From: Anthony PERARD <anthony.perard@xxxxxxxxxx>
QMP stands for QEMU Monitor Protocol and it is used to query information
from QEMU or to control QEMU.
This implementation will ask QEMU the list of chardevice and store the
path to serial0 in xenstored. So we will be able to use xl console with
QEMU upstream.
In order to connect to the QMP server, a socket file is created in
/var/run/xen/qmp-$(domid).
Signed-off-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>
---
Change v2->v3:
- Use of a timeout when wait for a reply from the server.
- Use of a command list, a list of pair "command" + callback. It's associated
with an enum.
- Introduce libxl__qmp_initializations that will ask of all informations need
through QMP. (It's just a rename of libxl__qmp_get_serial_console_path from
the previous patch.)
Change v1->v2:
- Introduction of libxl_run_dir_path(), should maybe be in another patch.
- Add a new static function qmp_synchronous_send that wait the answer from
the server.
- QMP is know use only inside libxl, so only one command is send through the
socket and after, the connection is closed.
Config.mk | 1 +
config/StdGNU.mk | 2 +
tools/libxl/Makefile | 4 +
tools/libxl/libxl.h | 1 +
tools/libxl/libxl_create.c | 4 +
tools/libxl/libxl_dm.c | 6 +
tools/libxl/libxl_paths.c | 4 +
tools/libxl/libxl_qmp.c | 980 ++++++++++++++++++++++++++++++++++++++++++++
tools/libxl/libxl_qmp.h | 35 ++
9 files changed, 1037 insertions(+), 0 deletions(-)
create mode 100644 tools/libxl/libxl_qmp.c
create mode 100644 tools/libxl/libxl_qmp.h
diff --git a/Config.mk b/Config.mk
index aa681ae..8b11cd8 100644
--- a/Config.mk
+++ b/Config.mk
@@ -133,6 +133,7 @@ define buildmakevars2file-closure
echo "XEN_CONFIG_DIR=\"$(XEN_CONFIG_DIR)\"" >> $(1).tmp; \
echo "XEN_SCRIPT_DIR=\"$(XEN_SCRIPT_DIR)\"" >> $(1).tmp; \
echo "XEN_LOCK_DIR=\"$(XEN_LOCK_DIR)\"" >> $(1).tmp; \
+ echo "XEN_RUN_DIR=\"$(XEN_RUN_DIR)\"" >> $(1).tmp; \
if ! cmp $(1).tmp $(1); then mv -f $(1).tmp $(1); fi
endef
diff --git a/config/StdGNU.mk b/config/StdGNU.mk
index 25aeb4d..68fa226 100644
--- a/config/StdGNU.mk
+++ b/config/StdGNU.mk
@@ -52,9 +52,11 @@ PRIVATE_BINDIR = $(PRIVATE_PREFIX)/bin
ifeq ($(PREFIX),/usr)
CONFIG_DIR = /etc
XEN_LOCK_DIR = /var/lock
+XEN_RUN_DIR = /var/run/xen
else
CONFIG_DIR = $(PREFIX)/etc
XEN_LOCK_DIR = $(PREFIX)/var/lock
+XEN_RUN_DIR = $(PREFIX)/var/run/xen
endif
SYSCONFIG_DIR = $(CONFIG_DIR)/$(CONFIG_LEAF_DIR)
diff --git a/tools/libxl/Makefile b/tools/libxl/Makefile
index 84ab76f..be5445d 100644
--- a/tools/libxl/Makefile
+++ b/tools/libxl/Makefile
@@ -32,6 +32,9 @@ endif
LIBXL_OBJS-$(CONFIG_X86) += libxl_cpuid.o
LIBXL_OBJS-$(CONFIG_IA64) += libxl_nocpuid.o
+LIBXL_OBJS-y += libxl_qmp.o
+LIBXL_LIBS += -lyajl
+
LIBXL_OBJS = flexarray.o libxl.o libxl_create.o libxl_dm.o libxl_pci.o \
libxl_dom.o libxl_exec.o libxl_xshelp.o libxl_device.o \
libxl_internal.o libxl_utils.o libxl_uuid.o
$(LIBXL_OBJS-y)
@@ -115,6 +118,7 @@ install: all
$(INSTALL_DIR) $(DESTDIR)$(LIBDIR)
$(INSTALL_DIR) $(DESTDIR)$(INCLUDEDIR)
$(INSTALL_DIR) $(DESTDIR)$(BASH_COMPLETION_DIR)
+ $(INSTALL_DIR) $(DESTDIR)$(XEN_RUN_DIR)
$(INSTALL_PROG) xl $(DESTDIR)$(SBINDIR)
$(INSTALL_PROG) libxenlight.so.$(MAJOR).$(MINOR) $(DESTDIR)$(LIBDIR)
ln -sf libxenlight.so.$(MAJOR).$(MINOR)
$(DESTDIR)$(LIBDIR)/libxenlight.so.$(MAJOR)
diff --git a/tools/libxl/libxl.h b/tools/libxl/libxl.h
index b0471c0..c3bbe87 100644
--- a/tools/libxl/libxl.h
+++ b/tools/libxl/libxl.h
@@ -518,6 +518,7 @@ const char *libxl_xenfirmwaredir_path(void);
const char *libxl_xen_config_dir_path(void);
const char *libxl_xen_script_dir_path(void);
const char *libxl_lock_dir_path(void);
+const char *libxl_run_dir_path(void);
#endif /* LIBXL_H */
diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
index 91e2414..e818faf 100644
--- a/tools/libxl/libxl_create.c
+++ b/tools/libxl/libxl_create.c
@@ -30,6 +30,7 @@
#include "libxl_utils.h"
#include "libxl_internal.h"
#include "flexarray.h"
+#include "libxl_qmp.h"
void libxl_domain_config_destroy(libxl_domain_config *d_config)
{
@@ -514,6 +515,9 @@ static int do_domain_create(libxl__gc *gc,
libxl_domain_config *d_config,
}
if (dm_starting) {
+ if (dm_info->device_model_version ==
LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN) {
+ libxl__qmp_initializations(ctx, domid);
+ }
ret = libxl__confirm_device_model_startup(gc, dm_starting);
if (ret < 0) {
LIBXL__LOG(ctx, LIBXL__LOG_ERROR,
diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
index 5e80bc8..094226d 100644
--- a/tools/libxl/libxl_dm.c
+++ b/tools/libxl/libxl_dm.c
@@ -245,6 +245,12 @@ static char **
libxl__build_device_model_args_new(libxl__gc *gc,
flexarray_vappend(dm_args, dm,
"-xen-domid", libxl__sprintf(gc, "%d", info->domid),
NULL);
+ flexarray_append(dm_args, "-qmp");
+ flexarray_append(dm_args,
+ libxl__sprintf(gc, "unix:%s/qmp-%d,server,nowait",
+ libxl_run_dir_path(),
+ info->domid));
+
if (info->type == LIBXL_DOMAIN_TYPE_PV) {
flexarray_append(dm_args, "-xen-attach");
}
diff --git a/tools/libxl/libxl_paths.c b/tools/libxl/libxl_paths.c
index 9c2bd06..ec940e3 100644
--- a/tools/libxl/libxl_paths.c
+++ b/tools/libxl/libxl_paths.c
@@ -64,3 +64,7 @@ const char *libxl_lock_dir_path(void)
{
return XEN_LOCK_DIR;
}
+const char *libxl_run_dir_path(void)
+{
+ return XEN_RUN_DIR;
+}
diff --git a/tools/libxl/libxl_qmp.c b/tools/libxl/libxl_qmp.c
new file mode 100644
index 0000000..061eea6
--- /dev/null
+++ b/tools/libxl/libxl_qmp.c
@@ -0,0 +1,980 @@
+/*
+ * Copyright (C) 2011 Citrix Ltd.
+ * Author Anthony PERARD <anthony.perard@xxxxxxxxxx>
+ *
+ * This program 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; version 2.1 only. with the special
+ * exception on linking described in file LICENSE.
+ *
+ * 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 Lesser General Public License for more details.
+ */
+
+/*
+ * This file implement a client for QMP (QEMU Monitor Protocol). For the
+ * Specification, see in the QEMU repository.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/un.h>
+#include <sys/queue.h>
+
+#include <yajl/yajl_parse.h>
+#include <yajl/yajl_gen.h>
+
+#include "libxl_internal.h"
+#include "flexarray.h"
+#include "libxl_qmp.h"
+
+/* #define DEBUG_ANSWER */
+/* #define DEBUG_RECEIVE */
+
+/*
+ * json_object types
+ */
+
+typedef struct json_object json_object;
+typedef struct json_map_node json_map_node;
+typedef enum node_type node_type_e;
+
+enum node_type {
+ JSON_ERROR,
+ JSON_NULL,
+ JSON_BOOL,
+ JSON_INTEGER,
+ JSON_DOUBLE,
+ JSON_STRING,
+ JSON_MAP,
+ JSON_ARRAY
+};
+
+struct json_object {
+ node_type_e type;
+ union {
+ bool boolean;
+ long integer;
+ double floating;
+ const char *string;
+ /* List of json_object */
+ flexarray_t *array;
+ /* List of json_map_node */
+ flexarray_t *map;
+ } u;
+ json_object *parent;
+};
+
+struct json_map_node {
+ const char *map_key;
+ json_object *obj;
+};
+
+/*
+ * QMP types & constant
+ */
+
+typedef int (*qmp_callback_t)(libxl__qmp_handler *qmp, const json_object
*tree);
+
+typedef enum message_type {
+ QMP_ANY,
+ QMP_QMP,
+ QMP_RETURN,
+ QMP_ERROR,
+ QMP_EVENT
+} message_type_e;
+
+struct {
+ const char *name;
+ message_type_e type;
+} member_name_to_message_type[] = {
+ { "QMP", QMP_QMP },
+ { "return", QMP_RETURN },
+ { "error", QMP_ERROR },
+ { "event", QMP_EVENT },
+ { "", QMP_ANY },
+};
+
+typedef struct callback_id_pair {
+ int id;
+ qmp_callback_t callback;
+ SIMPLEQ_ENTRY(callback_id_pair) next;
+} callback_id_pair;
+
+struct libxl__qmp_handler {
+ struct sockaddr_un addr;
+ int qmp_fd;
+ bool connected;
+ /* this will be used by the synchronous send, so we know
+ * when we can stop and close the socket
+ */
+ int wait_for_id;
+
+ unsigned char *buffer;
+ yajl_handle hand;
+
+ json_object *head;
+ json_object *current;
+
+ libxl_ctx *ctx;
+ uint32_t domid;
+
+ int last_id_used;
+ SIMPLEQ_HEAD(callback_list, callback_id_pair) callback_list;
+#ifdef DEBUG_ANSWER
+ yajl_gen g;
+#endif
+};
+
+static int qmp_send(libxl__qmp_handler *qmp, const char *cmd, qmp_callback_t
callback);
+static int qmp_synchronous_send(libxl__qmp_handler *qmp, const char *cmd,
qmp_callback_t callback, int timeout);
+
+static const size_t QMP_RECEIVE_BUFFER_SIZE = 65536;
+static const int QMP_SOCKET_CONNECT_TIMEOUT = 5;
+
+/*
+ * QMP commands
+ */
+
+static int register_serial0_chardev_callback(libxl__qmp_handler *qmp, const
json_object *tree);
+
+struct qmp_command_list_t {
+ const char *cmd;
+ qmp_callback_t callback;
+};
+
+struct qmp_command_list_t qmp_command_list[] = {
+ [QMP_COMMAND_QUERY_CHARDEV] = { "query-chardev",
register_serial0_chardev_callback },
+ [QMP_COMMAND_NUMBER] = { NULL, NULL },
+};
+
+/*
+ * json_object functions
+ */
+
+static int json_object_append_to(libxl__qmp_handler *qmp, json_object *obj,
json_object *dst)
+{
+ if (!dst)
+ return -1;
+
+ switch (dst->type) {
+ case JSON_MAP: {
+ json_map_node *last;
+
+ flexarray_get(dst->u.map, dst->u.map->count - 1, (void**)&last);
+ last->obj = obj;
+ break;
+ }
+ case JSON_ARRAY:
+ flexarray_append(dst->u.array, obj);
+ break;
+ default:
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_ERROR,
+ "error, try append an object to a %i\n", dst->type);
+ return -1;
+ }
+
+ obj->parent = dst;
+ return 0;
+}
+
+static void json_object_free(libxl__qmp_handler *qmp, json_object *obj)
+{
+ int index = 0;
+
+ if (obj == NULL)
+ return;
+ switch (obj->type) {
+ case JSON_ERROR:
+ case JSON_NULL:
+ case JSON_BOOL:
+ case JSON_INTEGER:
+ case JSON_DOUBLE:
+ break;
+ case JSON_STRING:
+ free((void*)obj->u.string);
+ break;
+ case JSON_MAP: {
+ json_map_node *node = NULL;
+
+ for (index = 0; index < obj->u.map->count; index++) {
+ if (flexarray_get(obj->u.map, index, (void**)&node) != 0)
+ break;
+ json_object_free(qmp, node->obj);
+ free((void*)node->map_key);
+ free(node);
+ node = NULL;
+ }
+ flexarray_free(obj->u.map);
+ break;
+ }
+ case JSON_ARRAY:{
+ json_object *node = NULL;
+ break;
+
+ for (index = 0; index < obj->u.array->count; index++) {
+ if (flexarray_get(obj->u.array, index, (void**)&node) != 0)
+ break;
+ json_object_free(qmp, node);
+ node = NULL;
+ }
+ flexarray_free(obj->u.array);
+ break;
+ }
+ }
+ free(obj);
+}
+
+static inline const char *json_object_get_string(const json_object *o)
+{
+ if (o && o->type == JSON_STRING) {
+ return o->u.string;
+ }
+ return NULL;
+}
+
+static const json_object *json_object_map_get(const char *key, const
json_object *o)
+{
+ flexarray_t *maps = NULL;
+ int index = 0;
+
+ if (o && o->type == JSON_MAP) {
+ json_map_node *node = NULL;
+
+ maps = o->u.map;
+ for (index = 0; index < maps->count; index++) {
+ if (flexarray_get(maps, index, (void**)&node) != 0)
+ break;
+ if (strcmp(key, node->map_key) == 0) {
+ return node->obj;
+ }
+ }
+ }
+ return NULL;
+}
+
+/*
+ * JSON callbacks
+ */
+
+static int json_callback_null(void *opaque)
+{
+ libxl__qmp_handler *qmp = opaque;
+ json_object *obj;
+
+#ifdef DEBUG_ANSWER
+ yajl_gen_null(qmp->g);
+#endif
+
+ obj = calloc(1, sizeof (json_object));
+ obj->type = JSON_NULL;
+ json_object_append_to(qmp, obj, qmp->current);
+
+ return 1;
+}
+
+static int json_callback_boolean(void *opaque, int boolean)
+{
+ libxl__qmp_handler *qmp = opaque;
+ json_object *obj;
+
+#ifdef DEBUG_ANSWER
+ yajl_gen_bool(qmp->g, boolean);
+#endif
+
+ obj = calloc(1, sizeof (json_object));
+ obj->type = JSON_BOOL;
+ obj->u.boolean = boolean;
+ json_object_append_to(qmp, obj, qmp->current);
+
+ return 1;
+}
+
+static int json_callback_integer(void *opaque, long value)
+{
+ libxl__qmp_handler *qmp = opaque;
+ json_object *obj;
+
+#ifdef DEBUG_ANSWER
+ yajl_gen_integer(qmp->g, value);
+#endif
+
+ obj = calloc(1, sizeof (json_object));
+ obj->type = JSON_INTEGER;
+ obj->u.integer = value;
+ json_object_append_to(qmp, obj, qmp->current);
+
+ return 1;
+}
+
+static int json_callback_double(void *opaque, double value)
+{
+ libxl__qmp_handler *qmp = opaque;
+ json_object *obj;
+
+#ifdef DEBUG_ANSWER
+ yajl_gen_double(qmp->g, value);
+#endif
+
+ obj = calloc(1, sizeof (json_object));
+ obj->type = JSON_DOUBLE;
+ obj->u.floating = value;
+ json_object_append_to(qmp, obj, qmp->current);
+
+ return 1;
+}
+
+static int json_callback_string(void *opaque, const unsigned char *str,
+ unsigned int len)
+{
+ libxl__qmp_handler *qmp = opaque;
+ char *t = malloc(len + 1);
+ json_object *obj = NULL;
+
+#ifdef DEBUG_ANSWER
+ yajl_gen_string(qmp->g, str, len);
+#endif
+
+ strncpy(t, (const char *) str, len);
+ t[len] = 0;
+
+ obj = calloc(1, sizeof (json_object));
+ obj->type = JSON_STRING;
+ obj->u.string = t;
+
+ json_object_append_to(qmp, obj, qmp->current);
+
+ return 1;
+}
+
+static int json_callback_map_key(void *opaque, const unsigned char *str,
+ unsigned int len)
+{
+ libxl__qmp_handler *qmp = opaque;
+ char *t = malloc(len + 1);
+ json_object *obj = qmp->current;
+
+#ifdef DEBUG_ANSWER
+ yajl_gen_string(qmp->g, str, len);
+#endif
+
+ strncpy(t, (const char *) str, len);
+ t[len] = 0;
+
+ if (obj->type == JSON_MAP) {
+ json_map_node *node = malloc(sizeof (json_map_node));
+
+ node->map_key = t;
+ node->obj = NULL;
+
+ flexarray_append(obj->u.map, node);
+ } else {
+ return 0;
+ }
+
+ return 1;
+}
+
+static int json_callback_start_map(void *opaque)
+{
+ libxl__qmp_handler *qmp = opaque;
+ json_object *obj = NULL;
+
+#ifdef DEBUG_ANSWER
+ yajl_gen_map_open(qmp->g);
+#endif
+
+ obj = calloc(1, sizeof (json_object));
+ if (qmp->head == NULL) {
+ qmp->head = obj;
+ }
+
+ obj->type = JSON_MAP;
+ obj->u.map = flexarray_make(1, 1);
+
+ json_object_append_to(qmp, obj, qmp->current);
+
+ obj->parent = qmp->current;
+ qmp->current = obj;
+
+ return 1;
+}
+
+static int json_callback_end_map(void *opaque)
+{
+ libxl__qmp_handler *qmp = opaque;
+
+#ifdef DEBUG_ANSWER
+ yajl_gen_map_close(qmp->g);
+#endif
+
+ if (qmp->current) {
+ qmp->current = qmp->current->parent;
+ } else {
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_ERROR, "no parents for a json_object");
+ return 0;
+ }
+
+ return 1;
+}
+
+static int json_callback_start_array(void *opaque)
+{
+ libxl__qmp_handler *qmp = opaque;
+ json_object *obj = NULL;
+
+#ifdef DEBUG_ANSWER
+ yajl_gen_array_open(qmp->g);
+#endif
+
+ obj = calloc(1, sizeof (json_object));
+ if (qmp->head == NULL) {
+ qmp->head = obj;
+ }
+ obj->type = JSON_ARRAY;
+ obj->u.array = flexarray_make(1, 1);
+ json_object_append_to(qmp, obj, qmp->current);
+ qmp->current = obj;
+
+ return 1;
+}
+
+static int json_callback_end_array(void *opaque)
+{
+ libxl__qmp_handler *qmp = opaque;
+
+#ifdef DEBUG_ANSWER
+ yajl_gen_array_close(qmp->g);
+#endif
+
+ if (qmp->current) {
+ qmp->current = qmp->current->parent;
+ } else {
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_ERROR, "no parents for a json_object");
+ return 0;
+ }
+
+ return 1;
+}
+
+static yajl_callbacks callbacks = {
+ json_callback_null,
+ json_callback_boolean,
+ json_callback_integer,
+ json_callback_double,
+ NULL,
+ json_callback_string,
+ json_callback_start_map,
+ json_callback_map_key,
+ json_callback_end_map,
+ json_callback_start_array,
+ json_callback_end_array
+};
+
+/*
+ * QMP callbacks functions
+ */
+
+static const char *get_serial0_chardev(libxl__qmp_handler *qmp, const
json_object *tree)
+{
+ const json_object *ret = NULL;
+ const json_object *obj = NULL;
+ const json_object *label = NULL;
+ const char *s = NULL;
+ flexarray_t *array = NULL;
+ int index = 0;
+
+ ret = json_object_map_get("return", tree);
+
+ if (!ret || ret->type != JSON_ARRAY) {
+ return NULL;
+ }
+ array = ret->u.array;
+ for (index = 0; index < array->count; index++) {
+ if (flexarray_get(array, index, (void**)&obj) != 0)
+ break;
+ label = json_object_map_get("label", obj);
+ s = json_object_get_string(label);
+
+ /* TODO Could replace serial0 by serial and get all serial ttys, if
sevral */
+ if (s && strcmp("serial0", s) == 0) {
+ const json_object *filename = NULL;
+ filename = json_object_map_get("filename", obj);
+ return json_object_get_string(filename);
+ }
+ };
+
+ return NULL;
+}
+
+static int register_serial0_chardev_callback(libxl__qmp_handler *qmp, const
json_object *tree)
+{
+ libxl__gc gc = LIBXL_INIT_GC(qmp->ctx);
+ char *path = NULL;
+ const char *chardev = NULL;
+ int ret = 0;
+
+ chardev = get_serial0_chardev(qmp, tree);
+ if (!(chardev && strncmp("pty:", chardev, 4) == 0)) {
+ return 1;
+ }
+
+ path = libxl__xs_get_dompath(&gc, qmp->domid);
+ path = libxl__sprintf(&gc, "%s/serial/%d/tty", path, 0);
+
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_DEBUG,
+ "qmp serial0: %s (%s)", chardev + 4, path);
+ ret = libxl__xs_write(&gc, XBT_NULL, path, "%s", chardev + 4);
+ libxl__free_all(&gc);
+ return ret;
+}
+
+static int qmp_capabilities_callback(libxl__qmp_handler *qmp, const
json_object *tree)
+{
+ int ret = 0;
+
+ qmp->connected = true;
+
+ return ret;
+}
+
+/*
+ * QMP commands
+ */
+
+static int enable_qmp_capabilities(libxl__qmp_handler *qmp)
+{
+ return qmp_send(qmp, "qmp_capabilities", qmp_capabilities_callback);
+}
+
+/*
+ * Helpers
+ */
+
+static message_type_e qmp_response_type(libxl__qmp_handler *qmp, json_object
*resp)
+{
+ if (resp && resp->type == JSON_MAP) {
+ flexarray_t *maps = NULL;
+ json_map_node *node = NULL;
+ int index = 0;
+
+ maps = resp->u.map;
+ for (index = 0; index < maps->count; index++) {
+ int i = 0;
+ if (flexarray_get(maps, index, (void**)&node) != 0)
+ break;
+ for (i = 0; member_name_to_message_type[i].type != QMP_ANY; i++) {
+ if (strcmp(member_name_to_message_type[i].name, node->map_key)
== 0) {
+ return member_name_to_message_type[i].type;
+ }
+ }
+ }
+ }
+
+ return QMP_ANY;
+}
+
+static callback_id_pair *qmp_get_callback_from_id(libxl__qmp_handler *qmp,
json_object *o)
+{
+ const json_object *id_object = json_object_map_get("id", o);
+ int id = -1;
+ callback_id_pair *pp = NULL;
+
+ if (id_object && id_object->type == JSON_INTEGER) {
+ id = id_object->u.integer;
+
+ SIMPLEQ_FOREACH(pp, &qmp->callback_list, next) {
+ if (pp->id == id) {
+ return pp;
+ }
+ }
+ }
+ return NULL;
+}
+
+static void qmp_handle_error_response(libxl__qmp_handler *qmp, json_object
*resp)
+{
+ callback_id_pair *pp = qmp_get_callback_from_id(qmp, resp);
+ const json_object *error = json_object_map_get("error", resp);
+ const char *msg = json_object_get_string(json_object_map_get("desc",
error));
+
+ if (pp) {
+ if (pp->id == qmp->wait_for_id) {
+ /* tell that the id have been processed */
+ qmp->wait_for_id = 0;
+ }
+ SIMPLEQ_REMOVE(&qmp->callback_list, pp, callback_id_pair, next);
+ free(pp);
+ }
+
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_ERROR,
+ "receive an error message from QMP server: %s",
+ msg);
+}
+
+static int qmp_handle_response(libxl__qmp_handler *qmp, json_object *resp)
+{
+ message_type_e type = QMP_ANY;
+
+ type = qmp_response_type(qmp, resp);
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_DEBUG, "message type: %i", type);
+
+ switch (type) {
+ case QMP_QMP:
+ /* On the greeting message from the server, enable qmp capabilities */
+ enable_qmp_capabilities(qmp);
+ break;
+ case QMP_RETURN: {
+ callback_id_pair *pp = qmp_get_callback_from_id(qmp, resp);
+
+ if (pp) {
+ pp->callback(qmp, resp);
+ if (pp->id == qmp->wait_for_id) {
+ /* tell that the id have been processed */
+ qmp->wait_for_id = 0;
+ }
+ SIMPLEQ_REMOVE(&qmp->callback_list, pp, callback_id_pair, next);
+ free(pp);
+ }
+ break;
+ }
+ case QMP_ERROR:
+ qmp_handle_error_response(qmp, resp);
+ break;
+ case QMP_EVENT:
+ break;
+ case QMP_ANY:
+ return -1;
+ }
+ return 0;
+}
+
+/*
+ * Handler functions
+ */
+
+static int qmp_connect(libxl__qmp_handler *qmp, const char *qmp_socket_path,
+ int timeout)
+{
+ int ret;
+ int i = 0;
+
+ qmp->qmp_fd = socket(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, 0);
+ if (qmp->qmp_fd < 0) {
+ return -1;
+ }
+
+ memset(&qmp->addr, 0, sizeof (&qmp->addr));
+ qmp->addr.sun_family = AF_UNIX;
+ strncpy(qmp->addr.sun_path, qmp_socket_path, sizeof (qmp->addr.sun_path));
+
+ do {
+ ret = connect(qmp->qmp_fd, (struct sockaddr *) &qmp->addr,
+ sizeof (qmp->addr));
+ if (ret == 0)
+ break;
+ if (errno == ENOENT || errno == ECONNREFUSED) {
+ /* ENOENT : Socket may not have shown up yet
+ * ECONNREFUSED : Leftover socket hasn't been removed yet */
+ continue;
+ }
+ return -1;
+ } while ((++i <= timeout * 5) && (usleep(.2 * 1000000) <= 0));
+
+ if (ret == -1)
+ return -1;
+
+ return 0;
+}
+
+static void qmp_close(libxl__qmp_handler *qmp)
+{
+ callback_id_pair *pp = NULL;
+ callback_id_pair *tmp = NULL;
+#ifdef DEBUG_ANSWER
+ if (qmp->g)
+ yajl_gen_free(qmp->g);
+#endif
+ if (qmp->hand)
+ yajl_free(qmp->hand);
+ close(qmp->qmp_fd);
+ SIMPLEQ_FOREACH(pp, &qmp->callback_list, next) {
+ if (tmp)
+ free(tmp);
+ tmp = pp;
+ }
+ if (tmp)
+ free(tmp);
+}
+
+static int qmp_next(libxl__qmp_handler *qmp)
+{
+ yajl_status status;
+ ssize_t rd;
+ ssize_t bytes_parsed = 0;
+
+ /* read the socket */
+ rd = read(qmp->qmp_fd, qmp->buffer, QMP_RECEIVE_BUFFER_SIZE);
+ if (rd <= 0) {
+ /* either an error, or nothing */
+ return rd;
+ }
+#ifdef DEBUG_RECEIVE
+ qmp->buffer[rd] = 0;
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_DEBUG, "received: '%s'", qmp->buffer);
+#endif
+
+ while (bytes_parsed < rd) {
+#ifdef DEBUG_ANSWER
+ if (qmp->g == NULL) {
+ yajl_gen_config conf = { 1, " " };
+ qmp->g = yajl_gen_alloc(&conf, NULL);
+ }
+#endif
+ /* parse the input */
+ if (qmp->hand == NULL) {
+ /* allow comments */
+ yajl_parser_config cfg = { 1, 1 };
+ qmp->hand = yajl_alloc(&callbacks, &cfg, NULL, qmp);
+ }
+ status = yajl_parse(qmp->hand, qmp->buffer + bytes_parsed, rd -
bytes_parsed);
+ bytes_parsed += yajl_get_bytes_consumed(qmp->hand);
+
+ /* handle the answer */
+ if (status != yajl_status_ok && status !=
yajl_status_insufficient_data) {
+ unsigned char *str = yajl_get_error(qmp->hand, 1, qmp->buffer, rd);
+
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_ERROR, "yajl error: %s", str);
+ yajl_free_error(qmp->hand, str);
+ }
+
+ if (status == yajl_status_ok) {
+#ifdef DEBUG_ANSWER
+ const unsigned char *buf = NULL;
+ unsigned int len = 0;
+
+ yajl_gen_get_buf(qmp->g, &buf, &len);
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_DEBUG, "response:\n%s", buf);
+ yajl_gen_free(qmp->g);
+ qmp->g = NULL;
+#endif
+
+ qmp_handle_response(qmp, qmp->head);
+
+ json_object_free(qmp, qmp->head);
+ qmp->head = NULL;
+ qmp->current = NULL;
+
+ yajl_free(qmp->hand);
+ qmp->hand = NULL;
+ }
+ /* skip the CRLF of the end of a command */
+ while (bytes_parsed < rd && (qmp->buffer[bytes_parsed] == '\r'
+ || qmp->buffer[bytes_parsed] == '\n')) {
+ bytes_parsed++;
+ }
+ }
+ return 1;
+}
+
+static int qmp_send(libxl__qmp_handler *qmp, const char *cmd, qmp_callback_t
callback)
+{
+ yajl_gen_config conf = { 0, NULL };
+ const unsigned char *buf;
+ const char *ex = "execute";
+ unsigned int len = 0;
+ yajl_gen_status s;
+ yajl_gen hand;
+
+ hand = yajl_gen_alloc(&conf, NULL);
+ if (!hand) {
+ return -1;
+ }
+
+ yajl_gen_map_open(hand);
+ yajl_gen_string(hand, (const unsigned char *)ex, strlen(ex));
+ yajl_gen_string(hand, (const unsigned char *)cmd, strlen(cmd));
+ yajl_gen_string(hand, (const unsigned char *)"id", 2);
+ yajl_gen_integer(hand, ++qmp->last_id_used);
+ yajl_gen_map_close(hand);
+
+ s = yajl_gen_get_buf(hand, &buf, &len);
+
+ if (s) {
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_ERROR,
+ "could not generate a qmp command");
+ return -1;
+ }
+
+ if (callback) {
+ callback_id_pair *elm = malloc(sizeof (callback_id_pair));
+ elm->id = qmp->last_id_used;
+ elm->callback = callback;
+ SIMPLEQ_INSERT_TAIL(&qmp->callback_list, elm, next);
+ }
+
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_DEBUG, "next qmp command: '%s'", buf);
+
+ write(qmp->qmp_fd, buf, len);
+ write(qmp->qmp_fd, "\r\n", 2);
+ yajl_gen_free(hand);
+
+ return qmp->last_id_used;
+}
+
+static int qmp_synchronous_send(libxl__qmp_handler *qmp, const char *cmd,
qmp_callback_t callback, int ask_timeout)
+{
+ int id = 0;
+ int ret = 0;
+ fd_set rfds;
+ struct timeval timeout;
+
+ id = qmp_send(qmp, cmd, callback);
+ if (id <= 0) {
+ return -1;
+ }
+ qmp->wait_for_id = id;
+
+ timeout.tv_sec = ask_timeout;
+ timeout.tv_usec = 0;
+
+ while (qmp->wait_for_id == id) {
+ FD_ZERO(&rfds);
+ FD_SET(qmp->qmp_fd, &rfds);
+ ret = select(qmp->qmp_fd + 1, &rfds, NULL, NULL, &timeout);
+ if (ret > 0) {
+ if ((ret = qmp_next(qmp)) < 0) {
+ return ret;
+ }
+ } else if (ret < 0) {
+ LIBXL__LOG_ERRNO(qmp->ctx, LIBXL__LOG_ERROR, "Select error");
+ return -1;
+ }
+ }
+ return 0;
+}
+
+static libxl__qmp_handler *qmp_init_handler(libxl_ctx *ctx, uint32_t domid)
+{
+ libxl__qmp_handler *qmp = NULL;
+
+ qmp = calloc(1, sizeof (libxl__qmp_handler));
+ qmp->ctx = ctx;
+ qmp->domid = domid;
+ if ((qmp->buffer = malloc(QMP_RECEIVE_BUFFER_SIZE)) == NULL) {
+ LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "Can not allocate the
reception buffer");
+ free(qmp);
+ return NULL;
+ }
+
+ SIMPLEQ_INIT(&qmp->callback_list);
+
+ return qmp;
+}
+
+static void qmp_free_handler(libxl__qmp_handler *qmp)
+{
+ if (qmp->buffer)
+ free(qmp->buffer);
+ free(qmp);
+}
+
+/*
+ * API
+ */
+
+libxl__qmp_handler *libxl__qmp_initialize(libxl_ctx *ctx, uint32_t domid)
+{
+ int ret = 0;
+ libxl__qmp_handler *qmp = NULL;
+ char qmp_socket[40];
+ fd_set rfds;
+ struct timeval timeout;
+
+ qmp = qmp_init_handler(ctx, domid);
+
+ snprintf(qmp_socket, sizeof (qmp_socket), "%s/qmp-%d",
+ libxl_run_dir_path(), domid);
+ if ((ret = qmp_connect(qmp, qmp_socket, QMP_SOCKET_CONNECT_TIMEOUT)) < 0) {
+ LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "Connection error");
+ qmp_free_handler(qmp);
+ return NULL;
+ }
+
+ LIBXL__LOG(qmp->ctx, LIBXL__LOG_DEBUG, "connected to %s", qmp_socket);
+
+ timeout.tv_sec = 5;
+ timeout.tv_usec = 0;
+
+ /* Wait for the response to qmp_capabilities */
+ while (!qmp->connected) {
+ FD_ZERO(&rfds);
+ FD_SET(qmp->qmp_fd, &rfds);
+ ret = select(qmp->qmp_fd + 1, &rfds, NULL, NULL, &timeout);
+ if (ret > 0) {
+ if ((ret = qmp_next(qmp)) < 0) {
+ break;
+ }
+ } else if (ret < 0) {
+ LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "Select error");
+ break;
+ }
+ }
+
+ return qmp;
+}
+
+int libxl__qmp_get_fd(libxl__qmp_handler *qmp)
+{
+ if (qmp)
+ return qmp->qmp_fd;
+ else
+ return -1;
+}
+
+int libxl__qmp_send_command(libxl__qmp_handler *qmp, libxl__qmp_command_e
command)
+{
+ return qmp_synchronous_send(qmp, qmp_command_list[command].cmd,
qmp_command_list[command].callback, 5);
+}
+
+int libxl__qmp_do_next(libxl__qmp_handler *qmp)
+{
+ int ret;
+
+ if (!qmp)
+ return -1;
+ ret = qmp_next(qmp);
+ if (ret < 0) {
+ LIBXL__LOG_ERRNO(qmp->ctx, LIBXL__LOG_ERROR, "QMP, read error");
+ }
+
+ return ret;
+}
+
+void libxl__qmp_close(libxl__qmp_handler *qmp)
+{
+ if (!qmp)
+ return;
+ qmp_close(qmp);
+ qmp_free_handler(qmp);
+}
+
+int libxl__qmp_initializations(libxl_ctx *ctx, uint32_t domid)
+{
+ libxl__qmp_handler *qmp = NULL;
+ int ret = 0;
+
+ qmp = libxl__qmp_initialize(ctx, domid);
+ if (!qmp)
+ return -1;
+ if (qmp->connected) {
+ ret = libxl__qmp_send_command(qmp, QMP_COMMAND_QUERY_CHARDEV);
+ }
+ libxl__qmp_close(qmp);
+ return ret;
+}
diff --git a/tools/libxl/libxl_qmp.h b/tools/libxl/libxl_qmp.h
new file mode 100644
index 0000000..d11b9ba
--- /dev/null
+++ b/tools/libxl/libxl_qmp.h
@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2011 Citrix Ltd.
+ * Author Anthony PERARD <anthony.perard@xxxxxxxxxx>
+ *
+ * This program 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; version 2.1 only. with the special
+ * exception on linking described in file LICENSE.
+ *
+ * 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 Lesser General Public License for more details.
+ */
+
+#include "libxl.h"
+
+typedef struct libxl__qmp_handler libxl__qmp_handler;
+typedef enum libxl__qmp_command_e libxl__qmp_command_e;
+
+/* QMP Command that can be send */
+enum libxl__qmp_command_e {
+ QMP_COMMAND_QUERY_CHARDEV,
+ QMP_COMMAND_NUMBER,
+};
+
+
+_hidden libxl__qmp_handler *libxl__qmp_initialize(libxl_ctx *ctx,
+ uint32_t domid);
+_hidden int libxl__qmp_get_fd(libxl__qmp_handler *qmp);
+_hidden int libxl__qmp_send_command(libxl__qmp_handler *qmp,
libxl__qmp_command_e command);
+_hidden int libxl__qmp_do_next(libxl__qmp_handler *qmp);
+_hidden void libxl__qmp_close(libxl__qmp_handler *qmp);
+
+_hidden int libxl__qmp_initializations(libxl_ctx *ctx, uint32_t domid);
--
1.7.2.5
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