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/*
 * Copyright (c) 2007-2008 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
#ifndef _KXLD_RELOC_H
#define _KXLD_RELOC_H

#include <mach/machine.h>
#include <sys/types.h>
#if KERNEL
    #include <libkern/kxld_types.h>
#else
    #include "kxld_types.h"
#endif

struct kxld_array;
struct kxld_dict;
struct kxld_sect;
struct kxld_seg;
struct kxld_sym;
struct kxld_symtab;
struct kxld_vtable;
struct relocation_info;

typedef struct kxld_relocator KXLDRelocator;
typedef struct kxld_reloc KXLDReloc;

typedef boolean_t (*RelocHasPair)(u_int r_type);
typedef u_int (*RelocGetPairType)(u_int prev_r_type);
typedef boolean_t (*RelocHasGot)(u_int r_type);
typedef kern_return_t (*ProcessReloc)(const KXLDRelocator *relocator,
    u_char *instruction, u_int length, u_int pcrel, kxld_addr_t base_pc,
    kxld_addr_t link_pc, kxld_addr_t link_disp, u_int type,
    kxld_addr_t target, kxld_addr_t pair_target, boolean_t swap);

struct kxld_relocator {
	RelocHasPair reloc_has_pair;
	RelocGetPairType reloc_get_pair_type;
	RelocHasGot reloc_has_got;
	ProcessReloc process_reloc;
	const struct kxld_symtab *symtab;
	const struct kxld_array *sectarray;
	const struct kxld_dict *vtables;
	const struct kxld_vtable *current_vtable;
	u_char *file;
	u_int function_align; /* Power of two alignment of functions */
	boolean_t is_32_bit;
	boolean_t swap;
	boolean_t may_scatter;
};

struct kxld_reloc {
	u_int address;
	u_int pair_address;
	u_int target;
	u_int pair_target;
	u_int target_type:3;
	u_int pair_target_type:3;
	u_int reloc_type:4;
	u_int length:2;
	u_int pcrel:1;
};

/*******************************************************************************
* Constructors and Destructors
*******************************************************************************/
kern_return_t kxld_relocator_init(KXLDRelocator *relocator, u_char *file,
    const struct kxld_symtab *symtab, const struct kxld_array *sectarray,
    cpu_type_t cputype, cpu_subtype_t cpusubtype, boolean_t swap)
__attribute__((nonnull, visibility("hidden")));

kern_return_t kxld_reloc_create_macho(struct kxld_array *relocarray,
    const KXLDRelocator *relocator, const struct relocation_info *srcs,
    u_int nsrcs) __attribute__((nonnull, visibility("hidden")));

void kxld_relocator_clear(KXLDRelocator *relocator)
__attribute__((nonnull, visibility("hidden")));

/*******************************************************************************
* Accessors
*******************************************************************************/

boolean_t kxld_relocator_has_pair(const KXLDRelocator *relocator, u_int r_type)
__attribute__((pure, nonnull, visibility("hidden")));

u_int kxld_relocator_get_pair_type(const KXLDRelocator *relocator,
    u_int last_r_type)
__attribute__((pure, nonnull, visibility("hidden")));

boolean_t kxld_relocator_has_got(const KXLDRelocator *relocator, u_int r_type)
__attribute__((pure, nonnull, visibility("hidden")));

kxld_addr_t kxld_relocator_get_pointer_at_addr(const KXLDRelocator *relocator,
    const u_char *data, u_long offset)
__attribute__((pure, nonnull, visibility("hidden")));

struct kxld_sym * kxld_reloc_get_symbol(const KXLDRelocator *relocator,
    const KXLDReloc *reloc, const u_char *data)
__attribute__((pure, nonnull(1, 2), visibility("hidden")));

kern_return_t kxld_reloc_get_reloc_index_by_offset(const struct kxld_array *relocs,
    kxld_size_t offset, u_int *idx)
__attribute__((nonnull, visibility("hidden")));

KXLDReloc * kxld_reloc_get_reloc_by_offset(const struct kxld_array *relocs,
    kxld_addr_t offset)
__attribute__((pure, nonnull, visibility("hidden")));

#if KXLD_PIC_KEXTS
u_long kxld_reloc_get_macho_header_size(void)
__attribute__((pure, visibility("hidden")));

u_long kxld_reloc_get_macho_data_size(const struct kxld_array *locrelocs,
    const struct kxld_array *extrelocs)
__attribute__((pure, nonnull, visibility("hidden")));

kern_return_t kxld_reloc_export_macho(const KXLDRelocator *relocator,
    const struct kxld_array *locrelocs, const struct kxld_array *extrelocs,
    u_char *buf, u_long *header_offset, u_long header_size,
    u_long *data_offset, u_long size)
__attribute__((nonnull, visibility("hidden")));
#endif /* KXLD_PIC_KEXTS */

/*******************************************************************************
* Modifiers
*******************************************************************************/

kern_return_t kxld_reloc_update_symindex(KXLDReloc *reloc, u_int symindex)
__attribute__((nonnull, visibility("hidden")));

void kxld_relocator_set_vtables(KXLDRelocator *relocator,
    const struct kxld_dict *vtables)
__attribute__((nonnull, visibility("hidden")));

kern_return_t kxld_relocator_process_sect_reloc(KXLDRelocator *relocator,
    const KXLDReloc *reloc, const struct kxld_sect *sect)
__attribute__((nonnull, visibility("hidden")));

kern_return_t kxld_relocator_process_table_reloc(KXLDRelocator *relocator,
    const KXLDReloc *reloc,
    const struct kxld_seg *seg,
    kxld_addr_t link_addr)
__attribute__((nonnull, visibility("hidden")));

#endif /* _KXLD_RELOC_H */