Initial revision

[helm.git] / helm / interface / xsltProcessor.ml

diff --git a/helm/interface/xsltProcessor.ml b/helm/interface/xsltProcessor.ml
new file mode 100644 (file)
index 0000000..c82a8f5
--- /dev/null
+++ b/helm/interface/xsltProcessor.ml
@@ -0,0 +1,64 @@
+exception XsltProcessorCouldNotSend;;
+exception XsltProcessorCouldNotReceive;;
+
+let portserver = 12345;;
+let portclient = 12346;;
+let time_to_wait = 10;;
+
+let rec process uri usecache mode =
+ let module U = Unix in
+  let uri = UriManager.string_of_uri uri in
+  let pid = string_of_int (U.getpid ())
+  and filename' =
+   let uri' = Str.replace_first (Str.regexp ".*:") "" uri in
+    Str.global_replace (Str.regexp "/") "_"
+     (Str.global_replace (Str.regexp "_") "__" uri')
+  in let tmpfile = "/tmp/helm_" ^ filename' ^ "_" ^ pid in
+   (* test if the cache can be used *)
+   let tmp_file_exists = Sys.file_exists tmpfile in
+    if usecache && tmp_file_exists then
+     tmpfile
+    else
+     let url = Configuration.getter_url ^ uri in
+      (* purge the cache if asked to *)
+      if not usecache && tmp_file_exists then
+        Sys.remove tmpfile ;
+      let string_to_send = mode ^ " " ^ url ^ " " ^ tmpfile in
+      (* next function is for looping in case the server is not responding *)
+      let rec contact_server () =
+       let socketclient = U.socket U.PF_INET U.SOCK_DGRAM 0
+       and socketserver = U.socket U.PF_INET U.SOCK_DGRAM 0 in
+        let bounded = ref false in
+         while not !bounded do
+          try
+           U.bind socketclient (U.ADDR_INET(U.inet_addr_any,portclient)) ;
+           bounded := true
+          with _ ->
+           print_endline "Port unavailable. Retrying..." ; flush stdout ;
+           U.sleep 5  (* wait hoping the inetaddr is released *)
+         done ;
+         let n =
+          U.sendto socketserver string_to_send 0 (String.length string_to_send)
+           [] (U.ADDR_INET(U.inet_addr_any,portserver))
+         in
+          if n = -1 then raise XsltProcessorCouldNotSend ;
+          U.close socketserver ;
+          let process_signal _ = U.close socketclient in
+          Sys.set_signal Sys.sigalrm (Sys.Signal_handle process_signal) ;
+          (* if the server does not respond, repeat the query *)
+          ignore (U.alarm time_to_wait) ;
+          try
+           if U.recv socketclient "" 0 0 [] = -1 then
+            raise XsltProcessorCouldNotReceive ;
+           ignore (U.alarm 0) ; (* stop the bomb *)
+           Sys.set_signal Sys.sigalrm Sys.Signal_default ;
+           U.close socketclient ;
+           tmpfile
+          with
+           U.Unix_error(_,"recv",_) ->
+            print_endline "Xaland server not responding. Retrying..." ;
+            flush stdout;
+            contact_server ()
+        in
+         contact_server ()
+;;