move minimal symbols to per-bfd
[binutils-gdb.git] / gdb / objfiles.h
1 /* Definitions for symbol file management in GDB.
2
3 Copyright (C) 1992-2014 Free Software Foundation, Inc.
4
5 This file is part of GDB.
6
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 3 of the License, or
10 (at your option) any later version.
11
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.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19
20 #if !defined (OBJFILES_H)
21 #define OBJFILES_H
22
23 #include "gdb_obstack.h" /* For obstack internals. */
24 #include "symfile.h" /* For struct psymbol_allocation_list. */
25 #include "progspace.h"
26 #include "registry.h"
27 #include "gdb_bfd.h"
28
29 struct bcache;
30 struct htab;
31 struct symtab;
32 struct objfile_data;
33
34 /* This structure maintains information on a per-objfile basis about the
35 "entry point" of the objfile, and the scope within which the entry point
36 exists. It is possible that gdb will see more than one objfile that is
37 executable, each with its own entry point.
38
39 For example, for dynamically linked executables in SVR4, the dynamic linker
40 code is contained within the shared C library, which is actually executable
41 and is run by the kernel first when an exec is done of a user executable
42 that is dynamically linked. The dynamic linker within the shared C library
43 then maps in the various program segments in the user executable and jumps
44 to the user executable's recorded entry point, as if the call had been made
45 directly by the kernel.
46
47 The traditional gdb method of using this info was to use the
48 recorded entry point to set the entry-file's lowpc and highpc from
49 the debugging information, where these values are the starting
50 address (inclusive) and ending address (exclusive) of the
51 instruction space in the executable which correspond to the
52 "startup file", i.e. crt0.o in most cases. This file is assumed to
53 be a startup file and frames with pc's inside it are treated as
54 nonexistent. Setting these variables is necessary so that
55 backtraces do not fly off the bottom of the stack.
56
57 NOTE: cagney/2003-09-09: It turns out that this "traditional"
58 method doesn't work. Corinna writes: ``It turns out that the call
59 to test for "inside entry file" destroys a meaningful backtrace
60 under some conditions. E.g. the backtrace tests in the asm-source
61 testcase are broken for some targets. In this test the functions
62 are all implemented as part of one file and the testcase is not
63 necessarily linked with a start file (depending on the target).
64 What happens is, that the first frame is printed normaly and
65 following frames are treated as being inside the enttry file then.
66 This way, only the #0 frame is printed in the backtrace output.''
67 Ref "frame.c" "NOTE: vinschen/2003-04-01".
68
69 Gdb also supports an alternate method to avoid running off the bottom
70 of the stack.
71
72 There are two frames that are "special", the frame for the function
73 containing the process entry point, since it has no predecessor frame,
74 and the frame for the function containing the user code entry point
75 (the main() function), since all the predecessor frames are for the
76 process startup code. Since we have no guarantee that the linked
77 in startup modules have any debugging information that gdb can use,
78 we need to avoid following frame pointers back into frames that might
79 have been built in the startup code, as we might get hopelessly
80 confused. However, we almost always have debugging information
81 available for main().
82
83 These variables are used to save the range of PC values which are
84 valid within the main() function and within the function containing
85 the process entry point. If we always consider the frame for
86 main() as the outermost frame when debugging user code, and the
87 frame for the process entry point function as the outermost frame
88 when debugging startup code, then all we have to do is have
89 DEPRECATED_FRAME_CHAIN_VALID return false whenever a frame's
90 current PC is within the range specified by these variables. In
91 essence, we set "ceilings" in the frame chain beyond which we will
92 not proceed when following the frame chain back up the stack.
93
94 A nice side effect is that we can still debug startup code without
95 running off the end of the frame chain, assuming that we have usable
96 debugging information in the startup modules, and if we choose to not
97 use the block at main, or can't find it for some reason, everything
98 still works as before. And if we have no startup code debugging
99 information but we do have usable information for main(), backtraces
100 from user code don't go wandering off into the startup code. */
101
102 struct entry_info
103 {
104 /* The unrelocated value we should use for this objfile entry point. */
105 CORE_ADDR entry_point;
106
107 /* The index of the section in which the entry point appears. */
108 int the_bfd_section_index;
109
110 /* Set to 1 iff ENTRY_POINT contains a valid value. */
111 unsigned entry_point_p : 1;
112
113 /* Set to 1 iff this object was initialized. */
114 unsigned initialized : 1;
115 };
116
117 /* Sections in an objfile. The section offsets are stored in the
118 OBJFILE. */
119
120 struct obj_section
121 {
122 struct bfd_section *the_bfd_section; /* BFD section pointer */
123
124 /* Objfile this section is part of. */
125 struct objfile *objfile;
126
127 /* True if this "overlay section" is mapped into an "overlay region". */
128 int ovly_mapped;
129 };
130
131 /* Relocation offset applied to S. */
132 #define obj_section_offset(s) \
133 (((s)->objfile->section_offsets)->offsets[gdb_bfd_section_index ((s)->objfile->obfd, (s)->the_bfd_section)])
134
135 /* The memory address of section S (vma + offset). */
136 #define obj_section_addr(s) \
137 (bfd_get_section_vma ((s)->objfile->obfd, s->the_bfd_section) \
138 + obj_section_offset (s))
139
140 /* The one-passed-the-end memory address of section S
141 (vma + size + offset). */
142 #define obj_section_endaddr(s) \
143 (bfd_get_section_vma ((s)->objfile->obfd, s->the_bfd_section) \
144 + bfd_get_section_size ((s)->the_bfd_section) \
145 + obj_section_offset (s))
146
147 /* The "objstats" structure provides a place for gdb to record some
148 interesting information about its internal state at runtime, on a
149 per objfile basis, such as information about the number of symbols
150 read, size of string table (if any), etc. */
151
152 struct objstats
153 {
154 int n_minsyms; /* Number of minimal symbols read */
155 int n_psyms; /* Number of partial symbols read */
156 int n_syms; /* Number of full symbols read */
157 int n_stabs; /* Number of ".stabs" read (if applicable) */
158 int n_types; /* Number of types */
159 int sz_strtab; /* Size of stringtable, (if applicable) */
160 };
161
162 #define OBJSTAT(objfile, expr) (objfile -> stats.expr)
163 #define OBJSTATS struct objstats stats
164 extern void print_objfile_statistics (void);
165 extern void print_symbol_bcache_statistics (void);
166
167 /* Number of entries in the minimal symbol hash table. */
168 #define MINIMAL_SYMBOL_HASH_SIZE 2039
169
170 /* Some objfile data is hung off the BFD. This enables sharing of the
171 data across all objfiles using the BFD. The data is stored in an
172 instance of this structure, and associated with the BFD using the
173 registry system. */
174
175 struct objfile_per_bfd_storage
176 {
177 /* The storage has an obstack of its own. */
178
179 struct obstack storage_obstack;
180
181 /* Byte cache for file names. */
182
183 struct bcache *filename_cache;
184
185 /* Byte cache for macros. */
186 struct bcache *macro_cache;
187
188 /* The gdbarch associated with the BFD. Note that this gdbarch is
189 determined solely from BFD information, without looking at target
190 information. The gdbarch determined from a running target may
191 differ from this e.g. with respect to register types and names. */
192
193 struct gdbarch *gdbarch;
194
195 /* Hash table for mapping symbol names to demangled names. Each
196 entry in the hash table is actually two consecutive strings,
197 both null-terminated; the first one is a mangled or linkage
198 name, and the second is the demangled name or just a zero byte
199 if the name doesn't demangle. */
200 struct htab *demangled_names_hash;
201
202 /* The per-objfile information about the entry point, the scope (file/func)
203 containing the entry point, and the scope of the user's main() func. */
204
205 struct entry_info ei;
206
207 /* The name and language of any "main" found in this objfile. The
208 name can be NULL, which means that the information was not
209 recorded. */
210
211 const char *name_of_main;
212 enum language language_of_main;
213
214 /* Each file contains a pointer to an array of minimal symbols for all
215 global symbols that are defined within the file. The array is
216 terminated by a "null symbol", one that has a NULL pointer for the
217 name and a zero value for the address. This makes it easy to walk
218 through the array when passed a pointer to somewhere in the middle
219 of it. There is also a count of the number of symbols, which does
220 not include the terminating null symbol. The array itself, as well
221 as all the data that it points to, should be allocated on the
222 objfile_obstack for this file. */
223
224 struct minimal_symbol *msymbols;
225 int minimal_symbol_count;
226
227 /* This is true if minimal symbols have already been read. Symbol
228 readers can use this to bypass minimal symbol reading. Also, the
229 minimal symbol table management code in minsyms.c uses this to
230 suppress new minimal symbols. You might think that MSYMBOLS or
231 MINIMAL_SYMBOL_COUNT could be used for this, but it is possible
232 for multiple readers to install minimal symbols into a given
233 per-BFD. */
234
235 unsigned int minsyms_read : 1;
236
237 /* This is a hash table used to index the minimal symbols by name. */
238
239 struct minimal_symbol *msymbol_hash[MINIMAL_SYMBOL_HASH_SIZE];
240
241 /* This hash table is used to index the minimal symbols by their
242 demangled names. */
243
244 struct minimal_symbol *msymbol_demangled_hash[MINIMAL_SYMBOL_HASH_SIZE];
245 };
246
247 /* Master structure for keeping track of each file from which
248 gdb reads symbols. There are several ways these get allocated: 1.
249 The main symbol file, symfile_objfile, set by the symbol-file command,
250 2. Additional symbol files added by the add-symbol-file command,
251 3. Shared library objfiles, added by ADD_SOLIB, 4. symbol files
252 for modules that were loaded when GDB attached to a remote system
253 (see remote-vx.c). */
254
255 struct objfile
256 {
257
258 /* All struct objfile's are chained together by their next pointers.
259 The program space field "objfiles" (frequently referenced via
260 the macro "object_files") points to the first link in this
261 chain. */
262
263 struct objfile *next;
264
265 /* The object file's original name as specified by the user,
266 made absolute, and tilde-expanded. However, it is not canonicalized
267 (i.e., it has not been passed through gdb_realpath).
268 This pointer is never NULL. This does not have to be freed; it is
269 guaranteed to have a lifetime at least as long as the objfile. */
270
271 char *original_name;
272
273 CORE_ADDR addr_low;
274
275 /* Some flag bits for this objfile.
276 The values are defined by OBJF_*. */
277
278 unsigned short flags;
279
280 /* The program space associated with this objfile. */
281
282 struct program_space *pspace;
283
284 /* Each objfile points to a linked list of symtabs derived from this file,
285 one symtab structure for each compilation unit (source file). Each link
286 in the symtab list contains a backpointer to this objfile. */
287
288 struct symtab *symtabs;
289
290 /* Each objfile points to a linked list of partial symtabs derived from
291 this file, one partial symtab structure for each compilation unit
292 (source file). */
293
294 struct partial_symtab *psymtabs;
295
296 /* Map addresses to the entries of PSYMTABS. It would be more efficient to
297 have a map per the whole process but ADDRMAP cannot selectively remove
298 its items during FREE_OBJFILE. This mapping is already present even for
299 PARTIAL_SYMTABs which still have no corresponding full SYMTABs read. */
300
301 struct addrmap *psymtabs_addrmap;
302
303 /* List of freed partial symtabs, available for re-use. */
304
305 struct partial_symtab *free_psymtabs;
306
307 /* The object file's BFD. Can be null if the objfile contains only
308 minimal symbols, e.g. the run time common symbols for SunOS4. */
309
310 bfd *obfd;
311
312 /* The per-BFD data. Note that this is treated specially if OBFD
313 is NULL. */
314
315 struct objfile_per_bfd_storage *per_bfd;
316
317 /* The modification timestamp of the object file, as of the last time
318 we read its symbols. */
319
320 long mtime;
321
322 /* Obstack to hold objects that should be freed when we load a new symbol
323 table from this object file. */
324
325 struct obstack objfile_obstack;
326
327 /* A byte cache where we can stash arbitrary "chunks" of bytes that
328 will not change. */
329
330 struct psymbol_bcache *psymbol_cache; /* Byte cache for partial syms. */
331
332 /* Vectors of all partial symbols read in from file. The actual data
333 is stored in the objfile_obstack. */
334
335 struct psymbol_allocation_list global_psymbols;
336 struct psymbol_allocation_list static_psymbols;
337
338 /* Structure which keeps track of functions that manipulate objfile's
339 of the same type as this objfile. I.e. the function to read partial
340 symbols for example. Note that this structure is in statically
341 allocated memory, and is shared by all objfiles that use the
342 object module reader of this type. */
343
344 const struct sym_fns *sf;
345
346 /* Per objfile data-pointers required by other GDB modules. */
347
348 REGISTRY_FIELDS;
349
350 /* Set of relocation offsets to apply to each section.
351 The table is indexed by the_bfd_section->index, thus it is generally
352 as large as the number of sections in the binary.
353 The table is stored on the objfile_obstack.
354
355 These offsets indicate that all symbols (including partial and
356 minimal symbols) which have been read have been relocated by this
357 much. Symbols which are yet to be read need to be relocated by it. */
358
359 struct section_offsets *section_offsets;
360 int num_sections;
361
362 /* Indexes in the section_offsets array. These are initialized by the
363 *_symfile_offsets() family of functions (som_symfile_offsets,
364 xcoff_symfile_offsets, default_symfile_offsets). In theory they
365 should correspond to the section indexes used by bfd for the
366 current objfile. The exception to this for the time being is the
367 SOM version. */
368
369 int sect_index_text;
370 int sect_index_data;
371 int sect_index_bss;
372 int sect_index_rodata;
373
374 /* These pointers are used to locate the section table, which
375 among other things, is used to map pc addresses into sections.
376 SECTIONS points to the first entry in the table, and
377 SECTIONS_END points to the first location past the last entry
378 in the table. The table is stored on the objfile_obstack. The
379 sections are indexed by the BFD section index; but the
380 structure data is only valid for certain sections
381 (e.g. non-empty, SEC_ALLOC). */
382
383 struct obj_section *sections, *sections_end;
384
385 /* GDB allows to have debug symbols in separate object files. This is
386 used by .gnu_debuglink, ELF build id note and Mach-O OSO.
387 Although this is a tree structure, GDB only support one level
388 (ie a separate debug for a separate debug is not supported). Note that
389 separate debug object are in the main chain and therefore will be
390 visited by ALL_OBJFILES & co iterators. Separate debug objfile always
391 has a non-nul separate_debug_objfile_backlink. */
392
393 /* Link to the first separate debug object, if any. */
394 struct objfile *separate_debug_objfile;
395
396 /* If this is a separate debug object, this is used as a link to the
397 actual executable objfile. */
398 struct objfile *separate_debug_objfile_backlink;
399
400 /* If this is a separate debug object, this is a link to the next one
401 for the same executable objfile. */
402 struct objfile *separate_debug_objfile_link;
403
404 /* Place to stash various statistics about this objfile. */
405 OBJSTATS;
406
407 /* A linked list of symbols created when reading template types or
408 function templates. These symbols are not stored in any symbol
409 table, so we have to keep them here to relocate them
410 properly. */
411 struct symbol *template_symbols;
412 };
413
414 /* Defines for the objfile flag word. */
415
416 /* When an object file has its functions reordered (currently Irix-5.2
417 shared libraries exhibit this behaviour), we will need an expensive
418 algorithm to locate a partial symtab or symtab via an address.
419 To avoid this penalty for normal object files, we use this flag,
420 whose setting is determined upon symbol table read in. */
421
422 #define OBJF_REORDERED (1 << 0) /* Functions are reordered */
423
424 /* Distinguish between an objfile for a shared library and a "vanilla"
425 objfile. (If not set, the objfile may still actually be a solib.
426 This can happen if the user created the objfile by using the
427 add-symbol-file command. GDB doesn't in that situation actually
428 check whether the file is a solib. Rather, the target's
429 implementation of the solib interface is responsible for setting
430 this flag when noticing solibs used by an inferior.) */
431
432 #define OBJF_SHARED (1 << 1) /* From a shared library */
433
434 /* User requested that this objfile be read in it's entirety. */
435
436 #define OBJF_READNOW (1 << 2) /* Immediate full read */
437
438 /* This objfile was created because the user explicitly caused it
439 (e.g., used the add-symbol-file command). This bit offers a way
440 for run_command to remove old objfile entries which are no longer
441 valid (i.e., are associated with an old inferior), but to preserve
442 ones that the user explicitly loaded via the add-symbol-file
443 command. */
444
445 #define OBJF_USERLOADED (1 << 3) /* User loaded */
446
447 /* Set if we have tried to read partial symtabs for this objfile.
448 This is used to allow lazy reading of partial symtabs. */
449
450 #define OBJF_PSYMTABS_READ (1 << 4)
451
452 /* Set if this is the main symbol file
453 (as opposed to symbol file for dynamically loaded code). */
454
455 #define OBJF_MAINLINE (1 << 5)
456
457 /* ORIGINAL_NAME and OBFD->FILENAME correspond to text description unrelated to
458 filesystem names. It can be for example "<image in memory>". */
459
460 #define OBJF_NOT_FILENAME (1 << 6)
461
462 /* Declarations for functions defined in objfiles.c */
463
464 extern struct objfile *allocate_objfile (bfd *, const char *name, int);
465
466 extern struct gdbarch *get_objfile_arch (struct objfile *);
467
468 extern int entry_point_address_query (CORE_ADDR *entry_p);
469
470 extern CORE_ADDR entry_point_address (void);
471
472 extern void build_objfile_section_table (struct objfile *);
473
474 extern void terminate_minimal_symbol_table (struct objfile *objfile);
475
476 extern struct objfile *objfile_separate_debug_iterate (const struct objfile *,
477 const struct objfile *);
478
479 extern void put_objfile_before (struct objfile *, struct objfile *);
480
481 extern void add_separate_debug_objfile (struct objfile *, struct objfile *);
482
483 extern void unlink_objfile (struct objfile *);
484
485 extern void free_objfile (struct objfile *);
486
487 extern void free_objfile_separate_debug (struct objfile *);
488
489 extern struct cleanup *make_cleanup_free_objfile (struct objfile *);
490
491 extern void free_all_objfiles (void);
492
493 extern void objfile_relocate (struct objfile *, const struct section_offsets *);
494 extern void objfile_rebase (struct objfile *, CORE_ADDR);
495
496 extern int objfile_has_partial_symbols (struct objfile *objfile);
497
498 extern int objfile_has_full_symbols (struct objfile *objfile);
499
500 extern int objfile_has_symbols (struct objfile *objfile);
501
502 extern int have_partial_symbols (void);
503
504 extern int have_full_symbols (void);
505
506 extern void objfile_set_sym_fns (struct objfile *objfile,
507 const struct sym_fns *sf);
508
509 extern void objfiles_changed (void);
510
511 extern int is_addr_in_objfile (CORE_ADDR addr, const struct objfile *objfile);
512
513 /* This operation deletes all objfile entries that represent solibs that
514 weren't explicitly loaded by the user, via e.g., the add-symbol-file
515 command. */
516
517 extern void objfile_purge_solibs (void);
518
519 /* Functions for dealing with the minimal symbol table, really a misc
520 address<->symbol mapping for things we don't have debug symbols for. */
521
522 extern int have_minimal_symbols (void);
523
524 extern struct obj_section *find_pc_section (CORE_ADDR pc);
525
526 /* Return non-zero if PC is in a section called NAME. */
527 extern int pc_in_section (CORE_ADDR, char *);
528
529 /* Return non-zero if PC is in a SVR4-style procedure linkage table
530 section. */
531
532 static inline int
533 in_plt_section (CORE_ADDR pc)
534 {
535 return pc_in_section (pc, ".plt");
536 }
537
538 /* Keep a registry of per-objfile data-pointers required by other GDB
539 modules. */
540 DECLARE_REGISTRY(objfile);
541
542 /* In normal use, the section map will be rebuilt by find_pc_section
543 if objfiles have been added, removed or relocated since it was last
544 called. Calling inhibit_section_map_updates will inhibit this
545 behavior until resume_section_map_updates is called. If you call
546 inhibit_section_map_updates you must ensure that every call to
547 find_pc_section in the inhibited region relates to a section that
548 is already in the section map and has not since been removed or
549 relocated. */
550 extern void inhibit_section_map_updates (struct program_space *pspace);
551
552 /* Resume automatically rebuilding the section map as required. */
553 extern void resume_section_map_updates (struct program_space *pspace);
554
555 /* Version of the above suitable for use as a cleanup. */
556 extern void resume_section_map_updates_cleanup (void *arg);
557
558 extern void default_iterate_over_objfiles_in_search_order
559 (struct gdbarch *gdbarch,
560 iterate_over_objfiles_in_search_order_cb_ftype *cb,
561 void *cb_data, struct objfile *current_objfile);
562 \f
563
564 /* Traverse all object files in the current program space.
565 ALL_OBJFILES_SAFE works even if you delete the objfile during the
566 traversal. */
567
568 /* Traverse all object files in program space SS. */
569
570 #define ALL_PSPACE_OBJFILES(ss, obj) \
571 for ((obj) = ss->objfiles; (obj) != NULL; (obj) = (obj)->next)
572
573 #define ALL_PSPACE_OBJFILES_SAFE(ss, obj, nxt) \
574 for ((obj) = ss->objfiles; \
575 (obj) != NULL? ((nxt)=(obj)->next,1) :0; \
576 (obj) = (nxt))
577
578 #define ALL_OBJFILES(obj) \
579 for ((obj) = current_program_space->objfiles; \
580 (obj) != NULL; \
581 (obj) = (obj)->next)
582
583 #define ALL_OBJFILES_SAFE(obj,nxt) \
584 for ((obj) = current_program_space->objfiles; \
585 (obj) != NULL? ((nxt)=(obj)->next,1) :0; \
586 (obj) = (nxt))
587
588 /* Traverse all symtabs in one objfile. */
589
590 #define ALL_OBJFILE_SYMTABS(objfile, s) \
591 for ((s) = (objfile) -> symtabs; (s) != NULL; (s) = (s) -> next)
592
593 /* Traverse all primary symtabs in one objfile. */
594
595 #define ALL_OBJFILE_PRIMARY_SYMTABS(objfile, s) \
596 ALL_OBJFILE_SYMTABS ((objfile), (s)) \
597 if ((s)->primary)
598
599 /* Traverse all minimal symbols in one objfile. */
600
601 #define ALL_OBJFILE_MSYMBOLS(objfile, m) \
602 for ((m) = (objfile)->per_bfd->msymbols; \
603 MSYMBOL_LINKAGE_NAME (m) != NULL; \
604 (m)++)
605
606 /* Traverse all symtabs in all objfiles in the current symbol
607 space. */
608
609 #define ALL_SYMTABS(objfile, s) \
610 ALL_OBJFILES (objfile) \
611 ALL_OBJFILE_SYMTABS (objfile, s)
612
613 #define ALL_PSPACE_SYMTABS(ss, objfile, s) \
614 ALL_PSPACE_OBJFILES (ss, objfile) \
615 ALL_OBJFILE_SYMTABS (objfile, s)
616
617 /* Traverse all symtabs in all objfiles in the current program space,
618 skipping included files (which share a blockvector with their
619 primary symtab). */
620
621 #define ALL_PRIMARY_SYMTABS(objfile, s) \
622 ALL_OBJFILES (objfile) \
623 ALL_OBJFILE_PRIMARY_SYMTABS (objfile, s)
624
625 #define ALL_PSPACE_PRIMARY_SYMTABS(pspace, objfile, s) \
626 ALL_PSPACE_OBJFILES (ss, objfile) \
627 ALL_OBJFILE_PRIMARY_SYMTABS (objfile, s)
628
629 /* Traverse all minimal symbols in all objfiles in the current symbol
630 space. */
631
632 #define ALL_MSYMBOLS(objfile, m) \
633 ALL_OBJFILES (objfile) \
634 ALL_OBJFILE_MSYMBOLS (objfile, m)
635
636 #define ALL_OBJFILE_OSECTIONS(objfile, osect) \
637 for (osect = objfile->sections; osect < objfile->sections_end; osect++) \
638 if (osect->the_bfd_section == NULL) \
639 { \
640 /* Nothing. */ \
641 } \
642 else
643
644 /* Traverse all obj_sections in all objfiles in the current program
645 space.
646
647 Note that this detects a "break" in the inner loop, and exits
648 immediately from the outer loop as well, thus, client code doesn't
649 need to know that this is implemented with a double for. The extra
650 hair is to make sure that a "break;" stops the outer loop iterating
651 as well, and both OBJFILE and OSECT are left unmodified:
652
653 - The outer loop learns about the inner loop's end condition, and
654 stops iterating if it detects the inner loop didn't reach its
655 end. In other words, the outer loop keeps going only if the
656 inner loop reached its end cleanly [(osect) ==
657 (objfile)->sections_end].
658
659 - OSECT is initialized in the outer loop initialization
660 expressions, such as if the inner loop has reached its end, so
661 the check mentioned above succeeds the first time.
662
663 - The trick to not clearing OBJFILE on a "break;" is, in the outer
664 loop's loop expression, advance OBJFILE, but iff the inner loop
665 reached its end. If not, there was a "break;", so leave OBJFILE
666 as is; the outer loop's conditional will break immediately as
667 well (as OSECT will be different from OBJFILE->sections_end). */
668
669 #define ALL_OBJSECTIONS(objfile, osect) \
670 for ((objfile) = current_program_space->objfiles, \
671 (objfile) != NULL ? ((osect) = (objfile)->sections_end) : 0; \
672 (objfile) != NULL \
673 && (osect) == (objfile)->sections_end; \
674 ((osect) == (objfile)->sections_end \
675 ? ((objfile) = (objfile)->next, \
676 (objfile) != NULL ? (osect) = (objfile)->sections_end : 0) \
677 : 0)) \
678 ALL_OBJFILE_OSECTIONS (objfile, osect)
679
680 #define SECT_OFF_DATA(objfile) \
681 ((objfile->sect_index_data == -1) \
682 ? (internal_error (__FILE__, __LINE__, \
683 _("sect_index_data not initialized")), -1) \
684 : objfile->sect_index_data)
685
686 #define SECT_OFF_RODATA(objfile) \
687 ((objfile->sect_index_rodata == -1) \
688 ? (internal_error (__FILE__, __LINE__, \
689 _("sect_index_rodata not initialized")), -1) \
690 : objfile->sect_index_rodata)
691
692 #define SECT_OFF_TEXT(objfile) \
693 ((objfile->sect_index_text == -1) \
694 ? (internal_error (__FILE__, __LINE__, \
695 _("sect_index_text not initialized")), -1) \
696 : objfile->sect_index_text)
697
698 /* Sometimes the .bss section is missing from the objfile, so we don't
699 want to die here. Let the users of SECT_OFF_BSS deal with an
700 uninitialized section index. */
701 #define SECT_OFF_BSS(objfile) (objfile)->sect_index_bss
702
703 /* Answer whether there is more than one object file loaded. */
704
705 #define MULTI_OBJFILE_P() (object_files && object_files->next)
706
707 /* Reset the per-BFD storage area on OBJ. */
708
709 void set_objfile_per_bfd (struct objfile *obj);
710
711 const char *objfile_name (const struct objfile *objfile);
712
713 /* Set the objfile's notion of the "main" name and language. */
714
715 extern void set_objfile_main_name (struct objfile *objfile,
716 const char *name, enum language lang);
717
718 #endif /* !defined (OBJFILES_H) */