From adaeb0d6d246a06cfcf4727225452cc45df72017 Mon Sep 17 00:00:00 2001
From: XANTRONIX Development <dev@xantronix.com>
Date: Thu, 3 Sep 2020 00:42:02 -0400
Subject: [PATCH] Use openpty(3) to open PTYs

Use openpty(3) to open PTYs, to achieve compatibility with OpenBSD as
posix_openpty() returns a file descriptor which does not block on
read() nor select()
---
 examples/Makefile |  2 +-
 examples/daemon.c | 49 ++++++++++++++++++++++++++++++-----------------
 src/Makefile      |  2 +-
 src/sock.c        | 19 +++++++-----------
 4 files changed, 40 insertions(+), 32 deletions(-)

diff --git a/examples/Makefile b/examples/Makefile
index ae8e0a4..e0682ad 100644
--- a/examples/Makefile
+++ b/examples/Makefile
@@ -5,7 +5,7 @@ CC		= $(CROSS)cc
 INCLUDE_PATH	= ../include
 
 CFLAGS		+= -I$(INCLUDE_PATH)
-LDFLAGS		= -L../src -lpatty
+LDFLAGS		= -L../src -lpatty -lutil
 
 EXAMPLES	= daemon connect listen ax25dump decode
 
diff --git a/examples/daemon.c b/examples/daemon.c
index 8a51fb1..72197ba 100644
--- a/examples/daemon.c
+++ b/examples/daemon.c
@@ -3,7 +3,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <stdarg.h>
-#include <termios.h>
+#include <util.h>
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -51,28 +51,39 @@ int main(int argc, char **argv) {
         usage(argc, argv, "Too many arguments provided");
     }
 
-    info.fd = strcmp(argv[1], "/dev/ptmx") == 0?
-        posix_openpt(O_RDWR | O_NOCTTY):
-        open(argv[1], O_RDWR | O_NOCTTY);
+    if (strcmp(argv[1], "/dev/ptmx") == 0) {
+        int ptysub;
+        char ptyname[256];
 
-    if (info.fd < 0) {
-        fprintf(stderr, "%s: %s: %s: %s\n",
-            argv[0], "open()", argv[1], strerror(errno));
-
-        goto error_open;
-    }
-
-    if (isatty(info.fd) && grantpt(info.fd) == 0 && unlockpt(info.fd) == 0) {
-        char *pts;
-
-        if ((pts = ptsname(info.fd)) == NULL) {
-            fprintf(stderr, "%s: %s: %s: %s\n",
-                argv[0], argv[1], "ptsname()", strerror(errno));
+        if (openpty(&info.fd, &ptysub, ptyname, NULL, NULL) < 0) {
+            fprintf(stderr, "%s: %s: %s\n",
+                argv[0], "openpty()", strerror(errno));
 
             goto error_open;
         }
 
-        fprintf(stderr, "pts %s\n", pts);
+        if (grantpt(info.fd) < 0) {
+            fprintf(stderr, "%s: %s: %s: %s\n",
+                argv[0], ptyname, "grantpt()", strerror(errno));
+
+            goto error_grantpt;
+        }
+
+        if (unlockpt(info.fd) < 0) {
+            fprintf(stderr, "%s: %s: %s: %s\n",
+                argv[0], ptyname, "unlockpt()", strerror(errno));
+
+            goto error_unlockpt;
+        }
+
+        fprintf(stderr, "pts %s\n", ptyname);
+    } else {
+        if ((info.fd = open(argv[1], O_RDWR | O_NOCTTY)) < 0) {
+            fprintf(stderr, "%s: %s: %s: %s\n",
+                argv[0], "open()", argv[1], strerror(errno));
+
+            goto error_open;
+        }
     }
 
     errno = 0;
@@ -136,6 +147,8 @@ error_daemon_init:
     patty_daemon_destroy(daemon);
 
 error_daemon_new:
+error_grantpt:
+error_unlockpt:
     close(info.fd);
 
 error_open:
diff --git a/src/Makefile b/src/Makefile
index 91e3030..8a7853d 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -5,7 +5,7 @@ HEADER_SUBDIR	= patty
 
 CC		= $(CROSS)cc
 CFLAGS		= $(CGFLAGS) -fPIC -Wall -O2 -I$(INCLUDE_PATH)
-LDFLAGS		=
+LDFLAGS		= -lutil
 
 HEADERS		= kiss.h ax25.h client.h ax25/if.h ax25/frame.h \
 		  ax25/sock.h ax25/route.h ax25/server.h daemon.h list.h \
diff --git a/src/sock.c b/src/sock.c
index 7226716..bb6b974 100644
--- a/src/sock.c
+++ b/src/sock.c
@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <util.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/socket.h>
@@ -17,10 +18,10 @@ struct slot {
 };
 
 static int bind_pty(patty_ax25_sock *sock) {
-    char *pty;
+    int ptysub;
 
-    if ((sock->fd = posix_openpt(O_RDWR | O_NOCTTY)) < 0) {
-        goto error_open;
+    if (openpty(&sock->fd, &ptysub, sock->pty, NULL, NULL) < 0) {
+        goto error_openpty;
     }
 
     if (grantpt(sock->fd) < 0) {
@@ -31,20 +32,14 @@ static int bind_pty(patty_ax25_sock *sock) {
         goto error_unlockpt;
     }
 
-    if ((pty = ptsname(sock->fd)) == NULL) {
-        goto error_ptsname;
-    }
-
-    (void)strncpy(sock->pty, pty, sizeof(sock->pty)-1);
-
     return 0;
 
-error_ptsname:
 error_unlockpt:
 error_grantpt:
-    close(sock->fd);
+    (void)close(ptysub);
+    (void)close(sock->fd);
 
-error_open:
+error_openpty:
     return -1;
 }