Simple script to mount .img files in linux so that you can access the contents, copy files, etc.

mount-image.sh

#!/bin/bash

# Script Title: Loopback Image Mounter
# Description: This script facilitates the mounting of disk image files to a specified loopback device and directory. 
#              It supports multiple functionalities including listing partitions in the image file, unmounting, 
#              and flexible mounting options. It is beneficial for users working with disk images, aiding in 
#              efficiently managing and accessing the contents of these files.
# Collaboration: This script was developed in collaboration between a human and OpenAI's ChatGPT, leveraging 
#                the AI's coding expertise to implement the specified functionalities and maintain a user-friendly 
#                interface.

# Default values
PART=p2
MNTDIR=/mnt/loopimage
READONLY=true

# Function to display help information
display_help() {
    echo "Usage: $0 [options...]"
    echo
    echo "Options:"
    echo " -i, --img <path>         Specify the path to the image file or directory (required)"
    echo " -p, --part <partition>   Specify the partition (default: p2)"
    echo " -m, --mnt <directory>    Specify the mount directory (default: /mnt/loopimage)"
    echo " -w, --writemode          Mount the image in write mode (default: read-only)"
    echo " -u, --unmount            Unmount the loopback device"
    echo " --list                   List the partitions in the image file"
    echo " -?, --help               Display this help message"
    echo
}

# Process command line options
while getopts "i:p:m:w?u-:" opt; do
    case "${opt}" in
        i)  IMG="${OPTARG}" ;;
        p)  PART="${OPTARG}" ;;
        m)  MNTDIR="${OPTARG}" ;;
        w)  READONLY=false ;;
        u)  UNMOUNT=true ;;
        -)  
            case "${OPTARG}" in
                img)       IMG="${!OPTIND}"; OPTIND=$((OPTIND + 1)) ;;
                part)      PART="${!OPTIND}"; OPTIND=$((OPTIND + 1)) ;;
                mnt)       MNTDIR="${!OPTIND}"; OPTIND=$((OPTIND + 1)) ;;
                writemode) READONLY=false ;;
                unmount)   UNMOUNT=true ;;
                list)      LIST_PARTITIONS=true ;;
                help)      display_help; exit 0 ;;
                *)         echo "Unknown option --${OPTARG}"; display_help; exit 1 ;;
            esac
            ;;
        ?)  display_help; exit 0 ;;
        *)  echo "Unknown option -${OPTARG}"; display_help; exit 1 ;;
    esac
done

# Verify that the image path has been provided
if [ -z "$IMG" ]; then
    echo
    echo "Error: You must specify an image path using the -i or --img option."
    echo
    display_help
    exit 1
fi

# Check if the specified image file or directory exists
if [ ! -e "$IMG" ]; then
    echo
    echo "Error: The specified image path does not exist."
    echo
    exit 1
fi

# If IMG is a directory, find all .img files in it
if [ -d "$IMG" ]; then
    mapfile -t IMG_FILES < <(find "$IMG" -type f -name "*.img")
    IMG_COUNT=${#IMG_FILES[@]}
    
    if (( IMG_COUNT == 0 )); then
        echo
        echo "Error: No .img files found in the specified directory."
        echo
        exit 1
    elif (( IMG_COUNT == 1 )); then
        IMG="${IMG_FILES[0]}"
    else
        echo "Multiple .img files found. Please select one:"
        select IMG in "${IMG_FILES[@]}"; do
            if [[ -n "$IMG" ]]; then
                break
            else
                echo "Invalid selection. Please try again."
            fi
        done
    fi
fi

# Check if unmount flag is set; if so, unmount and exit
if [ "$UNMOUNT" == "true" ]; then
    echo
    echo "Unmounting..."
    umount "${MNTDIR}"
    losetup -d "$(losetup -j "${IMG}" | cut -d ':' -f1)"
    exit 0
fi

# If the list partitions flag is set, list the partitions and exit
if [ "$LIST_PARTITIONS" == "true" ]; then
    LOOP=$(losetup --show -f -P -L "${IMG}")
    echo
    echo "Listing partitions for $IMG:"
    fdisk -l "${LOOP}"
    losetup -d "${LOOP}"
    exit 0
fi

# Prepare the mount directory
mkdir -p "$MNTDIR"

# Set up the loop device with the image file
LOOP=$(losetup --show -f -P -L "${IMG}")

# Determine the mount options based on whether read-only or write mode is requested
MNT_OPTIONS="ro"
if [ "$READONLY" == "false" ]; then
    MNT_OPTIONS="rw"
fi

# Mount the specified partition of the image file
if ! mount -o ${MNT_OPTIONS} "${LOOP}${PART}" "${MNTDIR}"; then
    echo
    echo "Error: Failed to mount the image. Check the partition and mount point."
    echo
    exit 1
fi

echo
echo -e "Listing files for \033[1;32m${IMG}\033[0m:"
ls "${MNTDIR}"

echo
echo -e "Mounted: \033[1;32m${IMG}\033[0m on \033[1;32m${MNTDIR}\033[0m"
echo