From: Michael Tremer <michael.tremer@ipfire.org>
Date: Sun, 6 Oct 2024 13:46:21 +0000 (+0000)
Subject: pty: Implement draining the buffers
X-Git-Tag: 0.9.30~1138
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=93bd0b9559f56796127317408dfcc4f763a26233;p=pakfire.git

pty: Implement draining the buffers

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/libpakfire/include/pakfire/pty.h b/src/libpakfire/include/pakfire/pty.h
index f3f394227..0a49965a2 100644
--- a/src/libpakfire/include/pakfire/pty.h
+++ b/src/libpakfire/include/pakfire/pty.h
@@ -41,5 +41,7 @@ struct pakfire_pty* pakfire_pty_unref(struct pakfire_pty* pty);
 
 int pakfire_pty_open(struct pakfire_pty* pty);
 
+int pakfire_pty_drain(struct pakfire_pty* pty);
+
 #endif /* PAKFIRE_PRIVATE */
 #endif /* PAKFIRE_PTY_H */
diff --git a/src/libpakfire/jail.c b/src/libpakfire/jail.c
index 99838e12c..f8a1040f7 100644
--- a/src/libpakfire/jail.c
+++ b/src/libpakfire/jail.c
@@ -1196,6 +1196,9 @@ static int pakfire_jail_exited(sd_event_source* source, const siginfo_t* si, voi
 			break;
 	}
 
+	// Drain the PTY
+	pakfire_pty_drain(ctx->pty);
+
 	// Terminate the event loop
 	return sd_event_exit(sd_event_source_get_event(source), 0);
 }
diff --git a/src/libpakfire/pty.c b/src/libpakfire/pty.c
index c1e963508..047477a5f 100644
--- a/src/libpakfire/pty.c
+++ b/src/libpakfire/pty.c
@@ -80,8 +80,66 @@ struct pakfire_pty {
 
 	// SIGWINCH Event
 	sd_event_source* sigwinch_event;
+
+	// State
+	enum {
+		PAKFIRE_PTY_STATE_INIT = 0,
+		PAKFIRE_PTY_STATE_FORWARDING,
+		PAKFIRE_PTY_STATE_DRAINING,
+		PAKFIRE_PTY_STATE_DONE,
+	} state;
 };
 
+static int pakfire_pty_drained(struct pakfire_pty* pty) {
+	int q;
+	int r;
+
+	// We still have data in the buffer
+	if (pty->stdout.buffered)
+		return 0;
+
+	// There is still data in the PTY buffer
+	if (pty->master.io & PAKFIRE_PTY_READY_TO_READ)
+		return 0;
+
+	// Is there anything in the input buffer?
+	r = ioctl(pty->master.fd, TIOCINQ, &q);
+	if (r < 0) {
+		CTX_DEBUG(pty->ctx, "TIOCINQ failed on master fd %d: %m\n", pty->master.fd);
+		return -errno;
+	}
+
+	if (q)
+		return 0;
+
+	// Is there anything in the output buffer?
+	r = ioctl(pty->master.fd, TIOCOUTQ, &q);
+	if (r < 0) {
+		CTX_DEBUG(pty->ctx, "TIOCOUTQ failed on master fd %d: %m\n", pty->master.fd);
+		return -errno;
+	}
+
+	if (q)
+		return 0;
+
+	// We are fully drained
+	return 1;
+}
+
+static int pakfire_pty_done(struct pakfire_pty* pty, int code) {
+	sd_event* loop = NULL;
+
+	// Don't run this more than once
+	if (pty->state == PAKFIRE_PTY_STATE_DONE)
+		return 0;
+
+	// Fetch a reference to the event loop
+	loop = sd_event_ref(pty->loop);
+
+	// Terminate the event loop
+	return sd_event_exit(loop, code < 0 ? EXIT_FAILURE : code);
+}
+
 /*
 	Reads as much data as possible into the buffer
 */
@@ -158,6 +216,16 @@ static int pakfire_pty_drain_buffer(struct pakfire_pty* pty, int fd, struct pakf
 static int pakfire_pty_forward(struct pakfire_pty* pty) {
 	int r;
 
+	// Make sure we are in the correct state
+	switch (pty->state) {
+		case PAKFIRE_PTY_STATE_FORWARDING:
+		case PAKFIRE_PTY_STATE_DRAINING:
+			break;
+
+		default:
+			return -EINVAL;
+	}
+
 	while (pty->master.io || pty->stdin.io || pty->stdout.io) {
 		// Read from standard input
 		if (pty->stdin.io & PAKFIRE_PTY_READY_TO_READ) {
@@ -218,6 +286,10 @@ static int pakfire_pty_forward(struct pakfire_pty* pty) {
 		}
 	}
 
+	// If we have been requested to drain, and are fully drained, we are done
+	if (pty->state == PAKFIRE_PTY_STATE_DRAINING && pakfire_pty_drained(pty))
+		return pakfire_pty_done(pty, 0);
+
 	return 0;
 }
 
@@ -374,6 +446,9 @@ static int pakfire_pty_setup_forwarding(struct pakfire_pty* pty) {
 
 	CTX_DEBUG(pty->ctx, "Setting up PTY Forwarding...\n");
 
+	// Mark as forwarding
+	pty->state = PAKFIRE_PTY_STATE_FORWARDING;
+
 	// Connect to standard input/output
 	pty->stdin.fd  = STDIN_FILENO;
 	pty->stdout.fd = STDOUT_FILENO;
@@ -728,3 +803,9 @@ int pakfire_pty_open(struct pakfire_pty* pty) {
 
 	return 0;
 }
+
+int pakfire_pty_drain(struct pakfire_pty* pty) {
+	pty->state = PAKFIRE_PTY_STATE_DRAINING;
+
+	return pakfire_pty_drained(pty);
+}