xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/objfiles.h (revision ccd9df534e375a4366c5b55f23782053c7a98d82)
1 /* Definitions for symbol file management in GDB.
2 
3    Copyright (C) 1992-2020 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 "hashtab.h"
24 #include "gdb_obstack.h"	/* For obstack internals.  */
25 #include "objfile-flags.h"
26 #include "symfile.h"
27 #include "progspace.h"
28 #include "registry.h"
29 #include "gdb_bfd.h"
30 #include "psymtab.h"
31 #include <atomic>
32 #include <bitset>
33 #include <vector>
34 #include "gdbsupport/next-iterator.h"
35 #include "gdbsupport/safe-iterator.h"
36 #include "bcache.h"
37 #include "gdbarch.h"
38 #include "gdbsupport/refcounted-object.h"
39 #include "jit.h"
40 
41 struct htab;
42 struct objfile_data;
43 struct partial_symbol;
44 
45 /* This structure maintains information on a per-objfile basis about the
46    "entry point" of the objfile, and the scope within which the entry point
47    exists.  It is possible that gdb will see more than one objfile that is
48    executable, each with its own entry point.
49 
50    For example, for dynamically linked executables in SVR4, the dynamic linker
51    code is contained within the shared C library, which is actually executable
52    and is run by the kernel first when an exec is done of a user executable
53    that is dynamically linked.  The dynamic linker within the shared C library
54    then maps in the various program segments in the user executable and jumps
55    to the user executable's recorded entry point, as if the call had been made
56    directly by the kernel.
57 
58    The traditional gdb method of using this info was to use the
59    recorded entry point to set the entry-file's lowpc and highpc from
60    the debugging information, where these values are the starting
61    address (inclusive) and ending address (exclusive) of the
62    instruction space in the executable which correspond to the
63    "startup file", i.e. crt0.o in most cases.  This file is assumed to
64    be a startup file and frames with pc's inside it are treated as
65    nonexistent.  Setting these variables is necessary so that
66    backtraces do not fly off the bottom of the stack.
67 
68    NOTE: cagney/2003-09-09: It turns out that this "traditional"
69    method doesn't work.  Corinna writes: ``It turns out that the call
70    to test for "inside entry file" destroys a meaningful backtrace
71    under some conditions.  E.g. the backtrace tests in the asm-source
72    testcase are broken for some targets.  In this test the functions
73    are all implemented as part of one file and the testcase is not
74    necessarily linked with a start file (depending on the target).
75    What happens is, that the first frame is printed normally and
76    following frames are treated as being inside the entry file then.
77    This way, only the #0 frame is printed in the backtrace output.''
78    Ref "frame.c" "NOTE: vinschen/2003-04-01".
79 
80    Gdb also supports an alternate method to avoid running off the bottom
81    of the stack.
82 
83    There are two frames that are "special", the frame for the function
84    containing the process entry point, since it has no predecessor frame,
85    and the frame for the function containing the user code entry point
86    (the main() function), since all the predecessor frames are for the
87    process startup code.  Since we have no guarantee that the linked
88    in startup modules have any debugging information that gdb can use,
89    we need to avoid following frame pointers back into frames that might
90    have been built in the startup code, as we might get hopelessly
91    confused.  However, we almost always have debugging information
92    available for main().
93 
94    These variables are used to save the range of PC values which are
95    valid within the main() function and within the function containing
96    the process entry point.  If we always consider the frame for
97    main() as the outermost frame when debugging user code, and the
98    frame for the process entry point function as the outermost frame
99    when debugging startup code, then all we have to do is have
100    DEPRECATED_FRAME_CHAIN_VALID return false whenever a frame's
101    current PC is within the range specified by these variables.  In
102    essence, we set "ceilings" in the frame chain beyond which we will
103    not proceed when following the frame chain back up the stack.
104 
105    A nice side effect is that we can still debug startup code without
106    running off the end of the frame chain, assuming that we have usable
107    debugging information in the startup modules, and if we choose to not
108    use the block at main, or can't find it for some reason, everything
109    still works as before.  And if we have no startup code debugging
110    information but we do have usable information for main(), backtraces
111    from user code don't go wandering off into the startup code.  */
112 
113 struct entry_info
114 {
115   /* The unrelocated value we should use for this objfile entry point.  */
116   CORE_ADDR entry_point;
117 
118   /* The index of the section in which the entry point appears.  */
119   int the_bfd_section_index;
120 
121   /* Set to 1 iff ENTRY_POINT contains a valid value.  */
122   unsigned entry_point_p : 1;
123 
124   /* Set to 1 iff this object was initialized.  */
125   unsigned initialized : 1;
126 };
127 
128 /* Sections in an objfile.  The section offsets are stored in the
129    OBJFILE.  */
130 
131 struct obj_section
132 {
133   /* BFD section pointer */
134   struct bfd_section *the_bfd_section;
135 
136   /* Objfile this section is part of.  */
137   struct objfile *objfile;
138 
139   /* True if this "overlay section" is mapped into an "overlay region".  */
140   int ovly_mapped;
141 };
142 
143 /* Relocation offset applied to S.  */
144 #define obj_section_offset(s)						\
145   (((s)->objfile->section_offsets)[gdb_bfd_section_index ((s)->objfile->obfd, (s)->the_bfd_section)])
146 
147 /* The memory address of section S (vma + offset).  */
148 #define obj_section_addr(s)				      		\
149   (bfd_section_vma (s->the_bfd_section)					\
150    + obj_section_offset (s))
151 
152 /* The one-passed-the-end memory address of section S
153    (vma + size + offset).  */
154 #define obj_section_endaddr(s)						\
155   (bfd_section_vma (s->the_bfd_section)					\
156    + bfd_section_size ((s)->the_bfd_section)				\
157    + obj_section_offset (s))
158 
159 #define ALL_OBJFILE_OSECTIONS(objfile, osect)	\
160   for (osect = objfile->sections; osect < objfile->sections_end; osect++) \
161     if (osect->the_bfd_section == NULL)					\
162       {									\
163 	/* Nothing.  */							\
164       }									\
165     else
166 
167 #define SECT_OFF_DATA(objfile) \
168      ((objfile->sect_index_data == -1) \
169       ? (internal_error (__FILE__, __LINE__, \
170 			 _("sect_index_data not initialized")), -1)	\
171       : objfile->sect_index_data)
172 
173 #define SECT_OFF_RODATA(objfile) \
174      ((objfile->sect_index_rodata == -1) \
175       ? (internal_error (__FILE__, __LINE__, \
176 			 _("sect_index_rodata not initialized")), -1)	\
177       : objfile->sect_index_rodata)
178 
179 #define SECT_OFF_TEXT(objfile) \
180      ((objfile->sect_index_text == -1) \
181       ? (internal_error (__FILE__, __LINE__, \
182 			 _("sect_index_text not initialized")), -1)	\
183       : objfile->sect_index_text)
184 
185 /* Sometimes the .bss section is missing from the objfile, so we don't
186    want to die here.  Let the users of SECT_OFF_BSS deal with an
187    uninitialized section index.  */
188 #define SECT_OFF_BSS(objfile) (objfile)->sect_index_bss
189 
190 /* The "objstats" structure provides a place for gdb to record some
191    interesting information about its internal state at runtime, on a
192    per objfile basis, such as information about the number of symbols
193    read, size of string table (if any), etc.  */
194 
195 struct objstats
196 {
197   /* Number of partial symbols read.  */
198   int n_psyms = 0;
199 
200   /* Number of full symbols read.  */
201   int n_syms = 0;
202 
203   /* Number of ".stabs" read (if applicable).  */
204   int n_stabs = 0;
205 
206   /* Number of types.  */
207   int n_types = 0;
208 
209   /* Size of stringtable, (if applicable).  */
210   int sz_strtab = 0;
211 };
212 
213 #define OBJSTAT(objfile, expr) (objfile -> stats.expr)
214 #define OBJSTATS struct objstats stats
215 extern void print_objfile_statistics (void);
216 extern void print_symbol_bcache_statistics (void);
217 
218 /* Number of entries in the minimal symbol hash table.  */
219 #define MINIMAL_SYMBOL_HASH_SIZE 2039
220 
221 /* An iterator for minimal symbols.  */
222 
223 struct minimal_symbol_iterator
224 {
225   typedef minimal_symbol_iterator self_type;
226   typedef struct minimal_symbol *value_type;
227   typedef struct minimal_symbol *&reference;
228   typedef struct minimal_symbol **pointer;
229   typedef std::forward_iterator_tag iterator_category;
230   typedef int difference_type;
231 
232   explicit minimal_symbol_iterator (struct minimal_symbol *msym)
233     : m_msym (msym)
234   {
235   }
236 
237   value_type operator* () const
238   {
239     return m_msym;
240   }
241 
242   bool operator== (const self_type &other) const
243   {
244     return m_msym == other.m_msym;
245   }
246 
247   bool operator!= (const self_type &other) const
248   {
249     return m_msym != other.m_msym;
250   }
251 
252   self_type &operator++ ()
253   {
254     ++m_msym;
255     return *this;
256   }
257 
258 private:
259   struct minimal_symbol *m_msym;
260 };
261 
262 /* Some objfile data is hung off the BFD.  This enables sharing of the
263    data across all objfiles using the BFD.  The data is stored in an
264    instance of this structure, and associated with the BFD using the
265    registry system.  */
266 
267 struct objfile_per_bfd_storage
268 {
269   objfile_per_bfd_storage ()
270     : minsyms_read (false)
271   {}
272 
273   ~objfile_per_bfd_storage ();
274 
275   /* The storage has an obstack of its own.  */
276 
277   auto_obstack storage_obstack;
278 
279   /* String cache.  */
280 
281   gdb::bcache string_cache;
282 
283   /* The gdbarch associated with the BFD.  Note that this gdbarch is
284      determined solely from BFD information, without looking at target
285      information.  The gdbarch determined from a running target may
286      differ from this e.g. with respect to register types and names.  */
287 
288   struct gdbarch *gdbarch = NULL;
289 
290   /* Hash table for mapping symbol names to demangled names.  Each
291      entry in the hash table is a demangled_name_entry struct, storing the
292      language and two consecutive strings, both null-terminated; the first one
293      is a mangled or linkage name, and the second is the demangled name or just
294      a zero byte if the name doesn't demangle.  */
295 
296   htab_up demangled_names_hash;
297 
298   /* The per-objfile information about the entry point, the scope (file/func)
299      containing the entry point, and the scope of the user's main() func.  */
300 
301   entry_info ei {};
302 
303   /* The name and language of any "main" found in this objfile.  The
304      name can be NULL, which means that the information was not
305      recorded.  */
306 
307   const char *name_of_main = NULL;
308   enum language language_of_main = language_unknown;
309 
310   /* Each file contains a pointer to an array of minimal symbols for all
311      global symbols that are defined within the file.  The array is
312      terminated by a "null symbol", one that has a NULL pointer for the
313      name and a zero value for the address.  This makes it easy to walk
314      through the array when passed a pointer to somewhere in the middle
315      of it.  There is also a count of the number of symbols, which does
316      not include the terminating null symbol.  */
317 
318   gdb::unique_xmalloc_ptr<minimal_symbol> msymbols;
319   int minimal_symbol_count = 0;
320 
321   /* The number of minimal symbols read, before any minimal symbol
322      de-duplication is applied.  Note in particular that this has only
323      a passing relationship with the actual size of the table above;
324      use minimal_symbol_count if you need the true size.  */
325 
326   int n_minsyms = 0;
327 
328   /* This is true if minimal symbols have already been read.  Symbol
329      readers can use this to bypass minimal symbol reading.  Also, the
330      minimal symbol table management code in minsyms.c uses this to
331      suppress new minimal symbols.  You might think that MSYMBOLS or
332      MINIMAL_SYMBOL_COUNT could be used for this, but it is possible
333      for multiple readers to install minimal symbols into a given
334      per-BFD.  */
335 
336   bool minsyms_read : 1;
337 
338   /* This is a hash table used to index the minimal symbols by (mangled)
339      name.  */
340 
341   minimal_symbol *msymbol_hash[MINIMAL_SYMBOL_HASH_SIZE] {};
342 
343   /* This hash table is used to index the minimal symbols by their
344      demangled names.  Uses a language-specific hash function via
345      search_name_hash.  */
346 
347   minimal_symbol *msymbol_demangled_hash[MINIMAL_SYMBOL_HASH_SIZE] {};
348 
349   /* All the different languages of symbols found in the demangled
350      hash table.  */
351   std::bitset<nr_languages> demangled_hash_languages;
352 };
353 
354 /* An iterator that first returns a parent objfile, and then each
355    separate debug objfile.  */
356 
357 class separate_debug_iterator
358 {
359 public:
360 
361   explicit separate_debug_iterator (struct objfile *objfile)
362     : m_objfile (objfile),
363       m_parent (objfile)
364   {
365   }
366 
367   bool operator!= (const separate_debug_iterator &other)
368   {
369     return m_objfile != other.m_objfile;
370   }
371 
372   separate_debug_iterator &operator++ ();
373 
374   struct objfile *operator* ()
375   {
376     return m_objfile;
377   }
378 
379 private:
380 
381   struct objfile *m_objfile;
382   struct objfile *m_parent;
383 };
384 
385 /* A range adapter wrapping separate_debug_iterator.  */
386 
387 class separate_debug_range
388 {
389 public:
390 
391   explicit separate_debug_range (struct objfile *objfile)
392     : m_objfile (objfile)
393   {
394   }
395 
396   separate_debug_iterator begin ()
397   {
398     return separate_debug_iterator (m_objfile);
399   }
400 
401   separate_debug_iterator end ()
402   {
403     return separate_debug_iterator (nullptr);
404   }
405 
406 private:
407 
408   struct objfile *m_objfile;
409 };
410 
411 /* Master structure for keeping track of each file from which
412    gdb reads symbols.  There are several ways these get allocated: 1.
413    The main symbol file, symfile_objfile, set by the symbol-file command,
414    2.  Additional symbol files added by the add-symbol-file command,
415    3.  Shared library objfiles, added by ADD_SOLIB,  4.  symbol files
416    for modules that were loaded when GDB attached to a remote system
417    (see remote-vx.c).
418 
419    GDB typically reads symbols twice -- first an initial scan which just
420    reads "partial symbols"; these are partial information for the
421    static/global symbols in a symbol file.  When later looking up symbols,
422    objfile->sf->qf->lookup_symbol is used to check if we only have a partial
423    symbol and if so, read and expand the full compunit.  */
424 
425 struct objfile
426 {
427 private:
428 
429   /* The only way to create an objfile is to call objfile::make.  */
430   objfile (bfd *, const char *, objfile_flags);
431 
432 public:
433 
434   /* Normally you should not call delete.  Instead, call 'unlink' to
435      remove it from the program space's list.  In some cases, you may
436      need to hold a reference to an objfile that is independent of its
437      existence on the program space's list; for this case, the
438      destructor must be public so that shared_ptr can reference
439      it.  */
440   ~objfile ();
441 
442   /* Create an objfile.  */
443   static objfile *make (bfd *bfd_, const char *name_, objfile_flags flags_,
444 			objfile *parent = nullptr);
445 
446   /* Remove an objfile from the current program space, and free
447      it.  */
448   void unlink ();
449 
450   DISABLE_COPY_AND_ASSIGN (objfile);
451 
452   /* A range adapter that makes it possible to iterate over all
453      psymtabs in one objfile.  */
454 
455   psymtab_storage::partial_symtab_range psymtabs ()
456   {
457     return partial_symtabs->range ();
458   }
459 
460   /* Reset the storage for the partial symbol tables.  */
461 
462   void reset_psymtabs ()
463   {
464     psymbol_map.clear ();
465     partial_symtabs.reset (new psymtab_storage ());
466   }
467 
468   typedef next_adapter<struct compunit_symtab> compunits_range;
469 
470   /* A range adapter that makes it possible to iterate over all
471      compunits in one objfile.  */
472 
473   compunits_range compunits ()
474   {
475     return compunits_range (compunit_symtabs);
476   }
477 
478   /* A range adapter that makes it possible to iterate over all
479      minimal symbols of an objfile.  */
480 
481   class msymbols_range
482   {
483   public:
484 
485     explicit msymbols_range (struct objfile *objfile)
486       : m_objfile (objfile)
487     {
488     }
489 
490     minimal_symbol_iterator begin () const
491     {
492       return minimal_symbol_iterator (m_objfile->per_bfd->msymbols.get ());
493     }
494 
495     minimal_symbol_iterator end () const
496     {
497       return minimal_symbol_iterator
498 	(m_objfile->per_bfd->msymbols.get ()
499 	 + m_objfile->per_bfd->minimal_symbol_count);
500     }
501 
502   private:
503 
504     struct objfile *m_objfile;
505   };
506 
507   /* Return a range adapter for iterating over all minimal
508      symbols.  */
509 
510   msymbols_range msymbols ()
511   {
512     return msymbols_range (this);
513   }
514 
515   /* Return a range adapter for iterating over all the separate debug
516      objfiles of this objfile.  */
517 
518   separate_debug_range separate_debug_objfiles ()
519   {
520     return separate_debug_range (this);
521   }
522 
523   CORE_ADDR text_section_offset () const
524   {
525     return section_offsets[SECT_OFF_TEXT (this)];
526   }
527 
528   CORE_ADDR data_section_offset () const
529   {
530     return section_offsets[SECT_OFF_DATA (this)];
531   }
532 
533   /* Intern STRING and return the unique copy.  The copy has the same
534      lifetime as the per-BFD object.  */
535   const char *intern (const char *str)
536   {
537     return (const char *) per_bfd->string_cache.insert (str, strlen (str) + 1);
538   }
539 
540   /* Intern STRING and return the unique copy.  The copy has the same
541      lifetime as the per-BFD object.  */
542   const char *intern (const std::string &str)
543   {
544     return (const char *) per_bfd->string_cache.insert (str.c_str (),
545 							str.size () + 1);
546   }
547 
548   /* Retrieve the gdbarch associated with this objfile.  */
549   struct gdbarch *arch () const
550   {
551     return per_bfd->gdbarch;
552   }
553 
554 
555   /* The object file's original name as specified by the user,
556      made absolute, and tilde-expanded.  However, it is not canonicalized
557      (i.e., it has not been passed through gdb_realpath).
558      This pointer is never NULL.  This does not have to be freed; it is
559      guaranteed to have a lifetime at least as long as the objfile.  */
560 
561   const char *original_name = nullptr;
562 
563   CORE_ADDR addr_low = 0;
564 
565   /* Some flag bits for this objfile.  */
566 
567   objfile_flags flags;
568 
569   /* The program space associated with this objfile.  */
570 
571   struct program_space *pspace;
572 
573   /* List of compunits.
574      These are used to do symbol lookups and file/line-number lookups.  */
575 
576   struct compunit_symtab *compunit_symtabs = nullptr;
577 
578   /* The partial symbol tables.  */
579 
580   std::shared_ptr<psymtab_storage> partial_symtabs;
581 
582   /* The object file's BFD.  Can be null if the objfile contains only
583      minimal symbols, e.g. the run time common symbols for SunOS4.  */
584 
585   bfd *obfd;
586 
587   /* The per-BFD data.  Note that this is treated specially if OBFD
588      is NULL.  */
589 
590   struct objfile_per_bfd_storage *per_bfd = nullptr;
591 
592   /* The modification timestamp of the object file, as of the last time
593      we read its symbols.  */
594 
595   long mtime = 0;
596 
597   /* Obstack to hold objects that should be freed when we load a new symbol
598      table from this object file.  */
599 
600   struct obstack objfile_obstack {};
601 
602   /* Map symbol addresses to the partial symtab that defines the
603      object at that address.  */
604 
605   std::vector<std::pair<CORE_ADDR, partial_symtab *>> psymbol_map;
606 
607   /* Structure which keeps track of functions that manipulate objfile's
608      of the same type as this objfile.  I.e. the function to read partial
609      symbols for example.  Note that this structure is in statically
610      allocated memory, and is shared by all objfiles that use the
611      object module reader of this type.  */
612 
613   const struct sym_fns *sf = nullptr;
614 
615   /* Per objfile data-pointers required by other GDB modules.  */
616 
617   REGISTRY_FIELDS {};
618 
619   /* Set of relocation offsets to apply to each section.
620      The table is indexed by the_bfd_section->index, thus it is generally
621      as large as the number of sections in the binary.
622 
623      These offsets indicate that all symbols (including partial and
624      minimal symbols) which have been read have been relocated by this
625      much.  Symbols which are yet to be read need to be relocated by it.  */
626 
627   ::section_offsets section_offsets;
628 
629   /* Indexes in the section_offsets array.  These are initialized by the
630      *_symfile_offsets() family of functions (som_symfile_offsets,
631      xcoff_symfile_offsets, default_symfile_offsets).  In theory they
632      should correspond to the section indexes used by bfd for the
633      current objfile.  The exception to this for the time being is the
634      SOM version.
635 
636      These are initialized to -1 so that we can later detect if they
637      are used w/o being properly assigned to.  */
638 
639   int sect_index_text = -1;
640   int sect_index_data = -1;
641   int sect_index_bss = -1;
642   int sect_index_rodata = -1;
643 
644   /* These pointers are used to locate the section table, which
645      among other things, is used to map pc addresses into sections.
646      SECTIONS points to the first entry in the table, and
647      SECTIONS_END points to the first location past the last entry
648      in the table.  The table is stored on the objfile_obstack.  The
649      sections are indexed by the BFD section index; but the
650      structure data is only valid for certain sections
651      (e.g. non-empty, SEC_ALLOC).  */
652 
653   struct obj_section *sections = nullptr;
654   struct obj_section *sections_end = nullptr;
655 
656   /* GDB allows to have debug symbols in separate object files.  This is
657      used by .gnu_debuglink, ELF build id note and Mach-O OSO.
658      Although this is a tree structure, GDB only support one level
659      (ie a separate debug for a separate debug is not supported).  Note that
660      separate debug object are in the main chain and therefore will be
661      visited by objfiles & co iterators.  Separate debug objfile always
662      has a non-nul separate_debug_objfile_backlink.  */
663 
664   /* Link to the first separate debug object, if any.  */
665 
666   struct objfile *separate_debug_objfile = nullptr;
667 
668   /* If this is a separate debug object, this is used as a link to the
669      actual executable objfile.  */
670 
671   struct objfile *separate_debug_objfile_backlink = nullptr;
672 
673   /* If this is a separate debug object, this is a link to the next one
674      for the same executable objfile.  */
675 
676   struct objfile *separate_debug_objfile_link = nullptr;
677 
678   /* Place to stash various statistics about this objfile.  */
679 
680   OBJSTATS;
681 
682   /* A linked list of symbols created when reading template types or
683      function templates.  These symbols are not stored in any symbol
684      table, so we have to keep them here to relocate them
685      properly.  */
686 
687   struct symbol *template_symbols = nullptr;
688 
689   /* Associate a static link (struct dynamic_prop *) to all blocks (struct
690      block *) that have one.
691 
692      In the context of nested functions (available in Pascal, Ada and GNU C,
693      for instance), a static link (as in DWARF's DW_AT_static_link attribute)
694      for a function is a way to get the frame corresponding to the enclosing
695      function.
696 
697      Very few blocks have a static link, so it's more memory efficient to
698      store these here rather than in struct block.  Static links must be
699      allocated on the objfile's obstack.  */
700   htab_up static_links;
701 
702   /* JIT-related data for this objfile, if the objfile is a JITer;
703      that is, it produces JITed objfiles.  */
704   std::unique_ptr<jiter_objfile_data> jiter_data = nullptr;
705 
706   /* JIT-related data for this objfile, if the objfile is JITed;
707      that is, it was produced by a JITer.  */
708   std::unique_ptr<jited_objfile_data> jited_data = nullptr;
709 
710   /* A flag that is set to true if the JIT interface symbols are not
711      found in this objfile, so that we can skip the symbol lookup the
712      next time.  If an objfile does not have the symbols, it will
713      never have them.  */
714   bool skip_jit_symbol_lookup = false;
715 };
716 
717 /* A deleter for objfile.  */
718 
719 struct objfile_deleter
720 {
721   void operator() (objfile *ptr) const
722   {
723     ptr->unlink ();
724   }
725 };
726 
727 /* A unique pointer that holds an objfile.  */
728 
729 typedef std::unique_ptr<objfile, objfile_deleter> objfile_up;
730 
731 /* Declarations for functions defined in objfiles.c */
732 
733 extern int entry_point_address_query (CORE_ADDR *entry_p);
734 
735 extern CORE_ADDR entry_point_address (void);
736 
737 extern void build_objfile_section_table (struct objfile *);
738 
739 extern void free_objfile_separate_debug (struct objfile *);
740 
741 extern void objfile_relocate (struct objfile *, const section_offsets &);
742 extern void objfile_rebase (struct objfile *, CORE_ADDR);
743 
744 extern int objfile_has_partial_symbols (struct objfile *objfile);
745 
746 extern int objfile_has_full_symbols (struct objfile *objfile);
747 
748 extern int objfile_has_symbols (struct objfile *objfile);
749 
750 extern int have_partial_symbols (void);
751 
752 extern int have_full_symbols (void);
753 
754 extern void objfile_set_sym_fns (struct objfile *objfile,
755 				 const struct sym_fns *sf);
756 
757 extern void objfiles_changed (void);
758 
759 /* Return true if ADDR maps into one of the sections of OBJFILE and false
760    otherwise.  */
761 
762 extern bool is_addr_in_objfile (CORE_ADDR addr, const struct objfile *objfile);
763 
764 /* Return true if ADDRESS maps into one of the sections of a
765    OBJF_SHARED objfile of PSPACE and false otherwise.  */
766 
767 extern bool shared_objfile_contains_address_p (struct program_space *pspace,
768                                                CORE_ADDR address);
769 
770 /* This operation deletes all objfile entries that represent solibs that
771    weren't explicitly loaded by the user, via e.g., the add-symbol-file
772    command.  */
773 
774 extern void objfile_purge_solibs (void);
775 
776 /* Functions for dealing with the minimal symbol table, really a misc
777    address<->symbol mapping for things we don't have debug symbols for.  */
778 
779 extern int have_minimal_symbols (void);
780 
781 extern struct obj_section *find_pc_section (CORE_ADDR pc);
782 
783 /* Return non-zero if PC is in a section called NAME.  */
784 extern int pc_in_section (CORE_ADDR, const char *);
785 
786 /* Return non-zero if PC is in a SVR4-style procedure linkage table
787    section.  */
788 
789 static inline int
790 in_plt_section (CORE_ADDR pc)
791 {
792   return pc_in_section (pc, ".plt");
793 }
794 
795 /* Keep a registry of per-objfile data-pointers required by other GDB
796    modules.  */
797 DECLARE_REGISTRY(objfile);
798 
799 /* In normal use, the section map will be rebuilt by find_pc_section
800    if objfiles have been added, removed or relocated since it was last
801    called.  Calling inhibit_section_map_updates will inhibit this
802    behavior until the returned scoped_restore object is destroyed.  If
803    you call inhibit_section_map_updates you must ensure that every
804    call to find_pc_section in the inhibited region relates to a
805    section that is already in the section map and has not since been
806    removed or relocated.  */
807 extern scoped_restore_tmpl<int> inhibit_section_map_updates
808     (struct program_space *pspace);
809 
810 extern void default_iterate_over_objfiles_in_search_order
811   (struct gdbarch *gdbarch,
812    iterate_over_objfiles_in_search_order_cb_ftype *cb,
813    void *cb_data, struct objfile *current_objfile);
814 
815 /* Reset the per-BFD storage area on OBJ.  */
816 
817 void set_objfile_per_bfd (struct objfile *obj);
818 
819 /* Return canonical name for OBJFILE.
820    This is the real file name if the file has been opened.
821    Otherwise it is the original name supplied by the user.  */
822 
823 const char *objfile_name (const struct objfile *objfile);
824 
825 /* Return the (real) file name of OBJFILE if the file has been opened,
826    otherwise return NULL.  */
827 
828 const char *objfile_filename (const struct objfile *objfile);
829 
830 /* Return the name to print for OBJFILE in debugging messages.  */
831 
832 extern const char *objfile_debug_name (const struct objfile *objfile);
833 
834 /* Return the name of the file format of OBJFILE if the file has been opened,
835    otherwise return NULL.  */
836 
837 const char *objfile_flavour_name (struct objfile *objfile);
838 
839 /* Set the objfile's notion of the "main" name and language.  */
840 
841 extern void set_objfile_main_name (struct objfile *objfile,
842 				   const char *name, enum language lang);
843 
844 extern void objfile_register_static_link
845   (struct objfile *objfile,
846    const struct block *block,
847    const struct dynamic_prop *static_link);
848 
849 extern const struct dynamic_prop *objfile_lookup_static_link
850   (struct objfile *objfile, const struct block *block);
851 
852 #endif /* !defined (OBJFILES_H) */
853