From: Michael Tremer <michael.tremer@ipfire.org>
Date: Sun, 6 Oct 2024 12:39:09 +0000 (+0000)
Subject: pty: Be less smart about the forwarding and make it work again
X-Git-Tag: 0.9.30~1141
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=83c0146a037c68b557e00a62eb120c0fff976477;p=pakfire.git

pty: Be less smart about the forwarding and make it work again

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

diff --git a/src/libpakfire/pty.c b/src/libpakfire/pty.c
index 098b45cd1..0d63d8bc3 100644
--- a/src/libpakfire/pty.c
+++ b/src/libpakfire/pty.c
@@ -79,70 +79,68 @@ struct pakfire_pty {
 /*
 	Reads as much data as possible into the buffer
 */
-static int pakfire_pty_fill_buffer(struct pakfire_pty* pty, struct pakfire_pty_stdio* stdio) {
+static int pakfire_pty_fill_buffer(struct pakfire_pty* pty, int fd, struct pakfire_pty_stdio* stdio) {
 	int r;
 
-	for (;;) {
-		// Skip this if there is not space left in the buffer
-		if (stdio->buffered >= sizeof(stdio->buffer))
-			return 0;
-
-		// Fill the buffer
-		r = read(stdio->fd, stdio->buffer + stdio->buffered, sizeof(stdio->buffer) - stdio->buffered);
-		if (r < 0) {
-			switch (errno) {
-				case EAGAIN:
-				case EIO:
-					return 0;
-
-				default:
-					return -errno;
-			}
+	// Skip this if there is not space left in the buffer
+	if (stdio->buffered >= sizeof(stdio->buffer))
+		return 0;
 
-		// EOF
-		} else if (r == 0) {
-			return 0;
+	// Fill the buffer
+	r = read(fd, stdio->buffer + stdio->buffered, sizeof(stdio->buffer) - stdio->buffered);
+	if (r < 0) {
+		switch (errno) {
+			case EAGAIN:
+			case EIO:
+				break;
 
-		// Successful read
-		} else {
-			stdio->buffered += r;
+			default:
+				return -errno;
 		}
+
+	// EOF
+	} else if (r == 0) {
+		return 0;
+
+	// Successful read
+	} else {
+		stdio->buffered += r;
 	}
+
+	return 0;
 }
 
 /*
 	Writes as much data as possible from the buffer
 */
-static int pakfire_pty_drain_buffer(struct pakfire_pty* pty, struct pakfire_pty_stdio* stdio) {
+static int pakfire_pty_drain_buffer(struct pakfire_pty* pty, int fd, struct pakfire_pty_stdio* stdio) {
 	int r;
 
 	// Do not try to write to an invalid file descriptor
-	if (stdio->fd < 0)
+	if (fd < 0)
 		return 0;
 
-	for (;;) {
-		// Nothing to do if the buffer is empty
-		if (!stdio->buffered)
-			return 0;
-
-		// Drain the buffer
-		r = write(stdio->fd, stdio->buffer, stdio->buffered);
-		if (r < 0) {
-			switch (errno) {
-				case EAGAIN:
-				case EIO:
-					return 0;
-
-				default:
-					return -errno;
-			}
+	// Nothing to do if the buffer is empty
+	if (!stdio->buffered)
+		return 0;
 
-		// Successful write
-		} else {
-			memmove(stdio->buffer, stdio->buffer + r, stdio->buffered - r);
+	// Drain the buffer
+	r = write(fd, stdio->buffer, stdio->buffered);
+	if (r < 0) {
+		switch (errno) {
+			case EAGAIN:
+			case EIO:
+				break;
 
-			stdio->buffered -= r;
+			default:
+				return -errno;
 		}
+
+	// Successful write
+	} else {
+		memmove(stdio->buffer, stdio->buffer + r, stdio->buffered - r);
+
+		stdio->buffered -= r;
 	}
 
 	return 0;
@@ -157,7 +155,7 @@ static int pakfire_pty_forward(struct pakfire_pty* pty) {
 	while (pty->master.io || pty->stdin.io || pty->stdout.io) {
 		// Read from standard input
 		if (pty->stdin.io & PAKFIRE_PTY_READY_TO_READ) {
-			r = pakfire_pty_fill_buffer(pty, &pty->stdin);
+			r = pakfire_pty_fill_buffer(pty, pty->stdin.fd, &pty->stdin);
 			if (r < 0) {
 				CTX_ERROR(pty->ctx, "Failed reading from standard input: %s\n", strerror(-r));
 				return r;
@@ -173,20 +171,21 @@ static int pakfire_pty_forward(struct pakfire_pty* pty) {
 
 		// Write to the master
 		if (pty->master.io & PAKFIRE_PTY_READY_TO_WRITE) {
-			r = pakfire_pty_drain_buffer(pty, &pty->master);
-			if (r) {
+			r = pakfire_pty_drain_buffer(pty, pty->master.fd, &pty->stdin);
+			if (r < 0) {
 				CTX_ERROR(pty->ctx, "Failed writing to the PTY: %s\n", strerror(-r));
 				return r;
 			}
 
 			// We are done writing for now
-			pty->master.io &= ~PAKFIRE_PTY_READY_TO_WRITE;
+			if (!pty->stdin.buffered)
+				pty->master.io &= ~PAKFIRE_PTY_READY_TO_WRITE;
 		}
 
 		// Read from the master
 		if (pty->master.io & PAKFIRE_PTY_READY_TO_READ) {
-			r = pakfire_pty_fill_buffer(pty, &pty->master);
-			if (r) {
+			r = pakfire_pty_fill_buffer(pty, pty->master.fd, &pty->stdout);
+			if (r < 0) {
 				CTX_ERROR(pty->ctx, "Failed reading from the PTY: %s\n", strerror(-r));
 				return r;
 			}
@@ -201,14 +200,15 @@ static int pakfire_pty_forward(struct pakfire_pty* pty) {
 
 		// Write to standard output
 		if (pty->stdout.io & PAKFIRE_PTY_READY_TO_WRITE) {
-			r = pakfire_pty_drain_buffer(pty, &pty->stdout);
-			if (r) {
+			r = pakfire_pty_drain_buffer(pty, pty->stdout.fd, &pty->stdout);
+			if (r < 0) {
 				CTX_ERROR(pty->ctx, "Failed writing to standard output: %s\n", strerror(-r));
 				return r;
 			}
 
 			// We are done writing for now
-			pty->stdout.io &= ~PAKFIRE_PTY_READY_TO_WRITE;
+			if (!pty->stdout.buffered)
+				pty->stdout.io &= ~PAKFIRE_PTY_READY_TO_WRITE;
 		}
 	}
 
@@ -288,6 +288,8 @@ static int pakfire_pty_enable_raw_mode(struct pakfire_pty* pty, struct pakfire_p
 	if (!isatty(stdio->fd))
 		return 0;
 
+	CTX_DEBUG(pty->ctx, "Enabling raw mode on fd %d\n", stdio->fd);
+
 	// Store flags
 	stdio->flags = fcntl(stdio->fd, F_GETFL);
 	if (stdio->flags < 0) {