Make improvements

- Fix build flakes - Polyfill SIGWINCH on Windows - Fix an execve issue on Windows - Make strerror show more information - Improve cmd.exe setup/teardown on Windows - Support bracketed paste mode in Blinkenlights - Show keyboard shortcuts in Blinkenlights status bar - Fixed copy_file_range() and copyfile() w/ zip filesystem - Size optimize GetDosArgv() to keep life.com 12kb in size - Improve Blinkenlights ability to load weird ELF executables - Fix program_executable_name and add GetInterpreterExecutableName - Make Python in tiny mode fail better if docstrings are requested - Update Python test exclusions in tiny* modes such as tinylinux - Add bulletproof unbreakable kprintf() troubleshooting function - Remove "oldskool" keyword from ape.S for virus scanners - Fix issue that caused backtraces to not print sometimes - Improve Blinkenlights serial uart character i/o - Make clock_gettime() not clobber errno on xnu - Improve sha256 cpuid check for old computers - Integrate some bestline linenoise fixes - Show runit process names better in htop - Remove SIGPIPE from ShowCrashReports() - Make realpath() not clobber errno - Avoid attaching GDB on non-Linux - Improve img.com example
2025-07-25 03:50:29 +00:00 · 2022-03-16 13:33:13 -07:00 · 2022-03-16 13:33:13 -07:00 · b45d50b690
commit b45d50b690
parent 2a938b3eaa
194 changed files with 4881 additions and 2966 deletions
--- a/tool/build/blinkenlights.c
+++ b/tool/build/blinkenlights.c
@ -30,6 +30,7 @@
 #include "libc/calls/struct/termios.h"
 #include "libc/calls/struct/winsize.h"
 #include "libc/calls/termios.h"
+#include "libc/dce.h"
 #include "libc/fmt/bing.internal.h"
 #include "libc/fmt/conv.h"
 #include "libc/fmt/fmt.h"
@ -37,15 +38,18 @@
 #include "libc/intrin/asan.internal.h"
 #include "libc/intrin/pcmpeqb.h"
 #include "libc/intrin/pmovmskb.h"
+#include "libc/limits.h"
 #include "libc/log/check.h"
 #include "libc/log/color.internal.h"
 #include "libc/log/log.h"
 #include "libc/macros.internal.h"
 #include "libc/math.h"
 #include "libc/mem/mem.h"
+#include "libc/rand/rand.h"
 #include "libc/runtime/gc.internal.h"
 #include "libc/runtime/runtime.h"
 #include "libc/sock/sock.h"
+#include "libc/stdio/append.internal.h"
 #include "libc/stdio/stdio.h"
 #include "libc/str/str.h"
 #include "libc/str/thompike.h"
@ -198,6 +202,12 @@ struct MemoryView {
  int zoom;
 };

+struct Keystrokes {
+  unsigned i;
+  char p[4][32];
+  long double s[4];
+};
+
 struct MachineState {
  uint64_t ip;
  uint8_t cs[8];
@ -296,6 +306,7 @@ static struct Pty *pty;
 static struct Machine *m;

 static struct Panels pan;
+static struct Keystrokes keystrokes;
 static struct Breakpoints breakpoints;
 static struct MemoryView codeview;
 static struct MemoryView readview;
@ -545,6 +556,10 @@ static void ShowCursor(void) {
  TtyWriteString("\e[?25h");
 }

+static void EnableSafePaste(void) {
+  TtyWriteString("\e[?2004h");
+}
+
 static void DisableSafePaste(void) {
  TtyWriteString("\e[?2004l");
 }
@ -596,7 +611,7 @@ static void TuiRejuvinate(void) {
  CHECK_NE(-1, ioctl(ttyout, TCSETS, &term));
  xsigaction(SIGBUS, OnSigBusted, SA_NODEFER, 0, NULL);
  EnableMouseTracking();
-  DisableSafePaste();
+  EnableSafePaste();
 }

 static void OnQ(void) {
@ -639,12 +654,14 @@ static void TtyRestore2(void) {
  DEBUGF("TtyRestore2");
  ioctl(ttyout, TCSETS, &oldterm);
  DisableMouseTracking();
+  DisableSafePaste();
 }

 static void TuiCleanup(void) {
  sigaction(SIGCONT, oldsig + 2, NULL);
  TtyRestore1();
  DisableMouseTracking();
+  DisableSafePaste();
  tuimode = false;
  LeaveScreen();
 }
@ -682,12 +699,14 @@ static void LoadSyms(void) {
 static int DrainInput(int fd) {
  char buf[32];
  struct pollfd fds[1];
-  for (;;) {
-    fds[0].fd = fd;
-    fds[0].events = POLLIN;
-    if (poll(fds, ARRAYLEN(fds), 0) == -1) return -1;
-    if (!(fds[0].revents & POLLIN)) break;
-    if (read(fd, buf, sizeof(buf)) == -1) return -1;
+  if (!IsWindows()) {
+    for (;;) {
+      fds[0].fd = fd;
+      fds[0].events = POLLIN;
+      if (poll(fds, ARRAYLEN(fds), 0) == -1) return -1;
+      if (!(fds[0].revents & POLLIN)) break;
+      if (read(fd, buf, sizeof(buf)) == -1) return -1;
+    }
  }
  return 0;
 }
@ -1602,6 +1621,34 @@ static int AppendStat(struct Buffer *b, const char *name, int64_t value,
  return 1 + width;
 }

+static char *GetStatus(int m) {
+  bool first;
+  char *b = 0;
+  unsigned i, n;
+  long double t;
+  if (statusmessage && nowl() < statusexpires) {
+    appends(&b, statusmessage);
+  } else {
+    appends(&b, "das blinkenlights");
+  }
+  n = ARRAYLEN(keystrokes.p);
+  for (first = true, t = nowl(), i = 1; i <= n; --i) {
+    if (!keystrokes.p[(keystrokes.i - i) % n][0]) continue;
+    if (t - keystrokes.s[(keystrokes.i - i) % n] > 1) continue;
+    if (first) {
+      first = false;
+      appends(&b, " (keystroke: ");
+    } else {
+      appendw(&b, ' ');
+    }
+    appends(&b, keystrokes.p[(keystrokes.i - i) % n]);
+  }
+  if (!first) {
+    appendw(&b, ')');
+  }
+  return b;
+}
+
 static void DrawStatus(struct Panel *p) {
  int yn, xn, rw;
  struct Buffer *s;
@ -1621,9 +1668,7 @@ static void DrawStatus(struct Panel *p) {
  rw += AppendStat(s, "freed", a->freed, a->freed != b->freed);
  rw += AppendStat(s, "tables", a->pagetables, a->pagetables != b->pagetables);
  rw += AppendStat(s, "fds", m->fds.i, false);
-  AppendFmt(&p->lines[0], "\e[7m%-*s%s\e[0m", xn - rw,
-            statusmessage && nowl() < statusexpires ? statusmessage
-                                                    : "das blinkenlights",
+  AppendFmt(&p->lines[0], "\e[7m%-*s%s\e[0m", xn - rw, gc(GetStatus(xn - rw)),
            s->p);
  free(s->p);
  free(s);
@ -1700,6 +1745,29 @@ static void ReactiveDraw(void) {
  }
 }

+static void DescribeKeystroke(char *b, const char *p) {
+  int c;
+  do {
+    c = *p++ & 255;
+    if (c == '\e') {
+      b = stpcpy(b, "ALT-");
+      c = *p++ & 255;
+    }
+    if (c <= 32) {
+      b = stpcpy(b, "CTRL-");
+      c = CTRL(c);
+    }
+    *b++ = c;
+    *b = 0;
+  } while (*p);
+}
+
+static void RecordKeystroke(const char *k) {
+  keystrokes.s[keystrokes.i] = nowl();
+  DescribeKeystroke(keystrokes.p[keystrokes.i], k);
+  keystrokes.i = (keystrokes.i + 1) % ARRAYLEN(keystrokes.p);
+}
+
 static void HandleAlarm(void) {
  alarmed = false;
  action &= ~ALARM;
@ -1719,6 +1787,8 @@ static void HandleAppReadInterrupt(void) {
  }
  if (action & INT) {
    action &= ~INT;
+    RecordKeystroke("\3");
+    ReactiveDraw();
    if (action & CONTINUE) {
      action &= ~CONTINUE;
    } else {
@ -1770,33 +1840,47 @@ static struct Mouse ParseMouse(char *p) {
  return m;
 }

-static ssize_t ReadPtyFdDirect(int fd, void *data, size_t size) {
+static ssize_t ReadAnsi(int fd, char *p, size_t n) {
  ssize_t rc;
-  char buf[32];
  struct Mouse m;
-  DEBUGF("ReadPtyFdDirect");
-  pty->conf |= kPtyBlinkcursor;
  for (;;) {
    ReactiveDraw();
-    if ((rc = readansi(fd, buf, sizeof(buf))) != -1) {
-      if (tuimode && rc > 3 &&
-          (buf[0] == '\e' && buf[1] == '[' && buf[2] == '<')) {
-        m = ParseMouse(buf + 3);
-        if (LocatePanel(m.y, m.x) != &pan.display) {
-          HandleKeyboard(buf);
+    if ((rc = readansi(fd, p, n)) != -1) {
+      if (tuimode && rc > 3 && p[0] == '\e' && p[1] == '[') {
+        if (p[2] == '2' && p[3] == '0' && p[4] == '0' && p[5] == '~') {
+          belay = true;
          continue;
        }
+        if (p[2] == '2' && p[3] == '0' && p[4] == '1' && p[5] == '~') {
+          belay = false;
+          continue;
+        }
+        if (p[2] == '<') {
+          m = ParseMouse(p + 3);
+          if (LocatePanel(m.y, m.x) != &pan.display) {
+            HandleKeyboard(p);
+            continue;
+          }
+        }
      }
-      break;
+      return rc;
+    } else {
+      CHECK_EQ(EINTR, errno);
+      HandleAppReadInterrupt();
    }
-    CHECK_EQ(EINTR, errno);
-    HandleAppReadInterrupt();
  }
+}
+
+static ssize_t ReadPtyFdDirect(int fd) {
+  ssize_t rc;
+  char buf[32];
+  pty->conf |= kPtyBlinkcursor;
+  rc = ReadAnsi(fd, buf, sizeof(buf));
  pty->conf &= ~kPtyBlinkcursor;
  if (rc > 0) {
    PtyWriteInput(pty, buf, rc);
    ReactiveDraw();
-    rc = PtyRead(pty, data, size);
+    rc = 0;
  }
  return rc;
 }
@ -1814,15 +1898,62 @@ static ssize_t OnPtyFdReadv(int fd, const struct iovec *iov, int iovlen) {
    }
  }
  if (size) {
-    if (!(rc = PtyRead(pty, data, size))) {
-      rc = ReadPtyFdDirect(fd, data, size);
+    for (;;) {
+      if ((rc = PtyRead(pty, data, size))) {
+        return rc;
+      }
+      if (ReadPtyFdDirect(fd) == -1) {
+        return -1;
+      }
    }
-    return rc;
  } else {
    return 0;
  }
 }

+static int OnPtyFdPoll(struct pollfd *fds, size_t nfds, int ms) {
+  bool once, rem;
+  int i, t, re, rc;
+  struct pollfd p2;
+  ms &= INT_MAX;
+  for (once = t = i = 0; i < nfds; ++i) {
+    re = 0;
+    if (fds[i].fd >= 0) {
+      if (pty->input.i) {
+        re = POLLIN | POLLOUT;
+        ++t;
+      } else {
+        if (!once) {
+          ReactiveDraw();
+          once = true;
+        }
+        if (!IsWindows()) {
+          p2.fd = fds[i].fd;
+          p2.events = fds[i].events;
+          switch (poll(&p2, 1, ms)) {
+            case -1:
+              re = POLLERR;
+              ++t;
+              break;
+            case 0:
+              break;
+            case 1:
+              re = p2.revents;
+              ++t;
+              break;
+            default:
+              unreachable;
+          }
+        } else {
+          re = POLLIN | POLLOUT; /* xxx */
+        }
+      }
+    }
+    fds[i].revents = re;
+  }
+  return t;
+}
+
 static void DrawDisplayOnly(struct Panel *p) {
  struct Buffer b;
  int i, y, yn, xn, tly, tlx, conf;
@ -1910,6 +2041,7 @@ static const struct MachineFdCb kMachineFdCbPty = {
    .readv = OnPtyFdReadv,
    .writev = OnPtyFdWritev,
    .ioctl = OnPtyFdIoctl,
+    .poll = OnPtyFdPoll,
 };

 static void LaunchDebuggerReactively(void) {
@ -2137,11 +2269,10 @@ static void OnVidyaServiceTeletypeOutput(void) {
  int n;
  uint64_t w;
  char buf[12];
-  n = FormatCga(m->bx[0], buf);
+  n = 0 /* FormatCga(m->bx[0], buf) */;
  w = tpenc(VidyaServiceXlatTeletype(m->ax[0]));
-  do {
-    buf[n++] = w;
-  } while ((w >>= 8));
+  do buf[n++] = w;
+  while ((w >>= 8));
  PtyWrite(pty, buf, n);
 }

@ -2173,64 +2304,19 @@ static void OnVidyaService(void) {
 static void OnKeyboardServiceReadKeyPress(void) {
  wint_t x;
  uint8_t b;
-  ssize_t rc;
  size_t i, n;
  struct Mouse mo;
  static char buf[32];
  static size_t pending;
-  static const char *fun;
-  static const char *prog /* = "(CONS (QUOTE A) (QUOTE B))" */;
  pty->conf |= kPtyBlinkcursor;
-  if (!fun && prog) {
-    fun = prog;
-    belay = 1;
-  }
-  if (fun && *fun) {
-    b = *fun++;
-    if (!*fun) {
-      ReactiveDraw();
-      belay = 0;
-    }
-  } else {
-    if (!pending) {
-      for (;;) {
-        ReactiveDraw();
-        if ((rc = readansi(0, buf, sizeof(buf))) != -1) {
-          if (!rc) {
-            exitcode = 0;
-            action |= EXIT;
-            return;
-          }
-          if (!memcmp(buf, "\e[200~", 6) || !memcmp(buf, "\e[201~", 6)) {
-            continue;
-          }
-          if ((x = buf[0] & 0377) >= 0300) {
-            n = ThomPikeLen(x);
-            x = ThomPikeByte(x);
-            for (i = 1; i < n; ++i) {
-              x = ThomPikeMerge(x, buf[i] & 0377);
-            }
-            buf[0] = unbing(x);
-            rc = 1;
-          } else if (tuimode && rc > 3 &&
-                     (buf[0] == '\e' && buf[1] == '[' && buf[2] == '<')) {
-            mo = ParseMouse(buf + 3);
-            if (LocatePanel(mo.y, mo.x) != &pan.display) {
-              HandleKeyboard(buf);
-              continue;
-            }
-          }
-          pending = rc;
-          break;
-        }
-        CHECK_EQ(EINTR, errno);
-        HandleAppReadInterrupt();
-      }
-    }
-    b = buf[0];
-    memmove(buf, buf + 1, pending - 1);
-    --pending;
+  if (!pending && !(pending = ReadAnsi(0, buf, sizeof(buf)))) {
+    exitcode = 0;
+    action |= EXIT;
+    return;
  }
+  b = buf[0];
+  memmove(buf, buf + 1, pending - 1);
+  --pending;
  pty->conf &= ~kPtyBlinkcursor;
  ReactiveDraw();
  if (b == 0x7F) b = '\b';
@ -2521,7 +2607,11 @@ static bool HasPendingKeyboard(void) {
 }

 static void Sleep(int ms) {
-  poll((struct pollfd[]){{ttyin, POLLIN}}, 1, ms);
+  if (IsWindows()) {
+    usleep(ms * 1000L);
+  } else {
+    poll((struct pollfd[]){{ttyin, POLLIN}}, 1, ms);
+  }
 }

 static void OnMouseWheelUp(struct Panel *p, int y, int x) {
@ -2596,7 +2686,8 @@ static void OnHelp(void) {
  dialog = HELP;
 }

-static void HandleKeyboard(const char *p) {
+static void HandleKeyboard(const char *k) {
+  const char *p = k;
  switch (*p++) {
    CASE('q', OnQ());
    CASE('v', OnV());
@ -2634,9 +2725,9 @@ static void HandleKeyboard(const char *p) {
          switch (*p++) {
            CASE('P', OnHelp()); /* \eOP is F1 */
            default:
-              break;
+              return;
          }
-          break;
+          return;
        case '[':
          switch (*p++) {
            CASE('<', OnMouse(p));
@ -2649,16 +2740,17 @@ static void HandleKeyboard(const char *p) {
            CASE('5', OnPageUp());    /* \e[1~ is pgup */
            CASE('6', OnPageDown());  /* \e[1~ is pgdn */
            default:
-              break;
+              return;
          }
-          break;
+          return;
        default:
-          break;
+          return;
      }
      break;
    default:
-      break;
+      return;
  }
+  RecordKeystroke(k);
 }

 static void ReadKeyboard(void) {
@ -2824,6 +2916,8 @@ static void Tui(void) {
      if (action & INT) {
        INFOF("TUI INT");
        action &= ~INT;
+        RecordKeystroke("\3");
+        ReactiveDraw();
        if (action & (CONTINUE | NEXT | FINISH)) {
          action &= ~(CONTINUE | NEXT | FINISH);
        } else {
@ -3012,11 +3106,12 @@ static void OnlyRunOnFirstCpu(void) {
 int main(int argc, char *argv[]) {
  if (!NoDebug()) showcrashreports();
  pty = NewPty();
+  pty->conf |= kPtyNocanon;
  m = NewMachine();
  m->mode = XED_MACHINE_MODE_LONG_64;
  m->onbinbase = OnBinbase;
  m->onlongbranch = OnLongBranch;
-  speed = 16;
+  speed = 32;
  SetXmmSize(2);
  SetXmmDisp(kXmmHex);
  if ((colorize = cancolor())) {
--- a/tool/build/compile.c
+++ b/tool/build/compile.c
@ -28,9 +28,11 @@
 #include "libc/calls/struct/sigset.h"
 #include "libc/calls/struct/stat.h"
 #include "libc/calls/struct/timeval.h"
+#include "libc/dce.h"
 #include "libc/errno.h"
 #include "libc/fmt/conv.h"
 #include "libc/fmt/itoa.h"
+#include "libc/intrin/kprintf.h"
 #include "libc/limits.h"
 #include "libc/log/color.internal.h"
 #include "libc/log/log.h"
@ -43,6 +45,7 @@
 #include "libc/stdio/append.internal.h"
 #include "libc/stdio/stdio.h"
 #include "libc/str/str.h"
+#include "libc/sysv/consts/auxv.h"
 #include "libc/sysv/consts/clock.h"
 #include "libc/sysv/consts/itimer.h"
 #include "libc/sysv/consts/o.h"
@ -95,8 +98,8 @@ FLAGS\n\
  -T TARGET    specifies target name for V=0 logging\n\
  -A ACTION    specifies short command name for V=0 logging\n\
  -V NUMBER    specifies compiler version\n\
-  -C SECS      set cpu limit [default 8]\n\
-  -L SECS      set lat limit [default 64]\n\
+  -C SECS      set cpu limit [default 16]\n\
+  -L SECS      set lat limit [default 90]\n\
  -M BYTES     set mem limit [default 512m]\n\
  -F BYTES     set fsz limit [default 100m]\n\
  -O BYTES     set out limit [default 1m]\n\
@ -194,6 +197,7 @@ const char *const kSafeEnv[] = {
    "MODE",       // needed by test scripts
    "PATH",       // needed by clang
    "PWD",        // just seems plain needed
+    "STRACE",     // useful for troubleshooting
    "TERM",       // needed by IsTerminalInarticulate
    "TMPDIR",     // needed by compiler
 };
@ -223,6 +227,7 @@ const char *const kGccOnlyFlags[] = {
    "-fno-gnu-unique",
    "-fno-gnu-unique",
    "-fno-instrument-functions",
+    "-fno-schedule-insns2",
    "-fno-whole-program",
    "-fopt-info-vec",
    "-fopt-info-vec-missed",
@ -324,10 +329,14 @@ int GetTerminalWidth(void) {
  }
 }

-int GetLineWidth(void) {
+int GetLineWidth(bool *isineditor) {
  char *s;
  struct winsize ws = {0};
-  if ((s = getenv("COLUMNS"))) {
+  s = getenv("COLUMNS");
+  if (isineditor) {
+    *isineditor = !!s;
+  }
+  if (s) {
    return atoi(s);
  } else if (ioctl(2, TIOCGWINSZ, &ws) != -1) {
    if (ws.ws_col && ws.ws_row) {
@ -398,11 +407,20 @@ bool FileExistsAndIsNewerThan(const char *filepath, const char *thanpath) {
  return st1.st_mtim.tv_nsec >= st2.st_mtim.tv_nsec;
 }

+static size_t TallyArgs(char **p) {
+  size_t n;
+  for (n = 0; *p; ++p) {
+    n += sizeof(*p);
+    n += strlen(*p) + 1;
+  }
+  return n;
+}
+
 void AddStr(struct Strings *l, char *s) {
  l->p = realloc(l->p, (++l->n + 1) * sizeof(*l->p));
  l->p[l->n - 1] = s;
  l->p[l->n - 0] = 0;
-};
+}

 void AddEnv(char *s) {
  AddStr(&env, s);
@ -433,7 +451,15 @@ void AddArg(char *s) {
    } else {
      appends(&shortened, s);
    }
-  } else if (s[0] == '-' && (!s[1] || s[1] == 'o' || (s[1] == '-' && !s[2]) ||
+  } else if (/*
+              * a in ('-', '--') or
+              * a.startswith('-o') or
+              * c == 'ld' and a == '-T' or
+              * c == 'cc' and a.startswith('-O') or
+              * c == 'cc' and a.startswith('-x') or
+              * c == 'cc' and a in ('-c', '-E', '-S')
+              */
+             s[0] == '-' && (!s[1] || s[1] == 'o' || (s[1] == '-' && !s[2]) ||
                             (isbfd && (s[1] == 'T' && !s[2])) ||
                             (iscc && (s[1] == 'O' || s[1] == 'x' ||
                                       (!s[2] && (s[1] == 'c' || s[1] == 'E' ||
@ -486,6 +512,56 @@ void SetMemLimit(long n) {
  setrlimit(RLIMIT_AS, &rlim);
 }

+bool ArgNeedsShellQuotes(const char *s) {
+  if (*s) {
+    for (;;) {
+      switch (*s++ & 255) {
+        case 0:
+          return false;
+        case '-':
+        case '.':
+        case '/':
+        case '_':
+        case '=':
+        case ':':
+        case '0' ... '9':
+        case 'A' ... 'Z':
+        case 'a' ... 'z':
+          break;
+        default:
+          return true;
+      }
+    }
+  } else {
+    return true;
+  }
+}
+
+char *AddShellQuotes(const char *s) {
+  char *p, *q;
+  size_t i, j, n;
+  n = strlen(s);
+  p = malloc(1 + n * 5 + 1 + 1);
+  j = 0;
+  p[j++] = '\'';
+  for (i = 0; i < n; ++i) {
+    if (s[i] != '\'') {
+      p[j++] = s[i];
+    } else {
+      p[j + 0] = '\'';
+      p[j + 1] = '"';
+      p[j + 2] = '\'';
+      p[j + 3] = '"';
+      p[j + 4] = '\'';
+      j += 5;
+    }
+  }
+  p[j++] = '\'';
+  p[j] = 0;
+  if ((q = realloc(p, j + 1))) p = q;
+  return p;
+}
+
 int Launch(void) {
  size_t got;
  ssize_t rc;
@ -499,7 +575,19 @@ int Launch(void) {
    timer.it_interval.tv_sec = timeout;
    setitimer(ITIMER_REAL, &timer, 0);
  }
-  if ((pid = vfork()) == -1) exit(errno);
+  pid = fork();
+
+#if 0
+  int fd;
+  size_t n;
+  char b[1024], *p;
+  size_t t = strlen(cmd) + 1 + TallyArgs(args.p) + 9 + TallyArgs(env.p) + 9;
+  n = ksnprintf(b, sizeof(b), "%ld %s %s\n", t, cmd, outpath);
+  fd = open("o/argmax.txt", O_APPEND | O_CREAT | O_WRONLY, 0644);
+  write(fd, b, n);
+  close(fd);
+#endif
+
  if (!pid) {
    SetCpuLimit(cpuquota);
    SetFszLimit(fszquota);
@ -508,7 +596,7 @@ int Launch(void) {
    dup2(pipefds[1], 2);
    sigprocmask(SIG_SETMASK, &savemask, 0);
    execve(cmd, args.p, env.p);
-    _exit(127);
+    _Exit(127);
  }
  close(pipefds[1]);
  for (;;) {
@ -609,21 +697,42 @@ void ReportResources(void) {
  appendw(&output, '\n');
 }

+bool IsNativeExecutable(const char *path) {
+  bool res;
+  char buf[4];
+  int got, fd;
+  res = false;
+  if ((fd = open(path, O_RDONLY)) != -1) {
+    if ((got = read(fd, buf, 4)) == 4) {
+      if (IsWindows()) {
+        res = READ16LE(buf) == READ16LE("MZ");
+      } else if (IsXnu()) {
+        res = READ32LE(buf) == 0xFEEDFACEu + 1;
+      } else {
+        res = READ32LE(buf) == READ32LE("\177ELF");
+      }
+    }
+    close(fd);
+  }
+  return res;
+}
+
 int main(int argc, char *argv[]) {
  int columns;
  uint64_t us;
+  bool isineditor;
  size_t i, j, n, m;
  bool isproblematic;
-  char *s, *p, **envp;
  int ws, opt, exitcode;
+  char *s, *p, *q, **envp;

  /*
   * parse prefix arguments
   */
  mode = MODE;
  verbose = 4;
-  timeout = 64;                 /* secs */
-  cpuquota = 8;                 /* secs */
+  timeout = 90;                 /* secs */
+  cpuquota = 16;                /* secs */
  fszquota = 100 * 1000 * 1000; /* bytes */
  memquota = 512 * 1024 * 1024; /* bytes */
  if ((s = getenv("V"))) verbose = atoi(s);
@ -876,6 +985,8 @@ int main(int argc, char *argv[]) {
    if (wantframe) {
      AddArg("-fno-omit-frame-pointer");
      AddArg("-D__FNO_OMIT_FRAME_POINTER__");
+    } else {
+      AddArg("-fomit-frame-pointer");
    }
  }

@ -938,6 +1049,7 @@ int main(int argc, char *argv[]) {
        exit(97);
      }
    }
+    args.p[0] = cmd;
  }

  /*
@ -991,7 +1103,8 @@ int main(int argc, char *argv[]) {
   * cleanup temporary copy of ape executable
   */
  if (originalcmd) {
-    if (cachedcmd && WIFEXITED(ws) && !WEXITSTATUS(ws)) {
+    if (cachedcmd && WIFEXITED(ws) && !WEXITSTATUS(ws) &&
+        IsNativeExecutable(cmd)) {
      makedirs(xdirname(cachedcmd), 0755);
      rename(cmd, cachedcmd);
    } else {
@ -1036,6 +1149,17 @@ int main(int argc, char *argv[]) {
      appends(&output, strsignal(WTERMSIG(ws)));
      PrintReset();
      appendw(&output, READ16LE(":\n"));
+      appends(&output, "env -i ");
+      for (i = 0; i < env.n; ++i) {
+        if (ArgNeedsShellQuotes(env.p[i])) {
+          q = AddShellQuotes(env.p[i]);
+          appends(&output, q);
+          free(q);
+        } else {
+          appends(&output, env.p[i]);
+        }
+        appendw(&output, ' ');
+      }
    }
  } else {
    exitcode = 89;
@ -1170,10 +1294,19 @@ int main(int argc, char *argv[]) {
      if (verbose < 2 || verbose == 3) {
        command = shortened;
      }
-      m = GetLineWidth();
+      m = GetLineWidth(&isineditor);
      if (m > n + 3 && appendz(command).i > m - n) {
-        appendd(&output, command, m - n - 3);
-        appendw(&output, READ32LE("..."));
+        if (isineditor) {
+          if (m > n + 3 && appendz(shortened).i > m - n) {
+            appendd(&output, shortened, m - n - 3);
+            appendw(&output, READ32LE("..."));
+          } else {
+            appendd(&output, shortened, appendz(shortened).i);
+          }
+        } else {
+          appendd(&output, command, m - n - 3);
+          appendw(&output, READ32LE("..."));
+        }
      } else {
        appendd(&output, command, appendz(command).i);
      }
--- a/tool/build/lib/diself.c
+++ b/tool/build/lib/diself.c
@ -23,6 +23,7 @@
 #include "libc/log/log.h"
 #include "libc/macros.internal.h"
 #include "libc/mem/mem.h"
+#include "libc/runtime/memtrack.internal.h"
 #include "libc/str/str.h"
 #include "tool/build/lib/dis.h"

@ -86,8 +87,7 @@ static void DisLoadElfSyms(struct Dis *d, struct Elf *elf) {
          ELF64_ST_TYPE(st[i].st_info) == STT_FILE || !st[i].st_name ||
          startswith(d->syms.stab + st[i].st_name, "v_") ||
          !(0 <= st[i].st_name && st[i].st_name < stablen) || !st[i].st_value ||
-          !(-0x800000000000 <= (int64_t)st[i].st_value &&
-            (int64_t)st[i].st_value < 0x800000000000)) {
+          !IsLegalPointer(st[i].st_value)) {
        continue;
      }
      isabs = st[i].st_shndx == SHN_ABS;
--- a/tool/build/lib/disspec.c
+++ b/tool/build/lib/disspec.c
@ -237,6 +237,8 @@ const char *DisSpecMap0(struct XedDecodedInst *x, char *p) {
    RCASE(0xCB, "lret");
    RCASE(0xCC, "int3");
    RCASE(0xCD, "int Ib");
+    RCASE(0xCE, "into");
+    RCASE(0xCF, "iret");
    RCASE(0xD0, "BIT Eb");
    RCASE(0xD1, "BIT Evqp");
    RCASE(0xD2, "BIT Evqp %cl");
--- a/tool/build/lib/eztls.c
+++ b/tool/build/lib/eztls.c
@ -159,6 +159,25 @@ void EzHandshake(void) {
  }
 }

+int EzHandshake2(void) {
+  int rc;
+  while ((rc = mbedtls_ssl_handshake(&ezssl))) {
+    if (rc == MBEDTLS_ERR_NET_CONN_RESET) {
+      return rc;
+    } else if (rc != MBEDTLS_ERR_SSL_WANT_READ) {
+      TlsDie("handshake failed", rc);
+    }
+  }
+  while ((rc = EzTlsFlush(&ezbio, 0, 0))) {
+    if (rc == MBEDTLS_ERR_NET_CONN_RESET) {
+      return rc;
+    } else if (rc != MBEDTLS_ERR_SSL_WANT_READ) {
+      TlsDie("handshake flush failed", rc);
+    }
+  }
+  return 0;
+}
+
 void EzInitialize(void) {
  xsigaction(SIGPIPE, SIG_IGN, 0, 0, 0);
  ezconf.disable_compression = 1; /* TODO(jart): Why does it behave weirdly? */
--- a/tool/build/lib/eztls.h
+++ b/tool/build/lib/eztls.h
@ -20,6 +20,7 @@ extern mbedtls_ctr_drbg_context ezrng;

 void EzFd(int);
 void EzHandshake(void);
+int EzHandshake2(void);
 void EzSetup(char[32]);
 void EzInitialize(void);
 int EzTlsFlush(struct EzTlsBio *, const unsigned char *, size_t);
--- a/tool/build/lib/fds.h
+++ b/tool/build/lib/fds.h
@ -1,6 +1,7 @@
 #ifndef COSMOPOLITAN_TOOL_BUILD_LIB_FDS_H_
 #define COSMOPOLITAN_TOOL_BUILD_LIB_FDS_H_
 #include "libc/calls/struct/iovec.h"
+#include "libc/sock/sock.h"
 #if !(__ASSEMBLER__ + __LINKER__ + 0)
 COSMOPOLITAN_C_START_

@ -14,17 +15,18 @@ struct MachineFdCb {
  ssize_t (*readv)(int, const struct iovec *, int);
  ssize_t (*writev)(int, const struct iovec *, int);
  int (*ioctl)(int, uint64_t, void *);
+  int (*poll)(struct pollfd *, uint64_t, int32_t);
 };

 struct MachineFd {
  int fd;
-  struct MachineFdCb * cb;
+  struct MachineFdCb *cb;
 };

 struct MachineFds {
  size_t i, n;
-  struct MachineFd * p;
-  struct MachineFdClosed * closed;
+  struct MachineFd *p;
+  struct MachineFdClosed *closed;
 };

 int MachineFdAdd(struct MachineFds *);
--- a/tool/build/lib/ioports.c
+++ b/tool/build/lib/ioports.c
@ -17,8 +17,12 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/struct/iovec.h"
+#include "libc/dce.h"
+#include "libc/log/log.h"
 #include "libc/nexgen32e/uart.internal.h"
+#include "libc/sock/sock.h"
 #include "libc/sysv/consts/fileno.h"
+#include "libc/sysv/consts/poll.h"
 #include "tool/build/lib/ioports.h"

 static int OpE9Read(struct Machine *m) {
@ -42,7 +46,21 @@ static void OpE9Write(struct Machine *m, uint8_t b) {
  m->fds.p[fd].cb->writev(m->fds.p[fd].fd, &(struct iovec){&b, 1}, 1);
 }

+static int OpE9Poll(struct Machine *m) {
+  int fd, rc;
+  struct pollfd pf;
+  fd = STDIN_FILENO;
+  if (fd >= m->fds.i) return -1;
+  if (!m->fds.p[fd].cb) return -1;
+  pf.fd = m->fds.p[fd].fd;
+  pf.events = POLLIN | POLLOUT;
+  rc = m->fds.p[fd].cb->poll(&pf, 1, 20);
+  if (rc <= 0) return rc;
+  return pf.revents;
+}
+
 static int OpSerialIn(struct Machine *m, int r) {
+  int p, s;
  switch (r) {
    case UART_DLL:
      if (!m->dlab) {
@ -51,7 +69,15 @@ static int OpSerialIn(struct Machine *m, int r) {
        return 0x01;
      }
    case UART_LSR:
-      return UART_TTYDA | UART_TTYTXR | UART_TTYIDL;
+      if (IsWindows()) {
+        p = POLLIN | POLLOUT; /* XXX */
+      } else {
+        if ((p = OpE9Poll(m)) == -1) return -1;
+      }
+      s = UART_TTYIDL;
+      if (p & POLLIN) s |= UART_TTYDA;
+      if (p & POLLOUT) s |= UART_TTYTXR;
+      return s;
    default:
      return 0;
  }
--- a/tool/build/lib/loader.c
+++ b/tool/build/lib/loader.c
@ -43,7 +43,7 @@ static void LoadElfLoadSegment(struct Machine *m, void *code, size_t codesize,
  int64_t align, bsssize;
  int64_t felf, fstart, fend, vstart, vbss, vend;
  align = MAX(phdr->p_align, PAGESIZE);
-  CHECK_EQ(1, popcnt(align));
+  if (popcnt(align) != 1) align = 8;
  CHECK_EQ(0, (phdr->p_vaddr - phdr->p_offset) % align);
  felf = (int64_t)(intptr_t)code;
  vstart = ROUNDDOWN(phdr->p_vaddr, align);
--- a/tool/build/lib/machine.c
+++ b/tool/build/lib/machine.c
@ -288,6 +288,12 @@ static void OpJmpf(struct Machine *m, uint32_t rde) {
  }
 }

+static void OpInto(struct Machine *m, uint32_t rde) {
+  if (GetFlag(m->flags, FLAGS_OF)) {
+    HaltMachine(m, kMachineOverflow);
+  }
+}
+
 static relegated void OpXlatAlBbb(struct Machine *m, uint32_t rde) {
  uint64_t v;
  v = MaskAddress(Eamode(rde), Read64(m->bx) + Read8(m->ax));
@ -1888,7 +1894,7 @@ static const nexgen32e_f kNexgen32e[] = {
    [0x0CB] = OpRetf,
    [0x0CC] = OpInterrupt3,
    [0x0CD] = OpInterruptImm,
-    [0x0CE] = OpUd,
+    [0x0CE] = OpInto,
    [0x0CF] = OpUd,
    [0x0D0] = OpBsubi1,
    [0x0D1] = OpBsuwi1,
--- a/tool/build/lib/machine.h
+++ b/tool/build/lib/machine.h
@ -13,6 +13,7 @@
 #define kMachineFpuException         -7
 #define kMachineProtectionFault      -8
 #define kMachineSimdException        -9
+#define kMachineOverflow             -10

 #if !(__ASSEMBLER__ + __LINKER__ + 0)
 COSMOPOLITAN_C_START_
--- a/tool/build/lib/memory.c
+++ b/tool/build/lib/memory.c
@ -21,6 +21,7 @@
 #include "libc/log/log.h"
 #include "libc/macros.internal.h"
 #include "libc/mem/mem.h"
+#include "libc/runtime/memtrack.internal.h"
 #include "libc/runtime/pc.internal.h"
 #include "libc/str/str.h"
 #include "libc/x/x.h"
@ -90,7 +91,7 @@ void *FindReal(struct Machine *m, int64_t virt) {
  uint64_t table, entry, page;
  unsigned skew, level, index, i;
  if ((m->mode & 3) != XED_MODE_REAL) {
-    if (-0x800000000000 <= virt && virt < 0x800000000000) {
+    if (IsLegalPointer(virt)) {
      if (!(entry = FindPage(m, virt))) return NULL;
      return m->real.p + (entry & PAGE_TA) + (virt & 0xfff);
    } else {
--- a/tool/build/lib/pty.c
+++ b/tool/build/lib/pty.c
@ -1167,10 +1167,45 @@ ssize_t PtyWrite(struct Pty *pty, const void *data, size_t n) {
 }

 ssize_t PtyWriteInput(struct Pty *pty, const void *data, size_t n) {
-  PtyConcatInput(pty, data, n);
-  if (!(pty->conf & kPtyNoecho)) {
-    PtyWrite(pty, data, n);
+  int c;
+  bool cr;
+  char *p;
+  const char *q;
+  size_t i, j, m;
+  q = data;
+  p = pty->input.p;
+  i = pty->input.i;
+  m = pty->input.n;
+  if (i + n * 2 + 1 > m) {
+    m = MAX(m, 8);
+    do m += m >> 1;
+    while (i + n * 2 + 1 > m);
+    if (!(p = realloc(p, m))) {
+      return -1;
+    }
+    pty->input.p = p;
+    pty->input.n = m;
  }
+  cr = i && p[i - 1] == '\r';
+  for (j = 0; j < n; ++j) {
+    c = q[j] & 255;
+    if (c == '\r') {
+      cr = true;
+    } else if (cr) {
+      if (c != '\n') {
+        p[i++] = '\n';
+      }
+      cr = false;
+    }
+    p[i++] = c;
+  }
+  if (cr) {
+    p[i++] = '\n';
+  }
+  if (!(pty->conf & kPtyNoecho)) {
+    PtyWrite(pty, p + pty->input.i, i - pty->input.i);
+  }
+  pty->input.i = i;
  return n;
 }

--- a/tool/build/lib/syscall.c
+++ b/tool/build/lib/syscall.c
@ -102,6 +102,7 @@
 const struct MachineFdCb kMachineFdCbHost = {
    .close = close,
    .readv = readv,
+    .poll = poll,
    .writev = writev,
    .ioctl = (void *)ioctl,
 };
--- a/tool/build/lib/time.c
+++ b/tool/build/lib/time.c
@ -18,7 +18,9 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
 #include "libc/nexgen32e/rdtsc.h"
+#include "libc/sock/sock.h"
 #include "libc/sysv/consts/clock.h"
+#include "libc/sysv/consts/poll.h"
 #include "libc/time/time.h"
 #include "tool/build/lib/endian.h"
 #include "tool/build/lib/modrm.h"
@ -29,7 +31,19 @@
 */

 void OpPause(struct Machine *m, uint32_t rde) {
-  sched_yield();
+  struct pollfd pf;
+  static bool once, interactive;
+  if (!once) {
+    interactive = isatty(0);
+    once = true;
+  }
+  if (!IsWindows() && interactive) {
+    pf.fd = 0;
+    pf.events = POLLIN;
+    poll(&pf, 1, 20); /* make spin loops less brutal */
+  } else {
+    sched_yield();
+  }
 }

 void OpRdtsc(struct Machine *m, uint32_t rde) {
--- a/tool/build/package.c
+++ b/tool/build/package.c
@ -53,6 +53,7 @@
 #include "third_party/xed/x86.h"
 #include "third_party/zlib/zlib.h"
 #include "tool/build/lib/elfwriter.h"
+#include "tool/build/lib/getargs.h"
 #include "tool/build/lib/persist.h"

 /**
@ -62,14 +63,14 @@
 *
 * This script verifies the well-formedness of dependencies, e.g.
 *
- *   o/tool/build/package.com \
- *     -o o/libc/stubs/stubs.pkg \
- *     o/libc/stubs/{a,b,...}.o
+ *     o/tool/build/package.com \
+ *       -o o/libc/stubs/stubs.pkg \
+ *       o/libc/stubs/{a,b,...}.o
 *
- *   o/tool/build/package.com \
- *     -o o/libc/nexgen32e/nexgen32e.pkg \
- *     -d o/libc/stubs/stubs.pkg \
- *     o/libc/nexgen32e/{a,b,...}.o
+ *     o/tool/build/package.com \
+ *       -o o/libc/nexgen32e/nexgen32e.pkg \
+ *       -d o/libc/stubs/stubs.pkg \
+ *       o/libc/nexgen32e/{a,b,...}.o
 *
 * We want the following:
 *
@ -84,21 +85,30 @@
 *
 * SECOND PURPOSE
 *
- * We want all storage to be thread-local storage. So we change
- * RIP-relative instructions to be RBX-relative, only when they
- * reference sections in the binary mutable after initialization.
- *
- * This is basically what the Go language does to implement its fiber
- * multiprocessing model. We can have this in C by appropriating all the
- * work folks put into enriching GNU C with WIN32 and ASLR lool.
- *
- * THIRD PURPOSE
- *
 * Compress read-only data sections of particularly low entropy, using
 * the most appropriate directly-linked algorithm and then inject code
 * into _init() that calls it. If the data is extremely low energy, we
 * will inject code for merging page table entries too. The overcommit
 * here is limitless.
+ *
+ * POSSIBLE PURPOSE
+ *
+ * It might be nice to have all storage to be thread-local storage. So
+ * we change RIP-relative instructions to be RBX-relative, only when
+ * they reference sections in the binary mutable after initialization.
+ *
+ * This is basically what the Go language does to implement its fiber
+ * multiprocessing model. We can have this in C by appropriating all the
+ * work folks put into enriching GNU C with WIN32 and ASLR lool.
+ *
+ * CAVEATS
+ *
+ * This tool monkey patches `.o` files as a side-effect since we're not
+ * able to modify the GCC source code. Therefore it's VERY IMPORTANT to
+ * have Makefile rules which build `.a` or `.com.dbg` *depend* upon the
+ * `.pkg` rule. That way they happen in the right order. Otherwise they
+ * might build binaries with compromised profiling nops at the start of
+ * functions, which will almost certainly result in SIGILL.
 */

 #define PACKAGE_MAGIC bswap_32(0xBEEFBEEFu)
@ -226,6 +236,8 @@ void WritePackage(struct Package *pkg) {
 void GetOpts(struct Package *pkg, struct Packages *deps, int argc,
             char *argv[]) {
  long i, si, opt;
+  const char *arg;
+  struct GetArgs ga;
  pkg->path = -1;
  while ((opt = getopt(argc, argv, "vho:d:")) != -1) {
    switch (opt) {
@ -251,10 +263,12 @@ void GetOpts(struct Package *pkg, struct Packages *deps, int argc,
  CHECK_LT(optind, argc,
           "no objects passed to package.com; "
           "is your foo.mk $(FOO_OBJS) glob broken?");
-  for (i = optind; i < argc; ++i) {
-    CHECK_NE(-1, (si = concat(&pkg->strings, argv[i], strlen(argv[i]) + 1)));
+  getargs_init(&ga, argv + optind);
+  while ((arg = getargs_next(&ga))) {
+    CHECK_NE(-1, (si = concat(&pkg->strings, arg, strlen(arg) + 1)));
    CHECK_NE(-1, append(&pkg->objects, (&(struct Object){si})));
  }
+  getargs_destroy(&ga);
 }

 void IndexSections(struct Object *obj) {
@ -671,17 +685,17 @@ void Package(int argc, char *argv[], struct Package *pkg,
    }
    free(pkg->objects.p[i].sections.p);
  }
-  free_s(&pkg->strings.p);
-  free_s(&pkg->objects.p);
-  free_s(&pkg->symbols.p);
-  free_s(&deps->p);
+  free(pkg->strings.p);
+  free(pkg->objects.p);
+  free(pkg->symbols.p);
+  free(deps->p);
 }

 int main(int argc, char *argv[]) {
  struct Package pkg;
  struct Packages deps;
  if (argc == 2 && !strcmp(argv[1], "-n")) exit(0);
-  showcrashreports();
+  if (IsModeDbg()) ShowCrashReports();
  bzero(&pkg, sizeof(pkg));
  bzero(&deps, sizeof(deps));
  Package(argc, argv, &pkg, &deps);
--- a/tool/build/runit.c
+++ b/tool/build/runit.c
@ -22,18 +22,22 @@
 #include "libc/calls/calls.h"
 #include "libc/calls/sigbits.h"
 #include "libc/calls/struct/flock.h"
+#include "libc/dce.h"
 #include "libc/dns/dns.h"
 #include "libc/fmt/conv.h"
+#include "libc/intrin/kprintf.h"
 #include "libc/limits.h"
 #include "libc/log/check.h"
 #include "libc/log/log.h"
 #include "libc/macros.internal.h"
 #include "libc/nexgen32e/crc32.h"
 #include "libc/runtime/gc.internal.h"
+#include "libc/runtime/runtime.h"
 #include "libc/sock/ipclassify.internal.h"
 #include "libc/stdio/stdio.h"
 #include "libc/sysv/consts/af.h"
 #include "libc/sysv/consts/ex.h"
+#include "libc/sysv/consts/f.h"
 #include "libc/sysv/consts/fileno.h"
 #include "libc/sysv/consts/ipproto.h"
 #include "libc/sysv/consts/itimer.h"
@ -110,6 +114,8 @@ char g_hostname[128];
 uint16_t g_runitdport;
 volatile bool alarmed;

+int __sys_execve(const char *, char *const[], char *const[]) hidden;
+
 static void OnAlarm(int sig) {
  alarmed = true;
 }
@ -166,7 +172,7 @@ void DeployEphemeralRunItDaemonRemotelyViaSsh(struct addrinfo *ai) {
  mkdir("o", 0755);
  CHECK_NE(-1, (lock = open(gc(xasprintf("o/lock.%s", g_hostname)),
                            O_RDWR | O_CREAT, 0644)));
-  CHECK_NE(-1, flock(lock, LOCK_EX));
+  CHECK_NE(-1, fcntl(lock, F_SETLKW, &(struct flock){F_WRLCK}));
  CHECK_NE(-1, gettimeofday(&now, 0));
  if (!read(lock, &then, 16) || ((now.tv_sec * 1000 + now.tv_usec / 1000) -
                                 (then.tv_sec * 1000 + then.tv_usec / 1000)) >=
@ -232,6 +238,7 @@ void DeployEphemeralRunItDaemonRemotelyViaSsh(struct addrinfo *ai) {
  } else {
    DEBUGF("nospawn %s on %s:%hu", g_runitd, g_hostname, g_runitdport);
  }
+  CHECK_NE(-1, fcntl(lock, F_SETLK, &(struct flock){F_UNLCK}));
  LOGIFNEG1(close(lock));
 }

@ -376,6 +383,14 @@ drop:
  return res;
 }

+static inline bool IsElf(const char *p, size_t n) {
+  return n >= 4 && READ32LE(p) == READ32LE("\177ELF");
+}
+
+static inline bool IsMachO(const char *p, size_t n) {
+  return n >= 4 && READ32LE(p) == 0xFEEDFACEu + 1;
+}
+
 int RunOnHost(char *spec) {
  int rc;
  char *p;
@ -386,9 +401,13 @@ int RunOnHost(char *spec) {
           1);
  if (!strchr(g_hostname, '.')) strcat(g_hostname, ".test.");
  do {
-    Connect();
-    EzFd(g_sock);
-    EzHandshake(); /* TODO(jart): Backoff on MBEDTLS_ERR_NET_CONN_RESET */
+    for (;;) {
+      Connect();
+      EzFd(g_sock);
+      if (!EzHandshake2()) break;
+      WARNF("warning: got connection reset in handshake");
+      close(g_sock);
+    }
    SendRequest();
  } while ((rc = ReadResponse()) == -1);
  return rc;
@ -403,11 +422,14 @@ bool ShouldRunInParralel(void) {
  return !IsWindows() && IsParallelBuild();
 }

-int RunRemoteTestsInParallel(char *hosts[], int count) {
+int SpawnSubprocesses(int argc, char *argv[]) {
  sigset_t chldmask, savemask;
  int i, rc, ws, pid, *pids, exitcode;
  struct sigaction ignore, saveint, savequit;
-  pids = calloc(count, sizeof(char *));
+  char *args[5] = {argv[0], argv[1], argv[2]};
+  argc -= 3;
+  argv += 3;
+  pids = calloc(argc, sizeof(int));
  ignore.sa_flags = 0;
  ignore.sa_handler = SIG_IGN;
  LOGIFNEG1(sigemptyset(&ignore.sa_mask));
@ -416,13 +438,17 @@ int RunRemoteTestsInParallel(char *hosts[], int count) {
  LOGIFNEG1(sigemptyset(&chldmask));
  LOGIFNEG1(sigaddset(&chldmask, SIGCHLD));
  LOGIFNEG1(sigprocmask(SIG_BLOCK, &chldmask, &savemask));
-  for (i = 0; i < count; ++i) {
-    CHECK_NE(-1, (pids[i] = fork()));
+  for (i = 0; i < argc; ++i) {
+    args[3] = argv[i];
+    fprintf(stderr, "spawning %s %s %s %s\n", args[0], args[1], args[2],
+            args[3]);
+    CHECK_NE(-1, (pids[i] = vfork()));
    if (!pids[i]) {
-      sigaction(SIGINT, &saveint, NULL);
-      sigaction(SIGQUIT, &savequit, NULL);
-      sigprocmask(SIG_SETMASK, &savemask, NULL);
-      _exit(RunOnHost(hosts[i]));
+      xsigaction(SIGINT, SIG_DFL, 0, 0, 0);
+      xsigaction(SIGQUIT, SIG_DFL, 0, 0, 0);
+      sigprocmask(SIG_SETMASK, &savemask, 0);
+      execve(args[0], args, environ); /* for htop */
+      _exit(127);
    }
  }
  for (exitcode = 0;;) {
@ -431,13 +457,17 @@ int RunRemoteTestsInParallel(char *hosts[], int count) {
      if (errno == ECHILD) break;
      FATALF("wait failed");
    }
-    for (i = 0; i < count; ++i) {
+    for (i = 0; i < argc; ++i) {
      if (pids[i] != pid) continue;
      if (WIFEXITED(ws)) {
-        DEBUGF("%s exited with %d", hosts[i], WEXITSTATUS(ws));
+        if (WEXITSTATUS(ws)) {
+          INFOF("%s exited with %d", argv[i], WEXITSTATUS(ws));
+        } else {
+          DEBUGF("%s exited with %d", argv[i], WEXITSTATUS(ws));
+        }
        if (!exitcode) exitcode = WEXITSTATUS(ws);
      } else {
-        DEBUGF("%s terminated with %s", hosts[i], strsignal(WTERMSIG(ws)));
+        INFOF("%s terminated with %s", argv[i], strsignal(WTERMSIG(ws)));
        if (!exitcode) exitcode = 128 + WTERMSIG(ws);
      }
      break;
@ -447,24 +477,36 @@ int RunRemoteTestsInParallel(char *hosts[], int count) {
  LOGIFNEG1(sigaction(SIGQUIT, &savequit, NULL));
  LOGIFNEG1(sigprocmask(SIG_SETMASK, &savemask, NULL));
  free(pids);
+  kprintf("nocommit%n");
  return exitcode;
 }

 int main(int argc, char *argv[]) {
  ShowCrashReports();
-  SetupPresharedKeySsl(MBEDTLS_SSL_IS_CLIENT, GetRunitPsk());
-  /* __log_level = kLogDebug; */
+  __log_level = kLogDebug;
  if (argc > 1 &&
      (strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--help") == 0)) {
    ShowUsage(stdout, 0);
    unreachable;
  }
-  if (argc < 1 + 2) ShowUsage(stderr, EX_USAGE);
-  CHECK_NOTNULL(commandv(firstnonnull(getenv("SSH"), "ssh"), g_ssh));
+  if (argc < 3) {
+    ShowUsage(stderr, EX_USAGE);
+    unreachable;
+  }
  CheckExists((g_runitd = argv[1]));
  CheckExists((g_prog = argv[2]));
-  if (argc == 1 + 2) return 0; /* hosts list empty */
-  g_sshport = 22;
-  g_runitdport = RUNITD_PORT;
-  return RunRemoteTestsInParallel(&argv[3], argc - 3);
+  CHECK_NOTNULL(commandv(firstnonnull(getenv("SSH"), "ssh"), g_ssh));
+  if (argc == 3) {
+    /* hosts list empty */
+    return 0;
+  } else if (argc == 4) {
+    /* single host */
+    SetupPresharedKeySsl(MBEDTLS_SSL_IS_CLIENT, GetRunitPsk());
+    g_sshport = 22;
+    g_runitdport = RUNITD_PORT;
+    return RunOnHost(argv[3]);
+  } else {
+    /* multiple hosts */
+    return SpawnSubprocesses(argc, argv);
+  }
 }
--- a/tool/build/runitd.c
+++ b/tool/build/runitd.c
@ -87,7 +87,7 @@
 *   - 1 byte exit status
 */

-#define DEATH_CLOCK_SECONDS 5
+#define DEATH_CLOCK_SECONDS 16

 #define kLogFile     "o/runitd.log"
 #define kLogMaxBytes (2 * 1000 * 1000)
@ -339,6 +339,8 @@ void HandleClient(void) {
    dup2(g_devnullfd, 0);
    dup2(pipefds[1], 1);
    dup2(pipefds[1], 2);
+    if (pipefds[0] > 2) close(pipefds[1]);
+    if (g_devnullfd > 2) close(g_devnullfd);
    execv(g_exepath, (char *const[]){g_exepath, NULL});
    _exit(127);
  }