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rcsid[] and sccsid[] and copyright[] are essentially unmaintained (and
unmaintainable).  these days, people use source.  these id's do not provide
any benefit, and do hurt the small install media
(the 33,000 line diff is essentially mechanical)
ok with the idea millert, ok dms

/*	$OpenBSD: strip.c,v 1.26 2009/10/27 23:59:44 deraadt Exp $	*/

/*
 * Copyright (c) 1988 Regents of the University of California.
 * All rights reserved.
 *
 * 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. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
 */

#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <errno.h>
#include <a.out.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <err.h>
#include <ranlib.h>
#include "byte.c"

#ifdef MID_MACHINE_OVERRIDE
#undef MID_MACHINE
#define MID_MACHINE MID_MACHINE_OVERRIDE
#if MID_MACHINE_OVERRIDE == MID_M68K
#undef __LDPGSZ
#undef ELF_TARG_DATA
#undef ELF_TARG_MACH
#include "m68k/exec.h"
#elif MID_MACHINE_OVERRIDE == MID_M88K
#undef __LDPGSZ
#undef ELF_TARG_DATA
#undef ELF_TARG_MACH
#include "m88k/exec.h"
#endif
#endif

typedef struct exec EXEC;
typedef struct nlist NLIST;

#define	strx	n_un.n_strx

int s_stab(const char *, int, EXEC *, struct stat *, off_t *);
int s_sym(const char *, int, EXEC *, struct stat *, off_t *);
void usage(void);

int xflag = 0;
        
int
main(int argc, char *argv[])
{
	int fd;
	EXEC *ep;
	struct stat sb;
	int (*sfcn)(const char *, int, EXEC *, struct stat *, off_t *);
	int ch, errors;
	char *fn;
	off_t newsize;

	sfcn = s_sym;
	while ((ch = getopt(argc, argv, "dx")) != -1)
		switch(ch) {
                case 'x':
                        xflag = 1;
                        /*FALLTHROUGH*/
		case 'd':
			sfcn = s_stab;
			break;
		case '?':
		default:
			usage();
		}
	argc -= optind;
	argv += optind;

	errors = 0;
#define	ERROR(x) errors |= 1; warnx("%s: %s", fn, strerror(x)); continue;
	while ((fn = *argv++)) {
		if ((fd = open(fn, O_RDWR)) < 0) {
			ERROR(errno);
		}
        	if (fstat(fd, &sb)) {
			(void)close(fd);
			ERROR(errno);
		}
		if (sb.st_size < sizeof(EXEC)) {
			(void)close(fd);
			ERROR(EFTYPE);
		}
		if ((ep = (EXEC *)mmap(NULL, sb.st_size, PROT_READ|PROT_WRITE,
		    MAP_SHARED, fd, (off_t)0)) == MAP_FAILED) {
			(void)close(fd);
			ERROR(errno);
		}
		if (BAD_OBJECT(*ep)) {
			munmap((caddr_t)ep, sb.st_size);
			(void)close(fd);
			ERROR(EFTYPE);
		}
		/*
		 * Since we're dealing with an mmap there, we have to convert
		 * once for dealing with data in memory, and a second time
		 * for out.
		 */
		fix_header_order(ep);
		newsize = 0;
		errors |= sfcn(fn, fd, ep, &sb, &newsize);
		fix_header_order(ep);
		munmap((caddr_t)ep, sb.st_size);
		if (newsize  && ftruncate(fd, newsize)) {
			warn("%s", fn);
			errors = 1;
		}
		if (close(fd)) {
			ERROR(errno);
		}
	}
#undef ERROR
	exit(errors);
}

int
s_sym(const char *fn, int fd, EXEC *ep, struct stat *sp, off_t *sz)
{
	char *neweof;
#if	0
	char *mineof;
#endif
	int zmagic;

	zmagic = ep->a_data &&
		 (N_GETMAGIC(*ep) == ZMAGIC || N_GETMAGIC(*ep) == QMAGIC);

	/*
	 * If no symbols or data/text relocation info and
	 * the file data segment size is already minimized, quit.
	 */
	if (!ep->a_syms && !ep->a_trsize && !ep->a_drsize) {
#if 0
		if (!zmagic)
			return 0;
		if (sp->st_size < N_TRELOFF(*ep))
#endif
			return 0;
	}

	/*
	 * New file size is the header plus text and data segments; OMAGIC
	 * and NMAGIC formats have the text/data immediately following the
	 * header.  ZMAGIC format wastes the rest of of header page.
	 */
	neweof = (char *)ep + N_TRELOFF(*ep);

#if 0
	/*
	 * Unfortunately, this can't work correctly without changing the way
	 * the loader works.  We could cap it at one page, or even fiddle with
	 * a_data and a_bss, but this only works for CLBYTES == NBPG.  If we
	 * are on a system where, e.g., CLBYTES is 8k and NBPG is 4k, and we
	 * happen to remove 4.5k, we will lose.  And we really don't want to
	 * fiddle with pages, because that breaks binary compatibility.  Lose.
	 */

	if (zmagic) {
		/*
		 * Get rid of unneeded zeroes at the end of the data segment
		 * to reduce the file size even more.
		 */
		mineof = (char *)ep + N_DATOFF(*ep);
		while (neweof > mineof && neweof[-1] == '\0')
			neweof--;
	}
#endif

	/* Set symbol size and relocation info values to 0. */
	ep->a_syms = ep->a_trsize = ep->a_drsize = 0;

	/* Truncate the file. */
	*sz = neweof - (char *)ep;

	return 0;
}

int
s_stab(const char *fn, int fd, EXEC *ep, struct stat *sp, off_t *sz)
{
	int cnt, len;
	char *nstr, *nstrbase=0, *used=0, *p, *strbase;
	NLIST *sym, *nsym;
	u_long allocsize;
	int mid;
	NLIST *symbase;
	unsigned int *mapping=0;
	int error=1;
	unsigned int nsyms;
	struct relocation_info *reloc_base;
	unsigned int i, j;

	/* Quit if no symbols. */
	if (ep->a_syms == 0)
		return 0;

	if (N_SYMOFF(*ep) >= sp->st_size) {
		warnx("%s: bad symbol table", fn);
		return 1;
	}

	mid = N_GETMID(*ep);

	/*
	 * Initialize old and new symbol pointers.  They both point to the
	 * beginning of the symbol table in memory, since we're deleting
	 * entries.
	 */
	sym = nsym = symbase = (NLIST *)((char *)ep + N_SYMOFF(*ep));

	/*
	 * Allocate space for the new string table, initialize old and
	 * new string pointers.  Handle the extra long at the beginning
	 * of the string table.
	 */
	strbase = (char *)ep + N_STROFF(*ep);
	allocsize = fix_32_order(*(u_long *)strbase, mid);
	if ((nstrbase = malloc((u_int) allocsize)) == NULL) {
		warnx("%s", strerror(ENOMEM));
		goto end;
	}
	nstr = nstrbase + sizeof(u_long);

	/* okay, so we also need to keep symbol numbers for relocations. */
	nsyms = ep->a_syms/ sizeof(NLIST);
	used = calloc(nsyms, 1);
	if (!used) {
		warnx("%s", strerror(ENOMEM));
		goto end;
	}
	mapping = calloc(nsyms, sizeof(unsigned int));
	if (!mapping) {
		warnx("%s", strerror(ENOMEM));
		goto end;
	}

	if ((ep->a_trsize || ep->a_drsize) && byte_sex(mid) != BYTE_ORDER) {
		warnx("%s: cross-stripping not supported", fn);
		goto end;
	}

	/* first check the relocations for used symbols, and mark them */
	/* text */
	reloc_base = (struct relocation_info *) ((char *)ep + N_TRELOFF(*ep));
	if (N_TRELOFF(*ep) + ep->a_trsize > sp->st_size) {
		warnx("%s: bad text relocation", fn);
		goto end;
	}
	for (i = 0; i < ep->a_trsize / sizeof(struct relocation_info); i++) {
		if (!reloc_base[i].r_extern)
			continue;
		if (reloc_base[i].r_symbolnum > nsyms) {
			warnx("%s: bad symbol number in text relocation", fn);
			goto end;
		}
		used[reloc_base[i].r_symbolnum] = 1;
	}
	/* data */
	reloc_base = (struct relocation_info *) ((char *)ep + N_DRELOFF(*ep));
	if (N_DRELOFF(*ep) + ep->a_drsize > sp->st_size) {
		warnx("%s: bad data relocation", fn);
		goto end;
	}
	for (i = 0; i < ep->a_drsize / sizeof(struct relocation_info); i++) {
		if (!reloc_base[i].r_extern)
			continue;
		if (reloc_base[i].r_symbolnum > nsyms) {
			warnx("%s: bad symbol number in data relocation", fn);
			goto end;
		}
		used[reloc_base[i].r_symbolnum] = 1;
	}

	/*
	 * Read through the symbol table.  For each non-debugging symbol,
	 * copy it and save its string in the new string table.  Keep
	 * track of the number of symbols.
	 */
	for (cnt = nsyms, i = 0, j = 0; cnt--; ++sym, ++i) {
		fix_nlist_order(sym, mid);
		if (!(sym->n_type & N_STAB) && sym->strx) {
			*nsym = *sym;
			nsym->strx = nstr - nstrbase;
			p = strbase + sym->strx;
                        if (xflag && !used[i] &&
                            (!(sym->n_type & N_EXT) ||
                             (sym->n_type & ~N_EXT) == N_FN ||
                             strcmp(p, "gcc_compiled.") == 0 ||
                             strcmp(p, "gcc2_compiled.") == 0 ||
                             strncmp(p, "___gnu_compiled_", 16) == 0)) {
                                continue;
                        }
			len = strlen(p) + 1;
			mapping[i] = j++;
			if (N_STROFF(*ep) + sym->strx + len > sp->st_size) {
				warnx("%s: bad symbol table", fn);
				goto end;
			}
			bcopy(p, nstr, len);
			nstr += len;
			fix_nlist_order(nsym++, mid);
		}
	}

	/* renumber symbol relocations */
	/* text */
	reloc_base = (struct relocation_info *) ((char *)ep + N_TRELOFF(*ep));
	for (i = 0; i < ep->a_trsize / sizeof(struct relocation_info); i++) {
		if (!reloc_base[i].r_extern)
			continue;
		reloc_base[i].r_symbolnum = mapping[reloc_base[i].r_symbolnum];
	}
	/* data */
	reloc_base = (struct relocation_info *) ((char *)ep + N_DRELOFF(*ep));
	for (i = 0; i < ep->a_drsize / sizeof(struct relocation_info); i++) {
		if (!reloc_base[i].r_extern)
			continue;
		reloc_base[i].r_symbolnum = mapping[reloc_base[i].r_symbolnum];
	}

	/* Fill in new symbol table size. */
	ep->a_syms = (nsym - symbase) * sizeof(NLIST);

	/* Fill in the new size of the string table. */
	len = nstr - nstrbase;
	*(u_long *)nstrbase = fix_32_order(len, mid);

	/*
	 * Copy the new string table into place.  Nsym should be pointing
	 * at the address past the last symbol entry.
	 */
	bcopy(nstrbase, (void *)nsym, len);
	error = 0;
end:
	free(nstrbase);
	free(used);
	free(mapping);

	/* Truncate to the current length. */
	*sz = (char *)nsym + len - (char *)ep;

	return error;
}

void
usage(void)
{
	extern char *__progname;

	fprintf(stderr, "usage: %s [-dx] file ...\n", __progname);
	exit(1);
}