1 /* BFD back-end data structures for a.out (and similar) files.
2 Copyright 1990, 91, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
3 Written by Cygnus Support.
5 This file is part of BFD, the Binary File Descriptor library.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
24 /* We try to encapsulate the differences in the various a.out file
25 variants in a few routines, and otherwise share large masses of code.
26 This means we only have to fix bugs in one place, most of the time. */
30 /* Parameterize the a.out code based on whether it is being built
31 for a 32-bit architecture or a 64-bit architecture. */
33 #define GET_WORD bfd_h_get_64
34 #define GET_SWORD bfd_h_get_signed_64
35 #define PUT_WORD bfd_h_put_64
37 #define NAME(x,y) CAT3(x,_64_,y)
39 #define JNAME(x) CAT(x,_64)
40 #define BYTES_IN_WORD 8
41 #else /* ARCH_SIZE == 32 */
42 #define GET_WORD bfd_h_get_32
43 #define GET_SWORD bfd_h_get_signed_32
44 #define PUT_WORD bfd_h_put_32
46 #define NAME(x,y) CAT3(x,_32_,y)
48 #define JNAME(x) CAT(x,_32)
49 #define BYTES_IN_WORD 4
50 #endif /* ARCH_SIZE==32 */
52 /* Declare at file level, since used in parameter lists, which have
55 struct external_nlist;
56 struct reloc_ext_external;
57 struct reloc_std_external;
59 /* a.out backend linker hash table entries. */
61 struct aout_link_hash_entry
63 struct bfd_link_hash_entry root;
64 /* Whether this symbol has been written out. */
66 /* Symbol index in output file. */
70 /* a.out backend linker hash table. */
72 struct aout_link_hash_table
74 struct bfd_link_hash_table root;
77 /* Look up an entry in an a.out link hash table. */
79 #define aout_link_hash_lookup(table, string, create, copy, follow) \
80 ((struct aout_link_hash_entry *) \
81 bfd_link_hash_lookup (&(table)->root, (string), (create), (copy), (follow)))
83 /* Traverse an a.out link hash table. */
85 #define aout_link_hash_traverse(table, func, info) \
86 (bfd_link_hash_traverse \
88 (boolean (*) PARAMS ((struct bfd_link_hash_entry *, PTR))) (func), \
91 /* Get the a.out link hash table from the info structure. This is
94 #define aout_hash_table(p) ((struct aout_link_hash_table *) ((p)->hash))
96 /* Back-end information for various a.out targets. */
97 struct aout_backend_data
99 /* Are ZMAGIC files mapped contiguously? If so, the text section may
100 need more padding, if the segment size (granularity for memory access
101 control) is larger than the page size. */
102 unsigned char zmagic_mapped_contiguous;
103 /* If this flag is set, ZMAGIC/NMAGIC file headers get mapped in with the
104 text section, which starts immediately after the file header.
105 If not, the text section starts on the next page. */
106 unsigned char text_includes_header;
108 /* The value to pass to N_SET_FLAGS. */
109 unsigned char exec_hdr_flags;
111 /* If the text section VMA isn't specified, and we need an absolute
112 address, use this as the default. If we're producing a relocatable
113 file, zero is always used. */
114 /* ?? Perhaps a callback would be a better choice? Will this do anything
115 reasonable for a format that handles multiple CPUs with different
116 load addresses for each? */
117 bfd_vma default_text_vma;
119 /* Callback for setting the page and segment sizes, if they can't be
120 trivially determined from the architecture. */
121 boolean (*set_sizes) PARAMS ((bfd *));
123 /* zmagic files only. For go32, the length of the exec header contributes
124 to the size of the text section in the file for alignment purposes but
125 does *not* get counted in the length of the text section. */
126 unsigned char exec_header_not_counted;
128 /* Callback from the add symbols phase of the linker code to handle
130 boolean (*add_dynamic_symbols) PARAMS ((bfd *, struct bfd_link_info *,
131 struct external_nlist **,
132 bfd_size_type *, char **));
134 /* Callback from the add symbols phase of the linker code to handle
135 adding a single symbol to the global linker hash table. */
136 boolean (*add_one_symbol) PARAMS ((struct bfd_link_info *, bfd *,
137 const char *, flagword, asection *,
138 bfd_vma, const char *, boolean,
140 struct bfd_link_hash_entry **));
142 /* Called to handle linking a dynamic object. */
143 boolean (*link_dynamic_object) PARAMS ((struct bfd_link_info *, bfd *));
145 /* Called for each global symbol being written out by the linker.
146 This should write out the dynamic symbol information. */
147 boolean (*write_dynamic_symbol) PARAMS ((bfd *, struct bfd_link_info *,
148 struct aout_link_hash_entry *));
150 /* If this callback is not NULL, the linker calls it for each reloc.
151 RELOC is a pointer to the unswapped reloc. If *SKIP is set to
152 true, the reloc will be skipped. *RELOCATION may be changed to
153 change the effects of the relocation. */
154 boolean (*check_dynamic_reloc) PARAMS ((struct bfd_link_info *info,
156 asection *input_section,
157 struct aout_link_hash_entry *h,
158 PTR reloc, bfd_byte *contents,
160 bfd_vma *relocation));
162 /* Called at the end of a link to finish up any dynamic linking
164 boolean (*finish_dynamic_link) PARAMS ((bfd *, struct bfd_link_info *));
166 #define aout_backend_info(abfd) \
167 ((CONST struct aout_backend_data *)((abfd)->xvec->backend_data))
169 /* This is the layout in memory of a "struct exec" while we process it.
170 All 'lengths' are given as a number of bytes.
171 All 'alignments' are for relinkable files only; an alignment of
172 'n' indicates the corresponding segment must begin at an
173 address that is a multiple of (2**n). */
177 long a_info; /* Magic number and flags, packed */
178 bfd_vma a_text; /* length of text, in bytes */
179 bfd_vma a_data; /* length of data, in bytes */
180 bfd_vma a_bss; /* length of uninitialized data area in mem */
181 bfd_vma a_syms; /* length of symbol table data in file */
182 bfd_vma a_entry; /* start address */
183 bfd_vma a_trsize; /* length of text's relocation info, in bytes */
184 bfd_vma a_drsize; /* length of data's relocation info, in bytes */
186 bfd_vma a_tload; /* Text runtime load address */
187 bfd_vma a_dload; /* Data runtime load address */
188 unsigned char a_talign; /* Alignment of text segment */
189 unsigned char a_dalign; /* Alignment of data segment */
190 unsigned char a_balign; /* Alignment of bss segment */
191 char a_relaxable; /* Enough info for linker relax */
194 /* Magic number is written
196 3130292827262524232221201918171615141312111009080706050403020100
197 < FLAGS >< MACHINE TYPE >< MAGIC NUMBER >
199 /* Magic number for NetBSD is
201 3130292827262524232221201918171615141312111009080706050403020100
202 < FLAGS >< >< MAGIC NUMBER >
210 /* skip a bunch so we don't run into any of suns numbers */
211 /* make these up for the ns32k*/
212 M_NS32032 = (64), /* ns32032 running ? */
213 M_NS32532 = (64 + 5), /* ns32532 running mach */
216 M_29K = 101, /* AMD 29000 */
217 M_386_DYNIX = 102, /* Sequent running dynix */
218 M_ARM = 103, /* Advanced Risc Machines ARM */
219 M_386_NETBSD = 134, /* NetBSD/i386 binary */
220 M_68K_NETBSD = 135, /* NetBSD/m68k binary */
221 M_68K4K_NETBSD = 136, /* NetBSD/m68k4k binary */
222 M_532_NETBSD = 137, /* NetBSD/ns32k binary */
223 M_SPARC_NETBSD = 138, /* NetBSD/sparc binary */
224 M_MIPS1 = 151, /* MIPS R2000/R3000 binary */
225 M_MIPS2 = 152, /* MIPS R4000/R6000 binary */
226 /* start-sanitize-rce */
227 M_RCE = 155, /* Motorola RCE binary */
228 /* end-sanitize-rce */
229 M_HP200 = 200, /* HP 200 (68010) BSD binary */
230 M_HP300 = (300 % 256), /* HP 300 (68020+68881) BSD binary */
231 M_HPUX = (0x20c % 256)/* HP 200/300 HPUX binary */
234 #define N_DYNAMIC(exec) ((exec).a_info & 0x80000000)
237 # define N_MAGIC(exec) ((exec).a_info & 0xffff)
241 # define N_MACHTYPE(exec) ((enum machine_type)(((exec).a_info >> 16) & 0xff))
245 # define N_FLAGS(exec) (((exec).a_info >> 24) & 0xff)
249 # define N_SET_INFO(exec, magic, type, flags) \
250 ((exec).a_info = ((magic) & 0xffff) \
251 | (((int)(type) & 0xff) << 16) \
252 | (((flags) & 0xff) << 24))
255 #ifndef N_SET_DYNAMIC
256 # define N_SET_DYNAMIC(exec, dynamic) \
257 ((exec).a_info = (dynamic) ? ((exec).a_info | 0x80000000) : \
258 ((exec).a_info & 0x7fffffff))
262 # define N_SET_MAGIC(exec, magic) \
263 ((exec).a_info = (((exec).a_info & 0xffff0000) | ((magic) & 0xffff)))
266 #ifndef N_SET_MACHTYPE
267 # define N_SET_MACHTYPE(exec, machtype) \
269 ((exec).a_info&0xff00ffff) | ((((int)(machtype))&0xff) << 16))
273 # define N_SET_FLAGS(exec, flags) \
275 ((exec).a_info&0x00ffffff) | (((flags) & 0xff) << 24))
278 typedef struct aout_symbol {
285 /* The `tdata' struct for all a.out-like object file formats.
286 Various things depend on this struct being around any time an a.out
287 file is being handled. An example is dbxread.c in GDB. */
290 struct internal_exec *hdr; /* exec file header */
291 aout_symbol_type *symbols; /* symtab for input bfd */
293 /* For ease, we do this */
298 /* We remember these offsets so that after check_file_format, we have
299 no dependencies on the particular format of the exec_hdr. */
300 file_ptr sym_filepos;
301 file_ptr str_filepos;
303 /* Size of a relocation entry in external form */
304 unsigned reloc_entry_size;
306 /* Size of a symbol table entry in external form */
307 unsigned symbol_entry_size;
309 /* Page size - needed for alignment of demand paged files. */
310 unsigned long page_size;
312 /* Segment size - needed for alignment of demand paged files. */
313 unsigned long segment_size;
315 /* Zmagic disk block size - need to align the start of the text
316 section in ZMAGIC binaries. Normally the same as page_size. */
317 unsigned long zmagic_disk_block_size;
319 unsigned exec_bytes_size;
320 unsigned vma_adjusted : 1;
322 /* used when a bfd supports several highly similar formats */
326 /* Used on HP 9000/300 running HP/UX. See hp300hpux.c. */
328 /* Used on Linux, 386BSD, etc. See include/aout/aout64.h. */
340 /* A buffer for find_nearest_line. */
343 /* The external symbol information. */
344 struct external_nlist *external_syms;
345 bfd_size_type external_sym_count;
346 bfd_window sym_window;
347 char *external_strings;
348 bfd_size_type external_string_size;
349 bfd_window string_window;
350 struct aout_link_hash_entry **sym_hashes;
352 /* A pointer for shared library information. */
355 /* A mapping from local symbols to offsets into the global offset
356 table, used when linking on SunOS. This is indexed by the symbol
358 bfd_vma *local_got_offsets;
361 struct aout_data_struct {
363 struct internal_exec e;
366 #define adata(bfd) ((bfd)->tdata.aout_data->a)
367 #define exec_hdr(bfd) (adata(bfd).hdr)
368 #define obj_aout_symbols(bfd) (adata(bfd).symbols)
369 #define obj_textsec(bfd) (adata(bfd).textsec)
370 #define obj_datasec(bfd) (adata(bfd).datasec)
371 #define obj_bsssec(bfd) (adata(bfd).bsssec)
372 #define obj_sym_filepos(bfd) (adata(bfd).sym_filepos)
373 #define obj_str_filepos(bfd) (adata(bfd).str_filepos)
374 #define obj_reloc_entry_size(bfd) (adata(bfd).reloc_entry_size)
375 #define obj_symbol_entry_size(bfd) (adata(bfd).symbol_entry_size)
376 #define obj_aout_subformat(bfd) (adata(bfd).subformat)
377 #define obj_aout_external_syms(bfd) (adata(bfd).external_syms)
378 #define obj_aout_external_sym_count(bfd) (adata(bfd).external_sym_count)
379 #define obj_aout_sym_window(bfd) (adata(bfd).sym_window)
380 #define obj_aout_external_strings(bfd) (adata(bfd).external_strings)
381 #define obj_aout_external_string_size(bfd) (adata(bfd).external_string_size)
382 #define obj_aout_string_window(bfd) (adata(bfd).string_window)
383 #define obj_aout_sym_hashes(bfd) (adata(bfd).sym_hashes)
384 #define obj_aout_dynamic_info(bfd) (adata(bfd).dynamic_info)
386 /* We take the address of the first element of an asymbol to ensure that the
387 macro is only ever applied to an asymbol */
388 #define aout_symbol(asymbol) ((aout_symbol_type *)(&(asymbol)->the_bfd))
390 /* Information we keep for each a.out section. This is currently only
391 used by the a.out backend linker. */
393 struct aout_section_data_struct
395 /* The unswapped relocation entries for this section. */
399 #define aout_section_data(s) \
400 ((struct aout_section_data_struct *) (s)->used_by_bfd)
402 #define set_aout_section_data(s,v) \
403 ((s)->used_by_bfd = (PTR)&(v)->relocs)
405 /* Prototype declarations for functions defined in aoutx.h */
408 NAME(aout,squirt_out_relocs) PARAMS ((bfd *abfd, asection *section));
411 NAME(aout,make_sections) PARAMS ((bfd *));
414 NAME(aout,some_aout_object_p) PARAMS ((bfd *abfd,
415 struct internal_exec *execp,
416 const bfd_target *(*callback)(bfd *)));
419 NAME(aout,mkobject) PARAMS ((bfd *abfd));
422 NAME(aout,machine_type) PARAMS ((enum bfd_architecture arch,
423 unsigned long machine,
427 NAME(aout,set_arch_mach) PARAMS ((bfd *abfd, enum bfd_architecture arch,
428 unsigned long machine));
431 NAME(aout,new_section_hook) PARAMS ((bfd *abfd, asection *newsect));
434 NAME(aout,set_section_contents) PARAMS ((bfd *abfd, sec_ptr section,
435 PTR location, file_ptr offset, bfd_size_type count));
438 NAME(aout,make_empty_symbol) PARAMS ((bfd *abfd));
441 NAME(aout,translate_symbol_table) PARAMS ((bfd *, aout_symbol_type *,
442 struct external_nlist *,
443 bfd_size_type, char *,
448 NAME(aout,slurp_symbol_table) PARAMS ((bfd *abfd));
451 NAME(aout,write_syms) PARAMS ((bfd *abfd));
454 NAME(aout,reclaim_symbol_table) PARAMS ((bfd *abfd));
457 NAME(aout,get_symtab_upper_bound) PARAMS ((bfd *abfd));
460 NAME(aout,get_symtab) PARAMS ((bfd *abfd, asymbol **location));
463 NAME(aout,swap_ext_reloc_in) PARAMS ((bfd *, struct reloc_ext_external *,
464 arelent *, asymbol **, bfd_size_type));
466 NAME(aout,swap_std_reloc_in) PARAMS ((bfd *, struct reloc_std_external *,
467 arelent *, asymbol **, bfd_size_type));
470 NAME(aout,reloc_type_lookup) PARAMS ((bfd *abfd,
471 bfd_reloc_code_real_type code));
474 NAME(aout,slurp_reloc_table) PARAMS ((bfd *abfd, sec_ptr asect,
478 NAME(aout,canonicalize_reloc) PARAMS ((bfd *abfd, sec_ptr section,
479 arelent **relptr, asymbol **symbols));
482 NAME(aout,get_reloc_upper_bound) PARAMS ((bfd *abfd, sec_ptr asect));
485 NAME(aout,reclaim_reloc) PARAMS ((bfd *ignore_abfd, sec_ptr ignore));
488 NAME(aout,get_lineno) PARAMS ((bfd *ignore_abfd, asymbol *ignore_symbol));
491 NAME(aout,print_symbol) PARAMS ((bfd *ignore_abfd, PTR file,
492 asymbol *symbol, bfd_print_symbol_type how));
495 NAME(aout,get_symbol_info) PARAMS ((bfd *ignore_abfd,
496 asymbol *symbol, symbol_info *ret));
499 NAME(aout,find_nearest_line) PARAMS ((bfd *abfd, asection *section,
500 asymbol **symbols, bfd_vma offset, CONST char **filename_ptr,
501 CONST char **functionname_ptr, unsigned int *line_ptr));
504 NAME(aout,read_minisymbols) PARAMS ((bfd *, boolean, PTR *, unsigned int *));
507 NAME(aout,minisymbol_to_symbol) PARAMS ((bfd *, boolean, const PTR,
511 NAME(aout,sizeof_headers) PARAMS ((bfd *abfd, boolean exec));
514 NAME(aout,adjust_sizes_and_vmas) PARAMS ((bfd *abfd,
515 bfd_size_type *text_size, file_ptr *text_end));
518 NAME(aout,swap_exec_header_in) PARAMS ((bfd *abfd,
519 struct external_exec *raw_bytes, struct internal_exec *execp));
522 NAME(aout,swap_exec_header_out) PARAMS ((bfd *abfd,
523 struct internal_exec *execp, struct external_exec *raw_bytes));
525 struct bfd_hash_entry *
526 NAME(aout,link_hash_newfunc)
527 PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *));
530 NAME(aout,link_hash_table_init)
531 PARAMS ((struct aout_link_hash_table *, bfd *,
532 struct bfd_hash_entry *(*) (struct bfd_hash_entry *,
533 struct bfd_hash_table *,
536 struct bfd_link_hash_table *
537 NAME(aout,link_hash_table_create) PARAMS ((bfd *));
540 NAME(aout,link_add_symbols) PARAMS ((bfd *, struct bfd_link_info *));
543 NAME(aout,final_link) PARAMS ((bfd *, struct bfd_link_info *,
544 void (*) (bfd *, file_ptr *, file_ptr *,
548 NAME(aout,bfd_free_cached_info) PARAMS ((bfd *));
550 /* A.out uses the generic versions of these routines... */
552 #define aout_32_get_section_contents _bfd_generic_get_section_contents
554 #define aout_64_get_section_contents _bfd_generic_get_section_contents
555 #ifndef NO_WRITE_HEADER_KLUDGE
556 #define NO_WRITE_HEADER_KLUDGE 0
559 #ifndef aout_32_bfd_is_local_label
560 #define aout_32_bfd_is_local_label bfd_generic_is_local_label
563 #ifndef WRITE_HEADERS
564 #define WRITE_HEADERS(abfd, execp) \
566 bfd_size_type text_size; /* dummy vars */ \
568 if (adata(abfd).magic == undecided_magic) \
569 NAME(aout,adjust_sizes_and_vmas) (abfd, &text_size, &text_end); \
571 execp->a_syms = bfd_get_symcount (abfd) * EXTERNAL_NLIST_SIZE; \
572 execp->a_entry = bfd_get_start_address (abfd); \
574 execp->a_trsize = ((obj_textsec (abfd)->reloc_count) * \
575 obj_reloc_entry_size (abfd)); \
576 execp->a_drsize = ((obj_datasec (abfd)->reloc_count) * \
577 obj_reloc_entry_size (abfd)); \
578 NAME(aout,swap_exec_header_out) (abfd, execp, &exec_bytes); \
580 if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0) return false; \
581 if (bfd_write ((PTR) &exec_bytes, 1, EXEC_BYTES_SIZE, abfd) \
582 != EXEC_BYTES_SIZE) \
584 /* Now write out reloc info, followed by syms and strings */ \
586 if (bfd_get_outsymbols (abfd) != (asymbol **) NULL \
587 && bfd_get_symcount (abfd) != 0) \
589 if (bfd_seek (abfd, (file_ptr)(N_SYMOFF(*execp)), SEEK_SET) \
593 if (! NAME(aout,write_syms)(abfd)) return false; \
595 if (bfd_seek (abfd, (file_ptr)(N_TRELOFF(*execp)), SEEK_SET) \
599 if (!NAME(aout,squirt_out_relocs) (abfd, obj_textsec (abfd))) \
601 if (bfd_seek (abfd, (file_ptr)(N_DRELOFF(*execp)), SEEK_SET) \
605 if (!NAME(aout,squirt_out_relocs)(abfd, obj_datasec (abfd))) \
611 #endif /* ! defined (LIBAOUT_H) */