Support .debug_macro

- This code is based on the following proposal:
    http://www.dwarfstd.org/ShowIssue.php?issue=110722.1

- dwarf_getmacros serves either of .debug_macinfo or .debug_macro
  transparently, but if the latter uses opcode 0xff, it bails out with
  an error.  The reason is that in .debug_macro, 0xff is a custom code
  that can mean anything, while in .debug_macinfo there's fixed
  semantics associated with 0xff.

- dwarf_getmacros_off is a new interface used for requesting iteration
  through transparently included units.

- dwarf_macro_getparamcnt and dwarf_macro_param are new interfaces
  used for requesting number of parameters of an opcode and individual
  parameters.  dwarf_macro_getsrcfiles is a new interface used for
  requesting a file part of .debug_line unit associated with macro
  unit that the opcode comes from.

- The existing interfaces dwarf_macro_opcode, dwarf_macro_param1 and
  dwarf_macro_param2 remain operational for old- as well as new-style
  Dwarf macro sections, if applicable.

- dwarf_getsrclines was made into a light wrapper around a worker
  function that loads line unit given its offset.  The worker also
  caches loaded units in an offset-keyed search tree, so that we don't
  end up re-reading units even though they were read in a different
  domain (e.g. a macro unit request can prime cache for later CU
  lookup).  dwarf_macro_getsrcfiles calls the worker function under
  covers.

Signed-off-by: Petr Machata <pmachata@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/libdw/dwarf_error.c b/libdw/dwarf_error.c
index 22929141..08b691aa 100644
--- a/libdw/dwarf_error.c
+++ b/libdw/dwarf_error.c
@@ -1,5 +1,5 @@
 /* Retrieve ELF descriptor used for DWARF access.
-   Copyright (C) 2002, 2003, 2004, 2005, 2009 Red Hat, Inc.
+   Copyright (C) 2002, 2003, 2004, 2005, 2009, 2014 Red Hat, Inc.
    This file is part of elfutils.
    Written by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -92,6 +92,7 @@ static const char *errmsgs[] =
     [DWARF_E_NO_DEBUG_RANGES] = N_(".debug_ranges section missing"),
     [DWARF_E_INVALID_CFI] = N_("invalid CFI section"),
     [DWARF_E_NO_ALT_DEBUGLINK] = N_("no alternative debug link found"),
+    [DWARF_E_INVALID_OPCODE] = N_("invalid opcode"),
   };
 #define nerrmsgs (sizeof (errmsgs) / sizeof (errmsgs[0]))