diff --git a/libelf/elf_begin.c b/libelf/elf_begin.c
new file mode 100644
index 0000000..b20ab4f
--- /dev/null
+++ b/libelf/elf_begin.c
@@ -0,0 +1,1180 @@
+/* Create descriptor for processing file.
+   Copyright (C) 1998-2010, 2012, 2014, 2015, 2016 Red Hat, Inc.
+   This file is part of elfutils.
+   Written by Ulrich Drepper <drepper@redhat.com>, 1998.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * the GNU General Public License as published by the Free
+       Software Foundation; either version 2 of the License, or (at
+       your option) any later version
+
+   or both in parallel, as here.
+
+   elfutils 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
+   General Public License for more details.
+
+   You should have received copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <assert.h>
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+#include <system.h>
+#include "libelfP.h"
+#include "common.h"
+
+
+/* Create descriptor for archive in memory.  */
+static inline Elf *
+file_read_ar (int fildes, void *map_address, off_t offset, size_t maxsize,
+	      Elf_Cmd cmd, Elf *parent)
+{
+  Elf *elf;
+
+  /* Create a descriptor.  */
+  elf = allocate_elf (fildes, map_address, offset, maxsize, cmd, parent,
+                      ELF_K_AR, 0);
+  if (elf != NULL)
+    {
+      /* We don't read all the symbol tables in advance.  All this will
+	 happen on demand.  */
+      elf->state.ar.offset = offset + SARMAG;
+
+      elf->state.ar.elf_ar_hdr.ar_rawname = elf->state.ar.raw_name;
+    }
+
+  return elf;
+}
+
+
+static size_t
+get_shnum (void *map_address, unsigned char *e_ident, int fildes, off_t offset,
+	   size_t maxsize)
+{
+  size_t result;
+  union
+  {
+    Elf32_Ehdr *e32;
+    Elf64_Ehdr *e64;
+    void *p;
+  } ehdr;
+  union
+  {
+    Elf32_Ehdr e32;
+    Elf64_Ehdr e64;
+  } ehdr_mem;
+  bool is32 = e_ident[EI_CLASS] == ELFCLASS32;
+
+  /* Make the ELF header available.  */
+  if (e_ident[EI_DATA] == MY_ELFDATA
+      && (ALLOW_UNALIGNED
+	  || (((size_t) e_ident
+	       & ((is32 ? __alignof__ (Elf32_Ehdr) : __alignof__ (Elf64_Ehdr))
+		  - 1)) == 0)))
+    ehdr.p = e_ident;
+  else
+    {
+      /* We already read the ELF header.  We have to copy the header
+	 since we possibly modify the data here and the caller
+	 expects the memory it passes in to be preserved.  */
+      ehdr.p = &ehdr_mem;
+
+      if (is32)
+	{
+	  if (ALLOW_UNALIGNED)
+	    {
+	      ehdr_mem.e32.e_shnum = ((Elf32_Ehdr *) e_ident)->e_shnum;
+	      ehdr_mem.e32.e_shoff = ((Elf32_Ehdr *) e_ident)->e_shoff;
+	    }
+	  else
+	    memcpy (&ehdr_mem, e_ident, sizeof (Elf32_Ehdr));
+
+	  if (e_ident[EI_DATA] != MY_ELFDATA)
+	    {
+	      CONVERT (ehdr_mem.e32.e_shnum);
+	      CONVERT (ehdr_mem.e32.e_shoff);
+	    }
+	}
+      else
+	{
+	  if (ALLOW_UNALIGNED)
+	    {
+	      ehdr_mem.e64.e_shnum = ((Elf64_Ehdr *) e_ident)->e_shnum;
+	      ehdr_mem.e64.e_shoff = ((Elf64_Ehdr *) e_ident)->e_shoff;
+	    }
+	  else
+	    memcpy (&ehdr_mem, e_ident, sizeof (Elf64_Ehdr));
+
+	  if (e_ident[EI_DATA] != MY_ELFDATA)
+	    {
+	      CONVERT (ehdr_mem.e64.e_shnum);
+	      CONVERT (ehdr_mem.e64.e_shoff);
+	    }
+	}
+    }
+
+  if (is32)
+    {
+      /* Get the number of sections from the ELF header.  */
+      result = ehdr.e32->e_shnum;
+
+      if (unlikely (result == 0) && ehdr.e32->e_shoff != 0)
+	{
+	  if (unlikely (ehdr.e32->e_shoff >= maxsize)
+	      || unlikely (maxsize - ehdr.e32->e_shoff < sizeof (Elf32_Shdr)))
+	    /* Cannot read the first section header.  */
+	    return 0;
+
+	  if (likely (map_address != NULL) && e_ident[EI_DATA] == MY_ELFDATA
+	      && (ALLOW_UNALIGNED
+		  || (((size_t) ((char *) map_address + ehdr.e32->e_shoff))
+		      & (__alignof__ (Elf32_Shdr) - 1)) == 0))
+	    /* We can directly access the memory.  */
+	    result = ((Elf32_Shdr *) ((char *) map_address + ehdr.e32->e_shoff
+				      + offset))->sh_size;
+	  else
+	    {
+	      Elf32_Word size;
+	      ssize_t r;
+
+	      if (likely (map_address != NULL))
+		/* gcc will optimize the memcpy to a simple memory
+		   access while taking care of alignment issues.  */
+		memcpy (&size, &((Elf32_Shdr *) ((char *) map_address
+						 + ehdr.e32->e_shoff
+						 + offset))->sh_size,
+			sizeof (Elf32_Word));
+	      else
+		if (unlikely ((r = pread_retry (fildes, &size,
+						sizeof (Elf32_Word),
+						offset + ehdr.e32->e_shoff
+						+ offsetof (Elf32_Shdr,
+							    sh_size)))
+			      != sizeof (Elf32_Word)))
+		  {
+		    if (r < 0)
+		      __libelf_seterrno (ELF_E_INVALID_FILE);
+		    else
+		      __libelf_seterrno (ELF_E_INVALID_ELF);
+		    return (size_t) -1l;
+		  }
+
+	      if (e_ident[EI_DATA] != MY_ELFDATA)
+		CONVERT (size);
+
+	      result = size;
+	    }
+	}
+
+      /* If the section headers were truncated, pretend none were there.  */
+      if (ehdr.e32->e_shoff > maxsize
+	  || maxsize - ehdr.e32->e_shoff < sizeof (Elf32_Shdr) * result)
+	result = 0;
+    }
+  else
+    {
+      /* Get the number of sections from the ELF header.  */
+      result = ehdr.e64->e_shnum;
+
+      if (unlikely (result == 0) && ehdr.e64->e_shoff != 0)
+	{
+	  if (unlikely (ehdr.e64->e_shoff >= maxsize)
+	      || unlikely (ehdr.e64->e_shoff + sizeof (Elf64_Shdr) > maxsize))
+	    /* Cannot read the first section header.  */
+	    return 0;
+
+	  Elf64_Xword size;
+	  if (likely (map_address != NULL) && e_ident[EI_DATA] == MY_ELFDATA
+	      && (ALLOW_UNALIGNED
+		  || (((size_t) ((char *) map_address + ehdr.e64->e_shoff))
+		      & (__alignof__ (Elf64_Shdr) - 1)) == 0))
+	    /* We can directly access the memory.  */
+	    size = ((Elf64_Shdr *) ((char *) map_address + ehdr.e64->e_shoff
+				    + offset))->sh_size;
+	  else
+	    {
+	      ssize_t r;
+	      if (likely (map_address != NULL))
+		/* gcc will optimize the memcpy to a simple memory
+		   access while taking care of alignment issues.  */
+		memcpy (&size, &((Elf64_Shdr *) ((char *) map_address
+						 + ehdr.e64->e_shoff
+						 + offset))->sh_size,
+			sizeof (Elf64_Xword));
+	      else
+		if (unlikely ((r = pread_retry (fildes, &size,
+						sizeof (Elf64_Xword),
+						offset + ehdr.e64->e_shoff
+						+ offsetof (Elf64_Shdr,
+							    sh_size)))
+			      != sizeof (Elf64_Xword)))
+		  {
+		    if (r < 0)
+		      __libelf_seterrno (ELF_E_INVALID_FILE);
+		    else
+		      __libelf_seterrno (ELF_E_INVALID_ELF);
+		    return (size_t) -1l;
+		  }
+
+	      if (e_ident[EI_DATA] != MY_ELFDATA)
+		CONVERT (size);
+	    }
+
+	  if (size > ~((GElf_Word) 0))
+	    {
+	      /* Invalid value, it is too large.  */
+	      __libelf_seterrno (ELF_E_INVALID_ELF);
+	      return (size_t) -1l;
+	    }
+
+	  result = size;
+	}
+
+      /* If the section headers were truncated, pretend none were there.  */
+      if (ehdr.e64->e_shoff > maxsize
+	  || maxsize - ehdr.e64->e_shoff < sizeof (Elf64_Shdr) * result)
+	result = 0;
+    }
+
+  return result;
+}
+
+
+/* Create descriptor for ELF file in memory.  */
+static Elf *
+file_read_elf (int fildes, void *map_address, unsigned char *e_ident,
+	       off_t offset, size_t maxsize, Elf_Cmd cmd, Elf *parent)
+{
+  /* Verify the binary is of the class we can handle.  */
+  if (unlikely ((e_ident[EI_CLASS] != ELFCLASS32
+		 && e_ident[EI_CLASS] != ELFCLASS64)
+		/* We also can only handle two encodings.  */
+		|| (e_ident[EI_DATA] != ELFDATA2LSB
+		    && e_ident[EI_DATA] != ELFDATA2MSB)))
+    {
+      /* Cannot handle this.  */
+      __libelf_seterrno (ELF_E_INVALID_ELF);
+      return NULL;
+    }
+
+  /* Determine the number of sections.  Returns -1 and sets libelf errno
+     if the file handle or elf file is invalid.  Returns zero if there
+     are no section headers (or they cannot be read).  */
+  size_t scncnt = get_shnum (map_address, e_ident, fildes, offset, maxsize);
+  if (scncnt == (size_t) -1l)
+    /* Could not determine the number of sections.  */
+    return NULL;
+
+  /* Check for too many sections.  */
+  if (e_ident[EI_CLASS] == ELFCLASS32)
+    {
+      if (scncnt > SIZE_MAX / (sizeof (Elf_Scn) + sizeof (Elf32_Shdr)))
+	{
+	  __libelf_seterrno (ELF_E_INVALID_ELF);
+	  return NULL;
+	}
+    }
+  else if (scncnt > SIZE_MAX / (sizeof (Elf_Scn) + sizeof (Elf64_Shdr)))
+    {
+      __libelf_seterrno (ELF_E_INVALID_ELF);
+      return NULL;
+    }
+
+  /* We can now allocate the memory.  Even if there are no section headers,
+     we allocate space for a zeroth section in case we need it later.  */
+  const size_t scnmax = (scncnt ?: (cmd == ELF_C_RDWR || cmd == ELF_C_RDWR_MMAP)
+			 ? 1 : 0);
+  Elf *elf = allocate_elf (fildes, map_address, offset, maxsize, cmd, parent,
+			   ELF_K_ELF, scnmax * sizeof (Elf_Scn));
+  if (elf == NULL)
+    /* Not enough memory.  allocate_elf will have set libelf errno.  */
+    return NULL;
+
+  assert ((unsigned int) scncnt == scncnt);
+  assert (offsetof (struct Elf, state.elf32.scns)
+	  == offsetof (struct Elf, state.elf64.scns));
+  elf->state.elf32.scns.cnt = scncnt;
+  elf->state.elf32.scns.max = scnmax;
+
+  /* Some more or less arbitrary value.  */
+  elf->state.elf.scnincr = 10;
+
+  /* Make the class easily available.  */
+  elf->class = e_ident[EI_CLASS];
+
+  if (e_ident[EI_CLASS] == ELFCLASS32)
+    {
+      /* This pointer might not be directly usable if the alignment is
+	 not sufficient for the architecture.  */
+      Elf32_Ehdr *ehdr = (Elf32_Ehdr *) ((char *) map_address + offset);
+
+      /* This is a 32-bit binary.  */
+      if (map_address != NULL && e_ident[EI_DATA] == MY_ELFDATA
+	  && (ALLOW_UNALIGNED
+	      || (((uintptr_t) ehdr) & (__alignof__ (Elf32_Ehdr) - 1)) == 0))
+	{
+	  /* We can use the mmapped memory.  */
+	  elf->state.elf32.ehdr = ehdr;
+	}
+      else
+	{
+	  /* Copy the ELF header.  */
+	  elf->state.elf32.ehdr = memcpy (&elf->state.elf32.ehdr_mem, e_ident,
+					  sizeof (Elf32_Ehdr));
+
+	  if (e_ident[EI_DATA] != MY_ELFDATA)
+	    {
+	      CONVERT (elf->state.elf32.ehdr_mem.e_type);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_machine);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_version);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_entry);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_phoff);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_shoff);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_flags);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_ehsize);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_phentsize);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_phnum);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_shentsize);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_shnum);
+	      CONVERT (elf->state.elf32.ehdr_mem.e_shstrndx);
+	    }
+	}
+
+      /* Don't precache the phdr pointer here.
+	 elf32_getphdr will validate it against the size when asked.  */
+
+      Elf32_Off e_shoff = elf->state.elf32.ehdr->e_shoff;
+      if (map_address != NULL && e_ident[EI_DATA] == MY_ELFDATA
+	  && cmd != ELF_C_READ_MMAP /* We need a copy to be able to write.  */
+	  && (ALLOW_UNALIGNED
+	      || (((uintptr_t) ((char *) ehdr + e_shoff)
+		   & (__alignof__ (Elf32_Shdr) - 1)) == 0)))
+	{
+	  if (unlikely (scncnt > 0 && e_shoff >= maxsize)
+	      || unlikely (maxsize - e_shoff
+			   < scncnt * sizeof (Elf32_Shdr)))
+	    {
+	    free_and_out:
+	      free (elf);
+	      __libelf_seterrno (ELF_E_INVALID_ELF);
+	      return NULL;
+	    }
+	  elf->state.elf32.shdr
+	    = (Elf32_Shdr *) ((char *) ehdr + e_shoff);
+
+	  for (size_t cnt = 0; cnt < scncnt; ++cnt)
+	    {
+	      elf->state.elf32.scns.data[cnt].index = cnt;
+	      elf->state.elf32.scns.data[cnt].elf = elf;
+	      elf->state.elf32.scns.data[cnt].shdr.e32 =
+		&elf->state.elf32.shdr[cnt];
+	      if (likely (elf->state.elf32.shdr[cnt].sh_offset < maxsize)
+		  && likely (elf->state.elf32.shdr[cnt].sh_size
+			     <= maxsize - elf->state.elf32.shdr[cnt].sh_offset))
+		elf->state.elf32.scns.data[cnt].rawdata_base =
+		  elf->state.elf32.scns.data[cnt].data_base =
+		  ((char *) map_address + offset
+		   + elf->state.elf32.shdr[cnt].sh_offset);
+	      elf->state.elf32.scns.data[cnt].list = &elf->state.elf32.scns;
+
+	      /* If this is a section with an extended index add a
+		 reference in the section which uses the extended
+		 index.  */
+	      if (elf->state.elf32.shdr[cnt].sh_type == SHT_SYMTAB_SHNDX
+		  && elf->state.elf32.shdr[cnt].sh_link < scncnt)
+		elf->state.elf32.scns.data[elf->state.elf32.shdr[cnt].sh_link].shndx_index
+		  = cnt;
+
+	      /* Set the own shndx_index field in case it has not yet
+		 been set.  */
+	      if (elf->state.elf32.scns.data[cnt].shndx_index == 0)
+		elf->state.elf32.scns.data[cnt].shndx_index = -1;
+	    }
+	}
+      else
+	{
+	  for (size_t cnt = 0; cnt < scncnt; ++cnt)
+	    {
+	      elf->state.elf32.scns.data[cnt].index = cnt;
+	      elf->state.elf32.scns.data[cnt].elf = elf;
+	      elf->state.elf32.scns.data[cnt].list = &elf->state.elf32.scns;
+	    }
+	}
+
+      /* So far only one block with sections.  */
+      elf->state.elf32.scns_last = &elf->state.elf32.scns;
+    }
+  else
+    {
+      /* This pointer might not be directly usable if the alignment is
+	 not sufficient for the architecture.  */
+      Elf64_Ehdr *ehdr = (Elf64_Ehdr *) ((char *) map_address + offset);
+
+      /* This is a 64-bit binary.  */
+      if (map_address != NULL && e_ident[EI_DATA] == MY_ELFDATA
+	  && (ALLOW_UNALIGNED
+	      || (((uintptr_t) ehdr) & (__alignof__ (Elf64_Ehdr) - 1)) == 0))
+	{
+	  /* We can use the mmapped memory.  */
+	  elf->state.elf64.ehdr = ehdr;
+	}
+      else
+	{
+	  /* Copy the ELF header.  */
+	  elf->state.elf64.ehdr = memcpy (&elf->state.elf64.ehdr_mem, e_ident,
+					  sizeof (Elf64_Ehdr));
+
+	  if (e_ident[EI_DATA] != MY_ELFDATA)
+	    {
+	      CONVERT (elf->state.elf64.ehdr_mem.e_type);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_machine);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_version);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_entry);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_phoff);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_shoff);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_flags);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_ehsize);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_phentsize);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_phnum);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_shentsize);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_shnum);
+	      CONVERT (elf->state.elf64.ehdr_mem.e_shstrndx);
+	    }
+	}
+
+      /* Don't precache the phdr pointer here.
+	 elf64_getphdr will validate it against the size when asked.  */
+
+      Elf64_Off e_shoff = elf->state.elf64.ehdr->e_shoff;
+      if (map_address != NULL && e_ident[EI_DATA] == MY_ELFDATA
+	  && cmd != ELF_C_READ_MMAP /* We need a copy to be able to write.  */
+	  && (ALLOW_UNALIGNED
+	      || (((uintptr_t) ((char *) ehdr + e_shoff)
+		   & (__alignof__ (Elf64_Shdr) - 1)) == 0)))
+	{
+	  if (unlikely (scncnt > 0 && e_shoff >= maxsize)
+	      || unlikely (maxsize - e_shoff
+			   < scncnt * sizeof (Elf64_Shdr)))
+	    goto free_and_out;
+	  elf->state.elf64.shdr
+	    = (Elf64_Shdr *) ((char *) ehdr + e_shoff);
+
+	  for (size_t cnt = 0; cnt < scncnt; ++cnt)
+	    {
+	      elf->state.elf64.scns.data[cnt].index = cnt;
+	      elf->state.elf64.scns.data[cnt].elf = elf;
+	      elf->state.elf64.scns.data[cnt].shdr.e64 =
+		&elf->state.elf64.shdr[cnt];
+	      if (likely (elf->state.elf64.shdr[cnt].sh_offset < maxsize)
+		  && likely (elf->state.elf64.shdr[cnt].sh_size
+			     <= maxsize - elf->state.elf64.shdr[cnt].sh_offset))
+		elf->state.elf64.scns.data[cnt].rawdata_base =
+		  elf->state.elf64.scns.data[cnt].data_base =
+		  ((char *) map_address + offset
+		   + elf->state.elf64.shdr[cnt].sh_offset);
+	      elf->state.elf64.scns.data[cnt].list = &elf->state.elf64.scns;
+
+	      /* If this is a section with an extended index add a
+		 reference in the section which uses the extended
+		 index.  */
+	      if (elf->state.elf64.shdr[cnt].sh_type == SHT_SYMTAB_SHNDX
+		  && elf->state.elf64.shdr[cnt].sh_link < scncnt)
+		elf->state.elf64.scns.data[elf->state.elf64.shdr[cnt].sh_link].shndx_index
+		  = cnt;
+
+	      /* Set the own shndx_index field in case it has not yet
+		 been set.  */
+	      if (elf->state.elf64.scns.data[cnt].shndx_index == 0)
+		elf->state.elf64.scns.data[cnt].shndx_index = -1;
+	    }
+	}
+      else
+	{
+	  for (size_t cnt = 0; cnt < scncnt; ++cnt)
+	    {
+	      elf->state.elf64.scns.data[cnt].index = cnt;
+	      elf->state.elf64.scns.data[cnt].elf = elf;
+	      elf->state.elf64.scns.data[cnt].list = &elf->state.elf64.scns;
+	    }
+	}
+
+      /* So far only one block with sections.  */
+      elf->state.elf64.scns_last = &elf->state.elf64.scns;
+    }
+
+  return elf;
+}
+
+
+Elf *
+internal_function
+__libelf_read_mmaped_file (int fildes, void *map_address,  off_t offset,
+			   size_t maxsize, Elf_Cmd cmd, Elf *parent)
+{
+  /* We have to find out what kind of file this is.  We handle ELF
+     files and archives.  To find out what we have we must look at the
+     header.  The header for an ELF file is EI_NIDENT bytes in size,
+     the header for an archive file SARMAG bytes long.  */
+  unsigned char *e_ident = (unsigned char *) map_address + offset;
+
+  /* See what kind of object we have here.  */
+  Elf_Kind kind = determine_kind (e_ident, maxsize);
+
+  switch (kind)
+    {
+    case ELF_K_ELF:
+      return file_read_elf (fildes, map_address, e_ident, offset, maxsize,
+			    cmd, parent);
+
+    case ELF_K_AR:
+      return file_read_ar (fildes, map_address, offset, maxsize, cmd, parent);
+
+    default:
+      break;
+    }
+
+  /* This case is easy.  Since we cannot do anything with this file
+     create a dummy descriptor.  */
+  return allocate_elf (fildes, map_address, offset, maxsize, cmd, parent,
+		       ELF_K_NONE, 0);
+}
+
+
+static Elf *
+read_unmmaped_file (int fildes, off_t offset, size_t maxsize, Elf_Cmd cmd,
+		    Elf *parent)
+{
+  /* We have to find out what kind of file this is.  We handle ELF
+     files and archives.  To find out what we have we must read the
+     header.  The identification header for an ELF file is EI_NIDENT
+     bytes in size, but we read the whole ELF header since we will
+     need it anyway later.  For archives the header in SARMAG bytes
+     long.  Read the maximum of these numbers.
+
+     XXX We have to change this for the extended `ar' format some day.
+
+     Use a union to ensure alignment.  We might later access the
+     memory as a ElfXX_Ehdr.  */
+  union
+  {
+    Elf64_Ehdr ehdr;
+    unsigned char header[MAX (sizeof (Elf64_Ehdr), SARMAG)];
+  } mem;
+
+  /* Read the head of the file.  */
+  ssize_t nread = pread_retry (fildes, mem.header,
+			       MIN (MAX (sizeof (Elf64_Ehdr), SARMAG),
+				    maxsize),
+			       offset);
+  if (unlikely (nread == -1))
+    {
+      /* We cannot even read the head of the file.  Maybe FILDES is associated
+	 with an unseekable device.  This is nothing we can handle.  */
+      __libelf_seterrno (ELF_E_INVALID_FILE);
+      return NULL;
+    }
+
+  /* See what kind of object we have here.  */
+  Elf_Kind kind = determine_kind (mem.header, nread);
+
+  switch (kind)
+    {
+    case ELF_K_AR:
+      return file_read_ar (fildes, NULL, offset, maxsize, cmd, parent);
+
+    case ELF_K_ELF:
+      /* Make sure at least the ELF header is contained in the file.  */
+      if ((size_t) nread >= (mem.header[EI_CLASS] == ELFCLASS32
+			     ? sizeof (Elf32_Ehdr) : sizeof (Elf64_Ehdr)))
+	return file_read_elf (fildes, NULL, mem.header, offset, maxsize, cmd,
+			      parent);
+      FALLTHROUGH;
+
+    default:
+      break;
+    }
+
+  /* This case is easy.  Since we cannot do anything with this file
+     create a dummy descriptor.  */
+  return allocate_elf (fildes, NULL, offset, maxsize, cmd, parent,
+		       ELF_K_NONE, 0);
+}
+
+
+/* Open a file for reading.  If possible we will try to mmap() the file.  */
+static struct Elf *
+read_file (int fildes, off_t offset, size_t maxsize,
+	   Elf_Cmd cmd, Elf *parent)
+{
+  void *map_address = NULL;
+  int use_mmap = (cmd == ELF_C_READ_MMAP || cmd == ELF_C_RDWR_MMAP
+		  || cmd == ELF_C_WRITE_MMAP
+		  || cmd == ELF_C_READ_MMAP_PRIVATE);
+
+  if (parent == NULL)
+    {
+      if (maxsize == ~((size_t) 0))
+	{
+	  /* We don't know in the moment how large the file is.
+	     Determine it now.  */
+	  struct stat st;
+
+	  if (fstat (fildes, &st) == 0
+	      && (sizeof (size_t) >= sizeof (st.st_size)
+		  || st.st_size <= ~((size_t) 0)))
+	    maxsize = (size_t) st.st_size;
+	}
+    }
+  else
+    {
+      /* The parent is already loaded.  Use it.  */
+      assert (maxsize != ~((size_t) 0));
+    }
+
+  if (use_mmap)
+    {
+      if (parent == NULL)
+	{
+	  /* We try to map the file ourself.  */
+	  map_address = mmap (NULL, maxsize, (cmd == ELF_C_READ_MMAP
+					      ? PROT_READ
+					      : PROT_READ|PROT_WRITE),
+			      cmd == ELF_C_READ_MMAP_PRIVATE
+			      || cmd == ELF_C_READ_MMAP
+			      ? MAP_PRIVATE : MAP_SHARED,
+			      fildes, offset);
+
+	  if (map_address == MAP_FAILED)
+	    map_address = NULL;
+	}
+      else
+	{
+	  map_address = parent->map_address;
+	}
+    }
+
+  /* If we have the file in memory optimize the access.  */
+  if (map_address != NULL)
+    {
+      assert (map_address != MAP_FAILED);
+
+      struct Elf *result = __libelf_read_mmaped_file (fildes, map_address,
+						      offset, maxsize, cmd,
+						      parent);
+
+      /* If something went wrong during the initialization unmap the
+	 memory if we mmaped here.  */
+      if (result == NULL
+	  && (parent == NULL
+	      || parent->map_address != map_address))
+	munmap (map_address, maxsize);
+      else if (parent == NULL)
+	/* Remember that we mmap()ed the memory.  */
+	result->flags |= ELF_F_MMAPPED;
+
+      return result;
+    }
+
+  /* Otherwise we have to do it the hard way.  We read as much as necessary
+     from the file whenever we need information which is not available.  */
+  return read_unmmaped_file (fildes, offset, maxsize, cmd, parent);
+}
+
+
+/* Find the entry with the long names for the content of this archive.  */
+static const char *
+read_long_names (Elf *elf)
+{
+  off_t offset = SARMAG;	/* This is the first entry.  */
+  struct ar_hdr hdrm;
+  struct ar_hdr *hdr;
+  char *newp;
+  size_t len;
+
+  while (1)
+    {
+      if (elf->map_address != NULL)
+	{
+	  if ((size_t) offset > elf->maximum_size
+	      || elf->maximum_size - offset < sizeof (struct ar_hdr))
+	    return NULL;
+
+	  /* The data is mapped.  */
+	  hdr = (struct ar_hdr *) (elf->map_address + offset);
+	}
+      else
+	{
+	  /* Read the header from the file.  */
+	  if (unlikely (pread_retry (elf->fildes, &hdrm, sizeof (hdrm),
+				     elf->start_offset + offset)
+			!= sizeof (hdrm)))
+	    return NULL;
+
+	  hdr = &hdrm;
+	}
+
+      len = atol (hdr->ar_size);
+
+      if (memcmp (hdr->ar_name, "//              ", 16) == 0)
+	break;
+
+      offset += sizeof (struct ar_hdr) + ((len + 1) & ~1l);
+    }
+
+  /* Due to the stupid format of the long name table entry (which are not
+     NUL terminted) we have to provide an appropriate representation anyhow.
+     Therefore we always make a copy which has the appropriate form.  */
+  newp = (char *) malloc (len);
+  if (newp != NULL)
+    {
+      char *runp;
+
+      if (elf->map_address != NULL)
+	{
+	  if (len > elf->maximum_size - offset - sizeof (struct ar_hdr))
+	    goto too_much;
+	  /* Simply copy it over.  */
+	  elf->state.ar.long_names = (char *) memcpy (newp,
+						      elf->map_address + offset
+						      + sizeof (struct ar_hdr),
+						      len);
+	}
+      else
+	{
+	  if (unlikely ((size_t) pread_retry (elf->fildes, newp, len,
+					      elf->start_offset + offset
+					      + sizeof (struct ar_hdr))
+			!= len))
+	    {
+	    too_much:
+	      /* We were not able to read all data.  */
+	      free (newp);
+	      elf->state.ar.long_names = NULL;
+	      return NULL;
+	    }
+	  elf->state.ar.long_names = newp;
+	}
+
+      elf->state.ar.long_names_len = len;
+
+      /* Now NUL-terminate the strings.  */
+      runp = newp;
+      while (1)
+        {
+	  char *startp = runp;
+	  runp = (char *) memchr (runp, '/', newp + len - runp);
+	  if (runp == NULL)
+	    {
+	      /* This was the last entry.  Clear any left overs.  */
+	      memset (startp, '\0', newp + len - startp);
+	      break;
+	    }
+
+	  /* NUL-terminate the string.  */
+	  *runp++ = '\0';
+
+	  /* A sanity check.  Somebody might have generated invalid
+	     archive.  */
+	  if (runp >= newp + len)
+	    break;
+	}
+    }
+
+  return newp;
+}
+
+
+/* Read the next archive header.  */
+int
+internal_function
+__libelf_next_arhdr_wrlock (Elf *elf)
+{
+  struct ar_hdr *ar_hdr;
+  Elf_Arhdr *elf_ar_hdr;
+
+  if (elf->map_address != NULL)
+    {
+      /* See whether this entry is in the file.  */
+      if (unlikely ((size_t) elf->state.ar.offset
+		    > elf->start_offset + elf->maximum_size
+		    || (elf->start_offset + elf->maximum_size
+			- elf->state.ar.offset) < sizeof (struct ar_hdr)))
+	{
+	  /* This record is not anymore in the file.  */
+	  __libelf_seterrno (ELF_E_RANGE);
+	  return -1;
+	}
+      ar_hdr = (struct ar_hdr *) (elf->map_address + elf->state.ar.offset);
+    }
+  else
+    {
+      ar_hdr = &elf->state.ar.ar_hdr;
+
+      if (unlikely (pread_retry (elf->fildes, ar_hdr, sizeof (struct ar_hdr),
+				 elf->state.ar.offset)
+		    != sizeof (struct ar_hdr)))
+	{
+	  /* Something went wrong while reading the file.  */
+	  __libelf_seterrno (ELF_E_RANGE);
+	  return -1;
+	}
+    }
+
+  /* One little consistency check.  */
+  if (unlikely (memcmp (ar_hdr->ar_fmag, ARFMAG, 2) != 0))
+    {
+      /* This is no valid archive.  */
+      __libelf_seterrno (ELF_E_ARCHIVE_FMAG);
+      return -1;
+    }
+
+  /* Copy the raw name over to a NUL terminated buffer.  */
+  *((char *) mempcpy (elf->state.ar.raw_name, ar_hdr->ar_name, 16)) = '\0';
+
+  elf_ar_hdr = &elf->state.ar.elf_ar_hdr;
+
+  /* Now convert the `struct ar_hdr' into `Elf_Arhdr'.
+     Determine whether this is a special entry.  */
+  if (ar_hdr->ar_name[0] == '/')
+    {
+      if (ar_hdr->ar_name[1] == ' '
+	  && memcmp (ar_hdr->ar_name, "/               ", 16) == 0)
+	/* This is the index.  */
+	elf_ar_hdr->ar_name = memcpy (elf->state.ar.ar_name, "/", 2);
+      else if (ar_hdr->ar_name[1] == 'S'
+	       && memcmp (ar_hdr->ar_name, "/SYM64/         ", 16) == 0)
+	/* 64-bit index.  */
+	elf_ar_hdr->ar_name = memcpy (elf->state.ar.ar_name, "/SYM64/", 8);
+      else if (ar_hdr->ar_name[1] == '/'
+	       && memcmp (ar_hdr->ar_name, "//              ", 16) == 0)
+	/* This is the array with the long names.  */
+	elf_ar_hdr->ar_name = memcpy (elf->state.ar.ar_name, "//", 3);
+      else if (likely  (isdigit (ar_hdr->ar_name[1])))
+	{
+	  size_t offset;
+
+	  /* This is a long name.  First we have to read the long name
+	     table, if this hasn't happened already.  */
+	  if (unlikely (elf->state.ar.long_names == NULL
+			&& read_long_names (elf) == NULL))
+	    {
+	      /* No long name table although it is reference.  The archive is
+		 broken.  */
+	      __libelf_seterrno (ELF_E_INVALID_ARCHIVE);
+	      return -1;
+	    }
+
+	  offset = atol (ar_hdr->ar_name + 1);
+	  if (unlikely (offset >= elf->state.ar.long_names_len))
+	    {
+	      /* The index in the long name table is larger than the table.  */
+	      __libelf_seterrno (ELF_E_INVALID_ARCHIVE);
+	      return -1;
+	    }
+	  elf_ar_hdr->ar_name = elf->state.ar.long_names + offset;
+	}
+      else
+	{
+	  /* This is none of the known special entries.  */
+	  __libelf_seterrno (ELF_E_INVALID_ARCHIVE);
+	  return -1;
+	}
+    }
+  else
+    {
+      char *endp;
+
+      /* It is a normal entry.  Copy over the name.  */
+      endp = (char *) memccpy (elf->state.ar.ar_name, ar_hdr->ar_name,
+			       '/', 16);
+      if (endp != NULL)
+	endp[-1] = '\0';
+      else
+	{
+	  /* In the old BSD style of archive, there is no / terminator.
+	     Instead, there is space padding at the end of the name.  */
+	  size_t i = 15;
+	  do
+	    elf->state.ar.ar_name[i] = '\0';
+	  while (i > 0 && elf->state.ar.ar_name[--i] == ' ');
+	}
+
+      elf_ar_hdr->ar_name = elf->state.ar.ar_name;
+    }
+
+  if (unlikely (ar_hdr->ar_size[0] == ' '))
+    /* Something is really wrong.  We cannot live without a size for
+       the member since it will not be possible to find the next
+       archive member.  */
+    {
+      __libelf_seterrno (ELF_E_INVALID_ARCHIVE);
+      return -1;
+    }
+
+  /* Since there are no specialized functions to convert ASCII to
+     time_t, uid_t, gid_t, mode_t, and off_t we use either atol or
+     atoll depending on the size of the types.  We are also prepared
+     for the case where the whole field in the `struct ar_hdr' is
+     filled in which case we cannot simply use atol/l but instead have
+     to create a temporary copy.  */
+
+#define INT_FIELD(FIELD)						      \
+  do									      \
+    {									      \
+      char buf[sizeof (ar_hdr->FIELD) + 1];				      \
+      const char *string = ar_hdr->FIELD;				      \
+      if (ar_hdr->FIELD[sizeof (ar_hdr->FIELD) - 1] != ' ')		      \
+	{								      \
+	  *((char *) mempcpy (buf, ar_hdr->FIELD, sizeof (ar_hdr->FIELD)))  \
+	    = '\0';							      \
+	  string = buf;							      \
+	}								      \
+      if (sizeof (elf_ar_hdr->FIELD) <= sizeof (long int))		      \
+	elf_ar_hdr->FIELD = (__typeof (elf_ar_hdr->FIELD)) atol (string);     \
+      else								      \
+	elf_ar_hdr->FIELD = (__typeof (elf_ar_hdr->FIELD)) atoll (string);    \
+    }									      \
+  while (0)
+
+  INT_FIELD (ar_date);
+  INT_FIELD (ar_uid);
+  INT_FIELD (ar_gid);
+  INT_FIELD (ar_mode);
+  INT_FIELD (ar_size);
+
+  if (elf_ar_hdr->ar_size < 0)
+    {
+      __libelf_seterrno (ELF_E_INVALID_ARCHIVE);
+      return -1;
+    }
+
+  /* Truncated file?  */
+  size_t maxsize;
+  maxsize = (elf->start_offset + elf->maximum_size
+	     - elf->state.ar.offset - sizeof (struct ar_hdr));
+  if ((size_t) elf_ar_hdr->ar_size > maxsize)
+    elf_ar_hdr->ar_size = maxsize;
+
+  return 0;
+}
+
+
+/* We were asked to return a clone of an existing descriptor.  This
+   function must be called with the lock on the parent descriptor
+   being held. */
+static Elf *
+dup_elf (int fildes, Elf_Cmd cmd, Elf *ref)
+{
+  struct Elf *result;
+
+  if (fildes == -1)
+    /* Allow the user to pass -1 as the file descriptor for the new file.  */
+    fildes = ref->fildes;
+  /* The file descriptor better should be the same.  If it was disconnected
+     already (using `elf_cntl') we do not test it.  */
+  else if (unlikely (ref->fildes != -1 && fildes != ref->fildes))
+    {
+      __libelf_seterrno (ELF_E_FD_MISMATCH);
+      return NULL;
+    }
+
+  /* The mode must allow reading.  I.e., a descriptor creating with a
+     command different then ELF_C_READ, ELF_C_WRITE and ELF_C_RDWR is
+     not allowed.  */
+  if (unlikely (ref->cmd != ELF_C_READ && ref->cmd != ELF_C_READ_MMAP
+		&& ref->cmd != ELF_C_WRITE && ref->cmd != ELF_C_WRITE_MMAP
+		&& ref->cmd != ELF_C_RDWR && ref->cmd != ELF_C_RDWR_MMAP
+		&& ref->cmd != ELF_C_READ_MMAP_PRIVATE))
+    {
+      __libelf_seterrno (ELF_E_INVALID_OP);
+      return NULL;
+    }
+
+  /* Now it is time to distinguish between reading normal files and
+     archives.  Normal files can easily be handled be incrementing the
+     reference counter and return the same descriptor.  */
+  if (ref->kind != ELF_K_AR)
+    {
+      ++ref->ref_count;
+      return ref;
+    }
+
+  /* This is an archive.  We must create a descriptor for the archive
+     member the internal pointer of the archive file desriptor is
+     pointing to.  First read the header of the next member if this
+     has not happened already.  */
+  if (ref->state.ar.elf_ar_hdr.ar_name == NULL
+      && __libelf_next_arhdr_wrlock (ref) != 0)
+    /* Something went wrong.  Maybe there is no member left.  */
+    return NULL;
+
+  /* We have all the information we need about the next archive member.
+     Now create a descriptor for it.  */
+  result = read_file (fildes, ref->state.ar.offset + sizeof (struct ar_hdr),
+		      ref->state.ar.elf_ar_hdr.ar_size, cmd, ref);
+
+  /* Enlist this new descriptor in the list of children.  */
+  if (result != NULL)
+    {
+      result->next = ref->state.ar.children;
+      ref->state.ar.children = result;
+    }
+
+  return result;
+}
+
+
+/* Return desriptor for empty file ready for writing.  */
+static struct Elf *
+write_file (int fd, Elf_Cmd cmd)
+{
+  /* We simply create an empty `Elf' structure.  */
+#define NSCNSALLOC	10
+  Elf *result = allocate_elf (fd, NULL, 0, 0, cmd, NULL, ELF_K_ELF,
+			      NSCNSALLOC * sizeof (Elf_Scn));
+
+  if (result != NULL)
+    {
+      /* We have to write to the file in any case.  */
+      result->flags = ELF_F_DIRTY;
+
+      /* Some more or less arbitrary value.  */
+      result->state.elf.scnincr = NSCNSALLOC;
+
+      /* We have allocated room for some sections.  */
+      assert (offsetof (struct Elf, state.elf32.scns)
+	      == offsetof (struct Elf, state.elf64.scns));
+      result->state.elf.scns_last = &result->state.elf32.scns;
+      result->state.elf32.scns.max = NSCNSALLOC;
+    }
+
+  return result;
+}
+
+/* Lock if necessary before dup an archive.  */
+static inline Elf *
+lock_dup_elf (int fildes, Elf_Cmd cmd, Elf *ref)
+{
+  /* We need wrlock to dup an archive.  */
+  if (ref->kind == ELF_K_AR)
+    {
+      rwlock_unlock (ref->lock);
+      rwlock_wrlock (ref->lock);
+    }
+    /* Duplicate the descriptor.  */
+  return dup_elf (fildes, cmd, ref);
+}
+
+/* Return a descriptor for the file belonging to FILDES.  */
+Elf *
+elf_begin (int fildes, Elf_Cmd cmd, Elf *ref)
+{
+  Elf *retval;
+
+  if (unlikely (! __libelf_version_initialized))
+    {
+      /* Version wasn't set so far.  */
+      __libelf_seterrno (ELF_E_NO_VERSION);
+      return NULL;
+    }
+
+  if (ref != NULL)
+    /* Make sure the descriptor is not suddenly going away.  */
+    rwlock_rdlock (ref->lock);
+  else if (unlikely (fcntl (fildes, F_GETFD) == -1 && errno == EBADF))
+    {
+      /* We cannot do anything productive without a file descriptor.  */
+      __libelf_seterrno (ELF_E_INVALID_FILE);
+      return NULL;
+    }
+
+  switch (cmd)
+    {
+    case ELF_C_NULL:
+      /* We simply return a NULL pointer.  */
+      retval = NULL;
+      break;
+
+    case ELF_C_READ_MMAP_PRIVATE:
+      /* If we have a reference it must also be opened this way.  */
+      if (unlikely (ref != NULL && ref->cmd != ELF_C_READ_MMAP_PRIVATE))
+	{
+	  __libelf_seterrno (ELF_E_INVALID_CMD);
+	  retval = NULL;
+	  break;
+	}
+      FALLTHROUGH;
+
+    case ELF_C_READ:
+    case ELF_C_READ_MMAP:
+      if (ref != NULL)
+	retval = lock_dup_elf (fildes, cmd, ref);
+      else
+	/* Create descriptor for existing file.  */
+	retval = read_file (fildes, 0, ~((size_t) 0), cmd, NULL);
+      break;
+
+    case ELF_C_RDWR:
+    case ELF_C_RDWR_MMAP:
+      /* If we have a REF object it must also be opened using this
+	 command.  */
+      if (ref != NULL)
+	{
+	  if (unlikely (ref->cmd != ELF_C_RDWR && ref->cmd != ELF_C_RDWR_MMAP
+			&& ref->cmd != ELF_C_WRITE
+			&& ref->cmd != ELF_C_WRITE_MMAP))
+	    {
+	      /* This is not ok.  REF must also be opened for writing.  */
+	      __libelf_seterrno (ELF_E_INVALID_CMD);
+	      retval = NULL;
+	    }
+	  else
+	    retval = lock_dup_elf (fildes, cmd, ref);
+	}
+      else
+	/* Create descriptor for existing file.  */
+	retval = read_file (fildes, 0, ~((size_t) 0), cmd, NULL);
+      break;
+
+    case ELF_C_WRITE:
+    case ELF_C_WRITE_MMAP:
+      /* We ignore REF and prepare a descriptor to write a new file.  */
+      retval = write_file (fildes, cmd);
+      break;
+
+    default:
+      __libelf_seterrno (ELF_E_INVALID_CMD);
+      retval = NULL;
+      break;
+    }
+
+  /* Release the lock.  */
+  if (ref != NULL)
+    rwlock_unlock (ref->lock);
+
+  return retval;
+}
+INTDEF(elf_begin)