NetBSD/sys/compat/ibcs2/ibcs2_exec_coff.c

601 lines
18 KiB
C

/* $NetBSD: ibcs2_exec_coff.c,v 1.26 2013/10/25 14:46:35 martin Exp $ */
/*
* Copyright (c) 1994, 1995, 1998 Scott Bartram
* Copyright (c) 1994 Adam Glass
* Copyright (c) 1993, 1994 Christopher G. Demetriou
* All rights reserved.
*
* originally from kern/exec_ecoff.c
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Scott Bartram.
* 4. 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.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ibcs2_exec_coff.c,v 1.26 2013/10/25 14:46:35 martin Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/namei.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/exec.h>
#include <sys/exec_coff.h>
#include <sys/resourcevar.h>
#include <sys/mman.h>
#include <sys/cpu.h>
#include <machine/reg.h>
#include <machine/ibcs2_machdep.h>
#include <compat/ibcs2/ibcs2_types.h>
#include <compat/ibcs2/ibcs2_exec.h>
#include <compat/ibcs2/ibcs2_errno.h>
#include <compat/ibcs2/ibcs2_util.h>
int exec_ibcs2_coff_prep_omagic(struct lwp *, struct exec_package *,
struct coff_filehdr *,
struct coff_aouthdr *);
int exec_ibcs2_coff_prep_nmagic(struct lwp *, struct exec_package *,
struct coff_filehdr *,
struct coff_aouthdr *);
int exec_ibcs2_coff_prep_zmagic(struct lwp *, struct exec_package *,
struct coff_filehdr *,
struct coff_aouthdr *);
void cpu_exec_ibcs2_coff_setup(int, struct proc *, struct exec_package *,
void *);
static int coff_load_shlib(struct lwp *, const char *,
struct exec_package *);
static int coff_find_section(struct lwp *, struct vnode *,
struct coff_filehdr *, struct coff_scnhdr *,
int);
/*
* exec_ibcs2_coff_makecmds(): Check if it's an coff-format executable.
*
* Given a proc pointer and an exec package pointer, see if the referent
* of the epp is in coff format. Check 'standard' magic numbers for
* this architecture. If that fails, return failure.
*
* This function is responsible for creating a set of vmcmds which can be
* used to build the process's vm space and inserting them into the exec
* package.
*/
int
exec_ibcs2_coff_makecmds(struct lwp *l, struct exec_package *epp)
{
int error;
struct coff_filehdr *fp = epp->ep_hdr;
struct coff_aouthdr *ap;
if (epp->ep_hdrvalid < COFF_HDR_SIZE) {
DPRINTF(("ibcs2: bad coff hdr size\n"));
return ENOEXEC;
}
if (COFF_BADMAG(fp)) {
DPRINTF(("ibcs2: bad coff magic\n"));
return ENOEXEC;
}
ap = (void *)((char *)epp->ep_hdr + sizeof(struct coff_filehdr));
switch (ap->a_magic) {
case COFF_OMAGIC:
error = exec_ibcs2_coff_prep_omagic(l, epp, fp, ap);
break;
case COFF_NMAGIC:
error = exec_ibcs2_coff_prep_nmagic(l, epp, fp, ap);
break;
case COFF_ZMAGIC:
error = exec_ibcs2_coff_prep_zmagic(l, epp, fp, ap);
break;
default:
DPRINTF(("ibcs2: bad coff magic %x\n", ap->a_magic));
return ENOEXEC;
}
if (error) {
kill_vmcmds(&epp->ep_vmcmds);
DPRINTF(("ibcs2: error loading magic %x (%d)\n", ap->a_magic,
error));
}
return error;
}
/*
* exec_ibcs2_coff_prep_omagic(): Prepare a COFF OMAGIC binary's exec package
*/
int
exec_ibcs2_coff_prep_omagic(struct lwp *l, struct exec_package *epp, struct coff_filehdr *fp, struct coff_aouthdr *ap)
{
epp->ep_taddr = COFF_SEGMENT_ALIGN(fp, ap, ap->a_tstart);
epp->ep_tsize = ap->a_tsize;
epp->ep_daddr = COFF_SEGMENT_ALIGN(fp, ap, ap->a_dstart);
epp->ep_dsize = ap->a_dsize;
epp->ep_entry = ap->a_entry;
DPRINTF(("ibcs2_omagic: text=%#lx/%#lx, data=%#lx/%#lx, bss=%#lx/%#lx, entry=%#lx\n",
epp->ep_taddr, epp->ep_tsize,
epp->ep_daddr, epp->ep_dsize,
ap->a_dstart + ap->a_dsize, ap->a_bsize,
epp->ep_entry));
/* set up command for text and data segments */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
ap->a_tsize + ap->a_dsize, epp->ep_taddr, epp->ep_vp,
COFF_TXTOFF(fp, ap),
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* set up command for bss segment */
if (ap->a_bsize > 0) {
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, ap->a_bsize,
COFF_SEGMENT_ALIGN(fp, ap, ap->a_dstart + ap->a_dsize),
NULLVP, 0,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
epp->ep_dsize += ap->a_bsize;
}
/* The following is to make obreak(2) happy. It expects daddr
* to on a page boundary and will round up dsize to a page
* address.
*/
if (trunc_page(epp->ep_daddr) != epp->ep_daddr) {
epp->ep_dsize += epp->ep_daddr - trunc_page(epp->ep_daddr);
epp->ep_daddr = trunc_page(epp->ep_daddr);
if (epp->ep_taddr + epp->ep_tsize > epp->ep_daddr)
epp->ep_tsize = epp->ep_daddr - epp->ep_taddr;
}
return (*epp->ep_esch->es_setup_stack)(l, epp);
}
/*
* exec_ibcs2_coff_prep_nmagic(): Prepare a 'native' NMAGIC COFF binary's exec
* package.
*/
int
exec_ibcs2_coff_prep_nmagic(struct lwp *l, struct exec_package *epp, struct coff_filehdr *fp, struct coff_aouthdr *ap)
{
long toverlap, doverlap;
u_long tsize, tend;
epp->ep_taddr = ap->a_tstart;
epp->ep_tsize = ap->a_tsize;
epp->ep_daddr = ap->a_dstart;
epp->ep_dsize = ap->a_dsize;
epp->ep_entry = ap->a_entry;
DPRINTF(("ibcs2_nmagic: text=%#lx/%#lx, data=%#lx/%#lx, bss=%#lx/%#lx, entry=%#lx\n",
epp->ep_taddr, epp->ep_tsize,
epp->ep_daddr, epp->ep_dsize,
ap->a_dstart + ap->a_dsize, ap->a_bsize,
epp->ep_entry));
/* Do the text and data pages overlap?
*/
tend = epp->ep_taddr + epp->ep_tsize - 1;
if (trunc_page(tend) == trunc_page(epp->ep_daddr)) {
/* If the first page of text is the first page of data,
* then we consider it all data.
*/
if (trunc_page(epp->ep_taddr) == trunc_page(epp->ep_daddr)) {
tsize = 0;
} else {
tsize = trunc_page(tend) - epp->ep_taddr;
}
/* If the text and data file and VA offsets are the
* same, simply bring the data segment to start on
* the start of the page.
*/
if (epp->ep_daddr - epp->ep_taddr ==
COFF_DATOFF(fp, ap) - COFF_TXTOFF(fp, ap)) {
u_long diff = epp->ep_daddr - trunc_page(epp->ep_daddr);
toverlap = 0;
doverlap = -diff;
} else {
/* otherwise copy the individual pieces */
toverlap = epp->ep_tsize - tsize;
doverlap = round_page(epp->ep_daddr) - epp->ep_daddr;
if (doverlap > epp->ep_dsize)
doverlap = epp->ep_dsize;
}
} else {
tsize = epp->ep_tsize;
toverlap = 0;
doverlap = 0;
}
DPRINTF(("nmagic_vmcmds:"));
if (tsize > 0) {
/* set up command for text segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, tsize,
epp->ep_taddr, epp->ep_vp, COFF_TXTOFF(fp, ap),
VM_PROT_READ|VM_PROT_EXECUTE);
DPRINTF((" map_readvn(%#lx/%#lx@%#lx)",
epp->ep_taddr, tsize, (u_long) COFF_TXTOFF(fp, ap)));
}
if (toverlap > 0) {
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, toverlap,
epp->ep_taddr + tsize, epp->ep_vp,
COFF_TXTOFF(fp, ap) + tsize,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
DPRINTF((" map_readvn(%#lx/%#lx@%#lx)",
epp->ep_taddr + tsize, toverlap,
COFF_TXTOFF(fp, ap) + tsize));
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_readvn, doverlap,
epp->ep_daddr, epp->ep_vp,
COFF_DATOFF(fp, ap),
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
DPRINTF((" readvn(%#lx/%#lx@%#lx)", epp->ep_daddr, doverlap,
COFF_DATOFF(fp, ap)));
}
if (epp->ep_dsize > doverlap || doverlap < 0) {
/* set up command for data segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
epp->ep_dsize - doverlap, epp->ep_daddr + doverlap,
epp->ep_vp, COFF_DATOFF(fp, ap) + doverlap,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
DPRINTF((" map_readvn(%#lx/%#lx@%#lx)",
epp->ep_daddr + doverlap, epp->ep_dsize - doverlap,
COFF_DATOFF(fp, ap) + doverlap));
}
/* Handle page remainders for pagedvn.
*/
/* set up command for bss segment */
if (ap->a_bsize > 0) {
u_long dend = round_page(epp->ep_daddr + epp->ep_dsize);
u_long dspace = dend - (epp->ep_daddr + epp->ep_dsize);
if (ap->a_bsize > dspace) {
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero,
ap->a_bsize - dspace, dend, NULLVP, 0,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
DPRINTF((" map_zero(%#lx/%#lx)",
dend, ap->a_bsize - dspace));
}
epp->ep_dsize += ap->a_bsize;
}
DPRINTF(("\n"));
/* The following is to make obreak(2) happy. It expects daddr
* to on a page boundary and will round up dsize to a page
* address.
*/
if (trunc_page(epp->ep_daddr) != epp->ep_daddr) {
epp->ep_dsize += epp->ep_daddr - trunc_page(epp->ep_daddr);
epp->ep_daddr = trunc_page(epp->ep_daddr);
if (epp->ep_taddr + epp->ep_tsize > epp->ep_daddr)
epp->ep_tsize = epp->ep_daddr - epp->ep_taddr;
}
return (*epp->ep_esch->es_setup_stack)(l, epp);
}
/*
* coff_find_section - load specified section header
*
* TODO - optimize by reading all section headers in at once
*/
static int
coff_find_section(struct lwp *l, struct vnode *vp, struct coff_filehdr *fp, struct coff_scnhdr *sh, int s_type)
{
int i, pos, siz, error;
size_t resid;
pos = COFF_HDR_SIZE;
for (i = 0; i < fp->f_nscns; i++, pos += sizeof(struct coff_scnhdr)) {
siz = sizeof(struct coff_scnhdr);
error = vn_rdwr(UIO_READ, vp, (void *) sh,
siz, pos, UIO_SYSSPACE, IO_NODELOCKED, l->l_cred,
&resid, NULL);
if (error) {
DPRINTF(("section hdr %d read error %d\n", i, error));
return error;
}
siz -= resid;
if (siz != sizeof(struct coff_scnhdr)) {
DPRINTF(("incomplete read: hdr %d ask=%d, rem=%lu got %d\n",
s_type, sizeof(struct coff_scnhdr),
(u_long) resid, siz));
return ENOEXEC;
}
/* DPRINTF(("found section: %x\n", sh->s_flags)); */
if (sh->s_flags == s_type)
return 0;
}
return ENOEXEC;
}
/*
* exec_ibcs2_coff_prep_zmagic(): Prepare a COFF ZMAGIC binary's exec package
*
* First, set the various offsets/lengths in the exec package.
*
* Then, mark the text image busy (so it can be demand paged) or error
* out if this is not possible. Finally, set up vmcmds for the
* text, data, bss, and stack segments.
*/
int
exec_ibcs2_coff_prep_zmagic(struct lwp *l, struct exec_package *epp, struct coff_filehdr *fp, struct coff_aouthdr *ap)
{
int error;
u_long offset;
long dsize, baddr, bsize;
struct coff_scnhdr sh;
/* DPRINTF(("enter exec_ibcs2_coff_prep_zmagic\n")); */
/* set up command for text segment */
error = coff_find_section(l, epp->ep_vp, fp, &sh, COFF_STYP_TEXT);
if (error) {
DPRINTF(("can't find text section: %d\n", error));
return error;
}
/* DPRINTF(("COFF text addr %x size %d offset %d\n", sh.s_vaddr,
sh.s_size, sh.s_scnptr)); */
epp->ep_taddr = COFF_ALIGN(sh.s_vaddr);
offset = sh.s_scnptr - (sh.s_vaddr - epp->ep_taddr);
epp->ep_tsize = sh.s_size + (sh.s_vaddr - epp->ep_taddr);
/* DPRINTF(("VMCMD: addr %x size %d offset %d\n", epp->ep_taddr,
epp->ep_tsize, offset)); */
#ifdef notyet
error = vn_marktext(epp->ep_vp);
if (error)
return (error);
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, epp->ep_tsize,
epp->ep_taddr, epp->ep_vp, offset,
VM_PROT_READ|VM_PROT_EXECUTE);
#else
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, epp->ep_tsize,
epp->ep_taddr, epp->ep_vp, offset,
VM_PROT_READ|VM_PROT_EXECUTE);
#endif
/* set up command for data segment */
error = coff_find_section(l, epp->ep_vp, fp, &sh, COFF_STYP_DATA);
if (error) {
DPRINTF(("can't find data section: %d\n", error));
return error;
}
/* DPRINTF(("COFF data addr %x size %d offset %d\n", sh.s_vaddr,
sh.s_size, sh.s_scnptr)); */
epp->ep_daddr = COFF_ALIGN(sh.s_vaddr);
offset = sh.s_scnptr - (sh.s_vaddr - epp->ep_daddr);
dsize = sh.s_size + (sh.s_vaddr - epp->ep_daddr);
epp->ep_dsize = dsize + ap->a_bsize;
/* DPRINTF(("VMCMD: addr %x size %d offset %d\n", epp->ep_daddr,
dsize, offset)); */
#ifdef notyet
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, dsize,
epp->ep_daddr, epp->ep_vp, offset,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
#else
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
dsize, epp->ep_daddr, epp->ep_vp, offset,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
#endif
/* set up command for bss segment */
baddr = round_page(epp->ep_daddr + dsize);
bsize = epp->ep_daddr + epp->ep_dsize - baddr;
if (bsize > 0) {
/* DPRINTF(("VMCMD: addr %x size %d offset %d\n",
baddr, bsize, 0)); */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero,
bsize, baddr, NULLVP, 0,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
}
/* load any shared libraries */
error = coff_find_section(l, epp->ep_vp, fp, &sh, COFF_STYP_SHLIB);
if (!error) {
size_t resid;
struct coff_slhdr *slhdr;
char *tbuf, *bufp;
size_t len = sh.s_size, /* path_index, */ entry_len;
if (len > 64 * 1024)
return ENOEXEC;
tbuf = malloc(len, M_TEMP, M_WAITOK);
if (tbuf == NULL)
return ENOEXEC;
/* DPRINTF(("COFF shlib size %d offset %d\n",
sh.s_size, sh.s_scnptr)); */
error = vn_rdwr(UIO_READ, epp->ep_vp, tbuf,
len, sh.s_scnptr,
UIO_SYSSPACE, IO_NODELOCKED, l->l_cred,
&resid, NULL);
if (error) {
DPRINTF(("shlib section read error %d\n", error));
free(tbuf, M_TEMP);
return ENOEXEC;
}
bufp = tbuf;
while (len) {
slhdr = (struct coff_slhdr *)bufp;
if (slhdr->path_index > LONG_MAX / sizeof(long) ||
slhdr->entry_len > LONG_MAX / sizeof(long)) {
free(tbuf, M_TEMP);
return ENOEXEC;
}
/* path_index = slhdr->path_index * sizeof(long); */
entry_len = slhdr->entry_len * sizeof(long);
if (entry_len > len) {
free(tbuf, M_TEMP);
return ENOEXEC;
}
/* DPRINTF(("path_index: %d entry_len: %d name: %s\n",
path_index, entry_len, slhdr->sl_name)); */
error = coff_load_shlib(l, slhdr->sl_name, epp);
if (error) {
free(tbuf, M_TEMP);
return ENOEXEC;
}
bufp += entry_len;
len -= entry_len;
}
free(tbuf, M_TEMP);
}
/* set up entry point */
epp->ep_entry = ap->a_entry;
DPRINTF(("ibcs2_zmagic: text addr: %#lx size: %#lx data addr: %#lx size: %#lx entry: %#lx\n",
epp->ep_taddr, epp->ep_tsize,
epp->ep_daddr, epp->ep_dsize,
epp->ep_entry));
/* The following is to make obreak(2) happy. It expects daddr
* to on a page boundary and will round up dsize to a page
* address.
*/
if (trunc_page(epp->ep_daddr) != epp->ep_daddr) {
epp->ep_dsize += epp->ep_daddr - trunc_page(epp->ep_daddr);
epp->ep_daddr = trunc_page(epp->ep_daddr);
if (epp->ep_taddr + epp->ep_tsize > epp->ep_daddr)
epp->ep_tsize = epp->ep_daddr - epp->ep_taddr;
}
return (*epp->ep_esch->es_setup_stack)(l, epp);
}
static int
coff_load_shlib(struct lwp *l, const char *path, struct exec_package *epp)
{
int error, siz;
int taddr, tsize, daddr, dsize, offset;
size_t resid;
struct vnode *vp;
struct coff_filehdr fh, *fhp = &fh;
struct coff_scnhdr sh, *shp = &sh;
/*
* 1. open shlib file
* 2. read filehdr
* 3. map text, data, and bss out of it using VM_*
*/
/* first get the vnode */
error = namei_simple_kernel(path, NSM_FOLLOW_TRYEMULROOT, &vp);
if (error != 0) {
DPRINTF(("coff_load_shlib: can't find library %s\n", path));
return error;
}
siz = sizeof(struct coff_filehdr);
error = vn_rdwr(UIO_READ, vp, (void *) fhp, siz, 0,
UIO_SYSSPACE, IO_NODELOCKED, l->l_cred, &resid, l);
if (error) {
DPRINTF(("filehdr read error %d\n", error));
vrele(vp);
return error;
}
siz -= resid;
if (siz != sizeof(struct coff_filehdr)) {
DPRINTF(("coff_load_shlib: incomplete read: ask=%d, rem=%lu got %d\n",
sizeof(struct coff_filehdr), (u_long) resid, siz));
vrele(vp);
return ENOEXEC;
}
/* load text */
error = coff_find_section(l, vp, fhp, shp, COFF_STYP_TEXT);
if (error) {
DPRINTF(("can't find shlib text section\n"));
vrele(vp);
return error;
}
/* DPRINTF(("COFF text addr %x size %d offset %d\n", sh.s_vaddr,
sh.s_size, sh.s_scnptr)); */
taddr = COFF_ALIGN(shp->s_vaddr);
offset = shp->s_scnptr - (shp->s_vaddr - taddr);
tsize = shp->s_size + (shp->s_vaddr - taddr);
/* DPRINTF(("VMCMD: addr %x size %d offset %d\n", taddr, tsize, offset)); */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, tsize, taddr,
vp, offset,
VM_PROT_READ|VM_PROT_EXECUTE);
/* load data */
error = coff_find_section(l, vp, fhp, shp, COFF_STYP_DATA);
if (error) {
DPRINTF(("can't find shlib data section\n"));
vrele(vp);
return error;
}
/* DPRINTF(("COFF data addr %x size %d offset %d\n", shp->s_vaddr,
shp->s_size, shp->s_scnptr)); */
daddr = COFF_ALIGN(shp->s_vaddr);
offset = shp->s_scnptr - (shp->s_vaddr - daddr);
dsize = shp->s_size + (shp->s_vaddr - daddr);
/* epp->ep_dsize = dsize + ap->a_bsize; */
/* DPRINTF(("VMCMD: addr %x size %d offset %d\n", daddr, dsize, offset)); */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
dsize, daddr, vp, offset,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* load bss */
error = coff_find_section(l, vp, fhp, shp, COFF_STYP_BSS);
if (!error) {
int baddr = round_page(daddr + dsize);
int bsize = daddr + dsize + shp->s_size - baddr;
if (bsize > 0) {
/* DPRINTF(("VMCMD: addr %x size %d offset %d\n",
baddr, bsize, 0)); */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero,
bsize, baddr, NULLVP, 0,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
}
}
vrele(vp);
return 0;
}