summaryrefslogtreecommitdiffstats
path: root/arch/mips/boot/elf2ecoff.c
blob: 549c5d6ef6d7c7443634acbdc2a6d8e9c3139aa1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
/*
 * Copyright (c) 1995
 *	Ted Lemon (hereinafter referred to as the author)
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/* elf2ecoff.c

   This program converts an elf executable to an ECOFF executable.
   No symbol table is retained.	  This is useful primarily in building
   net-bootable kernels for machines (e.g., DECstation and Alpha) which
   only support the ECOFF object file format. */

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <elf.h>
#include <limits.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <stdint.h>
#include <inttypes.h>

#include "ecoff.h"

/*
 * Some extra ELF definitions
 */
#define PT_MIPS_REGINFO 	0x70000000	/* Register usage information */
#define PT_MIPS_ABIFLAGS	0x70000003	/* Records ABI related flags  */

/* -------------------------------------------------------------------- */

struct sect {
	uint32_t vaddr;
	uint32_t len;
};

int *symTypeTable;
int must_convert_endian;
int format_bigendian;

static void copy(int out, int in, off_t offset, off_t size)
{
	char ibuf[4096];
	int remaining, cur, count;

	/* Go to the start of the ELF symbol table... */
	if (lseek(in, offset, SEEK_SET) < 0) {
		perror("copy: lseek");
		exit(1);
	}

	remaining = size;
	while (remaining) {
		cur = remaining;
		if (cur > sizeof ibuf)
			cur = sizeof ibuf;
		remaining -= cur;
		if ((count = read(in, ibuf, cur)) != cur) {
			fprintf(stderr, "copy: read: %s\n",
				count ? strerror(errno) :
				"premature end of file");
			exit(1);
		}
		if ((count = write(out, ibuf, cur)) != cur) {
			perror("copy: write");
			exit(1);
		}
	}
}

/*
 * Combine two segments, which must be contiguous.   If pad is true, it's
 * okay for there to be padding between.
 */
static void combine(struct sect *base, struct sect *new, int pad)
{
	if (!base->len)
		*base = *new;
	else if (new->len) {
		if (base->vaddr + base->len != new->vaddr) {
			if (pad)
				base->len = new->vaddr - base->vaddr;
			else {
				fprintf(stderr,
					"Non-contiguous data can't be converted.\n");
				exit(1);
			}
		}
		base->len += new->len;
	}
}

static int phcmp(const void *v1, const void *v2)
{
	const Elf32_Phdr *h1 = v1;
	const Elf32_Phdr *h2 = v2;

	if (h1->p_vaddr > h2->p_vaddr)
		return 1;
	else if (h1->p_vaddr < h2->p_vaddr)
		return -1;
	else
		return 0;
}

static char *saveRead(int file, off_t offset, off_t len, char *name)
{
	char *tmp;
	int count;
	off_t off;
	if ((off = lseek(file, offset, SEEK_SET)) < 0) {
		fprintf(stderr, "%s: fseek: %s\n", name, strerror(errno));
		exit(1);
	}
	if (!(tmp = (char *) malloc(len))) {
		fprintf(stderr, "%s: Can't allocate %ld bytes.\n", name,
			len);
		exit(1);
	}
	count = read(file, tmp, len);
	if (count != len) {
		fprintf(stderr, "%s: read: %s.\n",
			name,
			count ? strerror(errno) : "End of file reached");
		exit(1);
	}
	return tmp;
}

#define swab16(x) \
	((uint16_t)( \
		(((uint16_t)(x) & (uint16_t)0x00ffU) << 8) | \
		(((uint16_t)(x) & (uint16_t)0xff00U) >> 8) ))

#define swab32(x) \
	((unsigned int)( \
		(((uint32_t)(x) & (uint32_t)0x000000ffUL) << 24) | \
		(((uint32_t)(x) & (uint32_t)0x0000ff00UL) <<  8) | \
		(((uint32_t)(x) & (uint32_t)0x00ff0000UL) >>  8) | \
		(((uint32_t)(x) & (uint32_t)0xff000000UL) >> 24) ))

static void convert_elf_hdr(Elf32_Ehdr * e)
{
	e->e_type = swab16(e->e_type);
	e->e_machine = swab16(e->e_machine);
	e->e_version = swab32(e->e_version);
	e->e_entry = swab32(e->e_entry);
	e->e_phoff = swab32(e->e_phoff);
	e->e_shoff = swab32(e->e_shoff);
	e->e_flags = swab32(e->e_flags);
	e->e_ehsize = swab16(e->e_ehsize);
	e->e_phentsize = swab16(e->e_phentsize);
	e->e_phnum = swab16(e->e_phnum);
	e->e_shentsize = swab16(e->e_shentsize);
	e->e_shnum = swab16(e->e_shnum);
	e->e_shstrndx = swab16(e->e_shstrndx);
}

static void convert_elf_phdrs(Elf32_Phdr * p, int num)
{
	int i;

	for (i = 0; i < num; i++, p++) {
		p->p_type = swab32(p->p_type);
		p->p_offset = swab32(p->p_offset);
		p->p_vaddr = swab32(p->p_vaddr);
		p->p_paddr = swab32(p->p_paddr);
		p->p_filesz = swab32(p->p_filesz);
		p->p_memsz = swab32(p->p_memsz);
		p->p_flags = swab32(p->p_flags);
		p->p_align = swab32(p->p_align);
	}

}

static void convert_elf_shdrs(Elf32_Shdr * s, int num)
{
	int i;

	for (i = 0; i < num; i++, s++) {
		s->sh_name = swab32(s->sh_name);
		s->sh_type = swab32(s->sh_type);
		s->sh_flags = swab32(s->sh_flags);
		s->sh_addr = swab32(s->sh_addr);
		s->sh_offset = swab32(s->sh_offset);
		s->sh_size = swab32(s->sh_size);
		s->sh_link = swab32(s->sh_link);
		s->sh_info = swab32(s->sh_info);
		s->sh_addralign = swab32(s->sh_addralign);
		s->sh_entsize = swab32(s->sh_entsize);
	}
}

static void convert_ecoff_filehdr(struct filehdr *f)
{
	f->f_magic = swab16(f->f_magic);
	f->f_nscns = swab16(f->f_nscns);
	f->f_timdat = swab32(f->f_timdat);
	f->f_symptr = swab32(f->f_symptr);
	f->f_nsyms = swab32(f->f_nsyms);
	f->f_opthdr = swab16(f->f_opthdr);
	f->f_flags = swab16(f->f_flags);
}

static void convert_ecoff_aouthdr(struct aouthdr *a)
{
	a->magic = swab16(a->magic);
	a->vstamp = swab16(a->vstamp);
	a->tsize = swab32(a->tsize);
	a->dsize = swab32(a->dsize);
	a->bsize = swab32(a->bsize);
	a->entry = swab32(a->entry);
	a->text_start = swab32(a->text_start);
	a->data_start = swab32(a->data_start);
	a->bss_start = swab32(a->bss_start);
	a->gprmask = swab32(a->gprmask);
	a->cprmask[0] = swab32(a->cprmask[0]);
	a->cprmask[1] = swab32(a->cprmask[1]);
	a->cprmask[2] = swab32(a->cprmask[2]);
	a->cprmask[3] = swab32(a->cprmask[3]);
	a->gp_value = swab32(a->gp_value);
}

static void convert_ecoff_esecs(struct scnhdr *s, int num)
{
	int i;

	for (i = 0; i < num; i++, s++) {
		s->s_paddr = swab32(s->s_paddr);
		s->s_vaddr = swab32(s->s_vaddr);
		s->s_size = swab32(s->s_size);
		s->s_scnptr = swab32(s->s_scnptr);
		s->s_relptr = swab32(s->s_relptr);
		s->s_lnnoptr = swab32(s->s_lnnoptr);
		s->s_nreloc = swab16(s->s_nreloc);
		s->s_nlnno = swab16(s->s_nlnno);
		s->s_flags = swab32(s->s_flags);
	}
}

int main(int argc, char *argv[])
{
	Elf32_Ehdr ex;
	Elf32_Phdr *ph;
	Elf32_Shdr *sh;
	int i, pad;
	struct sect text, data, bss;
	struct filehdr efh;
	struct aouthdr eah;
	struct scnhdr esecs[6];
	int infile, outfile;
	uint32_t cur_vma = UINT32_MAX;
	int addflag = 0;
	int nosecs;

	text.len = data.len = bss.len = 0;
	text.vaddr = data.vaddr = bss.vaddr = 0;

	/* Check args... */
	if (argc < 3 || argc > 4) {
	      usage:
		fprintf(stderr,
			"usage: elf2ecoff <elf executable> <ecoff executable> [-a]\n");
		exit(1);
	}
	if (argc == 4) {
		if (strcmp(argv[3], "-a"))
			goto usage;
		addflag = 1;
	}

	/* Try the input file... */
	if ((infile = open(argv[1], O_RDONLY)) < 0) {
		fprintf(stderr, "Can't open %s for read: %s\n",
			argv[1], strerror(errno));
		exit(1);
	}

	/* Read the header, which is at the beginning of the file... */
	i = read(infile, &ex, sizeof ex);
	if (i != sizeof ex) {
		fprintf(stderr, "ex: %s: %s.\n",
			argv[1],
			i ? strerror(errno) : "End of file reached");
		exit(1);
	}

	if (ex.e_ident[EI_DATA] == ELFDATA2MSB)
		format_bigendian = 1;

	if (ntohs(0xaa55) == 0xaa55) {
		if (!format_bigendian)
			must_convert_endian = 1;
	} else {
		if (format_bigendian)
			must_convert_endian = 1;
	}
	if (must_convert_endian)
		convert_elf_hdr(&ex);

	/* Read the program headers... */
	ph = (Elf32_Phdr *) saveRead(infile, ex.e_phoff,
				     ex.e_phnum * sizeof(Elf32_Phdr),
				     "ph");
	if (must_convert_endian)
		convert_elf_phdrs(ph, ex.e_phnum);
	/* Read the section headers... */
	sh = (Elf32_Shdr *) saveRead(infile, ex.e_shoff,
				     ex.e_shnum * sizeof(Elf32_Shdr),
				     "sh");
	if (must_convert_endian)
		convert_elf_shdrs(sh, ex.e_shnum);

	/* Figure out if we can cram the program header into an ECOFF
	   header...  Basically, we can't handle anything but loadable
	   segments, but we can ignore some kinds of segments.	We can't
	   handle holes in the address space.  Segments may be out of order,
	   so we sort them first. */

	qsort(ph, ex.e_phnum, sizeof(Elf32_Phdr), phcmp);

	for (i = 0; i < ex.e_phnum; i++) {
		/* Section types we can ignore... */
		switch (ph[i].p_type) {
		case PT_NULL:
		case PT_NOTE:
		case PT_PHDR:
		case PT_MIPS_REGINFO:
		case PT_MIPS_ABIFLAGS:
			continue;

		case PT_LOAD:
			/* Writable (data) segment? */
			if (ph[i].p_flags & PF_W) {
				struct sect ndata, nbss;

				ndata.vaddr = ph[i].p_vaddr;
				ndata.len = ph[i].p_filesz;
				nbss.vaddr = ph[i].p_vaddr + ph[i].p_filesz;
				nbss.len = ph[i].p_memsz - ph[i].p_filesz;

				combine(&data, &ndata, 0);
				combine(&bss, &nbss, 1);
			} else {
				struct sect ntxt;

				ntxt.vaddr = ph[i].p_vaddr;
				ntxt.len = ph[i].p_filesz;

				combine(&text, &ntxt, 0);
			}
			/* Remember the lowest segment start address. */
			if (ph[i].p_vaddr < cur_vma)
				cur_vma = ph[i].p_vaddr;
			break;

		default:
			/* Section types we can't handle... */
			fprintf(stderr,
				"Program header %d type %d can't be converted.\n",
				ex.e_phnum, ph[i].p_type);
			exit(1);
		}
	}

	/* Sections must be in order to be converted... */
	if (text.vaddr > data.vaddr || data.vaddr > bss.vaddr ||
	    text.vaddr + text.len > data.vaddr
	    || data.vaddr + data.len > bss.vaddr) {
		fprintf(stderr,
			"Sections ordering prevents a.out conversion.\n");
		exit(1);
	}

	/* If there's a data section but no text section, then the loader
	   combined everything into one section.   That needs to be the
	   text section, so just make the data section zero length following
	   text. */
	if (data.len && !text.len) {
		text = data;
		data.vaddr = text.vaddr + text.len;
		data.len = 0;
	}

	/* If there is a gap between text and data, we'll fill it when we copy
	   the data, so update the length of the text segment as represented in
	   a.out to reflect that, since a.out doesn't allow gaps in the program
	   address space. */
	if (text.vaddr + text.len < data.vaddr)
		text.len = data.vaddr - text.vaddr;

	/* We now have enough information to cons up an a.out header... */
	eah.magic = OMAGIC;
	eah.vstamp = 200;
	eah.tsize = text.len;
	eah.dsize = data.len;
	eah.bsize = bss.len;
	eah.entry = ex.e_entry;
	eah.text_start = text.vaddr;
	eah.data_start = data.vaddr;
	eah.bss_start = bss.vaddr;
	eah.gprmask = 0xf3fffffe;
	memset(&eah.cprmask, '\0', sizeof eah.cprmask);
	eah.gp_value = 0;	/* unused. */

	if (format_bigendian)
		efh.f_magic = MIPSEBMAGIC;
	else
		efh.f_magic = MIPSELMAGIC;
	if (addflag)
		nosecs = 6;
	else
		nosecs = 3;
	efh.f_nscns = nosecs;
	efh.f_timdat = 0;	/* bogus */
	efh.f_symptr = 0;
	efh.f_nsyms = 0;
	efh.f_opthdr = sizeof eah;
	efh.f_flags = 0x100f;	/* Stripped, not shareable. */

	memset(esecs, 0, sizeof esecs);
	strcpy(esecs[0].s_name, ".text");
	strcpy(esecs[1].s_name, ".data");
	strcpy(esecs[2].s_name, ".bss");
	if (addflag) {
		strcpy(esecs[3].s_name, ".rdata");
		strcpy(esecs[4].s_name, ".sdata");
		strcpy(esecs[5].s_name, ".sbss");
	}
	esecs[0].s_paddr = esecs[0].s_vaddr = eah.text_start;
	esecs[1].s_paddr = esecs[1].s_vaddr = eah.data_start;
	esecs[2].s_paddr = esecs[2].s_vaddr = eah.bss_start;
	if (addflag) {
		esecs[3].s_paddr = esecs[3].s_vaddr = 0;
		esecs[4].s_paddr = esecs[4].s_vaddr = 0;
		esecs[5].s_paddr = esecs[5].s_vaddr = 0;
	}
	esecs[0].s_size = eah.tsize;
	esecs[1].s_size = eah.dsize;
	esecs[2].s_size = eah.bsize;
	if (addflag) {
		esecs[3].s_size = 0;
		esecs[4].s_size = 0;
		esecs[5].s_size = 0;
	}
	esecs[0].s_scnptr = N_TXTOFF(efh, eah);
	esecs[1].s_scnptr = N_DATOFF(efh, eah);
#define ECOFF_SEGMENT_ALIGNMENT(a) 0x10
#define ECOFF_ROUND(s, a) (((s)+(a)-1)&~((a)-1))
	esecs[2].s_scnptr = esecs[1].s_scnptr +
	    ECOFF_ROUND(esecs[1].s_size, ECOFF_SEGMENT_ALIGNMENT(&eah));
	if (addflag) {
		esecs[3].s_scnptr = 0;
		esecs[4].s_scnptr = 0;
		esecs[5].s_scnptr = 0;
	}
	esecs[0].s_relptr = esecs[1].s_relptr = esecs[2].s_relptr = 0;
	esecs[0].s_lnnoptr = esecs[1].s_lnnoptr = esecs[2].s_lnnoptr = 0;
	esecs[0].s_nreloc = esecs[1].s_nreloc = esecs[2].s_nreloc = 0;
	esecs[0].s_nlnno = esecs[1].s_nlnno = esecs[2].s_nlnno = 0;
	if (addflag) {
		esecs[3].s_relptr = esecs[4].s_relptr
		    = esecs[5].s_relptr = 0;
		esecs[3].s_lnnoptr = esecs[4].s_lnnoptr
		    = esecs[5].s_lnnoptr = 0;
		esecs[3].s_nreloc = esecs[4].s_nreloc = esecs[5].s_nreloc =
		    0;
		esecs[3].s_nlnno = esecs[4].s_nlnno = esecs[5].s_nlnno = 0;
	}
	esecs[0].s_flags = 0x20;
	esecs[1].s_flags = 0x40;
	esecs[2].s_flags = 0x82;
	if (addflag) {
		esecs[3].s_flags = 0x100;
		esecs[4].s_flags = 0x200;
		esecs[5].s_flags = 0x400;
	}

	/* Make the output file... */
	if ((outfile = open(argv[2], O_WRONLY | O_CREAT, 0777)) < 0) {
		fprintf(stderr, "Unable to create %s: %s\n", argv[2],
			strerror(errno));
		exit(1);
	}

	if (must_convert_endian)
		convert_ecoff_filehdr(&efh);
	/* Write the headers... */
	i = write(outfile, &efh, sizeof efh);
	if (i != sizeof efh) {
		perror("efh: write");
		exit(1);

		for (i = 0; i < nosecs; i++) {
			printf
			    ("Section %d: %s phys %"PRIx32"  size %"PRIx32"\t file offset %"PRIx32"\n",
			     i, esecs[i].s_name, esecs[i].s_paddr,
			     esecs[i].s_size, esecs[i].s_scnptr);
		}
	}
	fprintf(stderr, "wrote %d byte file header.\n", i);

	if (must_convert_endian)
		convert_ecoff_aouthdr(&eah);
	i = write(outfile, &eah, sizeof eah);
	if (i != sizeof eah) {
		perror("eah: write");
		exit(1);
	}
	fprintf(stderr, "wrote %d byte a.out header.\n", i);

	if (must_convert_endian)
		convert_ecoff_esecs(&esecs[0], nosecs);
	i = write(outfile, &esecs, nosecs * sizeof(struct scnhdr));
	if (i != nosecs * sizeof(struct scnhdr)) {
		perror("esecs: write");
		exit(1);
	}
	fprintf(stderr, "wrote %d bytes of section headers.\n", i);

	pad = (sizeof(efh) + sizeof(eah) + nosecs * sizeof(struct scnhdr)) & 15;
	if (pad) {
		pad = 16 - pad;
		i = write(outfile, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0", pad);
		if (i < 0) {
			perror("ipad: write");
			exit(1);
		}
		fprintf(stderr, "wrote %d byte pad.\n", i);
	}

	/*
	 * Copy the loadable sections.	 Zero-fill any gaps less than 64k;
	 * complain about any zero-filling, and die if we're asked to zero-fill
	 * more than 64k.
	 */
	for (i = 0; i < ex.e_phnum; i++) {
		/* Unprocessable sections were handled above, so just verify that
		   the section can be loaded before copying. */
		if (ph[i].p_type == PT_LOAD && ph[i].p_filesz) {
			if (cur_vma != ph[i].p_vaddr) {
				uint32_t gap = ph[i].p_vaddr - cur_vma;
				char obuf[1024];
				if (gap > 65536) {
					fprintf(stderr,
						"Intersegment gap (%"PRId32" bytes) too large.\n",
						gap);
					exit(1);
				}
				fprintf(stderr,
					"Warning: %d byte intersegment gap.\n",
					gap);
				memset(obuf, 0, sizeof obuf);
				while (gap) {
					int count =
					    write(outfile, obuf,
						  (gap >
						   sizeof obuf ? sizeof
						   obuf : gap));
					if (count < 0) {
						fprintf(stderr,
							"Error writing gap: %s\n",
							strerror(errno));
						exit(1);
					}
					gap -= count;
				}
			}
			fprintf(stderr, "writing %d bytes...\n",
				ph[i].p_filesz);
			copy(outfile, infile, ph[i].p_offset,
			     ph[i].p_filesz);
			cur_vma = ph[i].p_vaddr + ph[i].p_filesz;
		}
	}

	/*
	 * Write a page of padding for boot PROMS that read entire pages.
	 * Without this, they may attempt to read past the end of the
	 * data section, incur an error, and refuse to boot.
	 */
	{
		char obuf[4096];
		memset(obuf, 0, sizeof obuf);
		if (write(outfile, obuf, sizeof(obuf)) != sizeof(obuf)) {
			fprintf(stderr, "Error writing PROM padding: %s\n",
				strerror(errno));
			exit(1);
		}
	}

	/* Looks like we won... */
	exit(0);
}