Improve synchronization

- Fix bugs in kDos2Errno definition
- malloc() should now be thread safe
- Fix bug in rollup.com header generator
- Fix open(O_APPEND) on the New Technology
- Fix select() on the New Technology and test it
- Work towards refactoring i/o for thread safety
- Socket reads and writes on NT now poll for signals
- Work towards i/o completion ports on the New Technology
- Make read() and write() intermittently check for signals
- Blinkenlights keyboard i/o so much better on NT w/ poll()
- You can now poll() files and sockets at the same time on NT
- Fix bug in appendr() that manifests with dlmalloc footers off

libc/calls/printfds.c

@@ -0,0 +1,58 @@
+/*-*- 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 2022 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/internal.h"
+#include "libc/intrin/kprintf.h"
+
+static const char *__fdkind2str(int x) {
+  switch (x) {
+    case kFdEmpty:
+      return "kFdEmpty";
+    case kFdFile:
+      return "kFdFile";
+    case kFdSocket:
+      return "kFdSocket";
+    case kFdProcess:
+      return "kFdProcess";
+    case kFdConsole:
+      return "kFdConsole";
+    case kFdSerial:
+      return "kFdSerial";
+    case kFdZip:
+      return "kFdZip";
+    case kFdEpoll:
+      return "kFdEpoll";
+    default:
+      return "kFdWut";
+  }
+}
+
+void __printfds(void) {
+  int i;
+  for (i = 0; i < g_fds.n; ++i) {
+    if (!g_fds.p[i].kind) continue;
+    kprintf("%3d %s", i, __fdkind2str(g_fds.p[i].kind));
+    if (g_fds.p[i].zombie) kprintf(" zombie");
+    if (g_fds.p[i].flags) kprintf(" flags=%#x", g_fds.p[i].flags);
+    if (g_fds.p[i].mode) kprintf(" mode=%#o", g_fds.p[i].mode);
+    if (g_fds.p[i].handle) kprintf(" handle=%ld", g_fds.p[i].handle);
+    if (g_fds.p[i].extra) kprintf(" extra=%ld", g_fds.p[i].extra);
+    if (g_fds.p[i].worker) kprintf(" worker=%p", g_fds.p[i].worker);
+    kprintf("%n", g_fds.p[i].zombie);
+  }
+}