Function parse_string

outofcore/src/cJSON.cpp:152–201

/* Parse the input text into an unescaped cstring, and populate item. */
static const unsigned char firstByteMark[7] = { 0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC };
static const char *parse_string(cJSON *item,const char *str)
{
	const char *ptr=str+1; char *ptr2; char *out; int len=0; unsigned uc;
	if (*str!='\"') {ep=str;return nullptr;}	/* not a string! */
	
	while (*ptr!='\"' && *ptr && ++len) if (*ptr++ == '\\') ptr++;	/* Skip escaped quotes. */
	
	out=static_cast<char*> (cJSON_malloc(len+1));	/* This is how long we need for the string, roughly. */
	if (!out) return nullptr;
	
	ptr=str+1;ptr2=out;
	while (*ptr!='\"' && *ptr)
	{
		if (*ptr!='\\') *ptr2++=*ptr++;
		else
		{
			ptr++;
			switch (*ptr)
			{
				case 'b': *ptr2++='\b';	break;
				case 'f': *ptr2++='\f';	break;
				case 'n': *ptr2++='\n';	break;
				case 'r': *ptr2++='\r';	break;
				case 't': *ptr2++='\t';	break;
				case 'u':	 /* transcode utf16 to utf8. DOES NOT SUPPORT SURROGATE PAIRS CORRECTLY. */
					sscanf(ptr+1,"%4x",&uc);	/* get the unicode char. */
					len=3;if (uc<0x80) len=1;else if (uc<0x800) len=2;ptr2+=len;
					
					switch (len) {
						case 3: *--ptr2 = static_cast<char>(( (uc) | 0x80) & 0xBF );
              uc >>= 6;
              PCL_FALLTHROUGH
						case 2: *--ptr2 = static_cast<char>(( (uc) | 0x80) & 0xBF );
              uc >>= 6;
              PCL_FALLTHROUGH
						case 1: *--ptr2 = static_cast<char>( (uc) | firstByteMark[len] );
					}
					ptr2+=len;ptr+=4;
					break;
				default:  *ptr2++=*ptr; break;
			}
			ptr++;
		}
	}
	*ptr2=0;
	if (*ptr=='\"') ptr++;
	item->valuestring=out;
	item->type=cJSON_String;
	return ptr;
}

/* Render the cstring provided to an escaped version that can be printed. */
static char *print_string_ptr(const char *str)