cosmopolitan/libc/runtime/cosmo2.c
Justine Tunney 791f79fcb3
Make improvements
- We now serialize the file descriptor table when spawning / executing
  processes on Windows. This means you can now inherit more stuff than
  just standard i/o. It's needed by bash, which duplicates the console
  to file descriptor #255. We also now do a better job serializing the
  environment variables, so you're less likely to encounter E2BIG when
  using your bash shell. We also no longer coerce environ to uppercase

- execve() on Windows now remotely controls its parent process to make
  them spawn a replacement for itself. Then it'll be able to terminate
  immediately once the spawn succeeds, without having to linger around
  for the lifetime as a shell process for proxying the exit code. When
  process worker thread running in the parent sees the child die, it's
  given a handle to the new child, to replace it in the process table.

- execve() and posix_spawn() on Windows will now provide CreateProcess
  an explicit handle list. This allows us to remove handle locks which
  enables better fork/spawn concurrency, with seriously correct thread
  safety. Other codebases like Go use the same technique. On the other
  hand fork() still favors the conventional WIN32 inheritence approach
  which can be a little bit messy, but is *controlled* by guaranteeing
  perfectly clean slates at both the spawning and execution boundaries

- sigset_t is now 64 bits. Having it be 128 bits was a mistake because
  there's no reason to use that and it's only supported by FreeBSD. By
  using the system word size, signal mask manipulation on Windows goes
  very fast. Furthermore @asyncsignalsafe funcs have been rewritten on
  Windows to take advantage of signal masking, now that it's much more
  pleasant to use.

- All the overlapped i/o code on Windows has been rewritten for pretty
  good signal and cancelation safety. We're now able to ensure overlap
  data structures are cleaned up so long as you don't longjmp() out of
  out of a signal handler that interrupted an i/o operation. Latencies
  are also improved thanks to the removal of lots of "busy wait" code.
  Waits should be optimal for everything except poll(), which shall be
  the last and final demon we slay in the win32 i/o horror show.

- getrusage() on Windows is now able to report RUSAGE_CHILDREN as well
  as RUSAGE_SELF, thanks to aggregation in the process manager thread.
2023-10-08 08:59:53 -07:00

180 lines
5.9 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 2023 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/struct/rlimit.h"
#include "libc/calls/syscall-sysv.internal.h"
#include "libc/dce.h"
#include "libc/errno.h"
#include "libc/intrin/strace.internal.h"
#include "libc/limits.h"
#include "libc/macros.internal.h"
#include "libc/nexgen32e/rdtsc.h"
#include "libc/runtime/internal.h"
#include "libc/runtime/memtrack.internal.h"
#include "libc/runtime/runtime.h"
#include "libc/runtime/stack.h"
#include "libc/runtime/syslib.internal.h"
#include "libc/sysv/consts/auxv.h"
#include "libc/sysv/consts/map.h"
#include "libc/sysv/consts/nr.h"
#include "libc/sysv/consts/prot.h"
#include "libc/sysv/consts/rlim.h"
#include "libc/sysv/consts/rlimit.h"
#include "libc/sysv/consts/sig.h"
#include "libc/thread/thread.h"
#include "libc/thread/tls.h"
#include "third_party/lua/lunix.h"
#ifndef __x86_64__
/**
* @fileoverview Cosmopolitan C Runtime, Second Edition
*/
int main(int, char **, char **) __attribute__((__weak__));
typedef int init_f(int argc, char **argv, char **envp, unsigned long *auxv);
extern long syscon_start[];
extern long syscon_end[];
extern char syscon_linux[];
extern char syscon_xnu[];
extern char syscon_freebsd[];
extern char syscon_openbsd[];
extern char syscon_netbsd[];
extern char syscon_windows[];
extern init_f __strace_init;
extern init_f *__preinit_array_start[] __attribute__((__weak__));
extern init_f *__preinit_array_end[] __attribute__((__weak__));
extern init_f *__init_array_start[] __attribute__((__weak__));
extern init_f *__init_array_end[] __attribute__((__weak__));
extern char ape_stack_prot[] __attribute__((__weak__));
extern pthread_mutex_t __mmi_lock_obj;
extern int hostos asm("__hostos");
static const char *DecodeMagnum(const char *p, long *r) {
int k = 0;
unsigned long c, x = 0;
do {
c = *p++;
x |= (c & 127) << k;
k += 7;
} while (c & 128);
return *r = x, p;
}
wontreturn textstartup void cosmo(long *sp, struct Syslib *m1) {
// get startup timestamp as early as possible
// its used by --strace and also kprintf() %T
kStartTsc = rdtsc();
// enable enough tls to survive until it can be allocated properly
struct CosmoTib tib = {
.tib_self = &tib,
.tib_self2 = &tib,
.tib_sigmask = -1,
.tib_sigstack_size = 57344,
.tib_sigstack_addr = (char *)__builtin_frame_address(0) - 57344,
.tib_tid = 1,
};
__set_tls(&tib);
// extracts arguments from old sysv stack abi
int argc = *sp;
char **argv = (char **)(sp + 1);
char **envp = (char **)(sp + 1 + argc + 1);
unsigned long *auxv = (unsigned long *)(sp + 1 + argc + 1);
while (*auxv++) donothing;
// set helpful globals
__argc = argc;
__argv = argv;
__envp = envp;
__auxv = auxv;
environ = envp;
program_invocation_name = argv[0];
__oldstack = (intptr_t)sp;
// detect apple m1 environment
const char *magnums;
if (SupportsXnu() && (__syslib = m1)) {
hostos = _HOSTXNU;
magnums = syscon_xnu;
} else if (SupportsLinux()) {
hostos = _HOSTLINUX;
magnums = syscon_linux;
} else {
notpossible;
}
// setup system magic numbers
for (long *mp = syscon_start; mp < syscon_end; ++mp) {
magnums = DecodeMagnum(magnums, mp);
}
// check system call abi compatibility
if (SupportsXnu() && __syslib && __syslib->__version < SYSLIB_VERSION) {
sys_write(2, "need newer ape loader\n", 22);
_Exit(127);
}
// disable enosys trapping
if (IsBsd()) {
void *act[6] = {SIG_IGN};
sys_sigaction(SIGSYS, act, 0, 8, 0);
}
// needed by kisdangerous()
__pid = sys_getpid().ax;
// initialize memory manager
_mmi.i = 0;
_mmi.p = _mmi.s;
_mmi.n = ARRAYLEN(_mmi.s);
__virtualmax = -1;
// initialize file system
__init_fds(argc, argv, envp);
__enable_tls();
#if 0
#if IsAsan()
// TODO(jart): Figure out ASAN data model on AARCH64.
__asan_init(argc, argv, envp, auxv);
#endif
#endif
_init();
// initialize program
#ifdef SYSDEBUG
argc = __strace_init(argc, argv, envp, auxv);
#endif
for (init_f **fp = __init_array_end; fp-- > __init_array_start;) {
(*fp)(argc, argv, envp, auxv);
}
#ifdef FTRACE
argc = ftrace_init();
#endif
// run program
exit(main(argc, argv, envp));
}
#endif /* __x86_64__ */