/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 1992-2003 Sun Microsystems, Inc.
 * All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident	"%Z%%M%	%I%	%E% SMI"

#include <sys/exechdr.h>
#include <sys/elf.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <strings.h>

static Elf32_Ehdr elfhdr;
static Elf32_Phdr phdr, dphdr;
static char machine[] = {0, 0, 3, 0, 2};
static int fd;
static char buf[4096];
static long lalignbuf[2];

int
main(int argc, char **argv)
{
	int ifd;
	struct exec exec;
	int count;
	int tot_write = 0;
	long lalign;
	int lbytes;
	int text_written = 0;
	int data_written = 0;
	char *prog = *argv;

	if (argc < 3) {
		(void) printf("usage: stripalign elf_file a.outfile \n");
		exit(1);
	}
	if ((ifd = open(argv[1], O_RDONLY)) ==  -1) {
		perror("open input");
		exit(1);
	}
	if (read(ifd, &elfhdr, sizeof (elfhdr)) < sizeof (elfhdr)) {
		perror("read elfhdr");
		exit(1);
	}
	if ((fd = open(argv[2], O_RDWR | O_TRUNC | O_CREAT, 0777)) ==  -1) {
		perror("open aout");
		exit(1);
	}

	if (*(int *)(elfhdr.e_ident) != *(int *)(ELFMAG)) {
		perror("elfmag");
		exit(1);
	}
	if (lseek(ifd, elfhdr.e_phoff, 0) == -1) {
		perror("lseek");
		exit(1);
	}
	if (read(ifd, &phdr, sizeof (phdr)) < sizeof (phdr)) {
		perror("read phdr");
		exit(1);
	}
	if (read(ifd, &dphdr, sizeof (dphdr)) < sizeof (dphdr)) {
		perror("read dphdr");
		exit(1);
	}

	bzero(&exec, sizeof (exec));
	exec.a_dynamic = 0;
	exec.a_toolversion = 1;
	exec.a_machtype = machine[elfhdr.e_machine];
	exec.a_magic = OMAGIC;
	exec.a_text = dphdr.p_vaddr - phdr.p_vaddr;
	exec.a_data = dphdr.p_filesz;
	exec.a_bss = dphdr.p_memsz - dphdr.p_filesz;
	exec.a_entry = elfhdr.e_entry;

	if (write(fd, &exec, sizeof (exec)) != sizeof (exec)) {
		perror("write exec");
		exit(1);
	}
	tot_write += sizeof (exec);

	if (lseek(ifd, phdr.p_offset, 0) == -1) {
		perror("lseek text");
		exit(1);
	}
	/* do text section first */
	while (text_written < exec.a_text &&
	    (count = read(ifd, buf, sizeof (buf))) > 0) {
		if (count > exec.a_text - text_written)
			count = (exec.a_text - text_written);
		if (write(fd, buf, count) < count) {
			perror("write text file");
			exit(1);
		}
		text_written += count;
	}
	tot_write += text_written;
	if (lseek(ifd, dphdr.p_offset, 0) == -1) {
		perror("lseek data");
		exit(1);
	}
	while (data_written < exec.a_data &&
	    (count = read(ifd, buf, sizeof (buf))) > 0) {
		if (count > exec.a_data - data_written)
			count = (exec.a_data - data_written);
		if (write(fd, buf, count) < count) {
			perror("write data file");
			exit(1);
		}
		data_written += count;
	}
	tot_write += data_written;

	/*
	 * Round file size out to long word boundary.
	 * If the longword boundary is a multiple of 512 bytes,
	 * add another longword.
	 */
	lbytes = 0;
	if ((lalign = tot_write % sizeof (long)) != 0)
		lbytes = sizeof (long) - lalign;
	if (((lbytes + tot_write) % 512) == 0)
		lbytes += sizeof (long);

	if (lbytes != 0) {
		(void) printf("%s: (Align) 0x%x + 0x%x = 0x%x bytes\n", prog,
		    tot_write, lbytes, (tot_write + lbytes));
		if (write(fd, (char *)lalignbuf, lbytes) < lbytes) {
			perror("write (alignment) data file");
			exit(1);
		}
	}
	(void) close(fd);
	(void) close(ifd);
	return (0);
}