Check for EINTR in poll$nt()

This is a bandaid that lets CTRL-C work in daemons until a better
solution for signals on Windows can be implemented.

libc/calls/g_sighandrvas.c

@@ -18,4 +18,4 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/internal.h"
 
-hidden int g_sighandrvas[NSIG];
+unsigned __sighandrvas[NSIG];

libc/calls/hefty/fork-nt.c

@@ -141,8 +141,8 @@ textwindows int fork$nt(void) {
                   &startinfo, &procinfo) != -1) {
         CloseHandle(reader);
         CloseHandle(procinfo.hThread);
-        if (weaken(g_sighandrvas) &&
-            weaken(g_sighandrvas)[SIGCHLD] == SIG_IGN) {
+        if (weaken(__sighandrvas) &&
+            weaken(__sighandrvas)[SIGCHLD] == SIG_IGN) {
           CloseHandle(procinfo.hProcess);
         } else {
           g_fds.p[pid].kind = kFdProcess;

libc/calls/internal.h

@@ -60,8 +60,9 @@ struct Fds {
 
 extern const struct Fd kEmptyFd;
 
+hidden extern volatile bool __interrupted;
 hidden extern int __vforked;
-hidden extern int g_sighandrvas[NSIG];
+hidden extern unsigned __sighandrvas[NSIG];
 hidden extern struct Fds g_fds;
 hidden extern struct NtSystemInfo g_ntsysteminfo;
 hidden extern struct NtStartupInfo g_ntstartupinfo;

libc/calls/interrupted.c

@@ -0,0 +1,21 @@
+/*-*- 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 2021 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"
+
+volatile bool __interrupted;

libc/calls/onntconsoleevent.c

@@ -19,12 +19,15 @@
 #include "libc/bits/pushpop.h"
 #include "libc/calls/internal.h"
 #include "libc/calls/struct/siginfo.h"
+#include "libc/calls/typedef/sigaction_f.h"
 #include "libc/nt/enum/ctrlevent.h"
+#include "libc/nt/runtime.h"
 #include "libc/str/str.h"
 #include "libc/sysv/consts/sig.h"
 
 textwindows bool32 __onntconsoleevent(uint32_t CtrlType) {
   int sig;
+  unsigned rva;
   siginfo_t info;
   switch (CtrlType) {
     case kNtCtrlCEvent:
@@ -43,8 +46,19 @@ textwindows bool32 __onntconsoleevent(uint32_t CtrlType) {
     default:
       return false;
   }
-  memset(&info, 0, sizeof(info));
-  info.si_signo = sig;
-  __sigenter(sig, &info, NULL);
-  return true;
+  switch ((rva = __sighandrvas[sig])) {
+    case (uintptr_t)SIG_DFL:
+      dprintf(2, "__onntconsoleevent ExitProcess\n");
+      ExitProcess(128 + sig);
+    case (uintptr_t)SIG_IGN:
+      dprintf(2, "__onntconsoleevent SIG_IGN\n");
+      return true;
+    default:
+      dprintf(2, "__onntconsoleevent %#x\n", rva);
+      memset(&info, 0, sizeof(info));
+      info.si_signo = sig;
+      ((sigaction_f)(_base + rva))(sig, &info, NULL);
+      __interrupted = true;
+      return true;
+  }
 }

libc/calls/sigaction.c

@@ -179,12 +179,12 @@ int(sigaction)(int sig, const struct sigaction *act, struct sigaction *oldact) {
   }
   if (rc != -1) {
     if (oldact) {
-      oldrva = g_sighandrvas[sig];
+      oldrva = __sighandrvas[sig];
       oldact->sa_sigaction = (sigaction_f)(
           oldrva < kSigactionMinRva ? oldrva : (intptr_t)&_base + oldrva);
     }
     if (act) {
-      g_sighandrvas[sig] = rva;
+      __sighandrvas[sig] = rva;
     }
   }
   return rc;

libc/calls/sigenter.S

@@ -35,7 +35,7 @@ __sigenter:
 	mov	%rsp,%rbp
 	.profilable
 	and	$NSIG-1,%edi
-	mov	g_sighandrvas(,%rdi,4),%eax
+	mov	__sighandrvas(,%rdi,4),%eax
 	cmp	$kSigactionMinRva,%eax
 	jl	2f
 	lea	_base(%rax),%eax

libc/sock/poll-nt.c

@@ -16,6 +16,7 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/bits/bits.h"
 #include "libc/calls/internal.h"
 #include "libc/macros.h"
 #include "libc/nt/struct/pollfd.h"
@@ -37,6 +38,7 @@ textwindows int poll$nt(struct pollfd *fds, uint64_t nfds, uint64_t timeoutms) {
     ntfds[i].events = fds[i].events & (POLLPRI | POLLIN | POLLOUT);
   }
   for (;;) {
+    if (cmpxchg(&__interrupted, true, false)) return eintr();
     waitfor = MIN(1000, timeoutms); /* for ctrl+c */
     if ((got = WSAPoll(ntfds, nfds, waitfor)) != -1) {
       if (!got && (timeoutms -= waitfor)) continue;

tool/build/runitd.c

@@ -98,11 +98,16 @@
 #define kLogMaxBytes (2 * 1000 * 1000)
 
 char *g_exepath;
+volatile bool g_interrupted;
 struct sockaddr_in g_servaddr;
 unsigned char g_buf[PAGESIZE];
 bool g_daemonize, g_sendready;
 int g_timeout, g_devnullfd, g_servfd, g_clifd, g_exefd;
 
+void OnInterrupt(int sig) {
+  g_interrupted = true;
+}
+
 void OnChildTerminated(int sig) {
   int ws, pid;
   for (;;) {
@@ -359,6 +364,7 @@ int Poll(void) {
   int i, wait, evcount;
   struct pollfd fds[1];
 TryAgain:
+  if (g_interrupted) return 0;
   fds[0].fd = g_servfd;
   fds[0].events = POLLIN;
   wait = MIN(1000, g_timeout);
@@ -377,12 +383,14 @@ int Poll(void) {
 
 int Serve(void) {
   StartTcpServer();
+  sigaction(SIGINT, (&(struct sigaction){.sa_handler = (void *)OnInterrupt}),
+            NULL);
   sigaction(SIGCHLD,
             (&(struct sigaction){.sa_handler = (void *)OnChildTerminated,
                                  .sa_flags = SA_RESTART}),
             NULL);
   for (;;) {
-    if (!Poll() && !g_timeout) break;
+    if (!Poll() && (!g_timeout || g_interrupted)) break;
   }
   close(g_servfd);
   LOGF("timeout expired, shutting down");