Files
libguestfs/lib/inspect.c

134 lines
3.4 KiB
C

/* libguestfs
* Copyright (C) 2010-2012 Red Hat Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <sys/stat.h>
#include <libintl.h>
#include <assert.h>
#ifdef HAVE_ENDIAN_H
#include <endian.h>
#endif
#include "ignore-value.h"
#include "xstrtol.h"
#include "guestfs.h"
#include "guestfs-internal.h"
#include "guestfs-internal-actions.h"
/**
* Download a guest file to a local temporary file. The file is
* cached in the temporary directory, and is not downloaded again.
*
* The name of the temporary (downloaded) file is returned. The
* caller must free the pointer, but does I<not> need to delete the
* temporary file. It will be deleted when the handle is closed.
*
* Refuse to download the guest file if it is larger than C<max_size>.
* On this and other errors, C<NULL> is returned.
*
* There is actually one cache per C<struct inspect_fs *> in order to
* handle the case of multiple roots.
*/
char *
guestfs_int_download_to_tmp (guestfs_h *g,
const char *filename,
const char *basename, uint64_t max_size)
{
char *r;
int fd;
char devfd[32];
int64_t size;
if (asprintf (&r, "%s/%s", g->tmpdir, basename) == -1) {
perrorf (g, "asprintf");
return NULL;
}
/* Check size of remote file. */
size = guestfs_filesize (g, filename);
if (size == -1)
/* guestfs_filesize failed and has already set error in handle */
goto error;
if ((uint64_t) size > max_size) {
error (g, _("size of %s is unreasonably large (%" PRIi64 " bytes)"),
filename, size);
goto error;
}
fd = open (r, O_WRONLY|O_CREAT|O_TRUNC|O_NOCTTY|O_CLOEXEC, 0600);
if (fd == -1) {
perrorf (g, "open: %s", r);
goto error;
}
snprintf (devfd, sizeof devfd, "/dev/fd/%d", fd);
if (guestfs_download (g, filename, devfd) == -1) {
unlink (r);
close (fd);
goto error;
}
if (close (fd) == -1) {
perrorf (g, "close: %s", r);
unlink (r);
goto error;
}
return r;
error:
free (r);
return NULL;
}
/* Parse small, unsigned ints, as used in version numbers. */
int
guestfs_int_parse_unsigned_int (guestfs_h *g, const char *str)
{
long ret;
const int r = xstrtol (str, NULL, 10, &ret, "");
if (r != LONGINT_OK) {
error (g, _("could not parse integer in version number: %s"), str);
return -1;
}
return ret;
}
/* Like parse_unsigned_int, but ignore trailing stuff. */
int
guestfs_int_parse_unsigned_int_ignore_trailing (guestfs_h *g, const char *str)
{
long ret;
const int r = xstrtol (str, NULL, 10, &ret, NULL);
if (r != LONGINT_OK) {
error (g, _("could not parse integer in version number: %s"), str);
return -1;
}
return ret;
}