qemu/error.c
Paolo Bonzini d195325b05 qapi: fix error propagation
Don't overwrite / leak previously set errors.
Make traversal cope with missing mandatory sub-structs.
Don't try to end a container that could not be started.

v1->v2:
- unchanged

v2->v3:
- instead of examining, assert that we never overwrite errors with
  error_set()
- allow visitors to set a NULL struct pointer successfully, so traversal
  of incomplete objects can continue
- check for a NULL "obj" before accessing "(*obj)->has_XXX" (this is not a
  typo, "obj != NULL" implies "*obj != NULL" here)
- fix start_struct / end_struct balance for unions as well

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-07-23 11:55:17 +01:00

161 lines
3.0 KiB
C

/*
* QEMU Error Objects
*
* Copyright IBM, Corp. 2011
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU LGPL, version 2. See
* the COPYING.LIB file in the top-level directory.
*/
#include "qemu-common.h"
#include "error.h"
#include "qjson.h"
#include "qdict.h"
#include "error_int.h"
#include "qerror.h"
struct Error
{
QDict *obj;
const char *fmt;
char *msg;
};
void error_set(Error **errp, const char *fmt, ...)
{
Error *err;
va_list ap;
if (errp == NULL) {
return;
}
assert(*errp == NULL);
err = g_malloc0(sizeof(*err));
va_start(ap, fmt);
err->obj = qobject_to_qdict(qobject_from_jsonv(fmt, &ap));
va_end(ap);
err->fmt = fmt;
*errp = err;
}
Error *error_copy(const Error *err)
{
Error *err_new;
err_new = g_malloc0(sizeof(*err));
err_new->msg = g_strdup(err->msg);
err_new->fmt = err->fmt;
err_new->obj = err->obj;
QINCREF(err_new->obj);
return err_new;
}
bool error_is_set(Error **errp)
{
return (errp && *errp);
}
const char *error_get_pretty(Error *err)
{
if (err->msg == NULL) {
QString *str;
str = qerror_format(err->fmt, err->obj);
err->msg = g_strdup(qstring_get_str(str));
QDECREF(str);
}
return err->msg;
}
const char *error_get_field(Error *err, const char *field)
{
if (strcmp(field, "class") == 0) {
return qdict_get_str(err->obj, field);
} else {
QDict *dict = qdict_get_qdict(err->obj, "data");
return qdict_get_str(dict, field);
}
}
QDict *error_get_data(Error *err)
{
QDict *data = qdict_get_qdict(err->obj, "data");
QINCREF(data);
return data;
}
void error_set_field(Error *err, const char *field, const char *value)
{
QDict *dict = qdict_get_qdict(err->obj, "data");
qdict_put(dict, field, qstring_from_str(value));
}
void error_free(Error *err)
{
if (err) {
QDECREF(err->obj);
g_free(err->msg);
g_free(err);
}
}
bool error_is_type(Error *err, const char *fmt)
{
const char *error_class;
char *ptr;
char *end;
if (!err) {
return false;
}
ptr = strstr(fmt, "'class': '");
assert(ptr != NULL);
ptr += strlen("'class': '");
end = strchr(ptr, '\'');
assert(end != NULL);
error_class = error_get_field(err, "class");
if (strlen(error_class) != end - ptr) {
return false;
}
return strncmp(ptr, error_class, end - ptr) == 0;
}
void error_propagate(Error **dst_err, Error *local_err)
{
if (dst_err && !*dst_err) {
*dst_err = local_err;
} else if (local_err) {
error_free(local_err);
}
}
QObject *error_get_qobject(Error *err)
{
QINCREF(err->obj);
return QOBJECT(err->obj);
}
void error_set_qobject(Error **errp, QObject *obj)
{
Error *err;
if (errp == NULL) {
return;
}
err = g_malloc0(sizeof(*err));
err->obj = qobject_to_qdict(obj);
qobject_incref(obj);
*errp = err;
}