wmix/misc.c

   1 /* WMix 3.0 -- a mixer using the OSS mixer API.
   2  * Copyright (C) 2000, 2001
   3  *      Daniel Richard G. <skunk@mit.edu>,
   4  *      timecop <timecop@japan.co.jp>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #ifdef HAVE_CONFIG_H
  22 #include "config.h"
  23 #endif
  24
  25 #include <sys/types.h>
  26 #include <stdio.h>
  27 #include <assert.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <unistd.h>
  31 #include <sys/time.h>
  32
  33 #include "include/common.h"
  34 #include "include/misc.h"
  35
  36 typedef struct {
  37     int enable;
  38     int x;
  39     int y;
  40     int width;
  41     int height;
  42 } MRegion;
  43 MRegion mr[16];
  44
  45
  46 /* Converts separate left and right channel volumes (each in [0, 1]) to
  47  * volume and balance values. (Volume is in [0, 1], balance is in [-1, 1])
  48  */
  49 void lr_to_vb(float left, float right, float *volume, float *balance)
  50 {
  51     assert((left >= 0.0) && (right >= 0.0));
  52
  53     *volume = MAX(left, right);
  54
  55     if (left > right)
  56         *balance = -1.0 + right / left;
  57     else if (right > left)
  58         *balance = 1.0 - left / right;
  59     else
  60         *balance = 0.0;
  61 }
  62
  63 /* Performs the reverse calculation of lr_to_vb()
  64  */
  65 void vb_to_lr(float volume, float balance, float *left, float *right)
  66 {
  67 /*    *left = volume; *right = volume; return; // XXX */
  68
  69     *left = volume * (1.0 - MAX(0.0, balance));
  70     *right = volume * (1.0 + MIN(0.0, balance));
  71 }
  72
  73 double get_current_time(void)
  74 {
  75     struct timeval tv;
  76     double t;
  77
  78     gettimeofday(&tv, NULL);
  79
  80     t = (double)tv.tv_sec;
  81     t += (double)tv.tv_usec / 1.0e6;
  82
  83     return t;
  84 }
  85
  86 void add_region(int index, int x, int y, int width, int height)
  87 {
  88     mr[index].enable = 1;
  89     mr[index].x = x;
  90     mr[index].y = y;
  91     mr[index].width = width;
  92     mr[index].height = height;
  93 }
  94
  95 int check_region(int x, int y)
  96 {
  97     register int i;
  98     bool found = false;
  99
 100     for (i = 0; i < 16 && !found; i++) {
 101         if (mr[i].enable && x >= mr[i].x &&
 102             x <= mr[i].x + mr[i].width &&
 103             y >= mr[i].y && y <= mr[i].y + mr[i].height)
 104             found = true;
 105     }
 106     if (!found)
 107         return -1;
 108     return (i - 1);
 109 }
 110
 111 /* handle writing PID file, silently ignore if we can't do it */
 112 void create_pid_file(void)
 113 {
 114     char *home;
 115     char *pid;
 116     FILE *fp;
 117
 118     home = getenv("HOME");
 119     if (home == NULL)
 120         return;
 121
 122     pid = calloc(1, strlen(home) + 10);
 123     sprintf(pid, "%s/.wmix.pid", home);
 124     fp = fopen(pid, "w");
 125     if (fp) {
 126         fprintf(fp, "%d\n", getpid());
 127         fclose(fp);
 128     }
 129     free(pid);
 130 }