source4/lib/events/events_util.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Copyright (C) Andrew Tridgell 2005
   5    Copyright (C) Jelmer Vernooij 2005
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "replace.h"
  22 #include "talloc.h"
  23
  24 /**
  25   return the number of elements in a string list
  26 */
  27 static size_t str_list_length(const char **list)
  28 {
  29         size_t ret;
  30         for (ret=0;list && list[ret];ret++) /* noop */ ;
  31         return ret;
  32 }
  33
  34 /**
  35   add an entry to a string list
  36 */
  37 const char **str_list_add(const char **list, const char *s)
  38 {
  39         size_t len = str_list_length(list);
  40         const char **ret;
  41
  42         ret = talloc_realloc(NULL, list, const char *, len+2);
  43         if (ret == NULL) return NULL;
  44
  45         ret[len] = talloc_strdup(ret, s);
  46         if (ret[len] == NULL) return NULL;
  47
  48         ret[len+1] = NULL;
  49
  50         return ret;
  51 }
  52
  53 /**
  54   compare two timeval structures.
  55   Return -1 if tv1 < tv2
  56   Return 0 if tv1 == tv2
  57   Return 1 if tv1 > tv2
  58 */
  59 static int timeval_compare(const struct timeval *tv1, const struct timeval *tv2)
  60 {
  61         if (tv1->tv_sec  > tv2->tv_sec)  return 1;
  62         if (tv1->tv_sec  < tv2->tv_sec)  return -1;
  63         if (tv1->tv_usec > tv2->tv_usec) return 1;
  64         if (tv1->tv_usec < tv2->tv_usec) return -1;
  65         return 0;
  66 }
  67
  68 /**
  69   return a zero timeval
  70 */
  71 struct timeval timeval_zero(void)
  72 {
  73         struct timeval tv;
  74         tv.tv_sec = 0;
  75         tv.tv_usec = 0;
  76         return tv;
  77 }
  78
  79 /**
  80   return true if a timeval is zero
  81 */
  82 bool timeval_is_zero(const struct timeval *tv)
  83 {
  84         return tv->tv_sec == 0 && tv->tv_usec == 0;
  85 }
  86
  87 /**
  88   return a timeval for the current time
  89 */
  90 struct timeval timeval_current(void)
  91 {
  92         struct timeval tv;
  93         GetTimeOfDay(&tv);
  94         return tv;
  95 }
  96
  97 /**
  98   return a timeval struct with the given elements
  99 */
 100 struct timeval timeval_set(uint32_t secs, uint32_t usecs)
 101 {
 102         struct timeval tv;
 103         tv.tv_sec = secs;
 104         tv.tv_usec = usecs;
 105         return tv;
 106 }
 107
 108 /**
 109   return the difference between two timevals as a timeval
 110   if tv1 comes after tv2, then return a zero timeval
 111   (this is *tv2 - *tv1)
 112 */
 113 struct timeval timeval_until(const struct timeval *tv1,
 114                              const struct timeval *tv2)
 115 {
 116         struct timeval t;
 117         if (timeval_compare(tv1, tv2) >= 0) {
 118                 return timeval_zero();
 119         }
 120         t.tv_sec = tv2->tv_sec - tv1->tv_sec;
 121         if (tv1->tv_usec > tv2->tv_usec) {
 122                 t.tv_sec--;
 123                 t.tv_usec = 1000000 - (tv1->tv_usec - tv2->tv_usec);
 124         } else {
 125                 t.tv_usec = tv2->tv_usec - tv1->tv_usec;
 126         }
 127         return t;
 128 }
 129