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, 173 insertions, 0 deletions

diff --git a/REORG.TODO/resolv/nss_dns/dns-canon.c b/REORG.TODO/resolv/nss_dns/dns-canon.c
new file mode 100644
index 0000000000..4276eb6542
--- /dev/null
+++ b/REORG.TODO/resolv/nss_dns/dns-canon.c
@@ -0,0 +1,173 @@
+/* Copyright (C) 2004-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2004.
+
+   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 <errno.h>
+#include <netdb.h>
+#include <resolv.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <arpa/nameser.h>
+#include <nsswitch.h>
+
+
+#if PACKETSZ > 65536
+# define MAXPACKET	PACKETSZ
+#else
+# define MAXPACKET	65536
+#endif
+
+
+/* We need this time later.  */
+typedef union querybuf
+{
+  HEADER hdr;
+  unsigned char buf[MAXPACKET];
+} querybuf;
+
+
+static const short int qtypes[] = { ns_t_a, ns_t_aaaa };
+#define nqtypes (sizeof (qtypes) / sizeof (qtypes[0]))
+
+
+enum nss_status
+_nss_dns_getcanonname_r (const char *name, char *buffer, size_t buflen,
+			 char **result,int *errnop, int *h_errnop)
+{
+  /* Just an alibi buffer, res_nquery will allocate a real buffer for
+     us.  */
+  unsigned char buf[20];
+  union
+  {
+    querybuf *buf;
+    unsigned char *ptr;
+  } ansp = { .ptr = buf };
+  enum nss_status status = NSS_STATUS_UNAVAIL;
+
+  for (int i = 0; i < nqtypes; ++i)
+    {
+      int r = __libc_res_nquery (&_res, name, ns_c_in, qtypes[i],
+				 buf, sizeof (buf), &ansp.ptr, NULL, NULL,
+				 NULL, NULL);
+      if (r > 0)
+	{
+	  /* We need to decode the response.  Just one question record.
+	     And if we got no answers we bail out, too.  */
+	  if (ansp.buf->hdr.qdcount != htons (1))
+	    continue;
+
+	  /* Number of answers.   */
+	  unsigned int ancount = ntohs (ansp.buf->hdr.ancount);
+
+	  /* Beginning and end of the buffer with query, answer, and the
+	     rest.  */
+	  unsigned char *ptr = &ansp.buf->buf[sizeof (HEADER)];
+	  unsigned char *endptr = ansp.ptr + r;
+
+	  /* Skip over the query.  This is the name, type, and class.  */
+	  int s = __dn_skipname (ptr, endptr);
+	  if (s < 0)
+	    {
+	    unavail:
+	      status = NSS_STATUS_UNAVAIL;
+	      break;
+	    }
+
+	  /* Skip over the name and the two 16-bit values containing type
+	     and class.  */
+	  ptr += s + 2 * sizeof (uint16_t);
+
+	  while (ancount-- > 0)
+	    {
+	      /* Now the reply.  First again the name from the query,
+		 then type, class, TTL, and the length of the RDATA.
+		 We remember the name start.  */
+	      unsigned char *namestart = ptr;
+	      s = __dn_skipname (ptr, endptr);
+	      if (s < 0)
+		goto unavail;
+
+	      ptr += s;
+
+	      /* Check that there are enough bytes for the RR
+		 metadata.  */
+	      if (endptr - ptr < 10)
+		goto unavail;
+
+	      /* Check whether type and class match.  */
+	      uint_fast16_t type;
+	      NS_GET16 (type, ptr);
+	      if (type == qtypes[i])
+		{
+		  /* We found the record.  */
+		  s = __dn_expand (ansp.buf->buf, endptr, namestart,
+				   buffer, buflen);
+		  if (s < 0)
+		    {
+		      if (errno != EMSGSIZE)
+			goto unavail;
+
+		      /* The buffer is too small.  */
+		      *errnop = ERANGE;
+		      status = NSS_STATUS_TRYAGAIN;
+		      h_errno = NETDB_INTERNAL;
+		    }
+		  else
+		    {
+		      /* Success.  */
+		      *result = buffer;
+		      status = NSS_STATUS_SUCCESS;
+		    }
+
+		  goto out;
+		}
+
+	      if (type != ns_t_cname)
+		goto unavail;
+
+	      if (__ns_get16 (ptr) != ns_c_in)
+		goto unavail;
+
+	      /* Also skip over class and TTL.  */
+	      ptr += sizeof (uint16_t) + sizeof (uint32_t);
+
+	      /* Skip over RDATA length and RDATA itself.  */
+	      uint16_t rdatalen = __ns_get16 (ptr);
+	      ptr += sizeof (uint16_t);
+	      /* Not enough room for RDATA.  */
+	      if (endptr - ptr < rdatalen)
+		goto unavail;
+	      ptr += rdatalen;
+	    }
+	}
+
+      /* Restore original buffer before retry.  */
+      if (ansp.ptr != buf)
+	{
+	  free (ansp.ptr);
+	  ansp.ptr = buf;
+	}
+    }
+
+ out:
+  *h_errnop = h_errno;
+
+  if (ansp.ptr != buf)
+    free (ansp.ptr);
+
+  return status;
+}