1 files changed, 93 insertions, 0 deletions
diff --git a/winsup/cygwin/socket_tests/lib/pty_master_open.c b/winsup/cygwin/socket_tests/lib/pty_master_open.c
new file mode 100644
index 000000000..b0de3a1fb
--- /dev/null
+++ b/winsup/cygwin/socket_tests/lib/pty_master_open.c
@@ -0,0 +1,93 @@
+/*************************************************************************\
+*                  Copyright (C) Michael Kerrisk, 2018.                   *
+*                                                                         *
+* This program is free software. You may use, modify, and redistribute it *
+* under the terms of the GNU Lesser General Public License as published   *
+* by the Free Software Foundation, either version 3 or (at your option)   *
+* any later version. This program is distributed without any warranty.    *
+* See the files COPYING.lgpl-v3 and COPYING.gpl-v3 for details.           *
+\*************************************************************************/
+
+/* Listing 64-1 */
+
+/* pty_master_open.c
+
+   Implement our ptyMasterOpen() function, based on UNIX 98 pseudoterminals.
+   See comments below.
+
+   See also pty_master_open_bsd.c.
+*/
+#if ! defined(__sun)
+        /* Prevents ptsname() declaration being visible on Solaris 8 */
+#if ! defined(_XOPEN_SOURCE) || _XOPEN_SOURCE < 600
+#define _XOPEN_SOURCE 600
+#endif
+#endif
+#include <stdlib.h>
+#include <fcntl.h>
+#include "pty_master_open.h"            /* Declares ptyMasterOpen() */
+#include "af_unix_hdr.h"
+
+/* Some implementations don't have posix_openpt() */
+
+#if defined(__sun)                      /* Not on Solaris 8 */
+#define NO_POSIX_OPENPT
+#endif
+
+#ifdef NO_POSIX_OPENPT
+
+static int
+posix_openpt(int flags)
+{
+    return open("/dev/ptmx", flags);
+}
+
+#endif
+
+/* Open a pty master, returning file descriptor, or -1 on error.
+   On successful completion, the name of the corresponding pty
+   slave is returned in 'slaveName'. 'snLen' should be set to
+   indicate the size of the buffer pointed to by 'slaveName'. */
+
+int
+ptyMasterOpen(char *slaveName, size_t snLen)
+{
+    int masterFd, savedErrno;
+    char *p;
+
+    masterFd = posix_openpt(O_RDWR | O_NOCTTY);         /* Open pty master */
+    if (masterFd == -1)
+        return -1;
+
+    if (grantpt(masterFd) == -1) {              /* Grant access to slave pty */
+        savedErrno = errno;
+        close(masterFd);                        /* Might change 'errno' */
+        errno = savedErrno;
+        return -1;
+    }
+
+    if (unlockpt(masterFd) == -1) {             /* Unlock slave pty */
+        savedErrno = errno;
+        close(masterFd);                        /* Might change 'errno' */
+        errno = savedErrno;
+        return -1;
+    }
+
+    p = ptsname(masterFd);                      /* Get slave pty name */
+    if (p == NULL) {
+        savedErrno = errno;
+        close(masterFd);                        /* Might change 'errno' */
+        errno = savedErrno;
+        return -1;
+    }
+
+    if (strlen(p) < snLen) {
+        strncpy(slaveName, p, snLen);
+    } else {                    /* Return an error if buffer too small */
+        close(masterFd);
+        errno = EOVERFLOW;
+        return -1;
+    }
+
+    return masterFd;
+}