178
 179    type struct_sigaction_ptr is access all struct_sigaction;
 180
 181    SA_SIGINFO : constant := System.Linux.SA_SIGINFO;
 182    SA_ONSTACK : constant := System.Linux.SA_ONSTACK;
 183    SA_NODEFER : constant := System.Linux.SA_NODEFER;
 184    SA_RESTART : constant := System.Linux.SA_RESTART;
 185
 186    SIG_BLOCK   : constant := 0;
 187    SIG_UNBLOCK : constant := 1;
 188    SIG_SETMASK : constant := 2;
 189
 190    SIG_DFL : constant := 0;
 191    SIG_IGN : constant := 1;
 192
 193    function sigaction
 194      (sig  : Signal;
 195       act  : struct_sigaction_ptr;
 196       oact : struct_sigaction_ptr) return int;
 197    pragma Import (C, sigaction, "sigaction");
 198
 199    ----------
 200    -- Time --
 201    ----------
 202
 203    Time_Slice_Supported : constant Boolean := True;
 204    --  Indicates whether time slicing is supported
 205
 206    type timespec is private;
 207
 208    type clockid_t is new int;
 209
 210    function clock_gettime
 211      (clock_id : clockid_t; tp : access timespec) return int;
 212    pragma Import (C, clock_gettime, "clock_gettime");
 213
 214    function clock_getres
 215      (clock_id : clockid_t;
 216       res      : access timespec) return int;
 217    pragma Import (C, clock_getres, "clock_getres");
 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_OTHER : constant := 0;
 236    SCHED_FIFO  : constant := 1;
 237    SCHED_RR    : constant := 2;
 238
 239    function To_Target_Priority
 240      (Prio : System.Any_Priority)
 241       return Interfaces.C.int is (Interfaces.C.int (Prio));
 242    --  Maps System.Any_Priority to a POSIX priority
 243
 244    -------------
 245    -- Process --
 246    -------------
 247
 248    type pid_t is private;
 249
 250    function kill (pid : pid_t; sig : Signal) return int;
 251    pragma Import (C, kill, "kill");
 252
 253    function getpid return pid_t;
 254    pragma Import (C, getpid, "getpid");
 255
 256    -------------
 257    -- Threads --
 258    -------------
 259
 260    type Thread_Body is access
 261      function (arg : System.Address) return System.Address;
 262    pragma Convention (C, Thread_Body);
 263
 264    function Thread_Body_Access is new
 265      Ada.Unchecked_Conversion (System.Address, Thread_Body);
 266
 267    type pthread_t is new unsigned_long;
 268    subtype Thread_Id is pthread_t;
 269
 270    function To_pthread_t is
 271      new Ada.Unchecked_Conversion (unsigned_long, pthread_t);
 272
 273    type pthread_mutex_t      is limited private;
 274    type pthread_cond_t       is limited private;
 275    type pthread_attr_t       is limited private;
 276    type pthread_mutexattr_t  is limited private;
 277    type pthread_condattr_t   is limited private;
 278    type pthread_key_t        is private;
 279
 280    PTHREAD_CREATE_DETACHED : constant := 1;
 281
 282    PTHREAD_SCOPE_PROCESS : constant := 1;
 283    PTHREAD_SCOPE_SYSTEM  : constant := 0;
 284
 285    --  Read/Write lock not supported on Android.
 286
 287    subtype pthread_rwlock_t     is pthread_mutex_t;
 288    subtype pthread_rwlockattr_t is pthread_mutexattr_t;
 289
 290    -----------
 291    -- Stack --
 292    -----------
 293
 294    type stack_t is record
 295       ss_sp    : System.Address;
 296       ss_flags : int;
 297       ss_size  : size_t;
 298    end record;
 299    pragma Convention (C, stack_t);
 300
 301    function sigaltstack
 302      (ss  : not null access stack_t;
 303       oss : access stack_t) return int;
 304    pragma Import (C, sigaltstack, "sigaltstack");
 305
 306    Alternate_Stack : aliased System.Address;
 307    pragma Import (C, Alternate_Stack, "__gnat_alternate_stack");
 308    --  The alternate signal stack for stack overflows
 309
 310    Alternate_Stack_Size : constant := 16 * 1024;
 311    --  This must be in keeping with init.c:__gnat_alternate_stack
 312
 313    Stack_Base_Available : constant Boolean := False;
 314    --  Indicates whether the stack base is available on this target
 315
 316    function Get_Stack_Base (thread : pthread_t)
 317      return Address is (Null_Address);
 318    --  This is a dummy procedure to share some GNULLI files
 319
 320    function Get_Page_Size return int;
 321    pragma Import (C, Get_Page_Size, "_getpagesize");
 322    --  Returns the size of a page
 323
 324    PROT_NONE  : constant := 0;
 325    PROT_READ  : constant := 1;
 326    PROT_WRITE : constant := 2;
 327    PROT_EXEC  : constant := 4;
 328    PROT_ALL   : constant := PROT_READ + PROT_WRITE + PROT_EXEC;
 329    PROT_ON    : constant := PROT_READ;
 330    PROT_OFF   : constant := PROT_ALL;
 331
 332    function mprotect (addr : Address; len : size_t; prot : int) return int;
 333    pragma Import (C, mprotect);
 334
 335    ---------------------------------------
 336    -- Nonstandard Thread Initialization --
 337    ---------------------------------------
 338
 339    procedure pthread_init is null;
 340    --  This is a dummy procedure to share some GNULLI files
 341
 342    -------------------------
 343    -- POSIX.1c  Section 3 --
 344    -------------------------
 345
 346    function sigwait (set : access sigset_t; sig : access Signal) return int;
 347    pragma Import (C, sigwait, "sigwait");
 348
 349    function pthread_kill (thread : pthread_t; sig : Signal) return int;
 350    pragma Import (C, pthread_kill, "pthread_kill");
 351
 352    function pthread_sigmask
 353      (how  : int;
 354       set  : access sigset_t;
 355       oset : access sigset_t) return int;
 356    pragma Import (C, pthread_sigmask, "sigprocmask");
 357    --  pthread_sigmask maybe be broken due to mismatch between sigset_t and
 358    --  kernel_sigset_t, substitute sigprocmask temporarily.  ???
 359    --  pragma Import (C, pthread_sigmask, "pthread_sigmask");
 360
 361    --------------------------
 362    -- POSIX.1c  Section 11 --
 363    --------------------------
 364
 365    function pthread_mutexattr_init
 366      (attr : access pthread_mutexattr_t) return int;
 367    pragma Import (C, pthread_mutexattr_init, "pthread_mutexattr_init");
 368
 369    function pthread_mutexattr_destroy
 370      (attr : access pthread_mutexattr_t) return int;
 371    pragma Import (C, pthread_mutexattr_destroy, "pthread_mutexattr_destroy");
 372
 373    function pthread_mutex_init
 374      (mutex : access pthread_mutex_t;
 375       attr  : access pthread_mutexattr_t) return int;
 376    pragma Import (C, pthread_mutex_init, "pthread_mutex_init");
 377
 378    function pthread_mutex_destroy (mutex : access pthread_mutex_t) return int;
 379    pragma Import (C, pthread_mutex_destroy, "pthread_mutex_destroy");
 380
 381    function pthread_mutex_lock (mutex : access pthread_mutex_t) return int;
 382    pragma Import (C, pthread_mutex_lock, "pthread_mutex_lock");
 383
 384    function pthread_mutex_unlock (mutex : access pthread_mutex_t) return int;
 385    pragma Import (C, pthread_mutex_unlock, "pthread_mutex_unlock");
 386
 387    function pthread_condattr_init
 388      (attr : access pthread_condattr_t) return int;
 389    pragma Import (C, pthread_condattr_init, "pthread_condattr_init");
 390
 391    function pthread_condattr_destroy
 392      (attr : access pthread_condattr_t) return int;
 393    pragma Import (C, pthread_condattr_destroy, "pthread_condattr_destroy");
 394
 395    function pthread_cond_init
 396      (cond : access pthread_cond_t;
 397       attr : access pthread_condattr_t) return int;
 398    pragma Import (C, pthread_cond_init, "pthread_cond_init");
 399
 400    function pthread_cond_destroy (cond : access pthread_cond_t) return int;
 401    pragma Import (C, pthread_cond_destroy, "pthread_cond_destroy");
 402
 403    function pthread_cond_signal (cond : access pthread_cond_t) return int;
 404    pragma Import (C, pthread_cond_signal, "pthread_cond_signal");
 405
 406    function pthread_cond_wait
 407      (cond  : access pthread_cond_t;
 408       mutex : access pthread_mutex_t) return int;
 409    pragma Import (C, pthread_cond_wait, "pthread_cond_wait");
 410
 411    function pthread_cond_timedwait
 412      (cond    : access pthread_cond_t;
 413       mutex   : access pthread_mutex_t;
 414       abstime : access timespec) return int;
 415    pragma Import (C, pthread_cond_timedwait, "pthread_cond_timedwait");
 416
 417    Relative_Timed_Wait : constant Boolean := False;
 418    --  pthread_cond_timedwait requires an absolute delay time
 419
 420    --------------------------
 421    -- POSIX.1c  Section 13 --
 422    --------------------------
 423
 424    PTHREAD_PRIO_PROTECT : constant := 0;
 425    PTHREAD_PRIO_INHERIT : constant := 1;
 426
 427    function pthread_mutexattr_setprotocol
 428      (attr     : access pthread_mutexattr_t;
 429       protocol : int) return int is (0);
 430
 431    function pthread_mutexattr_setprioceiling
 432      (attr        : access pthread_mutexattr_t;
 433       prioceiling : int) return int is (0);
 434
 435    type struct_sched_param is record
 436       sched_priority : int;  --  scheduling priority
 437    end record;
 438    pragma Convention (C, struct_sched_param);
 439
 440    function pthread_setschedparam
 441      (thread : pthread_t;
 442       policy : int;
 443       param  : access struct_sched_param) return int;
 444    pragma Import (C, pthread_setschedparam, "pthread_setschedparam");
 445
 446    function pthread_attr_setscope
 447      (attr  : access pthread_attr_t;
 448       scope : int) return int;
 449    pragma Import (C, pthread_attr_setscope, "pthread_attr_setscope");
 450
 451    function pthread_attr_setschedpolicy
 452      (attr   : access pthread_attr_t;
 453       policy : int) return int;
 454    pragma Import
 455      (C, pthread_attr_setschedpolicy, "pthread_attr_setschedpolicy");
 456
 457    function sched_yield return int;
 458    pragma Import (C, sched_yield, "sched_yield");
 459
 460    ---------------------------
 461    -- P1003.1c - Section 16 --
 462    ---------------------------
 463
 464    function pthread_attr_init
 465      (attributes : access pthread_attr_t) return int;
 466    pragma Import (C, pthread_attr_init, "pthread_attr_init");
 467
 468    function pthread_attr_destroy
 469      (attributes : access pthread_attr_t) return int;
 470    pragma Import (C, pthread_attr_destroy, "pthread_attr_destroy");
 471
 472    function pthread_attr_setdetachstate
 473      (attr        : access pthread_attr_t;
 474       detachstate : int) return int;
 475    pragma Import
 476      (C, pthread_attr_setdetachstate, "pthread_attr_setdetachstate");
 477
 478    function pthread_attr_setstacksize
 479      (attr      : access pthread_attr_t;
 480       stacksize : size_t) return int;
 481    pragma Import (C, pthread_attr_setstacksize, "pthread_attr_setstacksize");
 482
 483    function pthread_create
 484      (thread        : access pthread_t;
 485       attributes    : access pthread_attr_t;
 486       start_routine : Thread_Body;
 487       arg           : System.Address) return int;
 488    pragma Import (C, pthread_create, "pthread_create");
 489
 490    procedure pthread_exit (status : System.Address);
 491    pragma Import (C, pthread_exit, "pthread_exit");
 492
 493    function pthread_self return pthread_t;
 494    pragma Import (C, pthread_self, "pthread_self");
 495
 496    function lwp_self return System.Address;
 497    pragma Import (C, lwp_self, "__gnat_lwp_self");
 498
 499    --------------------------
 500    -- POSIX.1c  Section 17 --
 501    --------------------------
 502
 503    function pthread_setspecific
 504      (key   : pthread_key_t;
 505       value : System.Address) return int;
 506    pragma Import (C, pthread_setspecific, "pthread_setspecific");
 507
 508    function pthread_getspecific (key : pthread_key_t) return System.Address;
 509    pragma Import (C, pthread_getspecific, "pthread_getspecific");
 510
 511    type destructor_pointer is access procedure (arg : System.Address);
 512    pragma Convention (C, destructor_pointer);
 513
 514    function pthread_key_create
 515      (key        : access pthread_key_t;
 516       destructor : destructor_pointer) return int;
 517    pragma Import (C, pthread_key_create, "pthread_key_create");
 518
 519    CPU_SETSIZE : constant := 1_024;
 520    --  Size of the cpu_set_t mask on most linux systems (SUSE 11 uses 4_096).
 521    --  This is kept for backward compatibility (System.Task_Info uses it), but
 522    --  the run-time library does no longer rely on static masks, using
 523    --  dynamically allocated masks instead.
 524
 525    type bit_field is array (1 .. CPU_SETSIZE) of Boolean;
 526    for bit_field'Size use CPU_SETSIZE;
 527    pragma Pack (bit_field);
 528    pragma Convention (C, bit_field);
 529
 530    type cpu_set_t is record
 531       bits : bit_field;
 532    end record;
 533    pragma Convention (C, cpu_set_t);
 534
 535    type cpu_set_t_ptr is access all cpu_set_t;
 536    --  In the run-time library we use this pointer because the size of type
 537    --  cpu_set_t varies depending on the glibc version. Hence, objects of type
 538    --  cpu_set_t are allocated dynamically using the number of processors
 539    --  available in the target machine (value obtained at execution time).
 540
 541    function CPU_ALLOC (count : size_t) return cpu_set_t_ptr;
 542    pragma Import (C, CPU_ALLOC, "__gnat_cpu_alloc");
 543    --  Wrapper around the CPU_ALLOC C macro
 544
 545    function CPU_ALLOC_SIZE (count : size_t) return size_t;
 546    pragma Import (C, CPU_ALLOC_SIZE, "__gnat_cpu_alloc_size");
 547    --  Wrapper around the CPU_ALLOC_SIZE C macro
 548
 549    procedure CPU_FREE (cpuset : cpu_set_t_ptr);
 550    pragma Import (C, CPU_FREE, "__gnat_cpu_free");
 551    --  Wrapper around the CPU_FREE C macro
 552
 553    procedure CPU_ZERO (count : size_t; cpuset : cpu_set_t_ptr);
 554    pragma Import (C, CPU_ZERO, "__gnat_cpu_zero");
 555    --  Wrapper around the CPU_ZERO_S C macro
 556
 557    procedure CPU_SET (cpu : int; count : size_t; cpuset : cpu_set_t_ptr);
 558    pragma Import (C, CPU_SET, "__gnat_cpu_set");
 559    --  Wrapper around the CPU_SET_S C macro
 560
 561    function pthread_setaffinity_np
 562      (thread     : pthread_t;
 563       cpusetsize : size_t;
 564       cpuset     : cpu_set_t_ptr) return int;
 565    pragma Import (C, pthread_setaffinity_np, "pthread_setaffinity_np");
 566    pragma Weak_External (pthread_setaffinity_np);
 567    --  Use a weak symbol because this function may be available or not,
 568    --  depending on the version of the system.
 569
 570    function pthread_attr_setaffinity_np
 571      (attr       : access pthread_attr_t;
 572       cpusetsize : size_t;
 573       cpuset     : cpu_set_t_ptr) return int;
 574    pragma Import (C, pthread_attr_setaffinity_np,
 575                     "pthread_attr_setaffinity_np");
 576    pragma Weak_External (pthread_attr_setaffinity_np);
 577    --  Use a weak symbol because this function may be available or not,
 578    --  depending on the version of the system.
 579
 580 private
 581
 582    type sigset_t is new Interfaces.C.unsigned_long;
 583    pragma Convention (C, sigset_t);
 584    for sigset_t'Alignment use Interfaces.C.unsigned_long'Alignment;
 585
 586    pragma Warnings (Off);
 587    for struct_sigaction use record
 588       sa_handler at Linux.sa_handler_pos range 0 .. Standard'Address_Size - 1;
 589       sa_mask    at Linux.sa_mask_pos range 0 .. sigset_t'Size - 1;
 590       sa_flags   at Linux.sa_flags_pos
 591         range 0 .. Interfaces.C.unsigned_long'Size - 1;
 592    end record;
 593    --  We intentionally leave sa_restorer unspecified and let the compiler
 594    --  append it after the last field, so disable corresponding warning.
 595    pragma Warnings (On);
 596
 597    type pid_t is new int;
 598
 599    type time_t is new long;
 600
 601    type timespec is record
 602       tv_sec  : time_t;
 603       tv_nsec : long;
 604    end record;
 605    pragma Convention (C, timespec);
 606
 607    type unsigned_long_long_t is mod 2 ** 64;
 608    --  Local type only used to get the alignment of this type below
 609
 610    subtype char_array is Interfaces.C.char_array;
 611
 612    type pthread_attr_t is record
 613       Data : char_array (1 .. OS_Constants.PTHREAD_ATTR_SIZE);
 614    end record;
 615    pragma Convention (C, pthread_attr_t);
 616    for pthread_attr_t'Alignment use Interfaces.C.unsigned_long'Alignment;
 617
 618    type pthread_condattr_t is record
 619       Data : char_array (1 .. OS_Constants.PTHREAD_CONDATTR_SIZE);
 620    end record;
 621    pragma Convention (C, pthread_condattr_t);
 622    for pthread_condattr_t'Alignment use Interfaces.C.int'Alignment;
 623
 624    type pthread_mutexattr_t is record
 625       Data : char_array (1 .. OS_Constants.PTHREAD_MUTEXATTR_SIZE);
 626    end  record;
 627    pragma Convention (C, pthread_mutexattr_t);
 628    for pthread_mutexattr_t'Alignment use Interfaces.C.int'Alignment;
 629
 630    type pthread_mutex_t is record
 631       Data : char_array (1 .. OS_Constants.PTHREAD_MUTEX_SIZE);
 632    end record;
 633    pragma Convention (C, pthread_mutex_t);
 634    for pthread_mutex_t'Alignment use Interfaces.C.unsigned_long'Alignment;
 635
 636    type pthread_cond_t is record
 637       Data : char_array (1 .. OS_Constants.PTHREAD_COND_SIZE);
 638    end record;
 639    pragma Convention (C, pthread_cond_t);
 640    for pthread_cond_t'Alignment use unsigned_long_long_t'Alignment;
 641
 642    type pthread_key_t is new unsigned;
 643
 644 end System.OS_Interface;