Make fixes and improvements

- Introduce __assert_disable global
- Improve strsignal() thread safety
- Make system call tracing thread safe
- Fix SO_RCVTIMEO / SO_SNDTIMEO on Windows
- Refactor DescribeFoo() functions into one place
- Fix fork() on Windows when TLS and MAP_STACK exist
- Round upwards in setsockopt(SO_RCVTIMEO) on Windows
- Disable futexes on OpenBSD which seem extremely broken
- Implement a better kludge for monotonic time on Windows

libc/intrin/ksignalnames.S

@@ -0,0 +1,71 @@
+/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8     -*-│
+│vi: set et ft=asm ts=8 tw=8 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/fmt/magnumstrs.internal.h"
+#include "libc/macros.internal.h"
+
+	.macro	.e e s
+	.long	\e - kSignalNames
+	.long	1f - kSignalNames
+	.rodata.str1.1
+1:	.string	"\s"
+	.previous
+	.endm
+
+	.section .rodata
+	.align 4
+	.underrun
+kSignalNames:
+	.e	SIGHUP,"SIGHUP"
+	.e	SIGINT,"SIGINT"
+	.e	SIGQUIT,"SIGQUIT"
+	.e	SIGILL,"SIGILL"
+	.e	SIGTRAP,"SIGTRAP"
+	.e	SIGABRT,"SIGABRT"
+	.e	SIGBUS,"SIGBUS"
+	.e	SIGFPE,"SIGFPE"
+	.e	SIGKILL,"SIGKILL"
+	.e	SIGUSR1,"SIGUSR1"
+	.e	SIGSEGV,"SIGSEGV"
+	.e	SIGUSR2,"SIGUSR2"
+	.e	SIGPIPE,"SIGPIPE"
+	.e	SIGALRM,"SIGALRM"
+	.e	SIGTERM,"SIGTERM"
+	.e	SIGSTKFLT,"SIGSTKFLT"
+	.e	SIGCHLD,"SIGCHLD"
+	.e	SIGCONT,"SIGCONT"
+	.e	SIGSTOP,"SIGSTOP"
+	.e	SIGTSTP,"SIGTSTP"
+	.e	SIGTTIN,"SIGTTIN"
+	.e	SIGTTOU,"SIGTTOU"
+	.e	SIGURG,"SIGURG"
+	.e	SIGXCPU,"SIGXCPU"
+	.e	SIGXFSZ,"SIGXFSZ"
+	.e	SIGVTALRM,"SIGVTALRM"
+	.e	SIGPROF,"SIGPROF"
+	.e	SIGWINCH,"SIGWINCH"
+	.e	SIGIO,"SIGIO"
+	.e	SIGSYS,"SIGSYS"
+	.e	SIGINFO,"SIGINFO"
+	.e	SIGRTMAX,"SIGRTMAX"
+	.e	SIGRTMIN,"SIGRTMIN"
+	.e	SIGEMT,"SIGEMT"
+	.e	SIGPWR,"SIGPWR"
+	.long	MAGNUM_TERMINATOR
+	.endobj	kSignalNames,globl,hidden
+	.overrun