cosmopolitan/libc/calls/now.c
Justine Tunney b107d2709f Add /statusz page to redbean plus other enhancements
redbean improvements:

- Explicitly disable corking
- Simulate Python regex API for Lua
- Send warmup requests in main process on startup
- Add Class-A granular IPv4 network classification
- Add /statusz page so you can monitor your redbean's health
- Fix regressions on OpenBSD/NetBSD caused by recent changes
- Plug Authorization header into Lua GetUser and GetPass APIs
- Recognize X-Forwarded-{For,Host} from local reverse proxies
- Add many additional functions to redbean Lua server page API
- Report resource usage of child processes on `/` listing page
- Introduce `-a` flag for logging child process resource usage
- Introduce `-t MILLIS` flag and `ProgramTimeout(ms)` init API
- Introduce `-H "Header: value"` flag and `ProgramHeader(k,v)` API

Cosmopolitan Libc improvements:

- Make strerror() simpler
- Make inet_pton() not depend on sscanf()
- Fix OpenExecutable() which broke .data section earlier
- Fix stdio in cases where it overflows kernel tty buffer
- Fix bugs in crash reporting w/o .com.dbg binary present
- Add polyfills for SO_LINGER, SO_RCVTIMEO, and SO_SNDTIMEO
- Polyfill TCP_CORK on BSD and XNU using TCP_NOPUSH magnums

New netcat clone in examples/nc.c:

While testing some of the failure conditions for redbean, I noticed that
BusyBox's `nc` command is pretty busted, if you use it as an interactive
tool, rather than having it be part of a pipeline. Unfortunately this'll
only work on UNIX since Windows doesn't let us poll on stdio and sockets
at the same time because I don't think they want tools like this running
on their platform. So if you want forbidden fruit, it's here so enjoy it
2021-04-23 18:53:57 -07:00

86 lines
3.4 KiB
C

/*-*- 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 │
│ │
│ 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/bits/bits.h"
#include "libc/bits/initializer.internal.h"
#include "libc/bits/safemacros.internal.h"
#include "libc/calls/calls.h"
#include "libc/dce.h"
#include "libc/macros.internal.h"
#include "libc/nexgen32e/rdtsc.h"
#include "libc/nexgen32e/x86feature.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/clock.h"
#include "libc/time/time.h"
static struct Now {
bool once;
uint64_t k0;
long double r0, cpn;
} g_now;
static long double GetTimeSample(void) {
uint64_t tick1, tick2;
long double time1, time2;
sched_yield();
time1 = dtime(CLOCK_MONOTONIC);
tick1 = rdtsc();
nanosleep(&(struct timespec){0, 100000}, NULL);
time2 = dtime(CLOCK_MONOTONIC);
tick2 = rdtsc();
return (time2 - time1) * 1e9 / MAX(1, tick2 - tick1);
}
static long double MeasureNanosPerCycle(void) {
int i;
long double avg, samp;
for (avg = 1.0L, i = 1; i < 5; ++i) {
samp = GetTimeSample();
avg += (samp - avg) / i;
}
return avg;
}
void RefreshTime(void) {
struct Now now;
now.cpn = MeasureNanosPerCycle();
now.r0 = dtime(CLOCK_REALTIME);
now.k0 = rdtsc();
now.once = true;
memcpy(&g_now, &now, sizeof(now));
}
long double ConvertTicksToNanos(uint64_t ticks) {
if (!g_now.once) RefreshTime();
return ticks * g_now.cpn; /* pico scale */
}
static long double ConvertTicksToSeconds(uint64_t ticks) {
return 1 / 1e9 * ConvertTicksToNanos(ticks);
}
long double nowl_sys(void) {
return dtime(CLOCK_REALTIME);
}
long double nowl_art(void) {
uint64_t ticks;
if (!g_now.once) RefreshTime();
ticks = unsignedsubtract(rdtsc(), g_now.k0);
return g_now.r0 + ConvertTicksToSeconds(ticks);
}