NetBSD/usr.bin/kdump/kdump.c

947 lines
20 KiB
C

/* $NetBSD: kdump.c,v 1.72 2004/01/15 14:42:09 mrg Exp $ */
/*-
* Copyright (c) 1988, 1993
* The 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/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1988, 1993\n\
The Regents of the University of California. All rights reserved.\n");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)kdump.c 8.4 (Berkeley) 4/28/95";
#else
__RCSID("$NetBSD: kdump.c,v 1.72 2004/01/15 14:42:09 mrg Exp $");
#endif
#endif /* not lint */
#include <sys/param.h>
#define _KERNEL
#include <sys/errno.h>
#undef _KERNEL
#include <sys/time.h>
#include <sys/uio.h>
#include <sys/ktrace.h>
#include <sys/ioctl.h>
#include <sys/ptrace.h>
#include <ctype.h>
#include <err.h>
#include <signal.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <vis.h>
#include "ktrace.h"
#include "setemul.h"
#include <sys/syscall.h>
int timestamp, decimal, plain, tail, maxdata = -1, numeric;
int word_size = 0;
pid_t do_pid = -1;
const char *tracefile = NULL;
struct ktr_header ktr_header;
int emul_changed = 0;
#define eqs(s1, s2) (strcmp((s1), (s2)) == 0)
static const char *ptrace_ops[] = {
"PT_TRACE_ME", "PT_READ_I", "PT_READ_D", "PT_READ_U",
"PT_WRITE_I", "PT_WRITE_D", "PT_WRITE_U", "PT_CONTINUE",
"PT_KILL", "PT_ATTACH", "PT_DETACH",
};
static const char *linux_ptrace_ops[] = {
"PTRACE_TRACEME",
"PTRACE_PEEKTEXT", "PTRACE_PEEKDATA", "PTRACE_PEEKUSER",
"PTRACE_POKETEXT", "PTRACE_POKEDATA", "PTRACE_POKEUSER",
"PTRACE_CONT", "PTRACE_KILL", "PTRACE_SINGLESTEP",
NULL, NULL,
"PTRACE_GETREGS", "PTRACE_SETREGS", "PTRACE_GETFPREGS",
"PTRACE_SETFPREGS", "PTRACE_ATTACH", "PTRACE_DETACH",
"PTRACE_SYSCALL",
};
int main(int, char **);
int fread_tail(char *, int, int);
int dumpheader(struct ktr_header *);
void output_long(u_long, int);
void ioctldecode(u_long);
void ktrsyscall(struct ktr_syscall *);
void ktrsyscall_size(struct ktr_syscall *);
void ktrsysret(struct ktr_sysret *, int);
void ktrnamei(char *, int);
void ktremul(char *, int, int);
void ktrgenio(struct ktr_genio *, int);
void ktrpsig(void *, int);
void ktrcsw(struct ktr_csw *);
void ktruser(struct ktr_user *, int);
void ktrmmsg(struct ktr_mmsg *, int);
void ktrmool(struct ktr_mool *, int);
void usage(void);
void eprint(int);
void rprint(register_t);
char *ioctlname(long);
static const char *signame(long, int);
static void hexdump_buf(const void *, int, int);
static void visdump_buf(const void *, int, int);
int
main(argc, argv)
int argc;
char **argv;
{
int ch, ktrlen, size;
void *m;
int trpoints = 0;
int trset = 0;
const char *emul_name = "netbsd";
int col;
char *cp;
while ((ch = getopt(argc, argv, "e:f:dlm:Nnp:RTt:xX:")) != -1) {
switch (ch) {
case 'e':
emul_name = strdup(optarg); /* it's safer to copy it */
break;
case 'f':
tracefile = optarg;
break;
case 'd':
decimal = 1;
break;
case 'l':
tail = 1;
break;
case 'p':
do_pid = strtoul(optarg, &cp, 0);
if (*cp != 0)
errx(1,"invalid number %s", optarg);
break;
case 'm':
maxdata = strtoul(optarg, &cp, 0);
if (*cp != 0)
errx(1,"invalid number %s", optarg);
break;
case 'N':
numeric++;
break;
case 'n':
plain++;
break;
case 'R':
timestamp = 2; /* relative timestamp */
break;
case 'T':
timestamp = 1;
break;
case 't':
trset = 1;
trpoints = getpoints(trpoints, optarg);
if (trpoints < 0)
errx(1, "unknown trace point in %s", optarg);
break;
case 'x':
word_size = 1;
break;
case 'X':
word_size = strtoul(optarg, &cp, 0);
if (*cp != 0 || word_size & (word_size - 1) ||
word_size > 16 || word_size <= 0)
errx(1, "argument to -X must be "
"1, 2, 4, 8 or 16");
break;
default:
usage();
}
}
argv += optind;
argc -= optind;
if (!trset)
trpoints = ALL_POINTS;
if (tracefile == NULL) {
if (argc == 1) {
tracefile = argv[0];
argv++;
argc--;
}
else
tracefile = DEF_TRACEFILE;
}
if (argc > 0)
usage();
setemul(emul_name, 0, 0);
mach_lookup_emul();
m = malloc(size = 1024);
if (m == NULL)
errx(1, "malloc: %s", strerror(ENOMEM));
if (!freopen(tracefile, "r", stdin))
err(1, "%s", tracefile);
while (fread_tail((char *)&ktr_header, sizeof(struct ktr_header), 1)) {
if (trpoints & (1<<ktr_header.ktr_type)
&& (do_pid == -1 || ktr_header.ktr_pid == do_pid))
col = dumpheader(&ktr_header);
else
col = -1;
if ((ktrlen = ktr_header.ktr_len) < 0)
errx(1, "bogus length 0x%x", ktrlen);
if (ktrlen > size) {
while (ktrlen > size)
size *= 2;
m = realloc(m, size);
if (m == NULL)
errx(1, "realloc: %s", strerror(ENOMEM));
}
if (ktrlen && fread_tail(m, ktrlen, 1) == 0)
errx(1, "data too short");
if (col == -1)
continue;
/* update context to match currently processed record */
ectx_sanify(ktr_header.ktr_pid);
switch (ktr_header.ktr_type) {
case KTR_SYSCALL:
ktrsyscall(m);
break;
case KTR_SYSRET:
ktrsysret(m, ktrlen);
break;
case KTR_NAMEI:
ktrnamei(m, ktrlen);
break;
case KTR_GENIO:
ktrgenio(m, ktrlen);
break;
case KTR_PSIG:
ktrpsig(m, ktrlen);
break;
case KTR_CSW:
ktrcsw(m);
break;
case KTR_EMUL:
ktremul(m, ktrlen, size);
break;
case KTR_USER:
ktruser(m, ktrlen);
break;
case KTR_MMSG:
ktrmmsg(m, ktrlen);
break;
case KTR_MOOL:
ktrmool(m, ktrlen);
break;
case KTR_EXEC_ARG:
case KTR_EXEC_ENV:
visdump_buf(m, ktrlen, col);
break;
default:
putchar('\n');
hexdump_buf(m, ktrlen, word_size);
}
if (tail)
(void)fflush(stdout);
}
return (0);
}
int
fread_tail(buf, size, num)
char *buf;
int num, size;
{
int i;
while ((i = fread(buf, size, num, stdin)) == 0 && tail) {
(void)sleep(1);
clearerr(stdin);
}
return (i);
}
int
dumpheader(kth)
struct ktr_header *kth;
{
char unknown[64], *type;
static struct timeval prevtime;
struct timeval temp;
int col;
switch (kth->ktr_type) {
case KTR_SYSCALL:
type = "CALL";
break;
case KTR_SYSRET:
type = "RET ";
break;
case KTR_NAMEI:
type = "NAMI";
break;
case KTR_GENIO:
type = "GIO ";
break;
case KTR_PSIG:
type = "PSIG";
break;
case KTR_CSW:
type = "CSW ";
break;
case KTR_EMUL:
type = "EMUL";
break;
case KTR_USER:
type = "USER";
break;
case KTR_MMSG:
type = "MMSG";
break;
case KTR_MOOL:
type = "MOOL";
break;
case KTR_EXEC_ENV:
type = "ENV";
break;
case KTR_EXEC_ARG:
type = "ARG";
break;
default:
(void)sprintf(unknown, "UNKNOWN(%d)", kth->ktr_type);
type = unknown;
}
col = printf("%6d %-8.*s ", kth->ktr_pid, MAXCOMLEN, kth->ktr_comm);
if (timestamp) {
if (timestamp == 2) {
if (prevtime.tv_sec == 0)
temp.tv_sec = temp.tv_usec = 0;
else
timersub(&kth->ktr_time, &prevtime, &temp);
prevtime = kth->ktr_time;
} else
temp = kth->ktr_time;
col += printf("%ld.%06ld ",
(long int)temp.tv_sec, (long int)temp.tv_usec);
}
col += printf("%-4s ", type);
return col;
}
void
output_long(it, as_x)
u_long it;
int as_x;
{
if (cur_emul->flags & EMUL_FLAG_NETBSD32)
printf(as_x ? "%#x" : "%d", (u_int)it);
else
printf(as_x ? "%#lx" : "%ld", it);
}
void
ioctldecode(cmd)
u_long cmd;
{
char dirbuf[4], *dir = dirbuf;
if (cmd & IOC_IN)
*dir++ = 'W';
if (cmd & IOC_OUT)
*dir++ = 'R';
*dir = '\0';
printf(",_IO%s('%c',", dirbuf, (int) ((cmd >> 8) & 0xff));
output_long(cmd & 0xff, decimal == 0);
if ((cmd & IOC_VOID) == 0) {
putchar(',');
output_long((cmd >> 16) & 0xff, decimal == 0);
}
putchar(')');
}
void
ktrsyscall(ktr)
struct ktr_syscall *ktr;
{
int argcount;
const struct emulation *emul = cur_emul;
register_t *ap;
char c;
char *cp;
const char *sys_name;
argcount = ktr->ktr_argsize / sizeof (*ap);
emul_changed = 0;
if (numeric ||
((ktr->ktr_code >= emul->nsysnames || ktr->ktr_code < 0)
&& mach_traps_dispatch(&ktr->ktr_code, &emul) == 0)) {
sys_name = "?";
(void)printf("[%d]", ktr->ktr_code);
} else {
sys_name = emul->sysnames[ktr->ktr_code];
(void)printf("%s", sys_name);
}
#ifdef _LP64
#define NETBSD32_ "netbsd32_"
if (cur_emul->flags & EMUL_FLAG_NETBSD32) {
size_t len = strlen(NETBSD32_);
if (strncmp(sys_name, NETBSD32_, len) == 0)
sys_name += len;
}
#undef NETBSD32_
#endif
ap = (register_t *)((char *)ktr + sizeof(struct ktr_syscall));
if (argcount) {
c = '(';
if (plain) {
;
} else if (strcmp(sys_name, "exit") == 0) {
ectx_delete();
} else if (strcmp(sys_name, "ioctl") == 0 && argcount >= 2) {
(void)putchar('(');
output_long((long)*ap, (decimal || *ap <= 9));
ap++;
argcount--;
if ((cp = ioctlname(*ap)) != NULL)
(void)printf(",%s", cp);
else
ioctldecode(*ap);
ap++;
argcount--;
c = ',';
} else if (strcmp(sys_name, "kill") == 0 && argcount >= 2) {
putchar('(');
output_long((long)ap[0], (decimal || *ap <= 9));
(void)printf(", SIG%s", signame(ap[1], 1));
ap += 2;
argcount -= 2;
c = ',';
} else if (strcmp(sys_name, "ptrace") == 0 && argcount >= 1) {
putchar('(');
if (strcmp(emul->name, "linux") == 0) {
if (*ap >= 0 && *ap <=
sizeof(linux_ptrace_ops) /
sizeof(linux_ptrace_ops[0]))
(void)printf("%s",
linux_ptrace_ops[*ap]);
else
output_long((long)*ap, 1);
} else {
if (*ap >= 0 && *ap <=
sizeof(ptrace_ops) / sizeof(ptrace_ops[0]))
(void)printf("%s", ptrace_ops[*ap]);
else
output_long((long)*ap, 1);
}
ap++;
argcount--;
c = ',';
}
while (argcount > 0) {
putchar(c);
output_long((long)*ap, (decimal || *ap <= 9));
ap++;
argcount--;
c = ',';
}
(void)putchar(')');
}
(void)putchar('\n');
}
void
ktrsysret(ktr, len)
struct ktr_sysret *ktr;
int len;
{
const struct emulation *emul;
int error = ktr->ktr_error;
int code = ktr->ktr_code;
if (emul_changed) {
/* In order to get system call name right in execve return */
emul = prev_emul;
emul_changed = 0;
} else
emul = cur_emul;
if ((code >= emul->nsysnames || code < 0 || plain > 1)
&& (mach_traps_dispatch(&code, &emul) == 0))
(void)printf("[%d] ", code);
else
(void)printf("%s ", emul->sysnames[code]);
switch (error) {
case 0:
rprint(ktr->ktr_retval);
if (len > offsetof(struct ktr_sysret, ktr_retval_1) &&
ktr->ktr_retval_1 != 0) {
(void)printf(", ");
rprint(ktr->ktr_retval_1);
}
break;
default:
eprint(error);
break;
}
(void)putchar('\n');
}
void
rprint(register_t ret)
{
if (!plain) {
(void)printf("%ld", (long)ret);
if (ret < 0 || ret > 9)
(void)printf("/%#lx", (long)ret);
} else {
if (decimal || ret <= 9)
(void)printf("%ld", (long)ret);
else
(void)printf("%#lx", (long)ret);
}
}
/*
* We print the original emulation's error numerically, but we
* translate it to netbsd to print it symbolically.
*/
void
eprint(e)
int e;
{
int i = e;
if (cur_emul->errnomap) {
/* No remapping for ERESTART and EJUSTRETURN */
/* Kludge for linux that has negative error numbers */
if (cur_emul->errnomap[2] > 0 && e < 0)
goto normal;
for (i = 0; i < cur_emul->nerrnomap; i++)
if (e == cur_emul->errnomap[i])
break;
if (i == cur_emul->nerrnomap) {
printf("-1 unknown errno %d", e);
return;
}
}
normal:
switch (i) {
case ERESTART:
(void)printf("RESTART");
break;
case EJUSTRETURN:
(void)printf("JUSTRETURN");
break;
default:
(void)printf("-1 errno %d", e);
if (!plain)
(void)printf(" %s", strerror(i));
}
}
void
ktrnamei(cp, len)
char *cp;
int len;
{
(void)printf("\"%.*s\"\n", len, cp);
}
void
ktremul(name, len, bufsize)
char *name;
int len, bufsize;
{
if (len >= bufsize)
len = bufsize - 1;
name[len] = '\0';
setemul(name, ktr_header.ktr_pid, 1);
emul_changed = 1;
(void)printf("\"%s\"\n", name);
}
static void
hexdump_buf(vdp, datalen, word_sz)
const void *vdp;
int datalen;
int word_sz;
{
const char hex[] = "0123456789abcdef";
char chars[16];
char bytes[16 * 3 + 4];
const unsigned char *dp = vdp;
const unsigned char *datalim = dp + datalen;
const unsigned char *line_end;
int off, l, c;
char *cp, *bp;
int divmask = word_sz - 1; /* block size in bytes */
int gdelim = 3; /* gap between blocks */
int bsize = 2; /* increment for each byte */
int width;
#if _BYTE_ORDER == _LITTLE_ENDIAN
int bswap = word_sz - 1;
#else
#define bswap 0
#endif
switch (word_sz) {
case 2:
gdelim = 2;
break;
case 1:
divmask = 7;
bsize = 3;
gdelim = 1;
break;
default:
break;
}
width = 16 * bsize + (16 / (divmask + 1)) * gdelim;
if (word_size != 1)
width += 2;
for (off = 0; dp < datalim; off += l) {
memset(bytes, ' ', sizeof bytes);
line_end = dp + 16;
if (line_end > datalim)
line_end = datalim;
for (l = 0, bp = bytes, cp = chars; dp < line_end; l++) {
c = *dp++;
if ((l & divmask) == 0)
bp += gdelim;
bp[(l ^ bswap) * bsize] = hex[c >> 4];
bp[(l ^ bswap) * bsize + 1] = hex[c & 0xf];
*cp++ = isgraph(c) ? c : '.';
};
printf("\t%-5.3x%.*s%.*s\n", off, width, bytes, l, chars);
}
}
static void
visdump_buf(const void *vdp, int datalen, int col)
{
const unsigned char *dp = vdp;
char *cp;
int width;
char visbuf[5];
static int screenwidth = 0;
if (screenwidth == 0) {
struct winsize ws;
if (!plain && ioctl(fileno(stderr), TIOCGWINSZ, &ws) != -1 &&
ws.ws_col > 8)
screenwidth = ws.ws_col;
else
screenwidth = 80;
}
(void)printf("\"");
col++;
for (; datalen > 0; datalen--, dp++) {
(void)svis(visbuf, *dp, VIS_CSTYLE,
datalen > 1 ? *(dp + 1) : 0, "\"");
cp = visbuf;
/*
* Keep track of printables and
* space chars (like fold(1)).
*/
if (col == 0) {
(void)putchar('\t');
col = 8;
}
switch(*cp) {
case '\n':
col = 0;
(void)putchar('\n');
continue;
case '\t':
width = 8 - (col & 07);
break;
default:
width = strlen(cp);
}
if (col + width > (screenwidth - 2)) {
(void)printf("\\\n\t");
col = 8;
}
col += width;
do {
(void)putchar(*cp++);
} while (*cp);
}
if (col == 0)
(void)printf(" ");
(void)printf("\"\n");
}
void
ktrgenio(ktr, len)
struct ktr_genio *ktr;
int len;
{
int datalen = len - sizeof (struct ktr_genio);
char *dp = (char *)ktr + sizeof (struct ktr_genio);
printf("fd %d %s %d bytes\n", ktr->ktr_fd,
ktr->ktr_rw == UIO_READ ? "read" : "wrote", datalen);
if (maxdata == 0)
return;
if (maxdata > 0 && datalen > maxdata)
datalen = maxdata;
if (word_size) {
hexdump_buf(dp, datalen, word_size);
return;
}
(void)printf(" ");
visdump_buf(dp, datalen, 7);
}
void
ktrpsig(v, len)
void *v;
int len;
{
int signo, first;
struct {
struct ktr_psig ps;
siginfo_t si;
} *psig = v;
siginfo_t *si = &psig->si;
const char *code;
(void)printf("SIG%s ", signame(psig->ps.signo, 0));
if (psig->ps.action == SIG_DFL)
(void)printf("SIG_DFL");
else {
(void)printf("caught handler=%p mask=(", psig->ps.action);
first = 1;
for (signo = 1; signo < NSIG; signo++) {
if (sigismember(&psig->ps.mask, signo)) {
if (first)
first = 0;
else
(void)printf(",");
(void)printf("%d", signo);
}
}
(void)printf(")");
}
switch (len) {
case sizeof(struct ktr_psig):
if (psig->ps.code)
printf(" code=0x%x", psig->ps.code);
printf(psig->ps.action == SIG_DFL ? "\n" : ")\n");
return;
case sizeof(*psig):
if (si->si_code == 0) {
printf(": code=SI_USER sent by pid=%d, uid=%d)\n",
si->si_pid, si->si_uid);
return;
}
if (si->si_code < 0) {
switch (si->si_code) {
case SI_TIMER:
printf(": code=SI_TIMER sigval %p)\n",
si->si_sigval.sival_ptr);
return;
case SI_QUEUE:
code = "SI_QUEUE";
break;
case SI_ASYNCIO:
code = "SI_ASYNCIO";
break;
case SI_MESGQ:
code = "SI_MESGQ";
break;
default:
code = NULL;
break;
}
if (code)
printf(": code=%s unimplemented)\n", code);
else
printf(": code=%d unimplemented)\n",
si->si_code);
return;
}
code = siginfocodename(si->si_signo, si->si_code);
switch (si->si_signo) {
case SIGCHLD:
printf(": code=%s child pid=%d, uid=%d, "
" status=%u, utime=%lu, stime=%lu)\n",
code, si->si_pid,
si->si_uid, si->si_status,
(unsigned long) si->si_utime,
(unsigned long) si->si_stime);
return;
case SIGILL:
case SIGFPE:
case SIGSEGV:
case SIGBUS:
case SIGTRAP:
printf(": code=%s, addr=%p, trap=%d)\n",
code, si->si_addr, si->si_trap);
return;
case SIGIO:
printf(": code=%s, fd=%d, band=%lx)\n",
code, si->si_fd, si->si_band);
return;
default:
printf(": code=%s, errno=%d)\n",
code, si->si_errno);
return;
}
/*NOTREACHED*/
default:
warnx("Unhandled size %d for ktrpsig\n", len);
break;
}
}
void
ktrcsw(cs)
struct ktr_csw *cs;
{
(void)printf("%s %s\n", cs->out ? "stop" : "resume",
cs->user ? "user" : "kernel");
}
void
ktruser(usr, len)
struct ktr_user *usr;
int len;
{
int i;
unsigned char *dta;
printf("\"%.*s: %d, ", KTR_USER_MAXIDLEN, usr->ktr_id, len);
dta = (unsigned char *)usr;
for(i=sizeof(struct ktr_user); i < len; i++)
printf("%02x", (unsigned int) dta[i]);
printf("\"\n");
}
void
ktrmmsg(mmsg, len)
struct ktr_mmsg *mmsg;
int len;
{
const char *service_name;
char *reply;
int id;
id = mmsg->ktr_id;
if ((id / 100) % 2) { /* Message reply */
reply = " reply";
id -= 100;
} else {
reply = "";
}
if ((service_name = mach_service_name(id)) != NULL)
printf("%s%s [%d]\n", service_name, reply, mmsg->ktr_id);
else
printf("unknown service%s [%d]\n", reply, mmsg->ktr_id);
hexdump_buf(mmsg, len, word_size ? word_size : 4);
}
void
ktrmool(mool, len)
struct ktr_mool *mool;
int len;
{
size_t size = mool->size;
printf("%ld/0x%lx bytes at %p\n",
(u_long)size, (u_long)size, mool->uaddr);
mool++;
hexdump_buf(mool, size, word_size ? word_size : 4);
}
static const char *
signame(long sig, int xlat)
{
static char buf[64];
if (sig == 0)
return " 0";
else if (sig < 0 || sig >= NSIG) {
(void)snprintf(buf, sizeof(buf), "*unknown %ld*", sig);
return buf;
} else
return sys_signame[(xlat && cur_emul->signalmap != NULL) ?
cur_emul->signalmap[sig] : sig];
}
void
usage()
{
(void)fprintf(stderr, "usage: kdump [-dlNnRT] [-e emulation] "
"[-f file] [-m maxdata] [-p pid]\n [-t trstr] "
"[-x | -X size] [file]\n");
exit(1);
}