roken: Use ptsname_r() if we have it

configure.ac

@@ -529,7 +529,7 @@ AC_CHECK_FUNCS([				\
 	getresgid				\
 	getresuid				\
 	grantpt					\
-	ptsname					\
+	ptsname_r				\
 	rand					\
 	setitimer				\
 	setregid				\

include/config.h.w32

@@ -694,9 +694,6 @@ static const char *const rcsid[] = { (const char *)rcsid, "@(#)" msg }
 /* This option is added by the NTMakefile if we have a <pthread.h>. */
 /* #define HAVE_PTHREAD_H 1 */
 
-/* Define to 1 if you have the `ptsname' function. */
-/* #define HAVE_PTSNAME 1 */
-
 /* Define to 1 if you have the <pty.h> header file. */
 /* #define HAVE_PTY_H 1 */
 

lib/roken/rkpty.c

@@ -123,7 +123,18 @@ open_pty(void)
 #ifdef HAVE_UNLOCKPT
 		unlockpt(master);
 #endif
-		strlcpy(line, ptsname(master), sizeof(line));
+#ifdef HAVE_PTSNAME_R
+                if (ptsname_r(master, line, sizeof(line)) == -1)
+                    err("Failed to open the pty master %s", *q);
+#else
+                {
+                    char *s = ptsname(master);
+
+                    if (s == NULL)
+                        err("Failed to open the pty master %s", *q);
+                    strlcpy(line, s, sizeof(line));
+                }
+#endif
 		slave = open(line, O_RDWR);
 		if (slave < 0)
 		    errx(1, "failed to open slave when using %s", *q);