outfile.c revision 9273:9a0603d78ad3
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 2009 Sun Microsystems, Inc.  All rights reserved.
27 * Use is subject to license terms.
28 */
29
30/*
31 * This file contains the functions responsible for opening the output file
32 * image, associating the appropriate input elf structures with the new image,
33 * and obtaining new elf structures to define the new image.
34 */
35#include	<stdio.h>
36#include	<sys/stat.h>
37#include	<fcntl.h>
38#include	<link.h>
39#include	<errno.h>
40#include	<string.h>
41#include	<limits.h>
42#include	<debug.h>
43#include	<unistd.h>
44#include	"msg.h"
45#include	"_libld.h"
46
47/*
48 * Determine a least common multiplier.  Input sections contain an alignment
49 * requirement, which elf_update() uses to insure that the section is aligned
50 * correctly off of the base of the elf image.  We must also insure that the
51 * sections mapping is congruent with this alignment requirement.  For each
52 * input section associated with a loadable segment determine whether the
53 * segments alignment must be adjusted to compensate for a sections alignment
54 * requirements.
55 */
56Xword
57ld_lcm(Xword a, Xword b)
58{
59	Xword	_r, _a, _b;
60
61	if ((_a = a) == 0)
62		return (b);
63	if ((_b = b) == 0)
64		return (a);
65
66	if (_a > _b)
67		_a = b, _b = a;
68	while ((_r = _b % _a) != 0)
69		_b = _a, _a = _r;
70	return ((a / _a) * b);
71}
72
73/*
74 * Open the output file and insure the correct access modes.
75 */
76uintptr_t
77ld_open_outfile(Ofl_desc * ofl)
78{
79	mode_t		mode;
80	struct stat	status;
81
82	/*
83	 * Determine the required file mode from the type of output file we
84	 * are creating.
85	 */
86	mode = (ofl->ofl_flags & (FLG_OF_EXEC | FLG_OF_SHAROBJ))
87	    ? 0777 : 0666;
88
89	/* Determine if the output file already exists */
90	if (stat(ofl->ofl_name, &status) == 0) {
91		if ((status.st_mode & S_IFMT) != S_IFREG) {
92			/*
93			 * It is not a regular file, so don't delete it
94			 * or allow it to be deleted.  This allows root
95			 * users to specify /dev/null output file for
96			 * verification links.
97			 */
98			ofl->ofl_flags1 |= FLG_OF1_NONREG;
99		} else {
100			/*
101			 * It's a regular file, so unlink it. In standard
102			 * Unix fashion, the old file will continue to
103			 * exist until its link count drops to 0 and no
104			 * process has the file open. In the meantime, we
105			 * create a new file (inode) under the same name,
106			 * available for new use.
107			 *
108			 * The advantage of this policy is that creating
109			 * a new executable or sharable library does not
110			 * corrupt existing processes using the old file.
111			 * A possible disadvantage is that if the existing
112			 * file has a (link_count > 1), the other names will
113			 * continue to reference the old inode, thus
114			 * breaking the link.
115			 *
116			 * A subtlety here is that POSIX says we are not
117			 * supposed to replace a non-writable file, which
118			 * is something that unlink() is happy to do. The
119			 * only 100% reliable test against this is to open
120			 * the file for non-destructive write access. If the
121			 * open succeeds, we are clear to unlink it, and if
122			 * not, then the error generated is the error we
123			 * need to report.
124			 */
125			if ((ofl->ofl_fd = open(ofl->ofl_name, O_RDWR,
126			    mode)) < 0) {
127				int	err = errno;
128
129				if (err != ENOENT) {
130					eprintf(ofl->ofl_lml, ERR_FATAL,
131					    MSG_INTL(MSG_SYS_OPEN),
132					    ofl->ofl_name, strerror(err));
133					return (S_ERROR);
134				}
135			} else {
136				(void) close(ofl->ofl_fd);
137			}
138
139			if ((unlink(ofl->ofl_name) == -1) &&
140			    (errno != ENOENT)) {
141				int err = errno;
142
143				eprintf(ofl->ofl_lml, ERR_FATAL,
144				    MSG_INTL(MSG_SYS_UNLINK),
145				    ofl->ofl_name, strerror(err));
146				return (S_ERROR);
147			}
148		}
149	}
150
151	/*
152	 * Open (or create) the output file name (ofl_fd acts as a global
153	 * flag to ldexit() signifying whether the output file should be
154	 * removed or not on error).
155	 */
156	if ((ofl->ofl_fd = open(ofl->ofl_name, O_RDWR | O_CREAT | O_TRUNC,
157	    mode)) < 0) {
158		int	err = errno;
159
160		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_SYS_OPEN),
161		    ofl->ofl_name, strerror(err));
162		return (S_ERROR);
163	}
164
165	return (1);
166}
167
168
169/*
170 * If we are creating a memory model we need to update the present memory image.
171 * First we need to call elf_update(ELF_C_NULL) which will calculate the offsets
172 * of each section and its associated data buffers.  From this information we
173 * can then determine what padding is required.
174 * Two actions are necessary to convert the present disc image into a memory
175 * image:
176 *
177 *  o	Loadable segments must be padded so that the next segments virtual
178 *	address and file offset are the same.
179 *
180 *  o	NOBITS sections must be converted into allocated, null filled sections.
181 */
182static uintptr_t
183pad_outfile(Ofl_desc *ofl)
184{
185	Aliste		idx1;
186	off_t		offset;
187	Elf_Scn		*oscn = 0;
188	Sg_desc		*sgp;
189	Ehdr		*ehdr;
190
191	/*
192	 * Update all the elf structures.  This will assign offsets to the
193	 * section headers and data buffers as they relate to the new image.
194	 */
195	if (elf_update(ofl->ofl_welf, ELF_C_NULL) == -1) {
196		eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_UPDATE),
197		    ofl->ofl_name);
198		return (S_ERROR);
199	}
200	if ((ehdr = elf_getehdr(ofl->ofl_welf)) == NULL) {
201		eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_GETEHDR),
202		    ofl->ofl_name);
203		return (S_ERROR);
204	}
205
206	/*
207	 * Initialize the offset by skipping the Elf header and program
208	 * headers.
209	 */
210	offset = ehdr->e_phoff + (ehdr->e_phnum * ehdr->e_phentsize);
211
212	/*
213	 * Traverse the segment list looking for loadable segments.
214	 */
215	for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) {
216		Phdr	*phdr = &(sgp->sg_phdr);
217		Os_desc	*osp;
218		Aliste	idx2;
219
220		/*
221		 * If we've already processed a loadable segment, the `scn'
222		 * variable will be initialized to the last section that was
223		 * part of that segment.  Add sufficient padding to this section
224		 * to cause the next segments virtual address and file offset to
225		 * be the same.
226		 */
227		if (oscn && (phdr->p_type == PT_LOAD)) {
228			Elf_Data *	data;
229			size_t 		size;
230
231			size = (size_t)(S_ROUND(offset, phdr->p_align) -
232			    offset);
233
234			if ((data = elf_newdata(oscn)) == NULL) {
235				eprintf(ofl->ofl_lml, ERR_ELF,
236				    MSG_INTL(MSG_ELF_NEWDATA), ofl->ofl_name);
237				return (S_ERROR);
238			}
239			if ((data->d_buf = libld_calloc(size, 1)) == 0)
240				return (S_ERROR);
241
242			data->d_type = ELF_T_BYTE;
243			data->d_size = size;
244			data->d_align = 1;
245			data->d_version = ofl->ofl_dehdr->e_version;
246		}
247
248		/*
249		 * Traverse the output sections for this segment calculating the
250		 * offset of each section. Retain the final section descriptor
251		 * as this will be where any padding buffer will be added.
252		 */
253		for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) {
254			Shdr	*shdr = osp->os_shdr;
255
256			offset = (off_t)S_ROUND(offset, shdr->sh_addralign);
257			offset += shdr->sh_size;
258
259			/*
260			 * If this is a NOBITS output section convert all of
261			 * its associated input sections into real, null filled,
262			 * data buffers, and change the section to PROGBITS.
263			 */
264			if (shdr->sh_type == SHT_NOBITS)
265				shdr->sh_type = SHT_PROGBITS;
266		}
267
268		/*
269		 * If this is a loadable segment retain the last output section
270		 * descriptor.  This acts both as a flag that a loadable
271		 * segment has been seen, and as the segment to which a padding
272		 * buffer will be added.
273		 */
274		if (phdr->p_type == PT_LOAD)
275			oscn = osp->os_scn;
276	}
277	return (1);
278}
279
280/*
281 * Create an output section.  The first instance of an input section triggers
282 * the creation of a new output section.
283 */
284static uintptr_t
285create_outsec(Ofl_desc *ofl, Sg_desc *sgp, Os_desc *osp, Word ptype, int shidx,
286    Boolean fixalign)
287{
288	Elf_Scn	*scn;
289	Shdr	*shdr;
290
291	/*
292	 * Get a section descriptor for the section.
293	 */
294	if ((scn = elf_newscn(ofl->ofl_welf)) == NULL) {
295		eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_NEWSCN),
296		    ofl->ofl_name);
297		return (S_ERROR);
298	}
299	osp->os_scn = scn;
300
301	/*
302	 * Get a new section header table entry and copy the pertinent
303	 * information from the in-core descriptor.
304	 */
305	if ((shdr = elf_getshdr(scn)) == NULL) {
306		eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_GETSHDR),
307		    ofl->ofl_name);
308		return (S_ERROR);
309	}
310	*shdr = *(osp->os_shdr);
311	osp->os_shdr = shdr;
312
313	/*
314	 * If this is the first section within a loadable segment, and the
315	 * alignment needs to be updated, record this section.
316	 */
317	if ((fixalign == TRUE) && (ptype == PT_LOAD) && (shidx == 1))
318		sgp->sg_fscn = scn;
319
320	/*
321	 * If not building a relocatable object, remove any of the
322	 * following flags, as they have been acted upon and are not
323	 * meaningful in the output:
324	 *	SHF_ORDERED, SHF_LINK_ORDER, SHF_GROUP
325	 * For relocatable objects, we allow them to propagate to
326	 * the output object to be handled by the next linker that
327	 * sees them.
328	 */
329	if ((ofl->ofl_flags & FLG_OF_RELOBJ) == 0)
330		osp->os_shdr->sh_flags &= ~(ALL_SHF_ORDER|SHF_GROUP);
331
332	/*
333	 * If this is a TLS section, save it so that the PT_TLS program header
334	 * information can be established after the output image has been
335	 * initially created.  At this point, all TLS input sections are ordered
336	 * as they will appear in the output image.
337	 */
338	if ((ofl->ofl_flags & FLG_OF_TLSPHDR) &&
339	    (osp->os_shdr->sh_flags & SHF_TLS) &&
340	    (aplist_append(&ofl->ofl_ostlsseg, osp,
341	    AL_CNT_OFL_OSTLSSEG) == NULL))
342		return (S_ERROR);
343
344	return (0);
345}
346
347/*
348 * Create the elf structures that allow the input data to be associated with the
349 * new image:
350 *
351 *	o	define the new elf image using elf_begin(),
352 *
353 *	o	obtain an elf header for the image,
354 *
355 *	o	traverse the input segments and create a program header array
356 *		to define the required segments,
357 *
358 *	o 	traverse the output sections for each segment assigning a new
359 *		section descriptor and section header for each,
360 *
361 *	o	traverse the input sections associated with each output section
362 *		and assign a new data descriptor to each (each output section
363 *		becomes a linked list of input data buffers).
364 */
365uintptr_t
366ld_create_outfile(Ofl_desc *ofl)
367{
368	Sg_desc		*sgp;
369	Os_desc		*osp;
370	Is_desc		*isp;
371	Elf_Data	*tlsdata = 0;
372	Aliste		idx1;
373	ofl_flag_t	flags = ofl->ofl_flags;
374	ofl_flag_t	flags1 = ofl->ofl_flags1;
375	size_t		ndx;
376	Elf_Cmd		cmd;
377	Boolean		fixalign = FALSE;
378	int		fd, nseg = 0, shidx, dataidx, ptloadidx = 0;
379
380	/*
381	 * If DF_1_NOHDR was set in map_parse() or FLG_OF1_VADDR was set,
382	 * we need to do alignment adjustment.
383	 */
384	if ((flags1 & FLG_OF1_VADDR) ||
385	    (ofl->ofl_dtflags_1 & DF_1_NOHDR)) {
386		fixalign = TRUE;
387	}
388
389	if (flags1 & FLG_OF1_MEMORY) {
390		cmd = ELF_C_IMAGE;
391		fd = 0;
392	} else {
393		fd = ofl->ofl_fd;
394		cmd = ELF_C_WRITE;
395	}
396
397	/*
398	 * If there are any ordered sections, handle them here.
399	 */
400	if ((ofl->ofl_ordered != NULL) &&
401	    (ld_sort_ordered(ofl) == S_ERROR))
402		return (S_ERROR);
403
404	/*
405	 * Tell the access library about our new temporary file.
406	 */
407	if ((ofl->ofl_welf = elf_begin(fd, cmd, 0)) == NULL) {
408		eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_BEGIN),
409		    ofl->ofl_name);
410		return (S_ERROR);
411	}
412
413	/*
414	 * Obtain a new Elf header.
415	 */
416	if ((ofl->ofl_nehdr = elf_newehdr(ofl->ofl_welf)) == NULL) {
417		eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_NEWEHDR),
418		    ofl->ofl_name);
419		return (S_ERROR);
420	}
421	ofl->ofl_nehdr->e_machine = ofl->ofl_dehdr->e_machine;
422
423	DBG_CALL(Dbg_util_nl(ofl->ofl_lml, DBG_NL_STD));
424	for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) {
425		int	frst = 0;
426		Phdr	*phdr = &(sgp->sg_phdr);
427		Word	ptype = phdr->p_type;
428		Aliste	idx2;
429
430		/*
431		 * Count the number of segments that will go in the program
432		 * header table. If a segment is empty, ignore it.
433		 */
434		if (!(flags & FLG_OF_RELOBJ)) {
435			/*
436			 * If the program header type belongs to the os range,
437			 * the resulting object is ELFOSABI_SOLARIS.
438			 */
439			if ((ptype >= PT_LOOS) && (ptype <= PT_HIOS))
440				ofl->ofl_flags |= FLG_OF_OSABI;
441
442			if (ptype == PT_PHDR) {
443				/*
444				 * If we are generating an interp section (and
445				 * thus an associated PT_INTERP program header
446				 * entry) also generate a PT_PHDR program header
447				 * entry.  This allows the kernel to generate
448				 * the appropriate aux vector entries to pass to
449				 * the interpreter (refer to exec/elf/elf.c).
450				 * Note that if an image was generated with an
451				 * interp section, but no associated PT_PHDR
452				 * program header entry, the kernel will simply
453				 * pass the interpreter an open file descriptor
454				 * when the image is executed).
455				 */
456				if (ofl->ofl_osinterp)
457					nseg++;
458			} else if (ptype == PT_INTERP) {
459				if (ofl->ofl_osinterp)
460					nseg++;
461			} else if (ptype == PT_DYNAMIC) {
462				if (flags & FLG_OF_DYNAMIC)
463					nseg++;
464			} else if (ptype == PT_TLS) {
465				if (flags & FLG_OF_TLSPHDR)
466					nseg++;
467			} else if (ptype == PT_SUNW_UNWIND) {
468				if (ofl->ofl_unwindhdr)
469					nseg++;
470			} else if (ptype == PT_SUNWDTRACE) {
471				if (ofl->ofl_dtracesym)
472					nseg++;
473			} else if (ptype == PT_SUNWCAP) {
474				if (ofl->ofl_oscap)
475					nseg++;
476			} else if (sgp->sg_flags & FLG_SG_EMPTY) {
477					nseg++;
478			} else if (sgp->sg_osdescs != NULL) {
479				if ((sgp->sg_flags & FLG_SG_PHREQ) == 0) {
480					/*
481					 * If this is a segment for which
482					 * we are not making a program header,
483					 * don't increment nseg
484					 */
485					ptype = (sgp->sg_phdr).p_type = PT_NULL;
486				} else if (ptype != PT_NULL)
487					nseg++;
488			}
489		}
490
491		/*
492		 * Establish any processing unique to the first loadable
493		 * segment.
494		 */
495		if ((ptype == PT_LOAD) && (ptloadidx == 0)) {
496			ptloadidx++;
497
498			/*
499			 * If the first loadable segment has the ?N flag then
500			 * alignments of following segments need to be fixed,
501			 * plus a .dynamic FLAGS1 setting is required.
502			 */
503			if (sgp->sg_flags & FLG_SG_NOHDR) {
504				fixalign = TRUE;
505				ofl->ofl_dtflags_1 |= DF_1_NOHDR;
506			}
507		}
508
509		shidx = 0;
510		for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) {
511			Aliste	idx3;
512
513			dataidx = 0;
514			for (APLIST_TRAVERSE(osp->os_isdescs, idx3, isp)) {
515				Elf_Data	*data;
516				Ifl_desc	*ifl = isp->is_file;
517
518				/*
519				 * An input section in the list that has
520				 * been previously marked to be discarded
521				 * should be completely ignored.
522				 */
523				if (isp->is_flags & FLG_IS_DISCARD)
524					continue;
525
526				/*
527				 * At this point we know whether a section has
528				 * been referenced.  If it hasn't, and the whole
529				 * file hasn't been referenced (which would have
530				 * been caught in ignore_section_processing()),
531				 * give a diagnostic (-D unused,detail) or
532				 * discard the section if -zignore is in effect.
533				 */
534				if (ifl &&
535				    (((ifl->ifl_flags & FLG_IF_FILEREF) == 0) ||
536				    ((ptype == PT_LOAD) &&
537				    ((isp->is_flags & FLG_IS_SECTREF) == 0) &&
538				    (isp->is_shdr->sh_size > 0)))) {
539					Lm_list	*lml = ofl->ofl_lml;
540
541					if (ifl->ifl_flags & FLG_IF_IGNORE) {
542						isp->is_flags |= FLG_IS_DISCARD;
543						DBG_CALL(Dbg_unused_sec(lml,
544						    isp));
545						continue;
546					} else {
547						DBG_CALL(Dbg_unused_sec(lml,
548						    isp));
549					}
550				}
551
552				/*
553				 * If this section provides no data, and isn't
554				 * referenced, then it can be discarded as well.
555				 * Note, if this is the first input section
556				 * associated to an output section, let it
557				 * through, there may be a legitimate reason why
558				 * the user wants a null section.  Discarding
559				 * additional sections is intended to remove the
560				 * empty clutter the compilers have a habit of
561				 * creating.  Don't provide an unused diagnostic
562				 * as these sections aren't typically the users
563				 * creation.
564				 */
565				if (ifl && dataidx &&
566				    ((isp->is_flags & FLG_IS_SECTREF) == 0) &&
567				    (isp->is_shdr->sh_size == 0)) {
568					isp->is_flags |= FLG_IS_DISCARD;
569					continue;
570				}
571
572				/*
573				 * The first input section triggers the creation
574				 * of the associated output section.
575				 */
576				if (osp->os_scn == NULL) {
577					shidx++;
578
579					if (create_outsec(ofl, sgp, osp, ptype,
580					    shidx, fixalign) == S_ERROR)
581						return (S_ERROR);
582				}
583
584				dataidx++;
585
586				/*
587				 * Create a new output data buffer for each
588				 * input data buffer, thus linking the new
589				 * buffers to the new elf output structures.
590				 * Simply make the new data buffers point to
591				 * the old data.
592				 */
593				if ((data = elf_newdata(osp->os_scn)) == NULL) {
594					eprintf(ofl->ofl_lml, ERR_ELF,
595					    MSG_INTL(MSG_ELF_NEWDATA),
596					    ofl->ofl_name);
597					return (S_ERROR);
598				}
599				*data = *(isp->is_indata);
600				isp->is_indata = data;
601
602				if ((fixalign == TRUE) && (ptype == PT_LOAD) &&
603				    (shidx == 1) && (dataidx == 1))
604					data->d_align = sgp->sg_addralign;
605
606				/*
607				 * Save the first TLS data buffer, as this is
608				 * the start of the TLS segment. Realign this
609				 * buffer based on the alignment requirements
610				 * of all the TLS input sections.
611				 */
612				if ((flags & FLG_OF_TLSPHDR) &&
613				    (isp->is_shdr->sh_flags & SHF_TLS)) {
614					if (tlsdata == 0)
615						tlsdata = data;
616					tlsdata->d_align =
617					    ld_lcm(tlsdata->d_align,
618					    isp->is_shdr->sh_addralign);
619				}
620
621#if	defined(_ELF64) && defined(_ILP32)
622				/*
623				 * 4106312, the 32-bit ELF64 version of ld
624				 * needs to be able to create large .bss
625				 * sections.  The d_size member of Elf_Data
626				 * only allows 32-bits in _ILP32, so we build
627				 * multiple data-items that each fit into 32-
628				 * bits.  libelf (4106398) can summ these up
629				 * into a 64-bit quantity.  This only works
630				 * for NOBITS sections which don't have any
631				 * real data to maintain and don't require
632				 * large file support.
633				 */
634				if (isp->is_shdr->sh_type == SHT_NOBITS) {
635					Xword sz = isp->is_shdr->sh_size;
636
637					while (sz >> 32) {
638						data->d_size = SIZE_MAX;
639						sz -= (Xword)SIZE_MAX;
640
641						data = elf_newdata(osp->os_scn);
642						if (data == NULL)
643							return (S_ERROR);
644					}
645					data->d_size = (size_t)sz;
646				}
647#endif
648
649				/*
650				 * If this segment requires rounding realign the
651				 * first data buffer associated with the first
652				 * section.
653				 */
654				if ((frst++ == 0) &&
655				    (sgp->sg_flags & FLG_SG_ROUND)) {
656					Xword    align;
657
658					if (data->d_align)
659						align = (Xword)
660						    S_ROUND(data->d_align,
661						    sgp->sg_round);
662					else
663						align = sgp->sg_round;
664
665					data->d_align = (size_t)align;
666				}
667			}
668
669			/*
670			 * Clear the szoutrels counter so that it can be used
671			 * again in the building of relocs.  See machrel.c.
672			 */
673			osp->os_szoutrels = 0;
674		}
675	}
676
677	/*
678	 * Did we use ELF features from the osabi range? If so,
679	 * update the ELF header osabi fields. If this doesn't happen,
680	 * those fields remain 0, reflecting a generic System V ELF ABI.
681	 */
682	if (ofl->ofl_flags & FLG_OF_OSABI) {
683		ofl->ofl_nehdr->e_ident[EI_OSABI] = ELFOSABI_SOLARIS;
684		ofl->ofl_nehdr->e_ident[EI_ABIVERSION] = EAV_SUNW_CURRENT;
685	}
686
687	/*
688	 * Build an empty PHDR.
689	 */
690	if (nseg) {
691		if ((ofl->ofl_phdr = elf_newphdr(ofl->ofl_welf,
692		    nseg)) == NULL) {
693			eprintf(ofl->ofl_lml, ERR_ELF,
694			    MSG_INTL(MSG_ELF_NEWPHDR), ofl->ofl_name);
695			return (S_ERROR);
696		}
697	}
698
699	/*
700	 * If we need to generate a memory model, pad the image.
701	 */
702	if (flags1 & FLG_OF1_MEMORY) {
703		if (pad_outfile(ofl) == S_ERROR)
704			return (S_ERROR);
705	}
706
707	/*
708	 * After all the basic input file processing, all data pointers are
709	 * referencing two types of memory:
710	 *
711	 *	o	allocated memory, ie. elf structures, internal link
712	 *		editor structures, and any new sections that have been
713	 *		created.
714	 *
715	 *	o	original input file mmap'ed memory, ie. the actual data
716	 *		sections of the input file images.
717	 *
718	 * Up until now, the only memory modifications have been carried out on
719	 * the allocated memory.  Before carrying out any relocations, write the
720	 * new output file image and reassign any necessary data pointers to the
721	 * output files memory image.  This insures that any relocation
722	 * modifications are made to the output file image and not to the input
723	 * file image, thus preventing the creation of dirty pages and reducing
724	 * the overall swap space requirement.
725	 *
726	 * Write out the elf structure so as to create the new file image.
727	 */
728	if ((ofl->ofl_size = (size_t)elf_update(ofl->ofl_welf,
729	    ELF_C_WRIMAGE)) == (size_t)-1) {
730		eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_UPDATE),
731		    ofl->ofl_name);
732		return (S_ERROR);
733	}
734
735	/*
736	 * Initialize the true `ofl' information with the memory images address
737	 * and size.  This will be used to write() out the image once any
738	 * relocation processing has been completed.  We also use this image
739	 * information to setup a new Elf descriptor, which is used to obtain
740	 * all the necessary elf pointers within the new output image.
741	 */
742	if ((ofl->ofl_elf = elf_begin(0, ELF_C_IMAGE,
743	    ofl->ofl_welf)) == NULL) {
744		eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_BEGIN),
745		    ofl->ofl_name);
746		return (S_ERROR);
747	}
748	if ((ofl->ofl_nehdr = elf_getehdr(ofl->ofl_elf)) == NULL) {
749		eprintf(ofl->ofl_lml, ERR_ELF, MSG_INTL(MSG_ELF_GETEHDR),
750		    ofl->ofl_name);
751		return (S_ERROR);
752	}
753	if (!(flags & FLG_OF_RELOBJ))
754		if ((ofl->ofl_phdr = elf_getphdr(ofl->ofl_elf)) == NULL) {
755			eprintf(ofl->ofl_lml, ERR_ELF,
756			    MSG_INTL(MSG_ELF_GETPHDR), ofl->ofl_name);
757			return (S_ERROR);
758		}
759
760	/*
761	 * Reinitialize the section descriptors, section headers and obtain new
762	 * output data buffer pointers (these will be used to perform any
763	 * relocations).
764	 */
765	ndx = 0;
766	for (APLIST_TRAVERSE(ofl->ofl_segs, idx1, sgp)) {
767		Phdr	*_phdr = &(sgp->sg_phdr);
768		Os_desc	*osp;
769		Aliste	idx2;
770		Boolean	recorded = FALSE;
771
772		for (APLIST_TRAVERSE(sgp->sg_osdescs, idx2, osp)) {
773			/*
774			 * Make sure that an output section was originally
775			 * created.  Input sections that had been marked as
776			 * discarded may have made an output section
777			 * unnecessary.  Remove this alist entry so that
778			 * future output section descriptor processing doesn't
779			 * have to compensate for this empty section.
780			 */
781			if (osp->os_scn == NULL) {
782				aplist_delete(sgp->sg_osdescs, &idx2);
783				continue;
784			}
785			if ((osp->os_scn =
786			    elf_getscn(ofl->ofl_elf, ++ndx)) == NULL) {
787				eprintf(ofl->ofl_lml, ERR_ELF,
788				    MSG_INTL(MSG_ELF_GETSCN), ofl->ofl_name,
789				    ndx);
790				return (S_ERROR);
791			}
792			if ((osp->os_shdr =
793			    elf_getshdr(osp->os_scn)) == NULL) {
794				eprintf(ofl->ofl_lml, ERR_ELF,
795				    MSG_INTL(MSG_ELF_GETSHDR), ofl->ofl_name);
796				return (S_ERROR);
797			}
798			if ((fixalign == TRUE) && sgp->sg_fscn &&
799			    (recorded == FALSE)) {
800				size_t	fndx;
801				Elf_Scn *scn;
802
803				scn = sgp->sg_fscn;
804				if ((fndx = elf_ndxscn(scn)) == SHN_UNDEF) {
805					eprintf(ofl->ofl_lml, ERR_ELF,
806					    MSG_INTL(MSG_ELF_NDXSCN),
807					    ofl->ofl_name);
808					return (S_ERROR);
809				}
810				if (ndx == fndx) {
811					sgp->sg_fscn = osp->os_scn;
812					recorded = TRUE;
813				}
814			}
815
816			if ((osp->os_outdata =
817			    elf_getdata(osp->os_scn, NULL)) == NULL) {
818				eprintf(ofl->ofl_lml, ERR_ELF,
819				    MSG_INTL(MSG_ELF_GETDATA), ofl->ofl_name);
820				return (S_ERROR);
821			}
822
823			/*
824			 * If this section is part of a loadable segment insure
825			 * that the segments alignment is appropriate.
826			 */
827			if (_phdr->p_type == PT_LOAD) {
828				_phdr->p_align = ld_lcm(_phdr->p_align,
829				    osp->os_shdr->sh_addralign);
830			}
831		}
832	}
833	return (1);
834}
835