Add usage/help message and CLI argument parsing

Added comprehensive command-line interface with:
- -h, --help: Show usage information
- -v, --version: Show version
- -d, --debug: Enable debug output
- -s, --skip-smart: Skip SMART data collection (faster)
- --no-ceph: Skip Ceph OSD information
- --show-pci: Display PCI paths for debugging

The script now properly respects these flags throughout execution.

Fixes: #10

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

driveAtlas.sh

@@ -5,6 +5,84 @@
 # Maps physical drive bays to logical device names using PCI paths
 #==============================================================================
 
+VERSION="1.1.0"
+
+#------------------------------------------------------------------------------
+# show_usage
+#
+# Displays help message with usage information and available options.
+#------------------------------------------------------------------------------
+show_usage() {
+    cat << EOF
+Drive Atlas v${VERSION} - Server Drive Mapping Tool
+
+Maps physical drive bays to logical device names using PCI paths.
+Displays visual chassis layouts and comprehensive drive information.
+
+USAGE:
+    $(basename "$0") [OPTIONS]
+
+OPTIONS:
+    -h, --help          Show this help message and exit
+    -v, --version       Show version information
+    -d, --debug         Enable debug output (show drive mappings)
+    -s, --skip-smart    Skip SMART data collection (faster)
+    --no-ceph           Skip Ceph OSD information
+    --show-pci          Show PCI paths in output
+
+EXAMPLES:
+    $(basename "$0")                  # Normal run with all features
+    $(basename "$0") --skip-smart     # Fast run without SMART data
+    $(basename "$0") --debug          # Show mapping debug info
+
+ENVIRONMENT VARIABLES:
+    DEBUG=1             Same as --debug flag
+
+For more information, see: https://code.lotusguild.org/LotusGuild/driveAtlas
+EOF
+}
+
+#------------------------------------------------------------------------------
+# Command Line Argument Parsing
+#------------------------------------------------------------------------------
+SKIP_SMART=false
+SKIP_CEPH=false
+SHOW_PCI=false
+
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        -h|--help)
+            show_usage
+            exit 0
+            ;;
+        -v|--version)
+            echo "Drive Atlas v${VERSION}"
+            exit 0
+            ;;
+        -d|--debug)
+            DEBUG=1
+            shift
+            ;;
+        -s|--skip-smart)
+            SKIP_SMART=true
+            shift
+            ;;
+        --no-ceph)
+            SKIP_CEPH=true
+            shift
+            ;;
+        --show-pci)
+            SHOW_PCI=true
+            shift
+            ;;
+        *)
+            echo "Unknown option: $1" >&2
+            echo "Use --help for usage information." >&2
+            exit 1
+            ;;
+    esac
+done
+
 #------------------------------------------------------------------------------
 # Dependency Checks
 # Verifies required commands are available before running
@@ -313,21 +391,27 @@ get_storage_controllers() {
 # Builds a global associative array mapping physical bay numbers to device names.
 # Uses PCI paths from SERVER_MAPPINGS to resolve current device assignments.
 #
-# Sets: DRIVE_MAP (global associative array)
+# Sets:
-#   Keys: Bay identifiers (1, 2, ..., m2-1, m2-2, etc.)
+#   DRIVE_MAP (global associative array)
-#   Values: Device names (sda, nvme0n1, etc.)
+#     Keys: Bay identifiers (1, 2, ..., m2-1, m2-2, etc.)
+#     Values: Device names (sda, nvme0n1, etc.)
+#   BAY_TO_PCI_PATH (global associative array)
+#     Keys: Bay identifiers
+#     Values: PCI path strings (for --show-pci option)
 #------------------------------------------------------------------------------
 build_drive_map() {
     local host="$(hostname)"
     local mapping="${SERVER_MAPPINGS[$host]}"
 
-    # Declare global array directly instead of copying from local
+    # Declare global arrays directly
     declare -g -A DRIVE_MAP=()
+    declare -g -A BAY_TO_PCI_PATH=()
 
     if [[ -n "$mapping" ]]; then
         while read -r path slot; do
             [[ -z "$path" || -z "$slot" ]] && continue
 
+            BAY_TO_PCI_PATH[$slot]="$path"
             if [[ -L "/dev/disk/by-path/$path" ]]; then
                 local drive="$(readlink -f "/dev/disk/by-path/$path" | sed 's/.*\///')"
                 DRIVE_MAP[$slot]="$drive"
@@ -509,11 +593,18 @@ esac
 #------------------------------------------------------------------------------
 
 # Build Ceph OSD cache (single query instead of per-device)
-build_ceph_cache
+if [[ "$SKIP_CEPH" != true ]]; then
+    build_ceph_cache
+fi
 
 printf "\n=== Drive Details with SMART Status (by Bay Position) ===\n"
-printf "%-5s %-15s %-10s %-8s %-8s %-8s %-30s %-20s %-12s %-10s %-10s\n" "BAY" "DEVICE" "SIZE" "TYPE" "TEMP" "HEALTH" "MODEL" "SERIAL" "CEPH OSD" "STATUS" "USAGE"
+if [[ "$SHOW_PCI" == true ]]; then
-echo "----------------------------------------------------------------------------------------------------------------------------------------------------"
+    printf "%-5s %-15s %-10s %-8s %-8s %-8s %-30s %-20s %-12s %-10s %-10s %-40s\n" "BAY" "DEVICE" "SIZE" "TYPE" "TEMP" "HEALTH" "MODEL" "SERIAL" "CEPH OSD" "STATUS" "USAGE" "PCI PATH"
+    echo "------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------"
+else
+    printf "%-5s %-15s %-10s %-8s %-8s %-8s %-30s %-20s %-12s %-10s %-10s\n" "BAY" "DEVICE" "SIZE" "TYPE" "TEMP" "HEALTH" "MODEL" "SERIAL" "CEPH OSD" "STATUS" "USAGE"
+    echo "----------------------------------------------------------------------------------------------------------------------------------------------------"
+fi
 
 # Build reverse map: device -> bay
 declare -A DEVICE_TO_BAY
@@ -530,22 +621,34 @@ all_bays=$(printf '%s\n' "${!DRIVE_MAP[@]}" | grep -E '^[0-9]+$' | sort -n; prin
 for bay in $all_bays; do
     device="${DRIVE_MAP[$bay]}"
     if [[ -n "$device" && "$device" != "EMPTY" && -b "/dev/$device" ]]; then
-        size=$(lsblk -d -n -o SIZE "/dev/$device" 2>/dev/null)
+        size="$(lsblk -d -n -o SIZE "/dev/$device" 2>/dev/null)"
-        smart_info=$(get_drive_smart_info "$device")
+
-        IFS='|' read -r type temp health model serial <<< "$smart_info"
+        # Get SMART info (or defaults if skipped)
+        if [[ "$SKIP_SMART" == true ]]; then
+            type="-"
+            temp="-"
+            health="-"
+            model="-"
+            serial="-"
+        else
+            smart_info="$(get_drive_smart_info "$device")"
+            IFS='|' read -r type temp health model serial <<< "$smart_info"
+        fi
 
         # Check for Ceph OSD using cached data
-        osd_id="${CEPH_DEVICE_TO_OSD[$device]:-}"
+        osd_id="-"
         ceph_status="-"
-
+        if [[ "$SKIP_CEPH" != true ]]; then
-        if [[ -n "$osd_id" ]]; then
+            osd_id="${CEPH_DEVICE_TO_OSD[$device]:-}"
-            # Get status from cached OSD tree data
+            if [[ -n "$osd_id" ]]; then
-            osd_num="${osd_id#osd.}"
+                # Get status from cached OSD tree data
-            up_status="${CEPH_OSD_STATUS[$osd_num]:-unknown}"
+                osd_num="${osd_id#osd.}"
-            in_status="${CEPH_OSD_IN[$osd_num]:-out}"
+                up_status="${CEPH_OSD_STATUS[$osd_num]:-unknown}"
-            ceph_status="${up_status}/${in_status}"
+                in_status="${CEPH_OSD_IN[$osd_num]:-out}"
-        else
+                ceph_status="${up_status}/${in_status}"
-            osd_id="-"
+            else
+                osd_id="-"
+            fi
         fi
 
         # Check mount points using lsblk (includes partitions)
@@ -566,7 +669,12 @@ for bay in $all_bays; do
             fi
         fi
 
-        printf "%-5s %-15s %-10s %-8s %-8s %-8s %-30s %-20s %-12s %-10s %-10s\n" "$bay" "/dev/$device" "$size" "$type" "$temp" "$health" "$model" "$serial" "$osd_id" "$ceph_status" "$usage"
+        if [[ "$SHOW_PCI" == true ]]; then
+            pci_path="${BAY_TO_PCI_PATH[$bay]:-}"
+            printf "%-5s %-15s %-10s %-8s %-8s %-8s %-30s %-20s %-12s %-10s %-10s %-40s\n" "$bay" "/dev/$device" "$size" "$type" "$temp" "$health" "$model" "$serial" "$osd_id" "$ceph_status" "$usage" "$pci_path"
+        else
+            printf "%-5s %-15s %-10s %-8s %-8s %-8s %-30s %-20s %-12s %-10s %-10s\n" "$bay" "/dev/$device" "$size" "$type" "$temp" "$health" "$model" "$serial" "$osd_id" "$ceph_status" "$usage"
+        fi
     fi
 done