06/09: guix: 'guile' executable ignores GUILE_LOAD_PATH during startup.

[guix-commits]

civodul pushed a commit to branch master
in repository guix.

commit d20665ecbfe7278f550a1ed4cd76565013feab59
Author: Ludovic Courtès <ludo@gnu.org>
AuthorDate: Mon Dec 7 15:20:11 2020 +0100

    guix: 'guile' executable ignores GUILE_LOAD_PATH during startup.
    
    When starting the 'guix' command, this ensures Guile modules are
    immediately found instead of being search for in other directories.
    This reduces the number of 'stat' calls during startup when
    GUILE_LOAD_PATH is set to (almost) that of "env -i $(type -P guix)".
    
    * gnu/packages/aux-files/guile-launcher.c (load_path)
    (load_compiled_path): New variables.
    (inner_main): Restore GUILE_LOAD_PATH and GUILE_LOAD_COMPILED_PATH and
    set %load-path and %load-compiled-path accordingly.
    (main): Save GUILE_LOAD_PATH and GUILE_LOAD_COMPILED_PATH and unset them.
---
 gnu/packages/aux-files/guile-launcher.c | 46 +++++++++++++++++++++++++++++++--
 1 file changed, 44 insertions(+), 2 deletions(-)

diff --git a/gnu/packages/aux-files/guile-launcher.c 
b/gnu/packages/aux-files/guile-launcher.c
index 886ede2..1dd5d77 100644
--- a/gnu/packages/aux-files/guile-launcher.c
+++ b/gnu/packages/aux-files/guile-launcher.c
@@ -1,5 +1,5 @@
 /* GNU Guix --- Functional package management for GNU
-   Copyright 1996-1997,2000-2001,2006,2008,2011,2013,2018
+   Copyright 1996-1997,2000-2001,2006,2008,2011,2013,2018,2020
       Free Software Foundation, Inc.
    Copyright (C) 2020 Ludovic Courtès <ludo@gnu.org>
 
@@ -19,14 +19,47 @@
    along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.  */
 
 /* This file implements a variant of the 'guile' executable that does not
-   complain about locale issues.  */
+   complain about locale issues and arranges to reduce startup time by
+   ignoring GUILE_LOAD_PATH and GUILE_LOAD_COMPILED_PATH until it has
+   booted.  */
 
+#include <stdlib.h>
+#include <string.h>
 #include <locale.h>
 #include <libguile.h>
 
+/* Saved values of GUILE_LOAD_PATH and GUILE_LOAD_COMPILED_PATH.  */
+static const char *load_path, *load_compiled_path;
+
 static void
 inner_main (void *unused, int argc, char **argv)
 {
+  if (load_path != NULL)
+    {
+      setenv ("GUILE_LOAD_PATH", load_path, 1);
+      SCM load_path_var =
+       scm_c_public_lookup ("guile", "%load-path");
+      SCM addition =
+       scm_parse_path (scm_from_locale_string (load_path), SCM_EOL);
+      scm_variable_set_x (load_path_var,
+                         scm_append
+                         (scm_list_2 (scm_variable_ref (load_path_var),
+                                      addition)));
+    }
+
+  if (load_compiled_path != NULL)
+    {
+      setenv ("GUILE_LOAD_COMPILED_PATH", load_compiled_path, 1);
+      SCM load_compiled_path_var =
+       scm_c_public_lookup ("guile", "%load-compiled-path");
+      SCM addition =
+       scm_parse_path (scm_from_locale_string (load_compiled_path), SCM_EOL);
+      scm_variable_set_x (load_compiled_path_var,
+                         scm_append
+                         (scm_list_2 (scm_variable_ref 
(load_compiled_path_var),
+                                      addition)));
+    }
+
   scm_shell (argc, argv);
 }
 
@@ -40,6 +73,15 @@ main (int argc, char **argv)
        which is always preferable over the C locale.  */
     setlocale (LC_ALL, "en_US.utf8");
 
+  const char *str;
+  str = getenv ("GUILE_LOAD_PATH");
+  load_path = str != NULL ? strdup (str) : NULL;
+  str = getenv ("GUILE_LOAD_COMPILED_PATH");
+  load_compiled_path = str ? strdup (str) : NULL;
+
+  unsetenv ("GUILE_LOAD_PATH");
+  unsetenv ("GUILE_LOAD_COMPILED_PATH");
+
   scm_install_gmp_memory_functions = 1;
   scm_boot_guile (argc, argv, inner_main, 0);
   return 0; /* never reached */