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c906108c SS |
1 | /* GDB routines for manipulating the minimal symbol tables. |
2 | Copyright 1992, 93, 94, 96, 97, 1998 Free Software Foundation, Inc. | |
3 | Contributed by Cygnus Support, using pieces from other GDB modules. | |
4 | ||
c5aa993b | 5 | This file is part of GDB. |
c906108c | 6 | |
c5aa993b JM |
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 2 of the License, or | |
10 | (at your option) any later version. | |
c906108c | 11 | |
c5aa993b JM |
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. | |
c906108c | 16 | |
c5aa993b JM |
17 | You should have received a copy of the GNU General Public License |
18 | along with this program; if not, write to the Free Software | |
19 | Foundation, Inc., 59 Temple Place - Suite 330, | |
20 | Boston, MA 02111-1307, USA. */ | |
c906108c SS |
21 | |
22 | ||
23 | /* This file contains support routines for creating, manipulating, and | |
24 | destroying minimal symbol tables. | |
25 | ||
26 | Minimal symbol tables are used to hold some very basic information about | |
27 | all defined global symbols (text, data, bss, abs, etc). The only two | |
28 | required pieces of information are the symbol's name and the address | |
29 | associated with that symbol. | |
30 | ||
31 | In many cases, even if a file was compiled with no special options for | |
32 | debugging at all, as long as was not stripped it will contain sufficient | |
33 | information to build useful minimal symbol tables using this structure. | |
c5aa993b | 34 | |
c906108c SS |
35 | Even when a file contains enough debugging information to build a full |
36 | symbol table, these minimal symbols are still useful for quickly mapping | |
37 | between names and addresses, and vice versa. They are also sometimes used | |
38 | to figure out what full symbol table entries need to be read in. */ | |
39 | ||
40 | ||
41 | #include "defs.h" | |
42 | #include "gdb_string.h" | |
43 | #include "symtab.h" | |
44 | #include "bfd.h" | |
45 | #include "symfile.h" | |
46 | #include "objfiles.h" | |
47 | #include "demangle.h" | |
48 | #include "gdb-stabs.h" | |
49 | ||
50 | /* Accumulate the minimal symbols for each objfile in bunches of BUNCH_SIZE. | |
51 | At the end, copy them all into one newly allocated location on an objfile's | |
52 | symbol obstack. */ | |
53 | ||
54 | #define BUNCH_SIZE 127 | |
55 | ||
56 | struct msym_bunch | |
c5aa993b JM |
57 | { |
58 | struct msym_bunch *next; | |
59 | struct minimal_symbol contents[BUNCH_SIZE]; | |
60 | }; | |
c906108c SS |
61 | |
62 | /* Bunch currently being filled up. | |
63 | The next field points to chain of filled bunches. */ | |
64 | ||
65 | static struct msym_bunch *msym_bunch; | |
66 | ||
67 | /* Number of slots filled in current bunch. */ | |
68 | ||
69 | static int msym_bunch_index; | |
70 | ||
71 | /* Total number of minimal symbols recorded so far for the objfile. */ | |
72 | ||
73 | static int msym_count; | |
74 | ||
75 | /* Prototypes for local functions. */ | |
76 | ||
77 | static int | |
78 | compare_minimal_symbols PARAMS ((const void *, const void *)); | |
79 | ||
80 | static int | |
81 | compact_minimal_symbols PARAMS ((struct minimal_symbol *, int)); | |
82 | ||
83 | /* Look through all the current minimal symbol tables and find the | |
84 | first minimal symbol that matches NAME. If OBJF is non-NULL, limit | |
85 | the search to that objfile. If SFILE is non-NULL, limit the search | |
86 | to that source file. Returns a pointer to the minimal symbol that | |
87 | matches, or NULL if no match is found. | |
88 | ||
89 | Note: One instance where there may be duplicate minimal symbols with | |
90 | the same name is when the symbol tables for a shared library and the | |
91 | symbol tables for an executable contain global symbols with the same | |
92 | names (the dynamic linker deals with the duplication). */ | |
93 | ||
94 | struct minimal_symbol * | |
95 | lookup_minimal_symbol (name, sfile, objf) | |
96 | register const char *name; | |
97 | const char *sfile; | |
98 | struct objfile *objf; | |
99 | { | |
100 | struct objfile *objfile; | |
101 | struct minimal_symbol *msymbol; | |
102 | struct minimal_symbol *found_symbol = NULL; | |
103 | struct minimal_symbol *found_file_symbol = NULL; | |
104 | struct minimal_symbol *trampoline_symbol = NULL; | |
105 | ||
106 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
107 | if (sfile != NULL) | |
108 | { | |
109 | char *p = strrchr (sfile, '/'); | |
110 | if (p != NULL) | |
111 | sfile = p + 1; | |
112 | } | |
113 | #endif | |
114 | ||
115 | for (objfile = object_files; | |
116 | objfile != NULL && found_symbol == NULL; | |
c5aa993b | 117 | objfile = objfile->next) |
c906108c SS |
118 | { |
119 | if (objf == NULL || objf == objfile) | |
120 | { | |
c5aa993b | 121 | for (msymbol = objfile->msymbols; |
c906108c SS |
122 | msymbol != NULL && SYMBOL_NAME (msymbol) != NULL && |
123 | found_symbol == NULL; | |
124 | msymbol++) | |
125 | { | |
126 | if (SYMBOL_MATCHES_NAME (msymbol, name)) | |
127 | { | |
128 | switch (MSYMBOL_TYPE (msymbol)) | |
129 | { | |
130 | case mst_file_text: | |
131 | case mst_file_data: | |
132 | case mst_file_bss: | |
133 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
134 | if (sfile == NULL || STREQ (msymbol->filename, sfile)) | |
135 | found_file_symbol = msymbol; | |
136 | #else | |
137 | /* We have neither the ability nor the need to | |
c5aa993b JM |
138 | deal with the SFILE parameter. If we find |
139 | more than one symbol, just return the latest | |
140 | one (the user can't expect useful behavior in | |
141 | that case). */ | |
c906108c SS |
142 | found_file_symbol = msymbol; |
143 | #endif | |
144 | break; | |
145 | ||
c5aa993b | 146 | case mst_solib_trampoline: |
c906108c SS |
147 | |
148 | /* If a trampoline symbol is found, we prefer to | |
c5aa993b JM |
149 | keep looking for the *real* symbol. If the |
150 | actual symbol is not found, then we'll use the | |
151 | trampoline entry. */ | |
c906108c SS |
152 | if (trampoline_symbol == NULL) |
153 | trampoline_symbol = msymbol; | |
154 | break; | |
155 | ||
156 | case mst_unknown: | |
157 | default: | |
158 | found_symbol = msymbol; | |
159 | break; | |
160 | } | |
161 | } | |
162 | } | |
163 | } | |
164 | } | |
165 | /* External symbols are best. */ | |
166 | if (found_symbol) | |
167 | return found_symbol; | |
168 | ||
169 | /* File-local symbols are next best. */ | |
170 | if (found_file_symbol) | |
171 | return found_file_symbol; | |
172 | ||
173 | /* Symbols for shared library trampolines are next best. */ | |
174 | if (trampoline_symbol) | |
175 | return trampoline_symbol; | |
176 | ||
177 | return NULL; | |
178 | } | |
179 | ||
180 | /* Look through all the current minimal symbol tables and find the | |
181 | first minimal symbol that matches NAME and of text type. | |
182 | If OBJF is non-NULL, limit | |
183 | the search to that objfile. If SFILE is non-NULL, limit the search | |
184 | to that source file. Returns a pointer to the minimal symbol that | |
185 | matches, or NULL if no match is found. | |
c5aa993b JM |
186 | */ |
187 | ||
c906108c SS |
188 | struct minimal_symbol * |
189 | lookup_minimal_symbol_text (name, sfile, objf) | |
190 | register const char *name; | |
191 | const char *sfile; | |
192 | struct objfile *objf; | |
193 | { | |
194 | struct objfile *objfile; | |
195 | struct minimal_symbol *msymbol; | |
196 | struct minimal_symbol *found_symbol = NULL; | |
197 | struct minimal_symbol *found_file_symbol = NULL; | |
198 | ||
199 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
200 | if (sfile != NULL) | |
201 | { | |
202 | char *p = strrchr (sfile, '/'); | |
203 | if (p != NULL) | |
204 | sfile = p + 1; | |
205 | } | |
206 | #endif | |
207 | ||
208 | for (objfile = object_files; | |
209 | objfile != NULL && found_symbol == NULL; | |
c5aa993b | 210 | objfile = objfile->next) |
c906108c SS |
211 | { |
212 | if (objf == NULL || objf == objfile) | |
213 | { | |
c5aa993b | 214 | for (msymbol = objfile->msymbols; |
c906108c SS |
215 | msymbol != NULL && SYMBOL_NAME (msymbol) != NULL && |
216 | found_symbol == NULL; | |
217 | msymbol++) | |
218 | { | |
c5aa993b | 219 | if (SYMBOL_MATCHES_NAME (msymbol, name) && |
c906108c SS |
220 | (MSYMBOL_TYPE (msymbol) == mst_text || |
221 | MSYMBOL_TYPE (msymbol) == mst_file_text)) | |
222 | { | |
223 | switch (MSYMBOL_TYPE (msymbol)) | |
224 | { | |
225 | case mst_file_text: | |
226 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
227 | if (sfile == NULL || STREQ (msymbol->filename, sfile)) | |
228 | found_file_symbol = msymbol; | |
229 | #else | |
230 | /* We have neither the ability nor the need to | |
c5aa993b JM |
231 | deal with the SFILE parameter. If we find |
232 | more than one symbol, just return the latest | |
233 | one (the user can't expect useful behavior in | |
234 | that case). */ | |
c906108c SS |
235 | found_file_symbol = msymbol; |
236 | #endif | |
237 | break; | |
238 | default: | |
239 | found_symbol = msymbol; | |
240 | break; | |
241 | } | |
242 | } | |
243 | } | |
244 | } | |
245 | } | |
246 | /* External symbols are best. */ | |
247 | if (found_symbol) | |
248 | return found_symbol; | |
249 | ||
250 | /* File-local symbols are next best. */ | |
251 | if (found_file_symbol) | |
252 | return found_file_symbol; | |
253 | ||
254 | return NULL; | |
255 | } | |
256 | ||
257 | /* Look through all the current minimal symbol tables and find the | |
258 | first minimal symbol that matches NAME and of solib trampoline type. | |
259 | If OBJF is non-NULL, limit | |
260 | the search to that objfile. If SFILE is non-NULL, limit the search | |
261 | to that source file. Returns a pointer to the minimal symbol that | |
262 | matches, or NULL if no match is found. | |
c5aa993b JM |
263 | */ |
264 | ||
c906108c SS |
265 | struct minimal_symbol * |
266 | lookup_minimal_symbol_solib_trampoline (name, sfile, objf) | |
267 | register const char *name; | |
268 | const char *sfile; | |
269 | struct objfile *objf; | |
270 | { | |
271 | struct objfile *objfile; | |
272 | struct minimal_symbol *msymbol; | |
273 | struct minimal_symbol *found_symbol = NULL; | |
274 | ||
275 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
276 | if (sfile != NULL) | |
277 | { | |
278 | char *p = strrchr (sfile, '/'); | |
279 | if (p != NULL) | |
280 | sfile = p + 1; | |
281 | } | |
282 | #endif | |
283 | ||
284 | for (objfile = object_files; | |
285 | objfile != NULL && found_symbol == NULL; | |
c5aa993b | 286 | objfile = objfile->next) |
c906108c SS |
287 | { |
288 | if (objf == NULL || objf == objfile) | |
289 | { | |
c5aa993b | 290 | for (msymbol = objfile->msymbols; |
c906108c SS |
291 | msymbol != NULL && SYMBOL_NAME (msymbol) != NULL && |
292 | found_symbol == NULL; | |
293 | msymbol++) | |
294 | { | |
c5aa993b | 295 | if (SYMBOL_MATCHES_NAME (msymbol, name) && |
c906108c SS |
296 | MSYMBOL_TYPE (msymbol) == mst_solib_trampoline) |
297 | return msymbol; | |
298 | } | |
299 | } | |
300 | } | |
301 | ||
302 | return NULL; | |
303 | } | |
304 | ||
305 | ||
306 | /* Search through the minimal symbol table for each objfile and find | |
307 | the symbol whose address is the largest address that is still less | |
308 | than or equal to PC, and matches SECTION (if non-null). Returns a | |
309 | pointer to the minimal symbol if such a symbol is found, or NULL if | |
310 | PC is not in a suitable range. Note that we need to look through | |
311 | ALL the minimal symbol tables before deciding on the symbol that | |
312 | comes closest to the specified PC. This is because objfiles can | |
313 | overlap, for example objfile A has .text at 0x100 and .data at | |
314 | 0x40000 and objfile B has .text at 0x234 and .data at 0x40048. */ | |
315 | ||
316 | struct minimal_symbol * | |
317 | lookup_minimal_symbol_by_pc_section (pc, section) | |
318 | CORE_ADDR pc; | |
319 | asection *section; | |
320 | { | |
321 | int lo; | |
322 | int hi; | |
323 | int new; | |
324 | struct objfile *objfile; | |
325 | struct minimal_symbol *msymbol; | |
326 | struct minimal_symbol *best_symbol = NULL; | |
327 | ||
328 | /* pc has to be in a known section. This ensures that anything beyond | |
329 | the end of the last segment doesn't appear to be part of the last | |
330 | function in the last segment. */ | |
331 | if (find_pc_section (pc) == NULL) | |
332 | return NULL; | |
333 | ||
334 | for (objfile = object_files; | |
335 | objfile != NULL; | |
c5aa993b | 336 | objfile = objfile->next) |
c906108c SS |
337 | { |
338 | /* If this objfile has a minimal symbol table, go search it using | |
c5aa993b JM |
339 | a binary search. Note that a minimal symbol table always consists |
340 | of at least two symbols, a "real" symbol and the terminating | |
341 | "null symbol". If there are no real symbols, then there is no | |
342 | minimal symbol table at all. */ | |
c906108c | 343 | |
c5aa993b | 344 | if ((msymbol = objfile->msymbols) != NULL) |
c906108c SS |
345 | { |
346 | lo = 0; | |
c5aa993b | 347 | hi = objfile->minimal_symbol_count - 1; |
c906108c SS |
348 | |
349 | /* This code assumes that the minimal symbols are sorted by | |
350 | ascending address values. If the pc value is greater than or | |
351 | equal to the first symbol's address, then some symbol in this | |
352 | minimal symbol table is a suitable candidate for being the | |
353 | "best" symbol. This includes the last real symbol, for cases | |
354 | where the pc value is larger than any address in this vector. | |
355 | ||
356 | By iterating until the address associated with the current | |
357 | hi index (the endpoint of the test interval) is less than | |
358 | or equal to the desired pc value, we accomplish two things: | |
359 | (1) the case where the pc value is larger than any minimal | |
360 | symbol address is trivially solved, (2) the address associated | |
361 | with the hi index is always the one we want when the interation | |
362 | terminates. In essence, we are iterating the test interval | |
363 | down until the pc value is pushed out of it from the high end. | |
364 | ||
365 | Warning: this code is trickier than it would appear at first. */ | |
366 | ||
367 | /* Should also require that pc is <= end of objfile. FIXME! */ | |
368 | if (pc >= SYMBOL_VALUE_ADDRESS (&msymbol[lo])) | |
369 | { | |
370 | while (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) > pc) | |
371 | { | |
372 | /* pc is still strictly less than highest address */ | |
373 | /* Note "new" will always be >= lo */ | |
374 | new = (lo + hi) / 2; | |
375 | if ((SYMBOL_VALUE_ADDRESS (&msymbol[new]) >= pc) || | |
376 | (lo == new)) | |
377 | { | |
378 | hi = new; | |
379 | } | |
380 | else | |
381 | { | |
382 | lo = new; | |
383 | } | |
384 | } | |
385 | ||
386 | /* If we have multiple symbols at the same address, we want | |
c5aa993b JM |
387 | hi to point to the last one. That way we can find the |
388 | right symbol if it has an index greater than hi. */ | |
389 | while (hi < objfile->minimal_symbol_count - 1 | |
c906108c | 390 | && (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) |
c5aa993b | 391 | == SYMBOL_VALUE_ADDRESS (&msymbol[hi + 1]))) |
c906108c SS |
392 | hi++; |
393 | ||
394 | /* The minimal symbol indexed by hi now is the best one in this | |
c5aa993b JM |
395 | objfile's minimal symbol table. See if it is the best one |
396 | overall. */ | |
c906108c SS |
397 | |
398 | /* Skip any absolute symbols. This is apparently what adb | |
c5aa993b JM |
399 | and dbx do, and is needed for the CM-5. There are two |
400 | known possible problems: (1) on ELF, apparently end, edata, | |
401 | etc. are absolute. Not sure ignoring them here is a big | |
402 | deal, but if we want to use them, the fix would go in | |
403 | elfread.c. (2) I think shared library entry points on the | |
404 | NeXT are absolute. If we want special handling for this | |
405 | it probably should be triggered by a special | |
406 | mst_abs_or_lib or some such. */ | |
c906108c SS |
407 | while (hi >= 0 |
408 | && msymbol[hi].type == mst_abs) | |
409 | --hi; | |
410 | ||
411 | /* If "section" specified, skip any symbol from wrong section */ | |
412 | /* This is the new code that distinguishes it from the old function */ | |
413 | if (section) | |
414 | while (hi >= 0 | |
415 | && SYMBOL_BFD_SECTION (&msymbol[hi]) != section) | |
416 | --hi; | |
417 | ||
418 | if (hi >= 0 | |
419 | && ((best_symbol == NULL) || | |
c5aa993b | 420 | (SYMBOL_VALUE_ADDRESS (best_symbol) < |
c906108c SS |
421 | SYMBOL_VALUE_ADDRESS (&msymbol[hi])))) |
422 | { | |
423 | best_symbol = &msymbol[hi]; | |
424 | } | |
425 | } | |
426 | } | |
427 | } | |
428 | return (best_symbol); | |
429 | } | |
430 | ||
431 | /* Backward compatibility: search through the minimal symbol table | |
432 | for a matching PC (no section given) */ | |
433 | ||
434 | struct minimal_symbol * | |
435 | lookup_minimal_symbol_by_pc (pc) | |
436 | CORE_ADDR pc; | |
437 | { | |
438 | return lookup_minimal_symbol_by_pc_section (pc, find_pc_mapped_section (pc)); | |
439 | } | |
440 | ||
441 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
442 | CORE_ADDR | |
443 | find_stab_function_addr (namestring, pst, objfile) | |
444 | char *namestring; | |
445 | struct partial_symtab *pst; | |
446 | struct objfile *objfile; | |
447 | { | |
448 | struct minimal_symbol *msym; | |
449 | char *p; | |
450 | int n; | |
451 | ||
452 | p = strchr (namestring, ':'); | |
453 | if (p == NULL) | |
454 | p = namestring; | |
455 | n = p - namestring; | |
456 | p = alloca (n + 2); | |
457 | strncpy (p, namestring, n); | |
458 | p[n] = 0; | |
459 | ||
460 | msym = lookup_minimal_symbol (p, pst->filename, objfile); | |
461 | if (msym == NULL) | |
462 | { | |
463 | /* Sun Fortran appends an underscore to the minimal symbol name, | |
c5aa993b JM |
464 | try again with an appended underscore if the minimal symbol |
465 | was not found. */ | |
c906108c SS |
466 | p[n] = '_'; |
467 | p[n + 1] = 0; | |
468 | msym = lookup_minimal_symbol (p, pst->filename, objfile); | |
469 | } | |
470 | return msym == NULL ? 0 : SYMBOL_VALUE_ADDRESS (msym); | |
471 | } | |
472 | #endif /* SOFUN_ADDRESS_MAYBE_MISSING */ | |
c906108c | 473 | \f |
c5aa993b | 474 | |
c906108c SS |
475 | /* Return leading symbol character for a BFD. If BFD is NULL, |
476 | return the leading symbol character from the main objfile. */ | |
477 | ||
478 | static int get_symbol_leading_char PARAMS ((bfd *)); | |
479 | ||
480 | static int | |
481 | get_symbol_leading_char (abfd) | |
c5aa993b | 482 | bfd *abfd; |
c906108c SS |
483 | { |
484 | if (abfd != NULL) | |
485 | return bfd_get_symbol_leading_char (abfd); | |
486 | if (symfile_objfile != NULL && symfile_objfile->obfd != NULL) | |
487 | return bfd_get_symbol_leading_char (symfile_objfile->obfd); | |
488 | return 0; | |
489 | } | |
490 | ||
491 | /* Prepare to start collecting minimal symbols. Note that presetting | |
492 | msym_bunch_index to BUNCH_SIZE causes the first call to save a minimal | |
493 | symbol to allocate the memory for the first bunch. */ | |
494 | ||
495 | void | |
496 | init_minimal_symbol_collection () | |
497 | { | |
498 | msym_count = 0; | |
499 | msym_bunch = NULL; | |
500 | msym_bunch_index = BUNCH_SIZE; | |
501 | } | |
502 | ||
503 | void | |
504 | prim_record_minimal_symbol (name, address, ms_type, objfile) | |
505 | const char *name; | |
506 | CORE_ADDR address; | |
507 | enum minimal_symbol_type ms_type; | |
508 | struct objfile *objfile; | |
509 | { | |
510 | int section; | |
511 | ||
512 | switch (ms_type) | |
513 | { | |
514 | case mst_text: | |
515 | case mst_file_text: | |
516 | case mst_solib_trampoline: | |
517 | section = SECT_OFF_TEXT; | |
518 | break; | |
519 | case mst_data: | |
520 | case mst_file_data: | |
521 | section = SECT_OFF_DATA; | |
522 | break; | |
523 | case mst_bss: | |
524 | case mst_file_bss: | |
525 | section = SECT_OFF_BSS; | |
526 | break; | |
527 | default: | |
528 | section = -1; | |
529 | } | |
530 | ||
531 | prim_record_minimal_symbol_and_info (name, address, ms_type, | |
532 | NULL, section, NULL, objfile); | |
533 | } | |
534 | ||
535 | /* Record a minimal symbol in the msym bunches. Returns the symbol | |
536 | newly created. */ | |
537 | ||
538 | struct minimal_symbol * | |
539 | prim_record_minimal_symbol_and_info (name, address, ms_type, info, section, | |
540 | bfd_section, objfile) | |
541 | const char *name; | |
542 | CORE_ADDR address; | |
543 | enum minimal_symbol_type ms_type; | |
544 | char *info; | |
545 | int section; | |
546 | asection *bfd_section; | |
547 | struct objfile *objfile; | |
548 | { | |
549 | register struct msym_bunch *new; | |
550 | register struct minimal_symbol *msymbol; | |
551 | ||
552 | if (ms_type == mst_file_text) | |
553 | { | |
554 | /* Don't put gcc_compiled, __gnu_compiled_cplus, and friends into | |
c5aa993b JM |
555 | the minimal symbols, because if there is also another symbol |
556 | at the same address (e.g. the first function of the file), | |
557 | lookup_minimal_symbol_by_pc would have no way of getting the | |
558 | right one. */ | |
c906108c SS |
559 | if (name[0] == 'g' |
560 | && (strcmp (name, GCC_COMPILED_FLAG_SYMBOL) == 0 | |
561 | || strcmp (name, GCC2_COMPILED_FLAG_SYMBOL) == 0)) | |
562 | return (NULL); | |
563 | ||
564 | { | |
565 | const char *tempstring = name; | |
566 | if (tempstring[0] == get_symbol_leading_char (objfile->obfd)) | |
567 | ++tempstring; | |
568 | if (STREQN (tempstring, "__gnu_compiled", 14)) | |
569 | return (NULL); | |
570 | } | |
571 | } | |
572 | ||
573 | if (msym_bunch_index == BUNCH_SIZE) | |
574 | { | |
575 | new = (struct msym_bunch *) xmalloc (sizeof (struct msym_bunch)); | |
576 | msym_bunch_index = 0; | |
c5aa993b | 577 | new->next = msym_bunch; |
c906108c SS |
578 | msym_bunch = new; |
579 | } | |
c5aa993b | 580 | msymbol = &msym_bunch->contents[msym_bunch_index]; |
c906108c SS |
581 | SYMBOL_NAME (msymbol) = obsavestring ((char *) name, strlen (name), |
582 | &objfile->symbol_obstack); | |
583 | SYMBOL_INIT_LANGUAGE_SPECIFIC (msymbol, language_unknown); | |
584 | SYMBOL_VALUE_ADDRESS (msymbol) = address; | |
585 | SYMBOL_SECTION (msymbol) = section; | |
586 | SYMBOL_BFD_SECTION (msymbol) = bfd_section; | |
587 | ||
588 | MSYMBOL_TYPE (msymbol) = ms_type; | |
589 | /* FIXME: This info, if it remains, needs its own field. */ | |
c5aa993b | 590 | MSYMBOL_INFO (msymbol) = info; /* FIXME! */ |
c906108c SS |
591 | msym_bunch_index++; |
592 | msym_count++; | |
593 | OBJSTAT (objfile, n_minsyms++); | |
594 | return msymbol; | |
595 | } | |
596 | ||
597 | /* Compare two minimal symbols by address and return a signed result based | |
598 | on unsigned comparisons, so that we sort into unsigned numeric order. | |
599 | Within groups with the same address, sort by name. */ | |
600 | ||
601 | static int | |
602 | compare_minimal_symbols (fn1p, fn2p) | |
603 | const PTR fn1p; | |
604 | const PTR fn2p; | |
605 | { | |
606 | register const struct minimal_symbol *fn1; | |
607 | register const struct minimal_symbol *fn2; | |
608 | ||
609 | fn1 = (const struct minimal_symbol *) fn1p; | |
610 | fn2 = (const struct minimal_symbol *) fn2p; | |
611 | ||
612 | if (SYMBOL_VALUE_ADDRESS (fn1) < SYMBOL_VALUE_ADDRESS (fn2)) | |
613 | { | |
c5aa993b | 614 | return (-1); /* addr 1 is less than addr 2 */ |
c906108c SS |
615 | } |
616 | else if (SYMBOL_VALUE_ADDRESS (fn1) > SYMBOL_VALUE_ADDRESS (fn2)) | |
617 | { | |
c5aa993b | 618 | return (1); /* addr 1 is greater than addr 2 */ |
c906108c | 619 | } |
c5aa993b JM |
620 | else |
621 | /* addrs are equal: sort by name */ | |
c906108c SS |
622 | { |
623 | char *name1 = SYMBOL_NAME (fn1); | |
624 | char *name2 = SYMBOL_NAME (fn2); | |
625 | ||
626 | if (name1 && name2) /* both have names */ | |
627 | return strcmp (name1, name2); | |
628 | else if (name2) | |
c5aa993b JM |
629 | return 1; /* fn1 has no name, so it is "less" */ |
630 | else if (name1) /* fn2 has no name, so it is "less" */ | |
c906108c SS |
631 | return -1; |
632 | else | |
c5aa993b | 633 | return (0); /* neither has a name, so they're equal. */ |
c906108c SS |
634 | } |
635 | } | |
636 | ||
637 | /* Discard the currently collected minimal symbols, if any. If we wish | |
638 | to save them for later use, we must have already copied them somewhere | |
639 | else before calling this function. | |
640 | ||
641 | FIXME: We could allocate the minimal symbol bunches on their own | |
642 | obstack and then simply blow the obstack away when we are done with | |
643 | it. Is it worth the extra trouble though? */ | |
644 | ||
645 | /* ARGSUSED */ | |
646 | void | |
647 | discard_minimal_symbols (foo) | |
648 | int foo; | |
649 | { | |
650 | register struct msym_bunch *next; | |
651 | ||
652 | while (msym_bunch != NULL) | |
653 | { | |
c5aa993b JM |
654 | next = msym_bunch->next; |
655 | free ((PTR) msym_bunch); | |
c906108c SS |
656 | msym_bunch = next; |
657 | } | |
658 | } | |
659 | ||
660 | /* Compact duplicate entries out of a minimal symbol table by walking | |
661 | through the table and compacting out entries with duplicate addresses | |
662 | and matching names. Return the number of entries remaining. | |
663 | ||
664 | On entry, the table resides between msymbol[0] and msymbol[mcount]. | |
665 | On exit, it resides between msymbol[0] and msymbol[result_count]. | |
666 | ||
667 | When files contain multiple sources of symbol information, it is | |
668 | possible for the minimal symbol table to contain many duplicate entries. | |
669 | As an example, SVR4 systems use ELF formatted object files, which | |
670 | usually contain at least two different types of symbol tables (a | |
671 | standard ELF one and a smaller dynamic linking table), as well as | |
672 | DWARF debugging information for files compiled with -g. | |
673 | ||
674 | Without compacting, the minimal symbol table for gdb itself contains | |
675 | over a 1000 duplicates, about a third of the total table size. Aside | |
676 | from the potential trap of not noticing that two successive entries | |
677 | identify the same location, this duplication impacts the time required | |
678 | to linearly scan the table, which is done in a number of places. So we | |
679 | just do one linear scan here and toss out the duplicates. | |
680 | ||
681 | Note that we are not concerned here about recovering the space that | |
682 | is potentially freed up, because the strings themselves are allocated | |
683 | on the symbol_obstack, and will get automatically freed when the symbol | |
684 | table is freed. The caller can free up the unused minimal symbols at | |
685 | the end of the compacted region if their allocation strategy allows it. | |
686 | ||
687 | Also note we only go up to the next to last entry within the loop | |
688 | and then copy the last entry explicitly after the loop terminates. | |
689 | ||
690 | Since the different sources of information for each symbol may | |
691 | have different levels of "completeness", we may have duplicates | |
692 | that have one entry with type "mst_unknown" and the other with a | |
693 | known type. So if the one we are leaving alone has type mst_unknown, | |
694 | overwrite its type with the type from the one we are compacting out. */ | |
695 | ||
696 | static int | |
697 | compact_minimal_symbols (msymbol, mcount) | |
698 | struct minimal_symbol *msymbol; | |
699 | int mcount; | |
700 | { | |
701 | struct minimal_symbol *copyfrom; | |
702 | struct minimal_symbol *copyto; | |
703 | ||
704 | if (mcount > 0) | |
705 | { | |
706 | copyfrom = copyto = msymbol; | |
707 | while (copyfrom < msymbol + mcount - 1) | |
708 | { | |
c5aa993b | 709 | if (SYMBOL_VALUE_ADDRESS (copyfrom) == |
c906108c SS |
710 | SYMBOL_VALUE_ADDRESS ((copyfrom + 1)) && |
711 | (STREQ (SYMBOL_NAME (copyfrom), SYMBOL_NAME ((copyfrom + 1))))) | |
712 | { | |
c5aa993b | 713 | if (MSYMBOL_TYPE ((copyfrom + 1)) == mst_unknown) |
c906108c SS |
714 | { |
715 | MSYMBOL_TYPE ((copyfrom + 1)) = MSYMBOL_TYPE (copyfrom); | |
716 | } | |
717 | copyfrom++; | |
718 | } | |
719 | else | |
720 | { | |
721 | *copyto++ = *copyfrom++; | |
722 | } | |
723 | } | |
724 | *copyto++ = *copyfrom++; | |
725 | mcount = copyto - msymbol; | |
726 | } | |
727 | return (mcount); | |
728 | } | |
729 | ||
730 | /* Add the minimal symbols in the existing bunches to the objfile's official | |
731 | minimal symbol table. In most cases there is no minimal symbol table yet | |
732 | for this objfile, and the existing bunches are used to create one. Once | |
733 | in a while (for shared libraries for example), we add symbols (e.g. common | |
734 | symbols) to an existing objfile. | |
735 | ||
736 | Because of the way minimal symbols are collected, we generally have no way | |
737 | of knowing what source language applies to any particular minimal symbol. | |
738 | Specifically, we have no way of knowing if the minimal symbol comes from a | |
739 | C++ compilation unit or not. So for the sake of supporting cached | |
740 | demangled C++ names, we have no choice but to try and demangle each new one | |
741 | that comes in. If the demangling succeeds, then we assume it is a C++ | |
742 | symbol and set the symbol's language and demangled name fields | |
743 | appropriately. Note that in order to avoid unnecessary demanglings, and | |
744 | allocating obstack space that subsequently can't be freed for the demangled | |
745 | names, we mark all newly added symbols with language_auto. After | |
746 | compaction of the minimal symbols, we go back and scan the entire minimal | |
747 | symbol table looking for these new symbols. For each new symbol we attempt | |
748 | to demangle it, and if successful, record it as a language_cplus symbol | |
749 | and cache the demangled form on the symbol obstack. Symbols which don't | |
750 | demangle are marked as language_unknown symbols, which inhibits future | |
751 | attempts to demangle them if we later add more minimal symbols. */ | |
752 | ||
753 | void | |
754 | install_minimal_symbols (objfile) | |
755 | struct objfile *objfile; | |
756 | { | |
757 | register int bindex; | |
758 | register int mcount; | |
759 | register struct msym_bunch *bunch; | |
760 | register struct minimal_symbol *msymbols; | |
761 | int alloc_count; | |
762 | register char leading_char; | |
763 | ||
764 | if (msym_count > 0) | |
765 | { | |
766 | /* Allocate enough space in the obstack, into which we will gather the | |
c5aa993b JM |
767 | bunches of new and existing minimal symbols, sort them, and then |
768 | compact out the duplicate entries. Once we have a final table, | |
769 | we will give back the excess space. */ | |
c906108c SS |
770 | |
771 | alloc_count = msym_count + objfile->minimal_symbol_count + 1; | |
772 | obstack_blank (&objfile->symbol_obstack, | |
773 | alloc_count * sizeof (struct minimal_symbol)); | |
774 | msymbols = (struct minimal_symbol *) | |
c5aa993b | 775 | obstack_base (&objfile->symbol_obstack); |
c906108c SS |
776 | |
777 | /* Copy in the existing minimal symbols, if there are any. */ | |
778 | ||
779 | if (objfile->minimal_symbol_count) | |
c5aa993b JM |
780 | memcpy ((char *) msymbols, (char *) objfile->msymbols, |
781 | objfile->minimal_symbol_count * sizeof (struct minimal_symbol)); | |
c906108c SS |
782 | |
783 | /* Walk through the list of minimal symbol bunches, adding each symbol | |
c5aa993b JM |
784 | to the new contiguous array of symbols. Note that we start with the |
785 | current, possibly partially filled bunch (thus we use the current | |
786 | msym_bunch_index for the first bunch we copy over), and thereafter | |
787 | each bunch is full. */ | |
788 | ||
c906108c SS |
789 | mcount = objfile->minimal_symbol_count; |
790 | leading_char = get_symbol_leading_char (objfile->obfd); | |
c5aa993b JM |
791 | |
792 | for (bunch = msym_bunch; bunch != NULL; bunch = bunch->next) | |
c906108c SS |
793 | { |
794 | for (bindex = 0; bindex < msym_bunch_index; bindex++, mcount++) | |
795 | { | |
c5aa993b | 796 | msymbols[mcount] = bunch->contents[bindex]; |
c906108c SS |
797 | SYMBOL_LANGUAGE (&msymbols[mcount]) = language_auto; |
798 | if (SYMBOL_NAME (&msymbols[mcount])[0] == leading_char) | |
799 | { | |
c5aa993b | 800 | SYMBOL_NAME (&msymbols[mcount])++; |
c906108c SS |
801 | } |
802 | } | |
803 | msym_bunch_index = BUNCH_SIZE; | |
804 | } | |
805 | ||
806 | /* Sort the minimal symbols by address. */ | |
c5aa993b | 807 | |
c906108c SS |
808 | qsort (msymbols, mcount, sizeof (struct minimal_symbol), |
809 | compare_minimal_symbols); | |
c5aa993b | 810 | |
c906108c | 811 | /* Compact out any duplicates, and free up whatever space we are |
c5aa993b JM |
812 | no longer using. */ |
813 | ||
c906108c SS |
814 | mcount = compact_minimal_symbols (msymbols, mcount); |
815 | ||
816 | obstack_blank (&objfile->symbol_obstack, | |
c5aa993b | 817 | (mcount + 1 - alloc_count) * sizeof (struct minimal_symbol)); |
c906108c SS |
818 | msymbols = (struct minimal_symbol *) |
819 | obstack_finish (&objfile->symbol_obstack); | |
820 | ||
821 | /* We also terminate the minimal symbol table with a "null symbol", | |
c5aa993b JM |
822 | which is *not* included in the size of the table. This makes it |
823 | easier to find the end of the table when we are handed a pointer | |
824 | to some symbol in the middle of it. Zero out the fields in the | |
825 | "null symbol" allocated at the end of the array. Note that the | |
826 | symbol count does *not* include this null symbol, which is why it | |
827 | is indexed by mcount and not mcount-1. */ | |
c906108c SS |
828 | |
829 | SYMBOL_NAME (&msymbols[mcount]) = NULL; | |
830 | SYMBOL_VALUE_ADDRESS (&msymbols[mcount]) = 0; | |
831 | MSYMBOL_INFO (&msymbols[mcount]) = NULL; | |
832 | MSYMBOL_TYPE (&msymbols[mcount]) = mst_unknown; | |
833 | SYMBOL_INIT_LANGUAGE_SPECIFIC (&msymbols[mcount], language_unknown); | |
834 | ||
835 | /* Attach the minimal symbol table to the specified objfile. | |
c5aa993b JM |
836 | The strings themselves are also located in the symbol_obstack |
837 | of this objfile. */ | |
c906108c | 838 | |
c5aa993b JM |
839 | objfile->minimal_symbol_count = mcount; |
840 | objfile->msymbols = msymbols; | |
c906108c SS |
841 | |
842 | /* Now walk through all the minimal symbols, selecting the newly added | |
c5aa993b | 843 | ones and attempting to cache their C++ demangled names. */ |
c906108c | 844 | |
c5aa993b | 845 | for (; mcount-- > 0; msymbols++) |
c906108c SS |
846 | { |
847 | SYMBOL_INIT_DEMANGLED_NAME (msymbols, &objfile->symbol_obstack); | |
848 | } | |
849 | } | |
850 | } | |
851 | ||
852 | /* Sort all the minimal symbols in OBJFILE. */ | |
853 | ||
854 | void | |
855 | msymbols_sort (objfile) | |
856 | struct objfile *objfile; | |
857 | { | |
858 | qsort (objfile->msymbols, objfile->minimal_symbol_count, | |
859 | sizeof (struct minimal_symbol), compare_minimal_symbols); | |
860 | } | |
861 | ||
862 | /* Check if PC is in a shared library trampoline code stub. | |
863 | Return minimal symbol for the trampoline entry or NULL if PC is not | |
864 | in a trampoline code stub. */ | |
865 | ||
866 | struct minimal_symbol * | |
867 | lookup_solib_trampoline_symbol_by_pc (pc) | |
868 | CORE_ADDR pc; | |
869 | { | |
870 | struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (pc); | |
871 | ||
872 | if (msymbol != NULL && MSYMBOL_TYPE (msymbol) == mst_solib_trampoline) | |
873 | return msymbol; | |
874 | return NULL; | |
875 | } | |
876 | ||
877 | /* If PC is in a shared library trampoline code stub, return the | |
878 | address of the `real' function belonging to the stub. | |
879 | Return 0 if PC is not in a trampoline code stub or if the real | |
880 | function is not found in the minimal symbol table. | |
881 | ||
882 | We may fail to find the right function if a function with the | |
883 | same name is defined in more than one shared library, but this | |
884 | is considered bad programming style. We could return 0 if we find | |
885 | a duplicate function in case this matters someday. */ | |
886 | ||
887 | CORE_ADDR | |
888 | find_solib_trampoline_target (pc) | |
889 | CORE_ADDR pc; | |
890 | { | |
891 | struct objfile *objfile; | |
892 | struct minimal_symbol *msymbol; | |
893 | struct minimal_symbol *tsymbol = lookup_solib_trampoline_symbol_by_pc (pc); | |
894 | ||
895 | if (tsymbol != NULL) | |
896 | { | |
897 | ALL_MSYMBOLS (objfile, msymbol) | |
c5aa993b JM |
898 | { |
899 | if (MSYMBOL_TYPE (msymbol) == mst_text | |
900 | && STREQ (SYMBOL_NAME (msymbol), SYMBOL_NAME (tsymbol))) | |
901 | return SYMBOL_VALUE_ADDRESS (msymbol); | |
902 | } | |
c906108c SS |
903 | } |
904 | return 0; | |
905 | } |