1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright (c) 1988 AT&T
24 * All Rights Reserved
25 *
26 * Copyright (c) 1991, 2010, Oracle and/or its affiliates. All rights reserved.
27 * Copyright (c) 2012, Joyent, Inc. All rights reserved.
28 */
29
30 /*
31 * Map file parsing and input section to output segment mapping.
32 */
33 #include <stdio.h>
34 #include <string.h>
35 #include <debug.h>
36 #include "msg.h"
37 #include "_libld.h"
38
39 /*
40 * Each time a section is placed, the function set_addralign()
41 * is called. This function performs:
42 *
43 * - if the section is from an external file, check if this is empty or not.
44 * If not, we know the segment this section will belong needs a program
45 * header. (Of course, the program is needed only if this section falls
46 * into a loadable segment.)
47 * - compute the Least Common Multiplier for setting the segment alignment.
48 */
49 static void
50 set_addralign(Ofl_desc *ofl, Os_desc *osp, Is_desc *isp)
51 {
52 Shdr *shdr = isp->is_shdr;
53
54 /* A discarded section has no influence on the output */
55 if (isp->is_flags & FLG_IS_DISCARD)
56 return;
57
58 /*
59 * If this section has data or will be assigned data
60 * later, mark this segment not-empty.
61 */
62 if ((shdr->sh_size != 0) ||
63 ((isp->is_flags & FLG_IS_EXTERNAL) == 0))
64 osp->os_sgdesc->sg_flags |= FLG_SG_PHREQ;
65
66 if ((ofl->ofl_dtflags_1 & DF_1_NOHDR) &&
67 (osp->os_sgdesc->sg_phdr).p_type != PT_LOAD)
68 return;
69
70 osp->os_sgdesc->sg_align =
71 ld_lcm(osp->os_sgdesc->sg_align, shdr->sh_addralign);
72 }
73
74 /*
75 * Return the first input descriptor for a given output descriptor,
76 * or NULL if there are none.
77 */
78
79 Is_desc *
80 ld_os_first_isdesc(Os_desc *osp)
81 {
82 int i;
83
84 for (i = 0; i < OS_ISD_NUM; i++) {
85 APlist *ap_isdesc = osp->os_isdescs[i];
86
87 if (aplist_nitems(ap_isdesc) > 0)
88 return ((Is_desc *)ap_isdesc->apl_data[0]);
89 }
90
91 return (NULL);
92 }
93
94 /*
95 * Attach an input section to an output section
96 *
97 * entry:
98 * ofl - File descriptor
99 * osp - Output section descriptor
100 * isp - Input section descriptor
101 * mapfile_sort - True (1) if segment supports mapfile specified ordering
102 * of otherwise unordered input sections, and False (0) otherwise.
103 *
104 * exit:
105 * - The input section has been attached to the output section
106 * - If the input section is a candidate for string table merging,
107 * then it is appended to the output section's list of merge
108 * candidates (os_mstridescs).
109 *
110 * On success, returns True (1). On failure, False (0).
111 */
112 static int
113 os_attach_isp(Ofl_desc *ofl, Os_desc *osp, Is_desc *isp, int mapfile_sort)
114 {
115 Aliste init_arritems;
116 int os_isdescs_idx, do_append = 1;
117
118 if ((isp->is_flags & FLG_IS_ORDERED) == 0) {
119 init_arritems = AL_CNT_OS_ISDESCS;
120 os_isdescs_idx = OS_ISD_DEFAULT;
121
122 /*
123 * If section ordering was specified for an unordered section
124 * via the mapfile, then search in the OS_ISD_DEFAULT list
125 * and insert it in the specified position. Ordered sections
126 * are placed in ascending order before unordered sections
127 * (sections with an is_ordndx value of zero).
128 *
129 * If no mapfile ordering was specified, we append it in
130 * the usual way below.
131 */
132 if (mapfile_sort && (isp->is_ordndx > 0)) {
133 APlist *ap_isdesc = osp->os_isdescs[OS_ISD_DEFAULT];
134 Aliste idx2;
135 Is_desc *isp2;
136
137 for (APLIST_TRAVERSE(ap_isdesc, idx2, isp2)) {
138 if (isp2->is_ordndx &&
139 (isp2->is_ordndx <= isp->is_ordndx))
140 continue;
141
142 if (aplist_insert(
143 &osp->os_isdescs[OS_ISD_DEFAULT],
144 isp, init_arritems, idx2) == NULL)
145 return (0);
146 do_append = 0;
147 break;
148 }
149 }
150 } else { /* Ordered section (via shdr flags) */
151 Word shndx;
152
153 /* SHF_ORDERED uses sh_info, SHF_LINK_ORDERED uses sh_link */
154 shndx = (isp->is_shdr->sh_flags & SHF_ORDERED) ?
155 isp->is_shdr->sh_info : isp->is_shdr->sh_link;
156
157 if (shndx == SHN_BEFORE) {
158 init_arritems = AL_CNT_OS_ISDESCS_BA;
159 os_isdescs_idx = OS_ISD_BEFORE;
160 } else if (shndx == SHN_AFTER) {
161 init_arritems = AL_CNT_OS_ISDESCS_BA;
162 os_isdescs_idx = OS_ISD_AFTER;
163 } else {
164 init_arritems = AL_CNT_OS_ISDESCS;
165 os_isdescs_idx = OS_ISD_ORDERED;
166 }
167 }
168
169 /*
170 * If we didn't insert a section into the default list using
171 * mapfile specified ordering above, then append the input
172 * section to the appropriate list.
173 */
174 if (do_append && aplist_append(&(osp->os_isdescs[os_isdescs_idx]),
175 isp, init_arritems) == NULL)
176 return (0);
177 isp->is_osdesc = osp;
178
179 /*
180 * A section can be merged if the following are true:
181 * - The SHF_MERGE|SHF_STRINGS flags must be set
182 * - String table compression must not be disabled (-znocompstrtab)
183 * - Mapfile ordering must not have been used.
184 * - The section must not be ordered via section header flags.
185 * - It must not be the generated section being built to
186 * replace the sections on this list.
187 */
188 if (((isp->is_shdr->sh_flags & (SHF_MERGE | SHF_STRINGS)) !=
189 (SHF_MERGE | SHF_STRINGS)) ||
190 ((ofl->ofl_flags1 & FLG_OF1_NCSTTAB) != 0) ||
191 !do_append ||
192 ((isp->is_flags & (FLG_IS_ORDERED | FLG_IS_GNSTRMRG)) != 0))
193 return (1);
194
195 /*
196 * Skip sections with (sh_entsize > 1) or (sh_addralign > 1).
197 *
198 * sh_entsize:
199 * We are currently only able to merge string tables containing
200 * strings with 1-byte (char) characters. Support for wide
201 * characters will require our string table compression code
202 * to be extended to handle larger character sizes.
203 *
204 * sh_addralign:
205 * Alignments greater than 1 would require our string table
206 * compression code to insert null bytes to move each
207 * string to the required alignment.
208 */
209 if ((isp->is_shdr->sh_entsize > 1) ||
210 (isp->is_shdr->sh_addralign > 1)) {
211 DBG_CALL(Dbg_sec_unsup_strmerge(ofl->ofl_lml, isp));
212 return (1);
213 }
214
215 if (aplist_append(&osp->os_mstrisdescs, isp,
216 AL_CNT_OS_MSTRISDESCS) == NULL)
217 return (0);
218
219 /*
220 * The SHF_MERGE|SHF_STRINGS flags tell us that the program that
221 * created the section intended it to be mergeable. The
222 * FLG_IS_INSTRMRG flag says that we have done validity testing
223 * and decided that it is safe to act on that hint.
224 */
225 isp->is_flags |= FLG_IS_INSTRMRG;
226
227 return (1);
228 }
229
230 /*
231 * Determine whether this input COMDAT section already exists for the associated
232 * output section. If so, then discard this input section. Otherwise, this
233 * must be the first COMDAT section, thus it is kept for future comparisons.
234 */
235 static uintptr_t
236 add_comdat(Ofl_desc *ofl, Os_desc *osp, Is_desc *isp)
237 {
238 Isd_node isd, *isdp;
239 avl_tree_t *avlt;
240 avl_index_t where;
241 Group_desc *gr;
242
243 /*
244 * Sections to which COMDAT groups apply are FLG_IS_COMDAT but are
245 * discarded separately by the group logic so should never be
246 * discarded here.
247 */
248 if ((isp->is_shdr->sh_flags & SHF_GROUP) &&
249 ((gr = ld_get_group(ofl, isp)) != NULL) &&
250 (gr->gd_data[0] & GRP_COMDAT))
251 return (1);
252
253 /*
254 * Create a COMDAT avl tree for this output section if required.
255 */
256 if ((avlt = osp->os_comdats) == NULL) {
257 if ((avlt = libld_calloc(sizeof (avl_tree_t), 1)) == NULL)
258 return (S_ERROR);
259 avl_create(avlt, isdavl_compare, sizeof (Isd_node),
260 SGSOFFSETOF(Isd_node, isd_avl));
261 osp->os_comdats = avlt;
262 }
263
264 /*
265 * A standard COMDAT section uses the section name as search key.
266 */
267 isd.isd_name = isp->is_name;
268 isd.isd_hash = sgs_str_hash(isd.isd_name);
269
270 if ((isdp = avl_find(avlt, &isd, &where)) != NULL) {
271 isp->is_osdesc = osp;
272
273 /*
274 * If this section hasn't already been identified as discarded,
275 * generate a suitable diagnostic.
276 */
277 if ((isp->is_flags & FLG_IS_DISCARD) == 0) {
278 isp->is_flags |= FLG_IS_DISCARD;
279 isp->is_comdatkeep = isdp->isd_isp;
280 DBG_CALL(Dbg_sec_discarded(ofl->ofl_lml, isp,
281 isdp->isd_isp));
282 }
283
284 /*
285 * A discarded section does not require assignment to an output
286 * section. However, if relaxed relocations have been enabled
287 * (either from -z relaxreloc, or asserted with .gnu.linkonce
288 * processing), then this section must still be assigned to an
289 * output section so that the sloppy relocation logic will have
290 * the information necessary to do its work.
291 */
292 return (0);
293 }
294
295 /*
296 * This is a new COMDAT section - so keep it.
297 */
298 if ((isdp = libld_calloc(sizeof (Isd_node), 1)) == NULL)
299 return (S_ERROR);
300
301 isdp->isd_name = isd.isd_name;
302 isdp->isd_hash = isd.isd_hash;
303 isdp->isd_isp = isp;
304
305 avl_insert(avlt, isdp, where);
306 return (1);
307 }
308
309 /*
310 * Determine whether a GNU group COMDAT section name follows the convention
311 *
312 * section-name.symbol-name
313 *
314 * Each section within the input file is compared to see if the full section
315 * name matches the beginning of the COMDAT section, with a following '.'.
316 * A pointer to the symbol name, starting with the '.' is returned so that the
317 * caller can strip off the required section name.
318 */
319 static char *
320 gnu_comdat_sym(Ifl_desc *ifl, Is_desc *gisp)
321 {
322 size_t ndx;
323
324 for (ndx = 1; ndx < ifl->ifl_shnum; ndx++) {
325 Is_desc *isp;
326 size_t ssize;
327
328 if (((isp = ifl->ifl_isdesc[ndx]) == NULL) ||
329 (isp == gisp) || (isp->is_name == NULL))
330 continue;
331
332 /*
333 * It's questionable whether this size should be cached in the
334 * Is_desc. However, this seems an infrequent operation and
335 * adding Is_desc members can escalate memory usage for large
336 * link-edits. For now, size the section name dynamically.
337 */
338 ssize = strlen(isp->is_name);
339 if ((strncmp(isp->is_name, gisp->is_name, ssize) == 0) &&
340 (gisp->is_name[ssize] == '.'))
341 return ((char *)&gisp->is_name[ssize]);
342 }
343 return (NULL);
344 }
345
346 /*
347 * GNU .gnu.linkonce sections follow a naming convention that indicates the
348 * required association with an output section. Determine whether this input
349 * section follows the convention, and if so return the appropriate output
350 * section name.
351 *
352 * .gnu.linkonce.b.* -> .bss
353 * .gnu.linkonce.d.* -> .data
354 * .gnu.linkonce.l.* -> .ldata
355 * .gnu.linkonce.lb.* -> .lbss
356 * .gnu.linkonce.lr.* -> .lrodata
357 * .gnu.linkonce.r.* -> .rodata
358 * .gnu.linkonce.s.* -> .sdata
359 * .gnu.linkonce.s2.* -> .sdata2
360 * .gnu.linkonce.sb.* -> .sbss
361 * .gnu.linkonce.sb2.* -> .sbss2
362 * .gnu.linkonce.t.* -> .text
363 * .gnu.linkonce.tb.* -> .tbss
364 * .gnu.linkonce.td.* -> .tdata
365 * .gnu.linkonce.wi.* -> .debug_info
366 */
367 #define NSTR_CH1(ch) (*(nstr + 1) == (ch))
368 #define NSTR_CH2(ch) (*(nstr + 2) == (ch))
369 #define NSTR_CH3(ch) (*(nstr + 3) == (ch))
370
371 static const char *
372 gnu_linkonce_sec(const char *ostr)
373 {
374 const char *nstr = &ostr[MSG_SCN_GNU_LINKONCE_SIZE];
375
376 switch (*nstr) {
377 case 'b':
378 if (NSTR_CH1('.'))
379 return (MSG_ORIG(MSG_SCN_BSS));
380 break;
381 case 'd':
382 if (NSTR_CH1('.'))
383 return (MSG_ORIG(MSG_SCN_DATA));
384 break;
385 case 'l':
386 if (NSTR_CH1('.'))
387 return (MSG_ORIG(MSG_SCN_LDATA));
388 else if (NSTR_CH1('b') && NSTR_CH2('.'))
389 return (MSG_ORIG(MSG_SCN_LBSS));
390 else if (NSTR_CH1('r') && NSTR_CH2('.'))
391 return (MSG_ORIG(MSG_SCN_LRODATA));
392 break;
393 case 'r':
394 if (NSTR_CH1('.'))
395 return (MSG_ORIG(MSG_SCN_RODATA));
396 break;
397 case 's':
398 if (NSTR_CH1('.'))
399 return (MSG_ORIG(MSG_SCN_SDATA));
400 else if (NSTR_CH1('2') && NSTR_CH2('.'))
401 return (MSG_ORIG(MSG_SCN_SDATA2));
402 else if (NSTR_CH1('b') && NSTR_CH2('.'))
403 return (MSG_ORIG(MSG_SCN_SBSS));
404 else if (NSTR_CH1('b') && NSTR_CH2('2') && NSTR_CH3('.'))
405 return (MSG_ORIG(MSG_SCN_SBSS2));
406 break;
407 case 't':
408 if (NSTR_CH1('.'))
409 return (MSG_ORIG(MSG_SCN_TEXT));
410 else if (NSTR_CH1('b') && NSTR_CH2('.'))
411 return (MSG_ORIG(MSG_SCN_TBSS));
412 else if (NSTR_CH1('d') && NSTR_CH2('.'))
413 return (MSG_ORIG(MSG_SCN_TDATA));
414 break;
415 case 'w':
416 if (NSTR_CH1('i') && NSTR_CH2('.'))
417 return (MSG_ORIG(MSG_SCN_DEBUG_INFO));
418 break;
419 default:
420 break;
421 }
422
423 /*
424 * No special name match found.
425 */
426 return (ostr);
427 }
428 #undef NSTR_CH1
429 #undef NSTR_CH2
430 #undef NSTR_CH3
431
432 /*
433 * The GNU link-editor maps sections generated by the GNU compiler separately
434 * due to -ffunction-sections, -fdata-sections or for other reasons into the
435 * "normal" section represented.
436 *
437 * Sections are named .<main>.<symbol> where <main> is the usual section to
438 * which it should be mapped, and <symbol> is providing the unique name for
439 * the original section. Both parts of the name may contain periods, in cases
440 * where the unique part of the name contains a '.' and/or the section it
441 * contributes to does (such as .data.rel.ro)
442 *
443 * .rodata.str* and .rodata.cst* are mapped to .rodata.
444 *
445 * As a further complication, the GNU link-editor may or may not merge
446 * .ctors.* and .dtors.* into init_array and fini_array, rather than ctors and
447 * dtors. We do not implement this at this time.
448 *
449 * The GNU link editor may also arrange for sections with .local in their name
450 * to be mapped as above, but grouped together. We do not implement this (and
451 * do not merge them at all, to make this clear)
452 *
453 * This table is processed in order. Longer mappings must come first.
454 */
455 static struct split_sec_mapping {
456 char *leader;
457 char *section;
458 boolean_t precise;
459 } split_sec_mapping[] = {
460 { ".bss.", ".bss", B_FALSE },
461 { ".ctors.", ".ctors", B_FALSE },
462 { ".data.rel.local.", ".data.rel.local", B_FALSE },
463 { ".data.rel.local", ".data.rel.local", B_TRUE },
464 { ".data.rel.ro.local.", ".data.rel.ro", B_FALSE },
465 { ".data.rel.ro.", ".data.rel.ro", B_FALSE },
466 { ".data.rel.ro", ".data.rel.ro", B_TRUE },
467 { ".data.rel.", ".data.rel", B_FALSE },
468 { ".data.rel", ".data.rel", B_TRUE },
469 { ".data.", ".data", B_FALSE },
470 { ".dtors.", ".dtors", B_FALSE },
471 { ".fini_array.", ".fini_array", B_FALSE },
472 { ".init_array.", ".init_array", B_FALSE },
473 { ".lbss.", ".lbss", B_FALSE },
474 { ".ldata.", ".ldata", B_FALSE },
475 { ".lrodata.", ".lrodata", B_FALSE },
476 /* This intentionally applies to .rodata.cstN and .rodata.strN, too */
477 { ".rodata.", ".rodata", B_FALSE },
478 { ".sbss2.", ".sbss2", B_FALSE },
479 { ".sbss.", ".sbss", B_FALSE },
480 { ".sdata2.", ".sdata2", B_FALSE },
481 { ".sdata.", ".sdata", B_FALSE },
482 { ".tbss.", ".tbss", B_FALSE },
483 { ".tdata.", ".tdata", B_FALSE },
484 { ".text.", ".text", B_FALSE },
485 { NULL, NULL, B_FALSE }
486 };
487
488 static const char *
489 gnu_split_sec(const char *ostr)
490 {
491 struct split_sec_mapping *mp;
492
493 for (mp = split_sec_mapping; mp->leader != NULL; mp++) {
494 if (mp->precise) {
495 if (strcmp(ostr, mp->leader) == 0)
496 return (mp->section);
497 } else if (strncmp(ostr, mp->leader, strlen(mp->leader)) == 0) {
498 return (mp->section);
499 }
500 }
501
502 return (ostr);
503 }
504
505 /*
506 * Initialize a path info buffer for use with ld_place_section().
507 *
508 * entry:
509 * ofl - Output descriptor
510 * ifl - Descriptor for input file, or NULL if there is none.
511 * info - Address of buffer to be initialized.
512 *
513 * exit:
514 * If this is an input file, and if the entrance criteria list
515 * contains at least one criteria that has a non-empty file string
516 * match list (ec_files), then the block pointed at by info is
517 * initialized, and info is returned.
518 *
519 * If there is no input file, and/or no entrance criteria containing
520 * a non-empty ec_files list, then NULL is returned. This is not
521 * an error --- the NULL is simply an optimization, understood by
522 * ld_place_path(), that allows it to skip unnecessary work.
523 */
524 Place_path_info *
525 ld_place_path_info_init(Ofl_desc *ofl, Ifl_desc *ifl, Place_path_info *info)
526 {
527 /*
528 * Return NULL if there is no input file (internally generated section)
529 * or if the entrance criteria list does not contain any items that will
530 * need to be compared to the path (all the ec_files lists are empty).
531 */
532 if ((ifl == NULL) || !(ofl->ofl_flags & FLG_OF_EC_FILES))
533 return (NULL);
534
535 info->ppi_path = ifl->ifl_name;
536 info->ppi_path_len = strlen(info->ppi_path);
537 info->ppi_isar = (ifl->ifl_flags & FLG_IF_EXTRACT) != 0;
538
539 /*
540 * The basename is the final segment of the path, equivalent to
541 * the path itself if there are no '/' delimiters.
542 */
543 info->ppi_bname = strrchr(info->ppi_path, '/');
544 if (info->ppi_bname == NULL)
545 info->ppi_bname = info->ppi_path;
546 else
547 info->ppi_bname++; /* Skip leading '/' */
548 info->ppi_bname_len =
549 info->ppi_path_len - (info->ppi_bname - info->ppi_path);
550
551 /*
552 * For an archive, the object name is the member name, which is
553 * enclosed in () at the end of the name string. Otherwise, it is
554 * the same as the basename.
555 */
556 if (info->ppi_isar) {
557 info->ppi_oname = strrchr(info->ppi_bname, '(');
558 /* There must be an archive member suffix delimited by parens */
559 assert((info->ppi_bname[info->ppi_bname_len - 1] == ')') &&
560 (info->ppi_oname != NULL));
561 info->ppi_oname++; /* skip leading '(' */
562 info->ppi_oname_len = info->ppi_bname_len -
563 (info->ppi_oname - info->ppi_bname + 1);
564 } else {
565 info->ppi_oname = info->ppi_bname;
566 info->ppi_oname_len = info->ppi_bname_len;
567 }
568
569 return (info);
570 }
571
572 /*
573 * Compare an input section path to the file comparison list the given
574 * entrance criteria.
575 *
576 * entry:
577 * path_info - A non-NULL Place_path_info block for the file
578 * containing the input section, initialized by
579 * ld_place_path_info_init()
580 * enp - Entrance criteria with a non-empty ec_files list of file
581 * comparisons to be carried out.
582 *
583 * exit:
584 * Return TRUE if a match is seen, and FALSE otherwise.
585 */
586 static Boolean
587 eval_ec_files(Place_path_info *path_info, Ent_desc *enp)
588 {
589 Aliste idx;
590 Ent_desc_file *edfp;
591 size_t cmp_len;
592 const char *cmp_str;
593
594 for (ALIST_TRAVERSE(enp->ec_files, idx, edfp)) {
595 Word type = edfp->edf_flags & TYP_ECF_MASK;
596
597 /*
598 * Determine the starting character, and # of characters,
599 * from the file path to compare against this entrance criteria
600 * file string.
601 */
602 if (type == TYP_ECF_OBJNAME) {
603 cmp_str = path_info->ppi_oname;
604 cmp_len = path_info->ppi_oname_len;
605 } else {
606 int ar_stat_diff = path_info->ppi_isar !=
607 ((edfp->edf_flags & FLG_ECF_ARMEMBER) != 0);
608
609 /*
610 * If the entrance criteria specifies an archive member
611 * and the file does not, then there can be no match.
612 */
613
614 if (ar_stat_diff && !path_info->ppi_isar)
615 continue;
616
617 if (type == TYP_ECF_PATH) {
618 cmp_str = path_info->ppi_path;
619 cmp_len = path_info->ppi_path_len;
620 } else { /* TYP_ECF_BASENAME */
621 cmp_str = path_info->ppi_bname;
622 cmp_len = path_info->ppi_bname_len;
623 }
624
625 /*
626 * If the entrance criteria does not specify an archive
627 * member and the file does, then a match just requires
628 * the paths (without the archive member) to match.
629 * Reduce the length to not include the ar member or
630 * the '(' that precedes it.
631 */
632 if (ar_stat_diff && path_info->ppi_isar)
633 cmp_len = path_info->ppi_oname - cmp_str - 1;
634 }
635
636 /*
637 * Compare the resulting string to the one from the
638 * entrance criteria.
639 */
640 if ((cmp_len == edfp->edf_name_len) &&
641 (strncmp(edfp->edf_name, cmp_str, cmp_len) == 0))
642 return (TRUE);
643 }
644
645 return (FALSE);
646 }
647
648 /*
649 * Replace the section header for the given input section with a new section
650 * header of the specified type. All values in the replacement header other
651 * than the type retain their previous values.
652 *
653 * entry:
654 * isp - Input section to replace
655 * sh_type - New section type to apply
656 *
657 * exit:
658 * Returns the pointer to the new section header on success, and
659 * NULL for failure.
660 */
661 static Shdr *
662 isp_convert_type(Is_desc *isp, Word sh_type)
663 {
664 Shdr *shdr;
665
666 if ((shdr = libld_malloc(sizeof (Shdr))) == NULL)
667 return (NULL);
668 *shdr = *isp->is_shdr;
669 isp->is_shdr = shdr;
670 shdr->sh_type = sh_type;
671 return (shdr);
672 }
673
674 /*
675 * Issue a fatal warning for the given .eh_frame section, which
676 * cannot be merged with the existing .eh_frame output section.
677 */
678 static void
679 eh_frame_muldef(Ofl_desc *ofl, Is_desc *isp)
680 {
681 Sg_desc *sgp;
682 Is_desc *isp1;
683 Os_desc *osp;
684 Aliste idx1, idx2, idx3;
685
686 /*
687 * Locate the .eh_frame output section, and use the first section
688 * assigned to it in the error message. The user can then compare
689 * the two sections to determine what attribute prevented the merge.
690 */
691 for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) {
692 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) {
693 if ((osp->os_flags & FLG_OS_EHFRAME) == 0)
694 continue;
695
696 for (idx3 = 0; idx3 < OS_ISD_NUM; idx3++) {
697 APlist *lst = osp->os_isdescs[idx3];
698
699 if (aplist_nitems(lst) == 0)
700 continue;
701
702 isp1 = lst->apl_data[0];
703 ld_eprintf(ofl, ERR_FATAL,
704 MSG_INTL(MSG_UPD_MULEHFRAME),
705 isp1->is_file->ifl_name,
706 EC_WORD(isp1->is_scnndx), isp1->is_name,
707 isp->is_file->ifl_name,
708 EC_WORD(isp->is_scnndx), isp->is_name);
709 return;
710 }
711 }
712 }
713 }
714
715 /*
716 * Place a section into the appropriate segment and output section.
717 *
718 * entry:
719 * ofl - File descriptor
720 * isp - Input section descriptor of section to be placed.
721 * path_info - NULL, or pointer to Place_path_info buffer initialized
722 * by ld_place_path_info_init() for the file associated to isp,
723 * for use in processing entrance criteria with non-empty
724 * file matching string list (ec_files)
725 * ident - Section identifier, used to order sections relative to
726 * others within the output segment.
727 * alt_os_name - If non-NULL, the name of the output section to place
728 * isp into. If NULL, input sections go to an output section
729 * with the same name as the input section.
730 */
731 Os_desc *
732 ld_place_section(Ofl_desc *ofl, Is_desc *isp, Place_path_info *path_info,
733 int ident, const char *alt_os_name)
734 {
735 Ent_desc *enp;
736 Sg_desc *sgp;
737 Os_desc *osp;
738 Aliste idx1, iidx;
739 int os_ndx;
740 Shdr *shdr = isp->is_shdr;
741 Xword shflagmask, shflags = shdr->sh_flags;
742 Ifl_desc *ifl = isp->is_file;
743 char *oname, *sname;
744 uint_t onamehash;
745 Boolean is_ehframe = (isp->is_flags & FLG_IS_EHFRAME) != 0;
746
747 /*
748 * Define any sections that must be thought of as referenced. These
749 * sections may not be referenced externally in a manner ld(1) can
750 * discover, but they must be retained (ie. not removed by -zignore).
751 */
752 static const Msg RefSecs[] = {
753 MSG_SCN_INIT, /* MSG_ORIG(MSG_SCN_INIT) */
754 MSG_SCN_FINI, /* MSG_ORIG(MSG_SCN_FINI) */
755 MSG_SCN_EX_RANGES, /* MSG_ORIG(MSG_SCN_EX_RANGES) */
756 MSG_SCN_EX_SHARED, /* MSG_ORIG(MSG_SCN_EX_SHARED) */
757 MSG_SCN_CTORS, /* MSG_ORIG(MSG_SCN_CTORS) */
758 MSG_SCN_DTORS, /* MSG_ORIG(MSG_SCN_DTORS) */
759 MSG_SCN_EHFRAME, /* MSG_ORIG(MSG_SCN_EHFRAME) */
760 MSG_SCN_EHFRAME_HDR, /* MSG_ORIG(MSG_SCN_EHFRAME_HDR) */
761 MSG_SCN_JCR, /* MSG_ORIG(MSG_SCN_JCR) */
762 MSG_SCN_INITARRAY, /* MSG_ORIG(MSG_SCN_INITARRAY) */
763 MSG_SCN_FINIARRAY, /* MSG_ORIG(MSG_SCN_FINIARRAY) */
764 MSG_SCN_PREINITARRAY, /* MSG_ORIG(MSG_SCN_PREINITARRAY) */
765 0
766 };
767
768 DBG_CALL(Dbg_sec_in(ofl->ofl_lml, isp));
769
770 /*
771 * If this section identifies group members, or this section indicates
772 * that it is a member of a group, determine whether the section is
773 * still required.
774 */
775 if ((shflags & SHF_GROUP) || (shdr->sh_type == SHT_GROUP)) {
776 Group_desc *gdesc;
777
778 if ((gdesc = ld_get_group(ofl, isp)) != NULL) {
779 DBG_CALL(Dbg_sec_group(ofl->ofl_lml, isp, gdesc));
780
781 /*
782 * If this group has been replaced by another group,
783 * then this section needs to be discarded.
784 */
785 if (gdesc->gd_oisc) {
786 isp->is_flags |= FLG_IS_DISCARD;
787
788 /*
789 * Since we're discarding the section, we
790 * can skip assigning it to an output section.
791 * The exception is that if the user
792 * specifies -z relaxreloc, then
793 * we need to assign the output section so
794 * that the sloppy relocation logic will have
795 * the information necessary to do its work.
796 */
797 if (!(ofl->ofl_flags1 & FLG_OF1_RLXREL))
798 return (NULL);
799 }
800 }
801
802 /*
803 * SHT_GROUP sections can only be included into relocatable
804 * objects.
805 */
806 if (shdr->sh_type == SHT_GROUP) {
807 if ((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) {
808 isp->is_flags |= FLG_IS_DISCARD;
809 return (NULL);
810 }
811 }
812 }
813
814 /*
815 * Always assign SHF_TLS sections to the DATA segment (and then the
816 * PT_TLS embedded inside of there).
817 */
818 if (shflags & SHF_TLS)
819 shflags |= SHF_WRITE;
820
821 /*
822 * Traverse the entrance criteria list searching for a segment that
823 * matches the input section we have. If an entrance criterion is set
824 * then there must be an exact match. If we complete the loop without
825 * finding a segment, then sgp will be NULL.
826 */
827 sgp = NULL;
828 for (APLIST_TRAVERSE(ofl->ofl_ents, idx1, enp)) {
829
830 /* Disabled segments are not available for assignment */
831 if (enp->ec_segment->sg_flags & FLG_SG_DISABLED)
832 continue;
833
834 /*
835 * If an entrance criteria doesn't have any of its fields
836 * set, it will match any section it is tested against.
837 * We set the FLG_EC_CATCHALL flag on these, primarily because
838 * it helps readers of our debug output to understand what
839 * the criteria means --- otherwise the user would just see
840 * that every field is 0, but might not understand the
841 * significance of that.
842 *
843 * Given that we set this flag, we can use it here as an
844 * optimization to short circuit all of the tests in this
845 * loop. Note however, that if we did not do this, the end
846 * result would be the same --- the empty criteria will sail
847 * past the following tests and reach the end of the loop.
848 */
849 if (enp->ec_flags & FLG_EC_CATCHALL) {
850 sgp = enp->ec_segment;
851 break;
852 }
853
854 if (enp->ec_type && (enp->ec_type != shdr->sh_type))
855 continue;
856 if (enp->ec_attrmask &&
857 /* LINTED */
858 (enp->ec_attrmask & enp->ec_attrbits) !=
859 (enp->ec_attrmask & shflags))
860 continue;
861 if (enp->ec_is_name &&
862 (strcmp(enp->ec_is_name, isp->is_name) != 0))
863 continue;
864
865 if ((alist_nitems(enp->ec_files) > 0) &&
866 ((path_info == NULL) || !eval_ec_files(path_info, enp)))
867 continue;
868
869 /* All entrance criteria tests passed */
870 sgp = enp->ec_segment;
871 break;
872 }
873
874 /*
875 * The final entrance criteria record is a FLG_EC_CATCHALL that points
876 * at the final predefined segment "extra", and this final segment is
877 * tagged FLG_SG_NODISABLE. Therefore, the above loop must always find
878 * a segment.
879 */
880 assert(sgp != NULL);
881
882 /*
883 * Transfer the input section sorting key from the entrance criteria
884 * to the input section. A non-zero value means that the section
885 * will be sorted on this key amoung the other sections that have a
886 * non-zero key. These sorted sections are collectively placed at the
887 * head of the output section.
888 *
889 * If the sort key is 0, the section is placed after the sorted
890 * sections in the order they are encountered.
891 */
892 isp->is_ordndx = enp->ec_ordndx;
893
894 /* Remember that this entrance criteria has placed a section */
895 enp->ec_flags |= FLG_EC_USED;
896
897 /*
898 * If our caller has supplied an alternative name for the output
899 * section, then we defer to their request. Otherwise, the default
900 * is to use the same name as that of the input section being placed.
901 *
902 * The COMDAT, SHT_GROUP and GNU name translations that follow have
903 * the potential to alter this initial name.
904 */
905 oname = (char *)((alt_os_name == NULL) ? isp->is_name : alt_os_name);
906
907 /*
908 * Solaris section names may follow the convention:
909 *
910 * section-name%symbol-name
911 *
912 * This convention has been used to order the layout of sections within
913 * segments for objects built with the compilers -xF option. However,
914 * the final object should not contain individual section headers for
915 * all such input sections, instead the symbol name is stripped from the
916 * name to establish the final output section name.
917 *
918 * This convention has also been followed for COMDAT and sections
919 * identified though SHT_GROUP data.
920 *
921 * Strip out the % from the section name for:
922 * - Non-relocatable objects
923 * - Relocatable objects if input section sorting is
924 * in force for the segment in question.
925 */
926 if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) ||
927 (sgp->sg_flags & FLG_SG_IS_ORDER)) {
928 if ((sname = strchr(isp->is_name, '%')) != NULL) {
929 size_t size = sname - isp->is_name;
930
931 if ((oname = libld_malloc(size + 1)) == NULL)
932 return ((Os_desc *)S_ERROR);
933 (void) strncpy(oname, isp->is_name, size);
934 oname[size] = '\0';
935 DBG_CALL(Dbg_sec_redirected(ofl->ofl_lml, isp, oname));
936 }
937 }
938
939 /*
940 * When building relocatable objects, we must not redirect COMDAT
941 * section names into their outputs, such that our output object may
942 * be successfully used as an input object also requiring COMDAT
943 * processing
944 */
945
946 /*
947 * GNU section names may follow the convention:
948 *
949 * .gnu.linkonce.*
950 *
951 * The .gnu.linkonce is a section naming convention that indicates a
952 * COMDAT requirement. Determine whether this section follows the GNU
953 * pattern, and if so, determine whether this section should be
954 * discarded or retained. The comparison of is_name[1] with 'g'
955 * is an optimization to skip using strncmp() too much. This is safe,
956 * because we know the name is not NULL, and therefore must have
957 * at least one character plus a NULL termination.
958 */
959 if ((isp->is_name == oname) && (isp->is_name[1] == 'g') &&
960 (strncmp(MSG_ORIG(MSG_SCN_GNU_LINKONCE), isp->is_name,
961 MSG_SCN_GNU_LINKONCE_SIZE) == 0)) {
962 if ((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) {
963 if ((oname = (char *)gnu_linkonce_sec(isp->is_name)) !=
964 isp->is_name) {
965 DBG_CALL(Dbg_sec_redirected(ofl->ofl_lml, isp,
966 oname));
967 }
968 }
969
970 /*
971 * Explicitly identify this section type as COMDAT. Also,
972 * enable relaxed relocation processing, as this is typically
973 * a requirement with .gnu.linkonce sections.
974 */
975 isp->is_flags |= FLG_IS_COMDAT;
976 if ((ofl->ofl_flags1 & FLG_OF1_NRLXREL) == 0)
977 ofl->ofl_flags1 |= FLG_OF1_RLXREL;
978 DBG_CALL(Dbg_sec_gnu_comdat(ofl->ofl_lml, isp, TRUE,
979 (ofl->ofl_flags1 & FLG_OF1_RLXREL) != 0));
980 }
981
982 /*
983 * GNU section names may also follow the convention:
984 *
985 * section-name.symbol-name
986 *
987 * This convention is used when defining SHT_GROUP sections of type
988 * COMDAT. Thus, any group processing will have discovered any group
989 * sections, and this identification can be triggered by a pattern
990 * match section names.
991 */
992 if ((isp->is_name == oname) && (isp->is_flags & FLG_IS_COMDAT) &&
993 ((sname = gnu_comdat_sym(ifl, isp)) != NULL)) {
994 size_t size = sname - isp->is_name;
995
996 if ((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) {
997 if ((oname = libld_malloc(size + 1)) == NULL)
998 return ((Os_desc *)S_ERROR);
999 (void) strncpy(oname, isp->is_name, size);
1000 oname[size] = '\0';
1001 DBG_CALL(Dbg_sec_redirected(ofl->ofl_lml, isp, oname));
1002 }
1003
1004 /*
1005 * Enable relaxed relocation processing, as this is
1006 * typically a requirement with GNU COMDAT sections.
1007 */
1008 if ((ofl->ofl_flags1 & FLG_OF1_NRLXREL) == 0) {
1009 ofl->ofl_flags1 |= FLG_OF1_RLXREL;
1010 DBG_CALL(Dbg_sec_gnu_comdat(ofl->ofl_lml, isp,
1011 FALSE, TRUE));
1012 }
1013 }
1014
1015 /*
1016 * GNU section names named section-name.symbol-name which are not
1017 * members of COMDAT groups are merged according to the behaviour of
1018 * the GNU link-editor.
1019 *
1020 * See the description of gnu_split_sec().
1021 */
1022 if (((ofl->ofl_flags & FLG_OF_RELOBJ) == 0) &&
1023 (isp->is_name == oname) &&
1024 ((oname = (char *)gnu_split_sec(oname)) != isp->is_name)) {
1025 DBG_CALL(Dbg_sec_redirected(ofl->ofl_lml, isp, oname));
1026 }
1027
1028 /*
1029 * Assign a hash value now that the output section name has been
1030 * finalized.
1031 */
1032 onamehash = sgs_str_hash(oname);
1033
1034 /*
1035 * Determine if output section ordering is turned on. If so, return
1036 * the appropriate ordering index for the section. This information
1037 * is derived from the Sg_desc->sg_os_order list that was built
1038 * up from the Mapfile.
1039 *
1040 * A value of 0 for os_ndx means that the section is not sorted
1041 * (i.e. is not found in the sg_os_order). The items in sg_os_order
1042 * are in the desired sort order, so adding 1 to their alist index
1043 * gives a suitable index for sorting.
1044 */
1045 os_ndx = 0;
1046 if (alist_nitems(sgp->sg_os_order) > 0) {
1047 Sec_order *scop;
1048
1049 for (ALIST_TRAVERSE(sgp->sg_os_order, idx1, scop)) {
1050 if (strcmp(scop->sco_secname, oname) == 0) {
1051 scop->sco_flags |= FLG_SGO_USED;
1052 os_ndx = idx1 + 1;
1053 break;
1054 }
1055 }
1056 }
1057
1058 /*
1059 * Mask of section header flags to ignore when matching sections. We
1060 * are more strict with relocatable objects, ignoring only the order
1061 * flags, and keeping sections apart if they differ otherwise. This
1062 * follows the policy that sections in a relative object should only
1063 * be merged if their flags are the same, and avoids destroying
1064 * information prematurely. For final products however, we ignore all
1065 * flags that do not prevent a merge.
1066 */
1067 shflagmask =
1068 (ofl->ofl_flags & FLG_OF_RELOBJ) ? ALL_SHF_ORDER : ALL_SHF_IGNORE;
1069
1070 /*
1071 * Traverse the input section list for the output section we have been
1072 * assigned. If we find a matching section simply add this new section.
1073 */
1074 iidx = 0;
1075 for (APLIST_TRAVERSE(sgp->sg_osdescs, idx1, osp)) {
1076 Shdr *os_shdr = osp->os_shdr;
1077
1078 /*
1079 * An input section matches an output section if:
1080 * - The ident values match
1081 * - The names match
1082 * - Not a GROUP section
1083 * - Not a DTrace dof section
1084 * - Section types match
1085 * - Matching section flags, after screening out the
1086 * shflagmask flags.
1087 *
1088 * Section types are considered to match if any one of
1089 * the following are true:
1090 * - The type codes are the same
1091 * - Both are .eh_frame sections (regardless of type code)
1092 * - The input section is COMDAT, and the output section
1093 * is SHT_PROGBITS.
1094 */
1095 if ((ident == osp->os_identndx) &&
1096 (ident != ld_targ.t_id.id_rel) &&
1097 (onamehash == osp->os_namehash) &&
1098 (shdr->sh_type != SHT_GROUP) &&
1099 (shdr->sh_type != SHT_SUNW_dof) &&
1100 ((shdr->sh_type == os_shdr->sh_type) ||
1101 (is_ehframe && (osp->os_flags & FLG_OS_EHFRAME)) ||
1102 ((shdr->sh_type == SHT_SUNW_COMDAT) &&
1103 (os_shdr->sh_type == SHT_PROGBITS))) &&
1104 ((shflags & ~shflagmask) ==
1105 (os_shdr->sh_flags & ~shflagmask)) &&
1106 (strcmp(oname, osp->os_name) == 0)) {
1107 uintptr_t err;
1108
1109 /*
1110 * Process any COMDAT section, keeping the first and
1111 * discarding all others.
1112 */
1113 if ((isp->is_flags & FLG_IS_COMDAT) &&
1114 ((err = add_comdat(ofl, osp, isp)) != 1))
1115 return ((Os_desc *)err);
1116
1117 /*
1118 * Set alignment
1119 */
1120 set_addralign(ofl, osp, isp);
1121
1122 /*
1123 * If this section is a non-empty TLS section indicate
1124 * that a PT_TLS program header is required.
1125 */
1126 if ((shflags & SHF_TLS) && shdr->sh_size &&
1127 ((ofl->ofl_flags & FLG_OF_RELOBJ) == 0))
1128 ofl->ofl_flags |= FLG_OF_TLSPHDR;
1129
1130 /*
1131 * Insert the input section descriptor on the proper
1132 * output section descriptor list.
1133 *
1134 * If this segment requires input section ordering,
1135 * honor any mapfile specified ordering for otherwise
1136 * unordered sections by setting the mapfile_sort
1137 * argument of os_attach_isp() to True.
1138 */
1139
1140 if (os_attach_isp(ofl, osp, isp,
1141 (sgp->sg_flags & FLG_SG_IS_ORDER) != 0) == 0)
1142 return ((Os_desc *)S_ERROR);
1143
1144 /*
1145 * If this input section and file is associated to an
1146 * artificially referenced output section, make sure
1147 * they are marked as referenced also. This ensures
1148 * that this input section and file isn't eliminated
1149 * when -zignore is in effect.
1150 *
1151 * See -zignore comments when creating a new output
1152 * section below.
1153 */
1154 if (((ifl &&
1155 (ifl->ifl_flags & FLG_IF_IGNORE)) || DBG_ENABLED) &&
1156 (osp->os_flags & FLG_OS_SECTREF)) {
1157 isp->is_flags |= FLG_IS_SECTREF;
1158 if (ifl)
1159 ifl->ifl_flags |= FLG_IF_FILEREF;
1160 }
1161
1162 DBG_CALL(Dbg_sec_added(ofl->ofl_lml, osp, sgp));
1163 return (osp);
1164 }
1165
1166 /*
1167 * Do we need to worry about section ordering?
1168 */
1169 if (os_ndx) {
1170 if (osp->os_ordndx) {
1171 if (os_ndx < osp->os_ordndx)
1172 /* insert section here. */
1173 break;
1174 else {
1175 iidx = idx1 + 1;
1176 continue;
1177 }
1178 } else {
1179 /* insert section here. */
1180 break;
1181 }
1182 } else if (osp->os_ordndx) {
1183 iidx = idx1 + 1;
1184 continue;
1185 }
1186
1187 /*
1188 * If the new sections identifier is less than that of the
1189 * present input section we need to insert the new section
1190 * at this point.
1191 */
1192 if (ident < osp->os_identndx)
1193 break;
1194
1195 iidx = idx1 + 1;
1196 }
1197
1198 /*
1199 * We are adding a new output section. Update the section header
1200 * count and associated string size.
1201 *
1202 * If the input section triggering this output section has been marked
1203 * for discard, and if no other non-discarded input section comes along
1204 * to join it, then we will over count. We cannot know if this will
1205 * happen or not until all input is seen. Set FLG_OF_AJDOSCNT to
1206 * trigger a final count readjustment.
1207 */
1208 if (isp->is_flags & FLG_IS_DISCARD)
1209 ofl->ofl_flags |= FLG_OF_ADJOSCNT;
1210 ofl->ofl_shdrcnt++;
1211 if (st_insert(ofl->ofl_shdrsttab, oname) == -1)
1212 return ((Os_desc *)S_ERROR);
1213
1214 /*
1215 * Create a new output section descriptor.
1216 */
1217 if ((osp = libld_calloc(sizeof (Os_desc), 1)) == NULL)
1218 return ((Os_desc *)S_ERROR);
1219 if ((osp->os_shdr = libld_calloc(sizeof (Shdr), 1)) == NULL)
1220 return ((Os_desc *)S_ERROR);
1221
1222 /*
1223 * Convert COMDAT section to PROGBITS as this the first section of the
1224 * output section. Save any COMDAT section for later processing, as
1225 * additional COMDAT sections that match this section need discarding.
1226 */
1227 if ((shdr->sh_type == SHT_SUNW_COMDAT) &&
1228 ((shdr = isp_convert_type(isp, SHT_PROGBITS)) == NULL))
1229 return ((Os_desc *)S_ERROR);
1230 if ((isp->is_flags & FLG_IS_COMDAT) &&
1231 (add_comdat(ofl, osp, isp) == S_ERROR))
1232 return ((Os_desc *)S_ERROR);
1233
1234 if (is_ehframe) {
1235 /*
1236 * Executable or sharable objects can have at most a single
1237 * .eh_frame section. Detect attempts to create more than
1238 * one. This occurs if the input sections have incompatible
1239 * attributes.
1240 */
1241 if ((ofl->ofl_flags & FLG_OF_EHFRAME) &&
1242 !(ofl->ofl_flags & FLG_OF_RELOBJ)) {
1243 eh_frame_muldef(ofl, isp);
1244 return ((Os_desc *)S_ERROR);
1245 }
1246 ofl->ofl_flags |= FLG_OF_EHFRAME;
1247
1248 /*
1249 * For .eh_frame sections, we always set the type to be the
1250 * type specified by the ABI. This allows .eh_frame sections
1251 * of type SHT_PROGBITS to be correctly merged with .eh_frame
1252 * sections of the ABI-defined type (e.g. SHT_AMD64_UNWIND),
1253 * with the output being of the ABI-defined type.
1254 */
1255 osp->os_shdr->sh_type = ld_targ.t_m.m_sht_unwind;
1256 } else {
1257 osp->os_shdr->sh_type = shdr->sh_type;
1258 }
1259
1260 osp->os_shdr->sh_flags = shdr->sh_flags;
1261 osp->os_shdr->sh_entsize = shdr->sh_entsize;
1262 osp->os_name = oname;
1263 osp->os_namehash = onamehash;
1264 osp->os_ordndx = os_ndx;
1265 osp->os_sgdesc = sgp;
1266 if (is_ehframe)
1267 osp->os_flags |= FLG_OS_EHFRAME;
1268
1269 if (ifl && (shdr->sh_type == SHT_PROGBITS)) {
1270 /*
1271 * Try to preserve the intended meaning of sh_link/sh_info.
1272 * See the translate_link() in update.c.
1273 */
1274 osp->os_shdr->sh_link = shdr->sh_link;
1275 if (shdr->sh_flags & SHF_INFO_LINK)
1276 osp->os_shdr->sh_info = shdr->sh_info;
1277 }
1278
1279 /*
1280 * When -zignore is in effect, user supplied sections and files that are
1281 * not referenced from other sections, are eliminated from the object
1282 * being produced. Some sections, although unreferenced, are special,
1283 * and must not be eliminated. Determine if this new output section is
1284 * one of those special sections, and if so mark it artificially as
1285 * referenced. Any input section and file associated to this output
1286 * section is also be marked as referenced, and thus won't be eliminated
1287 * from the final output.
1288 */
1289 if (ifl && ((ofl->ofl_flags1 & FLG_OF1_IGNPRC) || DBG_ENABLED)) {
1290 const Msg *refsec;
1291
1292 for (refsec = RefSecs; *refsec; refsec++) {
1293 if (strcmp(osp->os_name, MSG_ORIG(*refsec)) == 0) {
1294 osp->os_flags |= FLG_OS_SECTREF;
1295
1296 if ((ifl->ifl_flags & FLG_IF_IGNORE) ||
1297 DBG_ENABLED) {
1298 isp->is_flags |= FLG_IS_SECTREF;
1299 ifl->ifl_flags |= FLG_IF_FILEREF;
1300 }
1301 break;
1302 }
1303 }
1304 }
1305
1306 /*
1307 * Sections of type SHT_GROUP are added to the ofl->ofl_osgroups list,
1308 * so that they can be updated as a group later.
1309 */
1310 if ((shdr->sh_type == SHT_GROUP) &&
1311 ((isp->is_flags & FLG_IS_DISCARD) == 0) &&
1312 (aplist_append(&ofl->ofl_osgroups, osp,
1313 AL_CNT_OFL_OSGROUPS) == NULL))
1314 return ((Os_desc *)S_ERROR);
1315
1316 /*
1317 * If this section is a non-empty TLS section indicate that a PT_TLS
1318 * program header is required.
1319 */
1320 if ((shflags & SHF_TLS) && shdr->sh_size &&
1321 ((ofl->ofl_flags & FLG_OF_RELOBJ) == 0))
1322 ofl->ofl_flags |= FLG_OF_TLSPHDR;
1323
1324 /*
1325 * If a non-allocatable section is going to be put into a loadable
1326 * segment then turn on the allocate bit for this section and warn the
1327 * user that we have done so. This could only happen through the use
1328 * of a mapfile.
1329 */
1330 if ((sgp->sg_phdr.p_type == PT_LOAD) &&
1331 ((osp->os_shdr->sh_flags & SHF_ALLOC) == 0)) {
1332 ld_eprintf(ofl, ERR_WARNING, MSG_INTL(MSG_SCN_NONALLOC),
1333 ofl->ofl_name, osp->os_name, sgp->sg_name);
1334 osp->os_shdr->sh_flags |= SHF_ALLOC;
1335 }
1336
1337 /*
1338 * Retain this sections identifier for future comparisons when placing
1339 * a section (after all sections have been processed this variable will
1340 * be used to hold the sections symbol index as we don't need to retain
1341 * the identifier any more).
1342 */
1343 osp->os_identndx = ident;
1344
1345 /*
1346 * Set alignment.
1347 */
1348 set_addralign(ofl, osp, isp);
1349
1350 if (os_attach_isp(ofl, osp, isp, 0) == 0)
1351 return ((Os_desc *)S_ERROR);
1352
1353 DBG_CALL(Dbg_sec_created(ofl->ofl_lml, osp, sgp));
1354
1355 /*
1356 * Insert the new section at the offset given by iidx. If no position
1357 * for it was identified above, this will be index 0, causing the new
1358 * section to be prepended to the beginning of the section list.
1359 * Otherwise, it is the index following the section that was identified.
1360 */
1361 if (aplist_insert(&sgp->sg_osdescs, osp, AL_CNT_SG_OSDESC,
1362 iidx) == NULL)
1363 return ((Os_desc *)S_ERROR);
1364 return (osp);
1365 }