Fix multi-line init commands being split on embedded newlines

[Copilot]

Fix multi-line init commands being split by startup script

Problem

The startup script at /ssh/rootfs/etc/s6-overlay/s6-rc.d/init-user/run was using while read -r cmd to process init_commands, which splits on newlines. This caused multi-line commands (like heredocs) to be incorrectly split into multiple separate commands, resulting in syntax errors.

Solution Implemented

• Analyze the issue and understand the root cause
• Fix the init_commands processing to handle multi-line commands properly using array index iteration
• Test the fix manually with multi-line heredoc commands
• Add error handling for array operations
• Use bashio::config abstraction instead of direct file access
• Run shellcheck linter
• Address code review feedback

Changes Made

Modified /ssh/rootfs/etc/s6-overlay/s6-rc.d/init-user/run (lines 109-122):

Before:

if bashio::config.has_value 'init_commands'; then
    while read -r cmd; do
        eval "${cmd}" \
            || bashio::exit.nok "Failed executing init command: ${cmd}"
    done <<< "$(bashio::config 'init_commands')"
fi

After:

if bashio::config.has_value 'init_commands'; then
    # Use bashio::config to properly iterate over the array, preserving multi-line commands
    length=$(bashio::config 'init_commands | length') \
        || bashio::exit.nok 'Failed to get init_commands array length'
    
    for (( i=0; i<length; i++ )); do
        cmd=$(bashio::config "init_commands[${i}]") \
            || bashio::exit.nok "Failed to get init command at index ${i}"
        
        eval "${cmd}" \
            || bashio::exit.nok "Failed executing init command: ${cmd}"
    done
fi

Key Improvements

1. Preserves multi-line strings: Using array index iteration ensures each command is extracted as a complete string, including embedded newlines
2. Uses bashio abstraction: Now uses bashio::config with jq-style queries instead of directly accessing /data/options.json
3. Proper error handling: Added error checking for array operations
4. Maintains compatibility: Single-line commands continue to work exactly as before

Testing Completed

✅ Simple single-line commands
✅ Multi-line heredoc commands
✅ Complex commands with special characters
✅ bashio::config abstraction layer
✅ Shellcheck linter passed

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Multi-line init commands are implicitly split by startup script</issue_title>
<issue_description>I have this in my configuration.yaml for this great add-on:

init_commands:
  - cp -ar /data/system/* /
  - pip install --break-system-packages mpremote
  - |
    cat >> ~/.zshrc <<'EOF'
    # Use GNU nano as default editor in shell
    export EDITOR=nano

    # Enable command-not-found integration
    command_not_found_handler() {
        /usr/libexec/command-not-found "$@";
    }
    EOF

As you can see it attempts to append several configuration lines to the Zshell configuration file on addon startup.

The newlines are correctly stored in the addon options (/mnt/data/supervisor/addons/data/a0d7b954_ssh/options.json):

{
  …
  "init_commands": [
    "cp -ar /data/system/* /",
    "pip install --break-system-packages mpremote",
    "cat >> ~/.zshrc <<'EOF'\n# Use GNU nano as default editor in shell\nexport EDITOR=nano\n\n# Enable command-not-found integration\ncommand_not_found_handler() {\n    /usr/libexec/command-not-found \"$@\";\n}\nEOF\n"
  ]
}

However the add-on’s startup script breaks them into multiple lines:
https://github.com/hassio-addons/addon-ssh/blob/50c387cb56f30ea3acfd401a7978136ea392cc5a/ssh/rootfs/etc/s6-overlay/s6-rc.d/init-user/run#L110-L115

Causing errors when executing this code:

/etc/s6-overlay/s6-rc.d/init-user/run: line 112: warning: here-document at line 112 delimited by end-of-file (wanted `EOF')
/etc/s6-overlay/s6-rc.d/init-user/run: eval: line 113: syntax error: unexpected end of file
[21:04:49] FATAL: Failed executing init command: command_not_found_handler() {
s6-rc: warning: unable to start service init-user: command exited 1
/run/s6/basedir/scripts/rc.init: warning: s6-rc failed to properly bring all the services up! Check your logs (in /run/uncaught-logs/current if you have in-container logging) for more information.
/run/s6/basedir/scripts/rc.init: fatal: stopping the container.
```</issue_description>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>

• Fixes Multi-line init commands are implicitly split by startup script #976

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