docs: tighten sdk90 tree reference selector notes

AI.md

@@ -1088,4 +1088,26 @@ Latest endpoint audit checkpoint from patch 0249:
 - Do not regroup these two direct create-file cases in a later cleanup; keep the
   per-case Request/Response audit rule intact.
 
-Next patch number should be `0252`.
+## 2026-06-02 - Patch 0252 SDK 90 tree/reference/compression selector notes
+
+- Continued NDK-first after the direct create-file split.  The NDK Enhanced
+  NCP `89/xx` chapter is not taken as the next implementation target here
+  because the `89/01` page is marked `NetWare Servers: 6.5, SP2 and later`;
+  keep those 5.x+/6.x-only enhanced namespace endpoints out of this 1.x-4.x
+  audit unless project scope changes.
+- Audited the first NetWare-4.x-relevant SDK `90/xx` block in `src/nwconn.c`:
+  - `90/00` Parse Tree
+  - `90/10` Get Reference Count from Dir Entry Number
+  - `90/11` Get Reference Count from Dir Handle
+  - `90/12` Set Compressed File Size
+- Each selector already had its own `switch` case; patch `0252` tightens those
+  case-local comments with exact NDK `SubFuncStrucLen`, request fields and
+  response fields.
+- Runtime behavior remains unchanged: all four selectors still return `0xfb`
+  until a real namespace tree/reference-count/compression metadata provider
+  exists.
+- Do not synthesize reference counts or compressed-size replies from partial
+  Unix `stat(2)` state.  These replies require NetWare directory-base identity,
+  namespace handles, reference tracking and compression metadata.
+
+Next patch number should be `0253`.

TODO.md

@@ -1731,8 +1731,25 @@ Current status:
 - Runtime behavior is unchanged; both cases still call `nw_creat_open_file()`
   and return the old file-handle plus `NW_FILE_INFO` response layout.
 
+### SDK 90 tree/reference/compression selector notes
+
+Current status:
+
+- Patch `0252` audits the first NetWare-4.x-relevant SDK `90/xx` block in
+  `src/nwconn.c`:
+  - `90/00` Parse Tree
+  - `90/10` Get Reference Count from Dir Entry Number
+  - `90/11` Get Reference Count from Dir Handle
+  - `90/12` Set Compressed File Size
+- The `89/xx` Enhanced NCP chapter is skipped for this pass because the NDK
+  marks `89/01` as `NetWare Servers: 6.5, SP2 and later`; keep 5.x+/6.x-only
+  enhanced namespace endpoints out of the 1.x-4.x endpoint audit.
+- Runtime behavior is unchanged; the `90/00`, `90/10`, `90/11`, and `90/12`
+  cases still return `0xfb` until a real provider exists.
+
 Follow-up:
 
 - Continue NDK-first with the next documented NetWare 1.x/2.x/3.x endpoint or
-  planned 4.x endpoint that still has grouped or missing case-local
-  Request/Response audit notes.  Skip 5.x-only endpoints.
+  planned 4.x endpoint after `90/12`, likely the Data Migration selector block
+  `90/128..136`, and keep one case-local Request/Response comment per selector.
+  Skip 5.x-only endpoints.

src/nwconn.c

@@ -7328,31 +7328,34 @@ static int handle_ncp_serv(void)
                               ? (int)requestdata[0] : -1;
 
                    switch (dm_sub) {
-                     case 0x00: /* Parse Tree.
-                                 * Request: InformationMask, InformationMask2,
-                                 * reserved, limbCount, limbStruct[].
+                     case 0x00: /* SDK 90/00 Parse Tree.
+                                 * Request: SubFuncStrucLen = 17 + limbStruct,
+                                 * InformationMask, InformationMask2, reserved,
+                                 * limbCount, then limbStruct[].
                                  * Reply: limbCompletedCnt, ItemsCount,
-                                 * nextLimbScanNum, InfoBlock[].
+                                 * nextLimbScanNum, then InfoBlock[].
                                  * Future owner: namespace tree scanner.
                                  */
                                completition = 0xfb;
                                break;
-                     case 0x0a: /* Get Reference Count from Dir Entry Number.
-                                 * Request: Volume, DirBase, NameSpace.
+                     case 0x0a: /* SDK 90/10 Get Reference Count from Dir Entry Number.
+                                 * Request: SubFuncStrucLen = 13, Volume,
+                                 * DirBase, NameSpace.
                                  * Reply: ReferenceCount.
                                  */
                                completition = 0xfb;
                                break;
-                     case 0x0b: /* Get Reference Count from Dir Handle.
-                                 * Request: DirectoryHandle.
+                     case 0x0b: /* SDK 90/11 Get Reference Count from Dir Handle.
+                                 * Request: SubFuncStrucLen = 5,
+                                 * DirectoryHandle.
                                  * Reply: ReferenceCount.
                                  */
                                completition = 0xfb;
                                break;
-                     case 0x0c: /* Set Compressed File Size.
-                                 * Request: file identity plus compressed size
-                                 * fields as documented for SDK 90/12.
-                                 * Reply: no payload; Completion reports status.
+                     case 0x0c: /* SDK 90/12 Set Compressed File Size.
+                                 * Request: SubFuncStrucLen = 11,
+                                 * NetWareFileHandle, SuggestedFileSize.
+                                 * Reply: OldFileSize, NewFileSize.
                                  * Future owner: filesystem/compression metadata.
                                  */
                                completition = 0xfb;