PATCH: configure test for pty multiplexor

[Peter Stephenson <pws@xxxxxxx>]

While I'm in the mood (but not remotely in the mood for curses
configuration), here is an attempt to make configure check for usability
of /dev/ptmx.  The tests are fairly simple and if there are systems that
use this stuff in a different way we will come unstuck.

It compiled and passed the tests on Solaris 8.  It compiled (using
/dev/ptmx) on RedHat 9, but I couldn't run the tests because the
directory is Samba-mounted and install gets upset when trying to do a
pretend install of the modules.

It compiled on Cygwin.  Various tests failed in a slightly obscure way.
However, that's my normal experience with Cygwin.  It should have been
using ptmx anyway (and still was).

I'm a little unhappy about all this pushing of streams modules, but it's
probably well enough tested that it won't actually bomb out.

Index: configure.ac
===================================================================
RCS file: /cvsroot/zsh/zsh/configure.ac,v
retrieving revision 1.5
diff -u -r1.5 configure.ac
--- configure.ac	17 Feb 2004 11:36:18 -0000	1.5
+++ configure.ac	17 Feb 2004 12:54:59 -0000
@@ -505,7 +505,8 @@
 		 limits.h fcntl.h libc.h sys/utsname.h sys/resource.h \
 		 locale.h errno.h stdio.h stdlib.h unistd.h sys/capability.h \
 		 utmp.h utmpx.h sys/types.h pwd.h grp.h poll.h sys/mman.h \
-		 netinet/in_systm.h pcre.h langinfo.h wchar.h stddef.h)
+		 netinet/in_systm.h pcre.h langinfo.h wchar.h stddef.h \
+		 sys/stropts.h)
 if test $dynamic = yes; then
   AC_CHECK_HEADERS(dlfcn.h)
   AC_CHECK_HEADERS(dl.h)
@@ -1029,7 +1030,8 @@
 	       pcre_compile pcre_study pcre_exec \
 	       nl_langinfo \
 	       erand48 open_memstream \
-	       wctomb iconv)
+	       wctomb iconv \
+	       grantpt unlockpt ptsname)
 AC_FUNC_STRCOLL
 
 dnl  Check if tgetent accepts NULL (and will allocate its own termcap buffer)
@@ -1796,6 +1798,24 @@
 zsh_CHECK_SOCKLEN_T
 
 dnl ---------------
+dnl Check for pty multiplexer for use in pty module.
+dnl We need to open it read/write, so make sure it is writeable.
+dnl Yet another test which won't work when cross-compiling.
+dnl ---------------
+AH_TEMPLATE([HAVE_DEV_PTMX],
+[Define to 1 if your system can use /dev/ptmx for creating ptys.])
+AC_CACHE_CHECK(if your system has /dev/ptmx,
+ac_cv_have_dev_ptmx,
+[if test -w /dev/ptmx; then
+  ac_cv_have_dev_ptmx=yes
+else
+  ac_cv_have_dev_ptmx=no
+fi])
+if test $ac_cv_have_dev_ptmx = yes; then
+  AC_DEFINE(HAVE_DEV_PTMX)
+fi
+
+dnl ---------------
 dnl dynamic loading
 dnl ---------------
 AH_TEMPLATE([HPUXDYNAMIC],
Index: Src/Modules/zpty.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/Modules/zpty.c,v
retrieving revision 1.27
diff -u -r1.27 zpty.c
--- Src/Modules/zpty.c	5 Feb 2003 11:57:09 -0000	1.27
+++ Src/Modules/zpty.c	17 Feb 2004 12:54:59 -0000
@@ -154,12 +154,10 @@
     return NULL;
 }
 
-/**** maybe we should use configure here */
-/**** and we certainly need more/better #if tests */
+#if defined(HAVE_DEV_PTMX) && defined(HAVE_GRANTPT) && \
+    defined(HAVE_PTSNAME) && defined(HAVE_UNLOCKPT)
 
-#if defined(__SVR4) || defined(sinix) || defined(__CYGWIN__)
-
-#if !defined(__CYGWIN__)
+#ifdef HAVE_SYS_STROPTS_H
 #include <sys/stropts.h>
 #endif
 
@@ -192,7 +190,11 @@
 	close(mfd);
 	return 1;
     }
-#if !defined(__CYGWIN__)
+#if defined(I_FIND) && defined(I_PUSH)
+    /*
+     * Use if STREAMS is available.  The test is probably OK,
+     * but we could use e.g. the sys/stropts.h test.
+     */
     if ((ret = ioctl(sfd, I_FIND, "ptem")) != 1)
        if (ret == -1 || ioctl(sfd, I_PUSH, "ptem") == -1) {
 	   close(mfd);
@@ -211,14 +213,14 @@
 	   close(sfd);
 	   return 1;
        }
-#endif /* !defined(__CYGWIN__) */
+#endif
 
     *retfd = sfd;
 
     return 0;
 }
 
-#else /* ! (defined(__SVR4) || defined(sinix) || defined(__CYGWIN__)) */
+#else /* No /dev/ptmx or no pt functions */
 
 static int
 get_pty(int master, int *retfd)
@@ -267,7 +269,7 @@
     return 1;
 }
 
-#endif /* __SVR4 */
+#endif /* /dev/ptmx or alternatives */
 
 static int
 newptycmd(char *nam, char *pname, char **args, int echo, int nblock)

-- 
Peter Stephenson <pws@xxxxxxx>                  Software Engineer
CSR Ltd., Science Park, Milton Road,
Cambridge, CB4 0WH, UK                          Tel: +44 (0)1223 692070


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