mount RO

#!/bin/bash

# Function to check if a device is read-only
is_readonly() {
    local device=$1
    if sudo blockdev --getro "$device" | grep -q "1"; then
        return 0
    else
        return 1
    fi
}

# Function to attempt a write and verify read-only status
verify_readonly() {
    local mount_point=$1
    local test_file="$mount_point/.readonly_test"
    
    # Attempt to create a file (should fail if read-only)
    if touch "$test_file" 2>/dev/null; then
        echo "ERROR: Device is not read-only, write operation succeeded!"
        # Cleanup the test file if it was created
        rm -f "$test_file"
        exit 1
    else
        echo "Device is successfully set to read-only, write operation failed as expected."
    fi
}

# Main script
if [ $# -ne 2 ]; then
    echo "Usage: $0 <device> <mount_point>"
    exit 1
fi

DEVICE=$1
MOUNT_POINT=$2

# Remount the filesystem as read-only
echo "Remounting $MOUNT_POINT as read-only..."
if ! sudo mount -o remount,ro "$MOUNT_POINT"; then
    echo "ERROR: Failed to remount $MOUNT_POINT as read-only."
    exit 1
fi

# Set the block device to read-only
echo "Setting $DEVICE to read-only..."
if ! sudo blockdev --setro "$DEVICE"; then
    echo "ERROR: Failed to set $DEVICE to read-only."
    exit 1
fi

# Verify the block device is read-only
if is_readonly "$DEVICE"; then
    echo "$DEVICE is set to read-only."
else
    echo "ERROR: $DEVICE is not set to read-only."
    exit 1
fi

# Verify the filesystem is read-only
verify_readonly "$MOUNT_POINT"

echo "All checks passed. $DEVICE is now read-only."
exit 0