1/* BFD COFF object file private structure.
2   Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
3   2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4   Free Software Foundation, Inc.
5   Written by Cygnus Support.
6
7   This file is part of BFD, the Binary File Descriptor library.
8
9   This program is free software; you can redistribute it and/or modify
10   it under the terms of the GNU General Public License as published by
11   the Free Software Foundation; either version 3 of the License, or
12   (at your option) any later version.
13
14   This program is distributed in the hope that it will be useful,
15   but WITHOUT ANY WARRANTY; without even the implied warranty of
16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17   GNU General Public License for more details.
18
19   You should have received a copy of the GNU General Public License
20   along with this program; if not, write to the Free Software
21   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
22   MA 02110-1301, USA.  */
23
24#include "bfdlink.h"
25
26/* Object file tdata; access macros.  */
27
28#define coff_data(bfd)		      ((bfd)->tdata.coff_obj_data)
29#define obj_pe(bfd)                   (coff_data (bfd)->pe)
30#define obj_symbols(bfd)	      (coff_data (bfd)->symbols)
31#define	obj_sym_filepos(bfd)	      (coff_data (bfd)->sym_filepos)
32#define obj_relocbase(bfd)	      (coff_data (bfd)->relocbase)
33#define obj_raw_syments(bfd)	      (coff_data (bfd)->raw_syments)
34#define obj_raw_syment_count(bfd)     (coff_data (bfd)->raw_syment_count)
35#define obj_convert(bfd)	      (coff_data (bfd)->conversion_table)
36#define obj_conv_table_size(bfd)      (coff_data (bfd)->conv_table_size)
37#define obj_coff_external_syms(bfd)   (coff_data (bfd)->external_syms)
38#define obj_coff_keep_syms(bfd)	      (coff_data (bfd)->keep_syms)
39#define obj_coff_strings(bfd)	      (coff_data (bfd)->strings)
40#define obj_coff_keep_strings(bfd)    (coff_data (bfd)->keep_strings)
41#define obj_coff_sym_hashes(bfd)      (coff_data (bfd)->sym_hashes)
42#define obj_coff_strings_written(bfd) (coff_data (bfd)->strings_written)
43#define obj_coff_local_toc_table(bfd) (coff_data (bfd)->local_toc_sym_map)
44
45/* `Tdata' information kept for COFF files.  */
46
47typedef struct coff_tdata
48{
49  struct coff_symbol_struct *symbols;	/* Symtab for input bfd.  */
50  unsigned int *conversion_table;
51  int conv_table_size;
52  file_ptr sym_filepos;
53
54  struct coff_ptr_struct *raw_syments;
55  unsigned long raw_syment_count;
56
57  /* These are only valid once writing has begun.  */
58  long int relocbase;
59
60  /* These members communicate important constants about the symbol table
61     to GDB's symbol-reading code.  These `constants' unfortunately vary
62     from coff implementation to implementation...  */
63  unsigned local_n_btmask;
64  unsigned local_n_btshft;
65  unsigned local_n_tmask;
66  unsigned local_n_tshift;
67  unsigned local_symesz;
68  unsigned local_auxesz;
69  unsigned local_linesz;
70
71  /* The unswapped external symbols.  May be NULL.  Read by
72     _bfd_coff_get_external_symbols.  */
73  void * external_syms;
74  /* If this is TRUE, the external_syms may not be freed.  */
75  bfd_boolean keep_syms;
76
77  /* The string table.  May be NULL.  Read by
78     _bfd_coff_read_string_table.  */
79  char *strings;
80  /* If this is TRUE, the strings may not be freed.  */
81  bfd_boolean keep_strings;
82  /* If this is TRUE, the strings have been written out already.  */
83  bfd_boolean strings_written;
84
85  /* Is this a PE format coff file?  */
86  int pe;
87  /* Used by the COFF backend linker.  */
88  struct coff_link_hash_entry **sym_hashes;
89
90  /* Used by the pe linker for PowerPC.  */
91  int *local_toc_sym_map;
92
93  struct bfd_link_info *link_info;
94
95  /* Used by coff_find_nearest_line.  */
96  void * line_info;
97
98  /* A place to stash dwarf2 info for this bfd.  */
99  void * dwarf2_find_line_info;
100
101  /* The timestamp from the COFF file header.  */
102  long timestamp;
103
104  /* Copy of some of the f_flags bits in the COFF filehdr structure,
105     used by ARM code.  */
106  flagword flags;
107
108  /* coff-stgo32 EXE stub header after BFD tdata has been allocated.  Its data
109     is kept in internal_filehdr.go32stub beforehand.  */
110  char *go32stub;
111} coff_data_type;
112
113/* Tdata for pe image files.  */
114typedef struct pe_tdata
115{
116  coff_data_type coff;
117  struct internal_extra_pe_aouthdr pe_opthdr;
118  int dll;
119  int has_reloc_section;
120  int dont_strip_reloc;
121  bfd_boolean (*in_reloc_p) (bfd *, reloc_howto_type *);
122  flagword real_flags;
123} pe_data_type;
124
125#define pe_data(bfd)		((bfd)->tdata.pe_obj_data)
126
127/* Tdata for XCOFF files.  */
128
129struct xcoff_tdata
130{
131  /* Basic COFF information.  */
132  coff_data_type coff;
133
134  /* TRUE if this is an XCOFF64 file. */
135  bfd_boolean xcoff64;
136
137  /* TRUE if a large a.out header should be generated.  */
138  bfd_boolean full_aouthdr;
139
140  /* TOC value.  */
141  bfd_vma toc;
142
143  /* Index of section holding TOC.  */
144  int sntoc;
145
146  /* Index of section holding entry point.  */
147  int snentry;
148
149  /* .text alignment from optional header.  */
150  int text_align_power;
151
152  /* .data alignment from optional header.  */
153  int data_align_power;
154
155  /* modtype from optional header.  */
156  short modtype;
157
158  /* cputype from optional header.  */
159  short cputype;
160
161  /* maxdata from optional header.  */
162  bfd_vma maxdata;
163
164  /* maxstack from optional header.  */
165  bfd_vma maxstack;
166
167  /* Used by the XCOFF backend linker.  */
168  asection **csects;
169  long *debug_indices;
170  unsigned int *lineno_counts;
171  unsigned int import_file_id;
172};
173
174#define xcoff_data(abfd) ((abfd)->tdata.xcoff_obj_data)
175
176/* We take the address of the first element of an asymbol to ensure that the
177   macro is only ever applied to an asymbol.  */
178#define coffsymbol(asymbol) ((coff_symbol_type *)(&((asymbol)->the_bfd)))
179
180/* The used_by_bfd field of a section may be set to a pointer to this
181   structure.  */
182
183struct coff_section_tdata
184{
185  /* The relocs, swapped into COFF internal form.  This may be NULL.  */
186  struct internal_reloc *relocs;
187  /* If this is TRUE, the relocs entry may not be freed.  */
188  bfd_boolean keep_relocs;
189  /* The section contents.  This may be NULL.  */
190  bfd_byte *contents;
191  /* If this is TRUE, the contents entry may not be freed.  */
192  bfd_boolean keep_contents;
193  /* Information cached by coff_find_nearest_line.  */
194  bfd_vma offset;
195  unsigned int i;
196  const char *function;
197  /* Optional information about a COMDAT entry; NULL if not COMDAT. */
198  struct coff_comdat_info *comdat;
199  int line_base;
200  /* A pointer used for .stab linking optimizations.  */
201  void * stab_info;
202  /* Available for individual backends.  */
203  void * tdata;
204};
205
206/* An accessor macro for the coff_section_tdata structure.  */
207#define coff_section_data(abfd, sec) \
208  ((struct coff_section_tdata *) (sec)->used_by_bfd)
209
210/* Tdata for sections in XCOFF files.  This is used by the linker.  */
211
212struct xcoff_section_tdata
213{
214  /* Used for XCOFF csects created by the linker; points to the real
215     XCOFF section which contains this csect.  */
216  asection *enclosing;
217  /* The lineno_count field for the enclosing section, because we are
218     going to clobber it there.  */
219  unsigned int lineno_count;
220  /* The first and last symbol indices for symbols used by this csect.  */
221  unsigned long first_symndx;
222  unsigned long last_symndx;
223};
224
225/* An accessor macro the xcoff_section_tdata structure.  */
226#define xcoff_section_data(abfd, sec) \
227  ((struct xcoff_section_tdata *) coff_section_data ((abfd), (sec))->tdata)
228
229/* Tdata for sections in PE files.  */
230
231struct pei_section_tdata
232{
233  /* The virtual size of the section.  */
234  bfd_size_type virt_size;
235  /* The PE section flags.  */
236  long pe_flags;
237};
238
239/* An accessor macro for the pei_section_tdata structure.  */
240#define pei_section_data(abfd, sec) \
241  ((struct pei_section_tdata *) coff_section_data ((abfd), (sec))->tdata)
242
243/* COFF linker hash table entries.  */
244
245struct coff_link_hash_entry
246{
247  struct bfd_link_hash_entry root;
248
249  /* Symbol index in output file.  Set to -1 initially.  Set to -2 if
250     there is a reloc against this symbol.  */
251  long indx;
252
253  /* Symbol type.  */
254  unsigned short type;
255
256  /* Symbol class.  */
257  unsigned char symbol_class;
258
259  /* Number of auxiliary entries.  */
260  char numaux;
261
262  /* BFD to take auxiliary entries from.  */
263  bfd *auxbfd;
264
265  /* Pointer to array of auxiliary entries, if any.  */
266  union internal_auxent *aux;
267
268  /* Flag word; legal values follow.  */
269  unsigned short coff_link_hash_flags;
270  /* Symbol is a PE section symbol.  */
271#define COFF_LINK_HASH_PE_SECTION_SYMBOL (01)
272};
273
274/* COFF linker hash table.  */
275
276struct coff_link_hash_table
277{
278  struct bfd_link_hash_table root;
279  /* A pointer to information used to link stabs in sections.  */
280  struct stab_info stab_info;
281};
282
283/* Look up an entry in a COFF linker hash table.  */
284
285#define coff_link_hash_lookup(table, string, create, copy, follow)	\
286  ((struct coff_link_hash_entry *)					\
287   bfd_link_hash_lookup (&(table)->root, (string), (create),		\
288			 (copy), (follow)))
289
290/* Traverse a COFF linker hash table.  */
291
292#define coff_link_hash_traverse(table, func, info)			\
293  (bfd_link_hash_traverse						\
294   (&(table)->root,							\
295    (bfd_boolean (*) (struct bfd_link_hash_entry *, void *)) (func), \
296    (info)))
297
298/* Get the COFF linker hash table from a link_info structure.  */
299
300#define coff_hash_table(p) ((struct coff_link_hash_table *) ((p)->hash))
301
302/* Functions in coffgen.c.  */
303extern const bfd_target *coff_object_p
304  (bfd *);
305extern struct bfd_section *coff_section_from_bfd_index
306  (bfd *, int);
307extern long coff_get_symtab_upper_bound
308  (bfd *);
309extern long coff_canonicalize_symtab
310  (bfd *, asymbol **);
311extern int coff_count_linenumbers
312  (bfd *);
313extern struct coff_symbol_struct *coff_symbol_from
314  (bfd *, asymbol *);
315extern bfd_boolean coff_renumber_symbols
316  (bfd *, int *);
317extern void coff_mangle_symbols
318  (bfd *);
319extern bfd_boolean coff_write_symbols
320  (bfd *);
321extern bfd_boolean coff_write_linenumbers
322  (bfd *);
323extern alent *coff_get_lineno
324  (bfd *, asymbol *);
325extern asymbol *coff_section_symbol
326  (bfd *, char *);
327extern bfd_boolean _bfd_coff_get_external_symbols
328  (bfd *);
329extern const char *_bfd_coff_read_string_table
330  (bfd *);
331extern bfd_boolean _bfd_coff_free_symbols
332  (bfd *);
333extern struct coff_ptr_struct *coff_get_normalized_symtab
334  (bfd *);
335extern long coff_get_reloc_upper_bound
336  (bfd *, sec_ptr);
337extern asymbol *coff_make_empty_symbol
338  (bfd *);
339extern void coff_print_symbol
340  (bfd *, void * filep, asymbol *, bfd_print_symbol_type);
341extern void coff_get_symbol_info
342  (bfd *, asymbol *, symbol_info *ret);
343extern bfd_boolean _bfd_coff_is_local_label_name
344  (bfd *, const char *);
345extern asymbol *coff_bfd_make_debug_symbol
346  (bfd *, void *, unsigned long);
347extern bfd_boolean coff_find_nearest_line
348  (bfd *, asection *, asymbol **, bfd_vma, const char **,
349   const char **, unsigned int *);
350extern bfd_boolean coff_find_inliner_info
351  (bfd *, const char **, const char **, unsigned int *);
352extern int coff_sizeof_headers
353  (bfd *, struct bfd_link_info *);
354extern bfd_boolean bfd_coff_reloc16_relax_section
355  (bfd *, asection *, struct bfd_link_info *, bfd_boolean *);
356extern bfd_byte *bfd_coff_reloc16_get_relocated_section_contents
357  (bfd *, struct bfd_link_info *, struct bfd_link_order *,
358   bfd_byte *, bfd_boolean, asymbol **);
359extern bfd_vma bfd_coff_reloc16_get_value
360  (arelent *, struct bfd_link_info *, asection *);
361extern void bfd_perform_slip
362  (bfd *, unsigned int, asection *, bfd_vma);
363
364/* Functions and types in cofflink.c.  */
365
366#define STRING_SIZE_SIZE 4
367
368/* We use a hash table to merge identical enum, struct, and union
369   definitions in the linker.  */
370
371/* Information we keep for a single element (an enum value, a
372   structure or union field) in the debug merge hash table.  */
373
374struct coff_debug_merge_element
375{
376  /* Next element.  */
377  struct coff_debug_merge_element *next;
378
379  /* Name.  */
380  const char *name;
381
382  /* Type.  */
383  unsigned int type;
384
385  /* Symbol index for complex type.  */
386  long tagndx;
387};
388
389/* A linked list of debug merge entries for a given name.  */
390
391struct coff_debug_merge_type
392{
393  /* Next type with the same name.  */
394  struct coff_debug_merge_type *next;
395
396  /* Class of type.  */
397  int type_class;
398
399  /* Symbol index where this type is defined.  */
400  long indx;
401
402  /* List of elements.  */
403  struct coff_debug_merge_element *elements;
404};
405
406/* Information we store in the debug merge hash table.  */
407
408struct coff_debug_merge_hash_entry
409{
410  struct bfd_hash_entry root;
411
412  /* A list of types with this name.  */
413  struct coff_debug_merge_type *types;
414};
415
416/* The debug merge hash table.  */
417
418struct coff_debug_merge_hash_table
419{
420  struct bfd_hash_table root;
421};
422
423/* Initialize a COFF debug merge hash table.  */
424
425#define coff_debug_merge_hash_table_init(table) \
426  (bfd_hash_table_init (&(table)->root, _bfd_coff_debug_merge_hash_newfunc, \
427			sizeof (struct coff_debug_merge_hash_entry)))
428
429/* Free a COFF debug merge hash table.  */
430
431#define coff_debug_merge_hash_table_free(table) \
432  (bfd_hash_table_free (&(table)->root))
433
434/* Look up an entry in a COFF debug merge hash table.  */
435
436#define coff_debug_merge_hash_lookup(table, string, create, copy) \
437  ((struct coff_debug_merge_hash_entry *) \
438   bfd_hash_lookup (&(table)->root, (string), (create), (copy)))
439
440/* Information we keep for each section in the output file when doing
441   a relocatable link.  */
442
443struct coff_link_section_info
444{
445  /* The relocs to be output.  */
446  struct internal_reloc *relocs;
447  /* For each reloc against a global symbol whose index was not known
448     when the reloc was handled, the global hash table entry.  */
449  struct coff_link_hash_entry **rel_hashes;
450};
451
452/* Information that we pass around while doing the final link step.  */
453
454struct coff_final_link_info
455{
456  /* General link information.  */
457  struct bfd_link_info *info;
458  /* Output BFD.  */
459  bfd *output_bfd;
460  /* Used to indicate failure in traversal routine.  */
461  bfd_boolean failed;
462  /* If doing "task linking" set only during the time when we want the
463     global symbol writer to convert the storage class of defined global
464     symbols from global to static. */
465  bfd_boolean global_to_static;
466  /* Hash table for long symbol names.  */
467  struct bfd_strtab_hash *strtab;
468  /* When doing a relocatable link, an array of information kept for
469     each output section, indexed by the target_index field.  */
470  struct coff_link_section_info *section_info;
471  /* Symbol index of last C_FILE symbol (-1 if none).  */
472  long last_file_index;
473  /* Contents of last C_FILE symbol.  */
474  struct internal_syment last_file;
475  /* Symbol index of first aux entry of last .bf symbol with an empty
476     endndx field (-1 if none).  */
477  long last_bf_index;
478  /* Contents of last_bf_index aux entry.  */
479  union internal_auxent last_bf;
480  /* Hash table used to merge debug information.  */
481  struct coff_debug_merge_hash_table debug_merge;
482  /* Buffer large enough to hold swapped symbols of any input file.  */
483  struct internal_syment *internal_syms;
484  /* Buffer large enough to hold sections of symbols of any input file.  */
485  asection **sec_ptrs;
486  /* Buffer large enough to hold output indices of symbols of any
487     input file.  */
488  long *sym_indices;
489  /* Buffer large enough to hold output symbols for any input file.  */
490  bfd_byte *outsyms;
491  /* Buffer large enough to hold external line numbers for any input
492     section.  */
493  bfd_byte *linenos;
494  /* Buffer large enough to hold any input section.  */
495  bfd_byte *contents;
496  /* Buffer large enough to hold external relocs of any input section.  */
497  bfd_byte *external_relocs;
498  /* Buffer large enough to hold swapped relocs of any input section.  */
499  struct internal_reloc *internal_relocs;
500};
501
502/* Most COFF variants have no way to record the alignment of a
503   section.  This struct is used to set a specific alignment based on
504   the name of the section.  */
505
506struct coff_section_alignment_entry
507{
508  /* The section name.  */
509  const char *name;
510
511  /* This is either (unsigned int) -1, indicating that the section
512     name must match exactly, or it is the number of letters which
513     must match at the start of the name.  */
514  unsigned int comparison_length;
515
516  /* These macros may be used to fill in the first two fields in a
517     structure initialization.  */
518#define COFF_SECTION_NAME_EXACT_MATCH(name) (name), ((unsigned int) -1)
519#define COFF_SECTION_NAME_PARTIAL_MATCH(name) (name), (sizeof (name) - 1)
520
521  /* Only use this entry if the default section alignment for this
522     target is at least that much (as a power of two).  If this field
523     is COFF_ALIGNMENT_FIELD_EMPTY, it should be ignored.  */
524  unsigned int default_alignment_min;
525
526  /* Only use this entry if the default section alignment for this
527     target is no greater than this (as a power of two).  If this
528     field is COFF_ALIGNMENT_FIELD_EMPTY, it should be ignored.  */
529  unsigned int default_alignment_max;
530
531#define COFF_ALIGNMENT_FIELD_EMPTY ((unsigned int) -1)
532
533  /* The desired alignment for this section (as a power of two).  */
534  unsigned int alignment_power;
535};
536
537extern struct bfd_hash_entry *_bfd_coff_link_hash_newfunc
538  (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
539extern bfd_boolean _bfd_coff_link_hash_table_init
540  (struct coff_link_hash_table *, bfd *,
541   struct bfd_hash_entry *(*) (struct bfd_hash_entry *,
542			       struct bfd_hash_table *,
543			       const char *),
544   unsigned int);
545extern struct bfd_link_hash_table *_bfd_coff_link_hash_table_create
546  (bfd *);
547extern const char *_bfd_coff_internal_syment_name
548  (bfd *, const struct internal_syment *, char *);
549extern bfd_boolean _bfd_coff_link_add_symbols
550  (bfd *, struct bfd_link_info *);
551extern bfd_boolean _bfd_coff_final_link
552  (bfd *, struct bfd_link_info *);
553extern struct internal_reloc *_bfd_coff_read_internal_relocs
554  (bfd *, asection *, bfd_boolean, bfd_byte *, bfd_boolean,
555   struct internal_reloc *);
556extern bfd_boolean _bfd_coff_generic_relocate_section
557  (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
558   struct internal_reloc *, struct internal_syment *, asection **);
559extern struct bfd_hash_entry *_bfd_coff_debug_merge_hash_newfunc
560  (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
561extern bfd_boolean _bfd_coff_write_global_sym
562  (struct coff_link_hash_entry *, void *);
563extern bfd_boolean _bfd_coff_write_task_globals
564  (struct coff_link_hash_entry *, void *);
565extern bfd_boolean _bfd_coff_link_input_bfd
566  (struct coff_final_link_info *, bfd *);
567extern bfd_boolean _bfd_coff_reloc_link_order
568  (bfd *, struct coff_final_link_info *, asection *,
569   struct bfd_link_order *);
570
571
572#define coff_get_section_contents_in_window \
573  _bfd_generic_get_section_contents_in_window
574
575/* Functions in xcofflink.c.  */
576
577extern long _bfd_xcoff_get_dynamic_symtab_upper_bound
578  (bfd *);
579extern long _bfd_xcoff_canonicalize_dynamic_symtab
580  (bfd *, asymbol **);
581extern long _bfd_xcoff_get_dynamic_reloc_upper_bound
582  (bfd *);
583extern long _bfd_xcoff_canonicalize_dynamic_reloc
584  (bfd *, arelent **, asymbol **);
585extern struct bfd_link_hash_table *_bfd_xcoff_bfd_link_hash_table_create
586  (bfd *);
587extern void _bfd_xcoff_bfd_link_hash_table_free
588  (struct bfd_link_hash_table *);
589extern bfd_boolean _bfd_xcoff_bfd_link_add_symbols
590  (bfd *, struct bfd_link_info *);
591extern bfd_boolean _bfd_xcoff_bfd_final_link
592  (bfd *, struct bfd_link_info *);
593extern bfd_boolean _bfd_xcoff_define_common_symbol
594  (bfd *, struct bfd_link_info *, struct bfd_link_hash_entry *);
595extern bfd_boolean _bfd_ppc_xcoff_relocate_section
596  (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
597   struct internal_reloc *, struct internal_syment *, asection **);
598
599/* Functions in coff-ppc.c.  FIXME: These are called by pe.em in the
600   linker, and so should start with bfd and be declared in bfd.h.  */
601
602extern bfd_boolean ppc_allocate_toc_section
603  (struct bfd_link_info *);
604extern bfd_boolean ppc_process_before_allocation
605  (bfd *, struct bfd_link_info *);
606