sysdeps/nptl/internaltypes.h

   1 /* Copyright (C) 2002-2015 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 sharable between
  72               processes.
  73
  74      Bit 1-7: clock ID.  */
  75   int value;
  76 };
  77
  78
  79 /* The __NWAITERS field is used as a counter and to house the number
  80    of bits for other purposes.  COND_CLOCK_BITS is the number
  81    of bits needed to represent the ID of the clock.  COND_NWAITERS_SHIFT
  82    is the number of bits reserved for other purposes like the clock.  */
  83 #define COND_CLOCK_BITS         1
  84 #define COND_NWAITERS_SHIFT     1
  85
  86
  87 /* Read-write lock variable attribute data structure.  */
  88 struct pthread_rwlockattr
  89 {
  90   int lockkind;
  91   int pshared;
  92 };
  93
  94
  95 /* Barrier data structure.  */
  96 struct pthread_barrier
  97 {
  98   unsigned int curr_event;
  99   int lock;
 100   unsigned int left;
 101   unsigned int init_count;
 102   int private;
 103 };
 104
 105
 106 /* Barrier variable attribute data structure.  */
 107 struct pthread_barrierattr
 108 {
 109   int pshared;
 110 };
 111
 112
 113 /* Thread-local data handling.  */
 114 struct pthread_key_struct
 115 {
 116   /* Sequence numbers.  Even numbers indicated vacant entries.  Note
 117      that zero is even.  We use uintptr_t to not require padding on
 118      32- and 64-bit machines.  On 64-bit machines it helps to avoid
 119      wrapping, too.  */
 120   uintptr_t seq;
 121
 122   /* Destructor for the data.  */
 123   void (*destr) (void *);
 124 };
 125
 126 /* Check whether an entry is unused.  */
 127 #define KEY_UNUSED(p) (((p) & 1) == 0)
 128 /* Check whether a key is usable.  We cannot reuse an allocated key if
 129    the sequence counter would overflow after the next destroy call.
 130    This would mean that we potentially free memory for a key with the
 131    same sequence.  This is *very* unlikely to happen, A program would
 132    have to create and destroy a key 2^31 times (on 32-bit platforms,
 133    on 64-bit platforms that would be 2^63).  If it should happen we
 134    simply don't use this specific key anymore.  */
 135 #define KEY_USABLE(p) (((uintptr_t) (p)) < ((uintptr_t) ((p) + 2)))
 136
 137
 138 /* Handling of read-write lock data.  */
 139 // XXX For now there is only one flag.  Maybe more in future.
 140 #define RWLOCK_RECURSIVE(rwlock) ((rwlock)->__data.__flags != 0)
 141
 142
 143 /* Semaphore variable structure.  */
 144 struct new_sem
 145 {
 146 #if __HAVE_64B_ATOMICS
 147   /* The data field holds both value (in the least-significant 32 bytes) and
 148      nwaiters.  */
 149 # if __BYTE_ORDER == __LITTLE_ENDIAN
 150 #  define SEM_VALUE_OFFSET 0
 151 # elif __BYTE_ORDER == __BIG_ENDIAN
 152 #  define SEM_VALUE_OFFSET 1
 153 # else
 154 # error Unsupported byte order.
 155 # endif
 156 # define SEM_NWAITERS_SHIFT 32
 157 # define SEM_VALUE_MASK (~(unsigned int)0)
 158   uint64_t data;
 159   int private;
 160   int pad;
 161 #else
 162 # define SEM_VALUE_SHIFT 1
 163 # define SEM_NWAITERS_MASK ((unsigned int)1)
 164   unsigned int value;
 165   int private;
 166   int pad;
 167   unsigned int nwaiters;
 168 #endif
 169 };
 170
 171 struct old_sem
 172 {
 173   unsigned int value;
 174 };
 175
 176
 177 /* Compatibility type for old conditional variable interfaces.  */
 178 typedef struct
 179 {
 180   pthread_cond_t *cond;
 181 } pthread_cond_2_0_t;
 182
 183 #endif  /* internaltypes.h */