;;;; -*- indent-tabs-mode: nil; outline-regexp: ";;;;;*"; -*-
;;;
;;; swank-abcl.lisp --- Armedbear CL specific code for SLIME.
;;;
;;; Adapted from swank-acl.lisp, Andras Simon, 2004
;;;
;;; This code has been placed in the Public Domain.  All warranties
;;; are disclaimed.
;;;

(defpackage swank/abcl
  (:use cl swank/backend))

(in-package swank/abcl)

(eval-when (:compile-toplevel :load-toplevel :execute)
  (require :collect) ;just so that it doesn't spoil the flying letters
  (require :pprint)
  (require :gray-streams)
  (assert (>= (read-from-string (subseq (lisp-implementation-version) 0 4))
              0.22)
          () "This file needs ABCL version 0.22 or newer"))

(defimplementation gray-package-name ()
  "GRAY-STREAMS")

;; FIXME: switch to shared Gray stream implementation when bugs are
;; fixed in ABCL.  See: http://abcl.org/trac/ticket/373.
(progn
  (defimplementation make-output-stream (write-string)
    (ext:make-slime-output-stream write-string))

  (defimplementation make-input-stream (read-string)
    (ext:make-slime-input-stream read-string
                                 (make-synonym-stream '*standard-output*))))

(defimplementation call-with-compilation-hooks (function)
  (funcall function))

;;; swank-mop

;;dummies and definition

(defclass standard-slot-definition ()())

;(defun class-finalized-p (class) t)

(defun slot-definition-documentation (slot)
  (declare (ignore slot))
  #+nil (documentation slot 't))

(defun slot-definition-type (slot)
  (declare (ignore slot))
  t)

(defun class-prototype (class)
  (declare (ignore class))
  nil)

(defun generic-function-declarations (gf)
  (declare (ignore gf))
  nil)

(defun specializer-direct-methods (spec)
  (mop:class-direct-methods spec))

(defun slot-definition-name (slot)
  (mop:slot-definition-name slot))

(defun class-slots (class)
  (mop:class-slots class))

(defun method-generic-function (method)
  (mop:method-generic-function method))

(defun method-function (method)
  (mop:method-function method))

(defun slot-boundp-using-class (class object slotdef)
  (declare (ignore class))
  (system::slot-boundp object (slot-definition-name slotdef)))

(defun slot-value-using-class (class object slotdef)
  (declare (ignore class))
  (system::slot-value object (slot-definition-name slotdef)))

(import-to-swank-mop
 '( ;; classes
   cl:standard-generic-function
   standard-slot-definition ;;dummy
   cl:method
   cl:standard-class
   #+#.(swank/backend:with-symbol 'compute-applicable-methods-using-classes
         'mop)
   mop:compute-applicable-methods-using-classes
   ;; standard-class readers
   mop:class-default-initargs
   mop:class-direct-default-initargs
   mop:class-direct-slots
   mop:class-direct-subclasses
   mop:class-direct-superclasses
   mop:eql-specializer
   mop:class-finalized-p
   mop:finalize-inheritance
   cl:class-name
   mop:class-precedence-list
   class-prototype ;;dummy
   class-slots
   specializer-direct-methods
   ;; eql-specializer accessors
   mop::eql-specializer-object
   ;; generic function readers
   mop:generic-function-argument-precedence-order
   generic-function-declarations ;;dummy
   mop:generic-function-lambda-list
   mop:generic-function-methods
   mop:generic-function-method-class
   mop:generic-function-method-combination
   mop:generic-function-name
   ;; method readers
   method-generic-function
   method-function
   mop:method-lambda-list
   mop:method-specializers
   mop:method-qualifiers
   ;; slot readers
   mop:slot-definition-allocation
   slot-definition-documentation ;;dummy
   mop:slot-definition-initargs
   mop:slot-definition-initform
   mop:slot-definition-initfunction
   slot-definition-name
   slot-definition-type ;;dummy
   mop:slot-definition-readers
   mop:slot-definition-writers
   slot-boundp-using-class
   slot-value-using-class
   ))

;;;; TCP Server


(defimplementation preferred-communication-style ()
  :spawn)

(defimplementation create-socket (host port &key backlog)
  (ext:make-server-socket port))

(defimplementation local-port (socket)
  (java:jcall (java:jmethod "java.net.ServerSocket" "getLocalPort") socket))

(defimplementation close-socket (socket)
  (ext:server-socket-close socket))

(defimplementation accept-connection (socket
                                      &key external-format buffering timeout)
  (declare (ignore buffering timeout))
  (ext:get-socket-stream (ext:socket-accept socket)
                         :element-type (if external-format
                                           'character
                                           '(unsigned-byte 8))
                         :external-format (or external-format :default)))

;;;; UTF8

;; faster please!
(defimplementation string-to-utf8 (s)
  (jbytes-to-octets
   (java:jcall
    (java:jmethod "java.lang.String" "getBytes" "java.lang.String")
    s
    "UTF8")))

(defimplementation utf8-to-string (u)
  (java:jnew
   (java:jconstructor "org.armedbear.lisp.SimpleString"
                      "java.lang.String")
   (java:jnew (java:jconstructor "java.lang.String" "[B" "java.lang.String")
              (octets-to-jbytes u)
              "UTF8")))

(defun octets-to-jbytes (octets)
  (declare (type octets (simple-array (unsigned-byte 8) (*))))
  (let* ((len (length octets))
         (bytes (java:jnew-array "byte" len)))
    (loop for byte across octets
          for i from 0
          do (java:jstatic (java:jmethod "java.lang.reflect.Array"  "setByte"
                            "java.lang.Object" "int" "byte")
                           "java.lang.relect.Array"
                           bytes i byte))
    bytes))

(defun jbytes-to-octets (jbytes)
  (let* ((len (java:jarray-length jbytes))
         (octets (make-array len :element-type '(unsigned-byte 8))))
    (loop for i from 0 below len
          for jbyte = (java:jarray-ref jbytes i)
          do (setf (aref octets i) jbyte))
    octets))

;;;; External formats

(defvar *external-format-to-coding-system*
  '((:iso-8859-1 "latin-1" "iso-latin-1" "iso-8859-1")
    ((:iso-8859-1 :eol-style :lf)
     "latin-1-unix" "iso-latin-1-unix" "iso-8859-1-unix")
    (:utf-8 "utf-8")
    ((:utf-8 :eol-style :lf) "utf-8-unix")
    (:euc-jp "euc-jp")
    ((:euc-jp :eol-style :lf) "euc-jp-unix")
    (:us-ascii "us-ascii")
    ((:us-ascii :eol-style :lf) "us-ascii-unix")))

(defimplementation find-external-format (coding-system)
  (car (rassoc-if (lambda (x)
                    (member coding-system x :test #'equal))
                  *external-format-to-coding-system*)))

;;;; Unix signals

(defimplementation getpid ()
  (handler-case
      (let* ((runtime
              (java:jstatic "getRuntime" "java.lang.Runtime"))
             (command
              (java:jnew-array-from-array
               "java.lang.String" #("sh" "-c" "echo $PPID")))
             (runtime-exec-jmethod
              ;; Complicated because java.lang.Runtime.exec() is
              ;; overloaded on a non-primitive type (array of
              ;; java.lang.String), so we have to use the actual
              ;; parameter instance to get java.lang.Class
              (java:jmethod "java.lang.Runtime" "exec"
                            (java:jcall
                             (java:jmethod "java.lang.Object" "getClass")
                             command)))
             (process
              (java:jcall runtime-exec-jmethod runtime command))
             (output
              (java:jcall (java:jmethod "java.lang.Process" "getInputStream")
                          process)))
         (java:jcall (java:jmethod "java.lang.Process" "waitFor")
                     process)
	 (loop :with b :do
	    (setq b
		  (java:jcall (java:jmethod "java.io.InputStream" "read")
			      output))
	    :until (member b '(-1 #x0a))	; Either EOF or LF
	    :collecting (code-char b) :into result
	    :finally (return
		       (parse-integer (coerce result 'string)))))
    (t () 0)))

(defimplementation lisp-implementation-type-name ()
  "armedbear")

(defimplementation set-default-directory (directory)
  (let ((dir (sys::probe-directory directory)))
    (when dir (setf *default-pathname-defaults* dir))
    (namestring dir)))


;;;; Misc

(defimplementation arglist (fun)
  (cond ((symbolp fun)
          (multiple-value-bind (arglist present)
              (sys::arglist fun)
            (when (and (not present)
                       (fboundp fun)
                       (typep (symbol-function fun)
                              'standard-generic-function))
              (setq arglist
                    (mop::generic-function-lambda-list (symbol-function fun))
                    present
                    t))
            (if present arglist :not-available)))
        (t :not-available)))

(defimplementation function-name (function)
  (nth-value 2 (function-lambda-expression function)))

(defimplementation macroexpand-all (form)
  (macroexpand form))

(defimplementation describe-symbol-for-emacs (symbol)
  (let ((result '()))
    (flet ((doc (kind &optional (sym symbol))
             (or (documentation sym kind) :not-documented))
           (maybe-push (property value)
             (when value
               (setf result (list* property value result)))))
      (maybe-push
       :variable (when (boundp symbol)
                   (doc 'variable)))
      (when (fboundp symbol)
        (maybe-push
         (cond ((macro-function symbol)     :macro)
	       ((special-operator-p symbol) :special-operator)
	       ((typep (fdefinition symbol) 'generic-function)
                :generic-function)
	       (t :function))
         (doc 'function)))
      (maybe-push
       :class (if (find-class symbol nil)
                  (doc 'class)))
      result)))

(defimplementation describe-definition (symbol namespace)
  (ecase namespace
    ((:variable :macro)
     (describe symbol))
    ((:function :generic-function)
     (describe (symbol-function symbol)))
    (:class
     (describe (find-class symbol)))))

(defimplementation describe-definition (symbol namespace)
  (ecase namespace
    (:variable
     (describe symbol))
    ((:function :generic-function)
     (describe (symbol-function symbol)))
    (:class
     (describe (find-class symbol)))))


;;;; Debugger

;; Copied from swank-sbcl.lisp.
;;
;; Notice that *INVOKE-DEBUGGER-HOOK* is tried before *DEBUGGER-HOOK*,
;; so we have to make sure that the latter gets run when it was
;; established locally by a user (i.e. changed meanwhile.)
(defun make-invoke-debugger-hook (hook)
  (lambda (condition old-hook)
    (if *debugger-hook*
        (funcall *debugger-hook* condition old-hook)
        (funcall hook condition old-hook))))

(defimplementation call-with-debugger-hook (hook fun)
  (let ((*debugger-hook* hook)
        (sys::*invoke-debugger-hook* (make-invoke-debugger-hook hook)))
    (funcall fun)))

(defimplementation install-debugger-globally (function)
  (setq *debugger-hook* function)
  (setq sys::*invoke-debugger-hook* (make-invoke-debugger-hook function)))

(defvar *sldb-topframe*)

(defimplementation call-with-debugging-environment (debugger-loop-fn)
  (let* ((magic-token (intern "SWANK-DEBUGGER-HOOK" 'swank))
         (*sldb-topframe*
          (second (member magic-token (sys:backtrace)
                          :key (lambda (frame)
                                 (first (sys:frame-to-list frame)))))))
    (funcall debugger-loop-fn)))

(defun backtrace (start end)
  "A backtrace without initial SWANK frames."
  (let ((backtrace (sys:backtrace)))
    (subseq (or (member *sldb-topframe* backtrace) backtrace)
            start end)))

(defun nth-frame (index)
  (nth index (backtrace 0 nil)))

(defimplementation compute-backtrace (start end)
  (let ((end (or end most-positive-fixnum)))
    (backtrace start end)))

(defimplementation print-frame (frame stream)
  (write-string (sys:frame-to-string frame)
                stream))

;;; Sorry, but can't seem to declare DEFIMPLEMENTATION under FLET.
;;; --ME 20150403
(defun nth-frame-list (index)
  (java:jcall "toLispList" (nth-frame index)))

(defun match-lambda (operator values)
  (jvm::match-lambda-list
   (multiple-value-list
    (jvm::parse-lambda-list (ext:arglist operator)))
   values))

(defimplementation frame-locals (index)
  (loop
     :for id :upfrom 0
     :with frame = (nth-frame-list index)
     :with operator = (first frame)
     :with values = (rest frame)
     :with arglist = (if (and operator (consp values) (not (null values)))
                         (handler-case
                             (match-lambda operator values)
                           (jvm::lambda-list-mismatch (e)
                             :lambda-list-mismatch))
                         :not-available)
     :for value :in values
     :collecting (list
                  :name (if (not (keywordp arglist))
                            (first (nth id arglist))
                            (format nil "arg~A" id))
                  :id id
                  :value value)))

(defimplementation frame-var-value (index id)
  (elt (rest (java:jcall "toLispList" (nth-frame index))) id))


#+nil
(defimplementation disassemble-frame (index)
  (disassemble (debugger:frame-function (nth-frame index))))

(defimplementation frame-source-location (index)
  (let ((frame (nth-frame index)))
    (or (source-location (nth-frame index))
        `(:error ,(format nil "No source for frame: ~a" frame)))))

#+nil
(defimplementation eval-in-frame (form frame-number)
  (debugger:eval-form-in-context
   form
   (debugger:environment-of-frame (nth-frame frame-number))))

#+nil
(defimplementation return-from-frame (frame-number form)
  (let ((frame (nth-frame frame-number)))
    (multiple-value-call #'debugger:frame-return
      frame (debugger:eval-form-in-context
             form
             (debugger:environment-of-frame frame)))))

;;; XXX doesn't work for frames with arguments
#+nil
(defimplementation restart-frame (frame-number)
  (let ((frame (nth-frame frame-number)))
    (debugger:frame-retry frame (debugger:frame-function frame))))

;;;; Compiler hooks

(defvar *buffer-name* nil)
(defvar *buffer-start-position*)
(defvar *buffer-string*)
(defvar *compile-filename*)

(defvar *abcl-signaled-conditions*)

(defun handle-compiler-warning (condition)
  (let ((loc (when (and jvm::*compile-file-pathname*
                        system::*source-position*)
               (cons jvm::*compile-file-pathname* system::*source-position*))))
    ;; filter condition signaled more than once.
    (unless (member condition *abcl-signaled-conditions*)
      (push condition *abcl-signaled-conditions*)
      (signal 'compiler-condition
              :original-condition condition
              :severity :warning
              :message (format nil "~A" condition)
              :location (cond (*buffer-name*
                               (make-location
                                (list :buffer *buffer-name*)
                                (list :offset *buffer-start-position* 0)))
                              (loc
                               (destructuring-bind (file . pos) loc
                                 (make-location
                                  (list :file (namestring (truename file)))
                                  (list :position (1+ pos)))))
                              (t
                               (make-location
                                (list :file (namestring *compile-filename*))
                                (list :position 1))))))))

(defimplementation swank-compile-file (input-file output-file
                                       load-p external-format
                                       &key policy)
  (declare (ignore external-format policy))
  (let ((jvm::*resignal-compiler-warnings* t)
        (*abcl-signaled-conditions* nil))
    (handler-bind ((warning #'handle-compiler-warning))
      (let ((*buffer-name* nil)
            (*compile-filename* input-file))
        (multiple-value-bind (fn warn fail)
            (compile-file input-file :output-file output-file)
          (values fn warn
                  (and fn load-p
                       (not (load fn)))))))))

(defimplementation swank-compile-string (string &key buffer position filename
                                         policy)
  (declare (ignore filename policy))
  (let ((jvm::*resignal-compiler-warnings* t)
        (*abcl-signaled-conditions* nil))
    (handler-bind ((warning #'handle-compiler-warning))
      (let ((*buffer-name* buffer)
            (*buffer-start-position* position)
            (*buffer-string* string))
        (funcall (compile nil (read-from-string
                               (format nil "(~S () ~A)" 'lambda string))))
        t))))

#|
;;;; Definition Finding

(defun find-fspec-location (fspec type)
  (let ((file (excl::fspec-pathname fspec type)))
    (etypecase file
      (pathname
       (let ((start (scm:find-definition-in-file fspec type file)))
         (make-location (list :file (namestring (truename file)))
                        (if start
                            (list :position (1+ start))
                            (list :function-name (string fspec))))))
      ((member :top-level)
       (list :error (format nil "Defined at toplevel: ~A" fspec)))
      (null
       (list :error (format nil "Unkown source location for ~A" fspec))))))

(defun fspec-definition-locations (fspec)
  (let ((defs (excl::find-multiple-definitions fspec)))
    (loop for (fspec type) in defs
          collect (list fspec (find-fspec-location fspec type)))))

(defimplementation find-definitions (symbol)
  (fspec-definition-locations symbol))
|#

(defgeneric source-location (object))

(defmethod source-location ((symbol symbol))
  (when (pathnamep (ext:source-pathname symbol))
    (let ((pos (ext:source-file-position symbol)))
      `(:location
        (:file ,(namestring (ext:source-pathname symbol)))
        ,(if pos
             (list :position (1+ pos))
             (list :function-name (string symbol)))
        (:align t)))))

(defmethod source-location ((frame sys::java-stack-frame))
  (destructuring-bind (&key class method file line) (sys:frame-to-list frame)
    (declare (ignore method))
    (let ((file (or (find-file-in-path file *source-path*)
                    (let ((f (format nil "~{~a/~}~a"
                                     (butlast (split-string class "\\."))
                                     file)))
                      (find-file-in-path f *source-path*)))))
      (and file
           `(:location ,file (:line ,line) ())))))

(defmethod source-location ((frame sys::lisp-stack-frame))
  (destructuring-bind (operator &rest args) (sys:frame-to-list frame)
    (declare (ignore args))
    (etypecase operator
      (function (source-location operator))
      (list nil)
      (symbol (source-location operator)))))

(defmethod source-location ((fun function))
  (let ((name (function-name fun)))
    (and name (source-location name))))

(defun system-property (name)
  (java:jstatic "getProperty" "java.lang.System" name))

(defun pathname-parent (pathname)
  (make-pathname :directory (butlast (pathname-directory pathname))))

(defun pathname-absolute-p (pathname)
  (eq (car (pathname-directory pathname)) ':absolute))

(defun split-string (string regexp)
  (coerce
   (java:jcall (java:jmethod "java.lang.String" "split" "java.lang.String")
               string regexp)
   'list))

(defun path-separator ()
  (java:jfield "java.io.File" "pathSeparator"))

(defun search-path-property (prop-name)
  (let ((string (system-property prop-name)))
    (and string
         (remove nil
                 (mapcar #'truename
                         (split-string string (path-separator)))))))

(defun jdk-source-path ()
  (let* ((jre-home (truename (system-property "java.home")))
         (src-zip (merge-pathnames "src.zip" (pathname-parent jre-home)))
         (truename (probe-file src-zip)))
    (and truename (list truename))))

(defun class-path ()
  (append (search-path-property "java.class.path")
          (search-path-property "sun.boot.class.path")))

(defvar *source-path*
  (append (search-path-property "user.dir")
          (jdk-source-path)
          ;;(list (truename "/scratch/abcl/src"))
          )
  "List of directories to search for source files.")

(defun zipfile-contains-p (zipfile-name entry-name)
  (let ((zipfile (java:jnew (java:jconstructor "java.util.zip.ZipFile"
                                               "java.lang.String")
                            zipfile-name)))
    (java:jcall
     (java:jmethod "java.util.zip.ZipFile" "getEntry" "java.lang.String")
     zipfile entry-name)))

;; (find-file-in-path "java/lang/String.java" *source-path*)
;; (find-file-in-path "Lisp.java" *source-path*)

;; Try to find FILENAME in PATH.  If found, return a file spec as
;; needed by Emacs.  We also look in zip files.
(defun find-file-in-path (filename path)
  (labels ((try (dir)
             (cond ((not (pathname-type dir))
                    (let ((f (probe-file (merge-pathnames filename dir))))
                      (and f `(:file ,(namestring f)))))
                   ((equal (pathname-type dir) "zip")
                    (try-zip dir))
                   (t (error "strange path element: ~s" path))))
           (try-zip (zip)
             (let* ((zipfile-name (namestring (truename zip))))
               (and (zipfile-contains-p zipfile-name filename)
                    `(:dir ,zipfile-name  ,filename)))))
    (cond ((pathname-absolute-p filename) (probe-file filename))
          (t
           (loop for dir in path
                 if (try dir) return it)))))

(defimplementation find-definitions (symbol)
  (ext:resolve symbol)
  (let ((srcloc (source-location symbol)))
    (and srcloc `((,symbol ,srcloc)))))

#|
Uncomment this if you have patched xref.lisp, as in
http://article.gmane.org/gmane.lisp.slime.devel/2425
Also, make sure that xref.lisp is loaded by modifying the armedbear
part of *sysdep-pathnames* in swank.loader.lisp.

;;;; XREF
(setq pxref:*handle-package-forms* '(cl:in-package))

(defmacro defxref (name function)
  `(defimplementation ,name (name)
    (xref-results (,function name))))

(defxref who-calls      pxref:list-callers)
(defxref who-references pxref:list-readers)
(defxref who-binds      pxref:list-setters)
(defxref who-sets       pxref:list-setters)
(defxref list-callers   pxref:list-callers)
(defxref list-callees   pxref:list-callees)

(defun xref-results (symbols)
  (let ((xrefs '()))
    (dolist (symbol symbols)
      (push (list symbol (cadar (source-location symbol))) xrefs))
    xrefs))
|#

;;;; Inspecting
(defmethod emacs-inspect ((o t))
  (let ((parts (sys:inspected-parts o)))
    `("The object is of type " ,(symbol-name (type-of o)) "." (:newline)
      ,@(if parts
           (loop :for (label . value) :in parts
              :appending (label-value-line label value))
           (list "No inspectable parts, dumping output of CL:DESCRIBE:"
                 '(:newline)
                  (with-output-to-string (desc) (describe o desc)))))))

(defmethod emacs-inspect ((slot mop::slot-definition))
  `("Name: "
    (:value ,(mop:slot-definition-name slot))
    (:newline)
    "Documentation:" (:newline)
    ,@(when (slot-definition-documentation slot)
            `((:value ,(slot-definition-documentation slot)) (:newline)))
    "Initialization:" (:newline)
    "  Args: " (:value ,(mop:slot-definition-initargs slot)) (:newline)
    "  Form: "  ,(if (mop:slot-definition-initfunction slot)
                     `(:value ,(mop:slot-definition-initform slot))
                     "#<unspecified>") (:newline)
                     "  Function: "
                     (:value ,(mop:slot-definition-initfunction slot))
                     (:newline)))

(defmethod emacs-inspect ((f function))
  `(,@(when (function-name f)
            `("Name: "
              ,(princ-to-string (function-name f)) (:newline)))
      ,@(multiple-value-bind (args present)
                             (sys::arglist f)
                             (when present
                               `("Argument list: "
                                 ,(princ-to-string args) (:newline))))
      (:newline)
      #+nil,@(when (documentation f t)
                   `("Documentation:" (:newline)
                                      ,(documentation f t) (:newline)))
      ,@(when (function-lambda-expression f)
              `("Lambda expression:"
                (:newline) ,(princ-to-string
                             (function-lambda-expression f)) (:newline)))))

;;; Although by convention toString() is supposed to be a
;;; non-computationally expensive operation this isn't always the
;;; case, so make its computation a user interaction.
(defparameter *to-string-hashtable* (make-hash-table))
(defmethod emacs-inspect ((o java:java-object))
  (let ((to-string (lambda ()
                     (handler-case
                         (setf (gethash o *to-string-hashtable*)
                               (java:jcall "toString" o))
                       (t (e)
                         (setf (gethash o *to-string-hashtable*)
                               (format nil
                                       "Could not invoke toString(): ~A"
                                       e)))))))
    (append
     (if (gethash o *to-string-hashtable*)
         (label-value-line "toString()" (gethash o *to-string-hashtable*))
         `((:action "[compute toString()]" ,to-string) (:newline)))
     (loop :for (label . value) :in (sys:inspected-parts o)
      :appending (label-value-line label value)))))

;;;; Multithreading

(defimplementation spawn (fn &key name)
  (threads:make-thread (lambda () (funcall fn)) :name name))

(defvar *thread-plists* (make-hash-table) ; should be a weak table
  "A hashtable mapping threads to a plist.")

(defvar *thread-id-counter* 0)

(defimplementation thread-id (thread)
  (threads:synchronized-on *thread-plists*
    (or (getf (gethash thread *thread-plists*) 'id)
        (setf (getf (gethash thread *thread-plists*) 'id)
              (incf *thread-id-counter*)))))

(defimplementation find-thread (id)
  (find id (all-threads)
        :key (lambda (thread)
               (getf (gethash thread *thread-plists*) 'id))))

(defimplementation thread-name (thread)
  (threads:thread-name thread))

(defimplementation thread-status (thread)
  (format nil "Thread is ~:[dead~;alive~]" (threads:thread-alive-p thread)))

(defimplementation make-lock (&key name)
  (declare (ignore name))
  (threads:make-thread-lock))

(defimplementation call-with-lock-held (lock function)
  (threads:with-thread-lock (lock) (funcall function)))

(defimplementation current-thread ()
  (threads:current-thread))

(defimplementation all-threads ()
  (copy-list (threads:mapcar-threads #'identity)))

(defimplementation thread-alive-p (thread)
  (member thread (all-threads)))

(defimplementation interrupt-thread (thread fn)
  (threads:interrupt-thread thread fn))

(defimplementation kill-thread (thread)
  (threads:destroy-thread thread))

(defstruct mailbox
  (queue '()))

(defun mailbox (thread)
  "Return THREAD's mailbox."
  (threads:synchronized-on *thread-plists*
    (or (getf (gethash thread *thread-plists*) 'mailbox)
        (setf (getf (gethash thread *thread-plists*) 'mailbox)
              (make-mailbox)))))

(defimplementation send (thread message)
  (let ((mbox (mailbox thread)))
    (threads:synchronized-on mbox
      (setf (mailbox-queue mbox)
            (nconc (mailbox-queue mbox) (list message)))
      (threads:object-notify-all mbox))))

(defimplementation receive-if (test &optional timeout)
  (let* ((mbox (mailbox (current-thread))))
    (assert (or (not timeout) (eq timeout t)))
    (loop
     (check-slime-interrupts)
     (threads:synchronized-on mbox
       (let* ((q (mailbox-queue mbox))
              (tail (member-if test q)))
         (when tail
           (setf (mailbox-queue mbox) (nconc (ldiff q tail) (cdr tail)))
           (return (car tail)))
         (when (eq timeout t) (return (values nil t)))
         (threads:object-wait mbox 0.3))))))

(defimplementation quit-lisp ()
  (ext:exit))
