Make backup / restore use POSIX shell for portability.

[qbit]

Signed-off-by: Aaron Bieber aaron@bolddaemon.com

Compatibility / Usability fixes for backup / restore scripts.

Description

This removes the hard dependency on bash and adds getopts flags to the backup / restore scripts.

Removal of bash because there are simple scripts (no need for bash specific features), and not all systems ship with bash by default.

Motivation and Context

Personally I can't remember the order of things like $1, $2, so every time I backup I have to view the scripts.

How Has This Been Tested?

Backups and restores have been done.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have signed-off my commits with git commit -s

[kdomanski]

The ${FILES_TO_BACKUP[@]} array expansion is not POSIX-compliant and on my linux /bin/sh it causes:

./scripts/backup.sh: 57: Bad substitution

Are you on macOS by any chance? Does it work there?

[qbit]

Ah crap. Looks like it's broken on macos for different reasons (ping has no -w).

I am on OpenBSD which expands as expected (as does macos once you get pas the -w issue)

Do you know what shell /bin/sh is on your flavor of linux?

*"expands as expected" - maybe "expands as unexpected" is better here :P

[evilsocket]

please @qbit send a fix

[qbit]

@kdomanski can you confirm that this diff works for you?

diff --git a/scripts/backup.sh b/scripts/backup.sh
index 3ba9fd8..9c58dbd 100755
--- a/scripts/backup.sh
+++ b/scripts/backup.sh
@@ -48,10 +48,10 @@ FILES_TO_BACKUP="/root/brain.nn \
   /home/pi/.bashrc \
   /home/pi/.profile"
 
-ping -w 3 -c 1 "${UNIT_HOSTNAME}" > /dev/null 2>&1 || {
+ping -c 1 "${UNIT_HOSTNAME}" > /dev/null 2>&1 || {
   echo "@ unit ${UNIT_HOSTNAME} can't be reached, make sure it's connected and a static IP assigned to the USB interface."
   exit 1
 }
 
 echo "@ backing up $UNIT_HOSTNAME to $OUTPUT ..."
-ssh "${USERNAME}@${UNIT_HOSTNAME}" "sudo find ${FILES_TO_BACKUP[@]} -print0 | xargs -0 sudo tar cv" | gzip -9 > "$OUTPUT"
+ssh "${USERNAME}@${UNIT_HOSTNAME}" "sudo find ${FILES_TO_BACKUP} -print0 | xargs -0 sudo tar cv" | gzip -9 > "$OUTPUT"
diff --git a/scripts/restore.sh b/scripts/restore.sh
index 6303f88..551094e 100755
--- a/scripts/restore.sh
+++ b/scripts/restore.sh
@@ -44,7 +44,7 @@ fi
 # username to use for ssh
 USERNAME=${USERNAME:-pi}
 
-ping -w 3 -c 1 "${UNIT_HOSTNAME}" > /dev/null 2>&1 || {
+ping -c 1 "${UNIT_HOSTNAME}" > /dev/null 2>&1 || {
   echo "@ unit ${UNIT_HOSTNAME} can't be reached, make sure it's connected and a static IP assigned to the USB interface."
   exit 1
 }

[kdomanski]

I'm on Ubuntu, my sh implementation appears to be dash. The patch above fixes it for me.