From c1e840fa9f7053fc52285878148e48ee3b5418f7 Mon Sep 17 00:00:00 2001
From: cimryan <cimryan@hotmail.com>
Date: Sun, 14 Oct 2018 20:39:12 -0700
Subject: [PATCH] Make calculations of backng file size in terms of free 1k
 blocks

---
 windows_archive/create-backingfiles.sh | 14 +++++++-------
 windows_archive/setup-teslausb         |  9 +++++----
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/windows_archive/create-backingfiles.sh b/windows_archive/create-backingfiles.sh
index 7c29783..df6cbd2 100644
--- a/windows_archive/create-backingfiles.sh
+++ b/windows_archive/create-backingfiles.sh
@@ -1,8 +1,7 @@
 #!/bin/bash -eu
 
-SPACE_TO_USE="$1"
-CAM_PERCENT="$2"
-BACKINGFILES_MOUNTPOINT="$3"
+CAM_PERCENT="$1"
+BACKINGFILES_MOUNTPOINT="$2"
 
 G_MASS_STORAGE_CONF_FILE_NAME=/etc/modprobe.d/g_mass_storage.conf
 
@@ -12,7 +11,7 @@ function add_drive () {
   local size="$3"
 
   local filename="$4"
-  fallocate -l "$size" "$filename"
+  fallocate -l "$size"K "$filename"
   mkfs.vfat "$filename" -F 32 -n "$label"
 
   local mountpoint=/mnt/"$name"
@@ -21,14 +20,15 @@ function add_drive () {
   echo "$filename $mountpoint vfat noauto,users,umask=000 0 0" >> /etc/fstab
 }
 
-CAM_DISK_SIZE="$(( $SPACE_TO_USE * $CAM_PERCENT / 100 ))"
+FREE_1K_BLOCKS="$(df --output=avail --block-size=1K /backingfiles/ | tail -n 1)"
+
+CAM_DISK_SIZE="$(( $FREE_1K_BLOCKS * $CAM_PERCENT / 100 ))"
 CAM_DISK_FILE_NAME="$BACKINGFILES_MOUNTPOINT/cam_disk.bin"
 add_drive "cam" "CAM" "$CAM_DISK_SIZE" "$CAM_DISK_FILE_NAME"
 
 if [ "$CAM_PERCENT" -lt 100 ]
 then
-  MUSIC_PERCENT="$(( 100 - $CAM_PERCENT ))"
-  MUSIC_DISK_SIZE="$(( $SPACE_TO_USE * $MUSIC_PERCENT / 100 ))"
+  MUSIC_DISK_SIZE="$(df --output=avail --block-size=1K /backingfiles/ | tail -n 1)"
   MUSIC_DISK_FILE_NAME="$BACKINGFILES_MOUNTPOINT/music_disk.bin"
   add_drive "music" "MUSIC" "$MUSIC_DISK_SIZE" "$MUSIC_DISK_FILE_NAME"
   echo "options g_mass_storage file=$CAM_DISK_FILE_NAME,$MUSIC_DISK_FILE_NAME removable=1,1 ro=0,0 stall=0 iSerialNumber=123456" > G_MASS_STORAGE_CONF_FILE_NAME
diff --git a/windows_archive/setup-teslausb b/windows_archive/setup-teslausb
index a083c2e..8f6bc0f 100644
--- a/windows_archive/setup-teslausb
+++ b/windows_archive/setup-teslausb
@@ -33,7 +33,9 @@ function check_archive_server_reachable () {
 
 function check_available_space () {
   echo "Verifying that there is sufficient space available on the MicroSD card..."
-  local available_space="$1"
+  
+  local available_space="$( parted -m /dev/mmcblk0 u b print free | tail -1 | cut -d ":" -f 4 | sed 's/B//g' )"
+
   if [ "$available_space" -lt  4294967296 ]
   then
     echo "STOP: The MicroSD card is too small."
@@ -66,7 +68,7 @@ function create_usb_drive_backing_files () {
   
   wget https://raw.githubusercontent.com/cimryan/teslausb/"$BRANCH"/windows_archive/create-backingfiles.sh
   chmod +x ./create-backingfiles.sh
-  ./create-backingfiles.sh "$AVAILABLE_SPACE" "$campercent" "$BACKINGFILES_MOUNTPOINT" 
+  ./create-backingfiles.sh "$campercent" "$BACKINGFILES_MOUNTPOINT" 
 }
 
 function configure_archive () {
@@ -141,8 +143,7 @@ check_variable "campercent"
 
 check_archive_server_reachable
 
-AVAILABLE_SPACE="$( parted -m /dev/mmcblk0 u b print free | tail -1 | cut -d ":" -f 4 | sed 's/B//g' )"
-check_available_space "$AVAILABLE_SPACE"
+check_available_space
 
 
 pushd ~