I'm making a WebServer using STM32F405, the ethernet chip is W5500 from Wiznet.
Wiznet offers an HTTP WebServer demo. However, they use an sd card for loading web content.
I found that Arduino WebServer can load web content without using SD card, it just needs to add some Arduino code inside the sketch.
So the question is how my device load web content without an SD card.
I'm using IAR btw.
Although your question is a bit low on details, I am guessing you want to serve pages from inside your C code without accessing a file system.
I suggest you have a look at Bitty HTTP (shameless plug). I think it's close to what you are looking for. It serves the pages directly from C code (no file system), can work with non standard sockets, and does not require threads (no operating system needed).
I looked at the W5500 and is doesn't seam to use Berkeley sockets (although you maybe able to add this) so you will need to have something that can work without them. Unfortunately you would need to write the socket to W5500 SPI commands part to make it work.
You can also look at other embedded web servers. libmicrohttpd (which is an embedded web server it's self) has a fair list of other embedded web servers. I don't think you will find anything on there that will fit your needs but it's worth a try.