sysdeps/nptl/internaltypes.h

   1 /* Copyright (C) 2002-2018 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _INTERNALTYPES_H
  20 #define _INTERNALTYPES_H        1
  21
  22 #include <stdint.h>
  23 #include <atomic.h>
  24 #include <endian.h>
  25
  26
  27 struct pthread_attr
  28 {
  29   /* Scheduler parameters and priority.  */
  30   struct sched_param schedparam;
  31   int schedpolicy;
  32   /* Various flags like detachstate, scope, etc.  */
  33   int flags;
  34   /* Size of guard area.  */
  35   size_t guardsize;
  36   /* Stack handling.  */
  37   void *stackaddr;
  38   size_t stacksize;
  39   /* Affinity map.  */
  40   cpu_set_t *cpuset;
  41   size_t cpusetsize;
  42 };
  43
  44 #define ATTR_FLAG_DETACHSTATE           0x0001
  45 #define ATTR_FLAG_NOTINHERITSCHED       0x0002
  46 #define ATTR_FLAG_SCOPEPROCESS          0x0004
  47 #define ATTR_FLAG_STACKADDR             0x0008
  48 #define ATTR_FLAG_OLDATTR               0x0010
  49 #define ATTR_FLAG_SCHED_SET             0x0020
  50 #define ATTR_FLAG_POLICY_SET            0x0040
  51
  52
  53 /* Mutex attribute data structure.  */
  54 struct pthread_mutexattr
  55 {
  56   /* Identifier for the kind of mutex.
  57
  58      Bit 31 is set if the mutex is to be shared between processes.
  59
  60      Bit 0 to 30 contain one of the PTHREAD_MUTEX_ values to identify
  61      the type of the mutex.  */
  62   int mutexkind;
  63 };
  64
  65
  66 /* Conditional variable attribute data structure.  */
  67 struct pthread_condattr
  68 {
  69   /* Combination of values:
  70
  71      Bit 0                : flag whether conditional variable will be
  72                             sharable between processes.
  73      Bit 1-COND_CLOCK_BITS: Clock ID.  COND_CLOCK_BITS is the number of bits
  74                             needed to represent the ID of the clock.  */
  75   int value;
  76 };
  77 #define COND_CLOCK_BITS 1
  78
  79
  80 /* Read-write lock variable attribute data structure.  */
  81 struct pthread_rwlockattr
  82 {
  83   int lockkind;
  84   int pshared;
  85 };
  86
  87
  88 /* Barrier data structure.  See pthread_barrier_wait for a description
  89    of how these fields are used.  */
  90 struct pthread_barrier
  91 {
  92   unsigned int in;
  93   unsigned int current_round;
  94   unsigned int count;
  95   int shared;
  96   unsigned int out;
  97 };
  98 /* See pthread_barrier_wait for a description.  */
  99 #define BARRIER_IN_THRESHOLD (UINT_MAX/2)
 100
 101
 102 /* Barrier variable attribute data structure.  */
 103 struct pthread_barrierattr
 104 {
 105   int pshared;
 106 };
 107
 108
 109 /* Thread-local data handling.  */
 110 struct pthread_key_struct
 111 {
 112   /* Sequence numbers.  Even numbers indicated vacant entries.  Note
 113      that zero is even.  We use uintptr_t to not require padding on
 114      32- and 64-bit machines.  On 64-bit machines it helps to avoid
 115      wrapping, too.  */
 116   uintptr_t seq;
 117
 118   /* Destructor for the data.  */
 119   void (*destr) (void *);
 120 };
 121
 122 /* Check whether an entry is unused.  */
 123 #define KEY_UNUSED(p) (((p) & 1) == 0)
 124 /* Check whether a key is usable.  We cannot reuse an allocated key if
 125    the sequence counter would overflow after the next destroy call.
 126    This would mean that we potentially free memory for a key with the
 127    same sequence.  This is *very* unlikely to happen, A program would
 128    have to create and destroy a key 2^31 times (on 32-bit platforms,
 129    on 64-bit platforms that would be 2^63).  If it should happen we
 130    simply don't use this specific key anymore.  */
 131 #define KEY_USABLE(p) (((uintptr_t) (p)) < ((uintptr_t) ((p) + 2)))
 132
 133
 134 /* Handling of read-write lock data.  */
 135 // XXX For now there is only one flag.  Maybe more in future.
 136 #define RWLOCK_RECURSIVE(rwlock) ((rwlock)->__data.__flags != 0)
 137
 138
 139 /* Semaphore variable structure.  */
 140 struct new_sem
 141 {
 142 #if __HAVE_64B_ATOMICS
 143   /* The data field holds both value (in the least-significant 32 bits) and
 144      nwaiters.  */
 145 # if __BYTE_ORDER == __LITTLE_ENDIAN
 146 #  define SEM_VALUE_OFFSET 0
 147 # elif __BYTE_ORDER == __BIG_ENDIAN
 148 #  define SEM_VALUE_OFFSET 1
 149 # else
 150 # error Unsupported byte order.
 151 # endif
 152 # define SEM_NWAITERS_SHIFT 32
 153 # define SEM_VALUE_MASK (~(unsigned int)0)
 154   uint64_t data;
 155   int private;
 156   int pad;
 157 #else
 158 # define SEM_VALUE_SHIFT 1
 159 # define SEM_NWAITERS_MASK ((unsigned int)1)
 160   unsigned int value;
 161   int private;
 162   int pad;
 163   unsigned int nwaiters;
 164 #endif
 165 };
 166
 167 struct old_sem
 168 {
 169   unsigned int value;
 170 };
 171
 172
 173 /* Compatibility type for old conditional variable interfaces.  */
 174 typedef struct
 175 {
 176   pthread_cond_t *cond;
 177 } pthread_cond_2_0_t;
 178
 179 #endif  /* internaltypes.h */