sysdeps/mach/hurd/htl/pt-mutex-lock.c

   1 /* pthread_mutex_lock.  Hurd version.
   2    Copyright (C) 2016-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <pthread.h>
  20 #include <stdlib.h>
  21 #include <assert.h>
  22 #include <pt-internal.h>
  23 #include "pt-mutex.h"
  24 #include <hurdlock.h>
  25
  26 int
  27 __pthread_mutex_lock (pthread_mutex_t *mtxp)
  28 {
  29   struct __pthread *self;
  30   int flags = mtxp->__flags & GSYNC_SHARED;
  31   int ret = 0;
  32
  33   switch (MTX_TYPE (mtxp))
  34     {
  35     case PT_MTX_NORMAL:
  36       lll_lock (mtxp->__lock, flags);
  37       break;
  38
  39     case PT_MTX_RECURSIVE:
  40       self = _pthread_self ();
  41       if (mtx_owned_p (mtxp, self, flags))
  42         {
  43           if (__glibc_unlikely (mtxp->__cnt + 1 == 0))
  44             return EAGAIN;
  45
  46           ++mtxp->__cnt;
  47           return ret;
  48         }
  49
  50       lll_lock (mtxp->__lock, flags);
  51       mtx_set_owner (mtxp, self, flags);
  52       mtxp->__cnt = 1;
  53       break;
  54
  55     case PT_MTX_ERRORCHECK:
  56       self = _pthread_self ();
  57       if (mtx_owned_p (mtxp, self, flags))
  58         return EDEADLK;
  59
  60       lll_lock (mtxp->__lock, flags);
  61       mtx_set_owner (mtxp, self, flags);
  62       break;
  63
  64     case PT_MTX_NORMAL | PTHREAD_MUTEX_ROBUST:
  65     case PT_MTX_RECURSIVE | PTHREAD_MUTEX_ROBUST:
  66     case PT_MTX_ERRORCHECK | PTHREAD_MUTEX_ROBUST:
  67       self = _pthread_self ();
  68       ROBUST_LOCK (self, mtxp, lll_robust_lock, flags);
  69       break;
  70
  71     default:
  72       ret = EINVAL;
  73       break;
  74     }
  75
  76   return ret;
  77 }
  78
  79 hidden_def (__pthread_mutex_lock)
  80 strong_alias (__pthread_mutex_lock, _pthread_mutex_lock)
  81 weak_alias (__pthread_mutex_lock, pthread_mutex_lock)