unicorn/qemu/qapi/string-input-visitor.c
Eric Blake eeffd97458
qapi: Make all visitors supply uint64 callbacks
Our qapi visitor contract supports multiple integer visitors,
but left the type_uint64 visitor as optional (falling back on
type_int64); which in turn can lead to awkward behavior with
numbers larger than INT64_MAX (the user has to be aware of
twos complement, and deal with negatives).

This patch does not address the disparity in handling large
values as negatives. It merely moves the fallback from uint64
to int64 from the visitor core to the visitors, where the issue
can actually be fixed, by implementing the missing type_uint64()
callbacks on top of the respective type_int64() callbacks, and
with a FIXME comment explaining why that's wrong.

With that done, we now have a type_uint64() callback in every
driver, so we can make it mandatory from the core. And although
the type_int64() callback can cover the entire valid range of
type_uint{8,16,32} on valid user input, using type_uint64() to
avoid mixed signedness makes more sense.

Backports commit f755dea79dc81b0d6a8f6414e0672e165e28d8ba from qemu
2018-02-19 11:59:22 -05:00

346 lines
8.6 KiB
C

/*
* String parsing visitor
*
* Copyright Red Hat, Inc. 2012
*
* Author: Paolo Bonzini <pbonzini@redhat.com>
*
* This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "qapi/string-input-visitor.h"
#include "qapi/visitor-impl.h"
#include "qapi/qmp/qerror.h"
#include "qemu/queue.h"
#include "qemu/range.h"
#include <stdlib.h> // strtoll
struct StringInputVisitor
{
Visitor visitor;
bool head;
GList *ranges;
GList *cur_range;
int64_t cur;
const char *string;
};
static StringInputVisitor *to_siv(Visitor *v)
{
return container_of(v, StringInputVisitor, visitor);
}
static void free_range(void *range, void *dummy)
{
g_free(range);
}
static void parse_str(StringInputVisitor *siv, Error **errp)
{
char *str = (char *) siv->string;
long long start, end;
Range *cur;
char *endptr;
if (siv->ranges) {
return;
}
do {
errno = 0;
start = strtoll(str, &endptr, 0);
if (errno == 0 && endptr > str) {
if (*endptr == '\0') {
cur = g_malloc0(sizeof(*cur));
cur->begin = start;
cur->end = start + 1;
siv->ranges = g_list_insert_sorted_merged(siv->ranges, cur,
range_compare);
cur = NULL;
str = NULL;
} else if (*endptr == '-') {
str = endptr + 1;
errno = 0;
end = strtoll(str, &endptr, 0);
if (errno == 0 && endptr > str && start <= end &&
(start > INT64_MAX - 65536 ||
end < start + 65536)) {
if (*endptr == '\0') {
cur = g_malloc0(sizeof(*cur));
cur->begin = start;
cur->end = end + 1;
siv->ranges =
g_list_insert_sorted_merged(siv->ranges,
cur,
range_compare);
cur = NULL;
str = NULL;
} else if (*endptr == ',') {
str = endptr + 1;
cur = g_malloc0(sizeof(*cur));
cur->begin = start;
cur->end = end + 1;
siv->ranges =
g_list_insert_sorted_merged(siv->ranges,
cur,
range_compare);
cur = NULL;
} else {
goto error;
}
} else {
goto error;
}
} else if (*endptr == ',') {
str = endptr + 1;
cur = g_malloc0(sizeof(*cur));
cur->begin = start;
cur->end = start + 1;
siv->ranges = g_list_insert_sorted_merged(siv->ranges,
cur,
range_compare);
cur = NULL;
} else {
goto error;
}
} else {
goto error;
}
} while (str);
return;
error:
g_list_foreach(siv->ranges, free_range, NULL);
g_list_free(siv->ranges);
siv->ranges = NULL;
}
static void
start_list(Visitor *v, const char *name, Error **errp)
{
StringInputVisitor *siv = to_siv(v);
parse_str(siv, errp);
siv->cur_range = g_list_first(siv->ranges);
if (siv->cur_range) {
Range *r = siv->cur_range->data;
if (r) {
siv->cur = r->begin;
}
}
}
static GenericList *
next_list(Visitor *v, GenericList **list, Error **errp)
{
StringInputVisitor *siv = to_siv(v);
GenericList **link;
Range *r;
if (!siv->ranges || !siv->cur_range) {
return NULL;
}
r = siv->cur_range->data;
if (!r) {
return NULL;
}
if ((uint64_t)siv->cur < r->begin || (uint64_t)siv->cur >= r->end) {
siv->cur_range = g_list_next(siv->cur_range);
if (!siv->cur_range) {
return NULL;
}
r = siv->cur_range->data;
if (!r) {
return NULL;
}
siv->cur = r->begin;
}
if (siv->head) {
link = list;
siv->head = false;
} else {
link = &(*list)->next;
}
*link = g_malloc0(sizeof **link);
return *link;
}
static void
end_list(Visitor *v, Error **errp)
{
StringInputVisitor *siv = to_siv(v);
siv->head = true;
}
static void parse_type_int64(Visitor *v, int64_t *obj, const char *name,
Error **errp)
{
StringInputVisitor *siv = to_siv(v);
if (!siv->string) {
error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
"integer");
return;
}
parse_str(siv, errp);
if (!siv->ranges) {
goto error;
}
if (!siv->cur_range) {
Range *r;
siv->cur_range = g_list_first(siv->ranges);
if (!siv->cur_range) {
goto error;
}
r = siv->cur_range->data;
if (!r) {
goto error;
}
siv->cur = r->begin;
}
*obj = siv->cur;
siv->cur++;
return;
error:
error_setg(errp, QERR_INVALID_PARAMETER_VALUE, name,
"an int64 value or range");
}
static void parse_type_uint64(Visitor *v, uint64_t *obj, const char *name,
Error **errp)
{
/* FIXME: parse_type_int64 mishandles values over INT64_MAX */
int64_t i;
Error *err = NULL;
parse_type_int64(v, &i, name, &err);
if (err) {
error_propagate(errp, err);
} else {
*obj = i;
}
}
static void parse_type_bool(Visitor *v, bool *obj, const char *name,
Error **errp)
{
StringInputVisitor *siv = to_siv(v);
if (siv->string) {
if (!strcasecmp(siv->string, "on") ||
!strcasecmp(siv->string, "yes") ||
!strcasecmp(siv->string, "true")) {
*obj = true;
return;
}
if (!strcasecmp(siv->string, "off") ||
!strcasecmp(siv->string, "no") ||
!strcasecmp(siv->string, "false")) {
*obj = false;
return;
}
}
error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
"boolean");
}
static void parse_type_str(Visitor *v, char **obj, const char *name,
Error **errp)
{
StringInputVisitor *siv = to_siv(v);
if (siv->string) {
*obj = g_strdup(siv->string);
} else {
error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
"string");
}
}
static void parse_type_number(Visitor *v, double *obj, const char *name,
Error **errp)
{
StringInputVisitor *siv = to_siv(v);
char *endp = (char *) siv->string;
double val;
errno = 0;
if (siv->string) {
val = strtod(siv->string, &endp);
}
if (!siv->string || errno || endp == siv->string || *endp) {
error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
"number");
return;
}
*obj = val;
}
static void parse_optional(Visitor *v, bool *present, const char *name,
Error **errp)
{
StringInputVisitor *siv = to_siv(v);
if (!siv->string) {
*present = false;
return;
}
*present = true;
}
Visitor *string_input_get_visitor(StringInputVisitor *v)
{
return &v->visitor;
}
void string_input_visitor_cleanup(StringInputVisitor *v)
{
g_list_foreach(v->ranges, free_range, NULL);
g_list_free(v->ranges);
g_free(v);
}
StringInputVisitor *string_input_visitor_new(const char *str)
{
StringInputVisitor *v;
v = g_malloc0(sizeof(*v));
v->visitor.type_enum = input_type_enum;
v->visitor.type_int64 = parse_type_int64;
v->visitor.type_uint64 = parse_type_uint64;
v->visitor.type_size = NULL;
v->visitor.type_bool = parse_type_bool;
v->visitor.type_str = parse_type_str;
v->visitor.type_number = parse_type_number;
v->visitor.start_list = start_list;
v->visitor.next_list = next_list;
v->visitor.end_list = end_list;
v->visitor.optional = parse_optional;
v->string = str;
v->head = true;
return v;
}