[fix][dfs] 修复ramfs与tmpfs对文件名超长的处理逻辑

[Unbear-Hz]

拉取/合并请求描述：(PR description)

[

为什么提交这份PR (why to submit this PR)

tmpfs对超长文件名无保护，会导致溢出，且被截断
ramfs对超长文件名有保护，但会被截断

你的解决方案是什么 (what is your solution)

参考V1版本的实现，修复V2版本ramfs与tmpfs对文件名超长的处理逻辑

请提供验证的bsp和config (provide the config and bsp)

• BSP:

• .config:

• action:

]

当前拉取/合并请求的状态 Intent for your PR

必须选择一项 Choose one (Mandatory):

• 本拉取/合并请求是一个草稿版本 This PR is for a code-review and is intended to get feedback
• 本拉取/合并请求是一个成熟版本 This PR is mature, and ready to be integrated into the repo

代码质量 Code Quality：

我在这个拉取/合并请求中已经考虑了 As part of this pull request, I've considered the following:

• 已经仔细查看过代码改动的对比 Already check the difference between PR and old code
• 代码风格正确，包括缩进空格，命名及其他风格 Style guide is adhered to, including spacing, naming and other styles
• 没有垃圾代码，代码尽量精简，不包含#if 0代码，不包含已经被注释了的代码 All redundant code is removed and cleaned up
• 所有变更均有原因及合理的，并且不会影响到其他软件组件代码或BSP All modifications are justified and not affect other components or BSP
• 对难懂代码均提供对应的注释 I've commented appropriately where code is tricky
• 代码是高质量的 Code in this PR is of high quality
• 已经使用clang-format 源码格式化工具确保格式符合RT-Thread代码规范 This PR has been formatted with clang-format and complies with RT-Thread code specification
• 如果是新增bsp, 已经添加ci检查到.github/ALL_BSP_COMPILE.json 详细请参考链接BSP自查

[github-actions]

👋 感谢您对 RT-Thread 的贡献！Thank you for your contribution to RT-Thread!

为确保代码符合 RT-Thread 的编码规范，请在你的仓库中执行以下步骤运行代码格式化工作流（如果格式化CI运行失败）。
To ensure your code complies with RT-Thread's coding style, please run the code formatting workflow by following the steps below (If the formatting of CI fails to run).

---

🛠 操作步骤 | Steps

1. 前往 Actions 页面 | Go to the Actions page
   点击进入工作流 → | Click to open workflow →

2. 点击 Run workflow | Click Run workflow

• 设置需排除的文件/目录（目录请以"/"结尾）
  Set files/directories to exclude (directories should end with "/")
• 将目标分支设置为 \ Set the target branch to：tmp_debugv1
• 设置PR number为 \ Set the PR number to：11624

3. 等待工作流完成 | Wait for the workflow to complete
   格式化后的代码将自动推送至你的分支。
   The formatted code will be automatically pushed to your branch.

完成后，提交将自动更新至 tmp_debugv1 分支，关联的 Pull Request 也会同步更新。
Once completed, commits will be pushed to the tmp_debugv1 branch automatically, and the related Pull Request will be updated.

如有问题欢迎联系我们，再次感谢您的贡献！💐
If you have any questions, feel free to reach out. Thanks again for your contribution!

[github-actions]

📌 Code Review Assignment

🏷️ Tag: components

Reviewers: @Maihuanyi

Changed Files (Click to expand)

• components/dfs/dfs_v2/filesystems/ramfs/dfs_ramfs.c
• components/dfs/dfs_v2/filesystems/tmpfs/dfs_tmpfs.c

---

📊 Current Review Status (Last Updated: 2026-07-16 23:27 CST)

• ⌛ @Maihuanyi Pending Review

---

📝 Review Instructions

1. 维护者可以通过单击此处来刷新审查状态: 🔄 刷新状态
   Maintainers can refresh the review status by clicking here: 🔄 Refresh Status

2. 确认审核通过后评论 LGTM/lgtm
   Comment LGTM/lgtm after confirming approval

3. PR合并前需至少一位维护者确认
   PR must be confirmed by at least one maintainer before merging

ℹ️ 刷新CI状态操作需要具备仓库写入权限。
ℹ️ Refresh CI status operation requires repository Write permission.

[github-actions]

MemBrowse Memory Report

gd32105r-start

• CODE: .data +4 B, .text +16,644 B (+31.6%, 69,296 B / 262,144 B, total: 26% used)
• DATA: .bss +416 B, .data +4 B (+12.6%, 3,752 B / 98,304 B, total: 4% used)

k230

• SRAM: .eh_frame +24 B (+0.0%, 1,122,707 B / 268,300,288 B, total: 0% used)

nordic-nrf51822

• FLASH: .text -4 B (-0.0%, 51,904 B / 262,144 B, total: 20% used)

qemu-virt64-aarch64

• Code: .text +16 B (+0.0%, 1,056,388 B)

raspberry-pico-rp2040

• FLASH: .text -8 B (-0.0%, 114,136 B / 2,097,152 B, total: 5% used)

simulator

• Code: .eh_frame +4 B, .rodata -3 B (+0.0%, 2,632,864 B)
• Data: .bss -28 B (-0.0%, 1,582,468 B)

x86

• Code: .text +16 B (+0.0%, 198,333 B)
  No memory changes detected for:
• at32f415-start
• esp32-c3
• hc32f334
• hpmicro-hpm5301evklite
• infineon-psoc6
• loongson-ls1cdev
• nuvoton-m487
• nxp-lpc1114
• renesas-ra2l1
• stm32f407-rt-spark
• stm32l475-atk-pandora-llvm
• wch-ch32v208w-r0
• xuantie-e901plus

[Copilot]

Pull request overview

This PR updates DFS v2 tmpfs and ramfs to avoid silent truncation / overflow risk when handling overlong filenames, by adding explicit length checks and (for ramfs) reusing a dedicated name-parsing helper.

Changes:

• tmpfs: extend _path_separate() to take buffer sizes and return -ENAMETOOLONG when parent/name buffers are insufficient; switch to rt_strncpy.
• ramfs: add _ramfs_set_name() helper to validate/normalize names and return proper errors (e.g., -ENAMETOOLONG) instead of truncating; use rt_strcpy for root name init.
• PR metadata: Title prefix/format and the “BSP/.config/action” verification fields appear incomplete vs repo checklist (English: please consider aligning title prefix to [module][subsystem] lowercase and filling verification info; 中文：建议按仓库规范调整标题前缀为小写 [模块][子系统]，并补充 BSP/.config/action 验证信息)。

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
components/dfs/dfs_v2/filesystems/tmpfs/dfs_tmpfs.c	Add size-aware path splitting to reject overlong filenames; use RT-Thread string APIs.
components/dfs/dfs_v2/filesystems/ramfs/dfs_ramfs.c	Introduce validated name extraction to avoid truncation and reject invalid/overlong names; minor API consistency updates.

[Unbear-Hz]

路径过长时设置错误码，补全未声明的变量