binutils-gdb/include/elf/reloc-macros.h

130 lines
4.0 KiB
C

/* Generic relocation support for BFD.
Copyright (C) 1998-2017 Free Software Foundation, Inc.
This file is part of BFD, the Binary File Descriptor library.
This program 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; either version 3 of the License, or
(at your option) any later version.
This program 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 this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
/* These macros are used by the various *.h target specific header
files to either generate an enum containing all the known relocations
for that target, or if RELOC_MACROS_GEN_FUNC is defined, a recognition
function is generated instead. (This is used by binutils/readelf.c)
Given a header file like this:
START_RELOC_NUMBERS (foo)
RELOC_NUMBER (R_foo_NONE, 0)
RELOC_NUMBER (R_foo_32, 1)
EMPTY_RELOC (R_foo_good)
FAKE_RELOC (R_foo_illegal, 9)
END_RELOC_NUMBERS (R_foo_count)
Then the following will be produced by default (ie if
RELOC_MACROS_GEN_FUNC is *not* defined).
enum foo
{
R_foo_NONE = 0,
R_foo_32 = 1,
R_foo_good,
R_foo_illegal = 9,
R_foo_count
};
Note: The value of the symbol defined in the END_RELOC_NUMBERS
macro (R_foo_count in the case of the example above) will be
set to the value of the whichever *_RELOC macro precedes it plus
one. Therefore if you intend to use the symbol as a sentinel for
the highest valid macro value you should make sure that the
preceding *_RELOC macro is the highest valid number. ie a
declaration like this:
START_RELOC_NUMBERS (foo)
RELOC_NUMBER (R_foo_NONE, 0)
RELOC_NUMBER (R_foo_32, 1)
FAKE_RELOC (R_foo_illegal, 9)
FAKE_RELOC (R_foo_synonym, 0)
END_RELOC_NUMBERS (R_foo_count)
will result in R_foo_count having a value of 1 (R_foo_synonym + 1)
rather than 10 or 2 as might be expected.
Alternatively you can assign a value to END_RELOC_NUMBERS symbol
explicitly, like this:
START_RELOC_NUMBERS (foo)
RELOC_NUMBER (R_foo_NONE, 0)
RELOC_NUMBER (R_foo_32, 1)
FAKE_RELOC (R_foo_illegal, 9)
FAKE_RELOC (R_foo_synonym, 0)
END_RELOC_NUMBERS (R_foo_count = 2)
If RELOC_MACROS_GEN_FUNC *is* defined, then instead the
following function will be generated:
static const char *foo (unsigned long rtype);
static const char *
foo (unsigned long rtype)
{
switch (rtype)
{
case 0: return "R_foo_NONE";
case 1: return "R_foo_32";
default: return NULL;
}
}
*/
#ifndef _RELOC_MACROS_H
#define _RELOC_MACROS_H
#ifdef RELOC_MACROS_GEN_FUNC
/* This function takes the relocation number and returns the
string version name of the name of that relocation. If
the relocation is not recognised, NULL is returned. */
#define START_RELOC_NUMBERS(name) \
static const char *name (unsigned long rtype); \
static const char * \
name (unsigned long rtype) \
{ \
switch (rtype) \
{
#define RELOC_NUMBER(name, number) \
case number: return #name;
#define FAKE_RELOC(name, number)
#define EMPTY_RELOC(name)
#define END_RELOC_NUMBERS(name) \
default: return NULL; \
} \
}
#else /* Default to generating enum. */
#define START_RELOC_NUMBERS(name) enum name {
#define RELOC_NUMBER(name, number) name = number,
#define FAKE_RELOC(name, number) name = number,
#define EMPTY_RELOC(name) name,
#define END_RELOC_NUMBERS(name) name };
#endif
#endif /* _RELOC_MACROS_H */