minix/servers/pm/time.c

   1 /* This file takes care of those system calls that deal with time.
   2  *
   3  * The entry points into this file are
   4  *   do_getres:         perform the CLOCK_GETRES system call
   5  *   do_gettime:        perform the CLOCK_GETTIME system call
   6  *   do_settime:        perform the CLOCK_SETTIME system call
   7  *   do_time:           perform the GETTIMEOFDAY system call
   8  *   do_stime:          perform the STIME system call
   9  */
  10
  11 #include "pm.h"
  12 #include <minix/callnr.h>
  13 #include <minix/com.h>
  14 #include <signal.h>
  15 #include <sys/time.h>
  16 #include "mproc.h"
  17
  18 /*===========================================================================*
  19  *                              do_gettime                                   *
  20  *===========================================================================*/
  21 int
  22 do_gettime(void)
  23 {
  24   clock_t ticks, realtime, clock;
  25   time_t boottime;
  26   int s;
  27
  28   if ( (s=getuptime(&ticks, &realtime, &boottime)) != OK)
  29         panic("do_time couldn't get uptime: %d", s);
  30
  31   switch (m_in.m_lc_pm_time.clk_id) {
  32         case CLOCK_REALTIME:
  33                 clock = realtime;
  34                 break;
  35         case CLOCK_MONOTONIC:
  36                 clock = ticks;
  37                 break;
  38         default:
  39                 return EINVAL; /* invalid/unsupported clock_id */
  40   }
  41
  42   mp->mp_reply.m_pm_lc_time.sec = boottime + (clock / system_hz);
  43   mp->mp_reply.m_pm_lc_time.nsec =
  44         (uint32_t) ((clock % system_hz) * 1000000000ULL / system_hz);
  45
  46   return(OK);
  47 }
  48
  49 /*===========================================================================*
  50  *                              do_getres                                    *
  51  *===========================================================================*/
  52 int
  53 do_getres(void)
  54 {
  55   switch (m_in.m_lc_pm_time.clk_id) {
  56         case CLOCK_REALTIME:
  57         case CLOCK_MONOTONIC:
  58                 /* tv_sec is always 0 since system_hz is an int */
  59                 mp->mp_reply.m_pm_lc_time.sec = 0;
  60                 mp->mp_reply.m_pm_lc_time.nsec = 1000000000 / system_hz;
  61                 return(OK);
  62         default:
  63                 return EINVAL; /* invalid/unsupported clock_id */
  64   }
  65 }
  66
  67 /*===========================================================================*
  68  *                              do_settime                                   *
  69  *===========================================================================*/
  70 int
  71 do_settime(void)
  72 {
  73   int s;
  74
  75   if (mp->mp_effuid != SUPER_USER) {
  76       return(EPERM);
  77   }
  78
  79   switch (m_in.m_lc_pm_time.clk_id) {
  80         case CLOCK_REALTIME:
  81                 s = sys_settime(m_in.m_lc_pm_time.now, m_in.m_lc_pm_time.clk_id,
  82                         m_in.m_lc_pm_time.sec, m_in.m_lc_pm_time.nsec);
  83                 return(s);
  84         case CLOCK_MONOTONIC: /* monotonic cannot be changed */
  85         default:
  86                 return EINVAL; /* invalid/unsupported clock_id */
  87   }
  88 }
  89
  90 /*===========================================================================*
  91  *                              do_time                                      *
  92  *===========================================================================*/
  93 int
  94 do_time(void)
  95 {
  96 /* Perform the time(tp) system call. */
  97   struct timespec tv;
  98
  99   (void)clock_time(&tv);
 100
 101   mp->mp_reply.m_pm_lc_time.sec = tv.tv_sec;
 102   mp->mp_reply.m_pm_lc_time.nsec = tv.tv_nsec;
 103   return(OK);
 104 }
 105
 106 /*===========================================================================*
 107  *                              do_stime                                     *
 108  *===========================================================================*/
 109 int
 110 do_stime(void)
 111 {
 112 /* Perform the stime(tp) system call. Retrieve the system's uptime (ticks
 113  * since boot) and pass the new time in seconds at system boot to the kernel.
 114  */
 115   clock_t uptime, realtime;
 116   time_t boottime;
 117   int s;
 118
 119   if (mp->mp_effuid != SUPER_USER) {
 120       return(EPERM);
 121   }
 122   if ( (s=getuptime(&uptime, &realtime, &boottime)) != OK)
 123       panic("do_stime couldn't get uptime: %d", s);
 124   boottime = m_in.m_lc_pm_time.sec - (realtime/system_hz);
 125
 126   s= sys_stime(boottime);               /* Tell kernel about boottime */
 127   if (s != OK)
 128         panic("pm: sys_stime failed: %d", s);
 129
 130   return(OK);
 131 }