/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-â
âvi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :viâ
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â Copyright 2020 Justine Alexandra Roberts Tunney                              â
â                                                                              â
â Permission to use, copy, modify, and/or distribute this software for         â
â any purpose with or without fee is hereby granted, provided that the         â
â above copyright notice and this permission notice appear in all copies.      â
â                                                                              â
â THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                â
â WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                â
â WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             â
â AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         â
â DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        â
â PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               â
â TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             â
â PERFORMANCE OF THIS SOFTWARE.                                                â
ââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââââ*/
#include "libc/calls/cp.internal.h"
#include "libc/calls/internal.h"
#include "libc/calls/struct/iovec.h"
#include "libc/calls/struct/iovec.internal.h"
#include "libc/dce.h"
#include "libc/intrin/asan.internal.h"
#include "libc/intrin/strace.internal.h"
#include "libc/macros.internal.h"
#include "libc/sock/internal.h"
#include "libc/sock/sock.h"
#include "libc/sysv/errfuns.h"

/**
 * Sends data to network socket.
 *
 * @param fd is the file descriptor returned by socket()
 * @param buf is the data to send, which we'll copy if necessary
 * @param size is the byte-length of buf
 * @param flags MSG_OOB, MSG_DONTROUTE, MSG_PARTIAL, MSG_NOSIGNAL, etc.
 * @return number of bytes transmitted, or -1 w/ errno
 * @error EINTR, EHOSTUNREACH, ECONNRESET (UDP ICMP Port Unreachable),
 *     EPIPE (if MSG_NOSIGNAL), EMSGSIZE, ENOTSOCK, EFAULT, etc.
 * @cancellationpoint
 * @asyncsignalsafe
 * @restartable (unless SO_RCVTIMEO)
 */
ssize_t send(int fd, const void *buf, size_t size, int flags) {
  ssize_t rc;
  BEGIN_CANCELLATION_POINT;

  if (IsAsan() && !__asan_is_valid(buf, size)) {
    rc = efault();
  } else if (!IsWindows()) {
    rc = sys_sendto(fd, buf, size, flags, 0, 0);
  } else if (__isfdopen(fd)) {
    if (__isfdkind(fd, kFdSocket)) {
      rc = sys_send_nt(fd, (struct iovec[]){{buf, size}}, 1, flags);
    } else if (__isfdkind(fd, kFdFile)) {
      if (flags) {
        rc = einval();
      } else {
        rc = sys_write_nt(fd, (struct iovec[]){{buf, size}}, 1, -1);
      }
    } else {
      rc = enotsock();
    }
  } else {
    rc = ebadf();
  }

  END_CANCELLATION_POINT;
  DATATRACE("send(%d, %#.*hhs%s, %'zu, %#x) â %'ld% lm", fd,
            MAX(0, MIN(40, rc)), buf, rc > 40 ? "..." : "", size, flags, rc);
  return rc;
}
