fetched sources from android source. tested, they seem to work okay

ErrnoRestorer.h

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ERRNO_RESTORER_H
+#define ERRNO_RESTORER_H
+
+#include <errno.h>
+
+#include "bionic_macros.h"
+
+class ErrnoRestorer {
+ public:
+  explicit ErrnoRestorer() : saved_errno_(errno) {
+  }
+
+  ~ErrnoRestorer() {
+    errno = saved_errno_;
+  }
+
+  void override(int new_errno) {
+    saved_errno_ = new_errno;
+  }
+
+ private:
+  int saved_errno_;
+
+  DISALLOW_COPY_AND_ASSIGN(ErrnoRestorer);
+};
+
+#endif // ERRNO_RESTORER_H

bionic_macros.h

@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _BIONIC_MACROS_H_
+#define _BIONIC_MACROS_H_
+
+// Frameworks OpenGL code currently leaks this header and allows
+// collisions with other declarations, e.g., from libnativehelper.
+// TODO: Remove once cleaned up. b/18334516
+#if !defined(DISALLOW_COPY_AND_ASSIGN)
+// DISALLOW_COPY_AND_ASSIGN disallows the copy and operator= functions.
+// It goes in the private: declarations in a class.
+#define DISALLOW_COPY_AND_ASSIGN(TypeName) \
+  TypeName(const TypeName&) = delete;      \
+  void operator=(const TypeName&) = delete
+#endif  // !defined(DISALLOW_COPY_AND_ASSIGN)
+
+// A macro to disallow all the implicit constructors, namely the
+// default constructor, copy constructor and operator= functions.
+//
+// This should be used in the private: declarations for a class
+// that wants to prevent anyone from instantiating it. This is
+// especially useful for classes containing only static methods.
+#define DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \
+  TypeName() = delete;                           \
+  DISALLOW_COPY_AND_ASSIGN(TypeName)
+
+#define BIONIC_ALIGN(value, alignment) \
+  (((value) + (alignment) - 1) & ~((alignment) - 1))
+
+#define BIONIC_ROUND_UP_POWER_OF_2(value) \
+  ((sizeof(value) == 8) \
+    ? (1UL << (64 - __builtin_clzl(static_cast<unsigned long>(value)))) \
+    : (1UL << (32 - __builtin_clz(static_cast<unsigned int>(value)))))
+
+#endif // _BIONIC_MACROS_H_

bionic_netlink.cpp

@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "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
+ * COPYRIGHT OWNER 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.
+ */
+
+#include "bionic_netlink.h"
+
+#include <errno.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include "ErrnoRestorer.h"
+
+NetlinkConnection::NetlinkConnection() {
+  fd_ = -1;
+
+  // The kernel keeps packets under 8KiB (NLMSG_GOODSIZE),
+  // but that's a bit too large to go on the stack.
+  size_ = 8192;
+  data_ = new char[size_];
+}
+
+NetlinkConnection::~NetlinkConnection() {
+  ErrnoRestorer errno_restorer;
+  if (fd_ != -1) close(fd_);
+  delete[] data_;
+}
+
+bool NetlinkConnection::SendRequest(int type) {
+  // Rather than force all callers to check for the unlikely event of being
+  // unable to allocate 8KiB, check here.
+  if (data_ == nullptr) return false;
+
+  // Did we open a netlink socket yet?
+  if (fd_ == -1) {
+
+#ifndef SOCK_CLOEXEC
+#define SOCK_CLOEXEC O_CLOEXEC
+#endif
+
+    fd_ = socket(PF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, NETLINK_ROUTE);
+    if (fd_ == -1) return false;
+  }
+
+  // Construct and send the message.
+  struct NetlinkMessage {
+    nlmsghdr hdr;
+    rtgenmsg msg;
+  } request;
+  memset(&request, 0, sizeof(request));
+  request.hdr.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST;
+  request.hdr.nlmsg_type = type;
+  request.hdr.nlmsg_len = sizeof(request);
+  request.msg.rtgen_family = AF_UNSPEC; // All families.
+  return (TEMP_FAILURE_RETRY(send(fd_, &request, sizeof(request), 0)) == sizeof(request));
+}
+
+bool NetlinkConnection::ReadResponses(void callback(void*, nlmsghdr*), void* context) {
+  // Read through all the responses, handing interesting ones to the callback.
+  ssize_t bytes_read;
+  while ((bytes_read = TEMP_FAILURE_RETRY(recv(fd_, data_, size_, 0))) > 0) {
+    nlmsghdr* hdr = reinterpret_cast<nlmsghdr*>(data_);
+    for (; NLMSG_OK(hdr, static_cast<size_t>(bytes_read)); hdr = NLMSG_NEXT(hdr, bytes_read)) {
+      if (hdr->nlmsg_type == NLMSG_DONE) return true;
+      if (hdr->nlmsg_type == NLMSG_ERROR) {
+        nlmsgerr* err = reinterpret_cast<nlmsgerr*>(NLMSG_DATA(hdr));
+        errno = (hdr->nlmsg_len >= NLMSG_LENGTH(sizeof(nlmsgerr))) ? -err->error : EIO;
+        return false;
+      }
+      callback(context, hdr);
+    }
+  }
+
+  // We only get here if recv fails before we see a NLMSG_DONE.
+  return false;
+}

bionic_netlink.h

@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "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
+ * COPYRIGHT OWNER 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.
+ */
+
+#ifndef BIONIC_NETLINK_H
+#define BIONIC_NETLINK_H
+
+#include <sys/types.h>
+
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+
+struct nlmsghdr;
+
+class NetlinkConnection {
+ public:
+  NetlinkConnection();
+  ~NetlinkConnection();
+
+  bool SendRequest(int type);
+  bool ReadResponses(void callback(void*, nlmsghdr*), void* context);
+
+ private:
+  int fd_;
+  char* data_;
+  size_t size_;
+};
+
+#if !defined(__clang__)
+// GCC gets confused by NLMSG_DATA and doesn't realize that the old-style
+// cast is from a system header and should be ignored.
+#pragma GCC diagnostic ignored "-Wold-style-cast"
+#endif
+
+#endif

ifaddrs.cpp

@@ -0,0 +1,260 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "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
+ * COPYRIGHT OWNER 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.
+ */
+
+#include <ifaddrs.h>
+
+#include <errno.h>
+#include <linux/if_packet.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "ErrnoRestorer.h"
+
+#include "bionic_netlink.h"
+
+// The public ifaddrs struct is full of pointers. Rather than track several
+// different allocations, we use a maximally-sized structure with the public
+// part at offset 0, and pointers into its hidden tail.
+struct ifaddrs_storage {
+  // Must come first, so that `ifaddrs_storage` is-a `ifaddrs`.
+  ifaddrs ifa;
+
+  // The interface index, so we can match RTM_NEWADDR messages with
+  // earlier RTM_NEWLINK messages (to copy the interface flags).
+  int interface_index;
+
+  // Storage for the pointers in `ifa`.
+  sockaddr_storage addr;
+  sockaddr_storage netmask;
+  sockaddr_storage ifa_ifu;
+  char name[IFNAMSIZ + 1];
+
+  explicit ifaddrs_storage(ifaddrs** list) {
+    memset(this, 0, sizeof(*this));
+
+    // push_front onto `list`.
+    ifa.ifa_next = *list;
+    *list = reinterpret_cast<ifaddrs*>(this);
+  }
+
+  void SetAddress(int family, const void* data, size_t byteCount) {
+    // The kernel currently uses the order IFA_ADDRESS, IFA_LOCAL, IFA_BROADCAST
+    // in inet_fill_ifaddr, but let's not assume that will always be true...
+    if (ifa.ifa_addr == nullptr) {
+      // This is an IFA_ADDRESS and haven't seen an IFA_LOCAL yet, so assume this is the
+      // local address. SetLocalAddress will fix things if we later see an IFA_LOCAL.
+      ifa.ifa_addr = CopyAddress(family, data, byteCount, &addr);
+    } else {
+      // We already saw an IFA_LOCAL, which implies this is a destination address.
+      ifa.ifa_dstaddr = CopyAddress(family, data, byteCount, &ifa_ifu);
+    }
+  }
+
+  void SetBroadcastAddress(int family, const void* data, size_t byteCount) {
+    // ifa_broadaddr and ifa_dstaddr overlap in a union. Unfortunately, it's possible
+    // to have an interface with both. Keeping the last thing the kernel gives us seems
+    // to be glibc 2.19's behavior too, so our choice is being source compatible with
+    // badly-written code that assumes ifa_broadaddr and ifa_dstaddr are interchangeable
+    // or supporting interfaces with both addresses configured. My assumption is that
+    // bad code is more common than weird network interfaces...
+    ifa.ifa_broadaddr = CopyAddress(family, data, byteCount, &ifa_ifu);
+  }
+
+  void SetLocalAddress(int family, const void* data, size_t byteCount) {
+    // The kernel source says "for point-to-point IFA_ADDRESS is DESTINATION address,
+    // local address is supplied in IFA_LOCAL attribute".
+    //   -- http://lxr.free-electrons.com/source/include/uapi/linux/if_addr.h#L17
+
+    // So copy any existing IFA_ADDRESS into ifa_dstaddr...
+    if (ifa.ifa_addr != nullptr) {
+      ifa.ifa_dstaddr = reinterpret_cast<sockaddr*>(memcpy(&ifa_ifu, &addr, sizeof(addr)));
+    }
+    // ...and then put this IFA_LOCAL into ifa_addr.
+    ifa.ifa_addr = CopyAddress(family, data, byteCount, &addr);
+  }
+
+  // Netlink gives us the prefix length as a bit count. We need to turn
+  // that into a BSD-compatible netmask represented by a sockaddr*.
+  void SetNetmask(int family, size_t prefix_length) {
+    // ...and work out the netmask from the prefix length.
+    netmask.ss_family = family;
+    uint8_t* dst = SockaddrBytes(family, &netmask);
+    memset(dst, 0xff, prefix_length / 8);
+    if ((prefix_length % 8) != 0) {
+      dst[prefix_length/8] = (0xff << (8 - (prefix_length % 8)));
+    }
+    ifa.ifa_netmask = reinterpret_cast<sockaddr*>(&netmask);
+  }
+
+  void SetPacketAttributes(int ifindex, unsigned short hatype, unsigned char halen) {
+    sockaddr_ll* sll = reinterpret_cast<sockaddr_ll*>(&addr);
+    sll->sll_ifindex = ifindex;
+    sll->sll_hatype = hatype;
+    sll->sll_halen = halen;
+  }
+
+ private:
+  sockaddr* CopyAddress(int family, const void* data, size_t byteCount, sockaddr_storage* ss) {
+    // Netlink gives us the address family in the header, and the
+    // sockaddr_in or sockaddr_in6 bytes as the payload. We need to
+    // stitch the two bits together into the sockaddr that's part of
+    // our portable interface.
+    ss->ss_family = family;
+    memcpy(SockaddrBytes(family, ss), data, byteCount);
+
+    // For IPv6 we might also have to set the scope id.
+    if (family == AF_INET6 && (IN6_IS_ADDR_LINKLOCAL((const struct in6_addr *)data) || IN6_IS_ADDR_MC_LINKLOCAL((const struct in6_addr *)data))) {
+      reinterpret_cast<sockaddr_in6*>(ss)->sin6_scope_id = interface_index;
+    }
+
+    return reinterpret_cast<sockaddr*>(ss);
+  }
+
+  // Returns a pointer to the first byte in the address data (which is
+  // stored in network byte order).
+  uint8_t* SockaddrBytes(int family, sockaddr_storage* ss) {
+    if (family == AF_INET) {
+      sockaddr_in* ss4 = reinterpret_cast<sockaddr_in*>(ss);
+      return reinterpret_cast<uint8_t*>(&ss4->sin_addr);
+    } else if (family == AF_INET6) {
+      sockaddr_in6* ss6 = reinterpret_cast<sockaddr_in6*>(ss);
+      return reinterpret_cast<uint8_t*>(&ss6->sin6_addr);
+    } else if (family == AF_PACKET) {
+      sockaddr_ll* sll = reinterpret_cast<sockaddr_ll*>(ss);
+      return reinterpret_cast<uint8_t*>(&sll->sll_addr);
+    }
+    return nullptr;
+  }
+};
+
+static void __getifaddrs_callback(void* context, nlmsghdr* hdr) {
+  ifaddrs** out = reinterpret_cast<ifaddrs**>(context);
+
+  if (hdr->nlmsg_type == RTM_NEWLINK) {
+    ifinfomsg* ifi = reinterpret_cast<ifinfomsg*>(NLMSG_DATA(hdr));
+
+    // Create a new ifaddr entry, and set the interface index and flags.
+    ifaddrs_storage* new_addr = new ifaddrs_storage(out);
+    new_addr->interface_index = ifi->ifi_index;
+    new_addr->ifa.ifa_flags = ifi->ifi_flags;
+
+    // Go through the various bits of information and find the name.
+    rtattr* rta = IFLA_RTA(ifi);
+    size_t rta_len = IFLA_PAYLOAD(hdr);
+    while (RTA_OK(rta, rta_len)) {
+      if (rta->rta_type == IFLA_ADDRESS) {
+          if (RTA_PAYLOAD(rta) < sizeof(new_addr->addr)) {
+            new_addr->SetAddress(AF_PACKET, RTA_DATA(rta), RTA_PAYLOAD(rta));
+            new_addr->SetPacketAttributes(ifi->ifi_index, ifi->ifi_type, RTA_PAYLOAD(rta));
+          }
+      } else if (rta->rta_type == IFLA_BROADCAST) {
+          if (RTA_PAYLOAD(rta) < sizeof(new_addr->ifa_ifu)) {
+            new_addr->SetBroadcastAddress(AF_PACKET, RTA_DATA(rta), RTA_PAYLOAD(rta));
+            new_addr->SetPacketAttributes(ifi->ifi_index, ifi->ifi_type, RTA_PAYLOAD(rta));
+          }
+      } else if (rta->rta_type == IFLA_IFNAME) {
+          if (RTA_PAYLOAD(rta) < sizeof(new_addr->name)) {
+            memcpy(new_addr->name, RTA_DATA(rta), RTA_PAYLOAD(rta));
+            new_addr->ifa.ifa_name = new_addr->name;
+          }
+      }
+      rta = RTA_NEXT(rta, rta_len);
+    }
+  } else if (hdr->nlmsg_type == RTM_NEWADDR) {
+    ifaddrmsg* msg = reinterpret_cast<ifaddrmsg*>(NLMSG_DATA(hdr));
+
+    // We should already know about this from an RTM_NEWLINK message.
+    const ifaddrs_storage* addr = reinterpret_cast<const ifaddrs_storage*>(*out);
+    while (addr != nullptr && addr->interface_index != static_cast<int>(msg->ifa_index)) {
+      addr = reinterpret_cast<const ifaddrs_storage*>(addr->ifa.ifa_next);
+    }
+    // If this is an unknown interface, ignore whatever we're being told about it.
+    if (addr == nullptr) return;
+
+    // Create a new ifaddr entry and copy what we already know.
+    ifaddrs_storage* new_addr = new ifaddrs_storage(out);
+    // We can just copy the name rather than look for IFA_LABEL.
+    strcpy(new_addr->name, addr->name);
+    new_addr->ifa.ifa_name = new_addr->name;
+    new_addr->ifa.ifa_flags = addr->ifa.ifa_flags;
+    new_addr->interface_index = addr->interface_index;
+
+    // Go through the various bits of information and find the address
+    // and any broadcast/destination address.
+    rtattr* rta = IFA_RTA(msg);
+    size_t rta_len = IFA_PAYLOAD(hdr);
+    while (RTA_OK(rta, rta_len)) {
+      if (rta->rta_type == IFA_ADDRESS) {
+        if (msg->ifa_family == AF_INET || msg->ifa_family == AF_INET6) {
+          new_addr->SetAddress(msg->ifa_family, RTA_DATA(rta), RTA_PAYLOAD(rta));
+          new_addr->SetNetmask(msg->ifa_family, msg->ifa_prefixlen);
+        }
+      } else if (rta->rta_type == IFA_BROADCAST) {
+        if (msg->ifa_family == AF_INET) {
+          new_addr->SetBroadcastAddress(msg->ifa_family, RTA_DATA(rta), RTA_PAYLOAD(rta));
+        }
+      } else if (rta->rta_type == IFA_LOCAL) {
+        if (msg->ifa_family == AF_INET || msg->ifa_family == AF_INET6) {
+          new_addr->SetLocalAddress(msg->ifa_family, RTA_DATA(rta), RTA_PAYLOAD(rta));
+        }
+      }
+      rta = RTA_NEXT(rta, rta_len);
+    }
+  }
+}
+
+int getifaddrs(ifaddrs** out) {
+  // We construct the result directly into `out`, so terminate the list.
+  *out = nullptr;
+
+  // Open the netlink socket and ask for all the links and addresses.
+  NetlinkConnection nc;
+  bool okay = nc.SendRequest(RTM_GETLINK) && nc.ReadResponses(__getifaddrs_callback, out) &&
+              nc.SendRequest(RTM_GETADDR) && nc.ReadResponses(__getifaddrs_callback, out);
+  if (!okay) {
+    freeifaddrs(*out);
+    // Ensure that callers crash if they forget to check for success.
+    *out = nullptr;
+    return -1;
+  }
+
+  return 0;
+}
+
+void freeifaddrs(ifaddrs* list) {
+  while (list != nullptr) {
+    ifaddrs* current = list;
+    list = list->ifa_next;
+    free(current);
+  }
+}

ifaddrs.h

@@ -1,54 +1,59 @@
 /*
- * Copyright (c) 1995, 1999
+ * Copyright (C) 2015 The Android Open Source Project
- *	Berkeley Software Design, Inc.  All rights reserved.
+ * All rights reserved.
  *
  * 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 above copyright
+ *  * Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
+ *  * 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.
  *
- * THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``AS IS'' AND
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * ARE DISCLAIMED.  IN NO EVENT SHALL Berkeley Software Design, Inc. BE LIABLE
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * 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.
- *
- *	BSDI ifaddrs.h,v 2.5 2000/02/23 14:51:59 dab Exp
  */
 
-#ifndef	_IFADDRS_H_
+#ifndef _IFADDRS_H_
-#define	_IFADDRS_H_
+#define _IFADDRS_H_
+
+#include <sys/cdefs.h>
+#include <netinet/in.h>
+#include <sys/socket.h>
+
+__BEGIN_DECLS
 
 struct ifaddrs {
-	struct ifaddrs  *ifa_next;
+  struct ifaddrs* ifa_next;
-	char		*ifa_name;
+  char* ifa_name;
-	unsigned int	 ifa_flags;
+  unsigned int ifa_flags;
-	struct sockaddr	*ifa_addr;
+  struct sockaddr* ifa_addr;
-	struct sockaddr	*ifa_netmask;
+  struct sockaddr* ifa_netmask;
-	struct sockaddr	*ifa_dstaddr;
+  union {
-	void		*ifa_data;
+    struct sockaddr* ifu_broadaddr;
+    struct sockaddr* ifu_dstaddr;
+  } ifa_ifu;
+  void* ifa_data;
 };
 
-/*
+#define ifa_broadaddr ifa_ifu.ifu_broadaddr
- * This may have been defined in <net/if.h>.  Note that if <net/if.h> is
+#define ifa_dstaddr ifa_ifu.ifu_dstaddr
- * to be included it must be included before this header file.
- */
-#ifndef	ifa_broadaddr
-#define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
-#endif
 
-#include <sys/cdefs.h>
+void freeifaddrs(struct ifaddrs*);
+int getifaddrs(struct ifaddrs**);
 
-__BEGIN_DECLS
-extern int getifaddrs(struct ifaddrs **ifap);
-extern void freeifaddrs(struct ifaddrs *ifa);
 __END_DECLS
 
 #endif

ifaddrs.old.cpp.txt

@@ -22,6 +22,11 @@ ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
+#define TRACE_DEBUG_IFADDRS 1
+#ifdef TRACE_DEBUG_IFADDRS
+#include <QDebug>
+#endif
+
 #include "ifaddrs.h"
 
 #include <string.h>
@@ -33,6 +38,11 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <netinet/in.h>
 #include <linux/netlink.h>
 #include <linux/rtnetlink.h>
+#ifdef TRACE_DEBUG_IFADDRS
+#define trace(a) qDebug() << a;
+#else
+#define trace(a)
+#endif
 
 typedef struct NetlinkList
 {
@@ -119,12 +129,12 @@ static int netlink_recv(int p_socket, void *p_buffer, size_t p_len)
 static struct nlmsghdr *getNetlinkResponse(int p_socket, int *p_size, int *p_done)
 {
     size_t l_size = 4096;
-    void *l_buffer = NULL;
+    struct nlmsghdr * l_buffer = NULL;
     
     for(;;)
     {
-        free(l_buffer);
+        if(l_buffer) free(l_buffer);
-        l_buffer = malloc(l_size);
+        l_buffer = (struct nlmsghdr *)malloc(l_size);
         
         int l_read = netlink_recv(p_socket, l_buffer, l_size);
         *p_size = l_read;
@@ -137,7 +147,7 @@ static struct nlmsghdr *getNetlinkResponse(int p_socket, int *p_size, int *p_don
         {
             pid_t l_pid = getpid();
             struct nlmsghdr *l_hdr;
-            for(l_hdr = (struct nlmsghdr *)l_buffer; NLMSG_OK(l_hdr, (unsigned int)l_read); l_hdr = (struct nlmsghdr *)NLMSG_NEXT(l_hdr, l_read))
+            for(l_hdr = l_buffer; NLMSG_OK(l_hdr, (unsigned int)l_read); l_hdr = (struct nlmsghdr *)NLMSG_NEXT(l_hdr, l_read))
             {
                 if((pid_t)l_hdr->nlmsg_pid != l_pid || (int)l_hdr->nlmsg_seq != p_socket)
                 {
@@ -165,7 +175,7 @@ static struct nlmsghdr *getNetlinkResponse(int p_socket, int *p_size, int *p_don
 
 static NetlinkList *newListItem(struct nlmsghdr *p_data, unsigned int p_size)
 {
-    NetlinkList *l_item = malloc(sizeof(NetlinkList));
+    NetlinkList *l_item = (NetlinkList *)malloc(sizeof(NetlinkList));
     l_item->m_next = NULL;
     l_item->m_data = p_data;
     l_item->m_size = p_size;
@@ -238,7 +248,7 @@ static size_t calcAddrLen(sa_family_t p_family, int p_dataSize)
     }
 }
 
-static void makeSockaddr(sa_family_t p_family, struct sockaddr *p_dest, void *p_data, size_t p_size)
+static void makeSockaddr(sa_family_t p_family, struct sockaddr *p_dest, const char *p_data, size_t p_size)
 {
     switch(p_family)
     {
@@ -307,7 +317,10 @@ static void interpretLink(struct nlmsghdr *p_hdr, struct ifaddrs **p_links, stru
         }
     }
     
-    struct ifaddrs *l_entry = malloc(sizeof(struct ifaddrs) + l_nameSize + l_addrSize + l_dataSize);
+    struct ifaddrs *l_entry = (struct ifaddrs *)malloc(sizeof(struct ifaddrs) +
+                                                       l_nameSize +
+                                                       l_addrSize +
+                                                       l_dataSize);
     memset(l_entry, 0, sizeof(struct ifaddrs));
     l_entry->ifa_name = "";
     
@@ -320,7 +333,7 @@ static void interpretLink(struct nlmsghdr *p_hdr, struct ifaddrs **p_links, stru
     l_rtaSize = NLMSG_PAYLOAD(p_hdr, sizeof(struct ifinfomsg));
     for(l_rta = (struct rtattr *)(((char *)l_info) + NLMSG_ALIGN(sizeof(struct ifinfomsg))); RTA_OK(l_rta, l_rtaSize); l_rta = RTA_NEXT(l_rta, l_rtaSize))
     {
-        void *l_rtaData = RTA_DATA(l_rta);
+        const char *l_rtaData = (const char *)RTA_DATA(l_rta);
         size_t l_rtaDataSize = RTA_PAYLOAD(l_rta);
         switch(l_rta->rta_type)
         {
@@ -362,158 +375,235 @@ static void interpretLink(struct nlmsghdr *p_hdr, struct ifaddrs **p_links, stru
 
 static void interpretAddr(struct nlmsghdr *p_hdr, struct ifaddrs **p_links, struct ifaddrs **p_resultList)
 {
+    trace("interpretAddr.trace1")
     struct ifaddrmsg *l_info = (struct ifaddrmsg *)NLMSG_DATA(p_hdr);
 
+    trace("interpretAddr.trace2")
     size_t l_nameSize = 0;
     size_t l_addrSize = 0;
-    
+    trace("interpretAddr.trace3")
+
     int l_addedNetmask = 0;
     
+    trace("interpretAddr.trace4")
     size_t l_rtaSize = NLMSG_PAYLOAD(p_hdr, sizeof(struct ifaddrmsg));
     struct rtattr *l_rta;
+    trace("interpretAddr.trace5")
     for(l_rta = (struct rtattr *)(((char *)l_info) + NLMSG_ALIGN(sizeof(struct ifaddrmsg))); RTA_OK(l_rta, l_rtaSize); l_rta = RTA_NEXT(l_rta, l_rtaSize))
     {
+        trace("interpretAddr.trace6")
         void *l_rtaData = RTA_DATA(l_rta);
+        trace("interpretAddr.trace7")
         size_t l_rtaDataSize = RTA_PAYLOAD(l_rta);
+        trace("interpretAddr.trace8")
         if(l_info->ifa_family == AF_PACKET)
         {
+            trace("interpretAddr.trace9")
             continue;
         }
         
+        trace("interpretAddr.traceA")
         switch(l_rta->rta_type)
         {
             case IFA_ADDRESS:
             case IFA_LOCAL:
+                trace("interpretAddr.traceB")
                 if((l_info->ifa_family == AF_INET || l_info->ifa_family == AF_INET6) && !l_addedNetmask)
                 { // make room for netmask
+                    trace("interpretAddr.traceC")
                     l_addrSize += NLMSG_ALIGN(calcAddrLen(l_info->ifa_family, l_rtaDataSize));
+                    trace("interpretAddr.traceD")
                     l_addedNetmask = 1;
+                    trace("interpretAddr.traceE")
                 }
+                //TEST HYPN'S HYPOTHESIS
+                break;
+                //END OF TEST
             case IFA_BROADCAST:
+                trace("interpretAddr.traceF")
                 l_addrSize += NLMSG_ALIGN(calcAddrLen(l_info->ifa_family, l_rtaDataSize));
+                trace("interpretAddr.trace10")
                 break;
             case IFA_LABEL:
+                trace("interpretAddr.trace11")
                 l_nameSize += NLMSG_ALIGN(l_rtaSize + 1);
+                trace("interpretAddr.trace12")
                 break;
             default:
+                trace("interpretAddr.trace13")
                 break;
         }
+        trace("interpretAddr.trace14")
     }
     
-    struct ifaddrs *l_entry = malloc(sizeof(struct ifaddrs) + l_nameSize + l_addrSize);
+    trace("interpretAddr.trace15")
+    struct ifaddrs *l_entry = (struct ifaddrs *) malloc(sizeof(struct ifaddrs) + l_nameSize + l_addrSize);
+    trace("interpretAddr.trace16")
     memset(l_entry, 0, sizeof(struct ifaddrs));
+    trace("interpretAddr.trace17")
     l_entry->ifa_name = p_links[l_info->ifa_index - 1]->ifa_name;
     
+    trace("interpretAddr.trace18")
     char *l_name = ((char *)l_entry) + sizeof(struct ifaddrs);
+    trace("interpretAddr.trace19")
     char *l_addr = l_name + l_nameSize;
     
+    trace("interpretAddr.trace1A")
     l_entry->ifa_flags = l_info->ifa_flags | p_links[l_info->ifa_index - 1]->ifa_flags;
     
+    trace("interpretAddr.trace1B")
     l_rtaSize = NLMSG_PAYLOAD(p_hdr, sizeof(struct ifaddrmsg));
+    trace("interpretAddr.trace1C")
     for(l_rta = (struct rtattr *)(((char *)l_info) + NLMSG_ALIGN(sizeof(struct ifaddrmsg))); RTA_OK(l_rta, l_rtaSize); l_rta = RTA_NEXT(l_rta, l_rtaSize))
     {
-        void *l_rtaData = RTA_DATA(l_rta);
+        trace("interpretAddr.trace1D")
+        const char *l_rtaData = (const char *)RTA_DATA(l_rta);
         size_t l_rtaDataSize = RTA_PAYLOAD(l_rta);
+        trace("interpretAddr.trace1E")
         switch(l_rta->rta_type)
         {
             case IFA_ADDRESS:
             case IFA_BROADCAST:
             case IFA_LOCAL:
             {
+                trace("interpretAddr.trace1F")
                 size_t l_addrLen = calcAddrLen(l_info->ifa_family, l_rtaDataSize);
                 makeSockaddr(l_info->ifa_family, (struct sockaddr *)l_addr, l_rtaData, l_rtaDataSize);
+                trace("interpretAddr.trace20")
                 if(l_info->ifa_family == AF_INET6)
                 {
+                    trace("interpretAddr.trace21")
                     if(IN6_IS_ADDR_LINKLOCAL((struct in6_addr *)l_rtaData) || IN6_IS_ADDR_MC_LINKLOCAL((struct in6_addr *)l_rtaData))
                     {
+                        trace("interpretAddr.trace22")
                         ((struct sockaddr_in6 *)l_addr)->sin6_scope_id = l_info->ifa_index;
                     }
                 }
-                
+                trace("interpretAddr.trace23")
+
                 if(l_rta->rta_type == IFA_ADDRESS)
                 { // apparently in a point-to-point network IFA_ADDRESS contains the dest address and IFA_LOCAL contains the local address
+                    trace("interpretAddr.trace24")
                     if(l_entry->ifa_addr)
                     {
+                        trace("interpretAddr.trace25")
                         l_entry->ifa_dstaddr = (struct sockaddr *)l_addr;
                     }
                     else
                     {
+                        trace("interpretAddr.trace26")
                         l_entry->ifa_addr = (struct sockaddr *)l_addr;
                     }
                 }
                 else if(l_rta->rta_type == IFA_LOCAL)
                 {
+                    trace("interpretAddr.trace27")
                     if(l_entry->ifa_addr)
                     {
+                        trace("interpretAddr.trace28")
                         l_entry->ifa_dstaddr = l_entry->ifa_addr;
                     }
+                    trace("interpretAddr.trace29")
                     l_entry->ifa_addr = (struct sockaddr *)l_addr;
                 }
                 else
                 {
+                    trace("interpretAddr.trace2A")
                     l_entry->ifa_broadaddr = (struct sockaddr *)l_addr;
                 }
+                trace("interpretAddr.trace2B")
                 l_addr += NLMSG_ALIGN(l_addrLen);
+                trace("interpretAddr.trace2C")
                 break;
             }
             case IFA_LABEL:
+                trace("interpretAddr.trace2D")
                 strncpy(l_name, l_rtaData, l_rtaDataSize);
+                trace("interpretAddr.trace2E")
                 l_name[l_rtaDataSize] = '\0';
+                trace("interpretAddr.trace2F")
                 l_entry->ifa_name = l_name;
+                trace("interpretAddr.trace30")
                 break;
             default:
+                trace("interpretAddr.trace31")
                 break;
         }
+        trace("interpretAddr.trace32")
     }
     
+    trace("interpretAddr.trace33")
     if(l_entry->ifa_addr && (l_entry->ifa_addr->sa_family == AF_INET || l_entry->ifa_addr->sa_family == AF_INET6))
     {
+        trace("interpretAddr.trace34")
         unsigned l_maxPrefix = (l_entry->ifa_addr->sa_family == AF_INET ? 32 : 128);
         unsigned l_prefix = (l_info->ifa_prefixlen > l_maxPrefix ? l_maxPrefix : l_info->ifa_prefixlen);
         char l_mask[16] = {0};
         unsigned i;
+        trace("interpretAddr.trace35")
         for(i=0; i<(l_prefix/8); ++i)
         {
             l_mask[i] = 0xff;
         }
         l_mask[i] = 0xff << (8 - (l_prefix % 8));
         
+        trace("interpretAddr.trace36")
         makeSockaddr(l_entry->ifa_addr->sa_family, (struct sockaddr *)l_addr, l_mask, l_maxPrefix / 8);
         l_entry->ifa_netmask = (struct sockaddr *)l_addr;
+        trace("interpretAddr.trace37")
     }
     
+    trace("interpretAddr.trace38")
     addToEnd(p_resultList, l_entry);
+    trace("interpretAddr.trace39")
 }
 
 static void interpret(int p_socket, NetlinkList *p_netlinkList, struct ifaddrs **p_links, struct ifaddrs **p_resultList)
 {
+    trace("ifaddrs.interpret: entered");
     pid_t l_pid = getpid();
+    trace("ifaddrs.interpret: after getpid");
     for(; p_netlinkList; p_netlinkList = p_netlinkList->m_next)
     {
+        trace("ifaddrs.interpret: trace1");
         unsigned int l_nlsize = p_netlinkList->m_size;
+        trace("ifaddrs.interpret: trace2");
         struct nlmsghdr *l_hdr;
+        trace("ifaddrs.interpret: trace3");
         for(l_hdr = p_netlinkList->m_data; NLMSG_OK(l_hdr, l_nlsize); l_hdr = NLMSG_NEXT(l_hdr, l_nlsize))
         {
+            trace("ifaddrs.interpret: trace4");
             if((pid_t)l_hdr->nlmsg_pid != l_pid || (int)l_hdr->nlmsg_seq != p_socket)
             {
+                trace("ifaddrs.interpret: trace5");
                 continue;
             }
-            
+            trace("ifaddrs.interpret: trace6");
+
             if(l_hdr->nlmsg_type == NLMSG_DONE)
             {
+                trace("ifaddrs.interpret: trace7");
                 break;
             }
             
+            trace("ifaddrs.interpret: trace8");
             if(l_hdr->nlmsg_type == RTM_NEWLINK)
             {
+                trace("ifaddrs.interpret: trace9");
                 interpretLink(l_hdr, p_links, p_resultList);
+                trace("ifaddrs.interpret: traceA");
             }
             else if(l_hdr->nlmsg_type == RTM_NEWADDR)
             {
+                trace("ifaddrs.interpret: traceB");
                 interpretAddr(l_hdr, p_links, p_resultList);
+                trace("ifaddrs.interpret: traceC");
             }
+            trace("ifaddrs.interpret: traceD");
         }
+        trace("ifaddrs.interpret: traceE");
     }
+    trace("ifaddrs.interpret: leaving");
 }
 
 static unsigned countLinks(int p_socket, NetlinkList *p_netlinkList)
@@ -548,43 +638,64 @@ static unsigned countLinks(int p_socket, NetlinkList *p_netlinkList)
 
 int getifaddrs(struct ifaddrs **ifap)
 {
+    qDebug() << "entered getifaddrs";
     if(!ifap)
     {
+        trace("leaving getifaddrs: !ifap\n");
         return -1;
     }
+    trace("getifaddrs: before *ifap = NULL\n");
     *ifap = NULL;
     
+    trace("getifaddrs: before netlink_socket()\n");
     int l_socket = netlink_socket();
     if(l_socket < 0)
     {
+        trace("getifaddrs: leave, l_socket < 0\n");
         return -1;
     }
     
+    trace("getifaddrs: before getResultList(l_socket, RTM_GETLINK)\n");
     NetlinkList *l_linkResults = getResultList(l_socket, RTM_GETLINK);
     if(!l_linkResults)
     {
+        trace("getifaddrs: before close(l_socket)\n");
         close(l_socket);
+        trace("getifaddrs: before return -1\n");
         return -1;
     }
     
+    trace("getifaddrs: before getResultList(l_socket, RTM_GETADDR)\n");
     NetlinkList *l_addrResults = getResultList(l_socket, RTM_GETADDR);
     if(!l_addrResults)
     {
+        trace("getifaddrs: before close(l_socket)\n");
         close(l_socket);
+        trace("getifaddrs: before freeResultList\n");
         freeResultList(l_linkResults);
+        trace("getifaddrs: before return -1\n");
         return -1;
     }
     
+    trace("getifaddrs: before countLinks\n");
     unsigned l_numLinks = countLinks(l_socket, l_linkResults) + countLinks(l_socket, l_addrResults);
+    trace("getifaddrs: before struct ifaddrs *l_links\n");
     struct ifaddrs *l_links[l_numLinks];
+    trace("getifaddrs: before memset l_links\n");
     memset(l_links, 0, l_numLinks * sizeof(struct ifaddrs *));
     
+    trace("getifaddrs: before interpret 1\n");
     interpret(l_socket, l_linkResults, l_links, ifap);
+    trace("getifaddrs: before interpret 2\n");
     interpret(l_socket, l_addrResults, l_links, ifap);
 
+    trace("getifaddrs: before freeResultList(l_linkResults)\n");
     freeResultList(l_linkResults);
+    trace("getifaddrs: before freeResultList(l_addrResults)\n");
     freeResultList(l_addrResults);
+    trace("getifaddrs: before close(l_socket)\n");
     close(l_socket);
+    trace("getifaddrs: leaving, return 0\n");
     return 0;
 }
 

ifaddrs.old.h.txt

@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 1995, 1999
+ *	Berkeley Software Design, Inc.  All rights reserved.
+ *
+ * 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 above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``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 Berkeley Software Design, Inc. 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.
+ *
+ *	BSDI ifaddrs.h,v 2.5 2000/02/23 14:51:59 dab Exp
+ */
+
+#ifndef	_IFADDRS_H_
+#define	_IFADDRS_H_
+
+struct ifaddrs {
+	struct ifaddrs  *ifa_next;
+	char		*ifa_name;
+	unsigned int	 ifa_flags;
+	struct sockaddr	*ifa_addr;
+	struct sockaddr	*ifa_netmask;
+	struct sockaddr	*ifa_dstaddr;
+	void		*ifa_data;
+};
+
+/*
+ * This may have been defined in <net/if.h>.  Note that if <net/if.h> is
+ * to be included it must be included before this header file.
+ */
+#ifndef	ifa_broadaddr
+#define	ifa_broadaddr	ifa_dstaddr	/* broadcast address interface */
+#endif
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+extern int getifaddrs(struct ifaddrs **ifap);
+extern void freeifaddrs(struct ifaddrs *ifa);
+__END_DECLS
+
+#endif