Revert "Implement getifaddrs(3)/freeifaddrs(3)."

Werror build broken. Revert while working on a fix.

This reverts commit 0945ed5cc5921243724fed4465d20881f4891a8d.

Change-Id: I67edab7a7a3b9aa673ce9d14aa95380f947838a1
diff --git a/libc/Android.mk b/libc/Android.mk
index 83e1fb5..a399b89 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -149,7 +149,6 @@
     bionic/getpid.cpp \
     bionic/gettid.cpp \
     bionic/__gnu_basename.cpp \
-    bionic/ifaddrs.cpp \
     bionic/inotify_init.cpp \
     bionic/ioctl.cpp \
     bionic/lchown.cpp \
diff --git a/libc/bionic/ifaddrs.cpp b/libc/bionic/ifaddrs.cpp
deleted file mode 100644
index 5da6bcc..0000000
--- a/libc/bionic/ifaddrs.cpp
+++ /dev/null
@@ -1,235 +0,0 @@
-/*
- * 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/netlink.h>
-#include <linux/rtnetlink.h>
-#include <net/if.h>
-#include <netinet/in.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.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];
-
-  ifaddrs_storage(ifaddrs** list) {
-    memset(this, 0, sizeof(*this));
-
-    // push_front onto `list`.
-    ifa.ifa_next = *list;
-    *list = reinterpret_cast<ifaddrs*>(this);
-  }
-
-  // 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.
-  void SetAddress(int family, const void* data, size_t byteCount) {
-      addr.ss_family = family;
-      memcpy(SockaddrBytes(family, &addr), data, byteCount);
-      ifa.ifa_addr = reinterpret_cast<sockaddr*>(&addr);
-  }
-
-  void SetBroadcastAddress(int family, const void* data, size_t byteCount) {
-      ifa_ifu.ss_family = family;
-      memcpy(SockaddrBytes(family, &ifa_ifu), data, byteCount);
-      ifa.ifa_dstaddr = reinterpret_cast<sockaddr*>(&ifa_ifu);
-  }
-
-  // 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);
-  }
-
- private:
-  // 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);
-    }
-    return nullptr;
-  }
-};
-
-static void __handle_netlink_response(ifaddrs** out, nlmsghdr* hdr) {
-  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_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.
-    ifaddrs_storage* addr = reinterpret_cast<ifaddrs_storage*>(*out);
-    while (addr != nullptr && addr->interface_index != static_cast<int>(msg->ifa_index)) {
-      addr = reinterpret_cast<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) {
-          addr->SetAddress(msg->ifa_family, RTA_DATA(rta), RTA_PAYLOAD(rta));
-          addr->SetNetmask(msg->ifa_family, msg->ifa_prefixlen);
-        }
-      } else if (rta->rta_type == IFA_BROADCAST) {
-        if (msg->ifa_family == AF_INET || msg->ifa_family == AF_INET6) {
-          addr->SetBroadcastAddress(msg->ifa_family, RTA_DATA(rta), RTA_PAYLOAD(rta));
-        }
-      }
-      rta = RTA_NEXT(rta, rta_len);
-    }
-  }
-}
-
-static bool __send_netlink_request(int fd, int type) {
-  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));
-}
-
-static bool __read_netlink_responses(int fd, ifaddrs** out, char* buf, size_t buf_len) {
-  ssize_t bytes_read;
-  // Read through all the responses, handing interesting ones to __handle_netlink_response.
-  while ((bytes_read = TEMP_FAILURE_RETRY(recv(fd, buf, buf_len, 0))) > 0) {
-    nlmsghdr* hdr = reinterpret_cast<nlmsghdr*>(buf);
-    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) return false;
-      __handle_netlink_response(out, hdr);
-    }
-  }
-  // We only get here if recv fails before we see a NLMSG_DONE.
-  return false;
-}
-
-int getifaddrs(ifaddrs** out) {
-  // Make cleanup easy.
-  *out = nullptr;
-
-  // The kernel keeps packets under 8KiB (NLMSG_GOODSIZE),
-  // but that's a bit too large to go on the stack.
-  size_t buf_len = 8192;
-  char* buf = new char[buf_len];
-  if (buf == nullptr) return -1;
-
-  // Open the netlink socket and ask for all the links and addresses.
-  int fd = socket(PF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, NETLINK_ROUTE);
-  bool okay = fd != -1 &&
-      __send_netlink_request(fd, RTM_GETLINK) && __read_netlink_responses(fd, out, buf, buf_len) &&
-      __send_netlink_request(fd, RTM_GETADDR) && __read_netlink_responses(fd, out, buf, buf_len);
-
-  if (!okay) {
-    freeifaddrs(*out);
-    // Ensure that callers crash if they forget to check for success.
-    *out = nullptr;
-  }
-  {
-    int saved_errno = errno;
-    close(fd);
-    delete[] buf;
-    errno = saved_errno;
-  }
-  return okay ? 0 : -1;
-}
-
-void freeifaddrs(ifaddrs* list) {
-  while (list != nullptr) {
-    ifaddrs* current = list;
-    list = list->ifa_next;
-    free(current);
-  }
-}
diff --git a/libc/include/ifaddrs.h b/libc/include/ifaddrs.h
deleted file mode 100644
index 54a5a2c..0000000
--- a/libc/include/ifaddrs.h
+++ /dev/null
@@ -1,59 +0,0 @@
-/*
- * 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.
- */
-
-#ifndef _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;
-  char* ifa_name;
-  unsigned int ifa_flags;
-  struct sockaddr* ifa_addr;
-  struct sockaddr* ifa_netmask;
-  union {
-    struct sockaddr* ifu_broadaddr;
-    struct sockaddr* ifu_dstaddr;
-  } ifa_ifu;
-  void* ifa_data;
-};
-
-#define ifa_broadaddr ifa_ifu.ifu_broadaddr
-#define ifa_dstaddr ifa_ifu.ifu_dstaddr
-
-void freeifaddrs(struct ifaddrs*);
-int getifaddrs(struct ifaddrs**);
-
-__END_DECLS
-
-#endif
diff --git a/libc/libc.arm.brillo.map b/libc/libc.arm.brillo.map
index e09960b..4dd4481 100644
--- a/libc/libc.arm.brillo.map
+++ b/libc/libc.arm.brillo.map
@@ -1277,10 +1277,8 @@
     __pwrite64_chk;
     __write_chk;
     fileno_unlocked;
-    freeifaddrs;
     getgrgid_r;
     getgrnam_r;
-    getifaddrs;
     preadv;
     preadv64;
     prlimit; # arm mips x86
diff --git a/libc/libc.arm.map b/libc/libc.arm.map
index f24a867..1a666f4 100644
--- a/libc/libc.arm.map
+++ b/libc/libc.arm.map
@@ -1311,10 +1311,8 @@
     __pwrite64_chk;
     __write_chk;
     fileno_unlocked;
-    freeifaddrs;
     getgrgid_r;
     getgrnam_r;
-    getifaddrs;
     preadv;
     preadv64;
     prlimit; # arm mips x86
diff --git a/libc/libc.arm64.map b/libc/libc.arm64.map
index 0eb0275..8fa46a8 100644
--- a/libc/libc.arm64.map
+++ b/libc/libc.arm64.map
@@ -1156,10 +1156,8 @@
     __pwrite64_chk;
     __write_chk;
     fileno_unlocked;
-    freeifaddrs;
     getgrgid_r;
     getgrnam_r;
-    getifaddrs;
     preadv;
     preadv64;
     pthread_barrierattr_destroy;
diff --git a/libc/libc.map.txt b/libc/libc.map.txt
index 232f859..9eb8d01 100644
--- a/libc/libc.map.txt
+++ b/libc/libc.map.txt
@@ -1338,10 +1338,8 @@
     __pwrite64_chk;
     __write_chk;
     fileno_unlocked;
-    freeifaddrs;
     getgrgid_r;
     getgrnam_r;
-    getifaddrs;
     preadv;
     preadv64;
     prlimit; # arm mips x86
diff --git a/libc/libc.mips.brillo.map b/libc/libc.mips.brillo.map
index 5b7216b..d4a17ea 100644
--- a/libc/libc.mips.brillo.map
+++ b/libc/libc.mips.brillo.map
@@ -1240,10 +1240,8 @@
     __pwrite64_chk;
     __write_chk;
     fileno_unlocked;
-    freeifaddrs;
     getgrgid_r;
     getgrnam_r;
-    getifaddrs;
     preadv;
     preadv64;
     prlimit; # arm mips x86
diff --git a/libc/libc.mips.map b/libc/libc.mips.map
index 78b224b..5bee67e 100644
--- a/libc/libc.mips.map
+++ b/libc/libc.mips.map
@@ -1274,10 +1274,8 @@
     __pwrite64_chk;
     __write_chk;
     fileno_unlocked;
-    freeifaddrs;
     getgrgid_r;
     getgrnam_r;
-    getifaddrs;
     preadv;
     preadv64;
     prlimit; # arm mips x86
diff --git a/libc/libc.mips64.map b/libc/libc.mips64.map
index 0eb0275..8fa46a8 100644
--- a/libc/libc.mips64.map
+++ b/libc/libc.mips64.map
@@ -1156,10 +1156,8 @@
     __pwrite64_chk;
     __write_chk;
     fileno_unlocked;
-    freeifaddrs;
     getgrgid_r;
     getgrnam_r;
-    getifaddrs;
     preadv;
     preadv64;
     pthread_barrierattr_destroy;
diff --git a/libc/libc.x86.brillo.map b/libc/libc.x86.brillo.map
index 27a7778..f66f21b 100644
--- a/libc/libc.x86.brillo.map
+++ b/libc/libc.x86.brillo.map
@@ -1238,10 +1238,8 @@
     __pwrite64_chk;
     __write_chk;
     fileno_unlocked;
-    freeifaddrs;
     getgrgid_r;
     getgrnam_r;
-    getifaddrs;
     preadv;
     preadv64;
     prlimit; # arm mips x86
diff --git a/libc/libc.x86.map b/libc/libc.x86.map
index a4b4494..7120e7a 100644
--- a/libc/libc.x86.map
+++ b/libc/libc.x86.map
@@ -1272,10 +1272,8 @@
     __pwrite64_chk;
     __write_chk;
     fileno_unlocked;
-    freeifaddrs;
     getgrgid_r;
     getgrnam_r;
-    getifaddrs;
     preadv;
     preadv64;
     prlimit; # arm mips x86
diff --git a/libc/libc.x86_64.map b/libc/libc.x86_64.map
index 0eb0275..8fa46a8 100644
--- a/libc/libc.x86_64.map
+++ b/libc/libc.x86_64.map
@@ -1156,10 +1156,8 @@
     __pwrite64_chk;
     __write_chk;
     fileno_unlocked;
-    freeifaddrs;
     getgrgid_r;
     getgrnam_r;
-    getifaddrs;
     preadv;
     preadv64;
     pthread_barrierattr_destroy;
diff --git a/tests/Android.mk b/tests/Android.mk
index ff9e96a..86c141a 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -61,7 +61,6 @@
     ftw_test.cpp \
     getauxval_test.cpp \
     getcwd_test.cpp \
-    ifaddrs_test.cpp \
     inttypes_test.cpp \
     libc_logging_test.cpp \
     libgen_basename_test.cpp \
diff --git a/tests/ifaddrs_test.cpp b/tests/ifaddrs_test.cpp
deleted file mode 100644
index 67857cb..0000000
--- a/tests/ifaddrs_test.cpp
+++ /dev/null
@@ -1,38 +0,0 @@
-/*
- * Copyright (C) 2015 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.
- */
-
-#include <gtest/gtest.h>
-
-#include <ifaddrs.h>
-
-TEST(ifaddrs, freeifaddrs_null) {
-  freeifaddrs(nullptr);
-}
-
-TEST(ifaddrs, getifaddrs_smoke) {
-  ifaddrs* addrs = nullptr;
-
-  ASSERT_EQ(0, getifaddrs(&addrs));
-  ASSERT_TRUE(addrs != nullptr);
-
-  bool saw_loopback = false;
-  for (ifaddrs* addr = addrs; addr != nullptr; addr = addr->ifa_next) {
-    if (addr->ifa_name && strcmp(addr->ifa_name, "lo") == 0) saw_loopback = true;
-  }
-  ASSERT_TRUE(saw_loopback);
-
-  freeifaddrs(addrs);
-}