Introduce an alternative callback function calling convention.

Depending on the tree-api option to the GRECS_SETUP macro,
the signature of callback functions changes.  If the option
is supplied, a pointer to grecs_node_t is passwd to callback
functions as an argument instead of pointers to the value and
locus.

* am/grecs.m4 (GRECS_SETUP): New option tree-api.
* src/.gitignore: Add grecs.h
* src/Make.am: Build grecs.h
* src/grecs.h: Rename to src/grecs.hin
(GRECS_TREE_API): New define
(grecs_callback_fn): Provide two alternative
signatures depending on the value of GRECS_TREE_API.
All uses updated.
* src/tree.c (fake_callback): Update signature.
(grecs_process_ident)
(stmt_begin,stmt_end): Update calls to callback.
* tests/gcfset.c: Likewise.

7 files changed, 94 insertions, 21 deletions

diff --git a/am/grecs.m4 b/am/grecs.m4
index 36ecf8f..2787563 100644
--- a/am/grecs.m4
+++ b/am/grecs.m4
@@ -65,6 +65,9 @@ AC_DEFUN([_GRECS_SET_OPTIONS],
 #   shared             Build shared (convenience) library.
 #   install-headers    [with "shared"] Install Grecs headers to
 #                      GRECS_INCLUDE_DIR.
+#   tree-api           Use alternative signature of callback functions,
+#                      passing a pointer to grecs_node_t as an argument,
+#                      instead of pointers to the value and locus.
 #
 # The pp-setup-file argument supplies the pathname of the preprocessor
 # setup file in the source tree.  It is ignored if std-pp-setup option is
@@ -171,7 +174,10 @@ AC_DEFUN([GRECS_SETUP],[
 				      [false]))
   AM_CONDITIONAL([GRECS_COND_INSTALLHEADERS],
                  _GRECS_IF_OPTION_SET([install-headers],[true],[false]))
-		   
+
+  AC_SUBST([GRECS_TREE_API])
+  _GRECS_IF_OPTION_SET([tree-api],[GRECS_TREE_API=1],[GRECS_TREE_API=0])
+		 
   AC_SUBST([GRECS_SRCDIR],$1)
   AC_SUBST([GRECS_BUILD_AUX])
   AC_SUBST([GRECS_INCLUDES])
diff --git a/src/.gitignore b/src/.gitignore
index 6e859b1..322178c 100644
--- a/src/.gitignore
+++ b/src/.gitignore
@@ -14,6 +14,7 @@ bind-gram.c
 bind-gram.h
 bind-gram.output
 bind-lex.c
+grecs.h
 Make-inst.in
 Make-shared.in
 Make-static.in
diff --git a/src/Make.am b/src/Make.am
index 6482d28..7ded902 100644
--- a/src/Make.am
+++ b/src/Make.am
@@ -71,12 +71,19 @@ noinst_HEADERS = grecs-locus.h
 
 EXTRA_DIST=\
  grecs-gram.h\
+ grecs.hin\
  $(GRECS_EXTRA_BIND)\
  $(GRECS_EXTRA_DHCPD)\
  $(GRECS_EXTRA_META1)\
  $(PP_SETUP_FILE)\
  Make.am Make-inst.am Make-shared.am Make-static.am
 
+BUILT_SOURCES=grecs.h
+
+grecs.h: $(abs_srcdir)/grecs.hin
+	$(AM_V_GEN)sed 's/@''GRECS_TREE_API''@/@GRECS_TREE_API@/g' \
+		$(abs_srcdir)/grecs.hin > grecs.h
+
 AM_CPPFLAGS = \
  -I$(srcdir)\
  -I$(top_srcdir)/@GRECS_SUBDIR@\
diff --git a/src/grecs.h b/src/grecs.hin
index ab9e0a8..e83b855 100644
--- a/src/grecs.h
+++ b/src/grecs.hin
@@ -1,5 +1,5 @@
-/* grecs - Gray's Extensible Configuration System
-   Copyright (C) 2007-2012 Sergey Poznyakoff
+/* grecs - Gray's Extensible Configuration System -*- c -*-
+   Copyright (C) 2007-2013 Sergey Poznyakoff
 
    Grecs is free software; you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by the
@@ -40,6 +40,8 @@
 #define GRECS_VERSION_MAJOR 1
 #define GRECS_VERSION_MINOR 0
 
+#define GRECS_TREE_API @GRECS_TREE_API@
+
 struct grecs_version_info {
 	const char *package;
 	const char *version;
@@ -161,11 +163,18 @@ typedef struct grecs_node {
 } grecs_node_t;
 
 typedef int (*grecs_callback_fn)(
+#if GRECS_TREE_API
+	enum grecs_callback_command cmd,
+	grecs_node_t *     /* node */,
+	void *             /* varptr */,
+	void *             /* cb_data */
+#else
 	enum grecs_callback_command cmd,
 	grecs_locus_t *    /* locus */,
 	void *             /* varptr */,
 	grecs_value_t *    /* value */,
 	void *             /* cb_data */
+#endif
 	);
 
 struct grecs_keyword {
diff --git a/src/tree.c b/src/tree.c
index abf170e..a0f8736 100644
--- a/src/tree.c
+++ b/src/tree.c
@@ -253,11 +253,20 @@ grecs_tree_free(struct grecs_node *node)
 
 
 static int
-fake_callback(enum grecs_callback_command cmd,
-	       grecs_locus_t *locus,
-	       void *varptr,
-	       grecs_value_t *value,
-	       void *cb_data)
+fake_callback(
+#if GRECS_TREE_API
+	enum grecs_callback_command cmd,
+	grecs_node_t *node,
+	void *varptr,
+	void *cb_data
+#else	
+	enum grecs_callback_command cmd,
+	grecs_locus_t *locus,
+	void *varptr,
+	grecs_value_t *value,
+	void *cb_data
+#endif	
+	)
 {
 	return 0;
 }
@@ -692,13 +701,24 @@ grecs_process_ident(struct grecs_keyword *kwp, grecs_value_t *value,
 	
 	target = target_ptr(kwp, (char *) base);
 	
-	if (kwp->callback)
+	if (kwp->callback) {
+#if GRECS_TREE_API
+		struct grecs_node node = { 0 };
+		node.locus = *locus;
+		node.v.value = value;
+		node.ident = (char*) kwp->ident;
+		kwp->callback(grecs_callback_set_value,
+			      &node,
+			      target,
+			      &kwp->callback_data);
+#else
 		kwp->callback(grecs_callback_set_value,
 			      locus,
 			      target,
 			      value,
 			      &kwp->callback_data);
-	else if (kwp->type == grecs_type_void || target == NULL)
+#endif
+	} else if (kwp->type == grecs_type_void || target == NULL)
 		return;
 	else if (!value) {
 		grecs_error(locus, 0, "%s has no value", kwp->ident);
@@ -815,11 +835,18 @@ stmt_begin(struct nodeproc_closure *clos,
 		target = target_ptr(kwp, CURRENT_BASE(clos));
 		clos->cursect = kwp;
 		if (kwp->callback) {
+#if GRECS_TREE_API			
+			if (kwp->callback(grecs_callback_section_begin,
+					  node,
+					  target,
+					  &kwp->callback_data))
+#else
 			if (kwp->callback(grecs_callback_section_begin,
 					  &node->locus,
 					  target,
 					  node->v.value,
 					  &kwp->callback_data))
+#endif
 				clos->cursect = &fake;
 		} else
 			kwp->callback_data = target;
@@ -844,11 +871,18 @@ stmt_end(struct nodeproc_closure *clos, struct grecs_node *node)
 	if (!clos->cursect)
 		abort();
 	if (callback)
+#if GRECS_TREE_API			
+		callback(grecs_callback_section_end,
+			 node,
+			 kwp ? target_ptr(kwp, CURRENT_BASE(clos)) : NULL,
+			 dataptr);
+#else		
 		callback(grecs_callback_section_end,
 			 &node->locus,
 			 kwp ? target_ptr(kwp, CURRENT_BASE(clos)) : NULL,
 			 NULL,
 			 dataptr);
+#endif
 	if (kwp)
 		kwp->callback_data = NULL;
 }
diff --git a/src/wordsplit.c b/src/wordsplit.c
index 4fe8d6f..9047369 100644
--- a/src/wordsplit.c
+++ b/src/wordsplit.c
@@ -437,7 +437,8 @@ coalesce_segment (struct wordsplit *wsp, struct wordsplit_node *node)
     {
       len += wsnode_len (p);
     }
-  len += wsnode_len (p);
+  if (p)
+    len += wsnode_len (p);
   end = p;
 
   buf = malloc (len + 1);
@@ -1578,6 +1579,7 @@ wordsplit_perror (struct wordsplit *wsp)
 
     case WRDSE_NOSUPP:
       wsp->ws_error (_("command substitution is not yet supported"));
+      break;
 
     case WRDSE_USAGE:
       wsp->ws_error (_("invalid wordsplit usage"));
diff --git a/tests/gcfset.c b/tests/gcfset.c
index bb54876..14b57cb 100644
--- a/tests/gcfset.c
+++ b/tests/gcfset.c
@@ -45,13 +45,30 @@ struct program {
 
 struct grecs_list *proglist;
 
+#if GRECS_TREE_API
+# define GRECS_CB_ARGS \
+	enum grecs_callback_command cmd,\
+	grecs_node_t *node,\
+	void *varptr,\
+	void *cb_data
+# define GRECS_CB_AUTO \
+	grecs_locus_t *locus = &node->locus;\
+	grecs_value_t *value = node->v.value;
+#else
+# define GRECS_CB_ARGS \
+	enum grecs_callback_command cmd,\
+	grecs_locus_t *locus,\
+	void *varptr,\
+	grecs_value_t *value,\
+	void *cb_data
+# define GRECS_CB_AUTO
+#endif
+		
 static int
-cb_logging_facility(enum grecs_callback_command cmd,
-		   grecs_locus_t *locus,
-		   void *varptr,
-		   grecs_value_t *value,
-		   void *cb_data)
+cb_logging_facility(GRECS_CB_ARGS)
 {
+	GRECS_CB_AUTO
+		
 	if (cmd != grecs_callback_set_value) {
 		grecs_error(locus, 0, _("Unexpected block statement"));
 		return 1;
@@ -102,14 +119,11 @@ static struct grecs_keyword program_kwtab[] = {
 };
 
 static int
-cb_program(enum grecs_callback_command cmd,
-	   grecs_locus_t *locus,
-	   void *varptr,
-	   grecs_value_t *value,
-	   void *cb_data)
+cb_program(GRECS_CB_ARGS)
 {
 	struct program *prog;
 	void **pdata = cb_data;
+	GRECS_CB_AUTO
 
 	switch (cmd) {
 	case grecs_callback_section_begin: