%% httpd.erl - microhttpd 
-module(httpd). 
-author("ninhenry@gmail.com"). 
 
-export([start/0,start/1,start/2,process/2]). 
-import(regexp,[split/2]). 
 
-define(defport,8888). 
-define(docroot,"public"). 
 
start() -> start(?defport,?docroot). 
start(port) -> start(port,?docroot).  
start(port,docroot) -> 
 case gen_tcp:listen(port, [binary,{packet, 0},{active, false}]) of 
  {ok, lsock} -> server_loop(lsock,docroot); 
   {error, reason}  -> exit({port,reason}) 
 end. 
 
%% main server loop - wait for next connection, spawn child to process it 
server_loop(lsock,docroot) -> 
 case gen_tcp:accept(lsock) of 
  {ok, sock} -> 
   spawn(?module,process,[sock,docroot]), 
   server_loop(lsock,docroot); 
  {error, reason} -> 
   exit({accept,reason}) 
 end. 
 
%% process current connection 
process(sock,docroot) -> 
 req = do_recv(sock), 
 {ok,[cmd|[name|[vers|_]]]} = split(req,"[ \r\n]"), 
 filename = docroot    name, 
 logreq = cmd    " "    name    " "    vers, 
 resp = case file:read_file(filename) of 
  {ok, data} -> 
   io:format("~p ~p ok~n",[logreq,filename]), 
   data; 
  {error, reason} -> 
   io:format("~p ~p failed ~p~n",[logreq,filename,reason]), 
   error_response(logreq,file:format_error(reason)) 
  end,  
 do_send(sock,resp), 
 gen_tcp:close(sock). 
 
%% construct html for failure message 
error_response(logreq,reason) -> 
 "\n"    
 "
erlang实现的一个web服务器代码实例-尊龙凯时
\n"    "your request to "    logreq    
 " failed due to: "    reason    "\n\n". 
 
%% send a line of text to the socket 
do_send(sock,msg) -> 
 case gen_tcp:send(sock, msg) of 
  ok -> ok; 
   {error, reason} -> exit(reason) 
 end. 
 
%% receive data from the socket 
do_recv(sock) -> 
 case gen_tcp:recv(sock, 0) of 
  {ok, bin} -> binary_to_list(bin); 
   {error, closed} -> exit(closed); 
   {error, reason} -> exit(reason) 
 end