utils.h

   1 /*
   2  * Copyright 2004 Timo Hirvonen
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  17  * 02111-1307, USA.
  18  */
  19
  20 #ifndef _UTILS_H
  21 #define _UTILS_H
  22
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <sys/types.h>
  26 #include <sys/stat.h>
  27 #include <unistd.h>
  28 #include <time.h>
  29
  30 static inline int min(int a, int b)
  31 {
  32         return a < b ? a : b;
  33 }
  34
  35 static inline int max(int a, int b)
  36 {
  37         return a > b ? a : b;
  38 }
  39
  40 static inline int clamp(int val, int minval, int maxval)
  41 {
  42         if (val < minval)
  43                 return minval;
  44         if (val > maxval)
  45                 return maxval;
  46         return val;
  47 }
  48
  49 static inline int scale_from_percentage(int val, int max_val)
  50 {
  51         if (val < 0)
  52                 return (val * max_val - 50) / 100;
  53         return (val * max_val + 50) / 100;
  54 }
  55
  56 static inline int scale_to_percentage(int val, int max_val)
  57 {
  58         int half = max_val / 2;
  59
  60         if (max_val <= 0)
  61                 return 100;
  62
  63         if (val < 0)
  64                 return (val * 100 - half) / max_val;
  65         return (val * 100 + half) / max_val;
  66 }
  67
  68 static inline int str_to_int(const char *str, long int *val)
  69 {
  70         char *end;
  71
  72         *val = strtol(str, &end, 10);
  73         if (*str == 0 || *end != 0)
  74                 return -1;
  75         return 0;
  76 }
  77
  78 static inline time_t file_get_mtime(const char *filename)
  79 {
  80         struct stat s;
  81
  82         /* stat follows symlinks, lstat does not */
  83         if (stat(filename, &s) == -1)
  84                 return -1;
  85         return s.st_mtime;
  86 }
  87
  88 static inline void ns_sleep(int ns)
  89 {
  90         struct timespec req;
  91
  92         req.tv_sec = 0;
  93         req.tv_nsec = ns;
  94         nanosleep(&req, NULL);
  95 }
  96
  97 static inline void us_sleep(int us)
  98 {
  99         ns_sleep(us * 1e3);
 100 }
 101
 102 static inline void ms_sleep(int ms)
 103 {
 104         ns_sleep(ms * 1e6);
 105 }
 106
 107 static inline int is_url(const char *name)
 108 {
 109         return strncmp(name, "http://", 7) == 0;
 110 }
 111
 112 #endif