Perform some code cleanup

libc/calls/read.c

@@ -41,7 +41,6 @@
  * @param size in range [1..0x7ffff000] is reasonable
  * @return [1..size] bytes on success, 0 on EOF, or -1 w/ errno; with
  *     exception of size==0, in which case return zero means no error
- * @see write(), pread(), readv()
  * @asyncsignalsafe
  * @restartable
  * @vforksafe
@@ -49,7 +48,7 @@
 ssize_t read(int fd, void *buf, size_t size) {
   ssize_t rc;
   if (fd >= 0) {
-    if (IsAsan() && !__asan_is_valid(buf, size)) {
+    if ((!buf && size) || (IsAsan() && !__asan_is_valid(buf, size))) {
       rc = efault();
     } else if (fd < g_fds.n && g_fds.p[fd].kind == kFdZip) {
       rc = _weaken(__zipos_read)(
@@ -65,7 +64,7 @@ ssize_t read(int fd, void *buf, size_t size) {
       rc = sys_readv_nt(g_fds.p + fd, &(struct iovec){buf, size}, 1);
     }
   } else {
-    rc = einval();
+    rc = ebadf();
   }
   DATATRACE("read(%d, [%#.*hhs%s], %'zu) → %'zd% m", fd, MAX(0, MIN(40, rc)),
             buf, rc > 40 ? "..." : "", size, rc);

libc/calls/readv.c

@@ -46,8 +46,8 @@
  * @restartable
  */
 ssize_t readv(int fd, const struct iovec *iov, int iovlen) {
-  int i;
   ssize_t rc;
+
   if (fd >= 0 && iovlen >= 0) {
     if (IsAsan() && !__asan_is_valid_iov(iov, iovlen)) {
       rc = efault();
@@ -67,9 +67,12 @@ ssize_t readv(int fd, const struct iovec *iov, int iovlen) {
     } else {
       rc = sys_readv_nt(g_fds.p + fd, iov, iovlen);
     }
+  } else if (fd < 0) {
+    rc = ebadf();
   } else {
     rc = einval();
   }
+
 #if defined(SYSDEBUG) && _DATATRACE
   if (UNLIKELY(__strace > 0)) {
     if (rc == -1 && errno == EFAULT) {
@@ -81,5 +84,6 @@ ssize_t readv(int fd, const struct iovec *iov, int iovlen) {
     }
   }
 #endif
+
   return rc;
 }

libc/calls/setrlimit.c

@@ -18,11 +18,11 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/assert.h"
 #include "libc/calls/calls.h"
-#include "libc/intrin/strace.internal.h"
 #include "libc/calls/struct/rlimit.internal.h"
 #include "libc/dce.h"
 #include "libc/intrin/asan.internal.h"
 #include "libc/intrin/describeflags.internal.h"
+#include "libc/intrin/strace.internal.h"
 #include "libc/sysv/consts/rlimit.h"
 #include "libc/sysv/errfuns.h"
 
@@ -43,6 +43,8 @@
  * - `RLIMIT_FSIZE` causes `SIGXFSZ` to sent to the process when the
  *   soft limit on file size is exceeded and the process is destroyed
  *   when the hard limit is exceeded. It works everywhere but Windows
+ *   and it also causes `EFBIG` to be returned by i/o functions after
+ *   the `SIGXFSZ` signal is delivered or ignored
  *
  * - `RLIMIT_NPROC` limits the number of simultaneous processes and it
  *   should work on all platforms except Windows. Please be advised it

libc/calls/tkill.c

@@ -17,10 +17,10 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
-#include "libc/intrin/strace.internal.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/calls/syscall_support-nt.internal.h"
 #include "libc/dce.h"
+#include "libc/intrin/strace.internal.h"
 #include "libc/nt/enum/threadaccess.h"
 #include "libc/nt/runtime.h"
 #include "libc/nt/thread.h"
@@ -48,6 +48,7 @@ static textwindows int sys_tkill_nt(int tid, int sig) {
  * @param tid is thread id
  * @param sig does nothing on xnu
  * @return 0 on success, or -1 w/ errno
+ * @asyncsignalsafe
  */
 int tkill(int tid, int sig) {
   int rc;

libc/calls/write.c

@@ -34,12 +34,27 @@
  * This function changes the current file position. For documentation
  * on file position behaviors and gotchas, see the lseek() function.
  *
- * @param fd is something open()'d earlier
+ * @param fd is open file descriptor
  * @param buf is copied from, cf. copy_file_range(), sendfile(), etc.
- * @param size in range [1..0x7ffff000] is reasonable
  * @return [1..size] bytes on success, or -1 w/ errno; noting zero is
  *     impossible unless size was passed as zero to do an error check
- * @see read(), pwrite(), writev(), SIGPIPE
+ * @raise EBADF if `fd` is negative or not an open file descriptor
+ * @raise EBADF if `fd` wasn't opened with `O_WRONLY` or `O_RDWR`
+ * @raise EPIPE if `fd` is a pipe whose other reader end was closed,
+ *     after the `SIGPIPE` signal was delivered, blocked, or ignored
+ * @raise EFBIG if `RLIMIT_FSIZE` soft limit was exceeded, after the
+ *     `SIGXFSZ` signal was either delivered, blocked, or ignored
+ * @raise EFAULT if `size` is nonzero and `buf` points to bad memory
+ * @raise EPERM if pledge() is in play without the stdio promise
+ * @raise ENOSPC if device containing `fd` is full
+ * @raise EIO if low-level i/o error happened
+ * @raise EINTR if signal was delivered instead
+ * @raise EAGAIN if `O_NONBLOCK` is in play and write needs to block
+ * @raise ENOBUFS if kernel lacked internal resources; which FreeBSD
+ *     and XNU say could happen with sockets, and OpenBSD documents it
+ *     as a general possibility; whereas other system don't specify it
+ * @raise ENXIO is specified only by POSIX and XNU when a request is
+ *     made of a nonexistent device or outside device capabilities
  * @asyncsignalsafe
  * @restartable
  * @vforksafe
@@ -47,7 +62,7 @@
 ssize_t write(int fd, const void *buf, size_t size) {
   ssize_t rc;
   if (fd >= 0) {
-    if (IsAsan() && !__asan_is_valid(buf, size)) {
+    if ((!buf && size) || (IsAsan() && !__asan_is_valid(buf, size))) {
       rc = efault();
     } else if (fd < g_fds.n && g_fds.p[fd].kind == kFdZip) {
       rc = _weaken(__zipos_write)(
@@ -63,7 +78,7 @@ ssize_t write(int fd, const void *buf, size_t size) {
       rc = sys_writev_nt(fd, &(struct iovec){buf, size}, 1);
     }
   } else {
-    rc = einval();
+    rc = ebadf();
   }
   DATATRACE("write(%d, %#.*hhs%s, %'zu) → %'zd% m", fd, MAX(0, MIN(40, rc)),
             buf, rc > 40 ? "..." : "", size, rc);

libc/calls/writev.c

@@ -50,7 +50,6 @@
  * @restartable
  */
 ssize_t writev(int fd, const struct iovec *iov, int iovlen) {
-  int i;
   ssize_t rc;
 
   if (fd >= 0 && iovlen >= 0) {
@@ -72,6 +71,8 @@ ssize_t writev(int fd, const struct iovec *iov, int iovlen) {
     } else {
       rc = sys_writev_nt(fd, iov, iovlen);
     }
+  } else if (fd < 0) {
+    rc = ebadf();
   } else {
     rc = einval();
   }

libc/runtime/clone.c

@@ -488,13 +488,11 @@ static int CloneLinux(int (*func)(void *arg, int tid), char *stk, size_t stksz,
 // COSMOPOLITAN
 
 /**
- * Creates thread without malloc being linked, e.g.
+ * Creates thread without malloc being linked.
  *
- *     int worker(void *arg) {
+ * If you use clone() you're on you're own, e.g.
- *       return 0;
- *     }
  *
- *     // NOTE: See _mktls() for _Thread_local support.
+ *     int worker(void *arg) { return 0; }
  *     struct CosmoTib tib = {.tib_self = &tib, .tib_tid = -1};
  *     char *stk = _mapstack();
  *     tid = clone(worker, stk, GetStackSize() - 16,

libc/thread/wait0.c

@@ -100,4 +100,7 @@ void _wait0(const atomic_int *ctid) {
       _wait0_poll(&ts);
     }
   }
+  if (IsOpenbsd()) {
+    sched_yield();  // TODO(jart): whhhy?
+  }
 }

net/http/ip.h

@@ -39,6 +39,7 @@ bool IsMulticastIp(uint32_t);
 bool IsAnonymousIp(uint32_t);
 int CategorizeIp(uint32_t);
 const char *GetIpCategoryName(int);
+bool IsCloudflareIp(uint32_t);
 
 COSMOPOLITAN_C_END_
 #endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */

net/http/iscloudflare.c

@@ -0,0 +1,42 @@
+/*-*- 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 "net/http/ip.h"
+
+/**
+ * Returns true if `x` is Cloudflare IPv4 address.
+ *
+ * @see https://www.cloudflare.com/ips/ (April 8, 2021)
+ */
+bool IsCloudflareIp(uint32_t x) {
+  return (x & 0xfffffc00) == 0x6715f400 ||  // 103.21.244.0/22
+         (x & 0xfffffc00) == 0x6716c800 ||  // 103.22.200.0/22
+         (x & 0xfffffc00) == 0x671f0400 ||  // 103.31.4.0/22
+         (x & 0xfff80000) == 0x68100000 ||  // 104.16.0.0/13
+         (x & 0xfffc0000) == 0x68180000 ||  // 104.24.0.0/14
+         (x & 0xffffc000) == 0x6ca2c000 ||  // 108.162.192.0/18
+         (x & 0xfffffc00) == 0x83004800 ||  // 131.0.72.0/22
+         (x & 0xffffc000) == 0x8d654000 ||  // 141.101.64.0/18
+         (x & 0xfffe0000) == 0xa29e0000 ||  // 162.158.0.0/15
+         (x & 0xfff80000) == 0xac400000 ||  // 172.64.0.0/13
+         (x & 0xfffff000) == 0xadf53000 ||  // 173.245.48.0/20
+         (x & 0xfffff000) == 0xbc726000 ||  // 188.114.96.0/20
+         (x & 0xfffff000) == 0xbe5df000 ||  // 190.93.240.0/20
+         (x & 0xfffffc00) == 0xc5eaf000 ||  // 197.234.240.0/22
+         (x & 0xffff8000) == 0xc6298000;    // 198.41.128.0/17
+}

test/libc/calls/write_test.c

@@ -20,13 +20,81 @@
 #include "libc/calls/internal.h"
 #include "libc/calls/struct/iovec.h"
 #include "libc/calls/struct/iovec.internal.h"
+#include "libc/calls/struct/rlimit.h"
+#include "libc/calls/struct/sigaction.h"
+#include "libc/calls/struct/sigset.h"
 #include "libc/calls/syscall-sysv.internal.h"
+#include "libc/dce.h"
+#include "libc/errno.h"
 #include "libc/sock/internal.h"
 #include "libc/sysv/consts/nr.h"
 #include "libc/sysv/consts/o.h"
+#include "libc/sysv/consts/rlimit.h"
+#include "libc/sysv/consts/sig.h"
 #include "libc/testlib/ezbench.h"
+#include "libc/testlib/subprocess.h"
 #include "libc/testlib/testlib.h"
 
+char testlib_enable_tmp_setup_teardown;
+
+TEST(write, notOpen_ebadf) {
+  ASSERT_SYS(EBADF, -1, write(-1, 0, 0));
+  ASSERT_SYS(EBADF, -1, write(+3, 0, 0));
+}
+
+TEST(write, readOnlyFd_ebadf) {
+  ASSERT_SYS(0, 0, touch("foo", 0644));
+  ASSERT_SYS(0, 3, open("foo", O_RDONLY));
+  ASSERT_SYS(EBADF, -1, write(3, "x", 1));
+  ASSERT_SYS(0, 0, close(3));
+}
+
+TEST(write, badMemory_efault) {
+  ASSERT_SYS(EFAULT, -1, write(1, 0, 1));
+  if (!IsAsan()) return;
+  ASSERT_SYS(EFAULT, -1, write(1, (void *)1, 1));
+}
+
+TEST(write, brokenPipe_sigpipeIgnored_returnsEpipe) {
+  int fds[2];
+  SPAWN(fork);
+  signal(SIGPIPE, SIG_IGN);
+  ASSERT_SYS(0, 0, pipe(fds));
+  ASSERT_SYS(0, 1, write(4, "x", 1));
+  ASSERT_SYS(0, 0, close(3));
+  ASSERT_SYS(EPIPE, -1, write(4, "x", 1));
+  ASSERT_SYS(0, 0, close(4));
+  EXITS(0);
+}
+
+TEST(write, brokenPipe_sigpipeBlocked_returnsEpipe) {
+  int fds[2];
+  sigset_t mask;
+  SPAWN(fork);
+  signal(SIGPIPE, SIG_DFL);
+  sigemptyset(&mask);
+  sigaddset(&mask, SIGPIPE);
+  sigprocmask(SIG_BLOCK, &mask, 0);
+  ASSERT_SYS(0, 0, pipe(fds));
+  ASSERT_SYS(0, 0, close(3));
+  ASSERT_SYS(EPIPE, -1, write(4, "x", 1));
+  ASSERT_SYS(0, 0, close(4));
+  EXITS(0);
+}
+
+TEST(write, rlimitFsizeExceeded_raisesEfbig) {
+  if (IsWindows()) return;  // not supported
+  struct rlimit rl = {1, 10};
+  SPAWN(fork);
+  signal(SIGXFSZ, SIG_IGN);
+  ASSERT_SYS(0, 0, setrlimit(RLIMIT_FSIZE, &rl));
+  ASSERT_SYS(0, 3, creat("foo", 0644));
+  ASSERT_SYS(0, 1, write(3, "x", 1));
+  ASSERT_SYS(EFBIG, -1, write(3, "x", 1));
+  ASSERT_SYS(0, 0, close(3));
+  EXITS(0);
+}
+
 static long Write(long fd, const void *data, unsigned long size) {
   long ax, di, si, dx;
   asm volatile("syscall"

test/libc/calls/writev_test.c

@@ -20,12 +20,15 @@
 #include "libc/calls/struct/iovec.h"
 #include "libc/dce.h"
 #include "libc/errno.h"
+#include "libc/limits.h"
 #include "libc/macros.internal.h"
-#include "libc/mem/mem.h"
+#include "libc/mem/gc.h"
 #include "libc/mem/gc.internal.h"
+#include "libc/mem/mem.h"
 #include "libc/runtime/runtime.h"
 #include "libc/sock/sock.h"
 #include "libc/sysv/consts/auxv.h"
+#include "libc/sysv/consts/iov.h"
 #include "libc/sysv/consts/o.h"
 #include "libc/testlib/testlib.h"
 
@@ -35,6 +38,32 @@ void SetUpOnce(void) {
   ASSERT_SYS(0, 0, pledge("stdio rpath wpath cpath fattr", 0));
 }
 
+TEST(writev, negativeFd_ebadf) {
+  ASSERT_SYS(EBADF, -1, writev(-1, 0, 0));
+}
+
+TEST(writev, negativeCount_einval) {
+  ASSERT_SYS(EINVAL, -1, writev(1, 0, -1));
+}
+
+TEST(writev, negative_einvalOrEfault) {
+  struct iovec v[] = {{"", -1}};
+  ASSERT_EQ(-1, writev(1, v, 1));
+  ASSERT_TRUE(errno == EINVAL || errno == EFAULT);
+  errno = 0;
+}
+
+TEST(writev, exceedsIovMax_einval) {
+  if (IsWindows()) return;  // it's complicated
+  int i, n = IOV_MAX + 1;
+  struct iovec *v = _gc(malloc(sizeof(struct iovec) * n));
+  for (i = 0; i < n; ++i) {
+    v[i].iov_base = "x";
+    v[i].iov_len = 1;
+  }
+  ASSERT_SYS(EINVAL, -1, writev(1, v, n));
+}
+
 TEST(writev, test) {
   int fd;
   char ba[1] = "a";

test/libc/thread/pthread_barrier_wait_test.c

@@ -20,8 +20,8 @@
 #include "libc/atomic.h"
 #include "libc/errno.h"
 #include "libc/intrin/atomic.h"
-#include "libc/mem/mem.h"
 #include "libc/mem/gc.internal.h"
+#include "libc/mem/mem.h"
 #include "libc/testlib/testlib.h"
 #include "libc/thread/spawn.h"
 #include "libc/thread/thread.h"