--- /dev/null
+#!/usr/bin/perl
+# Copyright (C) 2010 Red Hat Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+# Test that 2 simultaneous launches in a clean cache directory will both succeed
+
+use strict;
+use warnings;
+
+use File::Temp qw(tempdir);
+use POSIX;
+
+use Sys::Guestfs;
+
+# Use a temporary TMPDIR to ensure it's clean
+my $tmpdir = tempdir (CLEANUP => 1);
+$ENV{TMPDIR} = $tmpdir;
+
+my $testimg = $tmpdir.'/test.img';
+system ("touch $testimg");
+
+my $pid = fork();
+die ("fork failed: $!") if ($pid < 0);
+
+if ($pid == 0) {
+ my $g = Sys::Guestfs->new ();
+ $g->add_drive ($testimg);
+ $g->launch ();
+ _exit (0);
+}
+
+my $g = Sys::Guestfs->new ();
+$g->add_drive ($testimg);
+$g->launch ();
+$g = undef;
+
+waitpid ($pid, 0) or die ("waitpid: $!");
+die ("child failed") unless ($? == 0);
+
+# Check that only 1 temporary cache directory was created
+my $dh;
+opendir ($dh, $tmpdir) or die ("Failed to open $tmpdir: $!");
+my @cachedirs = grep { /^guestfs\./ } readdir ($dh);
+closedir ($dh) or die ("Failed to close $tmpdir: $!");
+
+my $ncachedirs = scalar(@cachedirs);
+die ("Expected 1 cachedir, found $ncachedirs") unless ($ncachedirs == 1);
#include <config.h>
+#include <errno.h>
+#include <dirent.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
{
const char *tmpdir = guestfs_tmpdir ();
- size_t len = strlen (tmpdir) + strlen (checksum) + 2;
+ size_t len = strlen (tmpdir) + strlen (checksum) + 10;
char cachedir[len];
- snprintf (cachedir, len, "%s/%s", tmpdir, checksum);
+ snprintf (cachedir, len, "%s/guestfs.%s", tmpdir, checksum);
/* Touch the directory to prevent it being deleting in a rare race
* between us doing the checks and a tmp cleaner running. Note this
guestfs___print_timestamped_message (g, "begin building supermin appliance");
const char *tmpdir = guestfs_tmpdir ();
- size_t cdlen = strlen (tmpdir) + strlen (checksum) + 2;
- char cachedir[cdlen];
- snprintf (cachedir, cdlen, "%s/%s", tmpdir, checksum);
- /* Don't worry about this failing, because the
- * febootstrap-supermin-helper command will fail if the directory
- * doesn't exist. Note the directory might already exist, eg. if a
- * tmp cleaner has removed the existing appliance but not the
- * directory itself.
- */
- (void) mkdir (cachedir, 0755);
+ size_t tmpcdlen = strlen (tmpdir) + 16;
+ char tmpcd[tmpcdlen];
+ snprintf (tmpcd, tmpcdlen, "%s/guestfs.XXXXXX", tmpdir);
+
+ if (NULL == mkdtemp (tmpcd)) {
+ error (g, _("failed to create temporary cache directory: %m"));
+ return -1;
+ }
if (g->verbose)
guestfs___print_timestamped_message (g, "run febootstrap-supermin-helper");
- int r = run_supermin_helper (g, supermin_path, cachedir, cdlen);
+ int r = run_supermin_helper (g, supermin_path, tmpcd, tmpcdlen);
if (r == -1)
return -1;
if (g->verbose)
guestfs___print_timestamped_message (g, "finished building supermin appliance");
+ size_t cdlen = strlen (tmpdir) + strlen (checksum) + 10;
+ char cachedir[cdlen];
+ snprintf (cachedir, cdlen, "%s/guestfs.%s", tmpdir, checksum);
+
+ /* Make the temporary directory world readable */
+ if (chmod (tmpcd, 0755) == -1) {
+ error (g, "chmod %s: %m", tmpcd);
+ }
+
+ /* Try to rename the temporary directory to its non-temporary name */
+ if (rename (tmpcd, cachedir) == -1) {
+ /* If the cache directory now exists, we may have been racing with another
+ * libguestfs process. Check the new directory and use it if it's valid. */
+ if (errno == ENOTEMPTY || errno == EEXIST) {
+ /* Appliance cache consists of 2 files and a symlink in the cache
+ * directory. Delete them first. */
+ DIR *dir = opendir (tmpcd);
+ if (dir == NULL) {
+ error (g, "opendir %s: %m", tmpcd);
+ return -1;
+ }
+
+ int fd = dirfd (dir);
+ if (fd == -1) {
+ error (g, "dirfd: %m");
+ closedir (dir);
+ return -1;
+ }
+
+ struct dirent *dirent;
+ for (;;) {
+ errno = 0;
+ dirent = readdir (dir);
+
+ if (dirent == NULL) {
+ break;
+ }
+
+ /* Check that dirent is a file so we don't try to delete . and .. */
+ struct stat st;
+ if (fstatat (fd, dirent->d_name, &st, AT_SYMLINK_NOFOLLOW) == -1) {
+ error (g, "fstatat %s: %m", dirent->d_name);
+ return -1;
+ }
+
+ if (!S_ISDIR(st.st_mode)) {
+ if (unlinkat (fd, dirent->d_name, 0) == -1) {
+ error (g, "unlinkat %s: %m", dirent->d_name);
+ closedir (dir);
+ return -1;
+ }
+ }
+ }
+
+ if (errno != 0) {
+ error (g, "readdir %s: %m", tmpcd);
+ closedir (dir);
+ return -1;
+ }
+
+ closedir (dir);
+
+ /* Delete the temporary cache directory itself. */
+ if (rmdir (tmpcd) == -1) {
+ error (g, "rmdir %s: %m", tmpcd);
+ return -1;
+ }
+
+ /* Check the new cache directory, and return it if valid */
+ return check_for_cached_appliance (g, supermin_path, checksum,
+ kernel, initrd, appliance);
+ }
+
+ else {
+ error (g, _("error renaming temporary cache directory: %m"));
+ return -1;
+ }
+ }
+
*kernel = safe_malloc (g, cdlen + 8 /* / + "kernel" + \0 */);
*initrd = safe_malloc (g, cdlen + 8 /* / + "initrd" + \0 */);
*appliance = safe_malloc (g, cdlen + 6 /* / + "root" + \0 */);
git.annexia.org / libguestfs.git / commitdiff