Added request `hpfa' to append hyphenation patterns.

* src/roff/troff/env.cc (hyphen_trie::read_patterns_file): Add
parameter `append'.
(hyphenation_patterns_file): Renamed to...
(do_hyphenation_patterns_file): This.
(hyphenation_patterns_file, hyphenation_patterns_file_append): New
functions.
(init_hyphen_requests): Updated.
* NEWS, man/groff.man, man/groff_diff.man: Document it.

5 files changed, 46 insertions, 6 deletions

diff --git a/ChangeLog b/ChangeLog
index d8b3bf03..da8c6013 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2002-03-17  Werner LEMBERG  <wl@gnu.org>
+
+	Added request `hpfa' to append hyphenation patterns.
+
+	* src/roff/troff/env.cc (hyphen_trie::read_patterns_file): Add
+	parameter `append'.
+	(hyphenation_patterns_file): Renamed to...
+	(do_hyphenation_patterns_file): This.
+	(hyphenation_patterns_file, hyphenation_patterns_file_append): New
+	functions.
+	(init_hyphen_requests): Updated.
+	* NEWS, man/groff.man, man/groff_diff.man: Document it.
+
 2002-03-16  Werner LEMBERG  <wl@gnu.org>
 
 	Added request `writec' in analogy to `tmc'.
diff --git a/NEWS b/NEWS
index 6e4e7a64..72b7ee5c 100644
--- a/NEWS
+++ b/NEWS
@@ -81,6 +81,9 @@ o Two new requests `ds1' and `as1' which are similar to `ds' and `as' but
   with compatibility mode disabled during expansion of strings defined by
   them.
 
+o The new request `hpfa' appends hyphenation patterns (`hpf' replaces
+  already existing patterns).
+
 o A new request `ami' (append macro indirect) has been added.  The first and
   second parameter of `ami' are taken from string registers rather than
   directly; this very special request is needed to make `trace.tmac'
diff --git a/man/groff.man b/man/groff.man
index 56f1e75c..cc23a86b 100644
--- a/man/groff.man
+++ b/man/groff.man
@@ -1588,6 +1588,10 @@ Set the maximum number of consecutive hyphenated lines to
 Read hyphenation patterns from
 .IR file .
 .
+.REQ .hpfa file
+Append hyphenation patterns from
+.IR file .
+.
 .REQ .hw words
 List of
 .I words
diff --git a/man/groff_diff.man b/man/groff_diff.man
index d636a764..5d1b1475 100644
--- a/man/groff_diff.man
+++ b/man/groff_diff.man
@@ -1447,7 +1447,15 @@ The
 .B hpf
 request is usually invoked by the
 .B troffrc
-file.
+file; a second call replaces the old patterns with the new ones.
+.
+.TP
+.BI hpfa\  file
+The same as
+.B hpf
+except that the hyphenation patterns from
+.I file
+are appended to the patterns already loaded in current language.
 .
 .TP
 .BI .hym\  n
diff --git a/src/roff/troff/env.cc b/src/roff/troff/env.cc
index eea8ad2e..05244767 100644
--- a/src/roff/troff/env.cc
+++ b/src/roff/troff/env.cc
@@ -3223,7 +3223,7 @@ public:
   hyphen_trie() {}
   ~hyphen_trie() {}
   void hyphenate(const char *word, int len, int *hyphens);
-  void read_patterns_file(const char *name);
+  void read_patterns_file(const char *name, int append);
 };
 
 
@@ -3426,9 +3426,10 @@ void hyphen_trie::do_delete(void *v)
   }
 }
   
-void hyphen_trie::read_patterns_file(const char *name)
+void hyphen_trie::read_patterns_file(const char *name, int append)
 {
-  clear();
+  if (!append)
+    clear();
   char buf[WORD_MAX];
   int num[WORD_MAX+1];
   errno = 0;
@@ -3520,18 +3521,28 @@ void hyphenate(hyphen_list *h, unsigned flags)
   }
 }
 
-static void hyphenation_patterns_file()
+static void do_hyphenation_patterns_file(int append)
 {
   symbol name = get_long_name(1);
   if (!name.is_null()) {
     if (!current_language)
       error("no current hyphenation language");
     else
-      current_language->patterns.read_patterns_file(name.contents());
+      current_language->patterns.read_patterns_file(name.contents(), append);
   }
   skip_line();
 }
 
+static void hyphenation_patterns_file()
+{
+  do_hyphenation_patterns_file(0);
+}
+
+static void hyphenation_patterns_file_append()
+{
+  do_hyphenation_patterns_file(1);
+}
+
 class hyphenation_language_reg : public reg {
 public:
   const char *get_string();
@@ -3547,5 +3558,6 @@ void init_hyphen_requests()
   init_request("hw", hyphen_word);
   init_request("hla", set_hyphenation_language);
   init_request("hpf", hyphenation_patterns_file);
+  init_request("hpfa", hyphenation_patterns_file_append);
   number_reg_dictionary.define(".hla", new hyphenation_language_reg);
 }