win32: changes to user ids

Formalise the use of 0 as the uid of a process running with elevated
privileges:

- Rewrite getuid(2) to return DEFAULT_UID by default and 0 if the
  process has elevated privileges.
- geteuid(2) and the corresponding functions for groups are aliases
  for getuid(2).
- Change root's home directory to be whatever GetSystemDirectory()
  returns, probably C:/Windows/System32 in most cases.
- Remove the special handling of geteuid(2) in the line editing code.

With these changes the shell started by 'su' is a lot more like a
*nix root shell.

1 files changed, 5 insertions, 3 deletions

diff --git a/loginutils/suw32.c b/loginutils/suw32.c
index 787bcbbef..6396a7b88 100644
--- a/loginutils/suw32.c
+++ b/loginutils/suw32.c
@@ -47,10 +47,12 @@ int suw32_main(int argc UNUSED_PARAM, char **argv)
         /* info.hwnd = NULL; */
         info.lpVerb = "runas";
         info.lpFile = bb_path;
-        /* ShellExecuteEx() always runs system binaries in C:\Windows\System32.
-         * Pass the directory we want to the shell. */
+        /* It seems that when ShellExecuteEx() runs binaries residing in
+         * certain 'system' directories it sets the current directory of
+         * the process to %SYSTEMROOT%\System32.  Override this by passing
+         * the directory we want to the shell. */
         info.lpParameters =
-                xasprintf("--busybox ash -d \"%s\" -t \"BusyBox ash (su)\" ",
+                xasprintf("--busybox ash -d \"%s\" -t \"BusyBox ash (Admin)\" ",
                                         getcwd(NULL, 0));
         if (opt_command)
                 info.lpParameters =