Add support to directly send binary data in http reply

[achillis2016]

Hello, thanks so much for your hard work on this project mongoose, I love it .

Sometimes I need to directly send binary data in http reply, but I found it hard.
I know the data length before send ,so I don't want to use mg_http_write_chunk。
I have to build http response header by myself，but function mg_http_status_code_str is not exposed.

What I want is a function as below:

void mg_http_reply_binary(struct mg_connection *c, int code,const char *headers,
	const char *buf, size_t len) {
	mg_printf(c, "HTTP/1.1 %d %s\r\n%sContent-Length: %d\r\n\r\n", code,
		mg_http_status_code_str(code), headers == NULL ? "" : headers, len);

	mg_send(c, buf, len);
	c->is_resp = 0;
}

then I can use this function to directly send binary data as response :

void handler(struct mg_connection *c, int ev, void *ev_data) 
{
	if (ev != MG_EV_HTTP_MSG) return ;
	
	struct mg_http_message *hm = (struct mg_http_message *)ev_data;
	
	if (mg_match(hm->uri, mg_str("/bin"), NULL)) 
	{
		unsigned char data[8] = {'A','B', 0, 'C', 'D'};  //notice that there is a \x00 in data
		mg_http_reply_binary(c, 200, "Content-Type: application/octet-stream\r\n", (const char*)data, 5);
		return;
	}
	else
	{
		mg_http_reply(c,404,"","no matched uri");
	}
}

Otherwise, the function mg_http_status_code_str is very helpful, I suggest that this function can be exposed, just add a declare in mongoose.h and remove the word "static" before the function body.

[scaprile]

This is not a Mongoose issue. This is you requesting something. Please don't add issues requesting features, there's a feature request section
Converted