Subversion Repositories HelenOS

Rev

Rev 2677 | Rev 3386 | Go to most recent revision | Blame | Compare with Previous | Last modification | View Log | Download | RSS feed

  1. /*
  2.  * Copyright (c) 2006 Ondrej Palkovsky
  3.  * All rights reserved.
  4.  *
  5.  * Redistribution and use in source and binary forms, with or without
  6.  * modification, are permitted provided that the following conditions
  7.  * are met:
  8.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. /** @addtogroup libc
  30.  * @{
  31.  */
  32. /** @file
  33.  */
  34.  
  35. #include <sys/time.h>
  36. #include <unistd.h>
  37. #include <ipc/ipc.h>
  38. #include <stdio.h>
  39. #include <arch/barrier.h>
  40. #include <unistd.h>
  41. #include <atomic.h>
  42. #include <futex.h>
  43. #include <sysinfo.h>
  44. #include <ipc/services.h>
  45.  
  46. #include <sysinfo.h>
  47. #include <as.h>
  48. #include <ddi.h>
  49.  
  50. /* Pointers to public variables with time */
  51. struct {
  52.     volatile sysarg_t seconds1;
  53.     volatile sysarg_t useconds;
  54.     volatile sysarg_t seconds2;
  55. } *ktime = NULL;
  56.  
  57. /** Add microseconds to given timeval.
  58.  *
  59.  * @param tv        Destination timeval.
  60.  * @param usecs     Number of microseconds to add.
  61.  */
  62. void tv_add(struct timeval *tv, suseconds_t usecs)
  63. {
  64.     tv->tv_sec += usecs / 1000000;
  65.     tv->tv_usec += usecs % 1000000;
  66.     if (tv->tv_usec > 1000000) {
  67.         tv->tv_sec++;
  68.         tv->tv_usec -= 1000000;
  69.     }
  70. }
  71.  
  72. /** Subtract two timevals.
  73.  *
  74.  * @param tv1       First timeval.
  75.  * @param tv2       Second timeval.
  76.  *
  77.  * @return      Return difference between tv1 and tv2 (tv1 - tv2) in
  78.  *          microseconds.
  79.  */
  80. suseconds_t tv_sub(struct timeval *tv1, struct timeval *tv2)
  81. {
  82.     suseconds_t result;
  83.  
  84.     result = tv1->tv_usec - tv2->tv_usec;
  85.     result += (tv1->tv_sec - tv2->tv_sec) * 1000000;
  86.  
  87.     return result;
  88. }
  89.  
  90. /** Decide if one timeval is greater than the other.
  91.  *
  92.  * @param t1        First timeval.
  93.  * @param t2        Second timeval.
  94.  *
  95.  * @return      Return true tv1 is greater than tv2. Otherwise return
  96.  *          false.
  97.  */
  98. int tv_gt(struct timeval *tv1, struct timeval *tv2)
  99. {
  100.     if (tv1->tv_sec > tv2->tv_sec)
  101.         return 1;
  102.     if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec > tv2->tv_usec)
  103.         return 1;
  104.     return 0;
  105. }
  106.  
  107. /** Decide if one timeval is greater than or equal to the other.
  108.  *
  109.  * @param tv1       First timeval.
  110.  * @param tv2       Second timeval.
  111.  *
  112.  * @return      Return true if tv1 is greater than or equal to tv2.
  113.  *          Otherwise return false.
  114.  */
  115. int tv_gteq(struct timeval *tv1, struct timeval *tv2)
  116. {
  117.     if (tv1->tv_sec > tv2->tv_sec)
  118.         return 1;
  119.     if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec >= tv2->tv_usec)
  120.         return 1;
  121.     return 0;
  122. }
  123.  
  124.  
  125. /** POSIX gettimeofday
  126.  *
  127.  * The time variables are memory mapped(RO) from kernel, which updates
  128.  * them periodically. As it is impossible to read 2 values atomically, we
  129.  * use a trick: First read a seconds, then read microseconds, then
  130.  * read seconds again. If a second elapsed in the meantime, set it to zero.
  131.  * This provides assurance, that at least the
  132.  * sequence of subsequent gettimeofday calls is ordered.
  133.  */
  134. int gettimeofday(struct timeval *tv, struct timezone *tz)
  135. {
  136.     void *mapping;
  137.     sysarg_t s1, s2;
  138.     int rights;
  139.     int res;
  140.  
  141.     if (!ktime) {
  142.         mapping = as_get_mappable_page(PAGE_SIZE);
  143.         /* Get the mapping of kernel clock */
  144.         res = ipc_share_in_start_1_1(PHONE_NS, mapping, PAGE_SIZE,
  145.             SERVICE_MEM_REALTIME, &rights);
  146.         if (res) {
  147.             printf("Failed to initialize timeofday memarea\n");
  148.             _exit(1);
  149.         }
  150.         if (!(rights & AS_AREA_READ)) {
  151.             printf("Received bad rights on time area: %X\n",
  152.                 rights);
  153.             as_area_destroy(mapping);
  154.             _exit(1);
  155.         }
  156.         ktime = mapping;
  157.     }
  158.     if (tz) {
  159.         tz->tz_minuteswest = 0;
  160.         tz->tz_dsttime = DST_NONE;
  161.     }
  162.  
  163.     s2 = ktime->seconds2;
  164.     read_barrier();
  165.     tv->tv_usec = ktime->useconds;
  166.     read_barrier();
  167.     s1 = ktime->seconds1;
  168.     if (s1 != s2) {
  169.         tv->tv_usec = 0;
  170.         tv->tv_sec = s1 > s2 ? s1 : s2;
  171.     } else
  172.         tv->tv_sec = s1;
  173.  
  174.     return 0;
  175. }
  176.  
  177. time_t time(time_t *tloc)
  178. {
  179.     struct timeval tv;
  180.  
  181.     if (gettimeofday(&tv, NULL))
  182.         return (time_t) -1;
  183.     if (tloc)
  184.         *tloc = tv.tv_sec;
  185.     return tv.tv_sec;
  186. }
  187.  
  188. /** Wait unconditionally for specified number of microseconds */
  189. int usleep(unsigned long usec)
  190. {
  191.     atomic_t futex = FUTEX_INITIALIZER;
  192.  
  193.     futex_initialize(&futex, 0);
  194.     futex_down_timeout(&futex, usec, 0);
  195.     return 0;
  196. }
  197.  
  198. /** Wait unconditionally for specified number of seconds */
  199. unsigned int sleep(unsigned int seconds)
  200. {
  201.     atomic_t futex = FUTEX_INITIALIZER;
  202.  
  203.     futex_initialize(&futex, 0);
  204.    
  205.     /* Sleep in 1000 second steps to support
  206.        full argument range */
  207.     while (seconds > 0) {
  208.         unsigned int period = (seconds > 1000) ? 1000 : seconds;
  209.    
  210.         futex_down_timeout(&futex, period * 1000000, 0);
  211.         seconds -= period;
  212.     }
  213.     return 0;
  214. }
  215.  
  216. /** @}
  217.  */
  218.