Use Gnulib forkpty()

1 files changed, 148 insertions, 0 deletions

diff --git a/m4/pty.m4 b/m4/pty.m4
new file mode 100644
index 00000000..c68cca75
--- /dev/null
+++ b/m4/pty.m4
@@ -0,0 +1,148 @@
+# pty.m4 serial 13
+dnl Copyright (C) 2010-2014 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+# gl_PTY_LIB
+# ----------
+# Define automake variable PTY_LIB to the library needed (if any).
+AC_DEFUN([gl_PTY_LIB],
+[
+  # Check for the library required for forkpty.
+  PTY_LIB=
+  save_LIBS="$LIBS"
+  AC_SEARCH_LIBS([forkpty], [util],
+    [if test "$ac_cv_search_forkpty" != "none required"; then
+       PTY_LIB="$ac_cv_search_forkpty"
+     fi])
+  LIBS="$save_LIBS"
+  AC_SUBST([PTY_LIB])
+])
+
+AC_DEFUN([gl_FUNC_FORKPTY],
+[
+  AC_REQUIRE([gl_PTY_LIB])
+  AC_REQUIRE([gl_PTY_H])
+
+  dnl We assume that forkpty exists (possibly in libc, possibly in libutil)
+  dnl if and only if it is declared.
+  AC_CHECK_DECLS([forkpty],,, [[
+/* <sys/types.h> is a prerequisite of <libutil.h> on FreeBSD 8.0.  */
+#include <sys/types.h>
+#if HAVE_PTY_H
+# include <pty.h>
+#endif
+#if HAVE_UTIL_H
+# include <util.h>
+#endif
+#if HAVE_LIBUTIL_H
+# include <libutil.h>
+#endif
+]])
+  if test $ac_cv_have_decl_forkpty = yes; then
+    dnl The system has forkpty.
+    dnl Prefer glibc's const-safe prototype, if available.
+    AC_CACHE_CHECK([for const-safe forkpty signature],
+      [gl_cv_func_forkpty_const],
+      [AC_COMPILE_IFELSE(
+        [AC_LANG_PROGRAM([[
+/* <sys/types.h> is a prerequisite of <libutil.h> on FreeBSD 8.0.  */
+#include <sys/types.h>
+#if HAVE_PTY_H
+# include <pty.h>
+#endif
+#if HAVE_UTIL_H
+# include <util.h>
+#endif
+#if HAVE_LIBUTIL_H
+# include <libutil.h>
+#endif
+          ]], [[
+            int forkpty (int *, char *, struct termios const *,
+                         struct winsize const *);
+          ]])
+        ],
+        [gl_cv_func_forkpty_const=yes], [gl_cv_func_forkpty_const=no])
+      ])
+    if test $gl_cv_func_forkpty_const != yes; then
+      REPLACE_FORKPTY=1
+    fi
+  else
+    dnl The system does not have forkpty.
+    HAVE_FORKPTY=0
+  fi
+  AC_DEFINE_UNQUOTED([HAVE_FORKPTY], [$HAVE_FORKPTY],
+    [Define to 1 if the system has the 'forkpty' function.])
+])
+
+AC_DEFUN([gl_FUNC_OPENPTY],
+[
+  AC_REQUIRE([gl_PTY_LIB])
+  AC_REQUIRE([gl_PTY_H])
+
+  dnl Persuade Solaris <stdlib.h> to declare posix_openpt().
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
+
+  dnl We assume that openpty exists (possibly in libc, possibly in libutil)
+  dnl if and only if it is declared.
+  AC_CHECK_DECLS([openpty],,, [[
+/* <sys/types.h> is a prerequisite of <libutil.h> on FreeBSD 8.0.  */
+#include <sys/types.h>
+#if HAVE_PTY_H
+# include <pty.h>
+#endif
+#if HAVE_UTIL_H
+# include <util.h>
+#endif
+#if HAVE_LIBUTIL_H
+# include <libutil.h>
+#endif
+]])
+  if test $ac_cv_have_decl_openpty = yes; then
+    AC_DEFINE([HAVE_OPENPTY], [1],
+      [Define to 1 if the system has the 'openpty' function.])
+    dnl The system has openpty.
+    dnl Prefer glibc's const-safe prototype, if available.
+    AC_CACHE_CHECK([for const-safe openpty signature],
+      [gl_cv_func_openpty_const],
+      [AC_COMPILE_IFELSE(
+        [AC_LANG_PROGRAM([[
+/* <sys/types.h> is a prerequisite of <libutil.h> on FreeBSD 8.0.  */
+#include <sys/types.h>
+#if HAVE_PTY_H
+# include <pty.h>
+#endif
+#if HAVE_UTIL_H
+# include <util.h>
+#endif
+#if HAVE_LIBUTIL_H
+# include <libutil.h>
+#endif
+          ]], [[
+            int openpty (int *, int *, char *, struct termios const *,
+                       struct winsize const *);
+          ]])
+        ],
+        [gl_cv_func_openpty_const=yes], [gl_cv_func_openpty_const=no])
+      ])
+    if test $gl_cv_func_openpty_const != yes; then
+      REPLACE_OPENPTY=1
+    fi
+  else
+    dnl The system does not have openpty.
+    HAVE_OPENPTY=0
+    dnl Prerequisites of lib/openpty.c in this case.
+    AC_CHECK_FUNCS([_getpty posix_openpt])
+  fi
+])
+
+AC_DEFUN([gl_FUNC_LOGIN_TTY],
+[
+  AC_REQUIRE([gl_PTY_LIB])
+
+  gl_saved_libs="$LIBS"
+  LIBS="$LIBS $PTY_LIB"
+  AC_CHECK_FUNCS([login_tty])
+  LIBS="$gl_saved_LIBS"
+])