1 files changed, 48 insertions, 0 deletions
diff --git a/src/scm/webid-oidc/offloading.scm b/src/scm/webid-oidc/offloading.scm
new file mode 100644
index 0000000..9620193
--- /dev/null
+++ b/src/scm/webid-oidc/offloading.scm
@@ -0,0 +1,48 @@
+;; webid-oidc, implementation of the Solid specification
+;; Copyright (C) 2021  Vivien Kraus
+
+;; This program is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU Affero General Public License as
+;; published by the Free Software Foundation, either version 3 of the
+;; License, or (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU Affero General Public License for more details.
+
+;; You should have received a copy of the GNU Affero General Public License
+;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+(define-module (webid-oidc offloading)
+  #:use-module (ice-9 threads)
+  #:export (with-threads in-another-thread))
+
+(define tag (make-prompt-tag))
+
+(define (let-threads-escape thunk)
+  (call-with-prompt tag
+    (lambda ()
+      (thunk))
+    (lambda (k handle-continuation)
+      (handle-continuation k))))
+
+(define (continue-in-another-thread thunk)
+  (abort-to-prompt
+   tag
+   (lambda (continuation)
+     (call-with-new-thread
+      (lambda ()
+        (let-threads-escape
+         (lambda ()
+           (call-with-values
+               thunk
+             continuation))))))))
+
+(define-syntax-rule (with-threads body ...)
+  (let-threads-escape
+   (lambda () body ...)))
+
+(define-syntax-rule (in-another-thread body ...)
+  (continue-in-another-thread
+   (lambda () body ...)))