cosmopolitan/libc/calls/prctl.c
Justine Tunney 853b6c3864 Improve system calls
- Wrap clock_getres()
- Wrap sched_setscheduler()
- Make sleep() api conformant
- Polyfill sleep() using select()
- Improve clock_gettime() polyfill
- Make nanosleep() POSIX conformant
- Slightly improve some DNS functions
- Further strengthen pledge() sandboxing
- Improve rounding of timeval / timespec
- Allow layering of pledge() calls on Linux
- Polyfill sched_yield() using select() on XNU
- Delete more system constants we probably don't need
2022-07-08 06:42:03 -07:00

55 lines
2.7 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 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/calls.h"
#include "libc/calls/strace.internal.h"
#include "libc/errno.h"
#include "libc/intrin/describeflags.internal.h"
#include "libc/sysv/consts/pr.h"
#include "libc/sysv/errfuns.h"
/**
* Tunes process on Linux.
*
* @raise ENOSYS on non-Linux
*/
privileged int prctl(int operation, ...) {
int rc;
va_list va;
intptr_t a, b;
register intptr_t c asm("r10");
register intptr_t d asm("r8");
va_start(va, operation);
a = va_arg(va, intptr_t);
b = va_arg(va, intptr_t);
c = va_arg(va, intptr_t);
d = va_arg(va, intptr_t);
va_end(va);
if (IsLinux()) {
asm volatile("syscall"
: "=a"(rc)
: "0"(157), "D"(operation), "S"(a), "d"(b), "r"(c), "r"(d)
: "rcx", "r11", "memory");
if (rc > -4096u) errno = -rc, rc = -1;
} else {
rc = enosys();
}
STRACE("prctl(%s, %p, %p, %p, %p) → %d% m", DescribePrctlOperation(operation),
a, b, c, d, rc);
return rc;
}