Export elfutils headers and lose the version number from the path.

Having the version number in the path just means that diffs for updates
are completely unusable.

perf refers to libdw.h, libdwfl.h, and version.h as <elfutils/libdw.h> and
so on, so we do still need to do some manual work there, but let's use
symlinks rather than duplicating the header files.

Change-Id: I9fd3c5f5024bde12747fdb1c06d21cdcb3418f03

1 files changed, 220 insertions, 0 deletions

diff --git a/src/libdw/dwarf_nextcu.c b/src/libdw/dwarf_nextcu.c
new file mode 100644
index 00000000..2e8f4d79
--- /dev/null
+++ b/src/libdw/dwarf_nextcu.c
@@ -0,0 +1,220 @@
+/* Advance to next CU header.
+   Copyright (C) 2002-2010 Red Hat, Inc.
+   This file is part of Red Hat elfutils.
+   Written by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+   Red Hat elfutils is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by the
+   Free Software Foundation; version 2 of the License.
+
+   Red Hat 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 a copy of the GNU General Public License along
+   with Red Hat elfutils; if not, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
+
+   In addition, as a special exception, Red Hat, Inc. gives You the
+   additional right to link the code of Red Hat elfutils with code licensed
+   under any Open Source Initiative certified open source license
+   (http://www.opensource.org/licenses/index.php) which requires the
+   distribution of source code with any binary distribution and to
+   distribute linked combinations of the two.  Non-GPL Code permitted under
+   this exception must only link to the code of Red Hat elfutils through
+   those well defined interfaces identified in the file named EXCEPTION
+   found in the source code files (the "Approved Interfaces").  The files
+   of Non-GPL Code may instantiate templates or use macros or inline
+   functions from the Approved Interfaces without causing the resulting
+   work to be covered by the GNU General Public License.  Only Red Hat,
+   Inc. may make changes or additions to the list of Approved Interfaces.
+   Red Hat's grant of this exception is conditioned upon your not adding
+   any new exceptions.  If you wish to add a new Approved Interface or
+   exception, please contact Red Hat.  You must obey the GNU General Public
+   License in all respects for all of the Red Hat elfutils code and other
+   code used in conjunction with Red Hat elfutils except the Non-GPL Code
+   covered by this exception.  If you modify this file, you may extend this
+   exception to your version of the file, but you are not obligated to do
+   so.  If you do not wish to provide this exception without modification,
+   you must delete this exception statement from your version and license
+   this file solely under the GPL without exception.
+
+   Red Hat elfutils is an included package of the Open Invention Network.
+   An included package of the Open Invention Network is a package for which
+   Open Invention Network licensees cross-license their patents.  No patent
+   license is granted, either expressly or impliedly, by designation as an
+   included package.  Should you wish to participate in the Open Invention
+   Network licensing program, please visit www.openinventionnetwork.com
+   <http://www.openinventionnetwork.com>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <libdwP.h>
+#include <dwarf.h>
+
+
+int
+dwarf_next_unit (dwarf, off, next_off, header_sizep, versionp, abbrev_offsetp,
+		 address_sizep, offset_sizep, type_signaturep, type_offsetp)
+     Dwarf *dwarf;
+     Dwarf_Off off;
+     Dwarf_Off *next_off;
+     size_t *header_sizep;
+     Dwarf_Half *versionp;
+     Dwarf_Off *abbrev_offsetp;
+     uint8_t *address_sizep;
+     uint8_t *offset_sizep;
+     uint64_t *type_signaturep;
+     Dwarf_Off *type_offsetp;
+{
+  const bool debug_types = type_signaturep != NULL;
+  const size_t sec_idx = debug_types ? IDX_debug_types : IDX_debug_info;
+
+  /* Maybe there has been an error before.  */
+  if (dwarf == NULL)
+    return -1;
+
+  /* If we reached the end before don't do anything.  */
+  if (off == (Dwarf_Off) -1l
+      || unlikely (dwarf->sectiondata[sec_idx] == NULL)
+      /* Make sure there is enough space in the .debug_info section
+	 for at least the initial word.  We cannot test the rest since
+	 we don't know yet whether this is a 64-bit object or not.  */
+      || unlikely (off + 4 >= dwarf->sectiondata[sec_idx]->d_size))
+    {
+      *next_off = (Dwarf_Off) -1l;
+      return 1;
+    }
+
+  /* This points into the .debug_info section to the beginning of the
+     CU entry.  */
+  const unsigned char *data = dwarf->sectiondata[sec_idx]->d_buf;
+  const unsigned char *bytes = data + off;
+
+  /* The format of the CU header is described in dwarf2p1 7.5.1:
+
+     1.  A 4-byte or 12-byte unsigned integer representing the length
+	 of the .debug_info contribution for that compilation unit, not
+	 including the length field itself. In the 32-bit DWARF format,
+	 this is a 4-byte unsigned integer (which must be less than
+	 0xfffffff0); in the 64-bit DWARF format, this consists of the
+	 4-byte value 0xffffffff followed by an 8-byte unsigned integer
+	 that gives the actual length (see Section 7.2.2).
+
+      2. A 2-byte unsigned integer representing the version of the
+	 DWARF information for that compilation unit. For DWARF Version
+	 2.1, the value in this field is 2.
+
+      3. A 4-byte or 8-byte unsigned offset into the .debug_abbrev
+	 section. This offset associates the compilation unit with a
+	 particular set of debugging information entry abbreviations. In
+	 the 32-bit DWARF format, this is a 4-byte unsigned length; in
+	 the 64-bit DWARF format, this is an 8-byte unsigned length (see
+	 Section 7.4).
+
+      4. A 1-byte unsigned integer representing the size in bytes of
+	 an address on the target architecture. If the system uses
+	 segmented addressing, this value represents the size of the
+	 offset portion of an address.  */
+  uint64_t length = read_4ubyte_unaligned_inc (dwarf, bytes);
+  size_t offset_size = 4;
+  /* Lengths of 0xfffffff0 - 0xffffffff are escape codes.  Oxffffffff is
+     used to indicate that 64-bit dwarf information is being used, the
+     other values are currently reserved.  */
+  if (length == DWARF3_LENGTH_64_BIT)
+    offset_size = 8;
+  else if (unlikely (length >= DWARF3_LENGTH_MIN_ESCAPE_CODE
+		     && length <= DWARF3_LENGTH_MAX_ESCAPE_CODE))
+    {
+    invalid:
+      __libdw_seterrno (DWARF_E_INVALID_DWARF);
+      return -1;
+    }
+
+  /* Now we know how large the header is.  */
+  if (unlikely (DIE_OFFSET_FROM_CU_OFFSET (off, offset_size, debug_types)
+		>= dwarf->sectiondata[sec_idx]->d_size))
+    {
+      *next_off = -1;
+      return 1;
+    }
+
+  if (length == DWARF3_LENGTH_64_BIT)
+    /* This is a 64-bit DWARF format.  */
+    length = read_8ubyte_unaligned_inc (dwarf, bytes);
+
+  /* Read the version stamp.  Always a 16-bit value.  */
+  uint_fast16_t version = read_2ubyte_unaligned_inc (dwarf, bytes);
+
+  /* Get offset in .debug_abbrev.  Note that the size of the entry
+     depends on whether this is a 32-bit or 64-bit DWARF definition.  */
+  uint64_t abbrev_offset;
+  if (__libdw_read_offset_inc (dwarf, sec_idx, &bytes, offset_size,
+			       &abbrev_offset, IDX_debug_abbrev, 0))
+    return -1;
+
+  /* The address size.  Always an 8-bit value.  */
+  uint8_t address_size = *bytes++;
+
+  if (debug_types)
+    {
+      uint64_t type_sig8 = read_8ubyte_unaligned_inc (dwarf, bytes);
+
+      Dwarf_Off type_offset;
+      if (__libdw_read_offset_inc (dwarf, sec_idx, &bytes, offset_size,
+				   &type_offset, sec_idx, 0))
+	return -1;
+
+      /* Validate that the TYPE_OFFSET points past the header.  */
+      if (unlikely (type_offset < (size_t) (bytes - (data + off))))
+	goto invalid;
+
+      *type_signaturep = type_sig8;
+      if (type_offsetp != NULL)
+	*type_offsetp = type_offset;
+    }
+
+  /* Store the header length.  */
+  if (header_sizep != NULL)
+    *header_sizep = bytes - (data + off);
+
+  if (versionp != NULL)
+    *versionp = version;
+
+  if (abbrev_offsetp != NULL)
+    *abbrev_offsetp = abbrev_offset;
+
+  if (address_sizep != NULL)
+    *address_sizep = address_size;
+
+  /* Store the offset size.  */
+  if (offset_sizep != NULL)
+    *offset_sizep = offset_size;
+
+  /* See definition of DIE_OFFSET_FROM_CU_OFFSET macro
+     for an explanation of the trick in this expression.  */
+  *next_off = off + 2 * offset_size - 4 + length;
+
+  return 0;
+}
+INTDEF(dwarf_next_unit)
+
+int
+dwarf_nextcu (dwarf, off, next_off, header_sizep, abbrev_offsetp,
+	      address_sizep, offset_sizep)
+     Dwarf *dwarf;
+     Dwarf_Off off;
+     Dwarf_Off *next_off;
+     size_t *header_sizep;
+     Dwarf_Off *abbrev_offsetp;
+     uint8_t *address_sizep;
+     uint8_t *offset_sizep;
+{
+  return INTUSE(dwarf_next_unit) (dwarf, off, next_off, header_sizep, NULL,
+				  abbrev_offsetp, address_sizep, offset_sizep,
+				  NULL, NULL);
+}
+INTDEF(dwarf_nextcu)