1 files changed, 85 insertions, 0 deletions

diff --git a/scripts/mkdisk.sh b/scripts/mkdisk.sh
new file mode 100755
index 0000000..f9a8c09
--- /dev/null
+++ b/scripts/mkdisk.sh
@@ -0,0 +1,85 @@
+#!/usr/bin/env bash
+#
+# scripts/mkdisk.sh — create (or re-create) the FAT32 data disk that the
+# kernel mounts at /disk.
+#
+# Usage:
+#   ./scripts/mkdisk.sh                 # create /tmp/disk.img (64M) if missing
+#   ./scripts/mkdisk.sh --fresh         # re-format (wipes the image!)
+#   ./scripts/mkdisk.sh --size 128M     # different size (default 64M)
+#   ./scripts/mkdisk.sh /path/img       # custom image path
+#   ./scripts/mkdisk.sh --no-seed       # skip the seed/ directory
+#
+# The image is created with `mkfs.fat -C`, which is the option that
+# actually creates the file — plain `mkfs.fat` only writes into an
+# existing one.  Files from seed/ (if present) are copied in with mtools.
+#
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+PROJECT_DIR="$(dirname "$SCRIPT_DIR")"
+
+IMG="/tmp/disk.img"
+SIZE="64M"
+FRESH=0
+SEED_DIR="$PROJECT_DIR/seed"
+
+while [ $# -gt 0 ]; do
+        case "$1" in
+        --fresh) FRESH=1 ;;
+        --size)
+                shift
+                SIZE="$1"
+                ;;
+        --no-seed) SEED_DIR="" ;;
+        --help | -h)
+                head -20 "$0" | grep "^#" | sed 's/^# \?//'
+                exit 0
+                ;;
+        *)
+                IMG="$1"
+                ;;
+        esac
+        shift
+done
+
+if [ -f "$IMG" ] && [ "$FRESH" -eq 0 ]; then
+        echo "mkdisk: $IMG already exists (use --fresh to re-format)"
+        exit 0
+fi
+
+if ! command -v mkfs.fat >/dev/null 2>&1; then
+        echo "mkdisk: mkfs.fat not found — install dosfstools (sudo apt install dosfstools)" >&2
+        exit 1
+fi
+
+# mkfs.fat sizes are 1024-byte blocks; accept M/G/K suffixes too.
+case "$SIZE" in
+*G) SIZE_BLOCKS=$(( ${SIZE%G} * 1024 * 1024 )) ;;
+*M) SIZE_BLOCKS=$(( ${SIZE%M} * 1024 )) ;;
+*K) SIZE_BLOCKS=$(( ${SIZE%K} )) ;;
+*)      SIZE_BLOCKS="$SIZE" ;;
+esac
+if [ -z "$SIZE_BLOCKS" ] || [ "$SIZE_BLOCKS" -le 0 ] 2>/dev/null; then
+        echo "mkdisk: bad size '$SIZE' (use e.g. 64M or 65536)" >&2
+        exit 1
+fi
+
+echo "mkdisk: creating $IMG ($SIZE FAT32, label RSDOS)"
+rm -f "$IMG"
+mkfs.fat -C -F 32 -n RSDOS "$IMG" "$SIZE_BLOCKS"
+
+if [ -n "$SEED_DIR" ] && [ -d "$SEED_DIR" ]; then
+        if ! command -v mcopy >/dev/null 2>&1; then
+                echo "mkdisk: warning: mcopy not found — skipping seed files (install mtools)" >&2
+        else
+                echo "mkdisk: seeding from $SEED_DIR/"
+                for f in "$SEED_DIR"/*; do
+                        [ -f "$f" ] || continue
+                        mcopy -i "$IMG" "$f" "::/$(basename "$f")"
+                        echo "  -> $(basename "$f")"
+                done
+        fi
+fi
+
+echo "mkdisk: done — boot with: make run   (or: ./scripts/boot.sh)"