tests: Regression test for RHBZ#701814.

This commit adds a tests/xml directory, and an LD_PRELOAD module which
can fake arbitrary libvirt XML from an external file (and is therefore
a much more flexible test than using the libvirt test:// driver
alone).

Also added is one regression test for:
https://bugzilla.redhat.com/show_bug.cgi?id=701814

Loading the given libvirt XML using Sys::Guestfs::Lib::open_guest
used to fail with the error:

  format parameter is empty or contains disallowed characters at /home/rjones/d/libguestfs/perl/blib/lib/Sys/Guestfs/Lib.pm line 256.

Thanks to Tom Horsley for supplying the test data.

1 files changed, 87 insertions, 0 deletions

diff --git a/tests/xml/fake_libvirt_xml.c b/tests/xml/fake_libvirt_xml.c
new file mode 100644
index 00000000..61192413
--- /dev/null
+++ b/tests/xml/fake_libvirt_xml.c
@@ -0,0 +1,87 @@
+/* libguestfs
+ * Copyright (C) 2012 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <libvirt/libvirt.h>
+
+char *
+virDomainGetXMLDesc (virDomainPtr dom, unsigned int flags)
+{
+  const char *path;
+  int fd;
+  struct stat statbuf;
+  char *buf, *p;
+  size_t n;
+  ssize_t r;
+
+  path = getenv ("FAKE_LIBVIRT_XML");
+
+  if (!path) {
+    fprintf (stderr, "environment variable FAKE_LIBVIRT_XML is not set\n");
+    _exit (1);
+  }
+
+  fprintf (stderr,
+           "fake_libvirt_xml: returning fake libvirt XML from %s\n", path);
+
+  fd = open (path, O_RDONLY | O_CLOEXEC);
+  if (fd == -1) {
+    perror (path);
+    _exit (1);
+  }
+
+  if (fstat (fd, &statbuf) == -1) {
+    perror ("fstat");
+    _exit (1);
+  }
+
+  buf = malloc (statbuf.st_size + 1);
+  if (buf == NULL) {
+    perror ("malloc");
+    _exit (1);
+  }
+
+  for (n = 0, p = buf; n < statbuf.st_size; ++n) {
+    r = read (fd, p, statbuf.st_size - n);
+    if (r == -1) {
+      perror ("read");
+      _exit (1);
+    }
+    if (r == 0)
+      break;
+    n += r;
+    p += r;
+  }
+
+  *p = '\0';
+
+  if (close (fd) == -1) {
+    perror ("close");
+    _exit (1);
+  }
+
+  return buf;                   /* caller frees */
+}