Add config option for FCP_CLANG_INCLUDE_TO_REPLACE

Summary:
Add config (and thereby both command line and .inferconfig file)
option for FCP_CLANG_INCLUDE_TO_REPLACE.

Reviewed By: jvillard

Differential Revision: D3455993

fbshipit-source-id: dc3dfe4

infer/src/backend/config.ml

@@ -484,6 +484,12 @@ and calls_csv =
   CLOpt.mk_option ~deprecated:["calls"] ~long:"calls-csv" ~f:create_outfile
     ~meta:"calls.csv" "Write individual calls in csv format to calls.csv"
 
+and clang_include_to_override =
+  CLOpt.mk_string_opt ~long:"clang-include-to-override" ~meta:"dir"
+    "Use this option in the uncommon case where the normal compilation process overrides the \
+     location of internal compiler headers. This option should specify the path to those headers \
+     so that infer can use its own clang internal headers instead."
+
 (* Default is objc, since it's the default for clang (at least in Mac OS) *)
 and clang_lang =
   CLOpt.mk_symbol ~long:"clang-lang" ~short:"x" ~default:OBJC
@@ -1190,6 +1196,7 @@ and calls_csv = !calls_csv
 and checkers = !checkers
 (** should the checkers be run? *)
 and checkers_enabled = not !eradicate
+and clang_include_to_override = !clang_include_to_override
 and clang_lang = !clang_lang
 and cluster_cmdline = !cluster
 and code_query = !code_query

infer/src/backend/config.mli

@@ -134,6 +134,7 @@ val bugs_xml : outfile option
 val calls_csv : outfile option
 val checkers : bool
 val checkers_enabled : bool
+val clang_include_to_override : string option
 val clang_lang : clang_lang
 val cluster_cmdline : string option
 val code_query : string option

infer/src/backend/infer.ml

@@ -0,0 +1,83 @@
+(*
+ * Copyright (c) 2016 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *)
+
+open! Utils
+
+(** Top-level driver that orchestrates build system integration, frontends, and backend *)
+
+let set_env_for_clang_wrapper () =
+  (match Config.clang_include_to_override with
+   | Some dir -> Unix.putenv "FCP_CLANG_INCLUDE_TO_REPLACE" dir
+   | None -> ()
+  );
+  if Config.cxx_experimental then
+    Unix.putenv "FCP_INFER_CXX_MODELS" "1" ;
+  if Config.debug_mode || Config.frontend_stats then
+    Unix.putenv "FCP_DEBUG_MODE" "1" ;
+  if not Config.failures_allowed then
+    Unix.putenv "FCP_REPORT_FRONTEND_FAILURE" "1" ;
+  if Config.llvm then
+    Unix.putenv "LLVM_MODE" "1"
+
+let () =
+  set_env_for_clang_wrapper () ;
+  let ( / ) = Filename.concat in
+  (* The infer executable in the bin directory is a symbolic link to the real binary in the lib
+     directory, so that the python script in the lib directory can be found relative to it. *)
+  let real_exe =
+    match Unix.readlink Sys.executable_name with
+    | link when Filename.is_relative link ->
+        (* Sys.executable_name is a relative symbolic link *)
+        (Filename.dirname Sys.executable_name) / link
+    | link ->
+        (* Sys.executable_name is an absolute symbolic link *)
+        link
+    | exception Unix.Unix_error(Unix.EINVAL, _, _) ->
+        (* Sys.executable_name is not a symbolic link *)
+        Sys.executable_name
+  in
+  let infer_py = (Filename.dirname real_exe) / "python" / "infer.py" in
+  let build_cmd = IList.rev Config.rest in
+  let buck = match build_cmd with "buck" :: _ -> true | _ -> false in
+  let args_py =
+    Array.of_list (
+      infer_py ::
+      (match Config.analyzer with None -> [] | Some a ->
+        ["--analyzer"; Utils.string_of_analyzer a]) @
+      (match Config.blacklist with
+       | Some s when buck -> ["--blacklist-regex"; s]
+       | _ -> []) @
+      (if not Config.create_harness then [] else
+         ["--android-harness"]) @
+      (if not Config.buck then [] else
+         ["--buck"]) @
+      (if not Config.debug_mode then [] else
+         ["--debug"]) @
+      (if not Config.debug_exceptions then [] else
+         ["--debug-exceptions"]) @
+      (if Config.filtering then [] else
+         ["--no-filtering"]) @
+      (if not Config.flavors || not buck then [] else
+         ["--use-flavors"]) @
+      (match Config.infer_cache with None -> [] | Some s ->
+        ["--infer_cache"; s]) @
+      "--multicore" :: (string_of_int Config.multicore) ::
+      "--out" :: Config.results_dir ::
+      (match Config.project_root with None -> [] | Some pr ->
+        ["--project_root"; pr]) @
+      (if Config.rest = [] then [] else
+         ("--" :: build_cmd))
+    ) in
+  let pid = Unix.create_process args_py.(0) args_py Unix.stdin Unix.stdout Unix.stderr in
+  let _, status = Unix.waitpid [] pid in
+  if status <> Unix.WEXITED 0 then (
+    prerr_endline ("Failed to execute: " ^ (String.concat " " (Array.to_list args_py))) ;
+    exit 1
+  );
+  ()