gdb/objfiles.h

   1 /* Definitions for symbol file management in GDB.
   2
   3    Copyright (C) 1992-2013 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 relocated value we should use for this objfile entry point.  */
 105     CORE_ADDR entry_point;
 106
 107     /* Set to 1 iff ENTRY_POINT contains a valid value.  */
 108     unsigned entry_point_p : 1;
 109   };
 110
 111 /* Sections in an objfile.  The section offsets are stored in the
 112    OBJFILE.  */
 113
 114 struct obj_section
 115   {
 116     struct bfd_section *the_bfd_section;        /* BFD section pointer */
 117
 118     /* Objfile this section is part of.  */
 119     struct objfile *objfile;
 120
 121     /* True if this "overlay section" is mapped into an "overlay region".  */
 122     int ovly_mapped;
 123   };
 124
 125 /* Relocation offset applied to S.  */
 126 #define obj_section_offset(s)                                           \
 127   (((s)->objfile->section_offsets)->offsets[gdb_bfd_section_index ((s)->objfile->obfd, (s)->the_bfd_section)])
 128
 129 /* The memory address of section S (vma + offset).  */
 130 #define obj_section_addr(s)                                             \
 131   (bfd_get_section_vma ((s)->objfile->obfd, s->the_bfd_section)         \
 132    + obj_section_offset (s))
 133
 134 /* The one-passed-the-end memory address of section S
 135    (vma + size + offset).  */
 136 #define obj_section_endaddr(s)                                          \
 137   (bfd_get_section_vma ((s)->objfile->obfd, s->the_bfd_section)         \
 138    + bfd_get_section_size ((s)->the_bfd_section)                        \
 139    + obj_section_offset (s))
 140
 141 /* The "objstats" structure provides a place for gdb to record some
 142    interesting information about its internal state at runtime, on a
 143    per objfile basis, such as information about the number of symbols
 144    read, size of string table (if any), etc.  */
 145
 146 struct objstats
 147   {
 148     int n_minsyms;              /* Number of minimal symbols read */
 149     int n_psyms;                /* Number of partial symbols read */
 150     int n_syms;                 /* Number of full symbols read */
 151     int n_stabs;                /* Number of ".stabs" read (if applicable) */
 152     int n_types;                /* Number of types */
 153     int sz_strtab;              /* Size of stringtable, (if applicable) */
 154   };
 155
 156 #define OBJSTAT(objfile, expr) (objfile -> stats.expr)
 157 #define OBJSTATS struct objstats stats
 158 extern void print_objfile_statistics (void);
 159 extern void print_symbol_bcache_statistics (void);
 160
 161 /* Number of entries in the minimal symbol hash table.  */
 162 #define MINIMAL_SYMBOL_HASH_SIZE 2039
 163
 164 /* Some objfile data is hung off the BFD.  This enables sharing of the
 165    data across all objfiles using the BFD.  The data is stored in an
 166    instance of this structure, and associated with the BFD using the
 167    registry system.  */
 168
 169 struct objfile_per_bfd_storage
 170 {
 171   /* The storage has an obstack of its own.  */
 172
 173   struct obstack storage_obstack;
 174
 175   /* Byte cache for file names.  */
 176
 177   struct bcache *filename_cache;
 178
 179   /* Byte cache for macros.  */
 180   struct bcache *macro_cache;
 181 };
 182
 183 /* Master structure for keeping track of each file from which
 184    gdb reads symbols.  There are several ways these get allocated: 1.
 185    The main symbol file, symfile_objfile, set by the symbol-file command,
 186    2.  Additional symbol files added by the add-symbol-file command,
 187    3.  Shared library objfiles, added by ADD_SOLIB,  4.  symbol files
 188    for modules that were loaded when GDB attached to a remote system
 189    (see remote-vx.c).  */
 190
 191 struct objfile
 192   {
 193
 194     /* All struct objfile's are chained together by their next pointers.
 195        The program space field "objfiles"  (frequently referenced via
 196        the macro "object_files") points to the first link in this
 197        chain.  */
 198
 199     struct objfile *next;
 200
 201     /* The object file's name, tilde-expanded and absolute.  This
 202        pointer is never NULL.  This does not have to be freed; it is
 203        guaranteed to have a lifetime at least as long as the objfile.  */
 204
 205     char *name;
 206
 207     CORE_ADDR addr_low;
 208
 209     /* Some flag bits for this objfile.
 210        The values are defined by OBJF_*.  */
 211
 212     unsigned short flags;
 213
 214     /* The program space associated with this objfile.  */
 215
 216     struct program_space *pspace;
 217
 218     /* Each objfile points to a linked list of symtabs derived from this file,
 219        one symtab structure for each compilation unit (source file).  Each link
 220        in the symtab list contains a backpointer to this objfile.  */
 221
 222     struct symtab *symtabs;
 223
 224     /* Each objfile points to a linked list of partial symtabs derived from
 225        this file, one partial symtab structure for each compilation unit
 226        (source file).  */
 227
 228     struct partial_symtab *psymtabs;
 229
 230     /* Map addresses to the entries of PSYMTABS.  It would be more efficient to
 231        have a map per the whole process but ADDRMAP cannot selectively remove
 232        its items during FREE_OBJFILE.  This mapping is already present even for
 233        PARTIAL_SYMTABs which still have no corresponding full SYMTABs read.  */
 234
 235     struct addrmap *psymtabs_addrmap;
 236
 237     /* List of freed partial symtabs, available for re-use.  */
 238
 239     struct partial_symtab *free_psymtabs;
 240
 241     /* The object file's BFD.  Can be null if the objfile contains only
 242        minimal symbols, e.g. the run time common symbols for SunOS4.  */
 243
 244     bfd *obfd;
 245
 246     /* The per-BFD data.  Note that this is treated specially if OBFD
 247        is NULL.  */
 248
 249     struct objfile_per_bfd_storage *per_bfd;
 250
 251     /* The gdbarch associated with the BFD.  Note that this gdbarch is
 252        determined solely from BFD information, without looking at target
 253        information.  The gdbarch determined from a running target may
 254        differ from this e.g. with respect to register types and names.  */
 255
 256     struct gdbarch *gdbarch;
 257
 258     /* The modification timestamp of the object file, as of the last time
 259        we read its symbols.  */
 260
 261     long mtime;
 262
 263     /* Obstack to hold objects that should be freed when we load a new symbol
 264        table from this object file.  */
 265
 266     struct obstack objfile_obstack;
 267
 268     /* A byte cache where we can stash arbitrary "chunks" of bytes that
 269        will not change.  */
 270
 271     struct psymbol_bcache *psymbol_cache; /* Byte cache for partial syms.  */
 272
 273     /* Hash table for mapping symbol names to demangled names.  Each
 274        entry in the hash table is actually two consecutive strings,
 275        both null-terminated; the first one is a mangled or linkage
 276        name, and the second is the demangled name or just a zero byte
 277        if the name doesn't demangle.  */
 278     struct htab *demangled_names_hash;
 279
 280     /* Vectors of all partial symbols read in from file.  The actual data
 281        is stored in the objfile_obstack.  */
 282
 283     struct psymbol_allocation_list global_psymbols;
 284     struct psymbol_allocation_list static_psymbols;
 285
 286     /* Each file contains a pointer to an array of minimal symbols for all
 287        global symbols that are defined within the file.  The array is
 288        terminated by a "null symbol", one that has a NULL pointer for the
 289        name and a zero value for the address.  This makes it easy to walk
 290        through the array when passed a pointer to somewhere in the middle
 291        of it.  There is also a count of the number of symbols, which does
 292        not include the terminating null symbol.  The array itself, as well
 293        as all the data that it points to, should be allocated on the
 294        objfile_obstack for this file.  */
 295
 296     struct minimal_symbol *msymbols;
 297     int minimal_symbol_count;
 298
 299     /* This is a hash table used to index the minimal symbols by name.  */
 300
 301     struct minimal_symbol *msymbol_hash[MINIMAL_SYMBOL_HASH_SIZE];
 302
 303     /* This hash table is used to index the minimal symbols by their
 304        demangled names.  */
 305
 306     struct minimal_symbol *msymbol_demangled_hash[MINIMAL_SYMBOL_HASH_SIZE];
 307
 308     /* Structure which keeps track of functions that manipulate objfile's
 309        of the same type as this objfile.  I.e. the function to read partial
 310        symbols for example.  Note that this structure is in statically
 311        allocated memory, and is shared by all objfiles that use the
 312        object module reader of this type.  */
 313
 314     const struct sym_fns *sf;
 315
 316     /* The per-objfile information about the entry point, the scope (file/func)
 317        containing the entry point, and the scope of the user's main() func.  */
 318
 319     struct entry_info ei;
 320
 321     /* Per objfile data-pointers required by other GDB modules.  */
 322
 323     REGISTRY_FIELDS;
 324
 325     /* Set of relocation offsets to apply to each section.
 326        The table is indexed by the_bfd_section->index, thus it is generally
 327        as large as the number of sections in the binary.
 328        The table is stored on the objfile_obstack.
 329
 330        These offsets indicate that all symbols (including partial and
 331        minimal symbols) which have been read have been relocated by this
 332        much.  Symbols which are yet to be read need to be relocated by it.  */
 333
 334     struct section_offsets *section_offsets;
 335     int num_sections;
 336
 337     /* Indexes in the section_offsets array.  These are initialized by the
 338        *_symfile_offsets() family of functions (som_symfile_offsets,
 339        xcoff_symfile_offsets, default_symfile_offsets).  In theory they
 340        should correspond to the section indexes used by bfd for the
 341        current objfile.  The exception to this for the time being is the
 342        SOM version.  */
 343
 344     int sect_index_text;
 345     int sect_index_data;
 346     int sect_index_bss;
 347     int sect_index_rodata;
 348
 349     /* These pointers are used to locate the section table, which
 350        among other things, is used to map pc addresses into sections.
 351        SECTIONS points to the first entry in the table, and
 352        SECTIONS_END points to the first location past the last entry
 353        in the table.  The table is stored on the objfile_obstack.  The
 354        sections are indexed by the BFD section index; but the
 355        structure data is only valid for certain sections
 356        (e.g. non-empty, SEC_ALLOC).  */
 357
 358     struct obj_section *sections, *sections_end;
 359
 360     /* GDB allows to have debug symbols in separate object files.  This is
 361        used by .gnu_debuglink, ELF build id note and Mach-O OSO.
 362        Although this is a tree structure, GDB only support one level
 363        (ie a separate debug for a separate debug is not supported).  Note that
 364        separate debug object are in the main chain and therefore will be
 365        visited by ALL_OBJFILES & co iterators.  Separate debug objfile always
 366        has a non-nul separate_debug_objfile_backlink.  */
 367
 368     /* Link to the first separate debug object, if any.  */
 369     struct objfile *separate_debug_objfile;
 370
 371     /* If this is a separate debug object, this is used as a link to the
 372        actual executable objfile.  */
 373     struct objfile *separate_debug_objfile_backlink;
 374
 375     /* If this is a separate debug object, this is a link to the next one
 376        for the same executable objfile.  */
 377     struct objfile *separate_debug_objfile_link;
 378
 379     /* Place to stash various statistics about this objfile.  */
 380     OBJSTATS;
 381
 382     /* A linked list of symbols created when reading template types or
 383        function templates.  These symbols are not stored in any symbol
 384        table, so we have to keep them here to relocate them
 385        properly.  */
 386     struct symbol *template_symbols;
 387   };
 388
 389 /* Defines for the objfile flag word.  */
 390
 391 /* When an object file has its functions reordered (currently Irix-5.2
 392    shared libraries exhibit this behaviour), we will need an expensive
 393    algorithm to locate a partial symtab or symtab via an address.
 394    To avoid this penalty for normal object files, we use this flag,
 395    whose setting is determined upon symbol table read in.  */
 396
 397 #define OBJF_REORDERED  (1 << 0)        /* Functions are reordered */
 398
 399 /* Distinguish between an objfile for a shared library and a "vanilla"
 400    objfile.  (If not set, the objfile may still actually be a solib.
 401    This can happen if the user created the objfile by using the
 402    add-symbol-file command.  GDB doesn't in that situation actually
 403    check whether the file is a solib.  Rather, the target's
 404    implementation of the solib interface is responsible for setting
 405    this flag when noticing solibs used by an inferior.)  */
 406
 407 #define OBJF_SHARED     (1 << 1)        /* From a shared library */
 408
 409 /* User requested that this objfile be read in it's entirety.  */
 410
 411 #define OBJF_READNOW    (1 << 2)        /* Immediate full read */
 412
 413 /* This objfile was created because the user explicitly caused it
 414    (e.g., used the add-symbol-file command).  This bit offers a way
 415    for run_command to remove old objfile entries which are no longer
 416    valid (i.e., are associated with an old inferior), but to preserve
 417    ones that the user explicitly loaded via the add-symbol-file
 418    command.  */
 419
 420 #define OBJF_USERLOADED (1 << 3)        /* User loaded */
 421
 422 /* Set if we have tried to read partial symtabs for this objfile.
 423    This is used to allow lazy reading of partial symtabs.  */
 424
 425 #define OBJF_PSYMTABS_READ (1 << 4)
 426
 427 /* Set if this is the main symbol file
 428    (as opposed to symbol file for dynamically loaded code).  */
 429
 430 #define OBJF_MAINLINE (1 << 5)
 431
 432 /* The object file that contains the runtime common minimal symbols
 433    for SunOS4.  Note that this objfile has no associated BFD.  */
 434
 435 extern struct objfile *rt_common_objfile;
 436
 437 /* Declarations for functions defined in objfiles.c */
 438
 439 extern struct objfile *allocate_objfile (bfd *, int);
 440
 441 extern struct gdbarch *get_objfile_arch (struct objfile *);
 442
 443 extern int entry_point_address_query (CORE_ADDR *entry_p);
 444
 445 extern CORE_ADDR entry_point_address (void);
 446
 447 extern void build_objfile_section_table (struct objfile *);
 448
 449 extern void terminate_minimal_symbol_table (struct objfile *objfile);
 450
 451 extern struct objfile *objfile_separate_debug_iterate (const struct objfile *,
 452                                                        const struct objfile *);
 453
 454 extern void put_objfile_before (struct objfile *, struct objfile *);
 455
 456 extern void objfile_to_front (struct objfile *);
 457
 458 extern void add_separate_debug_objfile (struct objfile *, struct objfile *);
 459
 460 extern void unlink_objfile (struct objfile *);
 461
 462 extern void free_objfile (struct objfile *);
 463
 464 extern void free_objfile_separate_debug (struct objfile *);
 465
 466 extern struct cleanup *make_cleanup_free_objfile (struct objfile *);
 467
 468 extern void free_all_objfiles (void);
 469
 470 extern void objfile_relocate (struct objfile *, const struct section_offsets *);
 471 extern void objfile_rebase (struct objfile *, CORE_ADDR);
 472
 473 extern int objfile_has_partial_symbols (struct objfile *objfile);
 474
 475 extern int objfile_has_full_symbols (struct objfile *objfile);
 476
 477 extern int objfile_has_symbols (struct objfile *objfile);
 478
 479 extern int have_partial_symbols (void);
 480
 481 extern int have_full_symbols (void);
 482
 483 extern void objfiles_changed (void);
 484
 485 /* This operation deletes all objfile entries that represent solibs that
 486    weren't explicitly loaded by the user, via e.g., the add-symbol-file
 487    command.  */
 488
 489 extern void objfile_purge_solibs (void);
 490
 491 /* Functions for dealing with the minimal symbol table, really a misc
 492    address<->symbol mapping for things we don't have debug symbols for.  */
 493
 494 extern int have_minimal_symbols (void);
 495
 496 extern struct obj_section *find_pc_section (CORE_ADDR pc);
 497
 498 extern int in_plt_section (CORE_ADDR, char *);
 499
 500 /* Keep a registry of per-objfile data-pointers required by other GDB
 501    modules.  */
 502 DECLARE_REGISTRY(objfile);
 503
 504 /* In normal use, the section map will be rebuilt by find_pc_section
 505    if objfiles have been added, removed or relocated since it was last
 506    called.  Calling inhibit_section_map_updates will inhibit this
 507    behavior until resume_section_map_updates is called.  If you call
 508    inhibit_section_map_updates you must ensure that every call to
 509    find_pc_section in the inhibited region relates to a section that
 510    is already in the section map and has not since been removed or
 511    relocated.  */
 512 extern void inhibit_section_map_updates (struct program_space *pspace);
 513
 514 /* Resume automatically rebuilding the section map as required.  */
 515 extern void resume_section_map_updates (struct program_space *pspace);
 516
 517 /* Version of the above suitable for use as a cleanup.  */
 518 extern void resume_section_map_updates_cleanup (void *arg);
 519
 520 extern void default_iterate_over_objfiles_in_search_order
 521   (struct gdbarch *gdbarch,
 522    iterate_over_objfiles_in_search_order_cb_ftype *cb,
 523    void *cb_data, struct objfile *current_objfile);
 524 \f
 525
 526 /* Traverse all object files in the current program space.
 527    ALL_OBJFILES_SAFE works even if you delete the objfile during the
 528    traversal.  */
 529
 530 /* Traverse all object files in program space SS.  */
 531
 532 #define ALL_PSPACE_OBJFILES(ss, obj)                                    \
 533   for ((obj) = ss->objfiles; (obj) != NULL; (obj) = (obj)->next)
 534
 535 #define ALL_PSPACE_OBJFILES_SAFE(ss, obj, nxt)          \
 536   for ((obj) = ss->objfiles;                    \
 537        (obj) != NULL? ((nxt)=(obj)->next,1) :0; \
 538        (obj) = (nxt))
 539
 540 #define ALL_OBJFILES(obj)                           \
 541   for ((obj) = current_program_space->objfiles; \
 542        (obj) != NULL;                               \
 543        (obj) = (obj)->next)
 544
 545 #define ALL_OBJFILES_SAFE(obj,nxt)                      \
 546   for ((obj) = current_program_space->objfiles; \
 547        (obj) != NULL? ((nxt)=(obj)->next,1) :0; \
 548        (obj) = (nxt))
 549
 550 /* Traverse all symtabs in one objfile.  */
 551
 552 #define ALL_OBJFILE_SYMTABS(objfile, s) \
 553     for ((s) = (objfile) -> symtabs; (s) != NULL; (s) = (s) -> next)
 554
 555 /* Traverse all primary symtabs in one objfile.  */
 556
 557 #define ALL_OBJFILE_PRIMARY_SYMTABS(objfile, s) \
 558   ALL_OBJFILE_SYMTABS ((objfile), (s)) \
 559     if ((s)->primary)
 560
 561 /* Traverse all minimal symbols in one objfile.  */
 562
 563 #define ALL_OBJFILE_MSYMBOLS(objfile, m) \
 564     for ((m) = (objfile) -> msymbols; SYMBOL_LINKAGE_NAME(m) != NULL; (m)++)
 565
 566 /* Traverse all symtabs in all objfiles in the current symbol
 567    space.  */
 568
 569 #define ALL_SYMTABS(objfile, s) \
 570   ALL_OBJFILES (objfile)         \
 571     ALL_OBJFILE_SYMTABS (objfile, s)
 572
 573 #define ALL_PSPACE_SYMTABS(ss, objfile, s)              \
 574   ALL_PSPACE_OBJFILES (ss, objfile)                     \
 575     ALL_OBJFILE_SYMTABS (objfile, s)
 576
 577 /* Traverse all symtabs in all objfiles in the current program space,
 578    skipping included files (which share a blockvector with their
 579    primary symtab).  */
 580
 581 #define ALL_PRIMARY_SYMTABS(objfile, s) \
 582   ALL_OBJFILES (objfile)                \
 583     ALL_OBJFILE_PRIMARY_SYMTABS (objfile, s)
 584
 585 #define ALL_PSPACE_PRIMARY_SYMTABS(pspace, objfile, s)  \
 586   ALL_PSPACE_OBJFILES (ss, objfile)                     \
 587     ALL_OBJFILE_PRIMARY_SYMTABS (objfile, s)
 588
 589 /* Traverse all minimal symbols in all objfiles in the current symbol
 590    space.  */
 591
 592 #define ALL_MSYMBOLS(objfile, m) \
 593   ALL_OBJFILES (objfile)         \
 594     ALL_OBJFILE_MSYMBOLS (objfile, m)
 595
 596 #define ALL_OBJFILE_OSECTIONS(objfile, osect)   \
 597   for (osect = objfile->sections; osect < objfile->sections_end; osect++) \
 598     if (osect->the_bfd_section == NULL)                                 \
 599       {                                                                 \
 600         /* Nothing.  */                                                 \
 601       }                                                                 \
 602     else
 603
 604 /* Traverse all obj_sections in all objfiles in the current program
 605    space.
 606
 607    Note that this detects a "break" in the inner loop, and exits
 608    immediately from the outer loop as well, thus, client code doesn't
 609    need to know that this is implemented with a double for.  The extra
 610    hair is to make sure that a "break;" stops the outer loop iterating
 611    as well, and both OBJFILE and OSECT are left unmodified:
 612
 613     - The outer loop learns about the inner loop's end condition, and
 614       stops iterating if it detects the inner loop didn't reach its
 615       end.  In other words, the outer loop keeps going only if the
 616       inner loop reached its end cleanly [(osect) ==
 617       (objfile)->sections_end].
 618
 619     - OSECT is initialized in the outer loop initialization
 620       expressions, such as if the inner loop has reached its end, so
 621       the check mentioned above succeeds the first time.
 622
 623     - The trick to not clearing OBJFILE on a "break;" is, in the outer
 624       loop's loop expression, advance OBJFILE, but iff the inner loop
 625       reached its end.  If not, there was a "break;", so leave OBJFILE
 626       as is; the outer loop's conditional will break immediately as
 627       well (as OSECT will be different from OBJFILE->sections_end).  */
 628
 629 #define ALL_OBJSECTIONS(objfile, osect)                                 \
 630   for ((objfile) = current_program_space->objfiles,                     \
 631          (objfile) != NULL ? ((osect) = (objfile)->sections_end) : 0;   \
 632        (objfile) != NULL                                                \
 633          && (osect) == (objfile)->sections_end;                         \
 634        ((osect) == (objfile)->sections_end                              \
 635         ? ((objfile) = (objfile)->next,                                 \
 636            (objfile) != NULL ? (osect) = (objfile)->sections_end : 0)   \
 637         : 0))                                                           \
 638     ALL_OBJFILE_OSECTIONS (objfile, osect)
 639
 640 #define SECT_OFF_DATA(objfile) \
 641      ((objfile->sect_index_data == -1) \
 642       ? (internal_error (__FILE__, __LINE__, \
 643                          _("sect_index_data not initialized")), -1)     \
 644       : objfile->sect_index_data)
 645
 646 #define SECT_OFF_RODATA(objfile) \
 647      ((objfile->sect_index_rodata == -1) \
 648       ? (internal_error (__FILE__, __LINE__, \
 649                          _("sect_index_rodata not initialized")), -1)   \
 650       : objfile->sect_index_rodata)
 651
 652 #define SECT_OFF_TEXT(objfile) \
 653      ((objfile->sect_index_text == -1) \
 654       ? (internal_error (__FILE__, __LINE__, \
 655                          _("sect_index_text not initialized")), -1)     \
 656       : objfile->sect_index_text)
 657
 658 /* Sometimes the .bss section is missing from the objfile, so we don't
 659    want to die here.  Let the users of SECT_OFF_BSS deal with an
 660    uninitialized section index.  */
 661 #define SECT_OFF_BSS(objfile) (objfile)->sect_index_bss
 662
 663 /* Answer whether there is more than one object file loaded.  */
 664
 665 #define MULTI_OBJFILE_P() (object_files && object_files->next)
 666
 667 /* Reset the per-BFD storage area on OBJ.  */
 668
 669 void set_objfile_per_bfd (struct objfile *obj);
 670
 671 #endif /* !defined (OBJFILES_H) */