emacs-27 a10254d: Fix accessing files on networked drives on MS-Windows

[Eli Zaretskii]

branch: emacs-27
commit a10254dd46da920d14dd990714d0f21fd508d07d
Author: Eli Zaretskii <address@hidden>
Commit: Eli Zaretskii <address@hidden>

    Fix accessing files on networked drives on MS-Windows
    
    * src/w32.c (acl_get_file): Set errno to ENOTSUP if
    get_file_security returns ERROR_NOT_SUPPORTED.  (Bug#41463)
---
 src/w32.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/w32.c b/src/w32.c
index 62c53fd..78e75f0 100644
--- a/src/w32.c
+++ b/src/w32.c
@@ -6398,7 +6398,15 @@ acl_get_file (const char *fname, acl_type_t type)
              if (!get_file_security (fname, si, psd, sd_len, &sd_len))
                {
                  xfree (psd);
-                 errno = EIO;
+                 err = GetLastError ();
+                 if (err == ERROR_NOT_SUPPORTED)
+                   errno = ENOTSUP;
+                 else if (err == ERROR_FILE_NOT_FOUND
+                          || err == ERROR_PATH_NOT_FOUND
+                          || err == ERROR_INVALID_NAME)
+                   errno = ENOENT;
+                 else
+                   errno = EIO;
                  psd = NULL;
                }
            }
@@ -6409,6 +6417,8 @@ acl_get_file (const char *fname, acl_type_t type)
                      be encoded in the current ANSI codepage. */
                   || err == ERROR_INVALID_NAME)
            errno = ENOENT;
+         else if (err == ERROR_NOT_SUPPORTED)
+           errno = ENOTSUP;
          else
            errno = EIO;
        }