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 /* Converts separate left and right channel volumes (each in [0, 1]) to
  46  * volume and balance values. (Volume is in [0, 1], balance is in [-1, 1])
  47  */
  48 void lr_to_vb(float left, float right, float *volume, float *balance)
  49 {
  50     assert((left >= 0.0) && (right >= 0.0));
  51
  52     *volume = MAX(left, right);
  53
  54     if (left > right)
  55         *balance = -1.0 + right / left;
  56     else if (right > left)
  57         *balance = 1.0 - left / right;
  58     else
  59         *balance = 0.0;
  60 }
  61
  62 /* Performs the reverse calculation of lr_to_vb()
  63  */
  64 void vb_to_lr(float volume, float balance, float *left, float *right)
  65 {
  66 /*    *left = volume; *right = volume; return; // XXX */
  67
  68     *left = volume * (1.0 - MAX(0.0, balance));
  69     *right = volume * (1.0 + MIN(0.0, balance));
  70 }
  71
  72 double get_current_time(void)
  73 {
  74     struct timeval tv;
  75     double t;
  76
  77     gettimeofday(&tv, NULL);
  78
  79     t = (double)tv.tv_sec;
  80     t += (double)tv.tv_usec / 1.0e6;
  81
  82     return t;
  83 }
  84
  85 void add_region(int index, int x, int y, int width, int height)
  86 {
  87     mr[index].enable = 1;
  88     mr[index].x = x;
  89     mr[index].y = y;
  90     mr[index].width = width;
  91     mr[index].height = height;
  92 }
  93
  94 int check_region(int x, int y)
  95 {
  96     register int i;
  97     bool found = false;
  98
  99     for (i = 0; i < 16 && !found; i++) {
 100         if (mr[i].enable && x >= mr[i].x &&
 101             x <= mr[i].x + mr[i].width &&
 102             y >= mr[i].y && y <= mr[i].y + mr[i].height)
 103             found = true;
 104     }
 105     if (!found)
 106         return -1;
 107     return (i - 1);
 108 }
 109
 110 /* handle writing PID file, silently ignore if we can't do it */
 111 void create_pid_file(void)
 112 {
 113     char *home;
 114     char *pid;
 115     FILE *fp;
 116
 117     home = getenv("HOME");
 118     if (home == NULL)
 119         return;
 120
 121     pid = malloc(strlen(home) + 11);
 122     sprintf(pid, "%s/.wmix.pid", home);
 123     fp = fopen(pid, "w");
 124     if (fp) {
 125         fprintf(fp, "%d\n", getpid());
 126         fclose(fp);
 127     }
 128     free(pid);
 129 }