Lab supervision

1
Lab supervision

• Lab responsible Phu Phung (phu.phung_at_chalmers.se)
  
• Monday, 10-12am, Room 3507
• Thursday, 10-12am, Room 3354
• Friday, 10-12am, Room 3507
• No other place or email communication
• Description of labs from course homepage
• http//www.cs.chalmers.se/Cs/Grundutb/Kurser/sysc/
  

2
Lab 2- Web server

• The task
• Students work in pairs (highly recommend)
• To write a simple web-server using C following
  HTTP protocol
• To be familiar to multi-process programming
• To process configuration files, to write on log
  files...

3
TCP socket
4
HTTP protocol - RFC 1945

• Request
• GET /phung/index.html HTTP/1.0
• User-agent Mozilla/4.0
• ...
• Response
• HTTP/1.0 200 OK
• Date Thu, 06 Aug 1998 120015 GMT
• Server Apache/1.3.0 (Unix)
• Last-Modified Mon, 22 Jun 1998
• Content-Length 6821
• Content-Type text/html
• data data data data data ...

5

• Multi-process processing

6

• Multi-process server

7
Some hints

• Byte ordering
• Should convert to/from Network by order when
  sending/receiving
• Functions 16bits htons(...), ntohs(...), 32 bit
  htonl(...), ntohl(...)
• Converting address functions
• inet_ntoa(...) binary to dot decimal address
• , inet_aton(...) dot decimal to binary address

8
Submission

• Well-documented
• Test your program before submitting (using some
  popular web browser)
• Submit a packed file (lab2.tar.gz) to the Fire
  system
• https//fire.cs.chalmers.se8013/cgi/Fire-sysc
• Dead line 2007-03-05 2359
• A rejected program should be re-submitted within
  3 days