Prepare for radical source tree reorganization. zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 177 insertions, 0 deletions

diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/check_native.c b/REORG.TODO/sysdeps/unix/sysv/linux/check_native.c
new file mode 100644
index 0000000000..7e5a7c9be3
--- /dev/null
+++ b/REORG.TODO/sysdeps/unix/sysv/linux/check_native.c
@@ -0,0 +1,177 @@
+/* Determine whether interfaces use native transport.  Linux version.
+   Copyright (C) 2007-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <assert.h>
+#include <errno.h>
+#include <ifaddrs.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <net/if.h>
+#include <net/if_arp.h>
+#include <sys/ioctl.h>
+
+#include <asm/types.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+
+#include <not-cancel.h>
+
+#include "netlinkaccess.h"
+
+void
+__check_native (uint32_t a1_index, int *a1_native,
+		uint32_t a2_index, int *a2_native)
+{
+  int fd = __socket (PF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, NETLINK_ROUTE);
+
+  struct sockaddr_nl nladdr;
+  memset (&nladdr, '\0', sizeof (nladdr));
+  nladdr.nl_family = AF_NETLINK;
+
+  socklen_t addr_len = sizeof (nladdr);
+
+  if (fd < 0
+      || __bind (fd, (struct sockaddr *) &nladdr, sizeof (nladdr)) != 0
+      || __getsockname (fd, (struct sockaddr *) &nladdr, &addr_len) != 0)
+    return;
+
+  pid_t pid = nladdr.nl_pid;
+  struct req
+  {
+    struct nlmsghdr nlh;
+    struct rtgenmsg g;
+    /* struct rtgenmsg consists of a single byte.  This means there
+       are three bytes of padding included in the REQ definition.
+       We make them explicit here.  */
+    char pad[3];
+  } req;
+
+  req.nlh.nlmsg_len = sizeof (req);
+  req.nlh.nlmsg_type = RTM_GETLINK;
+  req.nlh.nlmsg_flags = NLM_F_ROOT | NLM_F_MATCH | NLM_F_REQUEST;
+  req.nlh.nlmsg_pid = 0;
+  req.nlh.nlmsg_seq = time (NULL);
+  req.g.rtgen_family = AF_UNSPEC;
+
+  assert (sizeof (req) - offsetof (struct req, pad) == 3);
+  memset (req.pad, '\0', sizeof (req.pad));
+
+  memset (&nladdr, '\0', sizeof (nladdr));
+  nladdr.nl_family = AF_NETLINK;
+
+#ifdef PAGE_SIZE
+  /* Help the compiler optimize out the malloc call if PAGE_SIZE
+     is constant and smaller or equal to PTHREAD_STACK_MIN/4.  */
+  const size_t buf_size = PAGE_SIZE;
+#else
+  const size_t buf_size = __getpagesize ();
+#endif
+  bool use_malloc = false;
+  char *buf;
+
+  if (__libc_use_alloca (buf_size))
+    buf = alloca (buf_size);
+  else
+    {
+      buf = malloc (buf_size);
+      if (buf != NULL)
+	use_malloc = true;
+      else
+	goto out_fail;
+    }
+
+  struct iovec iov = { buf, buf_size };
+
+  if (TEMP_FAILURE_RETRY (__sendto (fd, (void *) &req, sizeof (req), 0,
+				    (struct sockaddr *) &nladdr,
+				    sizeof (nladdr))) < 0)
+    goto out_fail;
+
+  bool done = false;
+  do
+    {
+      struct msghdr msg =
+	{
+	  .msg_name = (void *) &nladdr,
+	  .msg_namelen =  sizeof (nladdr),
+	  .msg_iov = &iov,
+	  .msg_iovlen = 1,
+	  .msg_control = NULL,
+	  .msg_controllen = 0,
+	  .msg_flags = 0
+	};
+
+      ssize_t read_len = TEMP_FAILURE_RETRY (__recvmsg (fd, &msg, 0));
+      __netlink_assert_response (fd, read_len);
+      if (read_len < 0)
+	goto out_fail;
+
+      if (msg.msg_flags & MSG_TRUNC)
+	goto out_fail;
+
+      struct nlmsghdr *nlmh;
+      for (nlmh = (struct nlmsghdr *) buf;
+	   NLMSG_OK (nlmh, (size_t) read_len);
+	   nlmh = (struct nlmsghdr *) NLMSG_NEXT (nlmh, read_len))
+	{
+	  if (nladdr.nl_pid != 0 || (pid_t) nlmh->nlmsg_pid != pid
+	      || nlmh->nlmsg_seq != req.nlh.nlmsg_seq)
+	    continue;
+
+	  if (nlmh->nlmsg_type == RTM_NEWLINK)
+	    {
+	      struct ifinfomsg *ifim = (struct ifinfomsg *) NLMSG_DATA (nlmh);
+	      int native = (ifim->ifi_type != ARPHRD_TUNNEL6
+			    && ifim->ifi_type != ARPHRD_TUNNEL
+			    && ifim->ifi_type != ARPHRD_SIT);
+
+	      if (a1_index == ifim->ifi_index)
+		{
+		  *a1_native = native;
+		  a1_index = 0xffffffffu;
+		}
+	      if (a2_index == ifim->ifi_index)
+		{
+		  *a2_native = native;
+		  a2_index = 0xffffffffu;
+		}
+
+	      if (a1_index == 0xffffffffu
+		  && a2_index == 0xffffffffu)
+		goto out;
+	    }
+	  else if (nlmh->nlmsg_type == NLMSG_DONE)
+	    /* We found the end, leave the loop.  */
+	    done = true;
+	}
+    }
+  while (! done);
+
+ out:
+  close_not_cancel_no_status (fd);
+
+  return;
+
+out_fail:
+  if (use_malloc)
+    free (buf);
+}