Make minor improvements

- Work towards simplifying ape.S startup process
- Rewrote ar because it took minutes to build cosmopolitan.a

libc/calls/getdomainname.c

@@ -0,0 +1,53 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2020 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ This program is free software; you can redistribute it and/or modify         │
+│ it under the terms of the GNU General Public License as published by         │
+│ the Free Software Foundation; version 2 of the License.                      │
+│                                                                              │
+│ This program is distributed in the hope that it will be useful, but          │
+│ WITHOUT ANY WARRANTY; without even the implied warranty of                   │
+│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU             │
+│ General Public License for more details.                                     │
+│                                                                              │
+│ You should have received a copy of the GNU General Public License            │
+│ along with this program; if not, write to the Free Software                  │
+│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA                │
+│ 02110-1301 USA                                                               │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/calls.h"
+#include "libc/calls/internal.h"
+#include "libc/calls/struct/utsname.h"
+#include "libc/dce.h"
+#include "libc/macros.h"
+#include "libc/nt/enum/computernameformat.h"
+#include "libc/nt/errors.h"
+#include "libc/nt/runtime.h"
+#include "libc/nt/systeminfo.h"
+#include "libc/str/str.h"
+#include "libc/sysv/errfuns.h"
+
+int getdomainname(char *name, size_t len) {
+  uint32_t nSize;
+  char16_t name16[256];
+  struct utsname u;
+  if (len < 1) return einval();
+  if (!name) return efault();
+  if (!IsWindows()) {
+    if (uname(&u) == -1) return -1;
+    if (!memccpy(name, u.domainname[0] ? u.domainname : u.nodename, '\0',
+                 len)) {
+      name[len - 1] = '\0';
+    }
+    return 0;
+  } else {
+    nSize = ARRAYLEN(name16);
+    if (!GetComputerNameEx(kNtComputerNameDnsFullyQualified, name16, &nSize)) {
+      return winerr();
+    }
+    tprecode16to8(name, MIN(MIN(ARRAYLEN(name16), nSize + 1), len), name16);
+    return 0;
+  }
+}