nwconn: implement AFP entry id from NetWare handle

Wire NCP 0x23/0x06 AFP Get Entry ID From NetWare Handle to the existing AFP entry-id backend.

The WebSDK documents NCP 0x2222/35/06 as taking a 6-byte NetWare file handle and returning the volume number, a 32-bit AFP Entry ID, and a fork indicator. The SDK headers expose the same operation as AFPGetEntryIDFromNetWareHandle() and NWAFPGetEntryIDFromNetWareHandle().

Use the connection-local mars_nwe file handle table to map the supplied NetWare file handle back to its Unix path, require the optional libatalk backend as for the other AFP calls, and then return a libatalk Entry ID when available or the existing stat-derived fallback ID otherwise. Report the data fork for now because mars_nwe does not yet expose AFP resource-fork open semantics.

Extend the Linux AFP entry-id smoke test with --from-handle. The test opens the requested file through libncp in the same connection, sends the returned 6-byte NetWare file handle to the AFP call, and closes the file afterwards.

This implements the read-only data-fork handle-to-entry-id path; persistent CNID mapping and resource-fork handle semantics remain future work.

src/nwconn.c

@@ -450,6 +450,20 @@ static int afp_request_offset(void)
   return(0);
 }
 
+
+static int afp_volume_from_unixname(const char *unixname)
+{
+  int k;
+
+  if (!unixname) return(-1);
+  for (k = 0; k < used_nw_volumes; k++) {
+    int len = nw_volumes[k].unixnamlen;
+    if (len > 0 && !strncmp(unixname, (char *)nw_volumes[k].unixname, len))
+      return(k);
+  }
+  return(-1);
+}
+
 static uint32 afp_fallback_entry_id(int volume, const struct stat *stb)
 /*
  * Build a stable local AFP entry id from Unix identity data when libatalk has
@@ -544,6 +558,59 @@ static int afp_get_entry_id_from_name(uint8 *afp_req, int afp_len,
   return(4);
 }
 
+
+static int afp_get_entry_id_from_netware_handle(uint8 *afp_req, int afp_len,
+                                                uint8 *response)
+{
+  uint32 fhandle;
+  uint8 *unixname;
+  int volume;
+  struct stat stbuff;
+  uint32 entry_id = 0;
+  int result;
+
+  if (afp_len < 7) {
+    XDPRINTF((2,0, "AFP Get Entry ID From NetWare Handle rejected: short request len=%d",
+              afp_len));
+    return(-0x7e); /* NCP Boundary Check Failed */
+  }
+
+  fhandle = GET_32(afp_req + 3); /* bytes 1..2 are the extended handle */
+  unixname = file_get_unix_name(fhandle);
+  if (!unixname) {
+    XDPRINTF((2,0, "AFP Get Entry ID From NetWare Handle rejected: bad handle=%u",
+              fhandle));
+    return(-0x88); /* Invalid File Handle */
+  }
+
+  if (!nwatalk_backend_available()) {
+    XDPRINTF((3,0, "AFP Get Entry ID From NetWare Handle rejected: libatalk backend unavailable"));
+    return(-0xbf); /* invalid namespace */
+  }
+
+  if (stat((char *)unixname, &stbuff)) {
+    XDPRINTF((2,0, "AFP Get Entry ID From NetWare Handle stat failed: handle=%u unix='%s' errno=%d",
+              fhandle, unixname, errno));
+    return(-0x88); /* Invalid File Handle */
+  }
+
+  volume = afp_volume_from_unixname((char *)unixname);
+  if (volume < 0) volume = 0;
+
+  result = nwatalk_get_entry_id((char *)unixname, &entry_id);
+  if (result < 0 || !entry_id)
+    entry_id = afp_fallback_entry_id(volume, &stbuff);
+
+  response[0] = (uint8)volume;
+  U32_TO_BE32(entry_id, response + 1);
+  response[5] = 0; /* data fork */
+
+  XDPRINTF((3,0, "AFP Get Entry ID From NetWare Handle: handle=%u volume=%d unix='%s' entry=0x%08x%s",
+            fhandle, volume, unixname, entry_id,
+            (result < 0) ? " fallback" : ""));
+  return(6);
+}
+
 static int afp_get_entry_id_from_path_name(uint8 *afp_req, int afp_len,
                                            uint8 *response)
 {
@@ -2900,8 +2967,10 @@ static int handle_ncp_serv(void)
                      * Get Entry ID From Name call accepts a volume/base AFP ID
                      * plus a modifying path string; until persistent CNID/base
                      * lookup exists, support the same path-backed SYS:-style
-                     * smoke-test subset.  Then expose the
-                     * read-only AFP Get File Information query for the same
+                     * smoke-test subset.  Get Entry ID From NetWare Handle
+                     * maps an already-open mars_nwe file handle back to its
+                     * Unix path and returns the corresponding AFP ID.  Then expose
+                     * the read-only AFP Get File Information query for the same
                      * SYS:-style path inputs.  AFP 2.0 Get File Information
                      * uses the same request/reply layout for this read-only
                      * path-backed subset, so route it through the same helper
@@ -2915,6 +2984,11 @@ static int handle_ncp_serv(void)
                                            afp_len, responsedata);
                       if (result > -1) data_len = result;
                       else completition = (uint8)-result;
+                    } else if (ufunc == 0x06) {
+                      int result = afp_get_entry_id_from_netware_handle(afp_req,
+                                           afp_len, responsedata);
+                      if (result > -1) data_len = result;
+                      else completition = (uint8)-result;
                     } else if (ufunc == 0x0c) {
                       int result = afp_get_entry_id_from_path_name(afp_req,
                                            afp_len, responsedata);