Add configurable host directory bind mounts for container entry and command execution.

Signed-off-by: Richard Qin <richard.qin.x@gmail.com>

6 files changed, 120 insertions, 4 deletions

diff --git a/debian-container/README b/debian-container/README
index 15fd95b..b0e11fe 100644
--- a/debian-container/README
+++ b/debian-container/README
@@ -27,11 +27,14 @@ sudo ./debian-container.sh resize test-3 --size 12G
 
 sudo ./debian-container.sh enter test-1
 sudo ./debian-container.sh enter test-1 --network host
+sudo ./debian-container.sh enter test-1 --mount /home/richard/project:/workspace:rw
+sudo ./debian-container.sh enter test-1 --mount /home/richard/data:/data:ro
 
 在容器中执行命令：
 
 sudo ./debian-container.sh exec test-1 -- uname -a
 sudo ./debian-container.sh exec test-1 --network host -- apt-get update
+sudo ./debian-container.sh exec test-1 --mount /home/richard/project:/workspace:rw -- make -C /workspace
 
 列出和查看容器：
 
@@ -74,4 +77,10 @@ DEBIAN_INCLUDE  额外软件包，使用逗号分隔
 DEBIAN_EXCLUDE  要排除的软件包，使用逗号分隔
 DEBIAN_NETWORK  默认网络模式，none 或 host
 
+挂载参数格式：
+
+HOST:CONTAINER[:ro|rw]
+
+目前只支持目录挂载，默认模式为 rw。
+
 脚本实现按职责拆分在 lib/ 目录中，入口脚本只负责加载模块和分发命令。
diff --git a/debian-container/debian-container.sh b/debian-container/debian-container.sh
index 78b0009..d6bfbaf 100755
--- a/debian-container/debian-container.sh
+++ b/debian-container/debian-container.sh
@@ -13,6 +13,7 @@ source "$DC_DIR/lib/common.sh"
 source "$DC_DIR/lib/network.sh"
 source "$DC_DIR/lib/storage.sh"
 source "$DC_DIR/lib/mount.sh"
+source "$DC_DIR/lib/binds.sh"
 source "$DC_DIR/lib/container.sh"
 
 DC_ACTION=${1:-}
@@ -52,7 +53,7 @@ case "$DC_ACTION" in
   init)    dc_init "$@" ;;
   _init)   dc_init_rootfs "$@" ;;
   enter)   dc_enter "$@" ;;
-  _enter)  dc_enter_rootfs ;;
+  _enter)  dc_enter_rootfs "$@" ;;
   exec)    dc_exec "$@" ;;
   _exec)   dc_exec_rootfs "$@" ;;
   resize)  dc_resize "$@" ;;
diff --git a/debian-container/lib/binds.sh b/debian-container/lib/binds.sh
new file mode 100644
index 0000000..7725bd8
--- /dev/null
+++ b/debian-container/lib/binds.sh
@@ -0,0 +1,64 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: GPL-3.0-or-later
+# Copyright (C) 2026 by Richard Qin
+
+DC_BIND_SPECS=()
+DC_BIND_SOURCES=()
+DC_BIND_TARGETS=()
+DC_BIND_MODES=()
+
+dc_bind_add() {
+  local spec=$1
+  local source
+  local target
+  local mode
+  local extra
+
+  IFS=: read -r source target mode extra <<< "$spec"
+  [[ -n "$source" && -n "$target" && -z "$extra" ]] || dc_die "挂载参数格式无效：$spec"
+  [[ "$source" = /* && "$target" = /* ]] || dc_die "挂载源和目标必须使用绝对路径：$spec"
+  [[ "$target" != "/" ]] || dc_die '不能把目录挂载到容器根目录。'
+
+  mode=${mode:-rw}
+  [[ "$mode" == rw || "$mode" == ro ]] || dc_die "挂载模式无效：$mode"
+  source=$(readlink -f -- "$source")
+  [[ -d "$source" ]] || dc_die "挂载源不是目录：$source"
+  target=$(readlink -m -- "$target")
+  [[ "$target" != "/" ]] || dc_die '不能把目录挂载到容器根目录。'
+
+  DC_BIND_SPECS+=("$source:$target:$mode")
+  DC_BIND_SOURCES+=("$source")
+  DC_BIND_TARGETS+=("$target")
+  DC_BIND_MODES+=("$mode")
+}
+
+dc_bind_load_options() {
+  while (($# > 0)); do
+    [[ "$1" == --mount ]] || dc_die '挂载参数格式无效。'
+    (($# >= 2)) || dc_die '--mount 需要一个挂载参数。'
+    dc_bind_add "$2"
+    shift 2
+  done
+}
+
+dc_bind_mount_all() {
+  local index
+  local target
+
+  for index in "${!DC_BIND_SPECS[@]}"; do
+    target="$DC_ROOT${DC_BIND_TARGETS[index]}"
+    mkdir -p "$target"
+    mount --bind "${DC_BIND_SOURCES[index]}" "$target"
+    if [[ "${DC_BIND_MODES[index]}" == ro ]]; then
+      mount -o remount,bind,ro "$target"
+    fi
+  done
+}
+
+dc_bind_cleanup() {
+  local index
+
+  for ((index = ${#DC_BIND_TARGETS[@]} - 1; index >= 0; index--)); do
+    umount "$DC_ROOT${DC_BIND_TARGETS[index]}" 2>/dev/null || true
+  done
+}
diff --git a/debian-container/lib/common.sh b/debian-container/lib/common.sh
index 9fd03b4..4102188 100644
--- a/debian-container/lib/common.sh
+++ b/debian-container/lib/common.sh
@@ -76,6 +76,9 @@ base-create 选项：
 网络选项：
   --network MODE      网络模式：none（默认）或 host
 
+挂载选项：
+  --mount SPEC        目录挂载：HOST:CONTAINER[:ro|rw]
+
 环境变量：
   DEBIAN_INSTANCES  实例目录（默认：当前目录/instances）
   DEBIAN_SIZE       新实例镜像大小（默认：3G）
diff --git a/debian-container/lib/container.sh b/debian-container/lib/container.sh
index eee6d76..5f040e3 100644
--- a/debian-container/lib/container.sh
+++ b/debian-container/lib/container.sh
@@ -181,6 +181,7 @@ dc_base_create() {
 
 dc_enter() {
   local network_mode=$DC_NETWORK_MODE
+  local -a bind_args=()
 
   while (($# > 0)); do
     case "$1" in
@@ -189,6 +190,12 @@ dc_enter() {
         network_mode=$2
         shift 2
         ;;
+      --mount)
+        (($# >= 2)) || dc_die '--mount 需要一个挂载参数。'
+        dc_bind_add "$2"
+        bind_args+=(--mount "${DC_BIND_SPECS[$((${#DC_BIND_SPECS[@]} - 1))]}")
+        shift 2
+        ;;
       --help|-h)
         dc_usage
         return 0
@@ -203,13 +210,15 @@ dc_enter() {
   dc_network_prepare "$network_mode"
 
   unshare --mount --uts --ipc --pid --fork --propagation private \
-    "${DC_NETWORK_UNSHARE_ARGS[@]}" -- bash "$DC_SCRIPT" _enter "$DC_INSTANCE"
+    "${DC_NETWORK_UNSHARE_ARGS[@]}" -- bash "$DC_SCRIPT" _enter "$DC_INSTANCE" "${bind_args[@]}"
 }
 
 dc_enter_rootfs() {
+  dc_bind_load_options "$@"
   dc_mount_root
   trap dc_cleanup_mounts EXIT
   dc_mount_virtual_filesystems
+  dc_bind_mount_all
   hostname debian-container
   echo '已进入独立的 Debian 实验环境；输入 exit 可退出容器。'
 
@@ -220,6 +229,7 @@ dc_enter_rootfs() {
 
 dc_exec() {
   local network_mode=$DC_NETWORK_MODE
+  local -a bind_args=()
 
   while (($# > 0)); do
     case "$1" in
@@ -228,6 +238,12 @@ dc_exec() {
         network_mode=$2
         shift 2
         ;;
+      --mount)
+        (($# >= 2)) || dc_die '--mount 需要一个挂载参数。'
+        dc_bind_add "$2"
+        bind_args+=(--mount "${DC_BIND_SPECS[$((${#DC_BIND_SPECS[@]} - 1))]}")
+        shift 2
+        ;;
       --)
         shift
         break
@@ -248,17 +264,39 @@ dc_exec() {
 
   unshare --mount --uts --ipc --pid --fork --propagation private \
     "${DC_NETWORK_UNSHARE_ARGS[@]}" -- \
-    bash "$DC_SCRIPT" _exec "$DC_INSTANCE" "$@"
+    bash "$DC_SCRIPT" _exec "$DC_INSTANCE" "${bind_args[@]}" -- "$@"
 }
 
 dc_exec_rootfs() {
+  local -a command_args=()
+
+  while (($# > 0)); do
+    case "$1" in
+      --mount)
+        (($# >= 2)) || dc_die '--mount 需要一个挂载参数。'
+        dc_bind_add "$2"
+        shift 2
+        ;;
+      --)
+        shift
+        command_args=("$@")
+        break
+        ;;
+      *)
+        dc_die 'exec 子进程参数格式无效。'
+        ;;
+    esac
+  done
+
+  (($# > 0)) || dc_die 'exec 需要一个命令。'
   dc_mount_root
   trap dc_cleanup_mounts EXIT
   dc_mount_virtual_filesystems
+  dc_bind_mount_all
   hostname debian-container
 
   setpriv --bounding-set=-sys_admin,-net_admin,-net_raw,-sys_module,-sys_boot,-sys_time,-sys_rawio,-sys_ptrace,-syslog -- \
-    chroot "$DC_ROOT" "$@"
+    chroot "$DC_ROOT" "${command_args[@]}"
 }
 
 dc_status() {
diff --git a/debian-container/lib/mount.sh b/debian-container/lib/mount.sh
index 0b623c8..26403c7 100644
--- a/debian-container/lib/mount.sh
+++ b/debian-container/lib/mount.sh
@@ -3,6 +3,7 @@
 # Copyright (C) 2026 by Richard Qin
 
 dc_cleanup_mounts() {
+  dc_bind_cleanup
   umount "$DC_ROOT/dev/pts" 2>/dev/null || true
   umount "$DC_ROOT/dev" 2>/dev/null || true
   umount "$DC_ROOT/proc" 2>/dev/null || true