json: add APIs for quickly inserting hex blobs into as JSON strings

This is similar to the base64 support, but fixed-size hash values are
typically preferably presented as series of hex values, hence store them
here like that too.
This commit is contained in:
Lennart Poettering 2020-12-01 13:45:32 +01:00
parent 1403d48d61
commit 2d64d2b955
2 changed files with 55 additions and 0 deletions

View File

@ -433,6 +433,19 @@ int json_variant_new_base64(JsonVariant **ret, const void *p, size_t n) {
return json_variant_new_stringn(ret, s, k);
}
int json_variant_new_hex(JsonVariant **ret, const void *p, size_t n) {
_cleanup_free_ char *s = NULL;
assert_return(ret, -EINVAL);
assert_return(n == 0 || p, -EINVAL);
s = hexmem(p, n);
if (!s)
return -ENOMEM;
return json_variant_new_stringn(ret, s, n*2);
}
int json_variant_new_id128(JsonVariant **ret, sd_id128_t id) {
char s[SD_ID128_STRING_MAX];
@ -3603,6 +3616,36 @@ int json_buildv(JsonVariant **ret, va_list ap) {
break;
}
case _JSON_BUILD_HEX: {
const void *p;
size_t n;
if (!IN_SET(current->expect, EXPECT_TOPLEVEL, EXPECT_OBJECT_VALUE, EXPECT_ARRAY_ELEMENT)) {
r = -EINVAL;
goto finish;
}
p = va_arg(ap, const void *);
n = va_arg(ap, size_t);
if (current->n_suppress == 0) {
r = json_variant_new_hex(&add, p, n);
if (r < 0)
goto finish;
}
n_subtract = 1;
if (current->expect == EXPECT_TOPLEVEL)
current->expect = EXPECT_END;
else if (current->expect == EXPECT_OBJECT_VALUE)
current->expect = EXPECT_OBJECT_KEY;
else
assert(current->expect == EXPECT_ARRAY_ELEMENT);
break;
}
case _JSON_BUILD_ID128: {
sd_id128_t id;
@ -4405,6 +4448,14 @@ int json_variant_unbase64(JsonVariant *v, void **ret, size_t *ret_size) {
return unbase64mem(json_variant_string(v), (size_t) -1, ret, ret_size);
}
int json_variant_unhex(JsonVariant *v, void **ret, size_t *ret_size) {
if (!json_variant_is_string(v))
return -EINVAL;
return unhexmem(json_variant_string(v), (size_t) -1, ret, ret_size);
}
static const char* const json_variant_type_table[_JSON_VARIANT_TYPE_MAX] = {
[JSON_VARIANT_STRING] = "string",
[JSON_VARIANT_INTEGER] = "integer",

View File

@ -58,6 +58,7 @@ typedef enum JsonVariantType {
int json_variant_new_stringn(JsonVariant **ret, const char *s, size_t n);
int json_variant_new_base64(JsonVariant **ret, const void *p, size_t n);
int json_variant_new_hex(JsonVariant **ret, const void *p, size_t n);
int json_variant_new_integer(JsonVariant **ret, intmax_t i);
int json_variant_new_unsigned(JsonVariant **ret, uintmax_t u);
int json_variant_new_real(JsonVariant **ret, long double d);
@ -227,6 +228,7 @@ enum {
_JSON_BUILD_LITERAL,
_JSON_BUILD_STRV,
_JSON_BUILD_BASE64,
_JSON_BUILD_HEX,
_JSON_BUILD_ID128,
_JSON_BUILD_BYTE_ARRAY,
_JSON_BUILD_MAX,
@ -249,6 +251,7 @@ enum {
#define JSON_BUILD_LITERAL(l) _JSON_BUILD_LITERAL, ({ const char *_x = l; _x; })
#define JSON_BUILD_STRV(l) _JSON_BUILD_STRV, ({ char **_x = l; _x; })
#define JSON_BUILD_BASE64(p, n) _JSON_BUILD_BASE64, ({ const void *_x = p; _x; }), ({ size_t _y = n; _y; })
#define JSON_BUILD_HEX(p, n) _JSON_BUILD_HEX, ({ const void *_x = p; _x; }), ({ size_t _y = n; _y; })
#define JSON_BUILD_ID128(id) _JSON_BUILD_ID128, ({ sd_id128_t _x = id; _x; })
#define JSON_BUILD_BYTE_ARRAY(v, n) _JSON_BUILD_BYTE_ARRAY, ({ const void *_x = v; _x; }), ({ size_t _y = n; _y; })
@ -351,6 +354,7 @@ int json_log_internal(JsonVariant *variant, int level, int error, const char *fi
})
int json_variant_unbase64(JsonVariant *v, void **ret, size_t *ret_size);
int json_variant_unhex(JsonVariant *v, void **ret, size_t *ret_size);
const char *json_variant_type_to_string(JsonVariantType t);
JsonVariantType json_variant_type_from_string(const char *s);