1/*
2 * pthreads_delay_np.c
3 *
4 * Description:
5 * This translation unit implements non-portable thread functions.
6 *
7 * --------------------------------------------------------------------------
8 *
9 *      Pthreads-win32 - POSIX Threads Library for Win32
10 *      Copyright(C) 1998 John E. Bossom
11 *      Copyright(C) 1999,2005 Pthreads-win32 contributors
12 *
13 *      Contact Email: rpj@callisto.canberra.edu.au
14 *
15 *      The current list of contributors is contained
16 *      in the file CONTRIBUTORS included with the source
17 *      code distribution. The list can also be seen at the
18 *      following World Wide Web location:
19 *      http://sources.redhat.com/pthreads-win32/contributors.html
20 *
21 *      This library is free software; you can redistribute it and/or
22 *      modify it under the terms of the GNU Lesser General Public
23 *      License as published by the Free Software Foundation; either
24 *      version 2 of the License, or (at your option) any later version.
25 *
26 *      This library is distributed in the hope that it will be useful,
27 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
28 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
29 *      Lesser General Public License for more details.
30 *
31 *      You should have received a copy of the GNU Lesser General Public
32 *      License along with this library in the file COPYING.LIB;
33 *      if not, write to the Free Software Foundation, Inc.,
34 *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
35 */
36
37#include "pthread.h"
38#include "implement.h"
39
40/*
41 * pthread_delay_np
42 *
43 * DESCRIPTION
44 *
45 *       This routine causes a thread to delay execution for a specific period of time.
46 *       This period ends at the current time plus the specified interval. The routine
47 *       will not return before the end of the period is reached, but may return an
48 *       arbitrary amount of time after the period has gone by. This can be due to
49 *       system load, thread priorities, and system timer granularity.
50 *
51 *       Specifying an interval of zero (0) seconds and zero (0) nanoseconds is
52 *       allowed and can be used to force the thread to give up the processor or to
53 *       deliver a pending cancelation request.
54 *
55 *       The timespec structure contains the following two fields:
56 *
57 *            tv_sec is an integer number of seconds.
58 *            tv_nsec is an integer number of nanoseconds.
59 *
60 *  Return Values
61 *
62 *  If an error condition occurs, this routine returns an integer value indicating
63 *  the type of error. Possible return values are as follows:
64 *
65 *  0
66 *           Successful completion.
67 *  [EINVAL]
68 *           The value specified by interval is invalid.
69 *
70 * Example
71 *
72 * The following code segment would wait for 5 and 1/2 seconds
73 *
74 *  struct timespec tsWait;
75 *  int      intRC;
76 *
77 *  tsWait.tv_sec  = 5;
78 *  tsWait.tv_nsec = 500000000L;
79 *  intRC = pthread_delay_np(&tsWait);
80 */
81int
82pthread_delay_np (struct timespec *interval)
83{
84  DWORD wait_time;
85  DWORD secs_in_millisecs;
86  DWORD millisecs;
87  DWORD status;
88  pthread_t self;
89  ptw32_thread_t * sp;
90
91  if (interval == NULL)
92    {
93      return EINVAL;
94    }
95
96  if (interval->tv_sec == 0L && interval->tv_nsec == 0L)
97    {
98      pthread_testcancel ();
99      Sleep (0);
100      pthread_testcancel ();
101      return (0);
102    }
103
104  /* convert secs to millisecs */
105  secs_in_millisecs = (DWORD)interval->tv_sec * 1000L;
106
107  /* convert nanosecs to millisecs (rounding up) */
108  millisecs = (interval->tv_nsec + 999999L) / 1000000L;
109
110#if defined(__WATCOMC__)
111#pragma disable_message (124)
112#endif
113
114  /*
115   * Most compilers will issue a warning 'comparison always 0'
116   * because the variable type is unsigned, but we need to keep this
117   * for some reason I can't recall now.
118   */
119  if (0 > (wait_time = secs_in_millisecs + millisecs))
120    {
121      return EINVAL;
122    }
123
124#if defined(__WATCOMC__)
125#pragma enable_message (124)
126#endif
127
128  if (NULL == (self = pthread_self ()).p)
129    {
130      return ENOMEM;
131    }
132
133  sp = (ptw32_thread_t *) self.p;
134
135  if (sp->cancelState == PTHREAD_CANCEL_ENABLE)
136    {
137      /*
138       * Async cancelation won't catch us until wait_time is up.
139       * Deferred cancelation will cancel us immediately.
140       */
141      if (WAIT_OBJECT_0 ==
142	  (status = WaitForSingleObject (sp->cancelEvent, wait_time)))
143	{
144          ptw32_mcs_local_node_t stateLock;
145	  /*
146	   * Canceling!
147	   */
148	  ptw32_mcs_lock_acquire (&sp->stateLock, &stateLock);
149	  if (sp->state < PThreadStateCanceling)
150	    {
151	      sp->state = PThreadStateCanceling;
152	      sp->cancelState = PTHREAD_CANCEL_DISABLE;
153	      ptw32_mcs_lock_release (&stateLock);
154
155	      ptw32_throw (PTW32_EPS_CANCEL);
156	    }
157
158	  ptw32_mcs_lock_release (&stateLock);
159	  return ESRCH;
160	}
161      else if (status != WAIT_TIMEOUT)
162	{
163	  return EINVAL;
164	}
165    }
166  else
167    {
168      Sleep (wait_time);
169    }
170
171  return (0);
172}
173