// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

#include "platform/globals.h"
#if defined(DART_HOST_OS_MACOS)

#include "bin/socket_base.h"

#include <errno.h>        // NOLINT
#include <ifaddrs.h>      // NOLINT
#include <net/if.h>       // NOLINT
#include <netinet/tcp.h>  // NOLINT
#include <stdio.h>        // NOLINT
#include <stdlib.h>       // NOLINT
#include <string.h>       // NOLINT
#include <sys/stat.h>     // NOLINT
#include <unistd.h>       // NOLINT

#include "bin/fdutils.h"
#include "bin/file.h"
#include "bin/socket_base_macos.h"
#include "platform/signal_blocker.h"

namespace dart {
namespace bin {

void SocketBase::GetError(intptr_t fd, OSError* os_error) {
  int len = sizeof(errno);
  getsockopt(fd, SOL_SOCKET, SO_ERROR, &errno,
             reinterpret_cast<socklen_t*>(&len));
  os_error->SetCodeAndMessage(OSError::kSystem, errno);
}

int SocketBase::GetType(intptr_t fd) {
  struct stat buf;
  int result = fstat(fd, &buf);
  if (result == -1) {
    return -1;
  }
  if (S_ISCHR(buf.st_mode)) {
    return File::kTerminal;
  }
  if (S_ISFIFO(buf.st_mode)) {
    return File::kPipe;
  }
  if (S_ISREG(buf.st_mode)) {
    return File::kFile;
  }
  return File::kOther;
}

AddressList<SocketAddress>* SocketBase::LookupAddress(const char* host,
                                                      int type,
                                                      OSError** os_error) {
  // Perform a name lookup for a host name.
  struct addrinfo hints;
  memset(&hints, 0, sizeof(hints));
  hints.ai_family = SocketAddress::FromType(type);
  hints.ai_socktype = SOCK_STREAM;
  hints.ai_flags = 0;
  hints.ai_protocol = IPPROTO_TCP;

  // Check if host is valid dotted-quad IPv4 address or valid IPv6 address.
  struct in_addr ipv4_bin;
  struct in6_addr ipv6_bin;
  if (inet_pton(AF_INET, host, &ipv4_bin) == 1
#ifdef INET_PTON_FLAWED
      // MacOS accepts `0177.0.0.1` as IPv4.
      // Reject leading zero digits that could be intended as octal.
      && SocketBase::IsIPv4WithoutLeadingZeros(host)
#endif
  ) {
    // If it is a valid strict IPv4, parse it safely as a numeric host.
    hints.ai_family = AF_INET;
    hints.ai_flags |= AI_NUMERICHOST;  // Safe local parsing
  } else if (inet_pton(AF_INET6, host, &ipv6_bin) == 1) {
    // 2. If it is a valid strict IPv6, parse it safely as a numeric host.
    hints.ai_family = AF_INET6;
    hints.ai_flags |= AI_NUMERICHOST;  // Safe local parsing
  } else if (inet_aton(host, &ipv4_bin) != 0) {
    // Reject legacy inet_aton strings (like "127.1", "0x7f.1")
    // If inet_aton accepts and inet_pton does not, it's a malformed IP.
    ASSERT(*os_error == nullptr);
    int status = EAI_NONAME;
    *os_error =
        new OSError(status, gai_strerror(status), OSError::kGetAddressInfo);
    return nullptr;
  }

  struct addrinfo* info = nullptr;
  int status = getaddrinfo(host, nullptr, &hints, &info);
  if (status != 0) {
    ASSERT(*os_error == nullptr);
    *os_error =
        new OSError(status, gai_strerror(status), OSError::kGetAddressInfo);
    return nullptr;
  }
  intptr_t count = 0;
  for (struct addrinfo* c = info; c != nullptr; c = c->ai_next) {
    if ((c->ai_family == AF_INET) || (c->ai_family == AF_INET6)) {
      count++;
    }
  }
  intptr_t i = 0;
  AddressList<SocketAddress>* addresses = new AddressList<SocketAddress>(count);
  for (struct addrinfo* c = info; c != nullptr; c = c->ai_next) {
    if ((c->ai_family == AF_INET) || (c->ai_family == AF_INET6)) {
      addresses->SetAt(i, new SocketAddress(RawAddr::FromInet4or6(c->ai_addr)));
      i++;
    }
  }
  freeaddrinfo(info);
  return addresses;
}

bool SocketBase::SetMulticastLoop(intptr_t fd,
                                  intptr_t protocol,
                                  bool enabled) {
  u_int on = enabled ? 1 : 0;
  int level = protocol == SocketAddress::TYPE_IPV4 ? IPPROTO_IP : IPPROTO_IPV6;
  int optname = protocol == SocketAddress::TYPE_IPV4 ? IP_MULTICAST_LOOP
                                                     : IPV6_MULTICAST_LOOP;
  return NO_RETRY_EXPECTED(setsockopt(
             fd, level, optname, reinterpret_cast<char*>(&on), sizeof(on))) ==
         0;
}

bool SocketBase::GetOption(intptr_t fd,
                           int level,
                           int option,
                           char* data,
                           unsigned int* length) {
  return NO_RETRY_EXPECTED(getsockopt(fd, level, option, data, length)) == 0;
}

static bool JoinOrLeaveMulticast(intptr_t fd,
                                 const RawAddr& addr,
                                 const RawAddr& interface,
                                 int interfaceIndex,
                                 bool join) {
  if (addr.addr.sa_family == AF_INET) {
    ASSERT(interface.addr.sa_family == AF_INET);
    struct ip_mreq mreq;
    memmove(&mreq.imr_multiaddr, &addr.in.sin_addr,
            SocketAddress::GetInAddrLength(addr));
    memmove(&mreq.imr_interface, &interface.in.sin_addr,
            SocketAddress::GetInAddrLength(interface));
    if (join) {
      return NO_RETRY_EXPECTED(setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
                                          &mreq, sizeof(mreq))) == 0;
    } else {
      return NO_RETRY_EXPECTED(setsockopt(fd, IPPROTO_IP, IP_DROP_MEMBERSHIP,
                                          &mreq, sizeof(mreq))) == 0;
    }
  } else {
    ASSERT(addr.addr.sa_family == AF_INET6);
    struct ipv6_mreq mreq;
    memmove(&mreq.ipv6mr_multiaddr, &addr.in6.sin6_addr,
            SocketAddress::GetInAddrLength(addr));
    mreq.ipv6mr_interface = interfaceIndex;
    if (join) {
      return NO_RETRY_EXPECTED(setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP,
                                          &mreq, sizeof(mreq))) == 0;
    } else {
      return NO_RETRY_EXPECTED(setsockopt(fd, IPPROTO_IPV6, IPV6_LEAVE_GROUP,
                                          &mreq, sizeof(mreq))) == 0;
    }
  }
}

bool SocketBase::JoinMulticast(intptr_t fd,
                               const RawAddr& addr,
                               const RawAddr& interface,
                               int interfaceIndex) {
  return JoinOrLeaveMulticast(fd, addr, interface, interfaceIndex, true);
}

bool SocketBase::LeaveMulticast(intptr_t fd,
                                const RawAddr& addr,
                                const RawAddr& interface,
                                int interfaceIndex) {
  return JoinOrLeaveMulticast(fd, addr, interface, interfaceIndex, false);
}

}  // namespace bin
}  // namespace dart

#endif  // defined(DART_HOST_OS_MACOS)