json: use fpclassify() or its helper functions

This commit is contained in:
Yu Watanabe 2022-07-19 04:30:59 +09:00
parent fbccfa95c4
commit 1561db8ac2
3 changed files with 28 additions and 38 deletions

View file

@ -87,10 +87,6 @@
_Pragma("GCC diagnostic push")
#endif
#define DISABLE_WARNING_FLOAT_EQUAL \
_Pragma("GCC diagnostic push"); \
_Pragma("GCC diagnostic ignored \"-Wfloat-equal\"")
#define DISABLE_WARNING_TYPE_LIMITS \
_Pragma("GCC diagnostic push"); \
_Pragma("GCC diagnostic ignored \"-Wtype-limits\"")

View file

@ -2,7 +2,6 @@
#include <errno.h>
#include <locale.h>
#include <math.h>
#include <stdarg.h>
#include <stdlib.h>
#include <sys/types.h>
@ -18,6 +17,7 @@
#include "json-internal.h"
#include "json.h"
#include "macro.h"
#include "math-util.h"
#include "memory-util.h"
#include "string-table.h"
#include "string-util.h"
@ -253,9 +253,7 @@ static JsonVariant *json_variant_formalize(JsonVariant *v) {
return json_variant_unsigned(v) == 0 ? JSON_VARIANT_MAGIC_ZERO_UNSIGNED : v;
case JSON_VARIANT_REAL:
DISABLE_WARNING_FLOAT_EQUAL;
return json_variant_real(v) == 0.0 ? JSON_VARIANT_MAGIC_ZERO_REAL : v;
REENABLE_WARNING;
return iszero_safe(json_variant_real(v)) ? JSON_VARIANT_MAGIC_ZERO_REAL : v;
case JSON_VARIANT_STRING:
return isempty(json_variant_string(v)) ? JSON_VARIANT_MAGIC_EMPTY_STRING : v;
@ -352,17 +350,17 @@ int json_variant_new_real(JsonVariant **ret, double d) {
assert_return(ret, -EINVAL);
DISABLE_WARNING_FLOAT_EQUAL;
if (d == 0.0) {
*ret = JSON_VARIANT_MAGIC_ZERO_REAL;
return 0;
}
REENABLE_WARNING;
/* JSON doesn't know NaN, +Infinity or -Infinity. Let's silently convert to 'null'. */
if (isnan(d) || isinf(d)) {
r = fpclassify(d);
switch (r) {
case FP_NAN:
case FP_INFINITE:
/* JSON doesn't know NaN, +Infinity or -Infinity. Let's silently convert to 'null'. */
*ret = JSON_VARIANT_MAGIC_NULL;
return 0;
case FP_ZERO:
*ret = JSON_VARIANT_MAGIC_ZERO_REAL;
return 0;
}
r = json_variant_new(&v, JSON_VARIANT_REAL, sizeof(d));
@ -914,10 +912,8 @@ int64_t json_variant_integer(JsonVariant *v) {
converted = (int64_t) v->value.real;
DISABLE_WARNING_FLOAT_EQUAL;
if ((double) converted == v->value.real)
if (fp_equal((double) converted, v->value.real))
return converted;
REENABLE_WARNING;
log_debug("Real %g requested as integer, and cannot be converted losslessly, returning 0.", v->value.real);
return 0;
@ -961,10 +957,8 @@ uint64_t json_variant_unsigned(JsonVariant *v) {
converted = (uint64_t) v->value.real;
DISABLE_WARNING_FLOAT_EQUAL;
if ((double) converted == v->value.real)
if (fp_equal((double) converted, v->value.real))
return converted;
REENABLE_WARNING;
log_debug("Real %g requested as unsigned integer, and cannot be converted losslessly, returning 0.", v->value.real);
return 0;
@ -1153,15 +1147,11 @@ bool json_variant_has_type(JsonVariant *v, JsonVariantType type) {
if (rt == JSON_VARIANT_UNSIGNED && type == JSON_VARIANT_REAL)
return (uint64_t) (double) v->value.unsig == v->value.unsig;
DISABLE_WARNING_FLOAT_EQUAL;
/* Any real that can be converted losslessly to an integer and back may also be considered an integer */
if (rt == JSON_VARIANT_REAL && type == JSON_VARIANT_INTEGER)
return (double) (int64_t) v->value.real == v->value.real;
return fp_equal((double) (int64_t) v->value.real, v->value.real);
if (rt == JSON_VARIANT_REAL && type == JSON_VARIANT_UNSIGNED)
return (double) (uint64_t) v->value.real == v->value.real;
REENABLE_WARNING;
return fp_equal((double) (uint64_t) v->value.real, v->value.real);
return false;
}
@ -1314,9 +1304,7 @@ bool json_variant_equal(JsonVariant *a, JsonVariant *b) {
return json_variant_unsigned(a) == json_variant_unsigned(b);
case JSON_VARIANT_REAL:
DISABLE_WARNING_FLOAT_EQUAL;
return json_variant_real(a) == json_variant_real(b);
REENABLE_WARNING;
return fp_equal(json_variant_real(a), json_variant_real(b));
case JSON_VARIANT_BOOLEAN:
return json_variant_boolean(a) == json_variant_boolean(b);

View file

@ -1,7 +1,6 @@
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#include <float.h>
#include <math.h>
#include "alloc-util.h"
#include "escape.h"
@ -9,6 +8,7 @@
#include "fileio.h"
#include "json-internal.h"
#include "json.h"
#include "math-util.h"
#include "string-util.h"
#include "strv.h"
#include "tests.h"
@ -239,9 +239,7 @@ static void test_zeroes(JsonVariant *v) {
assert_se(json_variant_integer(w) == 0);
assert_se(json_variant_unsigned(w) == 0U);
DISABLE_WARNING_FLOAT_EQUAL;
assert_se(json_variant_real(w) == 0.0L);
REENABLE_WARNING;
assert_se(iszero_safe(json_variant_real(w)));
assert_se(json_variant_is_integer(w));
assert_se(json_variant_is_unsigned(w));
@ -511,7 +509,7 @@ static void test_float_match(JsonVariant *v) {
const double delta = 0.0001;
assert_se(json_variant_is_array(v));
assert_se(json_variant_elements(v) == 9);
assert_se(json_variant_elements(v) == 11);
assert_se(fabs(1.0 - (DBL_MIN / json_variant_real(json_variant_by_index(v, 0)))) <= delta);
assert_se(fabs(1.0 - (DBL_MAX / json_variant_real(json_variant_by_index(v, 1)))) <= delta);
assert_se(json_variant_is_null(json_variant_by_index(v, 2))); /* nan is not supported by json → null */
@ -528,6 +526,12 @@ static void test_float_match(JsonVariant *v) {
assert_se(json_variant_is_real(json_variant_by_index(v, 8)) &&
json_variant_is_integer(json_variant_by_index(v, 8)) &&
json_variant_integer(json_variant_by_index(v, 8)) == -10);
assert_se(json_variant_is_real(json_variant_by_index(v, 9)) &&
!json_variant_is_integer(json_variant_by_index(v, 9)));
assert_se(fabs(1.0 - (DBL_MIN / 2 / json_variant_real(json_variant_by_index(v, 9)))) <= delta);
assert_se(json_variant_is_real(json_variant_by_index(v, 10)) &&
!json_variant_is_integer(json_variant_by_index(v, 10)));
assert_se(fabs(1.0 - (-DBL_MIN / 2 / json_variant_real(json_variant_by_index(v, 10)))) <= delta);
}
TEST(float) {
@ -543,7 +547,9 @@ TEST(float) {
JSON_BUILD_REAL(HUGE_VAL),
JSON_BUILD_REAL(0),
JSON_BUILD_REAL(10),
JSON_BUILD_REAL(-10))) >= 0);
JSON_BUILD_REAL(-10),
JSON_BUILD_REAL(DBL_MIN / 2),
JSON_BUILD_REAL(-DBL_MIN / 2))) >= 0);
json_variant_dump(v, JSON_FORMAT_COLOR|JSON_FORMAT_PRETTY, NULL, NULL);