gems-kernel/source/THIRDPARTY/xnu/libkern/kxld/kxld_sym.c

/*
 * Copyright (c) 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@
 */
#include <string.h>
#include <stdint.h>
#include <sys/types.h>
#include <mach-o/nlist.h>
#include <mach-o/stab.h>

#define DEBUG_ASSERT_COMPONENT_NAME_STRING "kxld"
#include <AssertMacros.h>

#include "kxld_sect.h"
#include "kxld_sym.h"
#include "kxld_util.h"

#define CXX_PREFIX                      "__Z"
#define VTABLE_PREFIX                   CXX_PREFIX "TV"
#define OSOBJ_PREFIX                    CXX_PREFIX "N"
#define RESERVED_TOKEN                  "_RESERVED"
#define METACLASS_TOKEN                 "10gMetaClassE"
#define SUPER_METACLASS_POINTER_TOKEN   "10superClassE"
#define METACLASS_VTABLE_PREFIX         VTABLE_PREFIX "N"
#define METACLASS_VTABLE_SUFFIX         "9MetaClassE"
#define CXX_PURE_VIRTUAL                "___cxa_pure_virtual"
#define FINAL_CLASS_TOKEN               "14__OSFinalClassEv"

/*******************************************************************************
* Prototypes
*******************************************************************************/

static kern_return_t init_predicates(KXLDSym *sym, u_char n_type, u_short n_desc)
__attribute__((nonnull));
static void init_sym_sectnum(KXLDSym *sym, u_int n_sect)
__attribute__((nonnull));
static kern_return_t extract_inner_string(const char *str, const char *prefix,
    const char *suffix, char *buf, u_long len);

#if KXLD_USER_OR_ILP32
/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_init_from_macho32(KXLDSym *sym, char *strtab, const struct nlist *src)
{
	kern_return_t rval = KERN_FAILURE;

	check(sym);
	check(strtab);
	check(src);

	bzero(sym, sizeof(*sym));
	sym->name = strtab + src->n_un.n_strx;
	sym->type = src->n_type;
	sym->desc = src->n_desc;
	sym->base_addr = src->n_value;
	sym->link_addr = sym->base_addr;

	rval = init_predicates(sym, src->n_type, src->n_desc);
	require_noerr(rval, finish);

	(void) init_sym_sectnum(sym, src->n_sect);

	if (kxld_sym_is_indirect(sym)) {
		sym->alias = strtab + src->n_value;
	}

	rval = KERN_SUCCESS;

finish:
	return rval;
}
#endif /* KXLD_USER_OR_ILP32 */

#if KXLD_USER_OR_LP64
/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_init_from_macho64(KXLDSym *sym, char *strtab, const struct nlist_64 *src)
{
	kern_return_t rval = KERN_FAILURE;

	check(sym);
	check(strtab);
	check(src);

	bzero(sym, sizeof(*sym));
	sym->name = strtab + src->n_un.n_strx;
	sym->type = src->n_type;
	sym->desc = src->n_desc;
	sym->base_addr = src->n_value;
	sym->link_addr = sym->base_addr;

	if (!strcmp("__ZN15OSMetaClassBase25_RESERVEDOSMetaClassBase3Ev", sym->name)) {
		sym->name = (char *)(uintptr_t) "__ZN15OSMetaClassBase8DispatchE5IORPC";
	}

	rval = init_predicates(sym, src->n_type, src->n_desc);
	require_noerr(rval, finish);

	(void) init_sym_sectnum(sym, src->n_sect);

	if (kxld_sym_is_indirect(sym)) {
		sym->alias = strtab + src->n_value;
	}

	rval = KERN_SUCCESS;

finish:
	return rval;
}
#endif /* KXLD_USER_OR_LP64 */

/*******************************************************************************
*******************************************************************************/
void
kxld_sym_init_absolute(KXLDSym *sym, char *name, kxld_addr_t link_addr)
{
	check(sym);
	check(name);

	bzero(sym, sizeof(*sym));

	sym->name = name;
	sym->link_addr = link_addr;
	sym->type = N_ABS | N_EXT;
	sym->sectnum = NO_SECT;

	init_predicates(sym, N_ABS | N_EXT, 0);
	sym->is_resolved = TRUE;
}

/*******************************************************************************
*******************************************************************************/
static kern_return_t
init_predicates(KXLDSym *sym, u_char n_type, u_short n_desc)
{
	kern_return_t rval = KERN_FAILURE;

	check(sym);

	/* The type field is interpreted differently for normal symbols and stabs */
	if (n_type & N_STAB) {
		sym->is_stab = 1;

		switch (n_type) {
		/* Labeled as NO_SECT in stab.h */
		case N_GSYM:
		case N_FNAME:
		case N_RSYM:
		case N_SSYM:
		case N_LSYM:
		case N_BINCL:
		case N_PARAMS:
		case N_VERSION:
		case N_OLEVEL:
		case N_PSYM:
		case N_EINCL:
		case N_EXCL:
		case N_BCOMM:
		case N_LENG:
		case N_OPT:
		case N_OSO:
			sym->is_absolute = 1;
			break;
		/* Labeled as n_sect in stab.h */
		case N_FUN:
		case N_STSYM:
		case N_LCSYM:
		case N_BNSYM:
		case N_SLINE:
		case N_ENSYM:
		case N_SO:
		case N_SOL:
		case N_ENTRY:
		case N_ECOMM:
		case N_ECOML:
		/* These are labeled as NO_SECT in stab.h, but they are actually
		 * section-based on OS X.  We must mark them as such so they get
		 * relocated.
		 */
		case N_RBRAC:
		case N_LBRAC:
			sym->is_section = 1;
			break;
		default:
			rval = KERN_FAILURE;
			kxld_log(kKxldLogLinking, kKxldLogErr, kKxldLogMalformedMachO
			    "Invalid N_STAB symbol type: %u.", n_type);
			goto finish;
		}

		/* Don't care about the C++ predicates for stabs */
	} else {
		u_char type = n_type & N_TYPE;

		/* The first set of type fields are mutually exclusive, so they can be
		 * set with a switch statement.
		 */
		switch (type) {
		case N_ABS:
			sym->is_absolute = 1;
			break;
		case N_SECT:
			sym->is_section = 1;
			break;
		case N_UNDF:
			if (sym->base_addr) {
				sym->is_common = 1;
			} else {
				sym->is_undefined = 1;
			}
			break;
		case N_INDR:
			sym->is_indirect = 1;
			break;
		default:
			rval = KERN_FAILURE;
			kxld_log(kKxldLogLinking, kKxldLogErr, kKxldLogMalformedMachO
			    "Invalid symbol type: %u.", type);
			goto finish;
		}

		/* Set the type-independent fields */
		if ((n_type & N_EXT) && !(n_type & N_PEXT)) {
			sym->is_external = 1;
		}

		if (n_desc & N_DESC_DISCARDED) {
			sym->is_obsolete = 1;
		}

		if (n_desc & N_WEAK_REF) {
			sym->is_weak = 1;
		}

		if (n_desc & N_ARM_THUMB_DEF) {
			sym->is_thumb = 1;
			sym->base_addr |= 1;
			sym->link_addr |= 1;
		}

		/* Set the C++-specific fields */
		if (!strncmp(CXX_PREFIX, sym->name, const_strlen(CXX_PREFIX))) {
			sym->is_cxx = 1;

			if (streq_safe(sym->name, METACLASS_VTABLE_PREFIX,
			    const_strlen(METACLASS_VTABLE_PREFIX))) {
				sym->is_meta_vtable = 1;
			} else if (streq_safe(sym->name, VTABLE_PREFIX,
			    const_strlen(VTABLE_PREFIX))) {
				sym->is_class_vtable = 1;
			} else if (strnstr(sym->name, RESERVED_TOKEN, strlen(sym->name))) {
				sym->is_padslot = 1;
			} else if (strnstr(sym->name, METACLASS_TOKEN, strlen(sym->name))) {
				sym->is_metaclass = 1;
			} else if (strnstr(sym->name, SUPER_METACLASS_POINTER_TOKEN, strlen(sym->name))) {
				sym->is_super_metaclass_pointer = 1;
			}
		} else if (kxld_sym_name_is_pure_virtual(sym->name)) {
			sym->is_cxx = 1;
			sym->is_pure_virtual = 1;
		}
	}

	rval = KERN_SUCCESS;

finish:
	return rval;
}

/*******************************************************************************
*******************************************************************************/
static void
init_sym_sectnum(KXLDSym *sym, u_int n_sect)
{
	/* The n_sect field is set to 0 when the symbol is not section-based, and
	 * the number of the section in which the symbol exists otherwise.
	 * Sometimes, symbols can be labeled as section-based, so we make sure that
	 * they have a valid section number, and set them as absolute if they don't.
	 */

	if (kxld_sym_is_section(sym)) {
		if (n_sect) {
			/* Convert the section number to an index into the section index */
			sym->sectnum = n_sect - 1;
		} else {
			sym->is_absolute = 1;
			sym->is_section = 0;
		}
	}
}

/*******************************************************************************
*******************************************************************************/
void
kxld_sym_deinit(KXLDSym *sym __unused)
{
	check(sym);
}

/*******************************************************************************
*******************************************************************************/
void
kxld_sym_destroy(KXLDSym *sym)
{
	check(sym);
	kxld_sym_deinit(sym);
	kxld_free(sym, sizeof(*sym));
}


/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_absolute(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_absolute;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_section(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_section;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_defined(const KXLDSym *sym)
{
	check(sym);

	return (kxld_sym_is_absolute(sym) || kxld_sym_is_section(sym)) &&
	       !kxld_sym_is_replaced(sym);
}


/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_defined_locally(const KXLDSym *sym)
{
	check(sym);

	return kxld_sym_is_defined(sym) && !sym->is_resolved;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_external(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_external;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_exported(const KXLDSym *sym)
{
	check(sym);

	return kxld_sym_is_defined_locally(sym) && kxld_sym_is_external(sym);
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_undefined(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_undefined;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_indirect(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_indirect;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_replaced(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_replaced;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_common(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_common;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_unresolved(const KXLDSym *sym)
{
	return (kxld_sym_is_undefined(sym) && !kxld_sym_is_replaced(sym)) ||
	       kxld_sym_is_indirect(sym) || kxld_sym_is_common(sym);
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_obsolete(const KXLDSym *sym)
{
	return 0 != sym->is_obsolete;
}

#if KXLD_USER_OR_GOT
/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_got(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_got;
}
#endif /* KXLD_USER_OR_GOT */

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_stab(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_stab;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_weak(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_weak;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_cxx(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_cxx;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_pure_virtual(const KXLDSym *sym)
{
	return 0 != sym->is_pure_virtual;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_vtable(const KXLDSym *sym)
{
	check(sym);

	return kxld_sym_is_class_vtable(sym) || kxld_sym_is_metaclass_vtable(sym);
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_class_vtable(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_class_vtable;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_metaclass_vtable(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_meta_vtable;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_padslot(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_padslot;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_metaclass(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_metaclass;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_is_super_metaclass_pointer(const KXLDSym *sym)
{
	check(sym);

	return 0 != sym->is_super_metaclass_pointer;
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_name_is_pure_virtual(const char *name)
{
	return streq_safe(CXX_PURE_VIRTUAL, name, sizeof(CXX_PURE_VIRTUAL));
}

/*******************************************************************************
*******************************************************************************/
boolean_t
kxld_sym_name_is_padslot(const char *name)
{
	check(name);

	return strnstr(name, RESERVED_TOKEN, strlen(name)) != 0;
}

/*******************************************************************************
*******************************************************************************/
u_int
kxld_sym_get_section_offset(const KXLDSym *sym, const KXLDSect *sect)
{
	check(sym);

	return (u_int) (sym->base_addr - sect->base_addr);
}

#if KXLD_USER_OR_COMMON
/*******************************************************************************
*******************************************************************************/
kxld_size_t
kxld_sym_get_common_size(const KXLDSym *sym)
{
	return sym->base_addr;
}

/*******************************************************************************
*******************************************************************************/
u_int
kxld_sym_get_common_align(const KXLDSym *sym)
{
	u_int align = GET_COMM_ALIGN(sym->desc);
	if (!align) {
		align = 3;
	}

	return align;
}
#endif /* KXLD_USER_OR_COMMON */

/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_get_class_name_from_metaclass(const KXLDSym *sym,
    char class_name[], u_long class_name_len)
{
	kern_return_t rval = KERN_FAILURE;

	check(sym);
	require_action(kxld_sym_is_metaclass(sym), finish, rval = KERN_FAILURE);

	rval = extract_inner_string(sym->name, OSOBJ_PREFIX, METACLASS_TOKEN,
	    class_name, class_name_len);
	require_noerr(rval, finish);

	rval = KERN_SUCCESS;
finish:
	return rval;
}

/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_get_class_name_from_super_metaclass_pointer(const KXLDSym *sym,
    char class_name[], u_long class_name_len)
{
	kern_return_t rval = KERN_FAILURE;

	check(sym);
	require_action(kxld_sym_is_super_metaclass_pointer(sym), finish,
	    rval = KERN_FAILURE);

	rval = extract_inner_string(sym->name, OSOBJ_PREFIX,
	    SUPER_METACLASS_POINTER_TOKEN, class_name, class_name_len);
	require_noerr(rval, finish);

	rval = KERN_SUCCESS;
finish:
	return rval;
}

/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_get_class_name_from_vtable(const KXLDSym *sym,
    char class_name[], u_long class_name_len)
{
	kern_return_t rval = KERN_FAILURE;

	check(sym);
	require_action(kxld_sym_is_class_vtable(sym), finish, rval = KERN_FAILURE);

	rval = kxld_sym_get_class_name_from_vtable_name(sym->name,
	    class_name, class_name_len);
	require_noerr(rval, finish);

	rval = KERN_SUCCESS;

finish:
	return rval;
}

/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_get_class_name_from_vtable_name(const char *vtable_name,
    char class_name[], u_long class_name_len)
{
	kern_return_t rval = KERN_FAILURE;

	check(vtable_name);

	rval = extract_inner_string(vtable_name, VTABLE_PREFIX, NULL,
	    class_name, class_name_len);
	require_noerr(rval, finish);

	rval = KERN_SUCCESS;
finish:
	return rval;
}

/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_get_vtable_name_from_class_name(const char *class_name,
    char vtable_name[], u_long vtable_name_len)
{
	kern_return_t rval = KERN_FAILURE;
	u_long outlen = 0;

	check(class_name);
	check(vtable_name);

	outlen = strlcpy(vtable_name, VTABLE_PREFIX, vtable_name_len);
	require_action(outlen < vtable_name_len, finish,
	    rval = KERN_FAILURE);

	outlen = strlcat(vtable_name, class_name, vtable_name_len);
	require_action(outlen < vtable_name_len, finish,
	    rval = KERN_FAILURE);

	rval = KERN_SUCCESS;
finish:
	return rval;
}

/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_get_meta_vtable_name_from_class_name(const char *class_name,
    char meta_vtable_name[], u_long meta_vtable_name_len)
{
	kern_return_t rval = KERN_FAILURE;
	u_long outlen = 0;

	check(class_name);
	check(meta_vtable_name);

	outlen = strlcpy(meta_vtable_name, METACLASS_VTABLE_PREFIX,
	    meta_vtable_name_len);
	require_action(outlen < meta_vtable_name_len, finish,
	    rval = KERN_FAILURE);

	outlen = strlcat(meta_vtable_name, class_name, meta_vtable_name_len);
	require_action(outlen < meta_vtable_name_len, finish,
	    rval = KERN_FAILURE);

	outlen = strlcat(meta_vtable_name, METACLASS_VTABLE_SUFFIX,
	    meta_vtable_name_len);
	require_action(outlen < meta_vtable_name_len, finish,
	    rval = KERN_FAILURE);

	rval = KERN_SUCCESS;
finish:
	return rval;
}

/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_get_final_sym_name_from_class_name(const char *class_name,
    char final_sym_name[], u_long final_sym_name_len)
{
	kern_return_t rval = KERN_FAILURE;
	u_long outlen = 0;

	check(class_name);
	check(final_sym_name);

	outlen = strlcpy(final_sym_name, OSOBJ_PREFIX, final_sym_name_len);
	require_action(outlen < final_sym_name_len, finish,
	    rval = KERN_FAILURE);

	outlen = strlcat(final_sym_name, class_name, final_sym_name_len);
	require_action(outlen < final_sym_name_len, finish,
	    rval = KERN_FAILURE);

	outlen = strlcat(final_sym_name, FINAL_CLASS_TOKEN, final_sym_name_len);
	require_action(outlen < final_sym_name_len, finish,
	    rval = KERN_FAILURE);

	rval = KERN_SUCCESS;

finish:
	return rval;
}

/*******************************************************************************
*******************************************************************************/
u_long
kxld_sym_get_function_prefix_from_class_name(const char *class_name,
    char function_prefix[], u_long function_prefix_len)
{
	u_long rval = 0;
	u_long outlen = 0;

	check(class_name);
	check(function_prefix);

	outlen = strlcpy(function_prefix, OSOBJ_PREFIX, function_prefix_len);
	require(outlen < function_prefix_len, finish);

	outlen = strlcat(function_prefix, class_name, function_prefix_len);
	require(outlen < function_prefix_len, finish);

	rval = outlen;
finish:
	return rval;
}

/*******************************************************************************
*******************************************************************************/
static kern_return_t
extract_inner_string(const char *str, const char *prefix, const char *suffix,
    char *buf, u_long len)
{
	kern_return_t rval = KERN_FAILURE;
	u_long prelen = 0, suflen = 0, striplen = 0;

	check(str);
	check(buf);

	prelen = (prefix) ? strlen(prefix) : 0;
	suflen = (suffix) ? strlen(suffix) : 0;
	striplen = strlen(str) - prelen - suflen;

	require_action(striplen < len, finish, rval = KERN_FAILURE);

	strncpy(buf, str + prelen, striplen);
	buf[striplen] = '\0';

	rval = KERN_SUCCESS;
finish:
	return rval;
}

#if KXLD_USER_OR_GOT
/*******************************************************************************
*******************************************************************************/
void
kxld_sym_set_got(KXLDSym *sym)
{
	sym->is_got = 1;
}
#endif /* KXLD_USER_OR_GOT */

/*******************************************************************************
*******************************************************************************/
void
kxld_sym_relocate(KXLDSym *sym, const KXLDSect *sect)
{
	if (kxld_sym_is_section(sym)) {
		sym->link_addr = sym->base_addr - sect->base_addr + sect->link_addr;
		sym->relocated_sectnum = sect->sectnum;
	}
}

#if KXLD_USER_OR_ILP32
/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_export_macho_32(const KXLDSym *sym, u_char *_nl, char *strtab,
    u_long *stroff, u_long strsize)
{
	kern_return_t rval = KERN_FAILURE;
	struct nlist *nl = (struct nlist *) ((void *) _nl);
	char *str = NULL;
	long bytes = 0;

	check(sym);
	check(nl);
	check(strtab);
	check(stroff);

	bytes = strlen(sym->name) + 1;
	require_action((u_long)bytes <= strsize - *stroff, finish,
	    rval = KERN_FAILURE);

	nl->n_type = sym->type;
	nl->n_sect = (kxld_sym_is_section(sym)) ? sym->relocated_sectnum + 1 : 0;
	nl->n_desc = sym->desc;
	nl->n_un.n_strx = (uint32_t) *stroff;
	nl->n_value = (uint32_t) sym->link_addr;
	if (sym->is_thumb) {
		nl->n_value &= ~0x1U;
	}

	str = (char *) (strtab + *stroff);
	strlcpy(str, sym->name, strsize - *stroff);

	*stroff += bytes;
	rval = KERN_SUCCESS;

finish:
	return rval;
}
#endif /* KXLD_USER_OR_ILP32 */

#if KXLD_USER_OR_LP64
/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_export_macho_64(const KXLDSym *sym, u_char *_nl, char *strtab,
    u_long *stroff, u_long strsize)
{
	kern_return_t rval = KERN_FAILURE;
	struct nlist_64 *nl = (struct nlist_64 *) ((void *) _nl);
	char *str = NULL;
	long bytes = 0;

	check(sym);
	check(nl);
	check(strtab);
	check(stroff);

	bytes = strlen(sym->name) + 1;
	require_action((u_long)bytes <= strsize - *stroff, finish,
	    rval = KERN_FAILURE);

	nl->n_type = sym->type;
	nl->n_sect = (kxld_sym_is_section(sym)) ? sym->relocated_sectnum + 1 : 0;
	nl->n_desc = sym->desc;
	nl->n_un.n_strx = (uint32_t) *stroff;
	nl->n_value = (uint64_t) sym->link_addr;
	if (sym->is_thumb) {
		nl->n_value &= ~0x1ULL;
	}

	str = (char *) (strtab + *stroff);

	strlcpy(str, sym->name, strsize - *stroff);

	*stroff += bytes;

	rval = KERN_SUCCESS;

finish:
	return rval;
}
#endif /* KXLD_USER_OR_LP64 */

/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_resolve(KXLDSym *sym, kxld_addr_t addr)
{
	kern_return_t rval = KERN_FAILURE;

	check(sym);

	require_action(kxld_sym_is_undefined(sym) || kxld_sym_is_indirect(sym),
	    finish, rval = KERN_FAILURE);

	/* Set the n_list data types */

	sym->link_addr = addr;
	sym->type = N_ABS | N_EXT;
	sym->sectnum = NO_SECT;

	/* Set the predicate bits for an externally resolved symbol. */

	sym->is_external = TRUE;
	sym->is_absolute = TRUE;
	sym->is_resolved = TRUE;

	/* Clear the predicate bits for types that can be resolved */

	sym->is_undefined = FALSE;
	sym->is_indirect = FALSE;

	rval = KERN_SUCCESS;

finish:

	return rval;
}

#if KXLD_USER_OR_COMMON
/*******************************************************************************
*******************************************************************************/
kern_return_t
kxld_sym_resolve_common(KXLDSym *sym, u_int sectnum, kxld_addr_t base_addr)
{
	kern_return_t rval = KERN_FAILURE;

	check(sym);

	require_action(kxld_sym_is_common(sym), finish,
	    rval = KERN_FAILURE);

	sym->base_addr = base_addr;
	sym->link_addr = base_addr;
	sym->type = N_SECT | N_EXT;
	sym->sectnum = sectnum;
	sym->desc = 0;

	sym->is_absolute = FALSE;
	sym->is_section = TRUE;
	sym->is_undefined = FALSE;
	sym->is_indirect = FALSE;
	sym->is_common = FALSE;
	sym->is_external = TRUE;

	rval = KERN_SUCCESS;

finish:

	return rval;
}
#endif /* KXLD_USER_OR_COMMON */

/*******************************************************************************
*******************************************************************************/
void
kxld_sym_delete(KXLDSym *sym)
{
	check(sym);

	bzero(sym, sizeof(*sym));
	sym->is_replaced = TRUE;
}


/*******************************************************************************
*******************************************************************************/
void
kxld_sym_patch(KXLDSym *sym)
{
	check(sym);

	sym->is_replaced = TRUE;
}

/*******************************************************************************
*******************************************************************************/
void
kxld_sym_mark_private(KXLDSym *sym)
{
	check(sym);

	sym->type |= N_PEXT;
	sym->is_external = FALSE;
}