sonic-buildimage/functions.sh
2016-08-04 10:39:33 -07:00

52 lines
1.8 KiB
Bash

#!/bin/bash
## Function Definitions
## Function: trap_push 'COMMAND_STRING'
## Appends a command to a trap, which is needed because default trap behavior is to replace
## previous trap for the same signal
## - 1st arg: code to add
## - ref: http://stackoverflow.com/questions/3338030/multiple-bash-traps-for-the-same-signal
_trap_push() {
local next="$1"
eval "trap_push() {
local oldcmd='$(echo "$next" | sed -e s/\'/\'\\\\\'\'/g)'
local newcmd=\"\$1; \$oldcmd\"
trap -- \"\$newcmd\" EXIT INT TERM HUP
_trap_push \"\$newcmd\"
}"
}
_trap_push true
## Function: warn MESSAGE
## Print message to stderr
warn() {
local message="$1"
echo "$message" >&2
}
## Function: die MESSAGE
## Print message to stderr and exit the whole process
## Note:
## Using () makes the command inside them run in a sub-shell and calling a exit from there
## causes you to exit the sub-shell and not your original shell, hence execution continues in
## your original shell. To overcome this use { }
## ref: http://stackoverflow.com/questions/3822621/how-to-exit-if-a-command-failed
die() {
local message="$1"
warn "$message"
exit 1
}
docker_try_rmi() {
local image_name="$1"
## Note: inspect output has quotation characters, so sed to remove it as an argument
local image_id=$(docker inspect --format="{{json .Id}}" $image_name | sed -e 's/^"//' -e 's/"$//')
[ -z "$image_id" ] || {
## Remove all the exited containers from this image
docker ps -a -q -f "status=exited" -f "ancestor=$1" | xargs --no-run-if-empty docker rm
## Note: If there are running containers from this image, the build system is in an
## unexpected state. The 'rmi' will fail and we need investigate the build environment.
docker rmi $image_name
}
}