Fix --ftrace on Windows

libc/calls/finddebugbinary.c

@@ -26,11 +26,11 @@
 #include "libc/elf/def.h"
 #include "libc/elf/tinyelf.internal.h"
 #include "libc/errno.h"
-#include "libc/serialize.h"
 #include "libc/intrin/directmap.internal.h"
 #include "libc/nt/memory.h"
 #include "libc/nt/runtime.h"
 #include "libc/runtime/runtime.h"
+#include "libc/serialize.h"
 #include "libc/str/str.h"
 #include "libc/sysv/consts/map.h"
 #include "libc/sysv/consts/o.h"
@@ -80,8 +80,9 @@ static bool IsMyDebugBinary(const char *path) {
     // contains the same number of bytes of code as our .com executable
     // which is currently running in memory.
     if ((size = lseek(fd, 0, SEEK_END)) != -1 &&
-        (dm = sys_mmap(0, size, PROT_READ, MAP_SHARED, fd, 0)).addr !=
-            MAP_FAILED) {
+        (dm = sys_mmap((void *)0x12345000000, size, PROT_READ, MAP_SHARED, fd,
+                       0))
+                .addr != MAP_FAILED) {
       if (READ32LE((char *)dm.addr) == READ32LE("\177ELF") &&
           ((Elf64_Ehdr *)dm.addr)->e_machine == GetElfMachine() &&
           GetElfSymbolValue(dm.addr, "_etext", &value)) {

test/posix/sa_resethand2_test.c

@@ -0,0 +1,74 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│ vi: set et 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/sigaction.h"
+#include "libc/calls/struct/sigset.h"
+#include "libc/dce.h"
+#include "libc/sysv/consts/sa.h"
+#include "libc/sysv/consts/sig.h"
+
+volatile int handler_invoked;
+
+void signal_handler(int signum) {
+  handler_invoked = 1;
+}
+
+int main() {
+  sigset_t mask, oldmask;
+  struct sigaction sa, current_sa;
+
+  if (IsWindows()) {
+    // TODO(jart): support non-fatal signals between processes
+    return 0;
+  }
+
+  sa.sa_handler = signal_handler;
+  sa.sa_flags = SA_RESETHAND;
+  sigemptyset(&sa.sa_mask);
+
+  if (sigaction(SIGINT, &sa, 0) == -1) {
+    return 1;
+  }
+
+  sigemptyset(&mask);
+  sigaddset(&mask, SIGINT);
+  if (sigprocmask(SIG_BLOCK, &mask, &oldmask) == -1) {
+    return 2;
+  }
+
+  int pid = fork();
+  if (pid == -1) {
+    return 3;
+  } else if (pid == 0) {
+    kill(getppid(), SIGINT);
+    return 0;
+  } else {
+    sigsuspend(&oldmask);
+    if (!handler_invoked) {
+      return 4;
+    }
+    if (sigaction(SIGINT, 0, &current_sa) == -1) {
+      return 5;
+    }
+    if (current_sa.sa_handler != SIG_DFL) {
+      return 6;
+    }
+    return 0;
+  }
+}

third_party/readline/signals.c

@@ -59,7 +59,6 @@ typedef struct sigaction sighandler_cxt;
 #  define rl_sigaction(s, nh, oh)	sigaction(s, nh, oh)
 #else
 typedef struct { SigHandler *sa_handler; int sa_mask, sa_flags; } sighandler_cxt;
-#  define sigemptyset(m)
 #endif /* !HAVE_POSIX_SIGNALS */
 
 #ifndef SA_RESTART