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, 459 insertions, 0 deletions

diff --git a/REORG.TODO/nscd/nscd_gethst_r.c b/REORG.TODO/nscd/nscd_gethst_r.c
new file mode 100644
index 0000000000..daa708b3d3
--- /dev/null
+++ b/REORG.TODO/nscd/nscd_gethst_r.c
@@ -0,0 +1,459 @@
+/* Copyright (C) 1998-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
+
+   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 <resolv/resolv-internal.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+#include <arpa/nameser.h>
+#include <not-cancel.h>
+
+#include "nscd-client.h"
+#include "nscd_proto.h"
+
+int __nss_not_use_nscd_hosts;
+
+static int nscd_gethst_r (const char *key, size_t keylen, request_type type,
+			  struct hostent *resultbuf, char *buffer,
+			  size_t buflen, struct hostent **result,
+			  int *h_errnop) internal_function;
+
+
+int
+__nscd_gethostbyname_r (const char *name, struct hostent *resultbuf,
+			char *buffer, size_t buflen, struct hostent **result,
+			int *h_errnop)
+{
+  request_type reqtype;
+
+  reqtype = res_use_inet6 () ? GETHOSTBYNAMEv6 : GETHOSTBYNAME;
+
+  return nscd_gethst_r (name, strlen (name) + 1, reqtype, resultbuf,
+			buffer, buflen, result, h_errnop);
+}
+
+
+int
+__nscd_gethostbyname2_r (const char *name, int af, struct hostent *resultbuf,
+			 char *buffer, size_t buflen, struct hostent **result,
+			 int *h_errnop)
+{
+  request_type reqtype;
+
+  reqtype = af == AF_INET6 ? GETHOSTBYNAMEv6 : GETHOSTBYNAME;
+
+  return nscd_gethst_r (name, strlen (name) + 1, reqtype, resultbuf,
+			buffer, buflen, result, h_errnop);
+}
+
+
+int
+__nscd_gethostbyaddr_r (const void *addr, socklen_t len, int type,
+			struct hostent *resultbuf, char *buffer, size_t buflen,
+			struct hostent **result, int *h_errnop)
+{
+  request_type reqtype;
+
+  if (!((len == INADDRSZ && type == AF_INET)
+	|| (len == IN6ADDRSZ && type == AF_INET6)))
+    /* LEN and TYPE do not match.  */
+    return -1;
+
+  reqtype = type == AF_INET6 ? GETHOSTBYADDRv6 : GETHOSTBYADDR;
+
+  return nscd_gethst_r (addr, len, reqtype, resultbuf, buffer, buflen, result,
+			h_errnop);
+}
+
+
+libc_locked_map_ptr (, __hst_map_handle) attribute_hidden;
+/* Note that we only free the structure if necessary.  The memory
+   mapping is not removed since it is not visible to the malloc
+   handling.  */
+libc_freeres_fn (hst_map_free)
+{
+  if (__hst_map_handle.mapped != NO_MAPPING)
+    {
+      void *p = __hst_map_handle.mapped;
+      __hst_map_handle.mapped = NO_MAPPING;
+      free (p);
+    }
+}
+
+
+uint32_t
+__nscd_get_nl_timestamp (void)
+{
+  uint32_t retval;
+  if (__nss_not_use_nscd_hosts != 0)
+    return 0;
+
+  /* __nscd_get_mapping can change hst_map_handle.mapped to NO_MAPPING.
+   However, __nscd_get_mapping assumes the prior value was not NO_MAPPING.
+   Thus we have to acquire the lock to prevent this thread from changing
+   hst_map_handle.mapped to NO_MAPPING while another thread is inside
+    __nscd_get_mapping.  */
+  if (!__nscd_acquire_maplock (&__hst_map_handle))
+    return 0;
+
+  struct mapped_database *map = __hst_map_handle.mapped;
+
+  if (map == NULL
+      || (map != NO_MAPPING
+	  && map->head->nscd_certainly_running == 0
+	  && map->head->timestamp + MAPPING_TIMEOUT < time (NULL)))
+    map = __nscd_get_mapping (GETFDHST, "hosts", &__hst_map_handle.mapped);
+
+  if (map == NO_MAPPING)
+    retval = 0;
+  else
+    retval = map->head->extra_data[NSCD_HST_IDX_CONF_TIMESTAMP];
+
+  /* Release the lock.  */
+  __hst_map_handle.lock = 0;
+
+  return retval;
+}
+
+
+int __nss_have_localdomain attribute_hidden;
+
+static int
+internal_function
+nscd_gethst_r (const char *key, size_t keylen, request_type type,
+	       struct hostent *resultbuf, char *buffer, size_t buflen,
+	       struct hostent **result, int *h_errnop)
+{
+  if (__glibc_unlikely (__nss_have_localdomain >= 0))
+    {
+      if (__nss_have_localdomain == 0)
+	__nss_have_localdomain = getenv ("LOCALDOMAIN") != NULL ? 1 : -1;
+      if (__nss_have_localdomain > 0)
+	{
+	  __nss_not_use_nscd_hosts = 1;
+	  return -1;
+	}
+    }
+
+  int gc_cycle;
+  int nretries = 0;
+
+  /* If the mapping is available, try to search there instead of
+     communicating with the nscd.  */
+  struct mapped_database *mapped;
+  mapped = __nscd_get_map_ref (GETFDHST, "hosts", &__hst_map_handle,
+			       &gc_cycle);
+
+ retry:;
+  const char *h_name = NULL;
+  const uint32_t *aliases_len = NULL;
+  const char *addr_list = NULL;
+  size_t addr_list_len = 0;
+  int retval = -1;
+  const char *recend = (const char *) ~UINTMAX_C (0);
+  int sock = -1;
+  hst_response_header hst_resp;
+  if (mapped != NO_MAPPING)
+    {
+      /* No const qualifier, as it can change during garbage collection.  */
+      struct datahead *found = __nscd_cache_search (type, key, keylen, mapped,
+						    sizeof hst_resp);
+      if (found != NULL)
+	{
+	  h_name = (char *) (&found->data[0].hstdata + 1);
+	  hst_resp = found->data[0].hstdata;
+	  aliases_len = (uint32_t *) (h_name + hst_resp.h_name_len);
+	  addr_list = ((char *) aliases_len
+		       + hst_resp.h_aliases_cnt * sizeof (uint32_t));
+	  addr_list_len = hst_resp.h_addr_list_cnt * INADDRSZ;
+	  recend = (const char *) found->data + found->recsize;
+	  /* Now check if we can trust hst_resp fields.  If GC is
+	     in progress, it can contain anything.  */
+	  if (mapped->head->gc_cycle != gc_cycle)
+	    {
+	      retval = -2;
+	      goto out;
+	    }
+
+#if !_STRING_ARCH_unaligned
+	  /* The aliases_len array in the mapped database might very
+	     well be unaligned.  We will access it word-wise so on
+	     platforms which do not tolerate unaligned accesses we
+	     need to make an aligned copy.  */
+	  if (((uintptr_t) aliases_len & (__alignof__ (*aliases_len) - 1))
+	      != 0)
+	    {
+	      uint32_t *tmp = alloca (hst_resp.h_aliases_cnt
+				      * sizeof (uint32_t));
+	      aliases_len = memcpy (tmp, aliases_len,
+				    hst_resp.h_aliases_cnt
+				    * sizeof (uint32_t));
+	    }
+#endif
+	  if (type != GETHOSTBYADDR && type != GETHOSTBYNAME)
+	    {
+	      if (hst_resp.h_length == INADDRSZ)
+		addr_list += addr_list_len;
+	      addr_list_len = hst_resp.h_addr_list_cnt * IN6ADDRSZ;
+	    }
+	  if (__builtin_expect ((const char *) addr_list + addr_list_len
+				> recend, 0))
+	    goto out;
+	}
+    }
+
+  if (h_name == NULL)
+    {
+      sock = __nscd_open_socket (key, keylen, type, &hst_resp,
+				 sizeof (hst_resp));
+      if (sock == -1)
+	{
+	  __nss_not_use_nscd_hosts = 1;
+	  goto out;
+	}
+    }
+
+  /* No value found so far.  */
+  *result = NULL;
+
+  if (__glibc_unlikely (hst_resp.found == -1))
+    {
+      /* The daemon does not cache this database.  */
+      __nss_not_use_nscd_hosts = 1;
+      goto out_close;
+    }
+
+  if (hst_resp.found == 1)
+    {
+      char *cp = buffer;
+      uintptr_t align1;
+      uintptr_t align2;
+      size_t total_len;
+      ssize_t cnt;
+      char *ignore;
+      int n;
+
+      /* A first check whether the buffer is sufficiently large is possible.  */
+      /* Now allocate the buffer the array for the group members.  We must
+	 align the pointer and the base of the h_addr_list pointers.  */
+      align1 = ((__alignof__ (char *) - (cp - ((char *) 0)))
+		& (__alignof__ (char *) - 1));
+      align2 = ((__alignof__ (char *) - ((cp + align1 + hst_resp.h_name_len)
+					 - ((char *) 0)))
+		& (__alignof__ (char *) - 1));
+      if (buflen < (align1 + hst_resp.h_name_len + align2
+		    + ((hst_resp.h_aliases_cnt + hst_resp.h_addr_list_cnt
+			+ 2)
+		       * sizeof (char *))
+		    + hst_resp.h_addr_list_cnt * (type == AF_INET
+						  ? INADDRSZ : IN6ADDRSZ)))
+	{
+	no_room:
+	  *h_errnop = NETDB_INTERNAL;
+	  __set_errno (ERANGE);
+	  retval = ERANGE;
+	  goto out_close;
+	}
+      cp += align1;
+
+      /* Prepare the result as far as we can.  */
+      resultbuf->h_aliases = (char **) cp;
+      cp += (hst_resp.h_aliases_cnt + 1) * sizeof (char *);
+      resultbuf->h_addr_list = (char **) cp;
+      cp += (hst_resp.h_addr_list_cnt + 1) * sizeof (char *);
+
+      resultbuf->h_name = cp;
+      cp += hst_resp.h_name_len + align2;
+
+      if (type == GETHOSTBYADDR || type == GETHOSTBYNAME)
+	{
+	  resultbuf->h_addrtype = AF_INET;
+	  resultbuf->h_length = INADDRSZ;
+	}
+      else
+	{
+	  resultbuf->h_addrtype = AF_INET6;
+	  resultbuf->h_length = IN6ADDRSZ;
+	}
+      for (cnt = 0; cnt < hst_resp.h_addr_list_cnt; ++cnt)
+	{
+	  resultbuf->h_addr_list[cnt] = cp;
+	  cp += resultbuf->h_length;
+	}
+      resultbuf->h_addr_list[cnt] = NULL;
+
+      if (h_name == NULL)
+	{
+	  struct iovec vec[4];
+
+	  vec[0].iov_base = resultbuf->h_name;
+	  vec[0].iov_len = hst_resp.h_name_len;
+	  total_len = hst_resp.h_name_len;
+	  n = 1;
+
+	  if (hst_resp.h_aliases_cnt > 0)
+	    {
+	      aliases_len = alloca (hst_resp.h_aliases_cnt
+				    * sizeof (uint32_t));
+	      vec[n].iov_base = (void *) aliases_len;
+	      vec[n].iov_len = hst_resp.h_aliases_cnt * sizeof (uint32_t);
+
+	      total_len += hst_resp.h_aliases_cnt * sizeof (uint32_t);
+	      ++n;
+	    }
+
+	  if (type == GETHOSTBYADDR || type == GETHOSTBYNAME)
+	    {
+	      vec[n].iov_base = resultbuf->h_addr_list[0];
+	      vec[n].iov_len = hst_resp.h_addr_list_cnt * INADDRSZ;
+
+	      total_len += hst_resp.h_addr_list_cnt * INADDRSZ;
+
+	      ++n;
+	    }
+	  else
+	    {
+	      if (hst_resp.h_length == INADDRSZ)
+		{
+		  ignore = alloca (hst_resp.h_addr_list_cnt * INADDRSZ);
+		  vec[n].iov_base = ignore;
+		  vec[n].iov_len = hst_resp.h_addr_list_cnt * INADDRSZ;
+
+		  total_len += hst_resp.h_addr_list_cnt * INADDRSZ;
+
+		  ++n;
+		}
+
+	      vec[n].iov_base = resultbuf->h_addr_list[0];
+	      vec[n].iov_len = hst_resp.h_addr_list_cnt * IN6ADDRSZ;
+
+	      total_len += hst_resp.h_addr_list_cnt * IN6ADDRSZ;
+
+	      ++n;
+	    }
+
+	  if ((size_t) __readvall (sock, vec, n) != total_len)
+	    goto out_close;
+	}
+      else
+	{
+	  memcpy (resultbuf->h_name, h_name, hst_resp.h_name_len);
+	  memcpy (resultbuf->h_addr_list[0], addr_list, addr_list_len);
+	}
+
+      /*  Now we also can read the aliases.  */
+      total_len = 0;
+      for (cnt = 0; cnt < hst_resp.h_aliases_cnt; ++cnt)
+	{
+	  resultbuf->h_aliases[cnt] = cp;
+	  cp += aliases_len[cnt];
+	  total_len += aliases_len[cnt];
+	}
+      resultbuf->h_aliases[cnt] = NULL;
+
+      if (__builtin_expect ((const char *) addr_list + addr_list_len
+			    + total_len > recend, 0))
+	{
+	  /* aliases_len array might contain garbage during nscd GC cycle,
+	     retry rather than fail in that case.  */
+	  if (addr_list != NULL && mapped->head->gc_cycle != gc_cycle)
+	    retval = -2;
+	  goto out_close;
+	}
+      /* See whether this would exceed the buffer capacity.  */
+      if (__glibc_unlikely (cp > buffer + buflen))
+	{
+	  /* aliases_len array might contain garbage during nscd GC cycle,
+	     retry rather than fail in that case.  */
+	  if (addr_list != NULL && mapped->head->gc_cycle != gc_cycle)
+	    {
+	      retval = -2;
+	      goto out_close;
+	    }
+	  goto no_room;
+	}
+
+      /* And finally read the aliases.  */
+      if (addr_list == NULL)
+	{
+	  if (total_len == 0
+	      || ((size_t) __readall (sock, resultbuf->h_aliases[0], total_len)
+		  == total_len))
+	    {
+	      retval = 0;
+	      *result = resultbuf;
+	    }
+	}
+      else
+	{
+	  memcpy (resultbuf->h_aliases[0],
+		  (const char *) addr_list + addr_list_len, total_len);
+
+	  /* Try to detect corrupt databases.  */
+	  if (resultbuf->h_name[hst_resp.h_name_len - 1] != '\0'
+	      || ({for (cnt = 0; cnt < hst_resp.h_aliases_cnt; ++cnt)
+		     if (resultbuf->h_aliases[cnt][aliases_len[cnt] - 1]
+			 != '\0')
+		       break;
+		   cnt < hst_resp.h_aliases_cnt; }))
+	    {
+	      /* We cannot use the database.  */
+	      if (mapped->head->gc_cycle != gc_cycle)
+		retval = -2;
+	      goto out_close;
+	    }
+
+	  retval = 0;
+	  *result = resultbuf;
+	}
+    }
+  else
+    {
+      /* Store the error number.  */
+      *h_errnop = hst_resp.error;
+
+      /* Set errno to 0 to indicate no error, just no found record.  */
+      __set_errno (0);
+      /* Even though we have not found anything, the result is zero.  */
+      retval = 0;
+    }
+
+ out_close:
+  if (sock != -1)
+    close_not_cancel_no_status (sock);
+ out:
+  if (__nscd_drop_map_ref (mapped, &gc_cycle) != 0)
+    {
+      /* When we come here this means there has been a GC cycle while we
+	 were looking for the data.  This means the data might have been
+	 inconsistent.  Retry if possible.  */
+      if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1)
+	{
+	  /* nscd is just running gc now.  Disable using the mapping.  */
+	  if (atomic_decrement_val (&mapped->counter) == 0)
+	    __nscd_unmap (mapped);
+	  mapped = NO_MAPPING;
+	}
+
+      if (retval != -1)
+	goto retry;
+    }
+
+  return retval;
+}