aio: implement openpty.c locally

To avoid linking with -lutil if possible

Signed-off-by: Steve Bennett <steveb@workware.net.au>

3 files changed, 77 insertions, 4 deletions

diff --git a/auto.def b/auto.def
index 93cbdbf..c3ff6e6 100644
--- a/auto.def
+++ b/auto.def
@@ -281,9 +281,6 @@ if {[have-feature fork]} {
 if {[cc-check-function-in-lib backtrace execinfo]} {
     define-append LDLIBS [get-define lib_backtrace]
 }
-if {[cc-check-function-in-lib openpty util]} {
-    define-append LDLIBS [get-define lib_openpty]
-}
 
 if {[cc-check-functions sysinfo]} {
     cc-with {-includes sys/sysinfo.h} {
@@ -573,6 +570,12 @@ if {[have-feature windows]} {
 if {[have-feature termios.h]} {
     lappend extra_objs jim-tty.o
 }
+if {[have-feature termios.h] && [cc-check-functions posix_openpt]} {
+    define-append AS_CFLAGS -DHAVE_OPENPTY
+    lappend extra_objs openpty.o
+} elseif {[have-feature util.h]} {
+    cc-check-function-in-lib openpty util
+}
 
 if {[ext-get-status regexp] in {y m}} {
     if {![have-feature regcomp]} {
diff --git a/jim-aio.c b/jim-aio.c
index bacaec6..f199433 100644
--- a/jim-aio.c
+++ b/jim-aio.c
@@ -2474,7 +2474,7 @@ static int JimAioOpenPtyCommand(Jim_Interp *interp, int argc, Jim_Obj *const *ar
         return JIM_ERR;
     }
 
-    /* Note: The replica path will be used for both handles slave */
+    /* Note: The replica path will be used for both handles */
     return JimMakeChannelPair(interp, p, Jim_NewStringObj(interp, path, -1), "aio.pty%ld", 0, 0);
     return JimMakeChannelPair(interp, p, Jim_NewStringObj(interp, path, -1), "aio.pty%ld", 0, 0);
 }
diff --git a/openpty.c b/openpty.c
new file mode 100644
index 0000000..dab65e1
--- /dev/null
+++ b/openpty.c
@@ -0,0 +1,70 @@
+/*
+ * From musl:     http://www.musl-libc.org/
+----------------------------------------------------------------------
+Copyright © 2005-2020 Rich Felker, et al.
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+----------------------------------------------------------------------
+*/
+#include <stdlib.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <termios.h>
+#include <sys/ioctl.h>
+#include <signal.h>
+#include <stdio.h>
+
+/* We implement our own openpty() on Linux so that we don't need to link against libutil */
+
+int openpty(int *pm, int *ps, char name[20], const struct termios *tio, const struct winsize *ws)
+{
+	sig_t old_signal;
+	int ret = -1;
+	int m = posix_openpt(O_RDWR|O_NOCTTY);
+	if (m < 0) return -1;
+
+	old_signal = signal(SIGCHLD, SIG_DFL);
+	if (grantpt(m) >= 0) {
+		if (unlockpt(m) >= 0) {
+			char buf[20];
+			int s;
+
+			if (!name) name = buf;
+			snprintf(name, sizeof(buf), "%s", ptsname(m));
+			if ((s = open(name, O_RDWR|O_NOCTTY)) >= 0) {
+				if (tio) tcsetattr(s, TCSANOW, tio);
+				if (ws) ioctl(s, TIOCSWINSZ, ws);
+
+				*pm = m;
+				*ps = s;
+
+				ret = 0;
+
+				return 0;
+			}
+		}
+	}
+	signal(SIGCHLD, old_signal);
+
+	if (ret) {
+		close(m);
+	}
+	return ret;
+}