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/* JSON core and helpers */
#include "json.h"
#include "json_escaped.h"
#include <assert.h>
#include <ccan/build_assert/build_assert.h>
#include <ccan/str/hex/hex.h>
#include <ccan/tal/str/str.h>
#include <errno.h>
#include <inttypes.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
struct json_result {
/* tal_arr of types we're enclosed in. */
jsmntype_t *wrapping;
/* tal_count() of this is strlen() + 1 */
char *s;
};
const char *json_tok_contents(const char *buffer, const jsmntok_t *t)
{
if (t->type == JSMN_STRING)
return buffer + t->start - 1;
return buffer + t->start;
}
/* Include " if it's a string. */
int json_tok_len(const jsmntok_t *t)
{
if (t->type == JSMN_STRING)
return t->end - t->start + 2;
return t->end - t->start;
}
bool json_tok_streq(const char *buffer, const jsmntok_t *tok, const char *str)
{
if (tok->type != JSMN_STRING)
return false;
if (tok->end - tok->start != strlen(str))
return false;
return strncmp(buffer + tok->start, str, tok->end - tok->start) == 0;
}
bool json_to_u64(const char *buffer, const jsmntok_t *tok,
uint64_t *num)
{
char *end;
unsigned long long l;
l = strtoull(buffer + tok->start, &end, 0);
if (end != buffer + tok->end)
return false;
BUILD_ASSERT(sizeof(l) >= sizeof(*num));
*num = l;
/* Check for overflow */
if (l == ULLONG_MAX && errno == ERANGE)
return false;
if (*num != l)
return false;
return true;
}
bool json_to_double(const char *buffer, const jsmntok_t *tok, double *num)
{
char *end;
*num = strtod(buffer + tok->start, &end);
if (end != buffer + tok->end)
return false;
return true;
}
bool json_to_number(const char *buffer, const jsmntok_t *tok,
unsigned int *num)
{
uint64_t u64;
if (!json_to_u64(buffer, tok, &u64))
return false;
*num = u64;
/* Just in case it doesn't fit. */
if (*num != u64)
return false;
return true;
}
bool json_tok_bitcoin_amount(const char *buffer, const jsmntok_t *tok,
uint64_t *satoshi)
{
char *end;
unsigned long btc, sat;
btc = strtoul(buffer + tok->start, &end, 10);
if (btc == ULONG_MAX && errno == ERANGE)
return false;
if (end != buffer + tok->end) {
/* Expect always 8 decimal places. */
if (*end != '.' || buffer + tok->end - end != 9)
return false;
sat = strtoul(end+1, &end, 10);
if (sat == ULONG_MAX && errno == ERANGE)
return false;
if (end != buffer + tok->end)
return false;
} else
sat = 0;
*satoshi = btc * (uint64_t)100000000 + sat;
if (*satoshi != btc * (uint64_t)100000000 + sat)
return false;
return true;
}
bool json_tok_is_num(const char *buffer, const jsmntok_t *tok)
{
if (tok->type != JSMN_PRIMITIVE)
return false;
for (int i = tok->start; i < tok->end; i++)
if (!cisdigit(buffer[i]))
return false;
return true;
}
bool json_tok_is_null(const char *buffer, const jsmntok_t *tok)
{
if (tok->type != JSMN_PRIMITIVE)
return false;
return buffer[tok->start] == 'n';
}
const jsmntok_t *json_next(const jsmntok_t *tok)
{
const jsmntok_t *t;
size_t i;
for (t = tok + 1, i = 0; i < tok->size; i++)
t = json_next(t);
return t;
}
const jsmntok_t *json_get_member(const char *buffer, const jsmntok_t tok[],
const char *label)
{
const jsmntok_t *t, *end;
if (tok->type != JSMN_OBJECT)
return NULL;
end = json_next(tok);
for (t = tok + 1; t < end; t = json_next(t+1))
if (json_tok_streq(buffer, t, label))
return t + 1;
return NULL;
}
const jsmntok_t *json_get_arr(const jsmntok_t tok[], size_t index)
{
const jsmntok_t *t, *end;
if (tok->type != JSMN_ARRAY)
return NULL;
end = json_next(tok);
for (t = tok + 1; t < end; t = json_next(t)) {
if (index == 0)
return t;
index--;
}
return NULL;
}
jsmntok_t *json_parse_input(const char *input, int len, bool *valid)
{
jsmn_parser parser;
jsmntok_t *toks;
int ret;
toks = tal_arr(input, jsmntok_t, 10);
toks[0].type = JSMN_UNDEFINED;
jsmn_init(&parser);
again:
ret = jsmn_parse(&parser, input, len, toks, tal_count(toks) - 1);
switch (ret) {
case JSMN_ERROR_INVAL:
*valid = false;
return tal_free(toks);
case JSMN_ERROR_NOMEM:
tal_resize(&toks, tal_count(toks) * 2);
goto again;
}
/* Check whether we read at least one full root element, i.e., root
* element has its end set. */
if (toks[0].type == JSMN_UNDEFINED || toks[0].end == -1) {
*valid = true;
return tal_free(toks);
}
/* If we read a partial element at the end of the stream we'll get a
* ret=JSMN_ERROR_PART, but due to the previous check we know we read at
* least one full element, so count tokens that are part of this root
* element. */
ret = json_next(toks) - toks;
/* Cut to length and return. */
*valid = true;
tal_resize(&toks, ret + 1);
/* Make sure last one is always referenceable. */
toks[ret].type = -1;
toks[ret].start = toks[ret].end = toks[ret].size = 0;
return toks;
}
static void result_append(struct json_result *res, const char *str)
{
size_t len = tal_count(res->s) - 1;
tal_resize(&res->s, len + strlen(str) + 1);
strcpy(res->s + len, str);
}
static void PRINTF_FMT(2,3)
result_append_fmt(struct json_result *res, const char *fmt, ...)
{
size_t len = tal_count(res->s) - 1, fmtlen;
va_list ap;
va_start(ap, fmt);
fmtlen = vsnprintf(NULL, 0, fmt, ap);
va_end(ap);
tal_resize(&res->s, len + fmtlen + 1);
va_start(ap, fmt);
vsprintf(res->s + len, fmt, ap);
va_end(ap);
}
static bool result_ends_with(struct json_result *res, const char *str)
{
size_t len = tal_count(res->s) - 1;
if (strlen(str) > len)
return false;
return streq(res->s + len - strlen(str), str);
}
static void check_fieldname(const struct json_result *result,
const char *fieldname)
{
size_t n = tal_count(result->wrapping);
if (n == 0)
/* Can't have a fieldname if not in anything! */
assert(!fieldname);
else if (result->wrapping[n-1] == JSMN_ARRAY)
/* No fieldnames in arrays. */
assert(!fieldname);
else
/* Must have fieldnames in objects. */
assert(fieldname);
}
static void result_add_indent(struct json_result *result);
static void json_start_member(struct json_result *result, const char *fieldname)
{
/* Prepend comma if required. */
if (result->s[0]
&& !result_ends_with(result, "{")
&& !result_ends_with(result, "["))
result_append(result, ", \n");
else
result_append(result, "\n");
result_add_indent(result);
check_fieldname(result, fieldname);
if (fieldname)
result_append_fmt(result, "\"%s\": ", fieldname);
}
static void result_add_indent(struct json_result *result)
{
size_t i, indent = tal_count(result->wrapping);
if (!indent)
return;
for (i = 0; i < indent; i++)
result_append(result, " ");
}
static void result_add_wrap(struct json_result *result, jsmntype_t type)
{
size_t indent = tal_count(result->wrapping);
tal_resize(&result->wrapping, indent+1);
result->wrapping[indent] = type;
}
static void result_pop_wrap(struct json_result *result, jsmntype_t type)
{
size_t indent = tal_count(result->wrapping);
assert(indent);
assert(result->wrapping[indent-1] == type);
tal_resize(&result->wrapping, indent-1);
}
void json_array_start(struct json_result *result, const char *fieldname)
{
json_start_member(result, fieldname);
result_append(result, "[");
result_add_wrap(result, JSMN_ARRAY);
}
void json_array_end(struct json_result *result)
{
result_append(result, "\n");
result_pop_wrap(result, JSMN_ARRAY);
result_add_indent(result);
result_append(result, "]");
}
void json_object_start(struct json_result *result, const char *fieldname)
{
json_start_member(result, fieldname);
result_append(result, "{");
result_add_wrap(result, JSMN_OBJECT);
}
void json_object_end(struct json_result *result)
{
result_append(result, "\n");
result_pop_wrap(result, JSMN_OBJECT);
result_add_indent(result);
result_append(result, "}");
}
void json_add_num(struct json_result *result, const char *fieldname, unsigned int value)
{
json_start_member(result, fieldname);
result_append_fmt(result, "%u", value);
}
void json_add_double(struct json_result *result, const char *fieldname, double value)
{
json_start_member(result, fieldname);
result_append_fmt(result, "%f", value);
}
void json_add_u64(struct json_result *result, const char *fieldname,
uint64_t value)
{
json_start_member(result, fieldname);
result_append_fmt(result, "%"PRIu64, value);
}
void json_add_literal(struct json_result *result, const char *fieldname,
const char *literal, int len)
{
json_start_member(result, fieldname);
result_append_fmt(result, "%.*s", len, literal);
}
void json_add_string(struct json_result *result, const char *fieldname, const char *value)
{
struct json_escaped *esc = json_partial_escape(NULL, value);
json_start_member(result, fieldname);
result_append_fmt(result, "\"%s\"", esc->s);
tal_free(esc);
}
void json_add_bool(struct json_result *result, const char *fieldname, bool value)
{
json_start_member(result, fieldname);
result_append(result, value ? "true" : "false");
}
void json_add_hex(struct json_result *result, const char *fieldname,
const void *data, size_t len)
{
char *hex = tal_arr(NULL, char, hex_str_size(len));
hex_encode(data, len, hex, hex_str_size(len));
json_add_string(result, fieldname, hex);
tal_free(hex);
}
void json_add_hex_talarr(struct json_result *result,
const char *fieldname,
const tal_t *data)
{
json_add_hex(result, fieldname, data, tal_bytelen(data));
}
void json_add_object(struct json_result *result, ...)
{
va_list ap;
const char *field;
va_start(ap, result);
json_object_start(result, NULL);
while ((field = va_arg(ap, const char *)) != NULL) {
jsmntype_t type = va_arg(ap, jsmntype_t);
const char *value = va_arg(ap, const char *);
if (type == JSMN_STRING)
json_add_string(result, field, value);
else
json_add_literal(result, field, value, strlen(value));
}
json_object_end(result);
va_end(ap);
}
void json_add_escaped_string(struct json_result *result, const char *fieldname,
const struct json_escaped *esc TAKES)
{
json_start_member(result, fieldname);
result_append_fmt(result, "\"%s\"", esc->s);
if (taken(esc))
tal_free(esc);
}
struct json_result *new_json_result(const tal_t *ctx)
{
struct json_result *r = tal(ctx, struct json_result);
/* Using tal_arr means that it has a valid count. */
r->s = tal_arrz(r, char, 1);
r->wrapping = tal_arr(r, jsmntype_t, 0);
return r;
}
const char *json_result_string(const struct json_result *result)
{
assert(tal_count(result->wrapping) == 0);
assert(tal_count(result->s) == strlen(result->s) + 1);
return result->s;
}