diff options
Diffstat (limited to 'fish/virt.c')
| -rw-r--r-- | fish/virt.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/fish/virt.c b/fish/virt.c new file mode 100644 index 00000000..9c4ce1ad --- /dev/null +++ b/fish/virt.c @@ -0,0 +1,191 @@ +/* guestfish - the filesystem interactive shell + * 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. + */ + +#include <config.h> + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <assert.h> + +#include <libvirt/libvirt.h> +#include <libvirt/virterror.h> + +#include <libxml/xpath.h> +#include <libxml/parser.h> +#include <libxml/tree.h> + +#include "fish.h" + +static int add_drives_from_node_set (xmlDocPtr doc, xmlNodeSetPtr nodes); + +/* Implements the guts of the '-d' option. + * + * Note that we have to observe the '--ro' flag in two respects: by + * adding the drives read-only if the flag is set, and by restricting + * guests to shut down ones unless '--ro' is set. + * + * Returns the number of drives added (> 0), or -1 for failure. + */ +int +add_libvirt_drives (const char *guest) +{ + static int initialized = 0; + if (!initialized) { + initialized = 1; + + if (virInitialize () == -1) + return -1; + + xmlInitParser (); + LIBXML_TEST_VERSION; + } + + int r = -1, nr_added = 0; + virErrorPtr err; + virConnectPtr conn = NULL; + virDomainPtr dom = NULL; + xmlDocPtr doc = NULL; + xmlXPathContextPtr xpathCtx = NULL; + xmlXPathObjectPtr xpathObj = NULL; + char *xml = NULL; + + /* Connect to libvirt, find the domain. */ + conn = virConnectOpenReadOnly (libvirt_uri); + if (!conn) { + err = virGetLastError (); + fprintf (stderr, _("guestfish: could not connect to libvirt (code %d, domain %d): %s\n"), + err->code, err->domain, err->message); + goto cleanup; + } + + dom = virDomainLookupByName (conn, guest); + if (!dom) { + err = virConnGetLastError (conn); + fprintf (stderr, _("guestfish: no libvirt domain called '%s': %s\n"), + guest, err->message); + goto cleanup; + } + if (!read_only) { + virDomainInfo info; + if (virDomainGetInfo (dom, &info) == -1) { + err = virConnGetLastError (conn); + fprintf (stderr, _("guestfish: error getting domain info about '%s': %s\n"), + guest, err->message); + goto cleanup; + } + if (info.state != VIR_DOMAIN_SHUTOFF) { + fprintf (stderr, _("guestfish: error: '%s' is a live virtual machine.\nYou must use '--ro' because write access to a running virtual machine can\ncause disk corruption.\n"), + guest); + goto cleanup; + } + } + + /* Domain XML. */ + xml = virDomainGetXMLDesc (dom, 0); + + if (!xml) { + err = virConnGetLastError (conn); + fprintf (stderr, _("guestfish: error reading libvirt XML information about '%s': %s\n"), + guest, err->message); + goto cleanup; + } + + /* Now the horrible task of parsing out the fields we need from the XML. + * http://www.xmlsoft.org/examples/xpath1.c + */ + doc = xmlParseMemory (xml, strlen (xml)); + if (doc == NULL) { + fprintf (stderr, _("guestfish: unable to parse XML information returned by libvirt\n")); + goto cleanup; + } + + xpathCtx = xmlXPathNewContext (doc); + if (xpathCtx == NULL) { + fprintf (stderr, _("guestfish: unable to create new XPath context\n")); + goto cleanup; + } + + xpathObj = xmlXPathEvalExpression (BAD_CAST "//devices/disk/source/@dev", + xpathCtx); + if (xpathObj == NULL) { + fprintf (stderr, _("guestfish: unable to evaluate XPath expression\n")); + goto cleanup; + } + + nr_added += add_drives_from_node_set (doc, xpathObj->nodesetval); + + xmlXPathFreeObject (xpathObj); xpathObj = NULL; + + xpathObj = xmlXPathEvalExpression (BAD_CAST "//devices/disk/source/@file", + xpathCtx); + if (xpathObj == NULL) { + fprintf (stderr, _("guestfish: unable to evaluate XPath expression\n")); + goto cleanup; + } + + nr_added += add_drives_from_node_set (doc, xpathObj->nodesetval); + + if (nr_added == 0) { + fprintf (stderr, _("guestfish: libvirt domain '%s' has no disks\n"), + guest); + goto cleanup; + } + + /* Successful. */ + r = nr_added; + +cleanup: + free (xml); + if (xpathObj) xmlXPathFreeObject (xpathObj); + if (xpathCtx) xmlXPathFreeContext (xpathCtx); + if (doc) xmlFreeDoc (doc); + if (dom) virDomainFree (dom); + if (conn) virConnectClose (conn); + + return r; +} + +static int +add_drives_from_node_set (xmlDocPtr doc, xmlNodeSetPtr nodes) +{ + if (!nodes) + return 0; + + int i; + + for (i = 0; i < nodes->nodeNr; ++i) { + assert (nodes->nodeTab[i]); + assert (nodes->nodeTab[i]->type == XML_ATTRIBUTE_NODE); + xmlAttrPtr attr = (xmlAttrPtr) nodes->nodeTab[i]; + + char *device = (char *) xmlNodeListGetString (doc, attr->children, 1); + + int r; + if (!read_only) + r = guestfs_add_drive (g, device); + else + r = guestfs_add_drive_ro (g, device); + if (r == -1) + exit (EXIT_FAILURE); + + xmlFree (device); + } + + return nodes->nodeNr; +} |