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