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

test/libc/calls/commandv_test.c

@@ -35,8 +35,8 @@
 
 uint64_t i;
 char *oldpath;
-char tmp[PATH_MAX + 1];
-char pathbuf[PATH_MAX + 1];
+char tmp[PATH_MAX];
+char pathbuf[PATH_MAX];
 char testlib_enable_tmp_setup_teardown;
 
 void SetUp(void) {

test/libc/calls/getcwd_test.c

@@ -43,7 +43,7 @@ TEST(getcwd, testNullBuf_allocatesResult) {
 
 TEST(getcwd, testWindows_addsFunnyPrefix) {
   if (!IsWindows()) return;
-  char path[PATH_MAX + 1];
+  char path[PATH_MAX];
   ASSERT_NE(0, getcwd(path, sizeof(path)));
   EXPECT_STARTSWITH("//?/", path);
 }

test/libc/calls/mkntcmdline_test.c

@@ -23,7 +23,7 @@
 #include "libc/str/str.h"
 #include "libc/testlib/testlib.h"
 
-char16_t cmdline[ARG_MAX];
+char16_t cmdline[ARG_MAX / 2];
 
 TEST(mkntcmdline, emptyArgvList_cantBeEmptyOnWindows) {
   char *argv[] = {NULL};

test/libc/calls/mkntenvblock_test.c

@@ -20,7 +20,7 @@
 #include "libc/runtime/gc.internal.h"
 #include "libc/testlib/testlib.h"
 
-char16_t envvars[ARG_MAX];
+char16_t envvars[ARG_MAX / 2];
 
 TEST(mkntenvblock, emptyList_onlyOutputsDoubleNulStringTerminator) {
   char *envp[] = {NULL};

test/libc/calls/seccomp_test.c

@@ -17,6 +17,7 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
+#include "libc/calls/internal.h"
 #include "libc/calls/struct/bpf.h"
 #include "libc/calls/struct/filter.h"
 #include "libc/calls/struct/iovec.h"
@@ -31,16 +32,6 @@
 #include "libc/testlib/testlib.h"
 #include "tool/net/sandbox.h"
 
-bool __is_linux_2_6_23(void) {
-  int rc;
-  if (!IsLinux()) return false;
-  asm volatile("syscall"
-               : "=a"(rc)
-               : "0"(157), "D"(PR_GET_SECCOMP)
-               : "rcx", "r11", "memory");
-  return rc != -EINVAL;
-}
-
 void SetUp(void) {
   if (!__is_linux_2_6_23()) {
     exit(0);

test/libc/mem/pledge_test.c

@@ -0,0 +1,62 @@
+/*-*- 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/calls/calls.h"
+#include "libc/calls/internal.h"
+#include "libc/dce.h"
+#include "libc/errno.h"
+#include "libc/mem/mem.h"
+#include "libc/runtime/runtime.h"
+#include "libc/sysv/consts/o.h"
+#include "libc/testlib/testlib.h"
+
+void SetUp(void) {
+  if (!__is_linux_2_6_23() && !IsOpenbsd()) {
+    exit(0);
+  }
+}
+
+TEST(pledge, default_allowsExit) {
+  int ws, pid;
+  ASSERT_NE(-1, (pid = fork()));
+  if (!pid) {
+    ASSERT_SYS(0, 0, pledge("", 0));
+    _Exit(0);
+  }
+  EXPECT_NE(-1, wait(&ws));
+  EXPECT_TRUE(WIFEXITED(ws));
+  EXPECT_EQ(0, WEXITSTATUS(ws));
+}
+
+TEST(pledge, stdio_forbidsOpeningPasswd) {
+  int ws, pid;
+  ASSERT_NE(-1, (pid = fork()));
+  if (!pid) {
+    ASSERT_SYS(0, 0, pledge("stdio", 0));
+    ASSERT_SYS(EPERM, -1, open("/etc/passwd", O_RDWR));
+    _Exit(0);
+  }
+  EXPECT_NE(-1, wait(&ws));
+  if (IsLinux()) {
+    EXPECT_TRUE(WIFEXITED(ws));
+    EXPECT_EQ(0, WEXITSTATUS(ws));
+  } else {
+    EXPECT_TRUE(WIFSIGNALED(ws));
+    EXPECT_EQ(SIGABRT, WTERMSIG(ws));
+  }
+}

test/libc/runtime/fork_test.c

@@ -17,11 +17,16 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
+#include "libc/calls/sigbits.h"
+#include "libc/calls/struct/sigaction.h"
+#include "libc/dce.h"
+#include "libc/log/check.h"
 #include "libc/macros.internal.h"
 #include "libc/runtime/runtime.h"
 #include "libc/sysv/consts/map.h"
 #include "libc/sysv/consts/msync.h"
 #include "libc/sysv/consts/prot.h"
+#include "libc/sysv/consts/sig.h"
 #include "libc/testlib/ezbench.h"
 #include "libc/testlib/testlib.h"
 
@@ -79,6 +84,51 @@ TEST(fork, testSharedMemory) {
   EXPECT_NE(-1, munmap(privatevar, FRAMESIZE));
 }
 
+static volatile bool gotsigusr1;
+static volatile bool gotsigusr2;
+
+static void OnSigusr1(int sig) {
+  gotsigusr1 = true;
+}
+
+static void OnSigusr2(int sig) {
+  gotsigusr2 = true;
+}
+
+TEST(fork, childToChild) {
+  if (IsWindows()) return;  // :'(
+  sigset_t mask, oldmask;
+  int ws, parent, child1, child2;
+  gotsigusr1 = false;
+  gotsigusr2 = false;
+  parent = getpid();
+  signal(SIGUSR1, OnSigusr1);
+  signal(SIGUSR2, OnSigusr2);
+  sigemptyset(&mask);
+  sigaddset(&mask, SIGUSR2);
+  sigprocmask(SIG_BLOCK, &mask, &oldmask);
+  ASSERT_NE(-1, (child1 = fork()));
+  if (!child1) {
+    kill(parent, SIGUSR2);
+    sigsuspend(0);
+    _Exit(!gotsigusr1);
+  }
+  sigdelset(&mask, SIGUSR2);
+  sigsuspend(&mask);
+  ASSERT_NE(-1, (child2 = fork()));
+  if (!child2) {
+    kill(child1, SIGUSR1);
+    _Exit(0);
+  }
+  ASSERT_NE(-1, wait(&ws));
+  EXPECT_TRUE(WIFEXITED(ws));
+  EXPECT_EQ(0, WEXITSTATUS(ws));
+  ASSERT_NE(-1, wait(&ws));
+  EXPECT_TRUE(WIFEXITED(ws));
+  EXPECT_EQ(0, WEXITSTATUS(ws));
+  sigprocmask(SIG_SETMASK, &oldmask, 0);
+}
+
 void ForkInSerial(void) {
   int pid, ws;
   ASSERT_NE(-1, (pid = fork()));

test/libc/runtime/getdosargv_test.c

@@ -22,7 +22,7 @@
 
 TEST(GetDosArgv, empty) {
   size_t max = 4;
-  size_t size = ARG_MAX;
+  size_t size = ARG_MAX / 2;
   char *buf = malloc(size * sizeof(char));
   char **argv = malloc(max * sizeof(char *));
   EXPECT_EQ(0, GetDosArgv(u"", buf, size, argv, max));
@@ -33,7 +33,7 @@ TEST(GetDosArgv, empty) {
 
 TEST(GetDosArgv, emptyish) {
   size_t max = 4;
-  size_t size = ARG_MAX;
+  size_t size = ARG_MAX / 2;
   char *buf = malloc(size * sizeof(char));
   char **argv = malloc(max * sizeof(char *));
   EXPECT_EQ(0, GetDosArgv(u"  ", buf, size, argv, max));
@@ -44,7 +44,7 @@ TEST(GetDosArgv, emptyish) {
 
 TEST(GetDosArgv, basicUsage) {
   size_t max = 4;
-  size_t size = ARG_MAX;
+  size_t size = ARG_MAX / 2;
   char *buf = malloc(size * sizeof(char));
   char **argv = malloc(max * sizeof(char *));
   EXPECT_EQ(3, GetDosArgv(u"a\t \"b  c\"  d ", buf, size, argv, max));
@@ -58,7 +58,7 @@ TEST(GetDosArgv, basicUsage) {
 
 TEST(GetDosArgv, advancedUsage) {
   size_t max = 4;
-  size_t size = ARG_MAX;
+  size_t size = ARG_MAX / 2;
   char *buf = malloc(size * sizeof(char));
   char **argv = malloc(max * sizeof(char *));
   EXPECT_EQ(2, GetDosArgv(u"(╯°□°)╯︵ ┻━┻", buf, size, argv, max));
@@ -71,7 +71,7 @@ TEST(GetDosArgv, advancedUsage) {
 
 TEST(GetDosArgv, testAegeanGothicSupplementaryPlanes) {
   size_t max = 4; /* these symbols are almost as old as dos */
-  size_t size = ARG_MAX;
+  size_t size = ARG_MAX / 2;
   char *buf = malloc(size * sizeof(char));
   char **argv = malloc(max * sizeof(char *));
   EXPECT_EQ(2, GetDosArgv(u"𐄷𐄸𐄹𐄺𐄻𐄼 𐌰𐌱𐌲𐌳𐌴𐌵𐌶𐌷", buf, size, argv, max));
@@ -84,7 +84,7 @@ TEST(GetDosArgv, testAegeanGothicSupplementaryPlanes) {
 
 TEST(GetDosArgv, realWorldUsage) {
   size_t max = 512;
-  size_t size = ARG_MAX;
+  size_t size = ARG_MAX / 2;
   char *buf = malloc(size * sizeof(char));
   char **argv = malloc(max * sizeof(char *));
   EXPECT_EQ(5, GetDosArgv(u"C:\\Users\\jtunn\\printargs.com oh yes yes yes",
@@ -145,7 +145,7 @@ TEST(GetDosArgv, quoteInMiddleOfArg_wontSplitArg) {
 
 TEST(GetDosArgv, waqQuoting1) {
   size_t max = 4;
-  size_t size = ARG_MAX;
+  size_t size = ARG_MAX / 2;
   char *buf = malloc(size * sizeof(char));
   char **argv = malloc(max * sizeof(char *));
   EXPECT_EQ(2,
@@ -159,7 +159,7 @@ TEST(GetDosArgv, waqQuoting1) {
 
 TEST(GetDosArgv, waqQuoting2) {
   size_t max = 4;
-  size_t size = ARG_MAX;
+  size_t size = ARG_MAX / 2;
   char *buf = malloc(size * sizeof(char));
   char **argv = malloc(max * sizeof(char *));
   EXPECT_EQ(2, GetDosArgv(u"\"a\\\"b c\" d", buf, size, argv, max));