[sqlite] fix daemon logic in non-forking integrations

Summary:
In integrations where the capturing process isn't forked off the main Infer process, but launched, eg, via a script pretending to be a compiler, the reference indicating whether the server is running will always be false, and thus such integrations will never try to connect to the write daemon.

Fix this by
- making `sqlite-write-daemon` authoritative wrt connecting to the daemon.
- launching the daemon earlier in the setup process.

Reviewed By: jberdine

Differential Revision: D17204002

fbshipit-source-id: 23d452fac

infer/src/base/DBWriter.ml

@@ -293,21 +293,13 @@ module Server = struct
         send Command.Handshake
 end
 
-let server_running = ref false
+let use_daemon = Config.(sqlite_write_daemon && (not (buck || genrule_mode)) && jobs > 1)
 
-let perform cmd = if !server_running then Server.send cmd else Command.execute cmd
+let perform cmd = if use_daemon then Server.send cmd else Command.execute cmd
 
-let start () =
-  if not !server_running then (
-    Server.start () ;
-    server_running := true )
-
-
-let stop () =
-  if !server_running then (
-    Server.send Command.Terminate ;
-    server_running := false )
+let start () = Server.start ()
 
+let stop () = Server.send Command.Terminate
 
 let replace_attributes ~pname_str ~pname ~akind ~source_file ~attributes ~proc_desc ~callees =
   Command.ReplaceAttributes {pname_str; pname; akind; source_file; attributes; proc_desc; callees}

infer/src/base/DBWriter.mli

@@ -8,6 +8,9 @@
 
 open! IStd
 
+val use_daemon : bool
+(** indicates that there should be a daemon running *)
+
 val replace_attributes :
      pname_str:string
   -> pname:Sqlite3.Data.t

infer/src/infer.ml

@@ -26,6 +26,14 @@ let run driver_mode =
 let run driver_mode = ScubaLogging.execute_with_time_logging "run" (fun () -> run driver_mode)
 
 let setup () =
+  let db_start =
+    let already_started = ref false in
+    fun () ->
+      if (not !already_started) && CLOpt.is_originator && DBWriter.use_daemon then (
+        DBWriter.start () ;
+        Epilogues.register ~f:DBWriter.stop ~description:"Stop Sqlite write daemon" ;
+        already_started := true )
+  in
   ( match Config.command with
   | Analyze ->
       ResultsDir.assert_results_dir "have you run capture before?"
@@ -49,18 +57,16 @@ let setup () =
       if
         CLOpt.is_originator && (not Config.continue_capture)
         && not Driver.(equal_mode driver_mode Analyze)
-      then SourceFiles.mark_all_stale ()
+      then ( db_start () ; SourceFiles.mark_all_stale () )
   | Explore ->
       ResultsDir.assert_results_dir "please run an infer analysis first"
   | Events ->
       ResultsDir.assert_results_dir "have you run infer before?" ) ;
+  db_start () ;
   if CLOpt.is_originator then (
     RunState.add_run_to_sequence () ;
     RunState.store () ;
-    if Config.memcached then Memcached.start () ;
-    if Config.(sqlite_write_daemon && (not (buck || genrule_mode)) && jobs > 1) then (
-      DBWriter.start () ;
-      Epilogues.register ~f:DBWriter.stop ~description:"Stop Sqlite write daemon" ) ) ;
+    if Config.memcached then Memcached.start () ) ;
   ()