elf2ecoff.c revision 1.19
1/*	$NetBSD: elf2ecoff.c,v 1.19 2002/03/24 19:19:29 bouyer Exp $	*/
2
3/*
4 * Copyright (c) 1997 Jonathan Stone
5 *    All rights reserved.
6 * Copyright (c) 1995
7 *	Ted Lemon (hereinafter referred to as the author)
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. The name of the author may not be used to endorse or promote products
18 *    derived from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33/* elf2ecoff.c
34
35   This program converts an elf executable to an ECOFF executable.
36   No symbol table is retained.   This is useful primarily in building
37   net-bootable kernels for machines (e.g., DECstation and Alpha) which
38   only support the ECOFF object file format. */
39
40#include <sys/types.h>
41#include <err.h>
42#include <errno.h>
43#include <fcntl.h>
44#include <unistd.h>
45#include <sys/exec_elf.h>
46#include <stdio.h>
47#include <sys/exec_ecoff.h>
48#include <stdlib.h>
49#include <string.h>
50#include <limits.h>
51
52#ifdef HAVE_CONFIG_H
53#include <config.h>
54#endif
55
56
57#define	ISLAST(p)	(p->n_un.n_name == 0 || p->n_un.n_name[0] == 0)
58
59struct sect {
60	unsigned long vaddr;
61	unsigned long len;
62};
63
64struct elf_syms {
65	int     nsymbols;
66	Elf32_Sym *elf_syms;
67	off_t   stringsize;
68	char   *stringtab;
69};
70
71struct ecoff_syms {
72	int     nsymbols;
73	struct ecoff_extsym *ecoff_syms;
74	off_t   stringsize;
75	char   *stringtab;
76};
77
78int     debug = 0;
79
80int     phcmp(Elf32_Phdr * h1, Elf32_Phdr * h2);
81
82
83char   *saveRead(int file, off_t offset, off_t len, char *name);
84void    safewrite(int outfile, void *buf, off_t len, const char *msg);
85void    copy(int, int, off_t, off_t);
86void    combine(struct sect * base, struct sect * new, int paddable);
87void    translate_syms(struct elf_syms *, struct ecoff_syms *);
88void
89elf_symbol_table_to_ecoff(int out, int in,
90    struct ecoff_exechdr * ep,
91    off_t symoff, off_t symsize,
92    off_t stroff, off_t strsize);
93
94
95int
96make_ecoff_section_hdrs(struct ecoff_exechdr * ep,
97    struct ecoff_scnhdr * esecs);
98
99void
100write_ecoff_symhdr(int outfile, struct ecoff_exechdr * ep,
101    struct ecoff_symhdr * symhdrp,
102    long nesyms, long extsymoff, long extstroff,
103    long strsize);
104
105void    pad16(int fd, int size, const char *msg);
106void	bswap32_region(u_int32_t* , int);
107
108int    *symTypeTable;
109int	needswap;
110
111
112
113
114void
115elf_read_syms(struct elf_syms * elfsymsp, int infile,
116    off_t symoff, off_t symsize, off_t stroff, off_t strsize);
117
118
119int
120main(int argc, char **argv, char **envp)
121{
122	Elf32_Ehdr ex;
123	Elf32_Phdr *ph;
124	Elf32_Shdr *sh;
125	char   *shstrtab;
126	int     strtabix, symtabix;
127	int     i, pad;
128	struct sect text, data, bss;	/* a.out-compatible sections */
129	struct sect rdata, sdata, sbss;	/* ECOFF-only sections */
130
131	struct ecoff_exechdr ep;
132	struct ecoff_scnhdr esecs[6];
133	struct ecoff_symhdr symhdr;
134
135	int     infile, outfile;
136	unsigned long cur_vma = ULONG_MAX;
137	int     symflag = 0;
138	int     nsecs = 0;
139	int	mipsel;
140
141
142	text.len = data.len = bss.len = 0;
143	text.vaddr = data.vaddr = bss.vaddr = 0;
144
145	rdata.len = sdata.len = sbss.len = 0;
146	rdata.vaddr = sdata.vaddr = sbss.vaddr = 0;
147
148	/* Check args... */
149	if (argc < 3 || argc > 4) {
150usage:
151		fprintf(stderr,
152		    "usage: elf2ecoff <elf executable> <ECOFF executable> [-s]\n");
153		exit(1);
154	}
155	if (argc == 4) {
156		if (strcmp(argv[3], "-s"))
157			goto usage;
158		symflag = 1;
159	}
160	/* Try the input file... */
161	if ((infile = open(argv[1], O_RDONLY)) < 0) {
162		fprintf(stderr, "Can't open %s for read: %s\n",
163		    argv[1], strerror(errno));
164		exit(1);
165	}
166	/* Read the header, which is at the beginning of the file... */
167	i = read(infile, &ex, sizeof ex);
168	if (i != sizeof ex) {
169		fprintf(stderr, "ex: %s: %s.\n",
170		    argv[1], i ? strerror(errno) : "End of file reached");
171		exit(1);
172	}
173	if (ex.e_ident[EI_DATA] == ELFDATA2LSB)
174		mipsel = 1;
175	else if (ex.e_ident[EI_DATA] == ELFDATA2MSB)
176		mipsel = 0;
177	else {
178		fprintf(stderr, "invalid ELF byte order %d\n",
179		    ex.e_ident[EI_DATA]);
180		exit(1);
181	}
182#if BYTE_ORDER == BIG_ENDIAN
183	if (mipsel)
184		needswap = 1;
185	else
186		needswap = 0;
187#elif BYTE_ORDER == LITTLE_ENDIAN
188	if (mipsel)
189		needswap = 0;
190	else
191		needswap = 1;
192#else
193#error "unknown endian"
194#endif
195
196	if (needswap) {
197		ex.e_type	= bswap16(ex.e_type);
198		ex.e_machine	= bswap16(ex.e_machine);
199		ex.e_version	= bswap32(ex.e_version);
200		ex.e_entry 	= bswap32(ex.e_entry);
201		ex.e_phoff	= bswap32(ex.e_phoff);
202		ex.e_shoff	= bswap32(ex.e_shoff);
203		ex.e_flags	= bswap32(ex.e_flags);
204		ex.e_ehsize	= bswap16(ex.e_ehsize);
205		ex.e_phentsize	= bswap16(ex.e_phentsize);
206		ex.e_phnum	= bswap16(ex.e_phnum);
207		ex.e_shentsize	= bswap16(ex.e_shentsize);
208		ex.e_shnum	= bswap16(ex.e_shnum);
209		ex.e_shstrndx	= bswap16(ex.e_shstrndx);
210	}
211
212	/* Read the program headers... */
213	ph = (Elf32_Phdr *) saveRead(infile, ex.e_phoff,
214	    ex.e_phnum * sizeof(Elf32_Phdr), "ph");
215	if (needswap)
216		bswap32_region((u_int32_t*)ph, sizeof(Elf32_Phdr) * ex.e_phnum);
217	/* Read the section headers... */
218	sh = (Elf32_Shdr *) saveRead(infile, ex.e_shoff,
219	    ex.e_shnum * sizeof(Elf32_Shdr), "sh");
220	if (needswap)
221		bswap32_region((u_int32_t*)sh, sizeof(Elf32_Shdr) * ex.e_shnum);
222
223	/* Read in the section string table. */
224	shstrtab = saveRead(infile, sh[ex.e_shstrndx].sh_offset,
225	    sh[ex.e_shstrndx].sh_size, "shstrtab");
226
227
228	/* Look for the symbol table and string table... Also map section
229	 * indices to symbol types for a.out */
230	symtabix = 0;
231	strtabix = 0;
232	for (i = 0; i < ex.e_shnum; i++) {
233		char   *name = shstrtab + sh[i].sh_name;
234		if (!strcmp(name, ".symtab"))
235			symtabix = i;
236		else
237			if (!strcmp(name, ".strtab"))
238				strtabix = i;
239
240	}
241
242	/* Figure out if we can cram the program header into an ECOFF
243	 * header...  Basically, we can't handle anything but loadable
244	 * segments, but we can ignore some kinds of segments.  We can't
245	 * handle holes in the address space.  Segments may be out of order,
246	 * so we sort them first. */
247
248	qsort(ph, ex.e_phnum, sizeof(Elf32_Phdr),
249	    (int (*) (const void *, const void *)) phcmp);
250
251	for (i = 0; i < ex.e_phnum; i++) {
252		/* Section types we can ignore... */
253		if (ph[i].p_type == PT_NULL || ph[i].p_type == PT_NOTE ||
254		    ph[i].p_type == PT_PHDR ||
255		    ph[i].p_type == PT_MIPS_REGINFO) {
256
257			if (debug) {
258				fprintf(stderr, "  skipping PH %d type %d flags 0x%x\n",
259				    i, ph[i].p_type, ph[i].p_flags);
260			}
261			continue;
262		}
263		/* Section types we can't handle... */
264		else
265			if (ph[i].p_type != PT_LOAD) {
266				fprintf(stderr, "Program header %d type %d can't be converted.\n",
267				    i, ph[i].p_type);
268				exit(1);
269			}
270		/* Writable (data) segment? */
271		if (ph[i].p_flags & PF_W) {
272			struct sect ndata, nbss;
273
274			ndata.vaddr = ph[i].p_vaddr;
275			ndata.len = ph[i].p_filesz;
276			nbss.vaddr = ph[i].p_vaddr + ph[i].p_filesz;
277			nbss.len = ph[i].p_memsz - ph[i].p_filesz;
278
279			if (debug) {
280				fprintf(stderr,
281				    "  combinining PH %d type %d flags 0x%x with data, ndata = %ld, nbss =%ld\n", i, ph[i].p_type, ph[i].p_flags, ndata.len, nbss.len);
282			}
283			combine(&data, &ndata, 0);
284			combine(&bss, &nbss, 1);
285		} else {
286			struct sect ntxt;
287
288			ntxt.vaddr = ph[i].p_vaddr;
289			ntxt.len = ph[i].p_filesz;
290			if (debug) {
291
292				fprintf(stderr,
293				    "  combinining PH %d type %d flags 0x%x with text, len = %ld\n",
294				    i, ph[i].p_type, ph[i].p_flags, ntxt.len);
295			}
296			combine(&text, &ntxt, 0);
297		}
298		/* Remember the lowest segment start address. */
299		if (ph[i].p_vaddr < cur_vma)
300			cur_vma = ph[i].p_vaddr;
301	}
302
303	/* Sections must be in order to be converted... */
304	if (text.vaddr > data.vaddr || data.vaddr > bss.vaddr ||
305	    text.vaddr + text.len > data.vaddr || data.vaddr + data.len > bss.vaddr) {
306		fprintf(stderr, "Sections ordering prevents a.out conversion.\n");
307		exit(1);
308	}
309	/* If there's a data section but no text section, then the loader
310	 * combined everything into one section.   That needs to be the text
311	 * section, so just make the data section zero length following text. */
312	if (data.len && !text.len) {
313		text = data;
314		data.vaddr = text.vaddr + text.len;
315		data.len = 0;
316	}
317	/* If there is a gap between text and data, we'll fill it when we copy
318	 * the data, so update the length of the text segment as represented
319	 * in a.out to reflect that, since a.out doesn't allow gaps in the
320	 * program address space. */
321	if (text.vaddr + text.len < data.vaddr)
322		text.len = data.vaddr - text.vaddr;
323
324	/* We now have enough information to cons up an a.out header... */
325	ep.a.magic = ECOFF_OMAGIC;
326	ep.a.vstamp = 2 * 256 + 10;	/* compatible with version 2.10 */
327	ep.a.tsize = text.len;
328	ep.a.dsize = data.len;
329	ep.a.bsize = bss.len;
330	ep.a.entry = ex.e_entry;
331	ep.a.text_start = text.vaddr;
332	ep.a.data_start = data.vaddr;
333	ep.a.bss_start = bss.vaddr;
334	ep.a.gprmask = 0xf3fffffe;
335	memset(&ep.a.cprmask, 0, sizeof ep.a.cprmask);
336	ep.a.gp_value = 0;	/* unused. */
337
338	if (mipsel)
339		ep.f.f_magic = ECOFF_MAGIC_MIPSEL;
340	else
341		ep.f.f_magic = ECOFF_MAGIC_MIPSEB;
342
343	ep.f.f_nscns = 6;
344	ep.f.f_timdat = 0;	/* bogus */
345	ep.f.f_symptr = 0;
346	ep.f.f_nsyms = sizeof(struct ecoff_symhdr);
347	ep.f.f_opthdr = sizeof ep.a;
348	ep.f.f_flags = 0x100f;	/* Stripped, not sharable. */
349
350	memset(esecs, 0, sizeof(esecs));
351
352	/* Make  ECOFF section headers, with empty stubs for
353	 * .rdata/.sdata/.sbss. */
354	make_ecoff_section_hdrs(&ep, esecs);
355
356	nsecs = ep.f.f_nscns;
357
358	if (needswap) {
359		ep.f.f_magic	= bswap16(ep.f.f_magic);
360		ep.f.f_nscns	= bswap16(ep.f.f_nscns);
361		ep.f.f_timdat	= bswap32(ep.f.f_timdat);
362		ep.f.f_symptr	= bswap32(ep.f.f_symptr);
363		ep.f.f_nsyms	= bswap32(ep.f.f_nsyms);
364		ep.f.f_opthdr	= bswap16(ep.f.f_opthdr);
365		ep.f.f_flags	= bswap16(ep.f.f_flags);
366		ep.a.magic	= bswap16(ep.a.magic);
367		ep.a.vstamp	= bswap16(ep.a.vstamp);
368		ep.a.tsize	= bswap32(ep.a.tsize);
369		ep.a.dsize	= bswap32(ep.a.dsize);
370		ep.a.bsize	= bswap32(ep.a.bsize);
371		ep.a.entry	= bswap32(ep.a.entry);
372		ep.a.text_start	= bswap32(ep.a.text_start);
373		ep.a.data_start	= bswap32(ep.a.data_start);
374		ep.a.bss_start	= bswap32(ep.a.bss_start);
375		ep.a.gprmask	= bswap32(ep.a.gprmask);
376		bswap32_region((u_int32_t*)ep.a.cprmask, sizeof(ep.a.cprmask));
377		ep.a.gp_value	= bswap32(ep.a.gp_value);
378		for (i = 0; i < sizeof(esecs) / sizeof(esecs[0]); i++) {
379			esecs[i].s_paddr	= bswap32(esecs[i].s_paddr);
380			esecs[i].s_vaddr	= bswap32(esecs[i].s_vaddr);
381			esecs[i].s_size 	= bswap32(esecs[i].s_size);
382			esecs[i].s_scnptr	= bswap32(esecs[i].s_scnptr);
383			esecs[i].s_relptr	= bswap32(esecs[i].s_relptr);
384			esecs[i].s_lnnoptr	= bswap32(esecs[i].s_lnnoptr);
385			esecs[i].s_nreloc	= bswap16(esecs[i].s_nreloc);
386			esecs[i].s_nlnno	= bswap16(esecs[i].s_nlnno);
387			esecs[i].s_flags	= bswap32(esecs[i].s_flags);
388		}
389	}
390
391	/* Make the output file... */
392	if ((outfile = open(argv[2], O_WRONLY | O_CREAT, 0777)) < 0) {
393		fprintf(stderr, "Unable to create %s: %s\n", argv[2], strerror(errno));
394		exit(1);
395	}
396	/* Truncate file... */
397	if (ftruncate(outfile, 0)) {
398		warn("ftruncate %s", argv[2]);
399	}
400	/* Write the headers... */
401	safewrite(outfile, &ep.f, sizeof(ep.f), "ep.f: write: %s\n");
402	if (debug)
403		fprintf(stderr, "wrote %d byte file header.\n", sizeof(ep.f));
404
405	safewrite(outfile, &ep.a, sizeof(ep.a), "ep.a: write: %s\n");
406	if (debug)
407		fprintf(stderr, "wrote %d byte a.out header.\n", sizeof(ep.a));
408
409	safewrite(outfile, &esecs, sizeof(esecs[0]) * nsecs,
410	    "esecs: write: %s\n");
411	if (debug)
412		fprintf(stderr, "wrote %d bytes of section headers.\n",
413		    sizeof(esecs[0]) * nsecs);
414
415
416	pad = ((sizeof ep.f + sizeof ep.a + sizeof esecs) & 15);
417	if (pad) {
418		pad = 16 - pad;
419		pad16(outfile, pad, "ipad: write: %s\n");
420		if (debug)
421			fprintf(stderr, "wrote %d byte pad.\n", pad);
422	}
423	/* Copy the loadable sections.   Zero-fill any gaps less than 64k;
424	 * complain about any zero-filling, and die if we're asked to
425	 * zero-fill more than 64k. */
426	for (i = 0; i < ex.e_phnum; i++) {
427		/* Unprocessable sections were handled above, so just verify
428		 * that the section can be loaded before copying. */
429		if (ph[i].p_type == PT_LOAD && ph[i].p_filesz) {
430			if (cur_vma != ph[i].p_vaddr) {
431				unsigned long gap = ph[i].p_vaddr - cur_vma;
432				char    obuf[1024];
433				if (gap > 65536) {
434					fprintf(stderr, "Intersegment gap (%ld bytes) too large.\n",
435					    gap);
436					exit(1);
437				}
438				if (debug)
439					fprintf(stderr, "Warning: %ld byte intersegment gap.\n", gap);
440				memset(obuf, 0, sizeof obuf);
441				while (gap) {
442					int     count = write(outfile, obuf, (gap > sizeof obuf
443						? sizeof obuf : gap));
444					if (count < 0) {
445						fprintf(stderr, "Error writing gap: %s\n",
446						    strerror(errno));
447						exit(1);
448					}
449					gap -= count;
450				}
451			}
452			if (debug)
453				fprintf(stderr, "writing %d bytes...\n", ph[i].p_filesz);
454			copy(outfile, infile, ph[i].p_offset, ph[i].p_filesz);
455			cur_vma = ph[i].p_vaddr + ph[i].p_filesz;
456		}
457	}
458
459
460	if (debug)
461		fprintf(stderr, "writing syms at offset 0x%lx\n",
462		    (u_long) ep.f.f_symptr + sizeof(symhdr));
463
464	/* Copy and translate the symbol table... */
465	elf_symbol_table_to_ecoff(outfile, infile, &ep,
466	    sh[symtabix].sh_offset, sh[symtabix].sh_size,
467	    sh[strtabix].sh_offset, sh[strtabix].sh_size);
468
469	/*
470         * Write a page of padding for boot PROMS that read entire pages.
471         * Without this, they may attempt to read past the end of the
472         * data section, incur an error, and refuse to boot.
473         */
474	{
475		char    obuf[4096];
476		memset(obuf, 0, sizeof obuf);
477		if (write(outfile, obuf, sizeof(obuf)) != sizeof(obuf)) {
478			fprintf(stderr, "Error writing PROM padding: %s\n",
479			    strerror(errno));
480			exit(1);
481		}
482	}
483
484	/* Looks like we won... */
485	exit(0);
486}
487
488void
489copy(out, in, offset, size)
490	int     out, in;
491	off_t   offset, size;
492{
493	char    ibuf[4096];
494	int     remaining, cur, count;
495
496	/* Go to the start of the ELF symbol table... */
497	if (lseek(in, offset, SEEK_SET) < 0) {
498		perror("copy: lseek");
499		exit(1);
500	}
501	remaining = size;
502	while (remaining) {
503		cur = remaining;
504		if (cur > sizeof ibuf)
505			cur = sizeof ibuf;
506		remaining -= cur;
507		if ((count = read(in, ibuf, cur)) != cur) {
508			fprintf(stderr, "copy: read: %s\n",
509			    count ? strerror(errno) : "premature end of file");
510			exit(1);
511		}
512		safewrite(out, ibuf, cur, "copy: write: %s\n");
513	}
514}
515/* Combine two segments, which must be contiguous.   If pad is true, it's
516   okay for there to be padding between. */
517void
518combine(base, new, pad)
519	struct sect *base, *new;
520	int     pad;
521{
522	if (!base->len)
523		*base = *new;
524	else
525		if (new->len) {
526			if (base->vaddr + base->len != new->vaddr) {
527				if (pad)
528					base->len = new->vaddr - base->vaddr;
529				else {
530					fprintf(stderr,
531					    "Non-contiguous data can't be converted.\n");
532					exit(1);
533				}
534			}
535			base->len += new->len;
536		}
537}
538
539int
540phcmp(h1, h2)
541	Elf32_Phdr *h1, *h2;
542{
543	if (h1->p_vaddr > h2->p_vaddr)
544		return 1;
545	else
546		if (h1->p_vaddr < h2->p_vaddr)
547			return -1;
548		else
549			return 0;
550}
551
552char
553       *
554saveRead(int file, off_t offset, off_t len, char *name)
555{
556	char   *tmp;
557	int     count;
558	off_t   off;
559	if ((off = lseek(file, offset, SEEK_SET)) < 0) {
560		fprintf(stderr, "%s: fseek: %s\n", name, strerror(errno));
561		exit(1);
562	}
563	if (!(tmp = (char *) malloc(len))) {
564		fprintf(stderr, "%s: Can't allocate %ld bytes.\n", name, (long) len);
565		exit(1);
566	}
567	count = read(file, tmp, len);
568	if (count != len) {
569		fprintf(stderr, "%s: read: %s.\n",
570		    name, count ? strerror(errno) : "End of file reached");
571		exit(1);
572	}
573	return tmp;
574}
575
576void
577safewrite(int outfile, void *buf, off_t len, const char *msg)
578{
579	int     written;
580	written = write(outfile, (char *) buf, len);
581	if (written != len) {
582		fprintf(stderr, msg, strerror(errno));
583		exit(1);
584	}
585}
586
587
588/*
589 * Output only three ECOFF sections, corresponding to ELF psecs
590 * for text, data, and bss.
591 */
592int
593make_ecoff_section_hdrs(ep, esecs)
594	struct ecoff_exechdr *ep;
595	struct ecoff_scnhdr *esecs;
596
597{
598	ep->f.f_nscns = 6;	/* XXX */
599
600	strcpy(esecs[0].s_name, ".text");
601	strcpy(esecs[1].s_name, ".data");
602	strcpy(esecs[2].s_name, ".bss");
603
604	esecs[0].s_paddr = esecs[0].s_vaddr = ep->a.text_start;
605	esecs[1].s_paddr = esecs[1].s_vaddr = ep->a.data_start;
606	esecs[2].s_paddr = esecs[2].s_vaddr = ep->a.bss_start;
607	esecs[0].s_size = ep->a.tsize;
608	esecs[1].s_size = ep->a.dsize;
609	esecs[2].s_size = ep->a.bsize;
610
611	esecs[0].s_scnptr = ECOFF_TXTOFF(ep);
612	esecs[1].s_scnptr = ECOFF_DATOFF(ep);
613#if 0
614	esecs[2].s_scnptr = esecs[1].s_scnptr +
615	    ECOFF_ROUND(esecs[1].s_size, ECOFF_SEGMENT_ALIGNMENT(ep));
616#endif
617
618	esecs[0].s_relptr = esecs[1].s_relptr = esecs[2].s_relptr = 0;
619	esecs[0].s_lnnoptr = esecs[1].s_lnnoptr = esecs[2].s_lnnoptr = 0;
620	esecs[0].s_nreloc = esecs[1].s_nreloc = esecs[2].s_nreloc = 0;
621	esecs[0].s_nlnno = esecs[1].s_nlnno = esecs[2].s_nlnno = 0;
622
623	esecs[1].s_flags = 0x100;	/* ECOFF rdata */
624	esecs[3].s_flags = 0x200;	/* ECOFF sdata */
625	esecs[4].s_flags = 0x400;	/* ECOFF sbss */
626
627	/*
628	 * Set the symbol-table offset  to point at the end of any
629	 * sections we loaded above, so later code can use it to write
630	 * symbol table info..
631	 */
632	ep->f.f_symptr = esecs[1].s_scnptr + esecs[1].s_size;
633	return (ep->f.f_nscns);
634}
635
636
637/*
638 * Write the ECOFF symbol header.
639 * Guess at how big the symbol table will be.
640 * Mark all symbols as EXTERN (for now).
641 */
642void
643write_ecoff_symhdr(out, ep, symhdrp, nesyms, extsymoff, extstroff, strsize)
644	int     out;
645	struct ecoff_exechdr *ep;
646	struct ecoff_symhdr *symhdrp;
647	long    nesyms, extsymoff, extstroff, strsize;
648{
649	if (debug)
650		fprintf(stderr, "writing symhdr for %ld entries at offset 0x%lx\n",
651		    nesyms, (u_long) ep->f.f_symptr);
652
653	ep->f.f_nsyms = sizeof(struct ecoff_symhdr);
654
655	memset(symhdrp, 0, sizeof(*symhdrp));
656	symhdrp->esymMax = nesyms;
657	symhdrp->magic = 0x7009;/* XXX */
658	symhdrp->cbExtOffset = extsymoff;
659	symhdrp->cbSsExtOffset = extstroff;
660
661	symhdrp->issExtMax = strsize;
662	if (debug)
663		fprintf(stderr,
664		    "ECOFF symhdr: symhdr %x, strsize %lx, symsize %lx\n",
665		    sizeof(*symhdrp), strsize,
666		    (nesyms * sizeof(struct ecoff_extsym)));
667
668	if (needswap) {
669		bswap32_region((u_int32_t*)&symhdrp->ilineMax,
670		    sizeof(*symhdrp) -  sizeof(symhdrp->magic) -
671		    sizeof(symhdrp->ilineMax));
672		symhdrp->magic = bswap16(symhdrp->magic);
673		symhdrp->ilineMax = bswap16(symhdrp->ilineMax);
674	}
675
676	safewrite(out, symhdrp, sizeof(*symhdrp),
677	    "writing symbol header: %s\n");
678}
679
680
681void
682elf_read_syms(elfsymsp, in, symoff, symsize, stroff, strsize)
683	struct elf_syms *elfsymsp;
684	int     in;
685	off_t   symoff, symsize;
686	off_t   stroff, strsize;
687{
688	register int nsyms;
689	int i;
690	nsyms = symsize / sizeof(Elf32_Sym);
691
692	/* Suck in the ELF symbol list... */
693	elfsymsp->elf_syms = (Elf32_Sym *)
694	    saveRead(in, symoff, nsyms * sizeof(Elf32_Sym),
695	    "ELF symboltable");
696	elfsymsp->nsymbols = nsyms;
697	if (needswap) {
698		for (i = 0; i < nsyms; i++) {
699			Elf32_Sym *s = &elfsymsp->elf_syms[i];
700			s->st_name	= bswap32(s->st_name);
701			s->st_value	= bswap32(s->st_value);
702			s->st_size	= bswap32(s->st_size);
703			s->st_shndx	= bswap16(s->st_shndx);
704		}
705	}
706
707	/* Suck in the ELF string table... */
708	elfsymsp->stringtab = (char *)
709	    saveRead(in, stroff, strsize, "ELF string table");
710	elfsymsp->stringsize = strsize;
711}
712
713
714/*
715 *
716 */
717void
718elf_symbol_table_to_ecoff(out, in, ep, symoff, symsize, stroff, strsize)
719	int     out, in;
720	struct ecoff_exechdr *ep;
721	off_t   symoff, symsize;
722	off_t   stroff, strsize;
723{
724
725	struct elf_syms elfsymtab;
726	struct ecoff_syms ecoffsymtab;
727	register u_long ecoff_symhdr_off, symtaboff, stringtaboff;
728	register u_long nextoff, symtabsize, ecoff_strsize;
729	int     nsyms, i;
730	struct ecoff_symhdr symhdr;
731	int     padding;
732
733	/* Read in the ELF symbols. */
734	elf_read_syms(&elfsymtab, in, symoff, symsize, stroff, strsize);
735
736	/* Approximate translation to ECOFF. */
737	translate_syms(&elfsymtab, &ecoffsymtab);
738	nsyms = ecoffsymtab.nsymbols;
739
740	/* Compute output ECOFF symbol- and string-table offsets. */
741	ecoff_symhdr_off = ep->f.f_symptr;
742
743	nextoff = ecoff_symhdr_off + sizeof(struct ecoff_symhdr);
744	stringtaboff = nextoff;
745	ecoff_strsize = ECOFF_ROUND(ecoffsymtab.stringsize,
746	    (ECOFF_SEGMENT_ALIGNMENT(ep)));
747
748
749	nextoff = stringtaboff + ecoff_strsize;
750	symtaboff = nextoff;
751	symtabsize = nsyms * sizeof(struct ecoff_extsym);
752	symtabsize = ECOFF_ROUND(symtabsize, ECOFF_SEGMENT_ALIGNMENT(ep));
753
754	/* Write out the symbol header ... */
755	write_ecoff_symhdr(out, ep, &symhdr, nsyms, symtaboff,
756	    stringtaboff, ecoffsymtab.stringsize);
757
758	/* Write out the string table... */
759	padding = ecoff_strsize - ecoffsymtab.stringsize;
760	safewrite(out, ecoffsymtab.stringtab, ecoffsymtab.stringsize,
761	    "string table: write: %s\n");
762	if (padding)
763		pad16(out, padding, "string table: padding: %s\n");
764
765
766	/* Write out the symbol table... */
767	padding = symtabsize - (nsyms * sizeof(struct ecoff_extsym));
768
769	for (i = 0; i < nsyms; i++) {
770		struct ecoff_extsym *es = &ecoffsymtab.ecoff_syms[i];
771		es->es_flags	= bswap16(es->es_flags);
772		es->es_ifd	= bswap16(es->es_ifd);
773		bswap32_region(&es->es_strindex,
774		    sizeof(*es) - sizeof(es->es_flags) - sizeof(es->es_ifd));
775	}
776	safewrite(out, ecoffsymtab.ecoff_syms,
777	    nsyms * sizeof(struct ecoff_extsym),
778	    "symbol table: write: %s\n");
779	if (padding)
780		pad16(out, padding, "symbols: padding: %s\n");
781}
782
783
784
785/*
786 * In-memory translation of ELF symbosl to ECOFF.
787 */
788void
789translate_syms(elfp, ecoffp)
790	struct elf_syms *elfp;
791	struct ecoff_syms *ecoffp;
792{
793
794	int     i;
795	char   *oldstringbase;
796	char   *newstrings, *nsp;
797
798	int     nsyms, idx;
799
800	nsyms = elfp->nsymbols;
801	oldstringbase = elfp->stringtab;
802
803	/* Allocate space for corresponding ECOFF symbols. */
804	memset(ecoffp, 0, sizeof(*ecoffp));
805
806	ecoffp->nsymbols = 0;
807	ecoffp->ecoff_syms = malloc(sizeof(struct ecoff_extsym) * nsyms);
808
809	/* we are going to be no bigger than the ELF symbol table. */
810	ecoffp->stringsize = elfp->stringsize;
811	ecoffp->stringtab = malloc(elfp->stringsize);
812
813	newstrings = (char *) ecoffp->stringtab;
814	nsp = (char *) ecoffp->stringtab;
815	if (!newstrings) {
816		fprintf(stderr, "No memory for new string table!\n");
817		exit(1);
818	}
819	/* Copy and translate  symbols... */
820	idx = 0;
821	for (i = 0; i < nsyms; i++) {
822		int     binding, type;
823
824		binding = ELF32_ST_BIND((elfp->elf_syms[i].st_info));
825		type = ELF32_ST_TYPE((elfp->elf_syms[i].st_info));
826
827		/* skip strange symbols */
828		if (binding == 0) {
829			continue;
830		}
831		/* Copy the symbol into the new table */
832		strcpy(nsp, oldstringbase + elfp->elf_syms[i].st_name);
833		ecoffp->ecoff_syms[idx].es_strindex = nsp - newstrings;
834		nsp += strlen(nsp) + 1;
835
836		/* translate symbol types to ECOFF XXX */
837		ecoffp->ecoff_syms[idx].es_type = 1;
838		ecoffp->ecoff_syms[idx].es_class = 5;
839
840		/* Symbol values in executables should be compatible. */
841		ecoffp->ecoff_syms[idx].es_value = elfp->elf_syms[i].st_value;
842		ecoffp->ecoff_syms[idx].es_symauxindex = 0xfffff;
843
844		idx++;
845	}
846
847	ecoffp->nsymbols = idx;
848	ecoffp->stringsize = nsp - newstrings;
849}
850/*
851 * pad to a 16-byte boundary
852 */
853void
854pad16(int fd, int size, const char *msg)
855{
856	safewrite(fd, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0", size, msg);
857}
858
859/* swap a 32bit region */
860void
861bswap32_region(u_int32_t* p, int len)
862{
863	int i;
864
865	for (i = 0; i < len / sizeof(u_int32_t); i++, p++)
866		*p = bswap32(*p);
867}
868