2012-02-09 09:36:37 +01:00
|
|
|
/*
|
|
|
|
* String printing Visitor
|
|
|
|
*
|
2016-01-29 14:48:59 +01:00
|
|
|
* Copyright Red Hat, Inc. 2012-2016
|
2012-02-09 09:36:37 +01:00
|
|
|
*
|
|
|
|
* 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.
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
|
2016-01-29 18:49:57 +01:00
|
|
|
#include "qemu/osdep.h"
|
2012-02-09 09:36:37 +01:00
|
|
|
#include "qemu-common.h"
|
2012-12-17 18:19:43 +01:00
|
|
|
#include "qapi/string-output-visitor.h"
|
|
|
|
#include "qapi/visitor-impl.h"
|
2014-02-08 11:01:50 +01:00
|
|
|
#include "qemu/host-utils.h"
|
2014-02-08 11:01:57 +01:00
|
|
|
#include <math.h>
|
2014-06-10 13:15:28 +02:00
|
|
|
#include "qemu/range.h"
|
|
|
|
|
|
|
|
enum ListMode {
|
|
|
|
LM_NONE, /* not traversing a list of repeated options */
|
qapi: Simplify semantics of visit_next_list()
The semantics of the list visit are somewhat baroque, with the
following pseudocode when FooList is used:
start()
for (prev = head; cur = next(prev); prev = &cur) {
visit(&cur->value)
}
Note that these semantics (advance before visit) requires that
the first call to next() return the list head, while all other
calls return the next element of the list; that is, every visitor
implementation is required to track extra state to decide whether
to return the input as-is, or to advance. It also requires an
argument of 'GenericList **' to next(), solely because the first
iteration might need to modify the caller's GenericList head, so
that all other calls have to do a layer of dereferencing.
Thankfully, we only have two uses of list visits in the entire
code base: one in spapr_drc (which completely avoids
visit_next_list(), feeding in integers from a different source
than uint8List), and one in qapi-visit.py. That is, all other
list visitors are generated in qapi-visit.c, and share the same
paradigm based on a qapi FooList type, so we can refactor how
lists are laid out with minimal churn among clients.
We can greatly simplify things by hoisting the special case
into the start() routine, and flipping the order in the loop
to visit before advance:
start(head)
for (tail = *head; tail; tail = next(tail)) {
visit(&tail->value)
}
With the simpler semantics, visitors have less state to track,
the argument to next() is reduced to 'GenericList *', and it
also becomes obvious whether an input visitor is allocating a
FooList during visit_start_list() (rather than the old way of
not knowing if an allocation happened until the first
visit_next_list()). As a minor drawback, we now allocate in
two functions instead of one, and have to pass the size to
both functions (unless we were to tweak the input visitors to
cache the size to start_list for reuse during next_list, but
that defeats the goal of less visitor state).
The signature of visit_start_list() is chosen to match
visit_start_struct(), with the new parameters after 'name'.
The spapr_drc case is a virtual visit, done by passing NULL for
list, similarly to how NULL is passed to visit_start_struct()
when a qapi type is not used in those visits. It was easy to
provide these semantics for qmp-output and dealloc visitors,
and a bit harder for qmp-input (several prerequisite patches
refactored things to make this patch straightforward). But it
turned out that the string and opts visitors munge enough other
state during visit_next_list() to make it easier to just
document and require a GenericList visit for now; an assertion
will remind us to adjust things if we need the semantics in the
future.
Several pre-requisite cleanup patches made the reshuffling of
the various visitors easier; particularly the qmp input visitor.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-24-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-04-28 23:45:31 +02:00
|
|
|
LM_STARTED, /* next_list() ready to be called */
|
2014-06-10 13:15:28 +02:00
|
|
|
|
|
|
|
LM_IN_PROGRESS, /* next_list() has been called.
|
|
|
|
*
|
|
|
|
* Generating the next list link will consume the most
|
|
|
|
* recently parsed QemuOpt instance of the repeated
|
|
|
|
* option.
|
|
|
|
*
|
|
|
|
* Parsing a value into the list link will examine the
|
|
|
|
* next QemuOpt instance of the repeated option, and
|
|
|
|
* possibly enter LM_SIGNED_INTERVAL or
|
|
|
|
* LM_UNSIGNED_INTERVAL.
|
|
|
|
*/
|
|
|
|
|
|
|
|
LM_SIGNED_INTERVAL, /* next_list() has been called.
|
|
|
|
*
|
|
|
|
* Generating the next list link will consume the most
|
|
|
|
* recently stored element from the signed interval,
|
|
|
|
* parsed from the most recent QemuOpt instance of the
|
|
|
|
* repeated option. This may consume QemuOpt itself
|
|
|
|
* and return to LM_IN_PROGRESS.
|
|
|
|
*
|
|
|
|
* Parsing a value into the list link will store the
|
|
|
|
* next element of the signed interval.
|
|
|
|
*/
|
|
|
|
|
|
|
|
LM_UNSIGNED_INTERVAL,/* Same as above, only for an unsigned interval. */
|
|
|
|
|
qapi: Simplify semantics of visit_next_list()
The semantics of the list visit are somewhat baroque, with the
following pseudocode when FooList is used:
start()
for (prev = head; cur = next(prev); prev = &cur) {
visit(&cur->value)
}
Note that these semantics (advance before visit) requires that
the first call to next() return the list head, while all other
calls return the next element of the list; that is, every visitor
implementation is required to track extra state to decide whether
to return the input as-is, or to advance. It also requires an
argument of 'GenericList **' to next(), solely because the first
iteration might need to modify the caller's GenericList head, so
that all other calls have to do a layer of dereferencing.
Thankfully, we only have two uses of list visits in the entire
code base: one in spapr_drc (which completely avoids
visit_next_list(), feeding in integers from a different source
than uint8List), and one in qapi-visit.py. That is, all other
list visitors are generated in qapi-visit.c, and share the same
paradigm based on a qapi FooList type, so we can refactor how
lists are laid out with minimal churn among clients.
We can greatly simplify things by hoisting the special case
into the start() routine, and flipping the order in the loop
to visit before advance:
start(head)
for (tail = *head; tail; tail = next(tail)) {
visit(&tail->value)
}
With the simpler semantics, visitors have less state to track,
the argument to next() is reduced to 'GenericList *', and it
also becomes obvious whether an input visitor is allocating a
FooList during visit_start_list() (rather than the old way of
not knowing if an allocation happened until the first
visit_next_list()). As a minor drawback, we now allocate in
two functions instead of one, and have to pass the size to
both functions (unless we were to tweak the input visitors to
cache the size to start_list for reuse during next_list, but
that defeats the goal of less visitor state).
The signature of visit_start_list() is chosen to match
visit_start_struct(), with the new parameters after 'name'.
The spapr_drc case is a virtual visit, done by passing NULL for
list, similarly to how NULL is passed to visit_start_struct()
when a qapi type is not used in those visits. It was easy to
provide these semantics for qmp-output and dealloc visitors,
and a bit harder for qmp-input (several prerequisite patches
refactored things to make this patch straightforward). But it
turned out that the string and opts visitors munge enough other
state during visit_next_list() to make it easier to just
document and require a GenericList visit for now; an assertion
will remind us to adjust things if we need the semantics in the
future.
Several pre-requisite cleanup patches made the reshuffling of
the various visitors easier; particularly the qmp input visitor.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-24-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-04-28 23:45:31 +02:00
|
|
|
LM_END, /* next_list() called, about to see last element. */
|
2014-06-10 13:15:28 +02:00
|
|
|
};
|
|
|
|
|
|
|
|
typedef enum ListMode ListMode;
|
2012-02-09 09:36:37 +01:00
|
|
|
|
|
|
|
struct StringOutputVisitor
|
|
|
|
{
|
|
|
|
Visitor visitor;
|
2014-02-08 11:01:50 +01:00
|
|
|
bool human;
|
2014-06-10 13:15:28 +02:00
|
|
|
GString *string;
|
|
|
|
ListMode list_mode;
|
|
|
|
union {
|
|
|
|
int64_t s;
|
|
|
|
uint64_t u;
|
|
|
|
} range_start, range_end;
|
|
|
|
GList *ranges;
|
2012-02-09 09:36:37 +01:00
|
|
|
};
|
|
|
|
|
2016-01-29 14:48:38 +01:00
|
|
|
static StringOutputVisitor *to_sov(Visitor *v)
|
|
|
|
{
|
|
|
|
return container_of(v, StringOutputVisitor, visitor);
|
|
|
|
}
|
|
|
|
|
2012-02-09 09:36:37 +01:00
|
|
|
static void string_output_set(StringOutputVisitor *sov, char *string)
|
|
|
|
{
|
2014-06-10 13:15:28 +02:00
|
|
|
if (sov->string) {
|
|
|
|
g_string_free(sov->string, true);
|
|
|
|
}
|
|
|
|
sov->string = g_string_new(string);
|
|
|
|
g_free(string);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void string_output_append(StringOutputVisitor *sov, int64_t a)
|
|
|
|
{
|
|
|
|
Range *r = g_malloc0(sizeof(*r));
|
|
|
|
r->begin = a;
|
|
|
|
r->end = a + 1;
|
|
|
|
sov->ranges = g_list_insert_sorted_merged(sov->ranges, r, range_compare);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void string_output_append_range(StringOutputVisitor *sov,
|
|
|
|
int64_t s, int64_t e)
|
|
|
|
{
|
|
|
|
Range *r = g_malloc0(sizeof(*r));
|
|
|
|
r->begin = s;
|
|
|
|
r->end = e + 1;
|
|
|
|
sov->ranges = g_list_insert_sorted_merged(sov->ranges, r, range_compare);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void format_string(StringOutputVisitor *sov, Range *r, bool next,
|
|
|
|
bool human)
|
|
|
|
{
|
|
|
|
if (r->end - r->begin > 1) {
|
|
|
|
if (human) {
|
2014-06-20 07:55:42 +02:00
|
|
|
g_string_append_printf(sov->string, "0x%" PRIx64 "-0x%" PRIx64,
|
2014-06-10 13:15:28 +02:00
|
|
|
r->begin, r->end - 1);
|
|
|
|
|
|
|
|
} else {
|
|
|
|
g_string_append_printf(sov->string, "%" PRId64 "-%" PRId64,
|
|
|
|
r->begin, r->end - 1);
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
if (human) {
|
2014-06-18 16:59:51 +02:00
|
|
|
g_string_append_printf(sov->string, "0x%" PRIx64, r->begin);
|
2014-06-10 13:15:28 +02:00
|
|
|
} else {
|
|
|
|
g_string_append_printf(sov->string, "%" PRId64, r->begin);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
if (next) {
|
|
|
|
g_string_append(sov->string, ",");
|
|
|
|
}
|
2012-02-09 09:36:37 +01:00
|
|
|
}
|
|
|
|
|
2016-01-29 14:48:56 +01:00
|
|
|
static void print_type_int64(Visitor *v, const char *name, int64_t *obj,
|
qapi: Prefer type_int64 over type_int in visitors
The qapi builtin type 'int' is basically shorthand for the type
'int64'. In fact, since no visitor was providing the optional
type_int64() callback, visit_type_int64() was just always falling
back to type_int(), cementing the equivalence between the types.
However, some visitors are providing a type_uint64() callback.
For purposes of code consistency, it is nicer if all visitors
use the paired type_int64/type_uint64 names rather than the
mismatched type_int/type_uint64. So this patch just renames
the signed int callbacks in place, dropping the type_int()
callback as redundant, and a later patch will focus on the
unsigned int callbacks.
Add some FIXMEs to questionable reuse of errp in code touched
by the rename, while at it (the reuse works as long as the
callbacks don't modify value when setting an error, but it's not
a good example to set) - a later patch will then fix those.
No change in functionality here, although further cleanups are
in the pipeline.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-14-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-01-29 14:48:49 +01:00
|
|
|
Error **errp)
|
2012-02-09 09:36:37 +01:00
|
|
|
{
|
2016-01-29 14:48:38 +01:00
|
|
|
StringOutputVisitor *sov = to_sov(v);
|
2014-06-10 13:15:28 +02:00
|
|
|
GList *l;
|
|
|
|
|
|
|
|
switch (sov->list_mode) {
|
|
|
|
case LM_NONE:
|
|
|
|
string_output_append(sov, *obj);
|
|
|
|
break;
|
|
|
|
|
|
|
|
case LM_STARTED:
|
|
|
|
sov->range_start.s = *obj;
|
|
|
|
sov->range_end.s = *obj;
|
|
|
|
sov->list_mode = LM_IN_PROGRESS;
|
|
|
|
return;
|
|
|
|
|
|
|
|
case LM_IN_PROGRESS:
|
|
|
|
if (sov->range_end.s + 1 == *obj) {
|
|
|
|
sov->range_end.s++;
|
|
|
|
} else {
|
|
|
|
if (sov->range_start.s == sov->range_end.s) {
|
|
|
|
string_output_append(sov, sov->range_end.s);
|
|
|
|
} else {
|
|
|
|
assert(sov->range_start.s < sov->range_end.s);
|
|
|
|
string_output_append_range(sov, sov->range_start.s,
|
|
|
|
sov->range_end.s);
|
|
|
|
}
|
|
|
|
|
|
|
|
sov->range_start.s = *obj;
|
|
|
|
sov->range_end.s = *obj;
|
|
|
|
}
|
|
|
|
return;
|
|
|
|
|
|
|
|
case LM_END:
|
|
|
|
if (sov->range_end.s + 1 == *obj) {
|
|
|
|
sov->range_end.s++;
|
|
|
|
assert(sov->range_start.s < sov->range_end.s);
|
|
|
|
string_output_append_range(sov, sov->range_start.s,
|
|
|
|
sov->range_end.s);
|
|
|
|
} else {
|
|
|
|
if (sov->range_start.s == sov->range_end.s) {
|
|
|
|
string_output_append(sov, sov->range_end.s);
|
|
|
|
} else {
|
|
|
|
assert(sov->range_start.s < sov->range_end.s);
|
|
|
|
|
|
|
|
string_output_append_range(sov, sov->range_start.s,
|
|
|
|
sov->range_end.s);
|
|
|
|
}
|
|
|
|
string_output_append(sov, *obj);
|
|
|
|
}
|
|
|
|
break;
|
|
|
|
|
|
|
|
default:
|
|
|
|
abort();
|
|
|
|
}
|
|
|
|
|
|
|
|
l = sov->ranges;
|
|
|
|
while (l) {
|
|
|
|
Range *r = l->data;
|
|
|
|
format_string(sov, r, l->next != NULL, false);
|
|
|
|
l = l->next;
|
|
|
|
}
|
2014-02-08 11:01:50 +01:00
|
|
|
|
|
|
|
if (sov->human) {
|
2014-06-10 13:15:28 +02:00
|
|
|
l = sov->ranges;
|
|
|
|
g_string_append(sov->string, " (");
|
|
|
|
while (l) {
|
|
|
|
Range *r = l->data;
|
2014-06-18 16:59:51 +02:00
|
|
|
format_string(sov, r, l->next != NULL, true);
|
2014-06-10 13:15:28 +02:00
|
|
|
l = l->next;
|
|
|
|
}
|
|
|
|
g_string_append(sov->string, ")");
|
2014-02-08 11:01:50 +01:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2016-01-29 14:48:56 +01:00
|
|
|
static void print_type_uint64(Visitor *v, const char *name, uint64_t *obj,
|
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.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-15-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-01-29 14:48:50 +01:00
|
|
|
Error **errp)
|
|
|
|
{
|
|
|
|
/* FIXME: print_type_int64 mishandles values over INT64_MAX */
|
|
|
|
int64_t i = *obj;
|
2016-01-29 14:48:56 +01:00
|
|
|
print_type_int64(v, name, &i, errp);
|
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.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-15-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-01-29 14:48:50 +01:00
|
|
|
}
|
|
|
|
|
2016-01-29 14:48:56 +01:00
|
|
|
static void print_type_size(Visitor *v, const char *name, uint64_t *obj,
|
|
|
|
Error **errp)
|
2014-02-08 11:01:50 +01:00
|
|
|
{
|
2016-01-29 14:48:38 +01:00
|
|
|
StringOutputVisitor *sov = to_sov(v);
|
2014-02-08 11:01:57 +01:00
|
|
|
static const char suffixes[] = { 'B', 'K', 'M', 'G', 'T', 'P', 'E' };
|
2014-02-08 11:01:50 +01:00
|
|
|
uint64_t div, val;
|
|
|
|
char *out;
|
|
|
|
int i;
|
|
|
|
|
|
|
|
if (!sov->human) {
|
2014-02-08 11:01:57 +01:00
|
|
|
out = g_strdup_printf("%"PRIu64, *obj);
|
2014-02-08 11:01:50 +01:00
|
|
|
string_output_set(sov, out);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
val = *obj;
|
|
|
|
|
2014-02-08 11:01:57 +01:00
|
|
|
/* The exponent (returned in i) minus one gives us
|
|
|
|
* floor(log2(val * 1024 / 1000). The correction makes us
|
|
|
|
* switch to the higher power when the integer part is >= 1000.
|
|
|
|
*/
|
|
|
|
frexp(val / (1000.0 / 1024.0), &i);
|
|
|
|
i = (i - 1) / 10;
|
|
|
|
assert(i < ARRAY_SIZE(suffixes));
|
2014-02-08 11:01:50 +01:00
|
|
|
div = 1ULL << (i * 10);
|
|
|
|
|
2014-02-08 11:01:57 +01:00
|
|
|
out = g_strdup_printf("%"PRIu64" (%0.3g %c%s)", val,
|
|
|
|
(double)val/div, suffixes[i], i ? "iB" : "");
|
2014-02-08 11:01:50 +01:00
|
|
|
string_output_set(sov, out);
|
2012-02-09 09:36:37 +01:00
|
|
|
}
|
|
|
|
|
2016-01-29 14:48:56 +01:00
|
|
|
static void print_type_bool(Visitor *v, const char *name, bool *obj,
|
2012-02-09 09:36:37 +01:00
|
|
|
Error **errp)
|
|
|
|
{
|
2016-01-29 14:48:38 +01:00
|
|
|
StringOutputVisitor *sov = to_sov(v);
|
2012-02-09 09:36:37 +01:00
|
|
|
string_output_set(sov, g_strdup(*obj ? "true" : "false"));
|
|
|
|
}
|
|
|
|
|
2016-01-29 14:48:56 +01:00
|
|
|
static void print_type_str(Visitor *v, const char *name, char **obj,
|
2012-02-09 09:36:37 +01:00
|
|
|
Error **errp)
|
|
|
|
{
|
2016-01-29 14:48:38 +01:00
|
|
|
StringOutputVisitor *sov = to_sov(v);
|
2014-02-08 11:01:50 +01:00
|
|
|
char *out;
|
|
|
|
|
|
|
|
if (sov->human) {
|
|
|
|
out = *obj ? g_strdup_printf("\"%s\"", *obj) : g_strdup("<null>");
|
|
|
|
} else {
|
|
|
|
out = g_strdup(*obj ? *obj : "");
|
|
|
|
}
|
|
|
|
string_output_set(sov, out);
|
2012-02-09 09:36:37 +01:00
|
|
|
}
|
|
|
|
|
2016-01-29 14:48:56 +01:00
|
|
|
static void print_type_number(Visitor *v, const char *name, double *obj,
|
2012-02-09 09:36:37 +01:00
|
|
|
Error **errp)
|
|
|
|
{
|
2016-01-29 14:48:38 +01:00
|
|
|
StringOutputVisitor *sov = to_sov(v);
|
2012-04-30 16:33:30 +02:00
|
|
|
string_output_set(sov, g_strdup_printf("%f", *obj));
|
2012-02-09 09:36:37 +01:00
|
|
|
}
|
|
|
|
|
2014-06-10 13:15:28 +02:00
|
|
|
static void
|
qapi: Simplify semantics of visit_next_list()
The semantics of the list visit are somewhat baroque, with the
following pseudocode when FooList is used:
start()
for (prev = head; cur = next(prev); prev = &cur) {
visit(&cur->value)
}
Note that these semantics (advance before visit) requires that
the first call to next() return the list head, while all other
calls return the next element of the list; that is, every visitor
implementation is required to track extra state to decide whether
to return the input as-is, or to advance. It also requires an
argument of 'GenericList **' to next(), solely because the first
iteration might need to modify the caller's GenericList head, so
that all other calls have to do a layer of dereferencing.
Thankfully, we only have two uses of list visits in the entire
code base: one in spapr_drc (which completely avoids
visit_next_list(), feeding in integers from a different source
than uint8List), and one in qapi-visit.py. That is, all other
list visitors are generated in qapi-visit.c, and share the same
paradigm based on a qapi FooList type, so we can refactor how
lists are laid out with minimal churn among clients.
We can greatly simplify things by hoisting the special case
into the start() routine, and flipping the order in the loop
to visit before advance:
start(head)
for (tail = *head; tail; tail = next(tail)) {
visit(&tail->value)
}
With the simpler semantics, visitors have less state to track,
the argument to next() is reduced to 'GenericList *', and it
also becomes obvious whether an input visitor is allocating a
FooList during visit_start_list() (rather than the old way of
not knowing if an allocation happened until the first
visit_next_list()). As a minor drawback, we now allocate in
two functions instead of one, and have to pass the size to
both functions (unless we were to tweak the input visitors to
cache the size to start_list for reuse during next_list, but
that defeats the goal of less visitor state).
The signature of visit_start_list() is chosen to match
visit_start_struct(), with the new parameters after 'name'.
The spapr_drc case is a virtual visit, done by passing NULL for
list, similarly to how NULL is passed to visit_start_struct()
when a qapi type is not used in those visits. It was easy to
provide these semantics for qmp-output and dealloc visitors,
and a bit harder for qmp-input (several prerequisite patches
refactored things to make this patch straightforward). But it
turned out that the string and opts visitors munge enough other
state during visit_next_list() to make it easier to just
document and require a GenericList visit for now; an assertion
will remind us to adjust things if we need the semantics in the
future.
Several pre-requisite cleanup patches made the reshuffling of
the various visitors easier; particularly the qmp input visitor.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-24-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-04-28 23:45:31 +02:00
|
|
|
start_list(Visitor *v, const char *name, GenericList **list, size_t size,
|
|
|
|
Error **errp)
|
2014-06-10 13:15:28 +02:00
|
|
|
{
|
2016-01-29 14:48:38 +01:00
|
|
|
StringOutputVisitor *sov = to_sov(v);
|
2014-06-10 13:15:28 +02:00
|
|
|
|
|
|
|
/* we can't traverse a list in a list */
|
|
|
|
assert(sov->list_mode == LM_NONE);
|
qapi: Simplify semantics of visit_next_list()
The semantics of the list visit are somewhat baroque, with the
following pseudocode when FooList is used:
start()
for (prev = head; cur = next(prev); prev = &cur) {
visit(&cur->value)
}
Note that these semantics (advance before visit) requires that
the first call to next() return the list head, while all other
calls return the next element of the list; that is, every visitor
implementation is required to track extra state to decide whether
to return the input as-is, or to advance. It also requires an
argument of 'GenericList **' to next(), solely because the first
iteration might need to modify the caller's GenericList head, so
that all other calls have to do a layer of dereferencing.
Thankfully, we only have two uses of list visits in the entire
code base: one in spapr_drc (which completely avoids
visit_next_list(), feeding in integers from a different source
than uint8List), and one in qapi-visit.py. That is, all other
list visitors are generated in qapi-visit.c, and share the same
paradigm based on a qapi FooList type, so we can refactor how
lists are laid out with minimal churn among clients.
We can greatly simplify things by hoisting the special case
into the start() routine, and flipping the order in the loop
to visit before advance:
start(head)
for (tail = *head; tail; tail = next(tail)) {
visit(&tail->value)
}
With the simpler semantics, visitors have less state to track,
the argument to next() is reduced to 'GenericList *', and it
also becomes obvious whether an input visitor is allocating a
FooList during visit_start_list() (rather than the old way of
not knowing if an allocation happened until the first
visit_next_list()). As a minor drawback, we now allocate in
two functions instead of one, and have to pass the size to
both functions (unless we were to tweak the input visitors to
cache the size to start_list for reuse during next_list, but
that defeats the goal of less visitor state).
The signature of visit_start_list() is chosen to match
visit_start_struct(), with the new parameters after 'name'.
The spapr_drc case is a virtual visit, done by passing NULL for
list, similarly to how NULL is passed to visit_start_struct()
when a qapi type is not used in those visits. It was easy to
provide these semantics for qmp-output and dealloc visitors,
and a bit harder for qmp-input (several prerequisite patches
refactored things to make this patch straightforward). But it
turned out that the string and opts visitors munge enough other
state during visit_next_list() to make it easier to just
document and require a GenericList visit for now; an assertion
will remind us to adjust things if we need the semantics in the
future.
Several pre-requisite cleanup patches made the reshuffling of
the various visitors easier; particularly the qmp input visitor.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-24-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-04-28 23:45:31 +02:00
|
|
|
/* We don't support visits without a list */
|
|
|
|
assert(list);
|
|
|
|
/* List handling is only needed if there are at least two elements */
|
|
|
|
if (*list && (*list)->next) {
|
|
|
|
sov->list_mode = LM_STARTED;
|
|
|
|
}
|
2014-06-10 13:15:28 +02:00
|
|
|
}
|
|
|
|
|
qapi: Simplify semantics of visit_next_list()
The semantics of the list visit are somewhat baroque, with the
following pseudocode when FooList is used:
start()
for (prev = head; cur = next(prev); prev = &cur) {
visit(&cur->value)
}
Note that these semantics (advance before visit) requires that
the first call to next() return the list head, while all other
calls return the next element of the list; that is, every visitor
implementation is required to track extra state to decide whether
to return the input as-is, or to advance. It also requires an
argument of 'GenericList **' to next(), solely because the first
iteration might need to modify the caller's GenericList head, so
that all other calls have to do a layer of dereferencing.
Thankfully, we only have two uses of list visits in the entire
code base: one in spapr_drc (which completely avoids
visit_next_list(), feeding in integers from a different source
than uint8List), and one in qapi-visit.py. That is, all other
list visitors are generated in qapi-visit.c, and share the same
paradigm based on a qapi FooList type, so we can refactor how
lists are laid out with minimal churn among clients.
We can greatly simplify things by hoisting the special case
into the start() routine, and flipping the order in the loop
to visit before advance:
start(head)
for (tail = *head; tail; tail = next(tail)) {
visit(&tail->value)
}
With the simpler semantics, visitors have less state to track,
the argument to next() is reduced to 'GenericList *', and it
also becomes obvious whether an input visitor is allocating a
FooList during visit_start_list() (rather than the old way of
not knowing if an allocation happened until the first
visit_next_list()). As a minor drawback, we now allocate in
two functions instead of one, and have to pass the size to
both functions (unless we were to tweak the input visitors to
cache the size to start_list for reuse during next_list, but
that defeats the goal of less visitor state).
The signature of visit_start_list() is chosen to match
visit_start_struct(), with the new parameters after 'name'.
The spapr_drc case is a virtual visit, done by passing NULL for
list, similarly to how NULL is passed to visit_start_struct()
when a qapi type is not used in those visits. It was easy to
provide these semantics for qmp-output and dealloc visitors,
and a bit harder for qmp-input (several prerequisite patches
refactored things to make this patch straightforward). But it
turned out that the string and opts visitors munge enough other
state during visit_next_list() to make it easier to just
document and require a GenericList visit for now; an assertion
will remind us to adjust things if we need the semantics in the
future.
Several pre-requisite cleanup patches made the reshuffling of
the various visitors easier; particularly the qmp input visitor.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-24-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-04-28 23:45:31 +02:00
|
|
|
static GenericList *next_list(Visitor *v, GenericList *tail, size_t size)
|
2014-06-10 13:15:28 +02:00
|
|
|
{
|
2016-01-29 14:48:38 +01:00
|
|
|
StringOutputVisitor *sov = to_sov(v);
|
qapi: Simplify semantics of visit_next_list()
The semantics of the list visit are somewhat baroque, with the
following pseudocode when FooList is used:
start()
for (prev = head; cur = next(prev); prev = &cur) {
visit(&cur->value)
}
Note that these semantics (advance before visit) requires that
the first call to next() return the list head, while all other
calls return the next element of the list; that is, every visitor
implementation is required to track extra state to decide whether
to return the input as-is, or to advance. It also requires an
argument of 'GenericList **' to next(), solely because the first
iteration might need to modify the caller's GenericList head, so
that all other calls have to do a layer of dereferencing.
Thankfully, we only have two uses of list visits in the entire
code base: one in spapr_drc (which completely avoids
visit_next_list(), feeding in integers from a different source
than uint8List), and one in qapi-visit.py. That is, all other
list visitors are generated in qapi-visit.c, and share the same
paradigm based on a qapi FooList type, so we can refactor how
lists are laid out with minimal churn among clients.
We can greatly simplify things by hoisting the special case
into the start() routine, and flipping the order in the loop
to visit before advance:
start(head)
for (tail = *head; tail; tail = next(tail)) {
visit(&tail->value)
}
With the simpler semantics, visitors have less state to track,
the argument to next() is reduced to 'GenericList *', and it
also becomes obvious whether an input visitor is allocating a
FooList during visit_start_list() (rather than the old way of
not knowing if an allocation happened until the first
visit_next_list()). As a minor drawback, we now allocate in
two functions instead of one, and have to pass the size to
both functions (unless we were to tweak the input visitors to
cache the size to start_list for reuse during next_list, but
that defeats the goal of less visitor state).
The signature of visit_start_list() is chosen to match
visit_start_struct(), with the new parameters after 'name'.
The spapr_drc case is a virtual visit, done by passing NULL for
list, similarly to how NULL is passed to visit_start_struct()
when a qapi type is not used in those visits. It was easy to
provide these semantics for qmp-output and dealloc visitors,
and a bit harder for qmp-input (several prerequisite patches
refactored things to make this patch straightforward). But it
turned out that the string and opts visitors munge enough other
state during visit_next_list() to make it easier to just
document and require a GenericList visit for now; an assertion
will remind us to adjust things if we need the semantics in the
future.
Several pre-requisite cleanup patches made the reshuffling of
the various visitors easier; particularly the qmp input visitor.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-24-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-04-28 23:45:31 +02:00
|
|
|
GenericList *ret = tail->next;
|
2014-06-10 13:15:28 +02:00
|
|
|
|
qapi: Simplify semantics of visit_next_list()
The semantics of the list visit are somewhat baroque, with the
following pseudocode when FooList is used:
start()
for (prev = head; cur = next(prev); prev = &cur) {
visit(&cur->value)
}
Note that these semantics (advance before visit) requires that
the first call to next() return the list head, while all other
calls return the next element of the list; that is, every visitor
implementation is required to track extra state to decide whether
to return the input as-is, or to advance. It also requires an
argument of 'GenericList **' to next(), solely because the first
iteration might need to modify the caller's GenericList head, so
that all other calls have to do a layer of dereferencing.
Thankfully, we only have two uses of list visits in the entire
code base: one in spapr_drc (which completely avoids
visit_next_list(), feeding in integers from a different source
than uint8List), and one in qapi-visit.py. That is, all other
list visitors are generated in qapi-visit.c, and share the same
paradigm based on a qapi FooList type, so we can refactor how
lists are laid out with minimal churn among clients.
We can greatly simplify things by hoisting the special case
into the start() routine, and flipping the order in the loop
to visit before advance:
start(head)
for (tail = *head; tail; tail = next(tail)) {
visit(&tail->value)
}
With the simpler semantics, visitors have less state to track,
the argument to next() is reduced to 'GenericList *', and it
also becomes obvious whether an input visitor is allocating a
FooList during visit_start_list() (rather than the old way of
not knowing if an allocation happened until the first
visit_next_list()). As a minor drawback, we now allocate in
two functions instead of one, and have to pass the size to
both functions (unless we were to tweak the input visitors to
cache the size to start_list for reuse during next_list, but
that defeats the goal of less visitor state).
The signature of visit_start_list() is chosen to match
visit_start_struct(), with the new parameters after 'name'.
The spapr_drc case is a virtual visit, done by passing NULL for
list, similarly to how NULL is passed to visit_start_struct()
when a qapi type is not used in those visits. It was easy to
provide these semantics for qmp-output and dealloc visitors,
and a bit harder for qmp-input (several prerequisite patches
refactored things to make this patch straightforward). But it
turned out that the string and opts visitors munge enough other
state during visit_next_list() to make it easier to just
document and require a GenericList visit for now; an assertion
will remind us to adjust things if we need the semantics in the
future.
Several pre-requisite cleanup patches made the reshuffling of
the various visitors easier; particularly the qmp input visitor.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-24-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-04-28 23:45:31 +02:00
|
|
|
if (ret && !ret->next) {
|
|
|
|
sov->list_mode = LM_END;
|
2014-06-10 13:15:28 +02:00
|
|
|
}
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2016-01-29 14:48:59 +01:00
|
|
|
static void end_list(Visitor *v)
|
2014-06-10 13:15:28 +02:00
|
|
|
{
|
2016-01-29 14:48:38 +01:00
|
|
|
StringOutputVisitor *sov = to_sov(v);
|
2014-06-10 13:15:28 +02:00
|
|
|
|
|
|
|
assert(sov->list_mode == LM_STARTED ||
|
|
|
|
sov->list_mode == LM_END ||
|
|
|
|
sov->list_mode == LM_NONE ||
|
|
|
|
sov->list_mode == LM_IN_PROGRESS);
|
|
|
|
sov->list_mode = LM_NONE;
|
|
|
|
}
|
|
|
|
|
2012-02-09 09:36:37 +01:00
|
|
|
char *string_output_get_string(StringOutputVisitor *sov)
|
|
|
|
{
|
2014-06-10 13:15:28 +02:00
|
|
|
char *string = g_string_free(sov->string, false);
|
2012-02-09 09:36:37 +01:00
|
|
|
sov->string = NULL;
|
|
|
|
return string;
|
|
|
|
}
|
|
|
|
|
|
|
|
Visitor *string_output_get_visitor(StringOutputVisitor *sov)
|
|
|
|
{
|
|
|
|
return &sov->visitor;
|
|
|
|
}
|
|
|
|
|
2014-06-16 17:07:03 +02:00
|
|
|
static void free_range(void *range, void *dummy)
|
|
|
|
{
|
|
|
|
g_free(range);
|
|
|
|
}
|
|
|
|
|
2012-02-09 09:36:37 +01:00
|
|
|
void string_output_visitor_cleanup(StringOutputVisitor *sov)
|
|
|
|
{
|
2014-06-10 13:15:28 +02:00
|
|
|
if (sov->string) {
|
|
|
|
g_string_free(sov->string, true);
|
|
|
|
}
|
|
|
|
|
2014-06-16 17:07:03 +02:00
|
|
|
g_list_foreach(sov->ranges, free_range, NULL);
|
|
|
|
g_list_free(sov->ranges);
|
2012-02-09 09:36:37 +01:00
|
|
|
g_free(sov);
|
|
|
|
}
|
|
|
|
|
2014-02-08 11:01:50 +01:00
|
|
|
StringOutputVisitor *string_output_visitor_new(bool human)
|
2012-02-09 09:36:37 +01:00
|
|
|
{
|
|
|
|
StringOutputVisitor *v;
|
|
|
|
|
|
|
|
v = g_malloc0(sizeof(*v));
|
|
|
|
|
2014-06-10 13:15:28 +02:00
|
|
|
v->string = g_string_new(NULL);
|
2014-02-08 11:01:50 +01:00
|
|
|
v->human = human;
|
2016-04-28 23:45:09 +02:00
|
|
|
v->visitor.type = VISITOR_OUTPUT;
|
qapi: Prefer type_int64 over type_int in visitors
The qapi builtin type 'int' is basically shorthand for the type
'int64'. In fact, since no visitor was providing the optional
type_int64() callback, visit_type_int64() was just always falling
back to type_int(), cementing the equivalence between the types.
However, some visitors are providing a type_uint64() callback.
For purposes of code consistency, it is nicer if all visitors
use the paired type_int64/type_uint64 names rather than the
mismatched type_int/type_uint64. So this patch just renames
the signed int callbacks in place, dropping the type_int()
callback as redundant, and a later patch will focus on the
unsigned int callbacks.
Add some FIXMEs to questionable reuse of errp in code touched
by the rename, while at it (the reuse works as long as the
callbacks don't modify value when setting an error, but it's not
a good example to set) - a later patch will then fix those.
No change in functionality here, although further cleanups are
in the pipeline.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-14-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-01-29 14:48:49 +01:00
|
|
|
v->visitor.type_int64 = print_type_int64;
|
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.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-15-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-01-29 14:48:50 +01:00
|
|
|
v->visitor.type_uint64 = print_type_uint64;
|
2014-02-08 11:01:50 +01:00
|
|
|
v->visitor.type_size = print_type_size;
|
2012-02-09 09:36:37 +01:00
|
|
|
v->visitor.type_bool = print_type_bool;
|
|
|
|
v->visitor.type_str = print_type_str;
|
|
|
|
v->visitor.type_number = print_type_number;
|
2014-06-10 13:15:28 +02:00
|
|
|
v->visitor.start_list = start_list;
|
|
|
|
v->visitor.next_list = next_list;
|
|
|
|
v->visitor.end_list = end_list;
|
2012-02-09 09:36:37 +01:00
|
|
|
|
|
|
|
return v;
|
|
|
|
}
|