pe_section.c

/*-
 * Copyright (c) 2016 Kai Wang
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 <errno.h>
#include <string.h>

#include "_libpe.h"

ELFTC_VCSID("$Id: pe_section.c 3312 2016-01-10 09:23:51Z kaiwang27 $");

PE_Scn *
pe_getscn(PE *pe, size_t ndx)
{
	PE_Scn *ps;

	if (pe == NULL || ndx < 1 || ndx > 0xFFFFU) {
		errno = EINVAL;
		return (NULL);
	}

	STAILQ_FOREACH(ps, &pe->pe_scn, ps_next) {
		if (ps->ps_ndx == ndx)
			return (ps);
	}

	errno = ENOENT;

	return (NULL);
}

size_t
pe_ndxscn(PE_Scn *ps)
{

	if (ps == NULL) {
		errno = EINVAL;
		return (0);
	}

	return (ps->ps_ndx);
}

PE_Scn *
pe_nextscn(PE *pe, PE_Scn *ps)
{

	if (pe == NULL) {
		errno = EINVAL;
		return (NULL);
	}

	if (ps == NULL)
		ps = STAILQ_FIRST(&pe->pe_scn);
	else
		ps = STAILQ_NEXT(ps, ps_next);

	while (ps != NULL) {
		if (ps->ps_ndx >= 1 && ps->ps_ndx <= 0xFFFFU)
			return (ps);
		ps = STAILQ_NEXT(ps, ps_next);
	}

	return (NULL);
}

PE_Scn *
pe_newscn(PE *pe)
{
	PE_Scn *ps, *tps, *_tps;

	if (pe == NULL) {
		errno = EINVAL;
		return (NULL);
	}

	if (pe->pe_cmd == PE_C_READ || pe->pe_flags & LIBPE_F_FD_DONE) {
		errno = EACCES;
		return (NULL);
	}

	if ((ps = libpe_alloc_scn(pe)) == NULL)
		return (NULL);

	if (pe->pe_flags & LIBPE_F_BAD_SEC_HEADER) {
		STAILQ_FOREACH_SAFE(tps, &pe->pe_scn, ps_next, _tps)
			libpe_release_scn(tps);
		pe->pe_flags &= ~LIBPE_F_BAD_SEC_HEADER;
	}

	STAILQ_INSERT_TAIL(&pe->pe_scn, ps, ps_next);

	ps->ps_flags |= PE_F_DIRTY | LIBPE_F_LOAD_SECTION;
	pe->pe_flags |= LIBPE_F_DIRTY_SEC_HEADER;

	return (ps);
}

PE_Scn *
pe_insertscn(PE *pe, size_t ndx)
{
	PE_Scn *ps, *a, *b;

	if (pe == NULL || ndx < 1 || ndx > 0xFFFFU) {
		errno = EINVAL;
		return (NULL);
	}

	if (pe->pe_cmd == PE_C_READ || pe->pe_flags & LIBPE_F_FD_DONE) {
		errno = EACCES;
		return (NULL);
	}

	if ((ps = libpe_alloc_scn(pe)) == NULL)
		return (NULL);

	if (pe->pe_flags & LIBPE_F_BAD_SEC_HEADER) {
		STAILQ_FOREACH_SAFE(a, &pe->pe_scn, ps_next, b)
			libpe_release_scn(a);
		pe->pe_flags &= ~LIBPE_F_BAD_SEC_HEADER;
	}

	b = NULL;
	STAILQ_FOREACH(a, &pe->pe_scn, ps_next) {
		if (a->ps_ndx & 0xFFFF0000U)
			continue;
		if (a->ps_ndx == ndx)
			break;
		b = a;
	}

	if (a == NULL) {
		STAILQ_INSERT_TAIL(&pe->pe_scn, ps, ps_next);
		if (b == NULL)
			ps->ps_ndx = 1;
		else
			ps->ps_ndx = b->ps_ndx + 1;
	} else if (b == NULL) {
		STAILQ_INSERT_HEAD(&pe->pe_scn, ps, ps_next);
		ps->ps_ndx = 1;
	} else {
		STAILQ_INSERT_AFTER(&pe->pe_scn, b, ps, ps_next);
		ps->ps_ndx = ndx;
	}

	a = ps;
	while ((a = STAILQ_NEXT(a, ps_next)) != NULL) {
		if ((a->ps_ndx & 0xFFFF0000U) == 0)
			a->ps_ndx++;
	}

	ps->ps_flags |= PE_F_DIRTY | LIBPE_F_LOAD_SECTION;
	pe->pe_flags |= LIBPE_F_DIRTY_SEC_HEADER;

	return (ps);
}

PE_SecHdr *
pe_section_header(PE_Scn *ps)
{

	if (ps == NULL) {
		errno = EINVAL;
		return (NULL);
	}

	return (&ps->ps_sh);
}

int
pe_update_section_header(PE_Scn *ps, PE_SecHdr *sh)
{
	PE *pe;

	if (ps == NULL || sh == NULL) {
		errno = EINVAL;
		return (-1);
	}

	pe = ps->ps_pe;

	if (pe->pe_cmd == PE_C_READ || pe->pe_flags & LIBPE_F_FD_DONE) {
		errno = EACCES;
		return (-1);
	}

	ps->ps_sh = *sh;
	pe->pe_flags |= LIBPE_F_DIRTY_SEC_HEADER;

	return (0);
}