[Guile-commits] 05/05: Load (ice-9 binary-ports) from C in thread-safe way

[Andy Wingo]

wingo pushed a commit to branch wip-custom-ports
in repository guile.

commit afb8844bc217550ee0c62963b6dfbb91015c989d
Author: Andy Wingo <wingo@pobox.com>
AuthorDate: Fri Jun 2 22:28:13 2023 +0200

    Load (ice-9 binary-ports) from C in thread-safe way
    
    * libguile/r6rs-ports.c: Do the usual dance to load
    make-custom-binary-input-port et al just once.
---
 libguile/r6rs-ports.c | 35 +++++++++++++++++++++++++++++------
 1 file changed, 29 insertions(+), 6 deletions(-)

diff --git a/libguile/r6rs-ports.c b/libguile/r6rs-ports.c
index 2e4fc9452..9664c2a90 100644
--- a/libguile/r6rs-ports.c
+++ b/libguile/r6rs-ports.c
@@ -771,11 +771,32 @@ initialize_bytevector_output_ports (void)
 
 /* Custom ports.  */
 
+static SCM make_custom_binary_input_port_var;
+static SCM make_custom_binary_output_port_var;
+static SCM make_custom_binary_input_output_port_var;
+
+static scm_i_pthread_once_t make_custom_binary_port_vars =
+  SCM_I_PTHREAD_ONCE_INIT;
+
+static void
+init_make_custom_binary_port_vars (void)
+{
+  SCM mod = scm_c_resolve_module ("ice-9 binary-ports");
+  SCM iface = scm_module_public_interface (mod);
+  make_custom_binary_input_port_var =
+    scm_c_module_lookup (iface, "make-custom-binary-input-port");
+  make_custom_binary_output_port_var =
+    scm_c_module_lookup (iface, "make-custom-binary-output-port");
+  make_custom_binary_input_output_port_var =
+    scm_c_module_lookup (iface, "make-custom-binary-input/output-port");
+}
+
 SCM scm_make_custom_binary_input_port (SCM id, SCM read_proc,
                                        SCM get_position_proc,
                                        SCM set_position_proc, SCM close_proc) {
-  return scm_call_5 (scm_c_public_ref ("ice-9 binary-ports",
-                                       "make-custom-binary-input-port"),
+  scm_i_pthread_once (&make_custom_binary_port_vars,
+                      init_make_custom_binary_port_vars);
+  return scm_call_5 (scm_variable_ref (make_custom_binary_input_port_var),
                      id, read_proc, get_position_proc, set_position_proc,
                      close_proc);
 }
@@ -783,8 +804,9 @@ SCM scm_make_custom_binary_input_port (SCM id, SCM 
read_proc,
 SCM scm_make_custom_binary_output_port (SCM id, SCM write_proc,
                                        SCM get_position_proc,
                                        SCM set_position_proc, SCM close_proc) {
-  return scm_call_5 (scm_c_public_ref ("ice-9 binary-ports",
-                                       "make-custom-binary-output-port"),
+  scm_i_pthread_once (&make_custom_binary_port_vars,
+                      init_make_custom_binary_port_vars);
+  return scm_call_5 (scm_variable_ref (make_custom_binary_output_port_var),
                      id, write_proc, get_position_proc, set_position_proc,
                      close_proc);
 }
@@ -794,8 +816,9 @@ SCM scm_make_custom_binary_input_output_port (SCM id, SCM 
read_proc,
                                               SCM get_position_proc,
                                               SCM set_position_proc,
                                               SCM close_proc) {
-  return scm_call_6 (scm_c_public_ref ("ice-9 binary-ports",
-                                       "make-custom-binary-input/output-port"),
+  scm_i_pthread_once (&make_custom_binary_port_vars,
+                      init_make_custom_binary_port_vars);
+  return scm_call_6 (scm_variable_ref 
(make_custom_binary_input_output_port_var),
                      id, read_proc, write_proc, get_position_proc,
                      set_position_proc, close_proc);
 }