Make improvements

- Add rusage to redbean Lua API
- Add more redbean documentation
- Add pledge() to redbean Lua API
- Polyfill OpenBSD pledge() for Linux
- Increase PATH_MAX limit to 1024 characters
- Untrack sibling processes after fork() on Windows

libc/runtime/findcombinary.c

@@ -24,7 +24,7 @@
 struct FindComBinary {
   bool once;
   const char *res;
-  char buf[PATH_MAX + 1];
+  char buf[PATH_MAX];
 };
 
 static struct FindComBinary g_findcombinary;

libc/runtime/finddebugbinary.c

@@ -18,6 +18,7 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/bits/bits.h"
 #include "libc/calls/calls.h"
+#include "libc/macros.internal.h"
 #include "libc/runtime/runtime.h"
 #include "libc/runtime/symbols.internal.h"
 #include "libc/str/str.h"
@@ -30,7 +31,7 @@
 const char *FindDebugBinary(void) {
   static bool once;
   static char *res;
-  static char buf[PATH_MAX + 1];
+  static char buf[PATH_MAX];
   char *p;
   size_t n;
   if (!once) {
@@ -40,12 +41,12 @@ const char *FindDebugBinary(void) {
       if (n > 4 && READ32LE(p + n - 4) == READ32LE(".dbg")) {
         res = p;
       } else if (n > 4 && READ32LE(p + n - 4) == READ32LE(".com") &&
-                 n + 4 <= PATH_MAX) {
+                 n + 4 < ARRAYLEN(buf)) {
         mempcpy(mempcpy(buf, p, n), ".dbg", 5);
         if (fileexists(buf)) {
           res = buf;
         }
-      } else if (n + 8 <= PATH_MAX) {
+      } else if (n + 8 < ARRAYLEN(buf)) {
         mempcpy(mempcpy(buf, p, n), ".com.dbg", 9);
         if (fileexists(buf)) {
           res = buf;

libc/runtime/fork-nt.c

@@ -212,9 +212,18 @@ textwindows void WinMainForked(void) {
   // since the handles closed on fork
   if (weaken(ForkNtStdinWorker)) weaken(ForkNtStdinWorker)();
   struct Fds *fds = VEIL("r", &g_fds);
-  fds->__init_p[0].handle = GetStdHandle(kNtStdInputHandle);
-  fds->__init_p[1].handle = GetStdHandle(kNtStdOutputHandle);
-  fds->__init_p[2].handle = GetStdHandle(kNtStdErrorHandle);
+  fds->p[0].handle = fds->__init_p[0].handle = GetStdHandle(kNtStdInputHandle);
+  fds->p[1].handle = fds->__init_p[1].handle = GetStdHandle(kNtStdOutputHandle);
+  fds->p[2].handle = fds->__init_p[2].handle = GetStdHandle(kNtStdErrorHandle);
+
+  // untrack the forked children of the parent since we marked the
+  // CreateProcess() process handle below as non-inheritable
+  for (i = 0; i < fds->n; ++i) {
+    if (fds->p[i].kind == kFdProcess) {
+      fds->p[i].kind = 0;
+      fds->f = MIN(i, fds->f);
+    }
+  }
 
   // restore the crash reporting stuff
   if (weaken(__wincrash_nt)) {
@@ -269,9 +278,8 @@ textwindows int sys_fork_nt(void) {
         args = args2;
       }
 #endif
-      if (ntspawn(GetProgramExecutableName(), args, environ, forkvar,
-                  &kNtIsInheritable, NULL, true, 0, NULL, &startinfo,
-                  &procinfo) != -1) {
+      if (ntspawn(GetProgramExecutableName(), args, environ, forkvar, 0, 0,
+                  true, 0, 0, &startinfo, &procinfo) != -1) {
         CloseHandle(procinfo.hThread);
         ok = WriteAll(writer, jb, sizeof(jb)) &&
              WriteAll(writer, &_mmi.i, sizeof(_mmi.i)) &&

libc/runtime/getargmax.c

@@ -0,0 +1,33 @@
+/*-*- 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 2022 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/dce.h"
+#include "libc/runtime/runtime.h"
+
+/**
+ * Returns `ARG_MAX` for host platform.
+ */
+int __arg_max(void) {
+  if (IsWindows()) return 32767;
+  if (IsLinux()) return 128 * 1024;
+  if (IsNetbsd()) return 256 * 1024;
+  if (IsFreebsd()) return 512 * 1024;
+  if (IsOpenbsd()) return 512 * 1024;
+  if (IsXnu()) return 1024 * 1024;
+  return ARG_MAX;
+}

libc/runtime/mprotect-nt.greg.c

@@ -24,7 +24,7 @@
 
 #define ADDR(x) ((char *)((int64_t)((uint64_t)(x) << 32) >> 16))
 
-privileged int sys_mprotect_nt(void *addr, size_t size, int prot) {
+textwindows int sys_mprotect_nt(void *addr, size_t size, int prot) {
   int rc = 0;
   unsigned i;
   uint32_t op;

libc/runtime/paginate.c

@@ -30,8 +30,8 @@
 void __paginate(int fd, const char *s) {
   int tfd, pid;
   char *args[3] = {0};
-  char tmppath[PATH_MAX + 1];
-  char progpath[PATH_MAX + 1];
+  char tmppath[PATH_MAX];
+  char progpath[PATH_MAX];
   if (strcmp(nulltoempty(getenv("TERM")), "dumb") && isatty(0) && isatty(1) &&
       ((args[0] = commandv("less", progpath, sizeof(progpath))) ||
        (args[0] = commandv("more", progpath, sizeof(progpath))))) {

libc/runtime/printargs.greg.c

@@ -140,10 +140,13 @@ textstartup void __printargs(const char *prologue) {
   uintptr_t *auxp;
   struct utsname uts;
   struct termios termios;
-  char path[PATH_MAX + 1];
   int e, x, st, ft, flags;
-  struct pollfd pfds[128];
   struct AuxiliaryValue *auxinfo;
+  union {
+    char path[PATH_MAX];
+    struct pollfd pfds[128];
+  } u;
+
   st = __strace, __strace = 0;
   ft = g_ftrace, g_ftrace = 0;
   e = errno;
@@ -240,15 +243,15 @@ textstartup void __printargs(const char *prologue) {
 
   PRINT("");
   PRINT("FILE DESCRIPTORS");
-  for (i = 0; i < ARRAYLEN(pfds); ++i) {
-    pfds[i].fd = i;
-    pfds[i].events = POLLIN;
+  for (i = 0; i < ARRAYLEN(u.pfds); ++i) {
+    u.pfds[i].fd = i;
+    u.pfds[i].events = POLLIN;
   }
-  if ((n = poll(pfds, ARRAYLEN(pfds), 0)) != -1) {
-    for (i = 0; i < ARRAYLEN(pfds); ++i) {
-      if (i && (pfds[i].revents & POLLNVAL)) continue;
+  if ((n = poll(u.pfds, ARRAYLEN(u.pfds), 0)) != -1) {
+    for (i = 0; i < ARRAYLEN(u.pfds); ++i) {
+      if (i && (u.pfds[i].revents & POLLNVAL)) continue;
       PRINT(" ☼ %d (revents=%#hx fcntl(F_GETFL)=%#x isatty()=%hhhd)", i,
-            pfds[i].revents, fcntl(i, F_GETFL), isatty(i));
+            u.pfds[i].revents, fcntl(i, F_GETFL), isatty(i));
     }
   } else {
     PRINT("  poll() returned %d %m", n);
@@ -298,8 +301,8 @@ textstartup void __printargs(const char *prologue) {
     if (*__auxv) {
       for (auxp = __auxv; *auxp; auxp += 2) {
         if ((auxinfo = DescribeAuxv(auxp[0]))) {
-          ksnprintf(path, sizeof(path), auxinfo->fmt, auxp[1]);
-          PRINT(" ☼ %16s[%4ld] = %s", auxinfo->name, auxp[0], path);
+          ksnprintf(u.path, sizeof(u.path), auxinfo->fmt, auxp[1]);
+          PRINT(" ☼ %16s[%4ld] = %s", auxinfo->name, auxp[0], u.path);
         } else {
           PRINT(" ☼ %16s[%4ld] = %014p", "unknown", auxp[0], auxp[1]);
         }
@@ -326,7 +329,7 @@ textstartup void __printargs(const char *prologue) {
   PRINT(" ☼ %s = %#s", "kNtWindowsDirectory", kNtWindowsDirectory);
   PRINT(" ☼ %s = %#s", "GetProgramExecutableName", GetProgramExecutableName());
   PRINT(" ☼ %s = %#s", "GetInterpreterExecutableName",
-        GetInterpreterExecutableName(path, sizeof(path)));
+        GetInterpreterExecutableName(u.path, sizeof(u.path)));
   PRINT(" ☼ %s = %p", "RSP", __builtin_frame_address(0));
   PRINT(" ☼ %s = %p", "GetStackAddr()", GetStackAddr(0));
   PRINT(" ☼ %s = %p", "GetStaticStackAddr(0)", GetStaticStackAddr(0));

libc/runtime/runtime.h

@@ -104,6 +104,7 @@ char *GetProgramExecutableName(void);
 char *GetInterpreterExecutableName(char *, size_t);
 void __printargs(const char *);
 void __paginate(int, const char *);
+int __arg_max(void);
 
 COSMOPOLITAN_C_END_
 #endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */

libc/runtime/sysconf.c

@@ -22,6 +22,7 @@
 #include "libc/macros.internal.h"
 #include "libc/runtime/clktck.h"
 #include "libc/runtime/sysconf.h"
+#include "libc/sysv/consts/limits.h"
 #include "libc/sysv/consts/rlim.h"
 #include "libc/sysv/consts/rlimit.h"
 
@@ -42,7 +43,7 @@ long sysconf(int name) {
   int n;
   switch (name) {
     case _SC_ARG_MAX:
-      return ARG_MAX;
+      return _ARG_MAX;
     case _SC_CHILD_MAX:
       return GetResourceLimit(RLIMIT_NPROC);
     case _SC_CLK_TCK:

libc/runtime/winmain.greg.c

@@ -84,8 +84,8 @@ struct WinArgs {
   char *argv[4096];
   char *envp[4092];
   intptr_t auxv[2][2];
-  char argblock[ARG_MAX];
-  char envblock[ARG_MAX];
+  char argblock[ARG_MAX / 2];
+  char envblock[ARG_MAX / 2];
 };
 
 extern uint32_t __winmainpid;