path: root/0002-Added-Support-for-with-python-and-python.patch

From c8025ac6bd9874663f4445288056702c424db8cb Mon Sep 17 00:00:00 2001
From: Thierry Martinez <martinez@nsup.org>
Date: Tue, 18 Oct 2016 18:38:05 +0200
Subject: [PATCH 2/2] Added: Support for --with-python and --python

The option --with-python is restored in configure to give a default
path/command for the Python interpreter.

The value can be overwritten with the --python option in the command
line.

Py.ml library has been updated to support custom Python interpreters. As
a side effect, the environment variable PYTHONHOME is now dynamically
set if it is not already defined. It should make the Python library work
even on systems where the environment variable has not been properly
set.
---
 bundles/pyml/pyml-current/py.ml        | 94 ++++++++++++++++++++++++++--------
 bundles/pyml/pyml-current/py.mli       | 10 ++--
 bundles/pyml/pyml-current/pyml_stubs.c | 24 +++++++--
 changes.txt                            |  2 +
 configure.ac                           | 10 ++++
 globals/config.ml.in                   |  2 +
 main.ml                                |  2 +
 python/yes_pycocci.ml                  |  2 +-
 8 files changed, 116 insertions(+), 30 deletions(-)

diff --git a/bundles/pyml/pyml-current/py.ml b/bundles/pyml/pyml-current/py.ml
index b0f64ce..50caab2 100644
--- a/bundles/pyml/pyml-current/py.ml
+++ b/bundles/pyml/pyml-current/py.ml
@@ -6,7 +6,8 @@ type compare = Pytypes.compare = LT | LE | EQ | NE | GT | GE
 
 type ucs = UCSNone | UCS2 | UCS4
 
-external load_library: int -> string option -> unit = "py_load_library"
+external load_library: string option -> unit = "py_load_library"
+external unsetenv: string -> unit = "py_unsetenv"
 external finalize_library: unit -> unit = "py_finalize_library"
 external pywrap_closure: string -> (pyobject -> pyobject) -> pyobject
     = "pywrap_closure"
@@ -84,13 +85,13 @@ let extract_version version_line =
 
 let extract_version_major_minor version =
   try
-    let first_dot = String.index version '.' in
-    let second_dot = String.index_from version (succ first_dot) '.' in
-    let major = int_of_string (String.sub version 0 first_dot) in
-    let minor =
-      int_of_string (substring_between version first_dot second_dot) in
-    (major, minor)
-  with Not_found | Failure _ ->
+    if String.length version >= 3 && (String.sub version 1 1 = ".") then
+      let major = int_of_string (String.sub version 0 1) in
+      let minor = int_of_string (String.sub version 2 1) in
+      (major, minor)
+    else
+      raise Exit
+  with Exit | Failure _ ->
     let msg =
       Printf.sprintf
         "Py.extract_version_major: unable to parse the version number '%s'"
@@ -134,6 +135,19 @@ let rec split string ?(from=0) separator =
       let word = String.sub string from (position - from) in
       word :: split string ~from:(succ position) separator
 
+let parent_dir filename =
+  let dirname = Filename.dirname filename in
+  Filename.concat dirname Filename.parent_dir_name
+
+let has_putenv = ref false
+
+let init_pythonhome pythonhome =
+  try
+    ignore (Sys.getenv "PYTHONHOME")
+  with Not_found ->
+    Unix.putenv "PYTHONHOME" pythonhome;
+    has_putenv := true
+
 let find_library_path version_major version_minor =
   let command =
     Printf.sprintf "pkg-config --libs python-%d.%d" version_major
@@ -144,10 +158,16 @@ let find_library_path version_major version_minor =
   with
     None ->
       let library_paths =
-        try
-          [Filename.concat (Filename.dirname (run_command "which python" false))
-             "../lib"]
-        with Failure _ -> [] in
+        match
+          try Some (Sys.getenv "PYTHONHOME")
+          with Not_found -> None
+        with
+          None -> []
+        | Some pythonhome ->
+            let prefix =
+              try String.sub pythonhome 0 (String.index pythonhome ':')
+              with Not_found -> pythonhome in
+            [Filename.concat prefix "lib"] in
       let library_filenames =
         [Printf.sprintf "python%d.%dm" version_major version_minor;
          Printf.sprintf "python%d.%d" version_major version_minor] in
@@ -177,8 +197,20 @@ let find_library_path version_major version_minor =
         | Some library_filename -> library_filename in
       (library_paths, [library_filename])
 
-let initialize_version_value python =
-  let version_line = run_command (Printf.sprintf "%s --version" python) true in
+let initialize_version_value interpreter =
+  begin
+    let python_full_path =
+      if String.contains interpreter '/' then interpreter
+      else
+        let which_python = Printf.sprintf "which \"%s\"" interpreter in
+        run_command which_python false in
+    let pythonhome = parent_dir python_full_path in
+    init_pythonhome pythonhome
+  end;
+  let version_line =
+    let python_version_cmd = Printf.sprintf "\"%s\" --version" interpreter in
+    try run_command python_version_cmd false
+    with Failure _ -> run_command python_version_cmd true in
   let version = extract_version version_line in
   let (version_major, version_minor) = extract_version_major_minor version in
   version_value := version;
@@ -187,7 +219,7 @@ let initialize_version_value python =
 
 let find_library () =
   try
-    load_library !version_major_value None
+    load_library None
   with Failure _ ->
     let (library_paths, library_filenames) =
       find_library_path !version_major_value !version_minor_value in
@@ -206,7 +238,9 @@ let find_library () =
         [] -> failwith "Py.find_library: unable to find the Python library"
       | filename :: others ->
           begin
-            try load_library !version_major_value (Some filename)
+            try
+              init_pythonhome (parent_dir filename);
+              load_library (Some filename)
             with Failure _ -> try_load_library others
           end in
     try_load_library library_filenames
@@ -220,16 +254,38 @@ let initialize_library () =
     | Some s -> set_python_home s
   end
 
-let initialize ?(interpreter = "python") () =
+let get_version = Pywrappers.py_getversion
+
+let initialize ?(interpreter = "python") ?version () =
   if !initialized then
     failwith "Py.initialize: already initialized";
-  initialize_version_value interpreter;
+  begin
+    match version with
+      Some (version_major, version_minor) ->
+        version_major_value := version_major;
+        version_minor_value := version_minor
+    | _ ->
+        initialize_version_value interpreter;
+  end;
   initialize_library ();
+  let version = get_version () in
+  let (version_major, version_minor) = extract_version_major_minor version in
+  if version_major != !version_major_value ||
+    version_minor != !version_minor_value then
+    begin
+      finalize_library ();
+      failwith "Version mismatch"
+    end;
   initialized := true
 
 let finalize () =
   assert_initialized ();
   finalize_library ();
+  if !has_putenv then
+    begin
+      unsetenv "PYTHONHOME";
+      has_putenv := false
+    end;
   initialized := false
 
 let version () =
@@ -335,8 +391,6 @@ let get_path () =
   else
     Pywrappers.Python3.py_getpath ()
 
-let get_version = Pywrappers.py_getversion
-
 let get_platform = Pywrappers.py_getplatform
 
 let get_copyright = Pywrappers.py_getcopyright
diff --git a/bundles/pyml/pyml-current/py.mli b/bundles/pyml/pyml-current/py.mli
index 8553cf4..f8db91e 100644
--- a/bundles/pyml/pyml-current/py.mli
+++ b/bundles/pyml/pyml-current/py.mli
@@ -2,12 +2,14 @@
 
 (** Call [initialize ()] first. *)
 
-val initialize: ?interpreter:string -> unit -> unit
-(** [initialize ~interpreter ()] finds and loads the Python library.
+val initialize: ?interpreter:string -> ?version:(int * int) -> unit -> unit
+(** [initialize ~interpreter ~version ()] finds and loads the Python library.
     This function should be called before any other functions, except
     if explicitely mentioned.
-    The version of Python is determined by the output of the shell command
-    [python --version].
+    [version] should be a pair specifying the major and the minor version
+    number.
+    If no version number is given, the version of Python is determined by the
+    output of the shell command [python --version].
     If an [interpreter] executable name is given, this executable is
     used in place of [python] in the previous command line.
     The library is searched by
diff --git a/bundles/pyml/pyml-current/pyml_stubs.c b/bundles/pyml/pyml-current/pyml_stubs.c
index c8d33af..5732026 100644
--- a/bundles/pyml/pyml-current/pyml_stubs.c
+++ b/bundles/pyml/pyml-current/pyml_stubs.c
@@ -12,6 +12,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <errno.h>
 
 /* The following definitions are extracted and simplified from
 #include <Python.h>
@@ -458,10 +459,9 @@ pywrap_closure(value docstring, value closure)
 }
 
 CAMLprim value
-py_load_library(value version_major_ocaml, value filename_ocaml)
+py_load_library(value filename_ocaml)
 {
-    CAMLparam2(version_major_ocaml, filename_ocaml);
-    version_major = Int_val(version_major_ocaml);
+    CAMLparam1(filename_ocaml);
     if (Is_block(filename_ocaml)) {
         char *filename = String_val(Field(filename_ocaml, 0));
         library = dlopen(filename, RTLD_LAZY);
@@ -472,10 +472,13 @@ py_load_library(value version_major_ocaml, value filename_ocaml)
     else {
         library = RTLD_DEFAULT;
     }
-    Python_PyCFunction_NewEx = dlsym(library, "PyCFunction_NewEx");
-    if (!Python_PyCFunction_NewEx) {
+    Python_Py_GetVersion = dlsym(library, "Py_GetVersion");
+    if (!Python_Py_GetVersion) {
         failwith("No Python symbol");
     }
+    const char *version = Python_Py_GetVersion();
+    version_major = version[0] - '0';
+    Python_PyCFunction_NewEx = resolve("PyCFunction_NewEx");
     Python_PyCapsule_New = resolve("PyCapsule_New");
     Python_PyCapsule_GetPointer = resolve("PyCapsule_GetPointer");
     Python_PyObject_CallFunctionObjArgs =
@@ -524,6 +527,17 @@ py_finalize_library(value unit)
 }
 
 CAMLprim value
+py_unsetenv(value name_ocaml)
+{
+    CAMLparam1(name_ocaml);
+    char *name = String_val(name_ocaml);
+    if (unsetenv(name) == -1) {
+        failwith(strerror(errno));
+    }
+    CAMLreturn(Val_unit);
+}
+
+CAMLprim value
 py_get_UCS(value unit)
 {
     CAMLparam1(unit);
diff --git a/changes.txt b/changes.txt
index 4a48965..552bb3f 100644
--- a/changes.txt
+++ b/changes.txt
@@ -16,6 +16,8 @@
 - New scripting languages
 - more than one SP on the command line
 - interpret #if, as is done for #ifdef
+- restored support for with-python in configure and support for --python option
+  in the command line to use a specific python interpreter
 
 ** Bugfix:
 - Add more information in documentation, man pages and wiki
diff --git a/configure.ac b/configure.ac
index 8402b59..fa51ca5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -276,6 +276,16 @@ dnl  variables:
 dnl    with_python: whether to enable the python feature (and what version)
 AC_ARG_ENABLE([python], [AS_HELP_STRING([--enable-python], [enable python scripting (yes/no) (default: auto)])])
 
+AC_ARG_WITH([python], [AS_HELP_STRING([--with-python], [which python interpreter to use (default: python)])])
+
+AS_IF([test -n "$with_python"],
+[dnl
+  AC_SUBST([PYTHON], ["$with_python"])
+],
+[dnl
+  AC_SUBST([PYTHON], ["python"])
+])
+
 AS_IF([test "x$enable_python" != xno],
 [dnl
   AC_CHECK_COCCI_EXTPKG([pyml])  dnl  will set $enable_pyml to 'yes', 'no', or 'local'
diff --git a/globals/config.ml.in b/globals/config.ml.in
index 978fa77..02b7ef1 100644
--- a/globals/config.ml.in
+++ b/globals/config.ml.in
@@ -12,3 +12,5 @@ let get_temp_dir_name = @GET_TEMP_DIR_NAME_EXPR@
 
 let configure_flags = "@CONFIGURE_FLAGS@"
 let ocaml_version = "@OCAMLVERSION@"
+
+let python_interpreter = ref "@PYTHON@"
diff --git a/main.ml b/main.ml
index 66aaff4..2444d39 100644
--- a/main.ml
+++ b/main.ml
@@ -353,6 +353,8 @@ let short_options = [
    "    \"\" for a file in the current directory");
   "--kbuild-info", Arg.Set_string kbuild_info,
   "    <file> improve -dir by grouping related c files";
+  "--python", Arg.Set_string Config.python_interpreter,
+  "    Sets the path to the python interpreter";
   "--pyoutput", Arg.Set_string Flag.pyoutput,
   "    Sets output routine: Standard values: <coccilib.output.Gtk|coccilib.output.Console>";
   "--parse-handler",
diff --git a/python/yes_pycocci.ml b/python/yes_pycocci.ml
index 920d22f..55ac501 100644
--- a/python/yes_pycocci.ml
+++ b/python/yes_pycocci.ml
@@ -172,7 +172,7 @@ let pycocci_init () =
   initialised := true;
   let _ = if not (Py.is_initialized ()) then
   	(if !Flag.show_misc then Common.pr2 "Initializing python\n%!";
-	Py.initialize ()) in
+	Py.initialize ~interpreter:!Config.python_interpreter ()) in
 
   (* set argv *)
   let argv0 = Sys.executable_name in
-- 
2.10.1