gdb/objfiles.h

   1 /* Definitions for symbol file management in GDB.
   2
   3    Copyright (C) 1992-2004, 2007-2012 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
  27 struct bcache;
  28 struct htab;
  29 struct symtab;
  30 struct objfile_data;
  31
  32 /* This structure maintains information on a per-objfile basis about the
  33    "entry point" of the objfile, and the scope within which the entry point
  34    exists.  It is possible that gdb will see more than one objfile that is
  35    executable, each with its own entry point.
  36
  37    For example, for dynamically linked executables in SVR4, the dynamic linker
  38    code is contained within the shared C library, which is actually executable
  39    and is run by the kernel first when an exec is done of a user executable
  40    that is dynamically linked.  The dynamic linker within the shared C library
  41    then maps in the various program segments in the user executable and jumps
  42    to the user executable's recorded entry point, as if the call had been made
  43    directly by the kernel.
  44
  45    The traditional gdb method of using this info was to use the
  46    recorded entry point to set the entry-file's lowpc and highpc from
  47    the debugging information, where these values are the starting
  48    address (inclusive) and ending address (exclusive) of the
  49    instruction space in the executable which correspond to the
  50    "startup file", i.e. crt0.o in most cases.  This file is assumed to
  51    be a startup file and frames with pc's inside it are treated as
  52    nonexistent.  Setting these variables is necessary so that
  53    backtraces do not fly off the bottom of the stack.
  54
  55    NOTE: cagney/2003-09-09: It turns out that this "traditional"
  56    method doesn't work.  Corinna writes: ``It turns out that the call
  57    to test for "inside entry file" destroys a meaningful backtrace
  58    under some conditions.  E.g. the backtrace tests in the asm-source
  59    testcase are broken for some targets.  In this test the functions
  60    are all implemented as part of one file and the testcase is not
  61    necessarily linked with a start file (depending on the target).
  62    What happens is, that the first frame is printed normaly and
  63    following frames are treated as being inside the enttry file then.
  64    This way, only the #0 frame is printed in the backtrace output.''
  65    Ref "frame.c" "NOTE: vinschen/2003-04-01".
  66
  67    Gdb also supports an alternate method to avoid running off the bottom
  68    of the stack.
  69
  70    There are two frames that are "special", the frame for the function
  71    containing the process entry point, since it has no predecessor frame,
  72    and the frame for the function containing the user code entry point
  73    (the main() function), since all the predecessor frames are for the
  74    process startup code.  Since we have no guarantee that the linked
  75    in startup modules have any debugging information that gdb can use,
  76    we need to avoid following frame pointers back into frames that might
  77    have been built in the startup code, as we might get hopelessly
  78    confused.  However, we almost always have debugging information
  79    available for main().
  80
  81    These variables are used to save the range of PC values which are
  82    valid within the main() function and within the function containing
  83    the process entry point.  If we always consider the frame for
  84    main() as the outermost frame when debugging user code, and the
  85    frame for the process entry point function as the outermost frame
  86    when debugging startup code, then all we have to do is have
  87    DEPRECATED_FRAME_CHAIN_VALID return false whenever a frame's
  88    current PC is within the range specified by these variables.  In
  89    essence, we set "ceilings" in the frame chain beyond which we will
  90    not proceed when following the frame chain back up the stack.
  91
  92    A nice side effect is that we can still debug startup code without
  93    running off the end of the frame chain, assuming that we have usable
  94    debugging information in the startup modules, and if we choose to not
  95    use the block at main, or can't find it for some reason, everything
  96    still works as before.  And if we have no startup code debugging
  97    information but we do have usable information for main(), backtraces
  98    from user code don't go wandering off into the startup code.  */
  99
 100 struct entry_info
 101   {
 102     /* The relocated value we should use for this objfile entry point.  */
 103     CORE_ADDR entry_point;
 104
 105     /* Set to 1 iff ENTRY_POINT contains a valid value.  */
 106     unsigned entry_point_p : 1;
 107   };
 108
 109 /* Sections in an objfile.  The section offsets are stored in the
 110    OBJFILE.  */
 111
 112 struct obj_section
 113   {
 114     struct bfd_section *the_bfd_section;        /* BFD section pointer */
 115
 116     /* Objfile this section is part of.  */
 117     struct objfile *objfile;
 118
 119     /* True if this "overlay section" is mapped into an "overlay region".  */
 120     int ovly_mapped;
 121   };
 122
 123 /* Relocation offset applied to S.  */
 124 #define obj_section_offset(s)                                           \
 125   (((s)->objfile->section_offsets)->offsets[(s)->the_bfd_section->index])
 126
 127 /* The memory address of section S (vma + offset).  */
 128 #define obj_section_addr(s)                                             \
 129   (bfd_get_section_vma ((s)->objfile->obfd, s->the_bfd_section)         \
 130    + obj_section_offset (s))
 131
 132 /* The one-passed-the-end memory address of section S
 133    (vma + size + offset).  */
 134 #define obj_section_endaddr(s)                                          \
 135   (bfd_get_section_vma ((s)->objfile->obfd, s->the_bfd_section)         \
 136    + bfd_get_section_size ((s)->the_bfd_section)                        \
 137    + obj_section_offset (s))
 138
 139 /* The "objstats" structure provides a place for gdb to record some
 140    interesting information about its internal state at runtime, on a
 141    per objfile basis, such as information about the number of symbols
 142    read, size of string table (if any), etc.  */
 143
 144 struct objstats
 145   {
 146     int n_minsyms;              /* Number of minimal symbols read */
 147     int n_psyms;                /* Number of partial symbols read */
 148     int n_syms;                 /* Number of full symbols read */
 149     int n_stabs;                /* Number of ".stabs" read (if applicable) */
 150     int n_types;                /* Number of types */
 151     int sz_strtab;              /* Size of stringtable, (if applicable) */
 152   };
 153
 154 #define OBJSTAT(objfile, expr) (objfile -> stats.expr)
 155 #define OBJSTATS struct objstats stats
 156 extern void print_objfile_statistics (void);
 157 extern void print_symbol_bcache_statistics (void);
 158
 159 /* Number of entries in the minimal symbol hash table.  */
 160 #define MINIMAL_SYMBOL_HASH_SIZE 2039
 161
 162 /* Master structure for keeping track of each file from which
 163    gdb reads symbols.  There are several ways these get allocated: 1.
 164    The main symbol file, symfile_objfile, set by the symbol-file command,
 165    2.  Additional symbol files added by the add-symbol-file command,
 166    3.  Shared library objfiles, added by ADD_SOLIB,  4.  symbol files
 167    for modules that were loaded when GDB attached to a remote system
 168    (see remote-vx.c).  */
 169
 170 struct objfile
 171   {
 172
 173     /* All struct objfile's are chained together by their next pointers.
 174        The program space field "objfiles"  (frequently referenced via
 175        the macro "object_files") points to the first link in this
 176        chain.  */
 177
 178     struct objfile *next;
 179
 180     /* The object file's name, tilde-expanded and absolute.  Malloc'd; free it
 181        if you free this struct.  This pointer is never NULL.  */
 182
 183     char *name;
 184
 185     CORE_ADDR addr_low;
 186
 187     /* Some flag bits for this objfile.
 188        The values are defined by OBJF_*.  */
 189
 190     unsigned short flags;
 191
 192     /* The program space associated with this objfile.  */
 193
 194     struct program_space *pspace;
 195
 196     /* Each objfile points to a linked list of symtabs derived from this file,
 197        one symtab structure for each compilation unit (source file).  Each link
 198        in the symtab list contains a backpointer to this objfile.  */
 199
 200     struct symtab *symtabs;
 201
 202     /* Each objfile points to a linked list of partial symtabs derived from
 203        this file, one partial symtab structure for each compilation unit
 204        (source file).  */
 205
 206     struct partial_symtab *psymtabs;
 207
 208     /* Map addresses to the entries of PSYMTABS.  It would be more efficient to
 209        have a map per the whole process but ADDRMAP cannot selectively remove
 210        its items during FREE_OBJFILE.  This mapping is already present even for
 211        PARTIAL_SYMTABs which still have no corresponding full SYMTABs read.  */
 212
 213     struct addrmap *psymtabs_addrmap;
 214
 215     /* List of freed partial symtabs, available for re-use.  */
 216
 217     struct partial_symtab *free_psymtabs;
 218
 219     /* The object file's BFD.  Can be null if the objfile contains only
 220        minimal symbols, e.g. the run time common symbols for SunOS4.  */
 221
 222     bfd *obfd;
 223
 224     /* The gdbarch associated with the BFD.  Note that this gdbarch is
 225        determined solely from BFD information, without looking at target
 226        information.  The gdbarch determined from a running target may
 227        differ from this e.g. with respect to register types and names.  */
 228
 229     struct gdbarch *gdbarch;
 230
 231     /* The modification timestamp of the object file, as of the last time
 232        we read its symbols.  */
 233
 234     long mtime;
 235
 236     /* Cached 32-bit CRC as computed by gnu_debuglink_crc32.  CRC32 is valid
 237        iff CRC32_P.  */
 238     unsigned long crc32;
 239     int crc32_p;
 240
 241     /* Obstack to hold objects that should be freed when we load a new symbol
 242        table from this object file.  */
 243
 244     struct obstack objfile_obstack;
 245
 246     /* A byte cache where we can stash arbitrary "chunks" of bytes that
 247        will not change.  */
 248
 249     struct psymbol_bcache *psymbol_cache; /* Byte cache for partial syms.  */
 250     struct bcache *macro_cache;           /* Byte cache for macros.  */
 251     struct bcache *filename_cache;        /* Byte cache for file names.  */
 252
 253     /* Hash table for mapping symbol names to demangled names.  Each
 254        entry in the hash table is actually two consecutive strings,
 255        both null-terminated; the first one is a mangled or linkage
 256        name, and the second is the demangled name or just a zero byte
 257        if the name doesn't demangle.  */
 258     struct htab *demangled_names_hash;
 259
 260     /* Vectors of all partial symbols read in from file.  The actual data
 261        is stored in the objfile_obstack.  */
 262
 263     struct psymbol_allocation_list global_psymbols;
 264     struct psymbol_allocation_list static_psymbols;
 265
 266     /* Each file contains a pointer to an array of minimal symbols for all
 267        global symbols that are defined within the file.  The array is
 268        terminated by a "null symbol", one that has a NULL pointer for the
 269        name and a zero value for the address.  This makes it easy to walk
 270        through the array when passed a pointer to somewhere in the middle
 271        of it.  There is also a count of the number of symbols, which does
 272        not include the terminating null symbol.  The array itself, as well
 273        as all the data that it points to, should be allocated on the
 274        objfile_obstack for this file.  */
 275
 276     struct minimal_symbol *msymbols;
 277     int minimal_symbol_count;
 278
 279     /* This is a hash table used to index the minimal symbols by name.  */
 280
 281     struct minimal_symbol *msymbol_hash[MINIMAL_SYMBOL_HASH_SIZE];
 282
 283     /* This hash table is used to index the minimal symbols by their
 284        demangled names.  */
 285
 286     struct minimal_symbol *msymbol_demangled_hash[MINIMAL_SYMBOL_HASH_SIZE];
 287
 288     /* Structure which keeps track of functions that manipulate objfile's
 289        of the same type as this objfile.  I.e. the function to read partial
 290        symbols for example.  Note that this structure is in statically
 291        allocated memory, and is shared by all objfiles that use the
 292        object module reader of this type.  */
 293
 294     const struct sym_fns *sf;
 295
 296     /* The per-objfile information about the entry point, the scope (file/func)
 297        containing the entry point, and the scope of the user's main() func.  */
 298
 299     struct entry_info ei;
 300
 301     /* Information about stabs.  Will be filled in with a dbx_symfile_info
 302        struct by those readers that need it.  */
 303     /* NOTE: cagney/2004-10-23: This has been replaced by per-objfile
 304        data points implemented using "data" and "num_data" below.  For
 305        an example of how to use this replacement, see "objfile_data"
 306        in "mips-tdep.c".  */
 307
 308     struct dbx_symfile_info *deprecated_sym_stab_info;
 309
 310     /* Hook for information for use by the symbol reader (currently used
 311        for information shared by sym_init and sym_read).  It is
 312        typically a pointer to malloc'd memory.  The symbol reader's finish
 313        function is responsible for freeing the memory thusly allocated.  */
 314     /* NOTE: cagney/2004-10-23: This has been replaced by per-objfile
 315        data points implemented using "data" and "num_data" below.  For
 316        an example of how to use this replacement, see "objfile_data"
 317        in "mips-tdep.c".  */
 318
 319     void *deprecated_sym_private;
 320
 321     /* Per objfile data-pointers required by other GDB modules.  */
 322     /* FIXME: kettenis/20030711: This mechanism could replace
 323        deprecated_sym_stab_info and deprecated_sym_private
 324        entirely.  */
 325
 326     void **data;
 327     unsigned num_data;
 328
 329     /* Set of relocation offsets to apply to each section.
 330        The table is indexed by the_bfd_section->index, thus it is generally
 331        as large as the number of sections in the binary.
 332        The table is stored on the objfile_obstack.
 333
 334        These offsets indicate that all symbols (including partial and
 335        minimal symbols) which have been read have been relocated by this
 336        much.  Symbols which are yet to be read need to be relocated by it.  */
 337
 338     struct section_offsets *section_offsets;
 339     int num_sections;
 340
 341     /* Indexes in the section_offsets array.  These are initialized by the
 342        *_symfile_offsets() family of functions (som_symfile_offsets,
 343        xcoff_symfile_offsets, default_symfile_offsets).  In theory they
 344        should correspond to the section indexes used by bfd for the
 345        current objfile.  The exception to this for the time being is the
 346        SOM version.  */
 347
 348     int sect_index_text;
 349     int sect_index_data;
 350     int sect_index_bss;
 351     int sect_index_rodata;
 352
 353     /* These pointers are used to locate the section table, which
 354        among other things, is used to map pc addresses into sections.
 355        SECTIONS points to the first entry in the table, and
 356        SECTIONS_END points to the first location past the last entry
 357        in the table.  The table is stored on the objfile_obstack.
 358        There is no particular order to the sections in this table, and it
 359        only contains sections we care about (e.g. non-empty, SEC_ALLOC).  */
 360
 361     struct obj_section *sections, *sections_end;
 362
 363     /* GDB allows to have debug symbols in separate object files.  This is
 364        used by .gnu_debuglink, ELF build id note and Mach-O OSO.
 365        Although this is a tree structure, GDB only support one level
 366        (ie a separate debug for a separate debug is not supported).  Note that
 367        separate debug object are in the main chain and therefore will be
 368        visited by ALL_OBJFILES & co iterators.  Separate debug objfile always
 369        has a non-nul separate_debug_objfile_backlink.  */
 370
 371     /* Link to the first separate debug object, if any.  */
 372     struct objfile *separate_debug_objfile;
 373
 374     /* If this is a separate debug object, this is used as a link to the
 375        actual executable objfile.  */
 376     struct objfile *separate_debug_objfile_backlink;
 377
 378     /* If this is a separate debug object, this is a link to the next one
 379        for the same executable objfile.  */
 380     struct objfile *separate_debug_objfile_link;
 381
 382     /* Place to stash various statistics about this objfile.  */
 383     OBJSTATS;
 384
 385     /* A linked list of symbols created when reading template types or
 386        function templates.  These symbols are not stored in any symbol
 387        table, so we have to keep them here to relocate them
 388        properly.  */
 389     struct symbol *template_symbols;
 390   };
 391
 392 /* Defines for the objfile flag word.  */
 393
 394 /* When an object file has its functions reordered (currently Irix-5.2
 395    shared libraries exhibit this behaviour), we will need an expensive
 396    algorithm to locate a partial symtab or symtab via an address.
 397    To avoid this penalty for normal object files, we use this flag,
 398    whose setting is determined upon symbol table read in.  */
 399
 400 #define OBJF_REORDERED  (1 << 0)        /* Functions are reordered */
 401
 402 /* Distinguish between an objfile for a shared library and a "vanilla"
 403    objfile.  (If not set, the objfile may still actually be a solib.
 404    This can happen if the user created the objfile by using the
 405    add-symbol-file command.  GDB doesn't in that situation actually
 406    check whether the file is a solib.  Rather, the target's
 407    implementation of the solib interface is responsible for setting
 408    this flag when noticing solibs used by an inferior.)  */
 409
 410 #define OBJF_SHARED     (1 << 1)        /* From a shared library */
 411
 412 /* User requested that this objfile be read in it's entirety.  */
 413
 414 #define OBJF_READNOW    (1 << 2)        /* Immediate full read */
 415
 416 /* This objfile was created because the user explicitly caused it
 417    (e.g., used the add-symbol-file command).  This bit offers a way
 418    for run_command to remove old objfile entries which are no longer
 419    valid (i.e., are associated with an old inferior), but to preserve
 420    ones that the user explicitly loaded via the add-symbol-file
 421    command.  */
 422
 423 #define OBJF_USERLOADED (1 << 3)        /* User loaded */
 424
 425 /* Set if we have tried to read partial symtabs for this objfile.
 426    This is used to allow lazy reading of partial symtabs.  */
 427
 428 #define OBJF_PSYMTABS_READ (1 << 4)
 429
 430 /* Set if this is the main symbol file
 431    (as opposed to symbol file for dynamically loaded code).  */
 432
 433 #define OBJF_MAINLINE (1 << 5)
 434
 435 /* The object file that contains the runtime common minimal symbols
 436    for SunOS4.  Note that this objfile has no associated BFD.  */
 437
 438 extern struct objfile *rt_common_objfile;
 439
 440 /* Declarations for functions defined in objfiles.c */
 441
 442 extern struct objfile *allocate_objfile (bfd *, int);
 443
 444 extern struct gdbarch *get_objfile_arch (struct objfile *);
 445
 446 extern void init_entry_point_info (struct objfile *);
 447
 448 extern int entry_point_address_query (CORE_ADDR *entry_p);
 449
 450 extern CORE_ADDR entry_point_address (void);
 451
 452 extern void build_objfile_section_table (struct objfile *);
 453
 454 extern void terminate_minimal_symbol_table (struct objfile *objfile);
 455
 456 extern struct objfile *objfile_separate_debug_iterate (const struct objfile *,
 457                                                        const struct objfile *);
 458
 459 extern void put_objfile_before (struct objfile *, struct objfile *);
 460
 461 extern void objfile_to_front (struct objfile *);
 462
 463 extern void add_separate_debug_objfile (struct objfile *, struct objfile *);
 464
 465 extern void unlink_objfile (struct objfile *);
 466
 467 extern void free_objfile (struct objfile *);
 468
 469 extern void free_objfile_separate_debug (struct objfile *);
 470
 471 extern struct cleanup *make_cleanup_free_objfile (struct objfile *);
 472
 473 extern void free_all_objfiles (void);
 474
 475 extern void objfile_relocate (struct objfile *, struct section_offsets *);
 476
 477 extern int objfile_has_partial_symbols (struct objfile *objfile);
 478
 479 extern int objfile_has_full_symbols (struct objfile *objfile);
 480
 481 extern int objfile_has_symbols (struct objfile *objfile);
 482
 483 extern int have_partial_symbols (void);
 484
 485 extern int have_full_symbols (void);
 486
 487 extern void objfiles_changed (void);
 488
 489 /* This operation deletes all objfile entries that represent solibs that
 490    weren't explicitly loaded by the user, via e.g., the add-symbol-file
 491    command.  */
 492
 493 extern void objfile_purge_solibs (void);
 494
 495 /* Functions for dealing with the minimal symbol table, really a misc
 496    address<->symbol mapping for things we don't have debug symbols for.  */
 497
 498 extern int have_minimal_symbols (void);
 499
 500 extern struct obj_section *find_pc_section (CORE_ADDR pc);
 501
 502 extern int in_plt_section (CORE_ADDR, char *);
 503
 504 /* Keep a registry of per-objfile data-pointers required by other GDB
 505    modules.  */
 506
 507 /* Allocate an entry in the per-objfile registry.  */
 508 extern const struct objfile_data *register_objfile_data (void);
 509
 510 /* Allocate an entry in the per-objfile registry.
 511    SAVE and FREE are called when clearing objfile data.
 512    First all registered SAVE functions are called.
 513    Then all registered FREE functions are called.
 514    Either or both of SAVE, FREE may be NULL.  */
 515 extern const struct objfile_data *register_objfile_data_with_cleanup
 516   (void (*save) (struct objfile *, void *),
 517    void (*free) (struct objfile *, void *));
 518
 519 extern void clear_objfile_data (struct objfile *objfile);
 520 extern void set_objfile_data (struct objfile *objfile,
 521                               const struct objfile_data *data, void *value);
 522 extern void *objfile_data (struct objfile *objfile,
 523                            const struct objfile_data *data);
 524
 525 extern struct bfd *gdb_bfd_ref (struct bfd *abfd);
 526 extern void gdb_bfd_unref (struct bfd *abfd);
 527 extern int gdb_bfd_close_or_warn (struct bfd *abfd);
 528 \f
 529
 530 /* Traverse all object files in the current program space.
 531    ALL_OBJFILES_SAFE works even if you delete the objfile during the
 532    traversal.  */
 533
 534 /* Traverse all object files in program space SS.  */
 535
 536 #define ALL_PSPACE_OBJFILES(ss, obj)                                    \
 537   for ((obj) = ss->objfiles; (obj) != NULL; (obj) = (obj)->next)        \
 538
 539 #define ALL_PSPACE_OBJFILES_SAFE(ss, obj, nxt)          \
 540   for ((obj) = ss->objfiles;                    \
 541        (obj) != NULL? ((nxt)=(obj)->next,1) :0; \
 542        (obj) = (nxt))
 543
 544 #define ALL_OBJFILES(obj)                           \
 545   for ((obj) = current_program_space->objfiles; \
 546        (obj) != NULL;                               \
 547        (obj) = (obj)->next)
 548
 549 #define ALL_OBJFILES_SAFE(obj,nxt)                      \
 550   for ((obj) = current_program_space->objfiles; \
 551        (obj) != NULL? ((nxt)=(obj)->next,1) :0; \
 552        (obj) = (nxt))
 553
 554 /* Traverse all symtabs in one objfile.  */
 555
 556 #define ALL_OBJFILE_SYMTABS(objfile, s) \
 557     for ((s) = (objfile) -> symtabs; (s) != NULL; (s) = (s) -> next)
 558
 559 /* Traverse all minimal symbols in one objfile.  */
 560
 561 #define ALL_OBJFILE_MSYMBOLS(objfile, m) \
 562     for ((m) = (objfile) -> msymbols; SYMBOL_LINKAGE_NAME(m) != NULL; (m)++)
 563
 564 /* Traverse all symtabs in all objfiles in the current symbol
 565    space.  */
 566
 567 #define ALL_SYMTABS(objfile, s) \
 568   ALL_OBJFILES (objfile)         \
 569     ALL_OBJFILE_SYMTABS (objfile, s)
 570
 571 #define ALL_PSPACE_SYMTABS(ss, objfile, s)              \
 572   ALL_PSPACE_OBJFILES (ss, objfile)                     \
 573     ALL_OBJFILE_SYMTABS (objfile, s)
 574
 575 /* Traverse all symtabs in all objfiles in the current program space,
 576    skipping included files (which share a blockvector with their
 577    primary symtab).  */
 578
 579 #define ALL_PRIMARY_SYMTABS(objfile, s) \
 580   ALL_OBJFILES (objfile)                \
 581     ALL_OBJFILE_SYMTABS (objfile, s)    \
 582       if ((s)->primary)
 583
 584 #define ALL_PSPACE_PRIMARY_SYMTABS(pspace, objfile, s)  \
 585   ALL_PSPACE_OBJFILES (ss, objfile)                     \
 586     ALL_OBJFILE_SYMTABS (objfile, s)                    \
 587       if ((s)->primary)
 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
 599 /* Traverse all obj_sections in all objfiles in the current program
 600    space.
 601
 602    Note that this detects a "break" in the inner loop, and exits
 603    immediately from the outer loop as well, thus, client code doesn't
 604    need to know that this is implemented with a double for.  The extra
 605    hair is to make sure that a "break;" stops the outer loop iterating
 606    as well, and both OBJFILE and OSECT are left unmodified:
 607
 608     - The outer loop learns about the inner loop's end condition, and
 609       stops iterating if it detects the inner loop didn't reach its
 610       end.  In other words, the outer loop keeps going only if the
 611       inner loop reached its end cleanly [(osect) ==
 612       (objfile)->sections_end].
 613
 614     - OSECT is initialized in the outer loop initialization
 615       expressions, such as if the inner loop has reached its end, so
 616       the check mentioned above succeeds the first time.
 617
 618     - The trick to not clearing OBJFILE on a "break;" is, in the outer
 619       loop's loop expression, advance OBJFILE, but iff the inner loop
 620       reached its end.  If not, there was a "break;", so leave OBJFILE
 621       as is; the outer loop's conditional will break immediately as
 622       well (as OSECT will be different from OBJFILE->sections_end).  */
 623
 624 #define ALL_OBJSECTIONS(objfile, osect)                                 \
 625   for ((objfile) = current_program_space->objfiles,                     \
 626          (objfile) != NULL ? ((osect) = (objfile)->sections_end) : 0;   \
 627        (objfile) != NULL                                                \
 628          && (osect) == (objfile)->sections_end;                         \
 629        ((osect) == (objfile)->sections_end                              \
 630         ? ((objfile) = (objfile)->next,                                 \
 631            (objfile) != NULL ? (osect) = (objfile)->sections_end : 0)   \
 632         : 0))                                                           \
 633     for ((osect) = (objfile)->sections;                                 \
 634          (osect) < (objfile)->sections_end;                             \
 635          (osect)++)
 636
 637 #define SECT_OFF_DATA(objfile) \
 638      ((objfile->sect_index_data == -1) \
 639       ? (internal_error (__FILE__, __LINE__, \
 640                          _("sect_index_data not initialized")), -1)     \
 641       : objfile->sect_index_data)
 642
 643 #define SECT_OFF_RODATA(objfile) \
 644      ((objfile->sect_index_rodata == -1) \
 645       ? (internal_error (__FILE__, __LINE__, \
 646                          _("sect_index_rodata not initialized")), -1)   \
 647       : objfile->sect_index_rodata)
 648
 649 #define SECT_OFF_TEXT(objfile) \
 650      ((objfile->sect_index_text == -1) \
 651       ? (internal_error (__FILE__, __LINE__, \
 652                          _("sect_index_text not initialized")), -1)     \
 653       : objfile->sect_index_text)
 654
 655 /* Sometimes the .bss section is missing from the objfile, so we don't
 656    want to die here.  Let the users of SECT_OFF_BSS deal with an
 657    uninitialized section index.  */
 658 #define SECT_OFF_BSS(objfile) (objfile)->sect_index_bss
 659
 660 /* Answer whether there is more than one object file loaded.  */
 661
 662 #define MULTI_OBJFILE_P() (object_files && object_files->next)
 663
 664 #endif /* !defined (OBJFILES_H) */