why not check the "processed" in parson.c

[tianmaduxing]

static int parse_utf16(const char **unprocessed, char **processed) {
//check the processed
	if (!processed)
	{
		return JSONFailure;
	}

    unsigned int cp, lead, trail;
    int parse_succeeded = 0;
    char *processed_ptr = *processed;
    const char *unprocessed_ptr = *unprocessed;
    unprocessed_ptr++; /* skips u */
    parse_succeeded = parse_utf16_hex(unprocessed_ptr, &cp);
    if (!parse_succeeded) {
        return JSONFailure;
    }
    if (cp < 0x80) {
        processed_ptr[0] = (char)cp; /* 0xxxxxxx */
    } else if (cp < 0x800) {
        processed_ptr[0] = ((cp >> 6) & 0x1F) | 0xC0; /* 110xxxxx */
        processed_ptr[1] = ((cp)      & 0x3F) | 0x80; /* 10xxxxxx */
        processed_ptr += 1;
    } else if (cp < 0xD800 || cp > 0xDFFF) {
        processed_ptr[0] = ((cp >> 12) & 0x0F) | 0xE0; /* 1110xxxx */
        processed_ptr[1] = ((cp >> 6)  & 0x3F) | 0x80; /* 10xxxxxx */
        processed_ptr[2] = ((cp)       & 0x3F) | 0x80; /* 10xxxxxx */
        processed_ptr += 2;
    } else if (cp >= 0xD800 && cp <= 0xDBFF) { /* lead surrogate (0xD800..0xDBFF) */
        lead = cp;
        unprocessed_ptr += 4; /* should always be within the buffer, otherwise previous sscanf would fail */
        if (*unprocessed_ptr++ != '\\' || *unprocessed_ptr++ != 'u') {
            return JSONFailure;
        }
        parse_succeeded = parse_utf16_hex(unprocessed_ptr, &trail);
        if (!parse_succeeded || trail < 0xDC00 || trail > 0xDFFF) { /* valid trail surrogate? (0xDC00..0xDFFF) */
            return JSONFailure;
        }
        cp = ((((lead - 0xD800) & 0x3FF) << 10) | ((trail - 0xDC00) & 0x3FF)) + 0x010000;
        processed_ptr[0] = (((cp >> 18) & 0x07) | 0xF0); /* 11110xxx */
        processed_ptr[1] = (((cp >> 12) & 0x3F) | 0x80); /* 10xxxxxx */
        processed_ptr[2] = (((cp >> 6)  & 0x3F) | 0x80); /* 10xxxxxx */
        processed_ptr[3] = (((cp)       & 0x3F) | 0x80); /* 10xxxxxx */
        processed_ptr += 3;
    } else { /* trail surrogate before lead surrogate */
        return JSONFailure;
    }
    unprocessed_ptr += 3;
    *processed = processed_ptr;
    *unprocessed = unprocessed_ptr;
    return JSONSuccess;
}