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ea88e40 Jan 13, 2017
@cpq @mmikulicic @dimonomid @Kira-sempai @w-vi @rojer
995 lines (904 sloc) 28.5 KB
/*
* Copyright (c) 2004-2013 Sergey Lyubka <valenok@gmail.com>
* Copyright (c) 2013 Cesanta Software Limited
* All rights reserved
*
* This library is dual-licensed: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation. For the terms of this
* license, see <http: *www.gnu.org/licenses/>.
*
* You are free to use this library under the terms of the GNU General
* Public License, but WITHOUT ANY WARRANTY; without even the implied
* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details.
*
* Alternatively, you can license this library under a commercial
* license, as set out in <http://cesanta.com/products.html>.
*/
#define _CRT_SECURE_NO_WARNINGS /* Disable deprecation warning in VS2005+ */
#include "frozen.h"
#include <ctype.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#if !defined(WEAK)
#if (defined(__GNUC__) || defined(__TI_COMPILER_VERSION__)) && !defined(_WIN32)
#define WEAK __attribute__((weak))
#else
#define WEAK
#endif
#endif
#ifdef _WIN32
#define snprintf cs_win_snprintf
#define vsnprintf cs_win_vsnprintf
int cs_win_snprintf(char *str, size_t size, const char *format, ...);
int cs_win_vsnprintf(char *str, size_t size, const char *format, va_list ap);
#if _MSC_VER >= 1700
#include <stdint.h>
#else
typedef _int64 int64_t;
typedef unsigned _int64 uint64_t;
#endif
#define PRId64 "I64d"
#define PRIu64 "I64u"
#if !defined(SIZE_T_FMT)
#if _MSC_VER >= 1310
#define SIZE_T_FMT "Iu"
#else
#define SIZE_T_FMT "u"
#endif
#endif
#else /* _WIN32 */
/* <inttypes.h> wants this for C++ */
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
#if !defined(SIZE_T_FMT)
#define SIZE_T_FMT "zu"
#endif
#endif /* _WIN32 */
#define INT64_FMT PRId64
#define UINT64_FMT PRIu64
#ifndef va_copy
#define va_copy(x, y) x = y
#endif
#ifndef JSON_MAX_PATH_LEN
#define JSON_MAX_PATH_LEN 60
#endif
struct frozen {
const char *end;
const char *cur;
const char *cur_name;
size_t cur_name_len;
/* For callback API */
char path[JSON_MAX_PATH_LEN];
int path_len;
void *callback_data;
json_walk_callback_t callback;
};
struct fstate {
const char *ptr;
int path_len;
};
#define SET_STATE(fr, ptr, str, len) \
struct fstate fstate = {(ptr), (fr)->path_len}; \
append_to_path((fr), (str), (len));
#define CALL_BACK(fr, tok, value, len) \
do { \
if ((fr)->callback && \
((fr)->path_len == 0 || (fr)->path[(fr)->path_len - 1] != '.')) { \
struct json_token t = {(value), (len), (tok)}; \
\
/* Call the callback with the given value and current name */ \
(fr)->callback((fr)->callback_data, (fr)->cur_name, (fr)->cur_name_len, \
(fr)->path, &t); \
\
/* Reset the name */ \
(fr)->cur_name = NULL; \
(fr)->cur_name_len = 0; \
} \
} while (0)
static int append_to_path(struct frozen *f, const char *str, int size) {
int n = f->path_len;
f->path_len +=
snprintf(f->path + f->path_len, sizeof(f->path) - (f->path_len + 1),
"%.*s", size, str);
return n;
}
static void truncate_path(struct frozen *f, int len) {
f->path_len = len;
f->path[len] = '\0';
}
static int parse_object(struct frozen *f);
static int parse_value(struct frozen *f);
#define EXPECT(cond, err_code) \
do { \
if (!(cond)) return (err_code); \
} while (0)
#define TRY(expr) \
do { \
int _n = expr; \
if (_n < 0) return _n; \
} while (0)
#define END_OF_STRING (-1)
static int left(const struct frozen *f) {
return f->end - f->cur;
}
static int is_space(int ch) {
return ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n';
}
static void skip_whitespaces(struct frozen *f) {
while (f->cur < f->end && is_space(*f->cur)) f->cur++;
}
static int cur(struct frozen *f) {
skip_whitespaces(f);
return f->cur >= f->end ? END_OF_STRING : *(unsigned char *) f->cur;
}
static int test_and_skip(struct frozen *f, int expected) {
int ch = cur(f);
if (ch == expected) {
f->cur++;
return 0;
}
return ch == END_OF_STRING ? JSON_STRING_INCOMPLETE : JSON_STRING_INVALID;
}
static int is_alpha(int ch) {
return (ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z');
}
static int is_digit(int ch) {
return ch >= '0' && ch <= '9';
}
static int is_hex_digit(int ch) {
return is_digit(ch) || (ch >= 'a' && ch <= 'f') || (ch >= 'A' && ch <= 'F');
}
static int get_escape_len(const char *s, int len) {
switch (*s) {
case 'u':
return len < 6 ? JSON_STRING_INCOMPLETE
: is_hex_digit(s[1]) && is_hex_digit(s[2]) &&
is_hex_digit(s[3]) && is_hex_digit(s[4])
? 5
: JSON_STRING_INVALID;
case '"':
case '\\':
case '/':
case 'b':
case 'f':
case 'n':
case 'r':
case 't':
return len < 2 ? JSON_STRING_INCOMPLETE : 1;
default:
return JSON_STRING_INVALID;
}
}
/* identifier = letter { letter | digit | '_' } */
static int parse_identifier(struct frozen *f) {
EXPECT(is_alpha(cur(f)), JSON_STRING_INVALID);
{
SET_STATE(f, f->cur, "", 0);
while (f->cur < f->end &&
(*f->cur == '_' || is_alpha(*f->cur) || is_digit(*f->cur))) {
f->cur++;
}
truncate_path(f, fstate.path_len);
CALL_BACK(f, JSON_TYPE_STRING, fstate.ptr, f->cur - fstate.ptr);
}
return 0;
}
static int get_utf8_char_len(unsigned char ch) {
if ((ch & 0x80) == 0) return 1;
switch (ch & 0xf0) {
case 0xf0:
return 4;
case 0xe0:
return 3;
default:
return 2;
}
}
/* string = '"' { quoted_printable_chars } '"' */
static int parse_string(struct frozen *f) {
int n, ch = 0, len = 0;
TRY(test_and_skip(f, '"'));
{
SET_STATE(f, f->cur, "", 0);
for (; f->cur < f->end; f->cur += len) {
ch = *(unsigned char *) f->cur;
len = get_utf8_char_len((unsigned char) ch);
EXPECT(ch >= 32 && len > 0, JSON_STRING_INVALID); /* No control chars */
EXPECT(len < left(f), JSON_STRING_INCOMPLETE);
if (ch == '\\') {
EXPECT((n = get_escape_len(f->cur + 1, left(f))) > 0, n);
len += n;
} else if (ch == '"') {
truncate_path(f, fstate.path_len);
CALL_BACK(f, JSON_TYPE_STRING, fstate.ptr, f->cur - fstate.ptr);
f->cur++;
break;
};
}
}
return ch == '"' ? 0 : JSON_STRING_INCOMPLETE;
}
/* number = [ '-' ] digit+ [ '.' digit+ ] [ ['e'|'E'] ['+'|'-'] digit+ ] */
static int parse_number(struct frozen *f) {
int ch = cur(f);
SET_STATE(f, f->cur, "", 0);
if (ch == '-') f->cur++;
EXPECT(f->cur < f->end, JSON_STRING_INCOMPLETE);
EXPECT(is_digit(f->cur[0]), JSON_STRING_INVALID);
while (f->cur < f->end && is_digit(f->cur[0])) f->cur++;
if (f->cur < f->end && f->cur[0] == '.') {
f->cur++;
EXPECT(f->cur < f->end, JSON_STRING_INCOMPLETE);
EXPECT(is_digit(f->cur[0]), JSON_STRING_INVALID);
while (f->cur < f->end && is_digit(f->cur[0])) f->cur++;
}
if (f->cur < f->end && (f->cur[0] == 'e' || f->cur[0] == 'E')) {
f->cur++;
EXPECT(f->cur < f->end, JSON_STRING_INCOMPLETE);
if ((f->cur[0] == '+' || f->cur[0] == '-')) f->cur++;
EXPECT(f->cur < f->end, JSON_STRING_INCOMPLETE);
EXPECT(is_digit(f->cur[0]), JSON_STRING_INVALID);
while (f->cur < f->end && is_digit(f->cur[0])) f->cur++;
}
truncate_path(f, fstate.path_len);
CALL_BACK(f, JSON_TYPE_NUMBER, fstate.ptr, f->cur - fstate.ptr);
return 0;
}
/* array = '[' [ value { ',' value } ] ']' */
static int parse_array(struct frozen *f) {
int i = 0, current_path_len;
char buf[20];
TRY(test_and_skip(f, '['));
{
CALL_BACK(f, JSON_TYPE_ARRAY_START, NULL, 0);
{
SET_STATE(f, f->cur - 1, "", 0);
while (cur(f) != ']') {
snprintf(buf, sizeof(buf), "[%d]", i);
i++;
current_path_len = append_to_path(f, buf, strlen(buf));
f->cur_name =
f->path + strlen(f->path) - strlen(buf) + 1 /*opening brace*/;
f->cur_name_len = strlen(buf) - 2 /*braces*/;
TRY(parse_value(f));
truncate_path(f, current_path_len);
if (cur(f) == ',') f->cur++;
}
TRY(test_and_skip(f, ']'));
truncate_path(f, fstate.path_len);
CALL_BACK(f, JSON_TYPE_ARRAY_END, fstate.ptr, f->cur - fstate.ptr);
}
}
return 0;
}
static int expect(struct frozen *f, const char *s, int len,
enum json_token_type tok_type) {
int i, n = left(f);
SET_STATE(f, f->cur, "", 0);
for (i = 0; i < len; i++) {
if (i >= n) return JSON_STRING_INCOMPLETE;
if (f->cur[i] != s[i]) return JSON_STRING_INVALID;
}
f->cur += len;
truncate_path(f, fstate.path_len);
CALL_BACK(f, tok_type, fstate.ptr, f->cur - fstate.ptr);
return 0;
}
/* value = 'null' | 'true' | 'false' | number | string | array | object */
static int parse_value(struct frozen *f) {
int ch = cur(f);
switch (ch) {
case '"':
TRY(parse_string(f));
break;
case '{':
TRY(parse_object(f));
break;
case '[':
TRY(parse_array(f));
break;
case 'n':
TRY(expect(f, "null", 4, JSON_TYPE_NULL));
break;
case 't':
TRY(expect(f, "true", 4, JSON_TYPE_TRUE));
break;
case 'f':
TRY(expect(f, "false", 5, JSON_TYPE_FALSE));
break;
case '-':
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
TRY(parse_number(f));
break;
default:
return ch == END_OF_STRING ? JSON_STRING_INCOMPLETE : JSON_STRING_INVALID;
}
return 0;
}
/* key = identifier | string */
static int parse_key(struct frozen *f) {
int ch = cur(f);
#if 0
printf("%s [%.*s]\n", __func__, (int) (f->end - f->cur), f->cur);
#endif
if (is_alpha(ch)) {
TRY(parse_identifier(f));
} else if (ch == '"') {
TRY(parse_string(f));
} else {
return ch == END_OF_STRING ? JSON_STRING_INCOMPLETE : JSON_STRING_INVALID;
}
return 0;
}
/* pair = key ':' value */
static int parse_pair(struct frozen *f) {
int current_path_len;
const char *tok;
skip_whitespaces(f);
tok = f->cur;
TRY(parse_key(f));
{
f->cur_name = *tok == '"' ? tok + 1 : tok;
f->cur_name_len = *tok == '"' ? f->cur - tok - 2 : f->cur - tok;
current_path_len = append_to_path(f, f->cur_name, f->cur_name_len);
}
TRY(test_and_skip(f, ':'));
TRY(parse_value(f));
truncate_path(f, current_path_len);
return 0;
}
/* object = '{' pair { ',' pair } '}' */
static int parse_object(struct frozen *f) {
TRY(test_and_skip(f, '{'));
{
CALL_BACK(f, JSON_TYPE_OBJECT_START, NULL, 0);
{
SET_STATE(f, f->cur - 1, ".", 1);
while (cur(f) != '}') {
TRY(parse_pair(f));
if (cur(f) == ',') f->cur++;
}
TRY(test_and_skip(f, '}'));
truncate_path(f, fstate.path_len);
CALL_BACK(f, JSON_TYPE_OBJECT_END, fstate.ptr, f->cur - fstate.ptr);
}
}
return 0;
}
static int doit(struct frozen *f) {
if (f->cur == 0 || f->end < f->cur) return JSON_STRING_INVALID;
if (f->end == f->cur) return JSON_STRING_INCOMPLETE;
return parse_value(f);
}
static int json_encode_string(struct json_out *out, const char *p, size_t len) {
size_t i, cl, n = 0;
const char *hex_digits = "0123456789abcdef";
const char *specials = "btnvfr";
for (i = 0; i < len; i++) {
unsigned char ch = ((unsigned char *) p)[i];
if (ch == '"' || ch == '\\') {
n += out->printer(out, "\\", 1);
n += out->printer(out, p + i, 1);
} else if (ch >= '\b' && ch <= '\r') {
n += out->printer(out, "\\", 1);
n += out->printer(out, &specials[ch - '\b'], 1);
} else if (isprint(ch)) {
n += out->printer(out, p + i, 1);
} else if ((cl = get_utf8_char_len(ch)) == 1) {
n += out->printer(out, "\\u00", 4);
n += out->printer(out, &hex_digits[(ch >> 4) % 0xf], 1);
n += out->printer(out, &hex_digits[ch % 0xf], 1);
} else {
n += out->printer(out, p + i, cl);
i += cl - 1;
}
}
return n;
}
int json_printer_buf(struct json_out *out, const char *buf, size_t len) WEAK;
int json_printer_buf(struct json_out *out, const char *buf, size_t len) {
size_t avail = out->u.buf.size - out->u.buf.len;
size_t n = len < avail ? len : avail;
memcpy(out->u.buf.buf + out->u.buf.len, buf, n);
out->u.buf.len += n;
if (out->u.buf.size > 0) {
size_t idx = out->u.buf.len;
if (idx >= out->u.buf.size) idx = out->u.buf.size - 1;
out->u.buf.buf[idx] = '\0';
}
return len;
}
int json_printer_file(struct json_out *out, const char *buf, size_t len) WEAK;
int json_printer_file(struct json_out *out, const char *buf, size_t len) {
return fwrite(buf, 1, len, out->u.fp);
}
static int b64idx(int c) {
if (c < 26) {
return c + 'A';
} else if (c < 52) {
return c - 26 + 'a';
} else if (c < 62) {
return c - 52 + '0';
} else {
return c == 62 ? '+' : '/';
}
}
static int b64rev(int c) {
if (c >= 'A' && c <= 'Z') {
return c - 'A';
} else if (c >= 'a' && c <= 'z') {
return c + 26 - 'a';
} else if (c >= '0' && c <= '9') {
return c + 52 - '0';
} else if (c == '+') {
return 62;
} else if (c == '/') {
return 63;
} else {
return 64;
}
}
static uint8_t hexdec(const char *s) {
#define HEXTOI(x) (x >= '0' && x <= '9' ? x - '0' : x - 'W')
int a = tolower(*(const unsigned char *) s);
int b = tolower(*(const unsigned char *) (s + 1));
return (HEXTOI(a) << 4) | HEXTOI(b);
}
static int b64enc(struct json_out *out, const unsigned char *p, int n) {
char buf[4];
int i, len = 0;
for (i = 0; i < n; i += 3) {
int a = p[i], b = i + 1 < n ? p[i + 1] : 0, c = i + 2 < n ? p[i + 2] : 0;
buf[0] = b64idx(a >> 2);
buf[1] = b64idx((a & 3) << 4 | (b >> 4));
buf[2] = b64idx((b & 15) << 2 | (c >> 6));
buf[3] = b64idx(c & 63);
if (i + 1 >= n) buf[2] = '=';
if (i + 2 >= n) buf[3] = '=';
len += out->printer(out, buf, sizeof(buf));
}
return len;
}
static int b64dec(const char *src, int n, char *dst) {
const char *end = src + n;
int len = 0;
while (src + 3 < end) {
int a = b64rev(src[0]), b = b64rev(src[1]), c = b64rev(src[2]),
d = b64rev(src[3]);
dst[len++] = (a << 2) | (b >> 4);
if (src[2] != '=') {
dst[len++] = (b << 4) | (c >> 2);
if (src[3] != '=') {
dst[len++] = (c << 6) | d;
}
}
src += 4;
}
return len;
}
int json_vprintf(struct json_out *out, const char *fmt, va_list xap) WEAK;
int json_vprintf(struct json_out *out, const char *fmt, va_list xap) {
int len = 0;
const char *quote = "\"", *null = "null";
va_list ap;
va_copy(ap, xap);
while (*fmt != '\0') {
if (strchr(":, \r\n\t[]{}\"", *fmt) != NULL) {
len += out->printer(out, fmt, 1);
fmt++;
} else if (fmt[0] == '%') {
char buf[21];
size_t skip = 2;
if (fmt[1] == 'l' && fmt[2] == 'l' && (fmt[3] == 'd' || fmt[3] == 'u')) {
int64_t val = va_arg(ap, int64_t);
const char *fmt2 = fmt[3] == 'u' ? "%" UINT64_FMT : "%" INT64_FMT;
snprintf(buf, sizeof(buf), fmt2, val);
len += out->printer(out, buf, strlen(buf));
skip += 2;
} else if (fmt[1] == 'z' && fmt[2] == 'u') {
size_t val = va_arg(ap, size_t);
snprintf(buf, sizeof(buf), "%" SIZE_T_FMT, val);
len += out->printer(out, buf, strlen(buf));
skip += 1;
} else if (fmt[1] == 'M') {
json_printf_callback_t f = va_arg(ap, json_printf_callback_t);
len += f(out, &ap);
} else if (fmt[1] == 'B') {
int val = va_arg(ap, int);
const char *str = val ? "true" : "false";
len += out->printer(out, str, strlen(str));
} else if (fmt[1] == 'H') {
const char *hex = "0123456789abcdef";
int i, n = va_arg(ap, int);
const unsigned char *p = va_arg(ap, const unsigned char *);
len += out->printer(out, quote, 1);
for (i = 0; i < n; i++) {
len += out->printer(out, &hex[(p[i] >> 4) & 0xf], 1);
len += out->printer(out, &hex[p[i] & 0xf], 1);
}
len += out->printer(out, quote, 1);
} else if (fmt[1] == 'V') {
const unsigned char *p = va_arg(ap, const unsigned char *);
int n = va_arg(ap, int);
len += out->printer(out, quote, 1);
len += b64enc(out, p, n);
len += out->printer(out, quote, 1);
} else if (fmt[1] == 'Q' ||
(fmt[1] == '.' && fmt[2] == '*' && fmt[3] == 'Q')) {
size_t l = 0;
const char *p;
if (fmt[1] == '.') {
l = (size_t) va_arg(ap, int);
skip += 2;
}
p = va_arg(ap, char *);
if (p == NULL) {
len += out->printer(out, null, 4);
} else {
if (fmt[1] == 'Q') {
l = strlen(p);
}
len += out->printer(out, quote, 1);
len += json_encode_string(out, p, l);
len += out->printer(out, quote, 1);
}
} else {
/*
* we delegate printing to the system printf.
* The goal here is to delegate all modifiers parsing to the system
* printf, as you can see below we still have to parse the format
* types.
*
* Currently, %s with strings longer than 20 chars will require
* double-buffering (an auxiliary buffer will be allocated from heap).
* TODO(dfrank): reimplement %s and %.*s in order to avoid that.
*/
const char *end_of_format_specifier = "sdfFgGlhuI.*-0123456789";
size_t n = strspn(fmt + 1, end_of_format_specifier);
char *pbuf = buf;
size_t need_len;
char fmt2[20];
va_list sub_ap;
strncpy(fmt2, fmt, n + 1 > sizeof(fmt2) ? sizeof(fmt2) : n + 1);
fmt2[n + 1] = '\0';
va_copy(sub_ap, ap);
need_len =
vsnprintf(buf, sizeof(buf), fmt2, sub_ap) + 1 /* null-term */;
/*
* TODO(lsm): Fix windows & eCos code path here. Their vsnprintf
* implementation returns -1 on overflow rather needed size.
*/
if (need_len > sizeof(buf)) {
/*
* resulting string doesn't fit into a stack-allocated buffer `buf`,
* so we need to allocate a new buffer from heap and use it
*/
pbuf = (char *) malloc(need_len);
va_copy(sub_ap, ap);
vsnprintf(pbuf, need_len, fmt2, sub_ap);
}
/*
* however we need to parse the type ourselves in order to advance
* the va_list by the correct amount; there is no portable way to
* inherit the advancement made by vprintf.
* 32-bit (linux or windows) passes va_list by value.
*/
if ((n + 1 == strlen("%" PRId64) && strcmp(fmt2, "%" PRId64) == 0) ||
(n + 1 == strlen("%" PRIu64) && strcmp(fmt2, "%" PRIu64) == 0)) {
(void) va_arg(ap, int64_t);
skip += strlen(PRIu64) - 1;
} else if (strcmp(fmt2, "%.*s") == 0) {
(void) va_arg(ap, int);
(void) va_arg(ap, char *);
} else {
switch (fmt2[n]) {
case 'u':
case 'd':
(void) va_arg(ap, int);
break;
case 'g':
case 'f':
(void) va_arg(ap, double);
break;
case 'p':
(void) va_arg(ap, void *);
break;
default:
/* many types are promoted to int */
(void) va_arg(ap, int);
}
}
len += out->printer(out, pbuf, strlen(pbuf));
skip = n + 1;
/* If buffer was allocated from heap, free it */
if (pbuf != buf) {
free(pbuf);
pbuf = NULL;
}
}
fmt += skip;
} else if (*fmt == '_' || is_alpha(*fmt)) {
len += out->printer(out, quote, 1);
while (*fmt == '_' || is_alpha(*fmt) || is_digit(*fmt)) {
len += out->printer(out, fmt, 1);
fmt++;
}
len += out->printer(out, quote, 1);
} else {
fmt++;
}
}
va_end(ap);
return len;
}
int json_printf(struct json_out *out, const char *fmt, ...) WEAK;
int json_printf(struct json_out *out, const char *fmt, ...) {
int n;
va_list ap;
va_start(ap, fmt);
n = json_vprintf(out, fmt, ap);
va_end(ap);
return n;
}
int json_printf_array(struct json_out *out, va_list *ap) WEAK;
int json_printf_array(struct json_out *out, va_list *ap) {
int len = 0;
char *arr = va_arg(*ap, char *);
size_t i, arr_size = va_arg(*ap, size_t);
size_t elem_size = va_arg(*ap, size_t);
const char *fmt = va_arg(*ap, char *);
len += json_printf(out, "[", 1);
for (i = 0; arr != NULL && i < arr_size / elem_size; i++) {
union {
int64_t i;
double d;
} val;
memcpy(&val, arr + i * elem_size,
elem_size > sizeof(val) ? sizeof(val) : elem_size);
if (i > 0) len += json_printf(out, ", ");
if (strchr(fmt, 'f') != NULL) {
len += json_printf(out, fmt, val.d);
} else {
len += json_printf(out, fmt, val.i);
}
}
len += json_printf(out, "]", 1);
return len;
}
#ifdef _WIN32
int cs_win_vsnprintf(char *str, size_t size, const char *format, va_list ap) WEAK;
int cs_win_vsnprintf(char *str, size_t size, const char *format, va_list ap) {
int res = _vsnprintf(str, size, format, ap);
va_end(ap);
if (res >= size) {
str[size - 1] = '\0';
}
return res;
}
int cs_win_snprintf(char *str, size_t size, const char *format, ...) WEAK;
int cs_win_snprintf(char *str, size_t size, const char *format, ...) {
int res;
va_list ap;
va_start(ap, format);
res = vsnprintf(str, size, format, ap);
va_end(ap);
return res;
}
#endif /* _WIN32 */
int json_walk(const char *json_string, int json_string_length,
json_walk_callback_t callback, void *callback_data) WEAK;
int json_walk(const char *json_string, int json_string_length,
json_walk_callback_t callback, void *callback_data) {
struct frozen frozen;
memset(&frozen, 0, sizeof(frozen));
frozen.end = json_string + json_string_length;
frozen.cur = json_string;
frozen.callback_data = callback_data;
frozen.callback = callback;
TRY(doit(&frozen));
return frozen.cur - json_string;
}
struct scan_array_info {
char path[JSON_MAX_PATH_LEN];
struct json_token *token;
};
static void json_scanf_array_elem_cb(void *callback_data, const char *name,
size_t name_len, const char *path,
const struct json_token *token) {
struct scan_array_info *info = (struct scan_array_info *) callback_data;
(void) name;
(void) name_len;
if (strcmp(path, info->path) == 0) {
*info->token = *token;
}
}
int json_scanf_array_elem(const char *s, int len, const char *path, int idx,
struct json_token *token) WEAK;
int json_scanf_array_elem(const char *s, int len, const char *path, int idx,
struct json_token *token) {
struct scan_array_info info;
info.token = token;
memset(token, 0, sizeof(*token));
snprintf(info.path, sizeof(info.path), "%s[%d]", path, idx);
json_walk(s, len, json_scanf_array_elem_cb, &info);
return token->len;
}
struct json_scanf_info {
int num_conversions;
char *path;
const char *fmt;
void *target;
void *user_data;
int type;
};
int json_unescape(const char *src, int slen, char *dst, int dlen) WEAK;
int json_unescape(const char *src, int slen, char *dst, int dlen) {
char *send = (char *) src + slen, *dend = dst + dlen, *orig_dst = dst, *p;
const char *esc1 = "\"\\/bfnrt", *esc2 = "\"\\/\b\f\n\r\t";
while (src < send) {
if (*src == '\\') {
if (++src >= send) return JSON_STRING_INCOMPLETE;
if (*src == 'u') {
/* TODO(lsm): \uXXXX escapes drag utf8 lib... Do it at some stage */
return JSON_STRING_INVALID;
} else if ((p = (char *) strchr(esc1, *src)) != NULL) {
if (dst < dend) *dst = esc2[p - esc1];
} else {
return JSON_STRING_INVALID;
}
} else {
if (dst < dend) *dst = *src;
}
dst++;
src++;
}
return dst - orig_dst;
}
static void json_scanf_cb(void *callback_data, const char *name,
size_t name_len, const char *path,
const struct json_token *token) {
struct json_scanf_info *info = (struct json_scanf_info *) callback_data;
(void) name;
(void) name_len;
if (strcmp(path, info->path) != 0) {
/* It's not the path we're looking for, so, just ignore this callback */
return;
}
if (token->ptr == NULL) {
/*
* We're not interested here in the events for which we have no value;
* namely, JSON_TYPE_OBJECT_START and JSON_TYPE_ARRAY_START
*/
return;
}
switch (info->type) {
case 'B':
info->num_conversions++;
*(int *) info->target = (token->type == JSON_TYPE_TRUE ? 1 : 0);
break;
case 'M': {
union {
void *p;
json_scanner_t f;
} u = {info->target};
info->num_conversions++;
u.f(token->ptr, token->len, info->user_data);
break;
}
case 'Q': {
char **dst = (char **) info->target;
int unescaped_len = json_unescape(token->ptr, token->len, NULL, 0);
if (unescaped_len >= 0 &&
(*dst = (char *) malloc(unescaped_len + 1)) != NULL) {
info->num_conversions++;
json_unescape(token->ptr, token->len, *dst, unescaped_len);
(*dst)[unescaped_len] = '\0';
}
break;
}
case 'H': {
char **dst = (char **) info->user_data;
int i, len = token->len / 2;
*(int *) info->target = len;
if ((*dst = (char *) malloc(len + 1)) != NULL) {
for (i = 0; i < len; i++) {
(*dst)[i] = hexdec(token->ptr + 2 * i);
}
(*dst)[len] = '\0';
info->num_conversions++;
}
break;
}
case 'V': {
char **dst = (char **) info->target;
int len = token->len * 4 / 3 + 2;
if ((*dst = (char *) malloc(len + 1)) != NULL) {
int n = b64dec(token->ptr, token->len, *dst);
(*dst)[n] = '\0';
*(int *) info->user_data = n;
info->num_conversions++;
}
break;
}
case 'T':
info->num_conversions++;
*(struct json_token *) info->target = *token;
break;
default:
info->num_conversions += sscanf(token->ptr, info->fmt, info->target);
break;
}
}
int json_vscanf(const char *s, int len, const char *fmt, va_list ap) WEAK;
int json_vscanf(const char *s, int len, const char *fmt, va_list ap) {
char path[JSON_MAX_PATH_LEN] = "", fmtbuf[20];
int i = 0;
char *p = NULL;
struct json_scanf_info info = {0, path, fmtbuf, NULL, NULL, 0};
while (fmt[i] != '\0') {
if (fmt[i] == '{') {
strcat(path, ".");
i++;
} else if (fmt[i] == '}') {
if ((p = strrchr(path, '.')) != NULL) *p = '\0';
i++;
} else if (fmt[i] == '%') {
info.target = va_arg(ap, void *);
info.type = fmt[i + 1];
switch (fmt[i + 1]) {
case 'M':
case 'V':
case 'H':
info.user_data = va_arg(ap, void *);
/* FALLTHROUGH */
case 'B':
case 'Q':
case 'T':
i += 2;
break;
default: {
const char *delims = ", \t\r\n]}";
int conv_len = strcspn(fmt + i + 1, delims) + 1;
snprintf(fmtbuf, sizeof(fmtbuf), "%.*s", conv_len, fmt + i);
i += conv_len;
i += strspn(fmt + i, delims);
break;
}
}
json_walk(s, len, json_scanf_cb, &info);
} else if (is_alpha(fmt[i]) || get_utf8_char_len(fmt[i]) > 1) {
const char *delims = ": \r\n\t";
int key_len = strcspn(&fmt[i], delims);
if ((p = strrchr(path, '.')) != NULL) p[1] = '\0';
sprintf(path + strlen(path), "%.*s", key_len, &fmt[i]);
i += key_len + strspn(fmt + i + key_len, delims);
} else {
i++;
}
}
return info.num_conversions;
}
int json_scanf(const char *str, int len, const char *fmt, ...) WEAK;
int json_scanf(const char *str, int len, const char *fmt, ...) {
int result;
va_list ap;
va_start(ap, fmt);
result = json_vscanf(str, len, fmt, ap);
va_end(ap);
return result;
}