pty: improve replacement header

Build pty.h in the same way as all other replacement headers.

* lib/pty.in.h: New file.
* modules/pty (Files): Ship it.
(Makefile.am): Always build replacement.
* m4/pty.m4: Rename...
* m4/pty_h.m4: ...to this.
(gl_PTY): Modernize setting of witness macros; update check of
forkpty to take proper advantage of cache.
(gl_PTY_MODULE_INDICATOR, gl_PTY_H_DEFAULTS): New macros.

Signed-off-by: Eric Blake <eblake@redhat.com>

diff --git a/ChangeLog b/ChangeLog
index 6788707..bbb0444 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
 2010-03-19  Eric Blake  <eblake@redhat.com>
 
+       pty: improve replacement header
+       * lib/pty.in.h: New file.
+       * modules/pty (Files): Ship it.
+       (Makefile.am): Always build replacement.
+       * m4/pty.m4: Rename...
+       * m4/pty_h.m4: ...to this.
+       (gl_PTY): Modernize setting of witness macros; update check of
+       forkpty to take proper advantage of cache.
+       (gl_PTY_MODULE_INDICATOR, gl_PTY_H_DEFAULTS): New macros.
+
        getopt: avoid compiler warning
        * lib/getopt.c (attribute_hidden): Remove unused macro.
 

diff --git a/lib/pty.in.h b/lib/pty.in.h
new file mode 100644 (file)
index 0000000..8d80f8a
--- /dev/null
+++ b/lib/pty.in.h
@@ -0,0 +1,67 @@
+/* Substitute for and wrapper around <pty.h>.
+   Copyright (C) 2010 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+#ifndef _GL_PTY_H
+
+#if __GNUC__ >= 3
+@PRAGMA_SYSTEM_HEADER@
+#endif
+
+/* The include_next requires a split double-inclusion guard.  */
+#if @HAVE_PTY_H@
+# @INCLUDE_NEXT@ @NEXT_PTY_H@
+#endif
+
+#ifndef _GL_PTY_H
+#define _GL_PTY_H
+
+/* Some platforms declare this in a different header than glibc.  */
+#if @HAVE_UTIL_H@
+# include <util.h>
+#endif
+#if @HAVE_LIBUTIL_H@
+# include <libutil.h>
+#endif
+
+/* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
+
+/* The definition of _GL_WARN_ON_USE is copied here.  */
+
+
+/* Declare overridden functions.  */
+
+#if 1 /* FIXME - split forkpty into separate module */
+#elif defined GNULIB_POSIXCHECK
+# undef forkpty
+# if HAVE_RAW_DECL_FORKPTY
+_GL_WARN_ON_USE (forkpty, "forkpty is not declared consistently - "
+                 "use gnulib module pty for portability");
+# endif
+#endif
+
+#if 1 /* FIXME - split openpty into separate module */
+#elif defined GNULIB_POSIXCHECK
+# undef openpty
+# if HAVE_RAW_DECL_OPENPTY
+_GL_WARN_ON_USE (openpty, "openpty is not declared consistently - "
+                 "use gnulib module pty for portability");
+# endif
+#endif
+
+
+#endif /* _GL_PTY_H */
+#endif /* _GL_PTY_H */

diff --git a/m4/pty.m4 b/m4/pty.m4
deleted file mode 100644 (file)
index 35ff929..0000000
--- a/m4/pty.m4
+++ /dev/null
@@ -1,43 +0,0 @@
-# pty.m4 serial 1
-dnl Copyright (C) 2009, 2010 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
-# ------
-# Make sure that pty.h provides forkpty, or sets up a replacement header.
-# Also define automake variable PTY_LIB to the library needed (if any).
-AC_DEFUN([gl_PTY],
-[
-  PTY_H=''
-  PTY_LIB=''
-  # First make sure that pty.h provides forkpty, or setup the replacement.
-  AC_CHECK_HEADERS_ONCE([pty.h])
-  if test $ac_cv_header_pty_h != yes; then
-    AC_CHECK_DECL([forkpty],,, [[#include <util.h>]])
-    if test $ac_cv_have_decl_forkpty = no; then
-      unset ac_cv_have_decl_forkpty
-      AC_CHECK_DECL([forkpty],,, [[#include <libutil.h>]])
-      if test $ac_cv_have_decl_forkpty = no; then
-        AC_MSG_WARN([[Cannot find forkpty, build will likely fail]])
-      else
-        PTY_H='pty.h'
-        PTY_HEADER='libutil.h'
-      fi
-    else
-      PTY_H='pty.h'
-      PTY_HEADER='util.h'
-    fi
-  fi
-  # Second check for the library required for forkpty.
-  save_LIBS="$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_H])
-  AC_SUBST([PTY_LIB])
-  AC_SUBST([PTY_HEADER])
-])

diff --git a/m4/pty_h.m4 b/m4/pty_h.m4
new file mode 100644 (file)
index 0000000..3b6d910
--- /dev/null
+++ b/m4/pty_h.m4
@@ -0,0 +1,81 @@
+# pty_h.m4 serial 2
+dnl Copyright (C) 2009, 2010 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
+# ------
+# Make sure that pty.h provides forkpty, or sets up a replacement header.
+# Also define automake variable PTY_LIB to the library needed (if any).
+AC_DEFUN_ONCE([gl_PTY],
+[
+  AC_REQUIRE([gl_PTY_H_DEFAULTS])
+
+  PTY_LIB=''
+  # First make sure that pty.h provides forkpty, or setup the replacement.
+  AC_CHECK_HEADERS_ONCE([pty.h])
+  if test $ac_cv_header_pty_h != yes; then
+    HAVE_PTY_H=0
+    AC_CHECK_HEADERS([util.h libutil.h])
+    if test $ac_cv_header_util_h = yes; then
+      HAVE_UTIL_H=1
+    fi
+    if test $ac_cv_header_libutil_h = yes; then
+      HAVE_LIBUTIL_H=1
+    fi
+    AC_CHECK_DECLS([forkpty],,, [[
+#if HAVE_UTIL_H
+# include <util.h>
+#endif
+#if HAVE_LIBUTIL_H
+# include <libutil.h>
+#endif
+]])
+    if test $ac_cv_have_decl_forkpty = no; then
+      AC_MSG_WARN([[Cannot find forkpty, build will likely fail]])
+    fi
+  else # Have <pty.h>, assume forkpty is declared there.
+    HAVE_PTY_H=1
+  fi
+  AC_SUBST([HAVE_PTY_H])
+  dnl <pty.h> is always overridden, because of GNULIB_POSIXCHECK.
+  gl_CHECK_NEXT_HEADERS([pty.h])
+
+  # Second check for the library required for forkpty.
+  save_LIBS="$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])
+
+  dnl Check for declarations of anything we want to poison if the
+  dnl corresponding gnulib module is not in use.
+  gl_WARN_ON_USE_PREPARE([[
+#if HAVE_PTY_H
+# include <pty.h>
+#endif
+#if HAVE_UTIL_H
+# include <util.h>
+#endif
+#if HAVE_LIBUTIL_H
+# include <libutil.h>
+#endif
+    ]], [forkpty openpty])
+])
+
+AC_DEFUN([gl_PTY_MODULE_INDICATOR],
+[
+  dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
+  AC_REQUIRE([gl_PTY_H_DEFAULTS])
+  GNULIB_[]m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./-],[ABCDEFGHIJKLMNOPQRSTUVWXYZ___])=1
+])
+
+AC_DEFUN([gl_PTY_H_DEFAULTS],
+[
+  dnl Assume proper GNU behavior unless another module says otherwise.
+  HAVE_UTIL_H=0;        AC_SUBST([HAVE_UTIL_H])
+  HAVE_LIBUTIL_H=0;     AC_SUBST([HAVE_LIBUTIL_H])
+])

diff --git a/modules/pty b/modules/pty
index 66cecef..ef064be 100644 (file)
--- a/modules/pty
+++ b/modules/pty
@@ -2,22 +2,36 @@ Description:
 A <pty.h> for systems that lacks it.
 
 Files:
-m4/pty.m4
+lib/pty.in.h
+m4/pty_h.m4
+
+Depends-on:
+c++defs
+include_next
+warn-on-use
 
 configure.ac:
 gl_PTY
 
 Makefile.am:
-BUILT_SOURCES += $(PTY_H)
+BUILT_SOURCES += pty.h
 
 # We need the following in order to create <pty.h> when the system
 # doesn't have one that works with the given compiler.
-pty.h:
+pty.h: pty.in.h $(CXXDEFS_H) $(WARN_ON_USE_H)
        $(AM_V_GEN)rm -f $@-t $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
-         echo '#include <'$(PTY_HEADER)'>'; \
+         sed -e 's|@''HAVE_PTY_H''@|$(HAVE_PTY_H)|g' \
+             -e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \
+             -e 's|@''PRAGMA_SYSTEM_HEADER''@|@PRAGMA_SYSTEM_HEADER@|g' \
+             -e 's|@''NEXT_PTY_H''@|$(NEXT_PTY_H)|g' \
+             -e 's|@''HAVE_UTIL_H''@|$(HAVE_UTIL_H)|g' \
+             -e 's|@''HAVE_LIBUTIL_H''@|$(HAVE_LIBUTIL_H)|g' \
+             -e '/definitions of _GL_FUNCDECL_RPL/r $(CXXDEFS_H)' \
+             -e '/definition of _GL_WARN_ON_USE/r $(WARN_ON_USE_H)' \
+             < $(srcdir)/pty.in.h; \
        } > $@-t && \
-       mv -f $@-t $@
+       mv $@-t $@
 MOSTLYCLEANFILES += pty.h pty.h-t
 
 Include: