Home | History | Annotate | Download | only in common
      1 /*
      2  * CDDL HEADER START
      3  *
      4  * The contents of this file are subject to the terms of the
      5  * Common Development and Distribution License (the "License").
      6  * You may not use this file except in compliance with the License.
      7  *
      8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
      9  * or http://www.opensolaris.org/os/licensing.
     10  * See the License for the specific language governing permissions
     11  * and limitations under the License.
     12  *
     13  * When distributing Covered Code, include this CDDL HEADER in each
     14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
     15  * If applicable, add the following below this CDDL HEADER, with the
     16  * fields enclosed by brackets "[]" replaced with your own identifying
     17  * information: Portions Copyright [yyyy] [name of copyright owner]
     18  *
     19  * CDDL HEADER END
     20  */
     21 
     22 /*
     23  *	Copyright (c) 1988 AT&T
     24  *	  All Rights Reserved
     25  *
     26  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
     27  * Use is subject to license terms.
     28  */
     29 
     30 /*
     31  * Local include file for ld library.
     32  */
     33 
     34 #ifndef	_LIBLD_DOT_H
     35 #define	_LIBLD_DOT_H
     36 
     37 #include <libld.h>
     38 #include <_libelf.h>
     39 #include <debug.h>
     40 #include <conv.h>
     41 #include <msg.h>
     42 #include <reloc_defs.h>
     43 
     44 #ifdef	__cplusplus
     45 extern "C" {
     46 #endif
     47 
     48 /*
     49  * In order to allow for cross linking, we need to be able to build
     50  * libld with support for multiple targets within a single object.
     51  * This is done using a global variable (ld_targ) of type Target to
     52  * access target-specific code for the current target via indirection.
     53  */
     54 
     55 /*
     56  * Machine information for target
     57  */
     58 typedef struct {
     59 	Half		m_mach;		/* ELF machine code for target */
     60 	Half		m_machplus;	/* Alt ELF machine code for target */
     61 					/*	Used for EM_SPARC32PLUS */
     62 	Word		m_flagsplus;	/* ELF header flags used to identify */
     63 					/*	a machplus object */
     64 	uchar_t		m_class;	/* Target ELFCLASS */
     65 	uchar_t		m_data;		/* Target byte order */
     66 
     67 	Xword		m_segm_align;	/* segment alignment */
     68 	Xword		m_segm_origin;	/* Default 1st segment origin */
     69 	Xword		m_segm_aorigin;	/* Alternative 1st segment origin */
     70 	Word		m_dataseg_perm;	/* data segment permission mask */
     71 	Word		m_word_align;	/* alignment to use for Word sections */
     72 	const char	*m_def_interp;	/* Def. interpreter for dyn objects */
     73 
     74 	/* Relocation type codes */
     75 	Word		m_r_arrayaddr;
     76 	Word		m_r_copy;
     77 	Word		m_r_glob_dat;
     78 	Word		m_r_jmp_slot;
     79 	Word		m_r_num;
     80 	Word		m_r_none;
     81 	Word		m_r_relative;
     82 	Word		m_r_register;
     83 
     84 	/* Relocation related constants */
     85 	Word		m_rel_dt_count;	/* Either DT_REL or DT_RELA */
     86 	Word		m_rel_dt_ent;	/* Either DT_RELENT or DT_RELAENT */
     87 	Word		m_rel_dt_size;	/* Either DT_RELSZ or DT_RELASZ */
     88 	Word		m_rel_dt_type;	/* Either DT_RELCOUNT or DT_RELACOUNT */
     89 	Word		m_rel_sht_type;	/* Either SHT_REL or SHT_RELA */
     90 
     91 	/* GOT related constants */
     92 	Word		m_got_entsize;
     93 	Word		m_got_xnumber;	/* reserved # of got ents */
     94 
     95 	/* PLT related constants */
     96 	Word		m_plt_align;
     97 	Word		m_plt_entsize;
     98 	Word		m_plt_reservsz;
     99 	Word		m_plt_shf_flags;
    100 
    101 	/* Section type of .eh_frame/.eh_frame_hdr sections */
    102 	Word		m_sht_unwind;
    103 
    104 	Word		m_dt_register;
    105 } Target_mach;
    106 
    107 
    108 /*
    109  * Section identifiers, used to order sections in output object
    110  */
    111 typedef struct {
    112 	Word		id_array;
    113 	Word		id_bss;
    114 	Word		id_cap;
    115 	Word		id_data;
    116 	Word		id_dynamic;
    117 	Word		id_dynsort;
    118 	Word		id_dynstr;
    119 	Word		id_dynsym;
    120 	Word		id_dynsym_ndx;
    121 	Word		id_got;
    122 	Word		id_gotdata;
    123 	Word		id_hash;
    124 	Word		id_interp;
    125 	Word		id_lbss;
    126 	Word		id_ldynsym;
    127 	Word		id_note;
    128 	Word		id_null;
    129 	Word		id_plt;
    130 	Word		id_rel;
    131 	Word		id_strtab;
    132 	Word		id_syminfo;
    133 	Word		id_symtab;
    134 	Word		id_symtab_ndx;
    135 	Word		id_text;
    136 	Word		id_tls;
    137 	Word		id_tlsbss;
    138 	Word		id_unknown;
    139 	Word		id_unwind;
    140 	Word		id_unwindhdr;
    141 	Word		id_user;
    142 	Word		id_version;
    143 } Target_machid;
    144 
    145 /*
    146  * Target_nullfunc supplies machine code for generating a
    147  *
    148  *	void (*)(void)
    149  *
    150  * unnamed function. Such a function can be called, and returns
    151  * immediately without doing any work. This is used to back FUNC
    152  * symbol definitions added with a mapfile.
    153  *
    154  * The machine instructions are specified as an array of bytes rather
    155  * than a larger integer type in order to avoid byte order issues that
    156  * can otherwise occur in cross linking.
    157  */
    158 typedef struct {
    159 	const uchar_t	*nf_template;	/* Array of machine inst. bytes */
    160 	size_t		nf_size;	/* # bytes in nf_template */
    161 } Target_nullfunc;
    162 
    163 /*
    164  * Target_fill supplies machine code for fill bytes in executable output
    165  * sections. Normally, libelf fills the gaps caused by alignment and size
    166  * requirements of the constituent input sections with 0. Depending on the
    167  * target architecture, it may be desirable to instead fill with executable
    168  * NOP instructions. There are two reasons to do this:
    169  *
    170  * -	So that .init/.fini sections will not contain unexecutable gaps
    171  *	that cause the executing program to trap and die.
    172  *
    173  * -	To eliminate confusing garbage instructions between sections containing
    174  *	executable code when viewed with a dissassembler.
    175  *
    176  * The ff_execfill function is allowed to be NULL if the underlying target
    177  * does not require a special fill for executable sections.
    178  */
    179 typedef struct {
    180 	_elf_execfill_func_t	*ff_execfill;
    181 } Target_fillfunc;
    182 
    183 /*
    184  * Target_machrel holds pointers to the reloc_table and machrel functions
    185  * for a given target machine.
    186  *
    187  * The following function pointers are allowed to be NULL, if the
    188  * underlying target does not require the specified operation. All
    189  * other functions must be supplied:
    190  *
    191  *	mr_assign_got
    192  *	mr_reloc_register
    193  *	mr_reloc_GOTOP
    194  *	mr_allocate_got
    195  */
    196 typedef struct {
    197 	const Rel_entry	*mr_reloc_table;
    198 
    199 	Word		(* mr_init_rel)(Rel_desc *, void *);
    200 	void 		(* mr_mach_eflags)(Ehdr *, Ofl_desc *);
    201 	void		(* mr_mach_make_dynamic)(Ofl_desc *, size_t *);
    202 	void		(* mr_mach_update_odynamic)(Ofl_desc *, Dyn **);
    203 	Xword		(* mr_calc_plt_addr)(Sym_desc *, Ofl_desc *);
    204 	uintptr_t	(* mr_perform_outreloc)(Rel_desc *, Ofl_desc *);
    205 	uintptr_t	(* mr_do_activerelocs)(Ofl_desc *);
    206 	uintptr_t	(* mr_add_outrel)(Word, Rel_desc *, Ofl_desc *);
    207 	uintptr_t	(* mr_reloc_register)(Rel_desc *, Is_desc *,
    208 			    Ofl_desc *);
    209 	uintptr_t	(* mr_reloc_local)(Rel_desc *, Ofl_desc *);
    210 	uintptr_t	(* mr_reloc_GOTOP)(Boolean, Rel_desc *, Ofl_desc *);
    211 	uintptr_t	(* mr_reloc_TLS)(Boolean, Rel_desc *, Ofl_desc *);
    212 	uintptr_t	(* mr_assign_got)(Ofl_desc *, Sym_desc *);
    213 
    214 	Gotndx		*(* mr_find_got_ndx)(Alist *, Gotref, Ofl_desc *,
    215 			    Rel_desc *);
    216 	Xword		(* mr_calc_got_offset)(Rel_desc *, Ofl_desc *);
    217 	uintptr_t	(* mr_assign_got_ndx)(Alist **, Gotndx *, Gotref,
    218 			    Ofl_desc *, Rel_desc *, Sym_desc *);
    219 	void		(* mr_assign_plt_ndx)(Sym_desc *, Ofl_desc *);
    220 	uintptr_t	(* mr_allocate_got)(Ofl_desc *);
    221 	uintptr_t	(* mr_fillin_gotplt)(Ofl_desc *);
    222 } Target_machrel;
    223 
    224 
    225 /*
    226  * Target_machsym holds pointers to the machsym functions
    227  * for a given target machine.
    228  *
    229  * These fields are allowed to be NULL for targets that do not require
    230  * special handling of register symbols. Register symbols are used by
    231  * sparc targets. If any of these fields are non-NULL, all of them are
    232  * required to be present (use empty stub routines if necessary).
    233  */
    234 typedef struct {
    235 	int		(* ms_reg_check)(Sym_desc *, Sym *, const char *,
    236 			    Ifl_desc *, Ofl_desc *);
    237 	int		(* ms_mach_sym_typecheck)(Sym_desc *, Sym *,
    238 			    Ifl_desc *, Ofl_desc *);
    239 	const char	*(* ms_is_regsym)(Ofl_desc *, Ifl_desc *, Sym *,
    240 			    const char *, int, Word, const char *, sd_flag_t *);
    241 	Sym_desc	*(* ms_reg_find)(Sym * sym, Ofl_desc * ofl);
    242 	int		(* ms_reg_enter)(Sym_desc *, Ofl_desc *);
    243 } Target_machsym;
    244 
    245 typedef struct {
    246 	Target_mach	t_m;
    247 	Target_machid	t_id;
    248 	Target_nullfunc	t_nf;
    249 	Target_fillfunc	t_ff;
    250 	Target_machrel	t_mr;
    251 	Target_machsym	t_ms;
    252 } Target;
    253 
    254 /*
    255  * Structure to manage the update of weak symbols from their associated alias.
    256  */
    257 typedef	struct wk_desc {
    258 	Sym		*wk_symtab;	/* the .symtab entry */
    259 	Sym		*wk_dynsym;	/* the .dynsym entry */
    260 	Sym_desc	*wk_weak;	/* the original weak symbol */
    261 	Sym_desc	*wk_alias;	/* the real symbol */
    262 } Wk_desc;
    263 
    264 /*
    265  * Structure to manage the support library interfaces.
    266  */
    267 typedef struct func_list {
    268 	const char	*fl_obj;	/* name of support object */
    269 					/*	function is from */
    270 	void		(*fl_fptr)();	/* function pointer */
    271 	uint_t		fl_version;	/* ld_version() level */
    272 } Func_list;
    273 
    274 typedef	struct support_list {
    275 	const char	*sup_name;	/* ld_support function name */
    276 	Alist		*sup_funcs;	/* list of support functions */
    277 } Support_list;
    278 
    279 /*
    280  * Structure to manage a sorted output relocation list.
    281  *
    282  *	rl_key1		->	pointer to needed ndx
    283  *	rl_key2		->	pointer to symbol relocation is against
    284  *	rl_key3		->	virtual offset of relocation
    285  */
    286 typedef struct reloc_list {
    287 	Sym_desc	*rl_key2;
    288 	Xword		rl_key3;
    289 	Rel_desc	*rl_rsp;
    290 	Half		rl_key1;
    291 } Reloc_list;
    292 
    293 
    294 typedef struct sym_s_list {
    295 	Word		sl_hval;
    296 	Sym_desc	*sl_sdp;
    297 } Sym_s_list;
    298 
    299 /*
    300  * ld heap management structure
    301  */
    302 typedef struct _ld_heap Ld_heap;
    303 struct _ld_heap {
    304 	Ld_heap		*lh_next;
    305 	void		*lh_free;
    306 	void		*lh_end;
    307 };
    308 
    309 #define	HEAPBLOCK	0x800000	/* default allocation block size */
    310 #define	HEAPALIGN	0x8		/* heap blocks alignment requirement */
    311 
    312 /*
    313  * Dynamic per-symbol filtee string table descriptor.  This associates filtee
    314  * strings that will be created in the .dynstr, with .dynamic entries.
    315  */
    316 typedef struct {
    317 	char		*dft_str;	/* dynstr string */
    318 	Word		dft_flag;	/* auxiliary/filtee type */
    319 	Half		dft_ndx;	/* eventual ndx into .dynamic */
    320 } Dfltr_desc;
    321 
    322 /*
    323  * Per-symbol filtee descriptor.  This associates symbol definitions with
    324  * their filtees.
    325  */
    326 typedef struct {
    327 	Sym_desc	*sft_sdp;	/* symbol descriptor */
    328 	Aliste		sft_idx;	/* index into dtstr descriptor */
    329 } Sfltr_desc;
    330 
    331 /*
    332  * Define Alist initialization sizes.
    333  */
    334 #define	AL_CNT_IFL_GROUPS	20	/* ifl_groups */
    335 #define	AL_CNT_IFL_RELSECS	6	/* ifl_relsect */
    336 
    337 #define	AL_CNT_OFL_DTSFLTRS	4	/* ofl_dtsfltrs */
    338 #define	AL_CNT_OFL_SYMFLTRS	20	/* ofl_symfltrs */
    339 #define	AL_CNT_OFL_MAPSECS	10	/* ofl_map{text|data} */
    340 #define	AL_CNT_OFL_OBJS		50	/* ofl_objs */
    341 #define	AL_CNT_OFL_LIBS		10	/* ofl_sos */
    342 #define	AL_CNT_OFL_LIBDIRS	10	/* ofl_[ud]libdirs */
    343 #define	AL_CNT_OFL_MAPFILES	6	/* ofl_maps */
    344 #define	AL_CNT_OFL_ENTRANCE	10	/* ofl_ents */
    345 #define	AL_CNT_OFL_RELS		4	/* ofl_outrels */
    346 #define	AL_CNT_OFL_COPYRELS	10	/* ofl_copyrels */
    347 #define	AL_CNT_OFL_ARRAYS	10	/* ofl_{init|fini|prei}array */
    348 #define	AL_CNT_OFL_OSGROUPS	10	/* ofl_osgroups */
    349 #define	AL_CNT_OFL_OSTLSSEG	4	/* ofl_ostlsseg */
    350 #define	AL_CNT_OFL_ORDERED	4	/* ofl_ordered */
    351 #define	AL_CNT_OFL_SYMINFOSYMS	50	/* ofl_syminfsyms */
    352 #define	AL_CNT_OFL_MOVE		10	/* ofl_ismove */
    353 #define	AL_CNT_OFL_UNWIND	1	/* ofl_unwind */
    354 #define	AL_CNT_OFL_PARSYMS	10	/* ofl_parsyms */
    355 
    356 #define	AL_CNT_OS_MSTRISDESCS	10	/* os_mstrisdescs */
    357 #define	AL_CNT_OS_RELISDESCS	100	/* os_relisdescs */
    358 #define	AL_CNT_OS_COMDATS	20	/* os_comdats */
    359 #define	AL_CNT_OS_ISDESCS_BA	4	/* os_isdesc: BEFORE|AFTER */
    360 #define	AL_CNT_OS_ISDESCS	60	/* os_isdesc: ORDERED|DEFAULT */
    361 
    362 #define	AL_CNT_SG_OSDESC	40	/* sg_osdescs */
    363 #define	AL_CNT_SG_SECORDER	40	/* sg_secorder */
    364 
    365 #define	AL_CNT_SDP_GOT		1	/* sd_GOTndxs */
    366 #define	AL_CNT_SDP_MOVE		1	/* sd_move */
    367 #define	AL_CNT_SDP_DFILES	1	/* sa_dfiles */
    368 
    369 #define	AL_CNT_SDF_VERSIONS	2	/* sdf_{vers|verneed} */
    370 
    371 #define	AL_CNT_EC_FILES		1	/* ec_files */
    372 
    373 #define	AL_CNT_VERDESCS		20	/* version desc */
    374 #define	AL_CNT_WEAK		20	/* weak desc */
    375 #define	AL_CNT_SUPPORT		2	/* support libraries */
    376 #define	AL_CNT_STRMRGREL	500	/* ld_make_strmerge() reloc alist cnt */
    377 #define	AL_CNT_STRMRGSYM	20	/* ld_make_strmerge() sym alist cnt */
    378 #define	AL_CNT_SEGMENTS		20	/* ofl_segs */
    379 
    380 /*
    381  * Return codes for {tls|got}_fixups() routines
    382  */
    383 typedef enum {
    384 	FIX_ERROR,	/* fatal error - time to punt */
    385 	FIX_DONE,	/* relocation done - no further processing required */
    386 	FIX_RELOC	/* do_reloc() relocation processing required */
    387 } Fixupret;
    388 
    389 #ifndef	FILENAME_MAX
    390 #define	FILENAME_MAX	BUFSIZ		/* maximum length of a path name */
    391 #endif
    392 
    393 /*
    394  * We pad the end of the .dynstr section with a block of DYNSTR_EXTRA_PAD
    395  * bytes, and we insert DYNAMIC_EXTRA_ELTS unused items into the
    396  * .dynamic section (with value DT_NULL). This provides the resources needed
    397  * to add and/or alter string items in the .dynamic section, such as runpath.
    398  */
    399 #define	DYNSTR_EXTRA_PAD	512
    400 #define	DYNAMIC_EXTRA_ELTS	10
    401 
    402 /*
    403  * Relocation buckets are sized based on the number of input relocations and
    404  * the following constants.
    405  */
    406 #define	REL_HAIDESCNO	1000		/* high water mark active buckets */
    407 #define	REL_LAIDESCNO	50		/* low water mark active buckets */
    408 #define	REL_HOIDESCNO	500		/* high water mark output buckets */
    409 #define	REL_LOIDESCNO	10		/* low water mark output buckets */
    410 
    411 /*
    412  * Given a symbol of a type that is allowed within a .SUNW_dynsymsort or
    413  * .SUNW_dyntlssort section, examine the symbol attributes to determine
    414  * if this particular symbol should be included or not.
    415  *
    416  * entry:
    417  *	The symbol must have an allowed type: Either a type verified by
    418  *	dynsymsort_symtype[] or STT_TLS.
    419  *
    420  *	_sdp - Pointer to symbol descriptor
    421  *	_sym - Pointer to symbol referenced by _sdp.
    422  *
    423  *	_sym is derivable from _sdp: _sdp->sd_sym
    424  *	However, most callers assign it to a local variable for efficiency,
    425  *	and this macro allows such a variable to be used within. If you
    426  *	don't have such a variable, supply _sdp->sd_sym.
    427  *
    428  * The tests used require some explanation:
    429  *
    430  *	(_sdp->sd_flags & FLG_SY_DYNSORT)
    431  *		Some special symbols are kept even if they don't meet the
    432  *		usual requirements. These symbols have the FLG_SY_DYNSORT
    433  *		bit set. If this bit isn't set then we look at the other
    434  *		attributes.
    435  *
    436  *	(((_sdp->sd_ref != REF_DYN_NEED) &&
    437  *		(_sdp->sd_sym->st_shndx != SHN_UNDEF))
    438  *	|| (_sdp->sd_flags & FLG_SY_MVTOCOMM))
    439  *		We do not want to include symbols that are not defined within
    440  *		the object we are creating. REF_DYN_NEED corresponds to those
    441  *		UNDEF items. However, if the symbol is the target of a copy
    442  *		relocation, then it effectively becomes defined within the
    443  *		object after all. FLG_SY_MVTOCOMM indicates a copy relocation,
    444  *		and prevents us from culling those exceptions.
    445  *
    446  *	(_sym->st_size != 0)
    447  *		Symbols with 0 length are labels injected by the compilers
    448  *		or the linker for purposes of code generation, and do
    449  *		not directly correspond to actual code. In fact, most of the
    450  *		symbols we mark with FLG_SY_DYNSORT need that flag set because
    451  *		they have size 0. This size test filters out the others.
    452  *
    453  *	!(_sdp->sd_flags & FLG_SY_NODYNSORT)
    454  *		Some symbols are not kept, even though they do meet the usual
    455  *		requirements. These symbols have FLG_SY_NODYNSORT set.
    456  *		For example, if there are weak and non-weak versions of a given
    457  *		symbol, we only want to keep one of them. So, we set
    458  *		FLG_SY_NODYNSORT on the one we don't want.
    459  */
    460 #define	DYNSORT_TEST_ATTR(_sdp, _sym) \
    461 	((_sdp->sd_flags & FLG_SY_DYNSORT) || \
    462 	((((_sdp->sd_ref != REF_DYN_NEED) && \
    463 		(_sdp->sd_sym->st_shndx != SHN_UNDEF)) || \
    464 		(_sdp->sd_flags & FLG_SY_MVTOCOMM)) && \
    465 	(_sym->st_size != 0) && \
    466 	!(_sdp->sd_flags & FLG_SY_NODYNSORT)))
    467 
    468 /*
    469  * We use output section descriptor counters to add up the number of
    470  * symbol indexes to put in the .SUNW_dynsort and .SUNW_dyntlssort sections.
    471  * Non-TLS symbols are counted by ofl->ofl_dynsymsortcnt, while TLS symbols are
    472  * counted by ofl->ofl_dyntlssortcnt. This computation is done inline in
    473  * several places. The DYNSORT_COUNT macro allows us to generate this from
    474  * a single description.
    475  *
    476  * entry:
    477  *	_sdp, _sym - As per DYNSORT_TEST_ATTR
    478  *	_type - Type of symbol (STT_*)
    479  *	_inc_or_dec_op - Either ++, or --. This specifies the operation
    480  *		to be applied to the counter, and determines whether we
    481  *		are adding, or removing, a symbol from .SUNW_dynsymsort.
    482  *
    483  * Note that _type is derivable from _sym: ELF_ST_TYPE(_sdp->sd_sym->st_info).
    484  * Most callers already have it in a variable, so this allows us to use that
    485  * variable. If you don't have such a variable, use ELF_ST_TYPE() as shown.
    486  */
    487 #define	DYNSORT_COUNT(_sdp, _sym, _type, _inc_or_dec_op) \
    488 { \
    489 	Word *_cnt_var; \
    490 	\
    491 	if (dynsymsort_symtype[_type]) {	/* Non-TLS counter */ \
    492 		_cnt_var = &ofl->ofl_dynsymsortcnt; \
    493 	} else if ((_type) == STT_TLS) {	/* TLS counter */ \
    494 		_cnt_var = &ofl->ofl_dyntlssortcnt; \
    495 	} else {				/* Don't count this symbol */ \
    496 		_cnt_var = NULL; \
    497 	} \
    498 	if ((_cnt_var != NULL) && DYNSORT_TEST_ATTR(_sdp, _sym)) \
    499 		(*_cnt_var)_inc_or_dec_op;	/* Increment/Decrement */ \
    500 }
    501 
    502 /*
    503  * The OFL_SWAP_RELOC macros are used to determine whether
    504  * relocation processing needs to swap the data being relocated.
    505  * It is an optimization to ld_swap_reloc_data(), as it avoids
    506  * the function call in the case where the linker host and the
    507  * target have the same byte order.
    508  */
    509 #define	OFL_SWAP_RELOC_DATA(_ofl, _rel) \
    510 	(((_ofl)->ofl_flags1 & FLG_OF1_ENCDIFF) && \
    511 	ld_swap_reloc_data(_ofl, _rel))
    512 
    513 /*
    514  * Define an AVL node for maintaining input section descriptors. AVL trees of
    515  * these descriptors are used to process group and COMDAT section.
    516  *
    517  * Pure COMDAT uses the input section name as the search key, while
    518  * SHT_GROUP sections use the name of a special signature symbol. We
    519  * support both by using the isd_name field to carry the name. An alternative
    520  * design would be to use a separate type for each use, saving the cost
    521  * of the unneeded pointer for pure COMDAT. We favor a single implementation
    522  * because we believe that SHT_GROUP comdat will be more common going forward,
    523  * particularly in the largest objects produced by C++ where SHT_GROUP is
    524  * needed to manage the complex section relationships. In contrast, we think
    525  * that pure COMDAT is both more rare, and used in smaller objects where the
    526  * cost of an extra pointer per node is relatively unimportant.
    527  */
    528 typedef struct {
    529 	avl_node_t	isd_avl;	/* avl book-keeping (see SGSOFFSETOF) */
    530 	Is_desc		*isd_isp;	/* input section descriptor */
    531 	const char	*isd_name;	/* name used as search key */
    532 	uint_t		isd_hash;	/* input section name hash value */
    533 } Isd_node;
    534 
    535 /*
    536  * Local data items.
    537  */
    538 extern char		*Plibpath;
    539 extern char		*Llibdir;
    540 extern char		*Ulibdir;
    541 extern Ld_heap		*ld_heap;
    542 extern APlist		*lib_support;
    543 extern int		demangle_flag;
    544 extern const Msg	reject[];
    545 extern int		Verbose;
    546 extern const int	ldynsym_symtype[];
    547 extern const int	dynsymsort_symtype[];
    548 
    549 /*
    550  * Local functions.
    551  */
    552 extern char		*add_string(char *, char *);
    553 extern const char	*demangle(const char *);
    554 
    555 extern void		lds_atexit(Ofl_desc *, int);
    556 
    557 extern void		libld_free(void *);
    558 extern void		*libld_malloc(size_t);
    559 extern void		*libld_realloc(void *, size_t);
    560 
    561 extern int		isdavl_compare(const void *, const void *);
    562 
    563 extern Sdf_desc		*sdf_add(const char *, APlist **);
    564 extern Sdf_desc		*sdf_find(const char *, APlist *);
    565 
    566 #if	defined(_ELF64)
    567 
    568 #define	ld_add_actrel		ld64_add_actrel
    569 #define	ld_add_libdir		ld64_add_libdir
    570 #define	ld_add_rel_cache	ld64_add_rel_cache
    571 #define	ld_adj_movereloc	ld64_adj_movereloc
    572 #define	ld_am_I_partial		ld64_am_I_partial
    573 #define	ld_ar_member		ld64_ar_member
    574 #define	ld_ar_setup		ld64_ar_setup
    575 #define	ld_assign_got_TLS	ld64_assign_got_TLS
    576 #define	ld_bswap_Word		ld64_bswap_Word
    577 #define	ld_bswap_Xword		ld64_bswap_Xword
    578 #define	ld_disp_errmsg		ld64_disp_errmsg
    579 #define	ld_ent_check		ld64_ent_check
    580 #define	ld_exit			ld64_exit
    581 #define	ld_find_library		ld64_find_library
    582 #define	ld_finish_libs		ld64_finish_libs
    583 #define	ld_get_group		ld64_get_group
    584 #define	ld_group_process	ld64_group_process
    585 #define	ld_lib_setup		ld64_lib_setup
    586 #define	ld_init_sighandler	ld64_init_sighandler
    587 #define	ld_lcm			ld64_lcm
    588 #define	ld_make_bss		ld64_make_bss
    589 #define	ld_make_data		ld64_make_data
    590 #define	ld_make_got		ld64_make_got
    591 #define	ld_make_parexpn_data	ld64_make_parexpn_data
    592 #define	ld_make_sunwmove	ld64_make_sunmove
    593 #define	ld_make_text		ld64_make_text
    594 #define	ld_map_out		ld64_map_out
    595 #define	ld_map_parse		ld64_map_parse
    596 #define	ld_open_outfile		ld64_open_outfile
    597 #define	ld_os_first_isdesc	ld64_os_first_isdesc
    598 #define	ld_place_section	ld64_place_section
    599 #define	ld_process_archive	ld64_process_archive
    600 #define	ld_process_files	ld64_process_files
    601 #define	ld_process_flags	ld64_process_flags
    602 #define	ld_process_ifl		ld64_process_ifl
    603 #define	ld_process_move		ld64_process_move
    604 #define	ld_process_open		ld64_process_open
    605 #define	ld_process_ordered	ld64_process_ordered
    606 #define	ld_process_sym_reloc	ld64_process_sym_reloc
    607 #define	ld_reloc_GOT_relative	ld64_reloc_GOT_relative
    608 #define	ld_reloc_plt		ld64_reloc_plt
    609 #define	ld_reloc_remain_entry	ld64_reloc_remain_entry
    610 #define	ld_reloc_targval_get	ld64_reloc_targval_get
    611 #define	ld_reloc_targval_set	ld64_reloc_targval_set
    612 #define	ld_sec_validate		ld64_sec_validate
    613 #define	ld_sort_ordered		ld64_sort_ordered
    614 #define	ld_sort_seg_list	ld64_sort_seg_list
    615 #define	ld_stt_section_sym_name	ld64_stt_section_sym_name
    616 #define	ld_sunw_ldmach		ld64_sunw_ldmach
    617 #define	ld_sup_atexit		ld64_sup_atexit
    618 #define	ld_sup_open		ld64_sup_open
    619 #define	ld_sup_file		ld64_sup_file
    620 #define	ld_sup_loadso		ld64_sup_loadso
    621 #define	ld_sup_input_done	ld64_sup_input_done
    622 #define	ld_sup_input_section	ld64_sup_input_section
    623 #define	ld_sup_section		ld64_sup_section
    624 #define	ld_sup_start		ld64_sup_start
    625 #define	ld_swap_reloc_data	ld64_swap_reloc_data
    626 #define	ld_sym_add_u		ld64_sym_add_u
    627 #define	ld_sym_adjust_vis	ld64_sym_adjust_vis
    628 #define	ld_sym_avl_comp		ld64_sym_avl_comp
    629 #define	ld_sym_copy		ld64_sym_copy
    630 #define	ld_sym_enter		ld64_sym_enter
    631 #define	ld_sym_find		ld64_sym_find
    632 #define	ld_sym_nodirect		ld64_sym_nodirect
    633 #define	ld_sym_process		ld64_sym_process
    634 #define	ld_sym_resolve		ld64_sym_resolve
    635 #define	ld_sym_spec		ld64_sym_spec
    636 #define	ld_targ			ld64_targ
    637 #define	ld_targ_init_sparc	ld64_targ_init_sparc
    638 #define	ld_targ_init_x86	ld64_targ_init_x86
    639 #define	ld_unwind_make_hdr	ld64_unwind_make_hdr
    640 #define	ld_unwind_populate_hdr	ld64_unwind_populate_hdr
    641 #define	ld_unwind_register	ld64_unwind_register
    642 #define	ld_vers_base		ld64_vers_base
    643 #define	ld_vers_check_defs	ld64_vers_check_defs
    644 #define	ld_vers_check_need	ld64_vers_check_need
    645 #define	ld_vers_def_process	ld64_vers_def_process
    646 #define	ld_vers_desc		ld64_vers_desc
    647 #define	ld_vers_find		ld64_vers_find
    648 #define	ld_vers_need_process	ld64_vers_need_process
    649 #define	ld_vers_promote		ld64_vers_promote
    650 #define	ld_vers_sym_process	ld64_vers_sym_process
    651 #define	ld_vers_verify		ld64_vers_verify
    652 #define	ld_wrap_enter		ld64_wrap_enter
    653 
    654 #else
    655 
    656 #define	ld_add_actrel		ld32_add_actrel
    657 #define	ld_add_libdir		ld32_add_libdir
    658 #define	ld_add_rel_cache	ld32_add_rel_cache
    659 #define	ld_adj_movereloc	ld32_adj_movereloc
    660 #define	ld_am_I_partial		ld32_am_I_partial
    661 #define	ld_ar_member		ld32_ar_member
    662 #define	ld_ar_setup		ld32_ar_setup
    663 #define	ld_assign_got_TLS	ld32_assign_got_TLS
    664 #define	ld_bswap_Word		ld32_bswap_Word
    665 #define	ld_bswap_Xword		ld32_bswap_Xword
    666 #define	ld_disp_errmsg		ld32_disp_errmsg
    667 #define	ld_ent_check		ld32_ent_check
    668 #define	ld_exit			ld32_exit
    669 #define	ld_find_library		ld32_find_library
    670 #define	ld_finish_libs		ld32_finish_libs
    671 #define	ld_get_group		ld32_get_group
    672 #define	ld_group_process	ld32_group_process
    673 #define	ld_lib_setup		ld32_lib_setup
    674 #define	ld_init_sighandler	ld32_init_sighandler
    675 #define	ld_lcm			ld32_lcm
    676 #define	ld_make_bss		ld32_make_bss
    677 #define	ld_make_data		ld32_make_data
    678 #define	ld_make_got		ld32_make_got
    679 #define	ld_make_parexpn_data	ld32_make_parexpn_data
    680 #define	ld_make_sunwmove	ld32_make_sunmove
    681 #define	ld_make_text		ld32_make_text
    682 #define	ld_map_out		ld32_map_out
    683 #define	ld_map_parse		ld32_map_parse
    684 #define	ld_open_outfile		ld32_open_outfile
    685 #define	ld_os_first_isdesc	ld32_os_first_isdesc
    686 #define	ld_place_section	ld32_place_section
    687 #define	ld_process_archive	ld32_process_archive
    688 #define	ld_process_files	ld32_process_files
    689 #define	ld_process_flags	ld32_process_flags
    690 #define	ld_process_ifl		ld32_process_ifl
    691 #define	ld_process_move		ld32_process_move
    692 #define	ld_process_open		ld32_process_open
    693 #define	ld_process_ordered	ld32_process_ordered
    694 #define	ld_process_sym_reloc	ld32_process_sym_reloc
    695 #define	ld_reloc_GOT_relative	ld32_reloc_GOT_relative
    696 #define	ld_reloc_plt		ld32_reloc_plt
    697 #define	ld_reloc_remain_entry	ld32_reloc_remain_entry
    698 #define	ld_reloc_targval_get	ld32_reloc_targval_get
    699 #define	ld_reloc_targval_set	ld32_reloc_targval_set
    700 #define	ld_sec_validate		ld32_sec_validate
    701 #define	ld_sort_ordered		ld32_sort_ordered
    702 #define	ld_sort_seg_list	ld32_sort_seg_list
    703 #define	ld_stt_section_sym_name	ld32_stt_section_sym_name
    704 #define	ld_sunw_ldmach		ld32_sunw_ldmach
    705 #define	ld_sup_atexit		ld32_sup_atexit
    706 #define	ld_sup_open		ld32_sup_open
    707 #define	ld_sup_file		ld32_sup_file
    708 #define	ld_sup_loadso		ld32_sup_loadso
    709 #define	ld_sup_input_done	ld32_sup_input_done
    710 #define	ld_sup_input_section	ld32_sup_input_section
    711 #define	ld_sup_section		ld32_sup_section
    712 #define	ld_sup_start		ld32_sup_start
    713 #define	ld_swap_reloc_data	ld32_swap_reloc_data
    714 #define	ld_sym_add_u		ld32_sym_add_u
    715 #define	ld_sym_adjust_vis	ld32_sym_adjust_vis
    716 #define	ld_sym_avl_comp		ld32_sym_avl_comp
    717 #define	ld_sym_copy		ld32_sym_copy
    718 #define	ld_sym_enter		ld32_sym_enter
    719 #define	ld_sym_find		ld32_sym_find
    720 #define	ld_sym_nodirect		ld32_sym_nodirect
    721 #define	ld_sym_process		ld32_sym_process
    722 #define	ld_sym_resolve		ld32_sym_resolve
    723 #define	ld_sym_spec		ld32_sym_spec
    724 #define	ld_targ			ld32_targ
    725 #define	ld_targ_init_sparc	ld32_targ_init_sparc
    726 #define	ld_targ_init_x86	ld32_targ_init_x86
    727 #define	ld_unwind_make_hdr	ld32_unwind_make_hdr
    728 #define	ld_unwind_populate_hdr	ld32_unwind_populate_hdr
    729 #define	ld_unwind_register	ld32_unwind_register
    730 #define	ld_vers_base		ld32_vers_base
    731 #define	ld_vers_check_defs	ld32_vers_check_defs
    732 #define	ld_vers_check_need	ld32_vers_check_need
    733 #define	ld_vers_def_process	ld32_vers_def_process
    734 #define	ld_vers_desc		ld32_vers_desc
    735 #define	ld_vers_find		ld32_vers_find
    736 #define	ld_vers_need_process	ld32_vers_need_process
    737 #define	ld_vers_promote		ld32_vers_promote
    738 #define	ld_vers_sym_process	ld32_vers_sym_process
    739 #define	ld_vers_verify		ld32_vers_verify
    740 #define	ld_wrap_enter		ld32_wrap_enter
    741 
    742 #endif
    743 
    744 extern void		dbg_cleanup(void);
    745 extern int		dbg_setup(Ofl_desc *, const char *, int);
    746 
    747 extern uintptr_t	ld_add_actrel(Word, Rel_desc *, Ofl_desc *);
    748 extern uintptr_t	ld_add_libdir(Ofl_desc *, const char *);
    749 extern Rel_cache	*ld_add_rel_cache(Ofl_desc *, APlist **, size_t *,
    750 			    size_t, size_t);
    751 extern void 		ld_adj_movereloc(Ofl_desc *, Rel_desc *);
    752 extern Sym_desc * 	ld_am_I_partial(Rel_desc *, Xword);
    753 extern void		ld_ar_member(Ar_desc *, Elf_Arsym *, Ar_aux *,
    754 			    Ar_mem *);
    755 extern Ar_desc		*ld_ar_setup(const char *, Elf *, Ofl_desc *);
    756 extern uintptr_t	ld_assign_got_TLS(Boolean, Rel_desc *, Ofl_desc *,
    757 			    Sym_desc *, Gotndx *, Gotref, Word, Word,
    758 			    Word, Word);
    759 
    760 extern Word		ld_bswap_Word(Word);
    761 extern Xword		ld_bswap_Xword(Xword);
    762 
    763 extern void		ld_disp_errmsg(const char *, Rel_desc *, Ofl_desc *);
    764 
    765 extern void		ld_ent_check(Ofl_desc *);
    766 extern int		ld_exit(Ofl_desc *);
    767 
    768 extern uintptr_t	ld_find_library(const char *, Ofl_desc *);
    769 extern uintptr_t	ld_finish_libs(Ofl_desc *);
    770 
    771 extern const char	*ld_stt_section_sym_name(Is_desc *);
    772 
    773 extern Group_desc	*ld_get_group(Ofl_desc *, Is_desc *);
    774 extern uintptr_t	ld_group_process(Is_desc *, Ofl_desc *);
    775 
    776 extern uintptr_t	ld_lib_setup(Ofl_desc *);
    777 
    778 extern void		ld_init_sighandler(Ofl_desc *);
    779 
    780 extern Xword		ld_lcm(Xword, Xword);
    781 
    782 extern uintptr_t	ld_make_bss(Ofl_desc *, Xword, Xword, uint_t);
    783 extern Is_desc		*ld_make_data(Ofl_desc *, size_t);
    784 extern uintptr_t	ld_make_got(Ofl_desc *);
    785 extern uintptr_t	ld_make_parexpn_data(Ofl_desc *, size_t, Xword);
    786 extern uintptr_t	ld_make_sunwmove(Ofl_desc *, int);
    787 extern Is_desc		*ld_make_text(Ofl_desc *, size_t);
    788 extern void		ld_map_out(Ofl_desc *);
    789 extern uintptr_t	ld_map_parse(const char *, Ofl_desc *);
    790 
    791 extern uintptr_t	ld_open_outfile(Ofl_desc *);
    792 
    793 extern Is_desc		*ld_os_first_isdesc(Os_desc *);
    794 extern Os_desc		*ld_place_section(Ofl_desc *, Is_desc *, int,
    795 			    const char *);
    796 extern uintptr_t	ld_process_archive(const char *, int, Ar_desc *,
    797 			    Ofl_desc *);
    798 extern uintptr_t	ld_process_files(Ofl_desc *, int, char **);
    799 extern uintptr_t	ld_process_flags(Ofl_desc *, int, char **);
    800 extern Ifl_desc		*ld_process_ifl(const char *, const char *, int, Elf *,
    801 			    Word, Ofl_desc *, Rej_desc *);
    802 extern uintptr_t	ld_process_move(Ofl_desc *);
    803 extern Ifl_desc		*ld_process_open(const char *, const char *, int *,
    804 			    Ofl_desc *, Word, Rej_desc *);
    805 extern uintptr_t	ld_process_ordered(Ifl_desc *, Ofl_desc *, Word);
    806 extern uintptr_t	ld_process_sym_reloc(Ofl_desc *, Rel_desc *, Rel *,
    807 			    Is_desc *, const char *, Word);
    808 
    809 extern uintptr_t	ld_reloc_GOT_relative(Boolean, Rel_desc *, Ofl_desc *);
    810 extern uintptr_t	ld_reloc_plt(Rel_desc *, Ofl_desc *);
    811 extern void		ld_reloc_remain_entry(Rel_desc *, Os_desc *,
    812 			    Ofl_desc *);
    813 extern int		ld_reloc_targval_get(Ofl_desc *, Rel_desc *,
    814 			    uchar_t *, Xword *);
    815 extern int		ld_reloc_targval_set(Ofl_desc *, Rel_desc *,
    816 			    uchar_t *, Xword);
    817 
    818 extern void		ld_sec_validate(Ofl_desc *);
    819 extern uintptr_t	ld_sort_ordered(Ofl_desc *);
    820 extern uintptr_t	ld_sort_seg_list(Ofl_desc *);
    821 extern Half		ld_sunw_ldmach();
    822 extern void		ld_sup_atexit(Ofl_desc *, int);
    823 extern void		ld_sup_open(Ofl_desc *, const char **, const char **,
    824 			    int *, int, Elf **, Elf *ref, size_t,
    825 			    const Elf_Kind);
    826 extern void		ld_sup_file(Ofl_desc *, const char *, const Elf_Kind,
    827 			    int flags, Elf *);
    828 extern uintptr_t	ld_sup_loadso(Ofl_desc *, const char *);
    829 extern void		ld_sup_input_done(Ofl_desc *);
    830 extern void		ld_sup_section(Ofl_desc *, const char *, Shdr *, Word,
    831 			    Elf_Data *, Elf *);
    832 extern uintptr_t	ld_sup_input_section(Ofl_desc*, Ifl_desc *,
    833 			    const char *, Shdr **, Word, Elf_Scn *, Elf *);
    834 extern void		ld_sup_start(Ofl_desc *, const Half, const char *);
    835 extern int		ld_swap_reloc_data(Ofl_desc *, Rel_desc *);
    836 extern Sym_desc		*ld_sym_add_u(const char *, Ofl_desc *, Msg);
    837 extern void		ld_sym_adjust_vis(Sym_desc *, Ofl_desc *);
    838 extern int		ld_sym_avl_comp(const void *, const void *);
    839 extern uintptr_t	ld_sym_copy(Sym_desc *);
    840 extern Sym_desc		*ld_sym_enter(const char *, Sym *, Word, Ifl_desc *,
    841 			    Ofl_desc *, Word, Word, sd_flag_t, avl_index_t *);
    842 extern Sym_desc		*ld_sym_find(const char *, Word, avl_index_t *,
    843 			    Ofl_desc *);
    844 extern uintptr_t	ld_sym_nodirect(Is_desc *, Ifl_desc *, Ofl_desc *);
    845 extern uintptr_t	ld_sym_process(Is_desc *, Ifl_desc *, Ofl_desc *);
    846 extern uintptr_t	ld_sym_resolve(Sym_desc *, Sym *, Ifl_desc *,
    847 			    Ofl_desc *, int, Word, sd_flag_t);
    848 extern uintptr_t	ld_sym_spec(Ofl_desc *);
    849 
    850 extern Target		ld_targ;
    851 extern const Target	*ld_targ_init_sparc(void);
    852 extern const Target	*ld_targ_init_x86(void);
    853 
    854 extern uintptr_t	ld_unwind_make_hdr(Ofl_desc *);
    855 extern uintptr_t	ld_unwind_populate_hdr(Ofl_desc *);
    856 extern uintptr_t	ld_unwind_register(Os_desc *, Ofl_desc *);
    857 
    858 extern Ver_desc		*ld_vers_base(Ofl_desc *);
    859 extern uintptr_t	ld_vers_check_defs(Ofl_desc *);
    860 extern uintptr_t	ld_vers_check_need(Ofl_desc *);
    861 extern uintptr_t	ld_vers_def_process(Is_desc *, Ifl_desc *, Ofl_desc *);
    862 extern Ver_desc		*ld_vers_desc(const char *, Word, APlist **);
    863 extern Ver_desc		*ld_vers_find(const char *, Word, APlist *);
    864 extern uintptr_t	ld_vers_need_process(Is_desc *, Ifl_desc *, Ofl_desc *);
    865 extern void		ld_vers_promote(Sym_desc *, Word, Ifl_desc *,
    866 			    Ofl_desc *);
    867 extern int		ld_vers_sym_process(Lm_list *, Is_desc *, Ifl_desc *);
    868 extern int		ld_vers_verify(Ofl_desc *);
    869 extern WrapSymNode	*ld_wrap_enter(Ofl_desc *, const char *);
    870 
    871 extern uintptr_t	add_regsym(Sym_desc *, Ofl_desc *);
    872 extern Word		hashbkts(Word);
    873 extern Xword		lcm(Xword, Xword);
    874 
    875 /*
    876  * Most platforms have both a 32 and 64-bit variant (e.g. EM_SPARC and
    877  * EM_SPARCV9). To support this, there many files in libld that are built
    878  * twice, once for ELFCLASS64 (_ELF64), and once for ELFCLASS32. In these
    879  * files, we sometimes want to supply one value for the ELFCLASS32 case
    880  * and another for ELFCLASS64. The LD_TARG_BYCLASS macro is used to do
    881  * this. It is called with both both alternatives, and yields the one
    882  * that applies to the current compilation environment.
    883  */
    884 #ifdef	_ELF64
    885 #define	LD_TARG_BYCLASS(_ec32, _ec64) (_ec64)
    886 #else
    887 #define	LD_TARG_BYCLASS(_ec32, _ec64) (_ec32)
    888 #endif
    889 
    890 
    891 #ifdef	__cplusplus
    892 }
    893 #endif
    894 
    895 #endif /* _LIBLD_DOT_H */
    896