let try_finalise f x finally y =
let res = try f x with e -> finally y; raise e in
finally y;
res
let rec restart_on_EINTR f x =
try f x with Unix.Unix_error (Unix.EINTR, _, _) -> restart_on_EINTR f x
let double_fork_treatment server service (client_descr, _ as client) =
let treat () =
match Unix.fork () with
| 0 ->
if Unix.fork () <> 0 then exit 0;
Unix.close server; service client; exit 0
| k ->
ignore (restart_on_EINTR (Unix.waitpid []) k)
in
try_finalise treat () Unix.close client_descr
let install_tcp_server_socket addr =
let s = Unix.socket Unix.PF_INET Unix.SOCK_STREAM 0 in
try
Unix.bind s addr;
Unix.listen s 10;
s
with e -> Unix.close s; raise e
let tcp_server treat_connection addr =
ignore (Sys.signal Sys.sigpipe Sys.Signal_ignore);
let server_sock = install_tcp_server_socket addr in
while true do
let client = restart_on_EINTR Unix.accept server_sock in
treat_connection server_sock client
done
let server () =
let port = 8080 in
let host = (Unix.gethostbyname (Unix.gethostname())).Unix.h_addr_list.(0) in
let addr = Unix.ADDR_INET (host, port) in
let treat sock (client_sock, client_addr as client) =
let service (s, _) =
let response = "\
HTTP/1.1 200 OK\r\n\
Content-Type: text/html; charset=UTF-8\r\n\r\n\
Goodbye, world!\
\
Goodbye, world!
\r\n"
in
Unix.write s response 0 (String.length response);
in
double_fork_treatment sock service client
in
tcp_server treat addr
let _ =
Unix.handle_unix_error server ()