Squashed 'third_party/elfutils/' content from commit 555e15e

Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/libelf/elf_readall.c b/libelf/elf_readall.c
new file mode 100644
index 0000000..384d251
--- /dev/null
+++ b/libelf/elf_readall.c
@@ -0,0 +1,152 @@
+/* Read all of the file associated with the descriptor.
+   Copyright (C) 1998-2009, 2015 Red Hat, Inc.
+   This file is part of elfutils.
+   Contributed 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 <errno.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+#include <system.h>
+#include "libelfP.h"
+#include "common.h"
+
+
+static void
+set_address (Elf *elf, size_t offset)
+{
+  if (elf->kind == ELF_K_AR)
+    {
+      Elf *child = elf->state.ar.children;
+
+      while (child != NULL)
+	{
+	  if (child->map_address == NULL)
+	    {
+	      child->map_address = elf->map_address;
+	      child->start_offset -= offset;
+	      if (child->kind == ELF_K_AR)
+		child->state.ar.offset -= offset;
+
+	      set_address (child, offset);
+	    }
+
+	  child = child->next;
+	}
+    }
+}
+
+
+char *
+internal_function
+__libelf_readall (Elf *elf)
+{
+  /* Get the file.  */
+  rwlock_wrlock (elf->lock);
+
+  if (elf->map_address == NULL && unlikely (elf->fildes == -1))
+    {
+      __libelf_seterrno (ELF_E_INVALID_HANDLE);
+      rwlock_unlock (elf->lock);
+      return NULL;
+    }
+
+  /* If the file is not mmap'ed and not previously loaded, do it now.  */
+  if (elf->map_address == NULL)
+    {
+      char *mem = NULL;
+
+      /* If this is an archive and we have derived descriptors get the
+	 locks for all of them.  */
+      libelf_acquire_all (elf);
+
+      if (elf->maximum_size == ~((size_t) 0))
+	{
+	  /* We don't yet know how large the file is.   Determine that now.  */
+	  struct stat st;
+
+	  if (fstat (elf->fildes, &st) < 0)
+	    goto read_error;
+
+	  if (sizeof (size_t) >= sizeof (st.st_size)
+	      || st.st_size <= ~((size_t) 0))
+	    elf->maximum_size = (size_t) st.st_size;
+	  else
+	    {
+	      errno = EOVERFLOW;
+	      goto read_error;
+	    }
+	}
+
+      /* Allocate all the memory we need.  */
+      mem = (char *) malloc (elf->maximum_size);
+      if (mem != NULL)
+	{
+	  /* Read the file content.  */
+	  if (unlikely ((size_t) pread_retry (elf->fildes, mem,
+					      elf->maximum_size,
+					      elf->start_offset)
+			!= elf->maximum_size))
+	    {
+	      /* Something went wrong.  */
+	    read_error:
+	      __libelf_seterrno (ELF_E_READ_ERROR);
+	      free (mem);
+	    }
+	  else
+	    {
+	      /* Remember the address.  */
+	      elf->map_address = mem;
+
+	      /* Also remember that we allocated the memory.  */
+	      elf->flags |= ELF_F_MALLOCED;
+
+	      /* Propagate the information down to all children and
+		 their children.  */
+	      set_address (elf, elf->start_offset);
+
+	      /* Correct the own offsets.  */
+	      if (elf->kind == ELF_K_AR)
+		elf->state.ar.offset -= elf->start_offset;
+	      elf->start_offset = 0;
+	    }
+	}
+      else
+	__libelf_seterrno (ELF_E_NOMEM);
+
+      /* Free the locks on the children.  */
+      libelf_release_all (elf);
+    }
+
+  rwlock_unlock (elf->lock);
+
+  return (char *) elf->map_address;
+}