text: /* crypto/bio/bss_sock.c */
  /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   * All rights reserved.
   *
   * This package is an SSL implementation written
   * by Eric Young (eay@cryptsoft.com).
   * The implementation was written so as to conform with Netscapes SSL.
   *
   * This library is free for commercial and non-commercial use as long as
   * the following conditions are aheared to.  The following conditions
   * apply to all code found in this distribution, be it the RC4, RSA,
   * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
   * included with this distribution is covered by the same copyright terms
   * except that the holder is Tim Hudson (tjh@cryptsoft.com).
   *
   * Copyright remains Eric Young's, and as such any Copyright notices in
   * the code are not to be removed.
   * If this package is used in a product, Eric Young should be given attribution
   * as the author of the parts of the library used.
   * This can be in the form of a textual message at program startup or
   * in documentation (online or textual) provided with the package.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. All advertising materials mentioning features or use of this software
   *    must display the following acknowledgement:
   *    "This product includes cryptographic software written by
   *     Eric Young (eay@cryptsoft.com)"
   *    The word 'cryptographic' can be left out if the rouines from the library
   *    being used are not cryptographic related :-).
   * 4. If you include any Windows specific code (or a derivative thereof) from
   *    the apps directory (application code) you must include an acknowledgement:
   *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
   *
   * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   * The licence and distribution terms for any publically available version or
   * derivative of this code cannot be changed.  i.e. this code cannot simply be
   * copied and put under another distribution licence
   * [including the GNU Public Licence.] */
  
  #include <openssl/bio.h>
  
  #if !defined(OPENSSL_TRUSTY)
  
  #include <fcntl.h>
  #include <string.h>
  
  #if !defined(OPENSSL_WINDOWS)
  #include <unistd.h>
  #else
  OPENSSL_MSVC_PRAGMA(warning(push, 3))
  #include <winsock2.h>
  OPENSSL_MSVC_PRAGMA(warning(pop))
  #endif
  
  #include "internal.h"
  
  
  #if !defined(OPENSSL_WINDOWS)
  static int closesocket(int sock) {
    return close(sock);
  }
  #endif
  
  static int sock_new(BIO *bio) {
    bio->init = 0;
    bio->num = 0;
    bio->ptr = NULL;
    bio->flags = 0;
    return 1;
  }
  
  static int sock_free(BIO *bio) {
    if (bio == NULL) {
      return 0;
    }
  
    if (bio->shutdown) {
      if (bio->init) {
        closesocket(bio->num);
      }
      bio->init = 0;
      bio->flags = 0;
    }
    return 1;
  }
  
  static int sock_read(BIO *b, char *out, int outl) {
    int ret = 0;
  
    if (out == NULL) {
      return 0;
    }
  
    bio_clear_socket_error();
  #if defined(OPENSSL_WINDOWS)
    ret = recv(b->num, out, outl, 0);
  #else
    ret = read(b->num, out, outl);
  #endif
    BIO_clear_retry_flags(b);
    if (ret <= 0) {
      if (bio_fd_should_retry(ret)) {
        BIO_set_retry_read(b);
      }
    }
    return ret;
  }
  
  static int sock_write(BIO *b, const char *in, int inl) {
    int ret;
  
    bio_clear_socket_error();
  #if defined(OPENSSL_WINDOWS)
    ret = send(b->num, in, inl, 0);
  #else
    ret = write(b->num, in, inl);
  #endif
    BIO_clear_retry_flags(b);
    if (ret <= 0) {
      if (bio_fd_should_retry(ret)) {
        BIO_set_retry_write(b);
      }
    }
    return ret;
  }
  
  static long sock_ctrl(BIO *b, int cmd, long num, void *ptr) {
    long ret = 1;
    int *ip;
  
    switch (cmd) {
      case BIO_C_SET_FD:
        sock_free(b);
        b->num = *((int *)ptr);
        b->shutdown = (int)num;
        b->init = 1;
        break;
      case BIO_C_GET_FD:
        if (b->init) {
          ip = (int *)ptr;
          if (ip != NULL) {
            *ip = b->num;
          }
          ret = b->num;
        } else {
          ret = -1;
        }
        break;
      case BIO_CTRL_GET_CLOSE:
        ret = b->shutdown;
        break;
      case BIO_CTRL_SET_CLOSE:
        b->shutdown = (int)num;
        break;
      case BIO_CTRL_FLUSH:
        ret = 1;
        break;
      default:
        ret = 0;
        break;
    }
    return ret;
  }
  
  static const BIO_METHOD methods_sockp = {
      BIO_TYPE_SOCKET, "socket",
      sock_write,      sock_read,
      NULL /* puts */, NULL /* gets, */,
      sock_ctrl,       sock_new,
      sock_free,       NULL /* callback_ctrl */,
  };
  
  const BIO_METHOD *BIO_s_socket(void) { return &methods_sockp; }
  
  BIO *BIO_new_socket(int fd, int close_flag) {
    BIO *ret;
  
    ret = BIO_new(BIO_s_socket());
    if (ret == NULL) {
      return NULL;
    }
    BIO_set_fd(ret, fd, close_flag);
    return ret;
  }
  
  #endif  // OPENSSL_TRUSTY
  