cosmopolitan/libc/runtime/fork-nt.c
Justine Tunney 1422e96b4e
Introduce native support for MacOS ARM64
There's a new program named ape/ape-m1.c which will be used to build an
embeddable binary that can load ape and elf executables. The support is
mostly working so far, but still chasing down ABI issues.
2023-05-20 04:17:03 -07:00

367 lines
13 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/calls/internal.h"
#include "libc/calls/ntspawn.h"
#include "libc/calls/state.internal.h"
#include "libc/calls/syscall-nt.internal.h"
#include "libc/calls/syscall_support-nt.internal.h"
#include "libc/calls/wincrash.internal.h"
#include "libc/errno.h"
#include "libc/fmt/itoa.h"
#include "libc/intrin/atomic.h"
#include "libc/intrin/directmap.internal.h"
#include "libc/intrin/kprintf.h"
#include "libc/intrin/strace.internal.h"
#include "libc/intrin/weaken.h"
#include "libc/macros.internal.h"
#include "libc/mem/alloca.h"
#include "libc/mem/mem.h"
#include "libc/nexgen32e/nt2sysv.h"
#include "libc/nt/console.h"
#include "libc/nt/createfile.h"
#include "libc/nt/enum/accessmask.h"
#include "libc/nt/enum/creationdisposition.h"
#include "libc/nt/enum/fileflagandattributes.h"
#include "libc/nt/enum/filemapflags.h"
#include "libc/nt/enum/pageflags.h"
#include "libc/nt/enum/processcreationflags.h"
#include "libc/nt/enum/startf.h"
#include "libc/nt/ipc.h"
#include "libc/nt/memory.h"
#include "libc/nt/process.h"
#include "libc/nt/runtime.h"
#include "libc/nt/signals.h"
#include "libc/nt/struct/ntexceptionpointers.h"
#include "libc/runtime/internal.h"
#include "libc/runtime/memtrack.internal.h"
#include "libc/runtime/runtime.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/map.h"
#include "libc/sysv/consts/o.h"
#include "libc/sysv/consts/prot.h"
#include "libc/sysv/errfuns.h"
#include "libc/thread/tls.h"
#ifdef __x86_64__
STATIC_YOINK("_check_sigchld");
extern int64_t __wincrashearly;
bool32 __onntconsoleevent_nt(uint32_t);
void kmalloc_unlock(void);
static textwindows wontreturn void AbortFork(const char *func) {
STRACE("fork() %s() failed %d", func, GetLastError());
ExitProcess(177);
}
static textwindows char16_t *ParseInt(char16_t *p, int64_t *x) {
*x = 0;
while (*p == ' ') p++;
while ('0' <= *p && *p <= '9') {
*x *= 10;
*x += *p++ - '0';
}
return p;
}
static inline textwindows ssize_t ForkIo(int64_t h, char *p, size_t n,
bool32 (*f)()) {
size_t i;
uint32_t x;
for (i = 0; i < n; i += x) {
if (!f(h, p + i, n - i, &x, NULL)) {
return __winerr();
}
}
return i;
}
static dontinline textwindows bool ForkIo2(int64_t h, void *buf, size_t n,
bool32 (*fn)(), const char *sf,
bool ischild) {
ssize_t rc = ForkIo(h, buf, n, fn);
if (ischild) __tls_enabled_set(false); // prevent tls crash in kprintf
NTTRACE("%s(%ld, %p, %'zu) → %'zd% m", sf, h, buf, n, rc);
return rc != -1;
}
static dontinline textwindows bool WriteAll(int64_t h, void *buf, size_t n) {
return ForkIo2(h, buf, n, WriteFile, "WriteFile", false);
}
static textwindows dontinline void ReadOrDie(int64_t h, void *buf, size_t n) {
if (!ForkIo2(h, buf, n, ReadFile, "ReadFile", true)) {
AbortFork("ReadFile");
}
}
static textwindows int64_t MapOrDie(uint32_t prot, uint64_t size) {
int64_t h;
if ((h = CreateFileMapping(-1, 0, prot, size >> 32, size, 0))) {
return h;
} else {
AbortFork("MapOrDie");
}
}
static textwindows void ViewOrDie(int64_t h, uint32_t access, size_t pos,
size_t size, void *base) {
void *got;
got = MapViewOfFileEx(h, access, pos >> 32, pos, size, base);
if (!got || (base && got != base)) {
AbortFork("ViewOrDie");
}
}
static textwindows int OnForkCrash(struct NtExceptionPointers *ep) {
kprintf("error: fork() child crashed!%n"
"\tExceptionCode = %#x%n"
"\tRip = %x%n",
ep->ExceptionRecord->ExceptionCode,
ep->ContextRecord ? ep->ContextRecord->Rip : -1);
ExitProcess(73);
}
textwindows void WinMainForked(void) {
bool ok;
jmp_buf jb;
int64_t reader;
char *addr, *shad;
struct DirectMap dm;
uint64_t size, upsize;
int64_t oncrash, savetsc;
struct MemoryInterval *maps;
char16_t fvar[21 + 1 + 21 + 1];
uint32_t i, varlen, oldprot, savepid;
long mapcount, mapcapacity, specialz;
// check to see if the process was actually forked
// this variable should have the pipe handle numba
varlen = GetEnvironmentVariable(u"_FORK", fvar, ARRAYLEN(fvar));
if (!varlen || varlen >= ARRAYLEN(fvar)) return;
NTTRACE("WinMainForked()");
SetEnvironmentVariable(u"_FORK", NULL);
#ifdef SYSDEBUG
oncrash = AddVectoredExceptionHandler(1, NT2SYSV(OnForkCrash));
#endif
ParseInt(fvar, &reader);
// read the cpu state from the parent process & plus
// read the list of mappings from the parent process
// this is stored in a special secretive memory map!
// read ExtendMemoryIntervals for further details :|
maps = (void *)kMemtrackStart;
ReadOrDie(reader, jb, sizeof(jb));
ReadOrDie(reader, &mapcount, sizeof(_mmi.i));
ReadOrDie(reader, &mapcapacity, sizeof(_mmi.n));
specialz = ROUNDUP(mapcapacity * sizeof(_mmi.p[0]), kMemtrackGran);
ViewOrDie(MapOrDie(kNtPageReadwrite, specialz), kNtFileMapWrite, 0, specialz,
maps);
ReadOrDie(reader, maps, mapcount * sizeof(_mmi.p[0]));
if (IsAsan()) {
shad = (char *)(((intptr_t)maps >> 3) + 0x7fff8000);
size = ROUNDUP(specialz >> 3, FRAMESIZE);
ViewOrDie(MapOrDie(kNtPageReadwrite, size), kNtFileMapWrite, 0, size, maps);
ReadOrDie(reader, shad, (mapcount * sizeof(_mmi.p[0])) >> 3);
}
// read the heap mappings from the parent process
for (i = 0; i < mapcount; ++i) {
addr = (char *)((uint64_t)maps[i].x << 16);
size = maps[i].size;
if ((maps[i].flags & MAP_TYPE) != MAP_SHARED) {
upsize = ROUNDUP(size, FRAMESIZE);
// we don't need to close the map handle because sys_mmap_nt
// doesn't mark it inheritable across fork() for MAP_PRIVATE
ViewOrDie((maps[i].h = MapOrDie(kNtPageExecuteReadwrite, upsize)),
kNtFileMapWrite | kNtFileMapExecute, 0, upsize, addr);
ReadOrDie(reader, addr, size);
} else {
// we can however safely inherit MAP_SHARED with zero copy
ViewOrDie(maps[i].h,
maps[i].readonlyfile ? kNtFileMapRead | kNtFileMapExecute
: kNtFileMapWrite | kNtFileMapExecute,
maps[i].offset, size, addr);
}
}
// read the .data and .bss program image sections
savepid = __pid;
savetsc = kStartTsc;
ReadOrDie(reader, __data_start, __data_end - __data_start);
ReadOrDie(reader, __bss_start, __bss_end - __bss_start);
__pid = savepid;
kStartTsc = savetsc;
__threaded = false;
__tls_index = 0;
__tls_enabled_set(false);
// apply fixups and reapply memory protections
_mmi.p = maps;
_mmi.n = specialz / sizeof(_mmi.p[0]);
for (i = 0; i < mapcount; ++i) {
if (!VirtualProtect((void *)((uint64_t)maps[i].x << 16), maps[i].size,
__prot2nt(maps[i].prot, maps[i].iscow), &oldprot)) {
AbortFork("VirtualProtect");
}
}
// mitosis complete
if (!CloseHandle(reader)) {
AbortFork("CloseHandle");
}
// rewrap the stdin named pipe hack
// since the handles closed on fork
struct Fds *fds = VEIL("r", &g_fds);
fds->p[0].handle = GetStdHandle(kNtStdInputHandle);
fds->p[1].handle = GetStdHandle(kNtStdOutputHandle);
fds->p[2].handle = GetStdHandle(kNtStdErrorHandle);
// untrack children of parent since we specify with both
// CreateProcess() and CreateThread() as non-inheritable
for (i = 0; i < fds->n; ++i) {
if (fds->p[i].kind == kFdProcess) {
fds->p[i].kind = 0;
atomic_store_explicit(&fds->f, MIN(i, fds->f), memory_order_relaxed);
}
}
// restore the crash reporting stuff
#ifdef SYSDEBUG
RemoveVectoredExceptionHandler(oncrash);
#endif
if (_weaken(__wincrash_nt)) {
if (!IsTiny()) {
RemoveVectoredExceptionHandler(__wincrashearly);
}
AddVectoredExceptionHandler(1, (void *)_weaken(__wincrash_nt));
}
if (_weaken(__onntconsoleevent_nt)) {
SetConsoleCtrlHandler(_weaken(__onntconsoleevent_nt), 1);
}
// jump back into function below
longjmp(jb, 1);
}
textwindows int sys_fork_nt(uint32_t dwCreationFlags) {
jmp_buf jb;
uint32_t oldprot;
char ok, threaded;
char **args, **args2;
struct CosmoTib *tib;
char16_t pipename[64];
int64_t reader, writer;
struct NtStartupInfo startinfo;
int i, n, pid, untrackpid, rc = -1;
char *p, forkvar[6 + 21 + 1 + 21 + 1];
struct NtProcessInformation procinfo;
threaded = __threaded;
tib = __tls_enabled ? __get_tls() : 0;
if (!setjmp(jb)) {
pid = untrackpid = __reservefd_unlocked(-1);
reader = CreateNamedPipe(CreatePipeName(pipename),
kNtPipeAccessInbound | kNtFileFlagOverlapped,
kNtPipeTypeMessage | kNtPipeReadmodeMessage, 1,
65536, 65536, 0, &kNtIsInheritable);
writer = CreateFile(pipename, kNtGenericWrite, 0, 0, kNtOpenExisting,
kNtFileFlagOverlapped, 0);
if (pid != -1 && reader != -1 && writer != -1) {
p = stpcpy(forkvar, "_FORK=");
p = FormatUint64(p, reader);
bzero(&startinfo, sizeof(startinfo));
startinfo.cb = sizeof(struct NtStartupInfo);
startinfo.dwFlags = kNtStartfUsestdhandles;
startinfo.hStdInput = __getfdhandleactual(0);
startinfo.hStdOutput = __getfdhandleactual(1);
startinfo.hStdError = __getfdhandleactual(2);
args = __argv;
#ifdef SYSDEBUG
// If --strace was passed to this program, then propagate it the
// forked process since the flag was removed by __intercept_flag
if (strace_enabled(0) > 0) {
for (n = 0; args[n];) ++n;
args2 = alloca((n + 2) * sizeof(char *));
for (i = 0; i < n; ++i) args2[i] = args[i];
args2[i++] = "--strace";
args2[i] = 0;
args = args2;
}
#endif
if (ntspawn(GetProgramExecutableName(), args, environ, forkvar, 0, 0,
true, dwCreationFlags, 0, &startinfo, &procinfo) != -1) {
CloseHandle(procinfo.hThread);
ok = WriteAll(writer, jb, sizeof(jb)) &&
WriteAll(writer, &_mmi.i, sizeof(_mmi.i)) &&
WriteAll(writer, &_mmi.n, sizeof(_mmi.n)) &&
WriteAll(writer, _mmi.p, _mmi.i * sizeof(_mmi.p[0]));
if (IsAsan() && ok) {
ok = WriteAll(writer, (char *)(((intptr_t)_mmi.p >> 3) + 0x7fff8000),
(_mmi.i * sizeof(_mmi.p[0])) >> 3);
}
for (i = 0; i < _mmi.i && ok; ++i) {
if ((_mmi.p[i].flags & MAP_TYPE) != MAP_SHARED) {
ok = WriteAll(writer, (void *)((uint64_t)_mmi.p[i].x << 16),
_mmi.p[i].size);
}
}
if (ok) ok = WriteAll(writer, __data_start, __data_end - __data_start);
if (ok) ok = WriteAll(writer, __bss_start, __bss_end - __bss_start);
if (ok) {
if (!CloseHandle(writer)) ok = false;
writer = -1;
}
if (ok) {
g_fds.p[pid].kind = kFdProcess;
g_fds.p[pid].handle = procinfo.hProcess;
g_fds.p[pid].flags = O_CLOEXEC;
g_fds.p[pid].zombie = false;
untrackpid = -1;
rc = pid;
} else {
TerminateProcess(procinfo.hProcess, 127);
CloseHandle(procinfo.hProcess);
}
}
}
if (reader != -1) CloseHandle(reader);
if (writer != -1) CloseHandle(writer);
if (rc == -1 && errno != ENOMEM) {
eagain(); // posix fork() only specifies two errors
}
} else {
rc = 0;
if (tib && _weaken(__set_tls) && _weaken(__morph_tls)) {
_weaken(__set_tls)(tib);
_weaken(__morph_tls)();
__tls_enabled_set(true);
}
if (threaded && !__threaded && _weaken(__enable_threads)) {
_weaken(__enable_threads)();
}
}
if (untrackpid != -1) {
__releasefd(untrackpid);
}
return rc;
}
#endif /* __x86_64__ */