Make some quick fixes

libc/calls/getrandom.c

@@ -143,33 +143,27 @@ static void GetRandomArnd(char *p, size_t n) {
 }
 
 static ssize_t GetRandomBsd(char *p, size_t n, void impl(char *, size_t)) {
-  errno_t e;
   size_t m, i;
-  if (_weaken(pthread_testcancel_np) &&
-      (e = _weaken(pthread_testcancel_np)())) {
-    errno = e;
-    return -1;
-  }
   for (i = 0;;) {
     m = MIN(n - i, 256);
     impl(p + i, m);
     if ((i += m) == n) {
       return n;
     }
-    if (_weaken(pthread_testcancel)) {
-      _weaken(pthread_testcancel)();
-    }
   }
 }
 
 static ssize_t GetDevUrandom(char *p, size_t n) {
   int fd;
   ssize_t rc;
+  BLOCK_SIGNALS;
   fd = sys_openat(AT_FDCWD, "/dev/urandom", O_RDONLY | O_CLOEXEC, 0);
-  if (fd == -1) return -1;
+  if (fd != -1) {
-  pthread_cleanup_push((void *)sys_close, (void *)(intptr_t)fd);
+    rc = sys_read(fd, p, n);
-  rc = sys_read(fd, p, n);
+  } else {
-  pthread_cleanup_pop(1);
+    rc = -1;
+  }
+  ALLOW_SIGNALS;
   return rc;
 }
 
@@ -252,7 +246,7 @@ ssize_t getrandom(void *p, size_t n, unsigned f) {
   ssize_t rc;
   if ((!p && n) || (IsAsan() && !__asan_is_valid(p, n))) {
     rc = efault();
-  } else if ((f & ~(GRND_RANDOM | GRND_NONBLOCK))) {
+  } else if (f & ~(GRND_RANDOM | GRND_NONBLOCK)) {
     rc = einval();
   } else {
     rc = __getrandom(p, n, f);

libc/calls/read-nt.c

@@ -133,11 +133,12 @@ struct Keystrokes {
   struct Dll *line;
   struct Dll *free;
   bool end_of_file;
+  bool ohno_decckm;
   unsigned char pc;
   uint16_t utf16hs;
   pthread_mutex_t lock;
-  struct Keystroke pool[512];
   const struct VirtualKey *vkt;
+  struct Keystroke pool[512];
 };
 
 static struct Keystrokes __keystroke;
@@ -352,11 +353,11 @@ static textwindows int ProcessMouseEvent(const struct NtInputRecord *r,
         // we disable mouse highlighting when the tty is put in raw mode
         // to mouse wheel events with widely understood vt100 arrow keys
         *p++ = 033;
-        *p++ = '[';
+        *p++ = !__keystroke.ohno_decckm ? '[' : 'O';
         if (isup) {
-          *p++ = 'A';  // \e[A up
+          *p++ = 'A';
         } else {
-          *p++ = 'B';  // \e[B down
+          *p++ = 'B';
         }
       }
     }
@@ -637,6 +638,7 @@ textwindows void InterceptTerminalCommands(const char *data, size_t size) {
         } else if (data[i] == 'h') {
           if (x == 1) {
             __keystroke.vkt = kDecckm;  // \e[?1h decckm on
+            __keystroke.ohno_decckm = true;
           } else if ((ismouse |= IsMouseModeCommand(x))) {
             __ttyconf.magic |= kTtyXtMouse;
             cm2 |= kNtEnableMouseInput;
@@ -646,6 +648,7 @@ textwindows void InterceptTerminalCommands(const char *data, size_t size) {
         } else if (data[i] == 'l') {
           if (x == 1) {
             __keystroke.vkt = kVirtualKey;  // \e[?1l decckm off
+            __keystroke.ohno_decckm = false;
           } else if ((ismouse |= IsMouseModeCommand(x))) {
             __ttyconf.magic &= ~kTtyXtMouse;
             cm2 |= kNtEnableQuickEditMode;  // release mouse
@@ -709,6 +712,7 @@ static textwindows int WaitForConsole(struct Fd *f, sigset_t waitmask) {
   sigset_t m;
   int64_t sem;
   uint32_t ms = -1u;
+  struct PosixThread *pt;
   if (!__ttyconf.vmin) {
     if (!__ttyconf.vtime) {
       return 0;  // non-blocking w/o raising eagain
@@ -719,7 +723,7 @@ static textwindows int WaitForConsole(struct Fd *f, sigset_t waitmask) {
   if (f->flags & O_NONBLOCK) {
     return eagain();  // standard unix non-blocking
   }
-  struct PosixThread *pt = _pthread_self();
+  pt = _pthread_self();
   pt->pt_flags |= PT_RESTARTABLE;
   pt->pt_semaphore = sem = CreateSemaphore(0, 0, 1, 0);
   pthread_cleanup_push((void *)CloseHandle, (void *)sem);
@@ -733,8 +737,8 @@ static textwindows int WaitForConsole(struct Fd *f, sigset_t waitmask) {
   }
   __sig_finishwait(m);
   atomic_store_explicit(&pt->pt_blocker, PT_BLOCKER_CPU, memory_order_release);
-  pthread_cleanup_pop(true);
   pt->pt_flags &= ~PT_RESTARTABLE;
+  pthread_cleanup_pop(true);
   return rc;
 }
 

libc/intrin/ntcontext2linux.c

@@ -20,7 +20,6 @@
 #include "libc/log/libfatal.internal.h"
 #include "libc/nt/struct/context.h"
 #include "libc/str/str.h"
-
 #ifdef __x86_64__
 
 textwindows void _ntcontext2linux(ucontext_t *ctx, const struct NtContext *cr) {

libc/intrin/rand64.c

@@ -42,8 +42,6 @@ static struct {
  * @note this function takes 5 cycles (30 if `__threaded`)
  * @note this function is not intended for cryptography
  * @note this function passes bigcrush and practrand
- * @asyncsignalsafe
- * @vforksafe
  */
 uint64_t _rand64(void) {
   void *p;

libc/runtime/winmain.greg.c

@@ -136,7 +136,7 @@ static abi wontreturn void WinInit(const char16_t *cmdline) {
           m |= kNtEnableMouseInput | kNtEnableWindowInput |
                kNtEnableProcessedInput;
         } else {
-          m |= kNtEnableVirtualTerminalProcessing;
+          m |= kNtEnableProcessedOutput | kNtEnableVirtualTerminalProcessing;
         }
         __imp_SetConsoleMode(h, m);
       }

test/libc/calls/mkntcmdline_test.c

@@ -16,11 +16,13 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/assert.h"
 #include "libc/errno.h"
 #include "libc/mem/gc.internal.h"
 #include "libc/mem/mem.h"
 #include "libc/proc/ntspawn.h"
 #include "libc/str/str.h"
+#include "libc/testlib/ezbench.h"
 #include "libc/testlib/testlib.h"
 
 char16_t cmdline[32767];
@@ -103,3 +105,11 @@ TEST(mkntcmdline, testWut) {
   EXPECT_NE(-1, mkntcmdline(cmdline, argv));
   EXPECT_STREQ(u"C:\\Users\\jart\\𝑟𝑒𝑑𝑏𝑒𝑎𝑛.com --strace", cmdline);
 }
+
+BENCH(mkntcmdline, lotsOfArgs) {
+  static char *argv[1000];
+  for (int i = 0; i < 999; ++i) {
+    argv[i] = "hello there hello there";
+  }
+  EZBENCH2("mkntcmdline", donothing, unassert(!mkntcmdline(cmdline, argv)));
+}

test/libc/thread/stackoverflow1_test.c

@@ -1,106 +0,0 @@
-/*-*- 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/struct/rlimit.h"
-#include "libc/calls/struct/sigaction.h"
-#include "libc/calls/struct/sigaltstack.h"
-#include "libc/calls/struct/siginfo.h"
-#include "libc/dce.h"
-#include "libc/intrin/kprintf.h"
-#include "libc/limits.h"
-#include "libc/mem/gc.internal.h"
-#include "libc/mem/mem.h"
-#include "libc/runtime/runtime.h"
-#include "libc/runtime/sysconf.h"
-#include "libc/sysv/consts/rlimit.h"
-#include "libc/sysv/consts/sa.h"
-#include "libc/sysv/consts/sig.h"
-#include "libc/sysv/consts/ss.h"
-#include "libc/testlib/testlib.h"
-#include "libc/thread/thread.h"
-
-/**
- * stack overflow recovery technique #1
- * overflow the gigantic main process stack
- * simple but it can upset kernels / libraries
- */
-
-jmp_buf recover;
-volatile bool smashed_stack;
-
-void CrashHandler(int sig, siginfo_t *si, void *ctx) {
-  struct sigaltstack ss;
-  ASSERT_SYS(0, 0, sigaltstack(0, &ss));
-  ASSERT_EQ(SS_ONSTACK, ss.ss_flags);
-  kprintf("kprintf avoids overflowing %G %p\n", si->si_signo, si->si_addr);
-  smashed_stack = true;
-  ASSERT_TRUE(__is_stack_overflow(si, ctx));
-  longjmp(recover, 123);
-}
-
-void SetUp(void) {
-
-  // tune down the main process's stack size to a reasonable amount
-  // some operating systems, e.g. freebsd, will do things like have
-  // 500mb RLIMIT_STACK by default, even on machines with 400mb RAM
-  struct rlimit rl = {2 * 1024 * 1024, 2 * 1024 * 1024};
-  if (!IsWindows()) setrlimit(RLIMIT_STACK, &rl);
-
-  // set up the signal handler and alternative stack
-  struct sigaction sa;
-  struct sigaltstack ss;
-  ss.ss_flags = 0;
-  ss.ss_size = sysconf(_SC_MINSIGSTKSZ) + 8192;
-  ss.ss_sp = _mapanon(ss.ss_size);
-  ASSERT_SYS(0, 0, sigaltstack(&ss, 0));
-  sa.sa_flags = SA_SIGINFO | SA_ONSTACK;  // <-- important
-  sigemptyset(&sa.sa_mask);
-  sa.sa_sigaction = CrashHandler;
-  sigaction(SIGBUS, &sa, 0);
-  sigaction(SIGSEGV, &sa, 0);
-}
-
-int StackOverflow(int f(), int n) {
-  if (n < INT_MAX) {
-    return f(f, n + 1) - 1;
-  } else {
-    return INT_MAX;
-  }
-}
-
-int (*pStackOverflow)(int (*)(), int) = StackOverflow;
-
-TEST(stackoverflow, standardStack_altStack_process_longjmp) {
-  if (IsTiny()) return;  // TODO(jart): why?
-
-  int jumpcode;
-  if (!(jumpcode = setjmp(recover))) {
-    exit(pStackOverflow(pStackOverflow, 0));
-  }
-  ASSERT_EQ(123, jumpcode);
-  ASSERT_TRUE(smashed_stack);
-
-  // here's where longjmp() gets us into trouble
-  struct sigaltstack ss;
-  ASSERT_SYS(0, 0, sigaltstack(0, &ss));
-  if (IsXnu() || IsNetbsd()) {
-    ASSERT_EQ(SS_ONSTACK, ss.ss_flags);  // wut
-  } else {
-    ASSERT_EQ(0, ss.ss_flags);
-  }
-}

test/libc/thread/stackoverflow2_test.c

@@ -1,105 +0,0 @@
-/*-*- 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/struct/sigaction.h"
-#include "libc/calls/struct/sigaltstack.h"
-#include "libc/calls/struct/siginfo.h"
-#include "libc/dce.h"
-#include "libc/intrin/kprintf.h"
-#include "libc/limits.h"
-#include "libc/mem/gc.internal.h"
-#include "libc/mem/mem.h"
-#include "libc/runtime/runtime.h"
-#include "libc/runtime/sysconf.h"
-#include "libc/sysv/consts/sa.h"
-#include "libc/sysv/consts/sig.h"
-#include "libc/sysv/consts/ss.h"
-#include "libc/testlib/testlib.h"
-#include "libc/thread/thread.h"
-
-/**
- * stack overflow recovery technique #2
- * longjmp out of signal back into thread
- * simple but it can upset kernels / libraries
- */
-
-jmp_buf recover;
-volatile bool smashed_stack;
-
-void CrashHandler(int sig, siginfo_t *si, void *ctx) {
-  struct sigaltstack ss;
-  ASSERT_SYS(0, 0, sigaltstack(0, &ss));
-  ASSERT_EQ(SS_ONSTACK, ss.ss_flags);
-  kprintf("kprintf avoids overflowing %G %p\n", si->si_signo, si->si_addr);
-  smashed_stack = true;
-  ASSERT_TRUE(__is_stack_overflow(si, ctx));
-  longjmp(recover, 123);
-}
-
-int StackOverflow(int f(), int n) {
-  if (n < INT_MAX) {
-    return f(f, n + 1) - 1;
-  } else {
-    return INT_MAX;
-  }
-}
-
-int (*pStackOverflow)(int (*)(), int) = StackOverflow;
-
-void *MyPosixThread(void *arg) {
-  int jumpcode;
-  struct sigaction sa, o1, o2;
-  struct sigaltstack ss;
-  ss.ss_flags = 0;
-  ss.ss_size = sysconf(_SC_MINSIGSTKSZ) + 4096;
-  ss.ss_sp = gc(malloc(ss.ss_size));
-  ASSERT_SYS(0, 0, sigaltstack(&ss, 0));
-  sa.sa_flags = SA_SIGINFO | SA_ONSTACK;  // <-- important
-  sigemptyset(&sa.sa_mask);
-  sa.sa_sigaction = CrashHandler;
-  sigaction(SIGBUS, &sa, &o1);
-  sigaction(SIGSEGV, &sa, &o2);
-  if (!(jumpcode = setjmp(recover))) {
-    exit(pStackOverflow(pStackOverflow, 0));
-  }
-  ASSERT_EQ(123, jumpcode);
-  sigaction(SIGSEGV, &o2, 0);
-  sigaction(SIGBUS, &o1, 0);
-  // here's where longjmp() gets us into trouble
-  ASSERT_SYS(0, 0, sigaltstack(0, &ss));
-  if (IsXnu() || IsNetbsd()) {
-    ASSERT_EQ(SS_ONSTACK, ss.ss_flags);  // wut
-  } else {
-    ASSERT_EQ(0, ss.ss_flags);
-  }
-  return 0;
-}
-
-TEST(stackoverflow, standardStack_altStack_thread_longjmp) {
-  pthread_t th;
-  struct sigaltstack ss;
-  for (int i = 0; i < 2; ++i) {
-    smashed_stack = false;
-    pthread_create(&th, 0, MyPosixThread, 0);
-    pthread_join(th, 0);
-    ASSERT_TRUE(smashed_stack);
-    // this should be SS_DISABLE but ShowCrashReports() creates an alt stack
-    ASSERT_SYS(0, 0, sigaltstack(0, &ss));
-    ASSERT_EQ(0, ss.ss_flags);
-  }
-}

test/libc/thread/stackoverflow3_test.c

@@ -1,116 +0,0 @@
-/*-*- 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/struct/sigaction.h"
-#include "libc/calls/struct/sigaltstack.h"
-#include "libc/calls/struct/siginfo.h"
-#include "libc/calls/struct/ucontext.internal.h"
-#include "libc/calls/ucontext.h"
-#include "libc/intrin/kprintf.h"
-#include "libc/limits.h"
-#include "libc/mem/gc.internal.h"
-#include "libc/mem/mem.h"
-#include "libc/runtime/runtime.h"
-#include "libc/runtime/sysconf.h"
-#include "libc/sysv/consts/sa.h"
-#include "libc/sysv/consts/sig.h"
-#include "libc/sysv/consts/ss.h"
-#include "libc/testlib/testlib.h"
-#include "libc/thread/thread.h"
-
-/**
- * stack overflow recovery technique #3
- * rewrite thread cpu state to call pthread_exit
- * this method returns gracefully from signal handlers
- * unfortunately it relies on cpu architecture knowledge
- */
-
-volatile bool smashed_stack;
-
-void Exiter(void *rc) {
-  struct sigaltstack ss;
-  ASSERT_SYS(0, 0, sigaltstack(0, &ss));
-  ASSERT_EQ(0, ss.ss_flags);
-  pthread_exit(rc);
-}
-
-void CrashHandler(int sig, siginfo_t *si, void *arg) {
-  ucontext_t *ctx = arg;
-  struct sigaltstack ss;
-  ASSERT_SYS(0, 0, sigaltstack(0, &ss));
-  ASSERT_EQ(SS_ONSTACK, ss.ss_flags);
-  kprintf("kprintf avoids overflowing %G %p\n", si->si_signo, si->si_addr);
-  smashed_stack = true;
-  ASSERT_TRUE(__is_stack_overflow(si, ctx));
-  //
-  // the backtrace will look like this
-  //
-  //   0x000000000042561d: pthread_exit at pthread_exit.c:99
-  //   0x0000000000418777: Exiter at stackoverflow2_test.c:40
-  //   0x00000000004186d8: CrashHandler at stackoverflow2_test.c:49
-  //   0x000000000041872a: StackOverflow at stackoverflow2_test.c:53
-  //   0x000000000041872a: StackOverflow at stackoverflow2_test.c:53
-  //   0x000000000041872a: StackOverflow at stackoverflow2_test.c:53
-  //   ...
-  //
-  ctx->uc_mcontext.ARG0 = 123;
-  ctx->uc_mcontext.PC = (long)Exiter;
-  ctx->uc_mcontext.SP += 32768;
-  ctx->uc_mcontext.SP &= -16;
-  ctx->uc_mcontext.SP -= 8;
-}
-
-int StackOverflow(int f(), int n) {
-  if (n < INT_MAX) {
-    return f(f, n + 1) - 1;
-  } else {
-    return INT_MAX;
-  }
-}
-
-int (*pStackOverflow)(int (*)(), int) = StackOverflow;
-
-void *MyPosixThread(void *arg) {
-  struct sigaction sa;
-  struct sigaltstack ss;
-  ss.ss_flags = 0;
-  ss.ss_size = sysconf(_SC_MINSIGSTKSZ) + 4096;
-  ss.ss_sp = gc(malloc(ss.ss_size));
-  ASSERT_SYS(0, 0, sigaltstack(&ss, 0));
-  sa.sa_flags = SA_SIGINFO | SA_ONSTACK;  // <-- important
-  sigemptyset(&sa.sa_mask);
-  sa.sa_sigaction = CrashHandler;
-  sigaction(SIGBUS, &sa, 0);
-  sigaction(SIGSEGV, &sa, 0);
-  exit(pStackOverflow(pStackOverflow, 0));
-  return 0;
-}
-
-TEST(stackoverflow, standardStack_altStack_thread_teleport) {
-  void *res;
-  pthread_t th;
-  struct sigaltstack ss;
-  smashed_stack = false;
-  pthread_create(&th, 0, MyPosixThread, 0);
-  pthread_join(th, &res);
-  ASSERT_EQ((void *)123L, res);
-  ASSERT_TRUE(smashed_stack);
-  // this should be SS_DISABLE but ShowCrashReports() creates an alt stack
-  ASSERT_SYS(0, 0, sigaltstack(0, &ss));
-  ASSERT_EQ(0, ss.ss_flags);
-}

tool/viz/fixconsole.c

@@ -16,20 +16,33 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/calls.h"
 #include "libc/dce.h"
-#include "libc/intrin/kprintf.h"
+#include "libc/intrin/describeflags.internal.h"
 #include "libc/nt/console.h"
 #include "libc/nt/enum/consolemodeflags.h"
 #include "libc/nt/runtime.h"
-#include "libc/runtime/runtime.h"
-#include "libc/stdio/stdio.h"
 #if defined(__x86_64__) && SupportsWindows()
 
 int main(int argc, char *argv[]) {
+
   if (!IsWindows()) {
-    kprintf("%s is intended for windows%n", argv[0]);
+    tinyprint(2, argv[0], " is intended for windows\n", NULL);
     return 1;
   }
+
+  // clear console and print old config
+  uint32_t cm;
+  tinyprint(1, "\e[H\e[J", NULL);
+  tinyprint(1, "broken console settings were\r\n", NULL);
+  GetConsoleMode(GetStdHandle(kNtStdInputHandle), &cm);
+  tinyprint(1, "stdin: ", DescribeNtConsoleInFlags(cm), "\r\n", NULL);
+  GetConsoleMode(GetStdHandle(kNtStdOutputHandle), &cm);
+  tinyprint(1, "stdout: ", DescribeNtConsoleOutFlags(cm), "\r\n", NULL);
+  GetConsoleMode(GetStdHandle(kNtStdErrorHandle), &cm);
+  tinyprint(1, "stderr: ", DescribeNtConsoleOutFlags(cm), "\r\n", NULL);
+
+  // fix console settings
   SetConsoleMode(GetStdHandle(kNtStdInputHandle),
                  kNtEnableProcessedInput | kNtEnableLineInput |
                      kNtEnableEchoInput | kNtEnableMouseInput |
@@ -40,13 +53,14 @@ int main(int argc, char *argv[]) {
   SetConsoleMode(GetStdHandle(kNtStdErrorHandle),
                  kNtEnableProcessedOutput | kNtEnableWrapAtEolOutput |
                      kNtEnableVirtualTerminalProcessing);
-  _Exit(0);
+
+  return 0;
 }
 
 #else
 int main(int argc, char *argv[]) {
-  fprintf(stderr,
+  tinyprint(2, "fixconsole not supported on this cpu arch or build config\n",
-          "fixconsole not supported on this cpu arch or build config\n");
+            NULL);
   return 1;
 }
 #endif /* __x86_64__ && SupportsWindows() */