通过udev规则U盘自动挂载

```
# 安装必要的文件系统支持
sudo apt update
sudo apt install -y exfat-fuse exfat-utils ntfs-3g
sudo apt install -y udisks2
```

## 1. `udev`规则文件`/etc/udev/rules.d/99-automount_usb.rules`

`biqu@BTT-CB1:~$ cat /etc/udev/rules.d/99-automount_usb.rules`

```
# 所有品牌U盘通用规则（添加事件）
ACTION=="add", SUBSYSTEM=="block", KERNEL=="sd[a-z][0-9]*", ENV{ID_BUS}=="usb", RUN+="/usr/local/bin/smart_usb_mount.sh"
# 所有品牌U盘通用规则（移除事件）
ACTION=="remove", SUBSYSTEM=="block", KERNEL=="sd[a-z][0-9]*", ENV{ID_BUS}=="usb", RUN+="/usr/local/bin/smart_usb_mount.sh"
```

```
# 添加环境变量传递和权限提升
ACTION=="add", SUBSYSTEM=="block", KERNEL=="sd[a-z][0-9]*", ENV{ID_BUS}=="usb", \
    RUN+="/bin/bash -c 'DEVNAME=%k ACTION=%s /usr/local/bin/smart_usb_mount.sh'"

ACTION=="remove", SUBSYSTEM=="block", KERNEL=="sd[a-z][0-9]*", ENV{ID_BUS}=="usb", \
    RUN+="/bin/bash -c 'DEVNAME=%k ACTION=%s /usr/local/bin/smart_usb_mount.sh'"
```

## U盘自动挂载程序

```bash
biqu@BTT-CB1:~$ cat /usr/local/bin/smart_usb_mount.sh
#!/bin/bash
# /usr/local/bin/smart_usb_mount.sh

# 设置参数（根据实际情况修改）
USER="biqu"  # 替换为你的用户名
TARGET_DIR="/home/$USER/printer_data/gcodes"
STATE_FILE="/tmp/usb_mount_state"
LOG_FILE="/tmp/usb_mount.log"

# 确保日志文件可写
touch "$LOG_FILE"
chmod a+w "$LOG_FILE"

# 日志功能
log() {
    echo "[$(date +'%Y-%m-%d %H:%M:%S')] $1" >> "$LOG_FILE"
}

log "设备事件触发: 动作=$ACTION, 设备=$DEVNAME"

# 获取设备的基础名称（如sdb1）
get_dev_basename() {
    [ -n "$DEVNAME" ] && basename "$DEVNAME"
}

# 清除旧的挂载状态
cleanup_mount() {
    if [ -f "$STATE_FILE" ]; then
        local mounted_dev
        mounted_dev=$(head -n1 "$STATE_FILE" | awk '{print $1}')
        mount_point=$(head -n1 "$STATE_FILE" | awk '{print $2}')
        
        log "清理旧挂载: 设备=$mounted_dev, 挂载点=$mount_point"
        
        # 卸载绑定挂载
        if grep -qs "$TARGET_DIR" /proc/mounts; then
            umount -l "$TARGET_DIR" >> "$LOG_FILE" 2>&1 && log "已卸载绑定挂载"
        fi
        
        # 卸载原始挂载
        if [ -n "$mount_point" ] && grep -qs "$mount_point" /proc/mounts; then
            umount -l "$mount_point" >> "$LOG_FILE" 2>&1 && log "已卸载原始挂载"
            
            # 移除空挂载点
            if [ -d "$mount_point" ]; then
                rmdir "$mount_point" >> "$LOG_FILE" 2>&1 && log "已移除挂载点目录"
            fi
        fi
        
        # 删除状态文件
        rm -f "$STATE_FILE"
    fi
}

# 处理设备添加
handle_add() {
    current_dev=$(get_dev_basename)
    log "检测到新设备: $current_dev"
    
    # 确保设备存在
    if [ ! -b "/dev/$current_dev" ]; then
        log "错误：设备 /dev/$current_dev 不存在！"
        return 1
    fi
    
    # 创建目标目录
    mkdir -p "$TARGET_DIR"
    chown "$USER:$USER" "$TARGET_DIR"
    
    # 清理旧的挂载
    cleanup_mount
    
    # 创建临时挂载点
    MOUNT_POINT=$(mktemp -d /media/usb-XXXXXX)
    chown "$USER:$USER" "$MOUNT_POINT"
    
    # 挂载设备（支持常见文件系统）
    log "挂载设备 /dev/$current_dev 到 $MOUNT_POINT"
    mount -t auto -o nosuid,nodev,uid=$USER,gid=$USER "/dev/$current_dev" "$MOUNT_POINT" >> "$LOG_FILE" 2>&1
    
    if [ $? -ne 0 ]; then
        log "挂载失败！尝试其他文件系统支持..."
        
        # 尝试常见文件系统
        for fs_type in vfat ntfs exfat ext4 ext3 ext2; do
            mount -t $fs_type -o nosuid,nodev,uid=$USER,gid=$USER "/dev/$current_dev" "$MOUNT_POINT" >> "$LOG_FILE" 2>&1
            if [ $? -eq 0 ]; then
                log "成功挂载为 $fs_type 文件系统"
                break
            fi
        done
        
        # 检查是否成功
        grep -qs "$MOUNT_POINT" /proc/mounts
        if [ $? -ne 0 ]; then
            log "所有挂载尝试均失败！"
            rmdir "$MOUNT_POINT"
            return 1
        fi
    fi
    
    # 绑定到目标目录
    log "绑定挂载 $MOUNT_POINT 到 $TARGET_DIR"
    mount --bind "$MOUNT_POINT" "$TARGET_DIR" >> "$LOG_FILE" 2>&1
    chown -R "$USER:$USER" "$TARGET_DIR"
    
    # 保存状态
    echo "$current_dev $MOUNT_POINT" > "$STATE_FILE"
    log "挂载成功！设备内容可在 $TARGET_DIR 访问"
}

# 处理设备移除
handle_remove() {
    current_dev=$(get_dev_basename)
    log "设备移除: $current_dev"
    
    # 检查移除设备是否是当前挂载的设备
    if [ -f "$STATE_FILE" ]; then
        mounted_dev=$(head -n1 "$STATE_FILE" | awk '{print $1}')
        if [ "$mounted_dev" = "$current_dev" ]; then
            log "正在卸载当前使用的设备: $current_dev"
            cleanup_mount
        else
            log "移除的设备 $current_dev 不是当前挂载的设备 (挂载的是 $mounted_dev)"
        fi
    else
        log "无活动挂载状态"
    fi
}

# 主执行逻辑
case "$ACTION" in
    add)
        handle_add
        ;;
    remove)
        handle_remove
        ;;
    *)
        log "未知动作: $ACTION"
        ;;
esac
```

```bash
# 设置权限
sudo chmod +x /usr/local/bin/smart_usb_mount.sh
sudo chown biqu:biqu /usr/local/bin/smart_usb_mount.sh

# 重载 udev 规则
sudo udevadm control --reload-rules
sudo udevadm trigger
或
sudo udevadm control --reload
sudo systemctl restart systemd-udevd

# 测试脚本
# 模拟 U 盘插入
sudo ACTION=add DEVNAME=/dev/sda1 /usr/local/bin/smart_usb_mount.sh
sudo ACTION=remove DEVNAME=/dev/sda1 /usr/local/bin/smart_usb_mount.sh

# 检查挂载结果
ls -la ~/printer_data/gcodes

# 查看详细日志
cat /tmp/usb_mount.log
```

## 3. 查看日志

```bash
tail -f /tmp/usb_mount.log
```

```
# 查看U盘信息
biqu@BTT-CB1:~$ sudo blkid /dev/sda1
/dev/sda1: LABEL="SYSTEM-BOOT" UUID="4422-E958" BLOCK_SIZE="512" TYPE="exfat" PARTUUID="d7068db8-01"

```