backends: Add ebl_check_reloc_target_type.

And implement for arm and ia64. Both have special section types that
are valid targets for a reloc. Both refer to unwind data. elflint now
just calls ebl_check_reloc_target_type instead of hard coding the
expected section types.

Signed-off-by: Mark Wielaard <mjw@redhat.com>

6 files changed, 74 insertions, 3 deletions

diff --git a/libebl/ChangeLog b/libebl/ChangeLog
index fc6bdd56..7198d5ec 100644
--- a/libebl/ChangeLog
+++ b/libebl/ChangeLog
@@ -1,3 +1,13 @@
+2014-05-19  Mark Wielaard  <mjw@redhat.com>
+
+	* Makefile.am (gen_SOURCES): Add eblcheckreloctargettype.c.
+	* eblcheckreloctargettype.c: New file.
+	* ebl-hooks.h (check_reloc_target_type): New hook.
+	* eblopenbackend.c (default_check_reloc_target_type): New function.
+	(fill_defaults): Assign default_check_reloc_target_type to
+	check_reloc_target_type.
+	* libebl.h (ebl_check_reloc_target_type): New function definition.
+
 2013-12-18  Mark Wielaard  <mjw@redhat.com>
 
 	* Makefile.am (gen_SOURCES): Add eblresolvesym.c.
diff --git a/libebl/Makefile.am b/libebl/Makefile.am
index 916af72a..ec4477b7 100644
--- a/libebl/Makefile.am
+++ b/libebl/Makefile.am
@@ -55,7 +55,7 @@ gen_SOURCES = eblopenbackend.c eblclosebackend.c eblstrtab.c \
 	      eblsysvhashentrysize.c eblauxvinfo.c eblcheckobjattr.c \
 	      ebl_check_special_section.c ebl_syscall_abi.c eblabicfi.c \
 	      eblstother.c eblinitreg.c ebldwarftoregno.c eblnormalizepc.c \
-	      eblunwind.c eblresolvesym.c
+	      eblunwind.c eblresolvesym.c eblcheckreloctargettype.c
 
 libebl_a_SOURCES = $(gen_SOURCES)
 
diff --git a/libebl/ebl-hooks.h b/libebl/ebl-hooks.h
index bfb7f4a9..65c62ec6 100644
--- a/libebl/ebl-hooks.h
+++ b/libebl/ebl-hooks.h
@@ -1,5 +1,5 @@
 /* Backend hook signatures internal interface for libebl.
-   Copyright (C) 2000-2011, 2013 Red Hat, Inc.
+   Copyright (C) 2000-2011, 2013, 2014 Red Hat, Inc.
    This file is part of elfutils.
 
    This file is free software; you can redistribute it and/or modify
@@ -105,6 +105,9 @@ bool EBLHOOK(object_note) (const char *, uint32_t, uint32_t, const char *);
 bool EBLHOOK(check_object_attribute) (Ebl *, const char *, int, uint64_t,
 				      const char **, const char **);
 
+/* Check reloc target section type.  */
+bool EBLHOOK(check_reloc_target_type) (Ebl *, Elf64_Word);
+
 /* Describe auxv element type.  */
 int EBLHOOK(auxv_info) (GElf_Xword, const char **, const char **);
 
diff --git a/libebl/eblcheckreloctargettype.c b/libebl/eblcheckreloctargettype.c
new file mode 100644
index 00000000..e135f8a3
--- /dev/null
+++ b/libebl/eblcheckreloctargettype.c
@@ -0,0 +1,46 @@
+/* Check whether a section type is a valid target for relocation.
+   Copyright (C) 2014 Red Hat, Inc.
+   This file is part of elfutils.
+
+   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 <libeblP.h>
+
+
+bool
+ebl_check_reloc_target_type (Ebl *ebl, Elf64_Word sh_type)
+{
+  if (ebl->check_reloc_target_type (ebl, sh_type))
+    return true;
+
+  if (sh_type == SHT_PROGBITS || sh_type == SHT_NOBITS)
+    return true;
+
+  return false;
+}
diff --git a/libebl/eblopenbackend.c b/libebl/eblopenbackend.c
index c19ae1b2..bd947599 100644
--- a/libebl/eblopenbackend.c
+++ b/libebl/eblopenbackend.c
@@ -1,5 +1,5 @@
 /* Generate ELF backend handle.
-   Copyright (C) 2000-2013 Red Hat, Inc.
+   Copyright (C) 2000-2014 Red Hat, Inc.
    This file is part of elfutils.
 
    This file is free software; you can redistribute it and/or modify
@@ -200,6 +200,7 @@ static bool default_check_object_attribute (Ebl *ebl, const char *vendor,
 					    int tag, uint64_t value,
 					    const char **tag_name,
 					    const char **value_name);
+static bool default_check_reloc_target_type (Ebl *ebl, Elf64_Word sh_type);
 static int default_abi_cfi (Ebl *ebl, Dwarf_CIE *abi_info);
 
 
@@ -241,6 +242,7 @@ fill_defaults (Ebl *result)
   result->register_info = default_register_info;
   result->syscall_abi = default_syscall_abi;
   result->check_object_attribute = default_check_object_attribute;
+  result->check_reloc_target_type = default_check_reloc_target_type;
   result->disasm = NULL;
   result->abi_cfi = default_abi_cfi;
   result->destr = default_destr;
@@ -747,6 +749,13 @@ default_check_object_attribute (Ebl *ebl __attribute__ ((unused)),
   return false;
 }
 
+static bool
+default_check_reloc_target_type (Ebl *ebl __attribute__ ((unused)),
+				 Elf64_Word sh_type __attribute__ ((unused)))
+{
+  return false;
+}
+
 static int
 default_abi_cfi (Ebl *ebl __attribute__ ((unused)),
 		 Dwarf_CIE *abi_info __attribute__ ((unused)))
diff --git a/libebl/libebl.h b/libebl/libebl.h
index 50d6baab..d05751fa 100644
--- a/libebl/libebl.h
+++ b/libebl/libebl.h
@@ -179,6 +179,9 @@ extern bool ebl_check_object_attribute (Ebl *ebl, const char *vendor,
 					const char **tag_name,
 					const char **value_name);
 
+/* Check whether a section type is a valid reloc target.  */
+extern bool ebl_check_reloc_target_type (Ebl *ebl, Elf64_Word sh_type);
+
 
 /* Check section name for being that of a debug informatino section.  */
 extern bool ebl_debugscn_p (Ebl *ebl, const char *name);