Add basic support for the Heirloom Documentation Tools.

* m4/man-heirloom-nroff.m4: New file.
* configure.ac: Call MAN_PROG_HEIRLOOM_NROFF.  If successful and an
  nroff macro was found, prepend -mg -msafe -mpadj to the nroff and
  troff options.
* lib/encodings.c (charset_table) [HEIRLOOM_NROFF]: Disable latin1
  and nippon devices.
  (device_table) [HEIRLOOM_NROFF]: Add locale device.
* src/man.c (heirloom_line_length) [HEIRLOOM_NROFF]: New function.
  (add_roff_line_length): Optionally return a command, which should
  be inserted before troff.
  (add_roff_line_length) [HEIRLOOM_NROFF]: Support Heirloom, which
  needs text inserted at the start of the input.
  (make_roff_command) [HEIRLOOM_NROFF]: Use locale device instead of
  utf8 in UTF-8 locales.  Handle add_roff_line_length return value.
  Unset TROFFMACS if running setuid.
  (make_browser): Compile only if TROFF_IS_GROFF.
  (format_display): Only declare variables related to HTML output if
  TROFF_IS_GROFF.
* src/tests/zsoelim-1: Ignore .ll and .lt lines inserted by
  heirloom_line_length.
* NEWS: Document this.

1 files changed, 33 insertions, 0 deletions

diff --git a/m4/man-heirloom-nroff.m4 b/m4/man-heirloom-nroff.m4
new file mode 100644
index 00000000..85144e7f
--- /dev/null
+++ b/m4/man-heirloom-nroff.m4
@@ -0,0 +1,33 @@
+# man-heirloom-nroff.m4 serial 1
+dnl MAN_PROG_HEIRLOOM_NROFF(PROGRAM-NAME)
+dnl Check whether the given nroff program is from the Heirloom Documentation
+dnl Tools.  We do this by testing the .X number register; it should be
+dnl non-zero, and should change to a different value if the -mg option is
+dnl used to enable groff compatibility.
+AC_DEFUN([MAN_PROG_HEIRLOOM_NROFF],
+[AC_MSG_CHECKING([whether nroff is Heirloom nroff])
+
+AC_CACHE_VAL([man_cv_prog_heirloom_nroff],
+  [man_heirloom_ext_plain=`$1 2>/dev/null <<EOF | tr -d '\n'
+\\n(.X
+EOF
+`
+   man_heirloom_ext_mg=`$1 -mg 2>/dev/null <<EOF | tr -d '\n'
+\\n(.X
+EOF
+`
+   if test "x$man_heirloom_ext_plain" != 0 && \
+      test "x$man_heirloom_ext_mg" != 0 && \
+      test "x$man_heirloom_ext_plain" != "x$man_heirloom_extflag_mg"
+   then
+     man_cv_prog_heirloom_nroff=yes
+   else
+     man_cv_prog_heirloom_nroff=no
+   fi])
+
+if test "$man_cv_prog_heirloom_nroff" = "yes"
+then
+  AC_DEFINE([HEIRLOOM_NROFF], [1], [Define if nroff is Heirloom nroff.])
+fi
+AC_MSG_RESULT([$man_cv_prog_heirloom_nroff])
+])