text: // Copyright (c) 2016, 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(HOST_OS_FUCHSIA)
  
  #include "bin/socket_base.h"
  
  #include <errno.h>
  #include <ifaddrs.h>
  #include <net/if.h>
  #include <netinet/tcp.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <sys/stat.h>
  #include <unistd.h>
  #include <vector>
  
  #include "bin/eventhandler.h"
  #include "bin/fdutils.h"
  #include "bin/file.h"
  #include "bin/socket_base_fuchsia.h"
  #include "platform/signal_blocker.h"
  
  // #define SOCKET_LOG_INFO 1
  // #define SOCKET_LOG_ERROR 1
  
  // define SOCKET_LOG_ERROR to get log messages only for errors.
  // define SOCKET_LOG_INFO to get log messages for both information and errors.
  #if defined(SOCKET_LOG_INFO) || defined(SOCKET_LOG_ERROR)
  #define LOG_ERR(msg, ...)                                                      \
    {                                                                            \
      int err = errno;                                                           \
      Syslog::PrintErr("Dart Socket ERROR: %s:%d: " msg, __FILE__, __LINE__,     \
                       ##__VA_ARGS__);                                           \
      errno = err;                                                               \
    }
  #if defined(SOCKET_LOG_INFO)
  #define LOG_INFO(msg, ...)                                                     \
    Syslog::Print("Dart Socket INFO: %s:%d: " msg, __FILE__, __LINE__,           \
                  ##__VA_ARGS__)
  #else
  #define LOG_INFO(msg, ...)
  #endif  // defined(SOCKET_LOG_INFO)
  #else
  #define LOG_ERR(msg, ...)
  #define LOG_INFO(msg, ...)
  #endif  // defined(SOCKET_LOG_INFO) || defined(SOCKET_LOG_ERROR)
  
  namespace dart {
  namespace bin {
  
  SocketAddress::SocketAddress(struct sockaddr* sa, bool unnamed_unix_socket) {
    // Fuchsia does not support unix domain sockets.
    if (unnamed_unix_socket) {
      FATAL("Fuchsia does not support unix domain sockets.");
    }
    ASSERT(INET6_ADDRSTRLEN >= INET_ADDRSTRLEN);
    if (!SocketBase::FormatNumericAddress(*reinterpret_cast<RawAddr*>(sa),
                                          as_string_, INET6_ADDRSTRLEN)) {
      as_string_[0] = 0;
    }
    socklen_t salen = GetAddrLength(*reinterpret_cast<RawAddr*>(sa));
    memmove(reinterpret_cast<void*>(&addr_), sa, salen);
  }
  
  
  bool SocketBase::Initialize() {
    // Nothing to do on Fuchsia.
    return true;
  }
  
  bool SocketBase::FormatNumericAddress(const RawAddr& addr,
                                        char* address,
                                        int len) {
    socklen_t salen = SocketAddress::GetAddrLength(addr);
    LOG_INFO("SocketBase::FormatNumericAddress: calling getnameinfo\n");
    return (NO_RETRY_EXPECTED(getnameinfo(&addr.addr, salen, address, len, NULL,
                                          0, NI_NUMERICHOST) == 0));
  }
  
  bool SocketBase::IsBindError(intptr_t error_number) {
    return error_number == EADDRINUSE || error_number == EADDRNOTAVAIL ||
           error_number == EINVAL;
  }
  
  intptr_t SocketBase::Available(intptr_t fd) {
    IOHandle* handle = reinterpret_cast<IOHandle*>(fd);
    return handle->AvailableBytes();
  }
  
  intptr_t SocketBase::Read(intptr_t fd,
                            void* buffer,
                            intptr_t num_bytes,
                            SocketOpKind sync) {
    IOHandle* handle = reinterpret_cast<IOHandle*>(fd);
    ASSERT(handle->fd() >= 0);
    LOG_INFO("SocketBase::Read: calling read(%ld, %p, %ld)\n", handle->fd(),
             buffer, num_bytes);
    intptr_t read_bytes = handle->Read(buffer, num_bytes);
    ASSERT(EAGAIN == EWOULDBLOCK);
    if ((sync == kAsync) && (read_bytes == -1) && (errno == EWOULDBLOCK)) {
      // If the read would block we need to retry and therefore return 0
      // as the number of bytes written.
      read_bytes = 0;
    } else if (read_bytes == -1) {
      LOG_ERR("SocketBase::Read: read(%ld, %p, %ld) failed\n", handle->fd(),
              buffer, num_bytes);
    } else {
      LOG_INFO("SocketBase::Read: read(%ld, %p, %ld) succeeded\n", handle->fd(),
               buffer, num_bytes);
    }
    return read_bytes;
  }
  
  intptr_t SocketBase::RecvFrom(intptr_t fd,
                                void* buffer,
                                intptr_t num_bytes,
                                RawAddr* addr,
                                SocketOpKind sync) {
    errno = ENOSYS;
    return -1;
  }
  
  bool SocketBase::AvailableDatagram(intptr_t fd,
                                     void* buffer,
                                     intptr_t num_bytes) {
    return false;
  }
  
  intptr_t SocketBase::Write(intptr_t fd,
                             const void* buffer,
                             intptr_t num_bytes,
                             SocketOpKind sync) {
    IOHandle* handle = reinterpret_cast<IOHandle*>(fd);
    ASSERT(handle->fd() >= 0);
    LOG_INFO("SocketBase::Write: calling write(%ld, %p, %ld)\n", handle->fd(),
             buffer, num_bytes);
    intptr_t written_bytes = handle->Write(buffer, num_bytes);
    ASSERT(EAGAIN == EWOULDBLOCK);
    if ((sync == kAsync) && (written_bytes == -1) && (errno == EWOULDBLOCK)) {
      // If the would block we need to retry and therefore return 0 as
      // the number of bytes written.
      written_bytes = 0;
    } else if (written_bytes == -1) {
      LOG_ERR("SocketBase::Write: write(%ld, %p, %ld) failed\n", handle->fd(),
              buffer, num_bytes);
    } else {
      LOG_INFO("SocketBase::Write: write(%ld, %p, %ld) succeeded\n", handle->fd(),
               buffer, num_bytes);
    }
    return written_bytes;
  }
  
  intptr_t SocketBase::SendTo(intptr_t fd,
                              const void* buffer,
                              intptr_t num_bytes,
                              const RawAddr& addr,
                              SocketOpKind sync) {
    errno = ENOSYS;
    return -1;
  }
  
  intptr_t SocketBase::GetPort(intptr_t fd) {
    IOHandle* handle = reinterpret_cast<IOHandle*>(fd);
    ASSERT(handle->fd() >= 0);
    RawAddr raw;
    socklen_t size = sizeof(raw);
    LOG_INFO("SocketBase::GetPort: calling getsockname(%ld)\n", handle->fd());
    if (NO_RETRY_EXPECTED(getsockname(handle->fd(), &raw.addr, &size))) {
      return 0;
    }
    return SocketAddress::GetAddrPort(raw);
  }
  
  SocketAddress* SocketBase::GetRemotePeer(intptr_t fd, intptr_t* port) {
    IOHandle* handle = reinterpret_cast<IOHandle*>(fd);
    ASSERT(handle->fd() >= 0);
    RawAddr raw;
    socklen_t size = sizeof(raw);
    if (NO_RETRY_EXPECTED(getpeername(handle->fd(), &raw.addr, &size))) {
      return NULL;
    }
    *port = SocketAddress::GetAddrPort(raw);
    return new SocketAddress(&raw.addr);
  }
  
  void SocketBase::GetError(intptr_t fd, OSError* os_error) {
    IOHandle* handle = reinterpret_cast<IOHandle*>(fd);
    ASSERT(handle->fd() >= 0);
    int len = sizeof(errno);
    int err = 0;
    VOID_NO_RETRY_EXPECTED(getsockopt(handle->fd(), SOL_SOCKET, SO_ERROR, &err,
                                      reinterpret_cast<socklen_t*>(&len)));
    errno = err;
    os_error->SetCodeAndMessage(OSError::kSystem, errno);
  }
  
  int SocketBase::GetType(intptr_t fd) {
    errno = ENOSYS;
    return -1;
  }
  
  intptr_t SocketBase::GetStdioHandle(intptr_t num) {
    return num;
  }
  
  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 = AI_ADDRCONFIG;
    hints.ai_protocol = IPPROTO_TCP;
    struct addrinfo* info = NULL;
    LOG_INFO("SocketBase::LookupAddress: calling getaddrinfo\n");
    int status = NO_RETRY_EXPECTED(getaddrinfo(host, 0, &hints, &info));
    if (status != 0) {
      // We failed, try without AI_ADDRCONFIG. This can happen when looking up
      // e.g. '::1', when there are no global IPv6 addresses.
      hints.ai_flags = 0;
      LOG_INFO("SocketBase::LookupAddress: calling getaddrinfo again\n");
      status = NO_RETRY_EXPECTED(getaddrinfo(host, 0, &hints, &info));
      if (status != 0) {
        ASSERT(*os_error == NULL);
        *os_error =
            new OSError(status, gai_strerror(status), OSError::kGetAddressInfo);
        return NULL;
      }
    }
    intptr_t count = 0;
    for (struct addrinfo* c = info; c != NULL; 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 != NULL; c = c->ai_next) {
      if ((c->ai_family == AF_INET) || (c->ai_family == AF_INET6)) {
        addresses->SetAt(i, new SocketAddress(c->ai_addr));
        i++;
      }
    }
    freeaddrinfo(info);
    return addresses;
  }
  
  bool SocketBase::ReverseLookup(const RawAddr& addr,
                                 char* host,
                                 intptr_t host_len,
                                 OSError** os_error) {
    errno = ENOSYS;
    return false;
  }
  
  bool SocketBase::ParseAddress(int type, const char* address, RawAddr* addr) {
    int result;
    if (type == SocketAddress::TYPE_IPV4) {
      result = NO_RETRY_EXPECTED(inet_pton(AF_INET, address, &addr->in.sin_addr));
    } else {
      ASSERT(type == SocketAddress::TYPE_IPV6);
      result =
          NO_RETRY_EXPECTED(inet_pton(AF_INET6, address, &addr->in6.sin6_addr));
    }
    return (result == 1);
  }
  
  bool SocketBase::RawAddrToString(RawAddr* addr, char* str) {
    if (addr->addr.sa_family == AF_INET) {
      return inet_ntop(AF_INET, &addr->in.sin_addr, str, INET_ADDRSTRLEN) != NULL;
    } else {
      ASSERT(addr->addr.sa_family == AF_INET6);
      return inet_ntop(AF_INET6, &addr->in6.sin6_addr, str, INET6_ADDRSTRLEN) !=
             NULL;
    }
  }
  
  static bool ShouldIncludeIfaAddrs(struct ifaddrs* ifa, int lookup_family) {
    if (ifa->ifa_addr == NULL) {
      // OpenVPN's virtual device tun0.
      return false;
    }
    int family = ifa->ifa_addr->sa_family;
    return ((lookup_family == family) ||
            (((lookup_family == AF_UNSPEC) &&
              ((family == AF_INET) || (family == AF_INET6)))));
  }
  
  bool SocketBase::ListInterfacesSupported() {
    return true;
  }
  
  AddressList<InterfaceSocketAddress>* SocketBase::ListInterfaces(
      int type,
      OSError** os_error) {
    struct ifaddrs* ifaddr;
  
    int status = NO_RETRY_EXPECTED(getifaddrs(&ifaddr));
    if (status != 0) {
      ASSERT(*os_error == NULL);
      *os_error =
          new OSError(status, gai_strerror(status), OSError::kGetAddressInfo);
      return NULL;
    }
  
    int lookup_family = SocketAddress::FromType(type);
  
    intptr_t count = 0;
    for (struct ifaddrs* ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
      if (ShouldIncludeIfaAddrs(ifa, lookup_family)) {
        count++;
      }
    }
  
    AddressList<InterfaceSocketAddress>* addresses =
        new AddressList<InterfaceSocketAddress>(count);
    int i = 0;
    for (struct ifaddrs* ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
      if (ShouldIncludeIfaAddrs(ifa, lookup_family)) {
        char* ifa_name = DartUtils::ScopedCopyCString(ifa->ifa_name);
        addresses->SetAt(
            i, new InterfaceSocketAddress(ifa->ifa_addr, ifa_name,
                                          if_nametoindex(ifa->ifa_name)));
        i++;
      }
    }
    freeifaddrs(ifaddr);
    return addresses;
  }
  
  void SocketBase::Close(intptr_t fd) {
    IOHandle* handle = reinterpret_cast<IOHandle*>(fd);
    ASSERT(handle->fd() >= 0);
    NO_RETRY_EXPECTED(close(handle->fd()));
  }
  
  bool SocketBase::GetNoDelay(intptr_t fd, bool* enabled) {
    errno = ENOSYS;
    return false;
  }
  
  bool SocketBase::SetNoDelay(intptr_t fd, bool enabled) {
    IOHandle* handle = reinterpret_cast<IOHandle*>(fd);
    int on = enabled ? 1 : 0;
    return NO_RETRY_EXPECTED(setsockopt(handle->fd(), IPPROTO_TCP, TCP_NODELAY,
                                        reinterpret_cast<char*>(&on),
                                        sizeof(on))) == 0;
  }
  
  bool SocketBase::GetMulticastLoop(intptr_t fd,
                                    intptr_t protocol,
                                    bool* enabled) {
    errno = ENOSYS;
    return false;
  }
  
  bool SocketBase::SetMulticastLoop(intptr_t fd,
                                    intptr_t protocol,
                                    bool enabled) {
    errno = ENOSYS;
    return false;
  }
  
  bool SocketBase::GetMulticastHops(intptr_t fd, intptr_t protocol, int* value) {
    errno = ENOSYS;
    return false;
  }
  
  bool SocketBase::SetMulticastHops(intptr_t fd, intptr_t protocol, int value) {
    errno = ENOSYS;
    return false;
  }
  
  bool SocketBase::GetBroadcast(intptr_t fd, bool* enabled) {
    errno = ENOSYS;
    return false;
  }
  
  bool SocketBase::SetBroadcast(intptr_t fd, bool enabled) {
    errno = ENOSYS;
    return false;
  }
  
  bool SocketBase::SetOption(intptr_t fd,
                             int level,
                             int option,
                             const char* data,
                             int length) {
    IOHandle* handle = reinterpret_cast<IOHandle*>(fd);
    return NO_RETRY_EXPECTED(
               setsockopt(handle->fd(), level, option, data, length)) == 0;
  }
  
  bool SocketBase::GetOption(intptr_t fd,
                             int level,
                             int option,
                             char* data,
                             unsigned int* length) {
    IOHandle* handle = reinterpret_cast<IOHandle*>(fd);
    socklen_t optlen = static_cast<socklen_t>(*length);
    auto result =
        NO_RETRY_EXPECTED(getsockopt(handle->fd(), level, option, data, &optlen));
    *length = static_cast<unsigned int>(optlen);
    return result == 0;
  }
  
  bool SocketBase::JoinMulticast(intptr_t fd,
                                 const RawAddr& addr,
                                 const RawAddr&,
                                 int interfaceIndex) {
    errno = ENOSYS;
    return false;
  }
  
  bool SocketBase::LeaveMulticast(intptr_t fd,
                                  const RawAddr& addr,
                                  const RawAddr&,
                                  int interfaceIndex) {
    errno = ENOSYS;
    return false;
  }
  
  }  // namespace bin
  }  // namespace dart
  
  #endif  // defined(HOST_OS_FUCHSIA)
  