Asynchronous communication

3 files changed, 47 insertions, 18 deletions

diff --git a/vterm-module.c b/vterm-module.c
index b44fd54..a6beae1 100644
--- a/vterm-module.c
+++ b/vterm-module.c
@@ -5,10 +5,12 @@
 #else
 #  include <pty.h>
 #endif
+#include <pthread.h>
 #include <signal.h>
 #include <stdio.h>
 #include <string.h>
 #include <sys/ioctl.h>
+#include <sys/select.h>
 #include <sys/wait.h>
 #include <termios.h>
 #include <unistd.h>
@@ -16,7 +18,8 @@
 
 #define MAX(x, y) (((x) > (y)) ? (x) : (y))
 
-static size_t codepoint_to_utf8(const uint32_t codepoint, unsigned char buffer[4]) {
+static size_t codepoint_to_utf8(const uint32_t codepoint,
+                                unsigned char buffer[4]) {
   if (codepoint <= 0x7F) {
     buffer[0] = codepoint;
     return 1;
@@ -323,6 +326,7 @@ static void term_finalize(void *term) {
 static emacs_value Fvterm_new(emacs_env *env, ptrdiff_t nargs,
                               emacs_value args[], void *data) {
   struct Term *term = malloc(sizeof(struct Term));
+
   int rows = env->extract_integer(env, args[0]);
   int cols = env->extract_integer(env, args[1]);
 
@@ -365,7 +369,6 @@ static emacs_value Fvterm_new(emacs_env *env, ptrdiff_t nargs,
   termios.c_cc[VTIME] = 0;
 
   term->pid = forkpty(&term->masterfd, NULL, &termios, &size);
-
   fcntl(term->masterfd, F_SETFL, fcntl(term->masterfd, F_GETFL) | O_NONBLOCK);
 
   if (term->pid == 0) {
@@ -382,10 +385,30 @@ static emacs_value Fvterm_new(emacs_env *env, ptrdiff_t nargs,
   VTermScreen *screen = vterm_obtain_screen(term->vt);
   vterm_screen_reset(screen, 1);
 
+  pthread_t thread;
+  pthread_create(&thread, NULL, &event_loop, term);
+
   return env->make_user_ptr(env, term_finalize, term);
 }
 
-static void process_key(struct Term *term, unsigned char *key, size_t len, VTermModifier modifier) {
+static void *event_loop(void *arg) {
+  struct Term *term = arg;
+  fd_set rfds;
+
+  while (1) {
+    FD_ZERO(&rfds);
+    FD_SET(term->masterfd, &rfds);
+    if (select(term->masterfd + 1, &rfds, NULL, NULL, NULL) == 1) {
+      kill(getpid(), SIGUSR1);
+      usleep(20);
+    }
+  }
+
+  return NULL;
+}
+
+static void process_key(struct Term *term, unsigned char *key, size_t len,
+                        VTermModifier modifier) {
   if (len == 8 && memcmp(key, "<return>", len) == 0) {
     vterm_keyboard_key(term->vt, VTERM_KEY_ENTER, modifier);
   } else if (len == 11 && memcmp(key, "<backspace>", len) == 0) {
@@ -437,7 +460,7 @@ static emacs_value Fvterm_update(emacs_env *env, ptrdiff_t nargs,
   if ((len = read(term->masterfd, bytes, 4096)) > 0) {
     vterm_input_write(term->vt, bytes, len);
     vterm_redraw(term->vt, env);
-  };
+  }
 
   return env->make_integer(env, 0);
 }
diff --git a/vterm-module.h b/vterm-module.h
index 305b354..f6df00c 100644
--- a/vterm-module.h
+++ b/vterm-module.h
@@ -1,5 +1,6 @@
 #include <emacs-module.h>
 #include <inttypes.h>
+#include <semaphore.h>
 #include <stdbool.h>
 #include <vterm.h>
 
@@ -11,7 +12,8 @@ struct Term {
   pid_t pid;
 };
 
-static size_t codepoint_to_utf8(const uint32_t codepoint, unsigned char buffer[4]);
+static size_t codepoint_to_utf8(const uint32_t codepoint,
+                                unsigned char buffer[4]);
 static bool utf8_to_codepoint(const unsigned char buffer[4], const size_t len,
                               uint32_t *codepoint);
 static void bind_function(emacs_env *env, const char *name, emacs_value Sfun);
@@ -36,7 +38,9 @@ static void vterm_flush_output(struct Term *term);
 static void term_finalize(void *term);
 static emacs_value Fvterm_new(emacs_env *env, ptrdiff_t nargs,
                               emacs_value args[], void *data);
-static void process_key(struct Term *term, unsigned char *key, size_t len, VTermModifier modifier);
+static void *event_loop(void *arg);
+static void process_key(struct Term *term, unsigned char *key, size_t len,
+                        VTermModifier modifier);
 static emacs_value Fvterm_update(emacs_env *env, ptrdiff_t nargs,
                                  emacs_value args[], void *data);
 static emacs_value Fvterm_kill(emacs_env *env, ptrdiff_t nargs,
diff --git a/vterm.el b/vterm.el
index 7e43b18..6c828a2 100644
--- a/vterm.el
+++ b/vterm.el
@@ -15,9 +15,8 @@
   "Pointer to struct Term.")
 (make-variable-buffer-local 'vterm-term)
 
-(defvar vterm-timer nil
-  "Timer to update the term.")
-(make-variable-buffer-local 'vterm-timer)
+(defvar vterm-buffers nil
+  "List of active vterm-buffers.")
 
 (defvar vterm-keymap-exceptions '("C-x" "C-u" "C-g" "C-h" "M-x" "M-o")
   "Exceptions for vterm-keymap.
@@ -64,24 +63,27 @@ be send to the terminal.")
   "Create a new vterm."
   (interactive)
   (let ((buffer (generate-new-buffer "vterm")))
+    (add-to-list 'vterm-buffers buffer)
     (pop-to-buffer buffer)
-    (vterm-mode)
-    (setq vterm-timer (run-with-timer 0 .1 #'vterm-run-timer buffer))))
+    (vterm-mode)))
 
-(defun vterm-run-timer (buffer)
+(defun vterm-event ()
   "Update the vterm BUFFER."
   (interactive)
   (let ((inhibit-redisplay t)
         (inhibit-read-only t))
-    (with-current-buffer buffer
-      (unless (vterm-update vterm-term)
-        (cancel-timer vterm-timer)
-        (insert "\nProcess exited!\n\n")))))
+    (mapc (lambda (buffer)
+            (with-current-buffer buffer
+              (unless (vterm-update vterm-term)
+                (insert "\nProcess exited!\n\n"))))
+          vterm-buffers)))
+
+(define-key special-event-map [sigusr1] #'vterm-event)
 
 (defun vterm-kill-buffer-hook ()
-  "Cancel the timer and the vterm."
+  "Kill the corresponding process of vterm."
   (when (eq major-mode 'vterm-mode)
-    (cancel-timer vterm-timer)
+    (setq vterm-buffers (remove (current-buffer) vterm-buffers))
     (vterm-kill vterm-term)))
 
 (defun vterm-window-size-change (frame)