From 62419b105401d77499228ffc9c399c25c1d66be3 Mon Sep 17 00:00:00 2001
From: Witold Filipczyk <witekfl@poczta.onet.pl>
Date: Wed, 9 Sep 2020 18:08:17 +0200
Subject: [PATCH] [ctrl_z] Added code links-based for ctrl-z and fg. Refs #65

---
 src/osdep/signals.c | 32 +++++++++++++++++++++++++++++++-
 src/setup.h         |  2 ++
 2 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/src/osdep/signals.c b/src/osdep/signals.c
index b2632a53..aa4e2245 100644
--- a/src/osdep/signals.c
+++ b/src/osdep/signals.c
@@ -20,6 +20,7 @@
 
 #include "main/main.h"
 #include "main/select.h"
+#include "main/timer.h"
 #include "main/version.h"
 #include "osdep/signals.h"
 #include "terminal/kbd.h"
@@ -63,16 +64,21 @@ sig_ign(void *x)
 }
 #endif
 
+static void poll_fg(void *);
+static struct timer *fg_poll_timer = NULL;
+
 #if defined(SIGTSTP) || defined(SIGTTIN)
 static void
 sig_tstp(struct terminal *term)
 {
 #ifdef SIGSTOP
+	pid_t newpid;
 	pid_t pid = getpid();
 
 	block_itrm();
 #if defined (SIGCONT) && defined(SIGTTOU)
-	if (!fork()) {
+	newpid = fork();
+	if (!newpid) {
 		sleep(1);
 		kill(pid, SIGCONT);
 		/* Use _exit() rather than exit(), so that atexit
@@ -85,9 +91,33 @@ sig_tstp(struct terminal *term)
 #endif
 	raise(SIGSTOP);
 #endif
+	if (fg_poll_timer != NULL) kill_timer(&fg_poll_timer);
+	install_timer(&fg_poll_timer, FG_POLL_TIME, poll_fg, term);
 }
 #endif
 
+static void
+poll_fg(void *t_)
+{
+	struct terminal *t = (struct terminal *)t_;
+	int r ;
+
+	fg_poll_timer = NULL;
+	r = unblock_itrm();
+	if (r == -1) {
+		install_timer(&fg_poll_timer, FG_POLL_TIME, poll_fg, t);
+	}
+#if 0
+	if (r == -2) {
+		/* This will unblock externally spawned viewer, if it exists */
+#ifdef SIGCONT
+		EINTRLOOP(r, kill(0, SIGCONT));
+#endif
+	}
+#endif
+}
+
+
 #ifdef SIGCONT
 static void
 sig_cont(struct terminal *term)
diff --git a/src/setup.h b/src/setup.h
index 381cdb36..37bf7cdc 100644
--- a/src/setup.h
+++ b/src/setup.h
@@ -115,4 +115,6 @@
  * to fit in the screen, with this much extra space.  Try 4. */
 #define TABLE_LINE_PADDING		-1
 
+#define FG_POLL_TIME		500
+
 #endif