Move terms and tags code to a new tags.cc file.

We want to start using this from both message.cc and thread.cc so we
need it in a place we can share the code. This also requires a new
notmuch-private-cxx.h header file for interfaces that include
C++-specific datatypes (such as Xapian::Document).

Makefile

@@ -18,6 +18,7 @@ MODULES=		\
 	message-file.o	\
 	query.o		\
 	sha1.o		\
+	tags.o		\
 	thread.o	\
 	libsha1.o	\
 	xutil.o

message.cc

@@ -18,7 +18,7 @@
  * Author: Carl Worth <cworth@cworth.org>
  */
 
-#include "notmuch-private.h"
+#include "notmuch-private-cxx.h"
 #include "database-private.h"
 
 #include <xapian.h>
@@ -32,15 +32,6 @@ struct _notmuch_message {
     Xapian::Document doc;
 };
 
-typedef struct _notmuch_terms {
-    char prefix_char;
-    Xapian::TermIterator iterator;
-    Xapian::TermIterator iterator_end;
-} notmuch_terms_t;
-
-struct _notmuch_tags {
-    notmuch_terms_t terms;
-};
 
 /* "128 bits of thread-id ought to be enough for anybody" */
 #define NOTMUCH_THREAD_ID_BITS	 128
@@ -295,59 +286,6 @@ notmuch_message_get_filename (notmuch_message_t *message)
     return message->filename;
 }
 
-/* We end up having to call the destructors explicitly because we had
- * to use "placement new" in order to initialize C++ objects within a
- * block that we allocated with talloc. So C++ is making talloc
- * slightly less simple to use, (we wouldn't need
- * talloc_set_destructor at all otherwise).
- */
-static int
-_notmuch_terms_destructor (notmuch_terms_t *terms)
-{
-    terms->iterator.~TermIterator ();
-    terms->iterator_end.~TermIterator ();
-
-    return 0;
-}
-
-static notmuch_terms_t *
-_notmuch_terms_create (void *ctx,
-		       Xapian::Document doc,
-		       const char *prefix_name)
-{
-    notmuch_terms_t *terms;
-    const char *prefix = _find_prefix (prefix_name);
-
-    /* Currently, notmuch_terms_t is written with the assumption that
-     * any prefix its derivatives use will be only a single
-     * character. */
-    assert (strlen (prefix) == 1);
-
-    terms = talloc (ctx, notmuch_terms_t);
-    if (unlikely (terms == NULL))
-	return NULL;
-
-    terms->prefix_char = *prefix;
-    new (&terms->iterator) Xapian::TermIterator;
-    new (&terms->iterator_end) Xapian::TermIterator;
-
-    talloc_set_destructor (terms, _notmuch_terms_destructor);
-
-    terms->iterator = doc.termlist_begin ();
-    terms->iterator.skip_to (prefix);
-    terms->iterator_end = doc.termlist_end ();
-
-    return terms;
-}
-
-/* The assertion is to ensure that 'type' is a derivative of
- * notmuch_terms_t in that it contains a notmuch_terms_t as its first
- * member. We do this by name of 'terms' as opposed to type, because
- * that's as clever as I've been so far. */
-#define _notmuch_terms_create_type(ctx, doc, prefix_name, type) \
-    (COMPILE_TIME_ASSERT(offsetof(type, terms) == 0),		\
-     (type *) _notmuch_terms_create (ctx, doc, prefix_name))
-
 notmuch_tags_t *
 notmuch_message_get_tags (notmuch_message_t *message)
 {
@@ -525,60 +463,3 @@ notmuch_message_destroy (notmuch_message_t *message)
 {
     talloc_free (message);
 }
-
-static notmuch_bool_t
-_notmuch_terms_has_more (notmuch_terms_t *terms)
-{
-    std::string s;
-
-    if (terms->iterator == terms->iterator_end)
-	return FALSE;
-
-    s = *terms->iterator;
-    if (! s.empty () && s[0] == terms->prefix_char)
-	return TRUE;
-    else
-	return FALSE;
-}
-
-static const char *
-_notmuch_terms_get (notmuch_terms_t *terms)
-{
-    return talloc_strdup (terms, (*terms->iterator).c_str () + 1);
-}
-
-static void
-_notmuch_terms_advance (notmuch_terms_t *terms)
-{
-    terms->iterator++;
-}
-
-static void
-_notmuch_terms_destroy (notmuch_terms_t *terms)
-{
-    talloc_free (terms);
-}
-
-notmuch_bool_t
-notmuch_tags_has_more (notmuch_tags_t *tags)
-{
-    return _notmuch_terms_has_more (&tags->terms);
-}
-
-const char *
-notmuch_tags_get (notmuch_tags_t *tags)
-{
-    return _notmuch_terms_get (&tags->terms);
-}
-
-void
-notmuch_tags_advance (notmuch_tags_t *tags)
-{
-    return _notmuch_terms_advance (&tags->terms);
-}
-
-void
-notmuch_tags_destroy (notmuch_tags_t *tags)
-{
-    return _notmuch_terms_destroy (&tags->terms);
-}

notmuch-private-cxx.h

@@ -0,0 +1,60 @@
+/* notmuch-private-cxx.h - Internal, C++ interfaces for notmuch.
+ *
+ * Copyright © 2009 Carl Worth
+ *
+ * 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 3 of the License, 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, see http://www.gnu.org/licenses/ .
+ *
+ * Author: Carl Worth <cworth@cworth.org>
+ */
+
+#ifndef NOTMUCH_PRIVATE_CXX_H
+#define NOTMUCH_PRIVATE_CXX_H
+
+/* It's a bit annoying to have a separate C++ private header, but I
+ * don't yet have C wrappers for types like Xapian::Document and
+ * Xapian::PostingIterator. Maybe I'll write those to be able to fold
+ * this stuff back into notmuch-private.h */
+
+#include "notmuch-private.h"
+
+#include <xapian.h>
+
+/***********/
+/* tags.cc */
+/***********/
+
+typedef struct _notmuch_terms {
+    char prefix_char;
+    Xapian::TermIterator iterator;
+    Xapian::TermIterator iterator_end;
+} notmuch_terms_t;
+
+struct _notmuch_tags {
+    notmuch_terms_t terms;
+};
+
+notmuch_terms_t *
+_notmuch_terms_create (void *ctx,
+		       Xapian::Document doc,
+		       const char *prefix_name);
+
+/* The assertion is to ensure that 'type' is a derivative of
+ * notmuch_terms_t in that it contains a notmuch_terms_t as its first
+ * member. We do this by name of 'terms' as opposed to type, because
+ * that's as clever as I've been so far. */
+#define _notmuch_terms_create_type(ctx, doc, prefix_name, type) \
+    (COMPILE_TIME_ASSERT(offsetof(type, terms) == 0),		\
+     (type *) _notmuch_terms_create (ctx, doc, prefix_name))
+
+#endif

tags.cc

@@ -0,0 +1,126 @@
+/* tags.cc - Iterator for tags returned from message or thread
+ *
+ * Copyright © 2009 Carl Worth
+ *
+ * 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 3 of the License, 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, see http://www.gnu.org/licenses/ .
+ *
+ * Author: Carl Worth <cworth@cworth.org>
+ */
+
+#include "notmuch-private-cxx.h"
+#include "database-private.h"
+
+#include <xapian.h>
+
+/* We end up having to call the destructors explicitly because we had
+ * to use "placement new" in order to initialize C++ objects within a
+ * block that we allocated with talloc. So C++ is making talloc
+ * slightly less simple to use, (we wouldn't need
+ * talloc_set_destructor at all otherwise).
+ */
+static int
+_notmuch_terms_destructor (notmuch_terms_t *terms)
+{
+    terms->iterator.~TermIterator ();
+    terms->iterator_end.~TermIterator ();
+
+    return 0;
+}
+
+notmuch_terms_t *
+_notmuch_terms_create (void *ctx,
+		       Xapian::Document doc,
+		       const char *prefix_name)
+{
+    notmuch_terms_t *terms;
+    const char *prefix = _find_prefix (prefix_name);
+
+    /* Currently, notmuch_terms_t is written with the assumption that
+     * any prefix its derivatives use will be only a single
+     * character. */
+    assert (strlen (prefix) == 1);
+
+    terms = talloc (ctx, notmuch_terms_t);
+    if (unlikely (terms == NULL))
+	return NULL;
+
+    terms->prefix_char = *prefix;
+    new (&terms->iterator) Xapian::TermIterator;
+    new (&terms->iterator_end) Xapian::TermIterator;
+
+    talloc_set_destructor (terms, _notmuch_terms_destructor);
+
+    terms->iterator = doc.termlist_begin ();
+    terms->iterator.skip_to (prefix);
+    terms->iterator_end = doc.termlist_end ();
+
+    return terms;
+}
+
+static notmuch_bool_t
+_notmuch_terms_has_more (notmuch_terms_t *terms)
+{
+    std::string s;
+
+    if (terms->iterator == terms->iterator_end)
+	return FALSE;
+
+    s = *terms->iterator;
+    if (! s.empty () && s[0] == terms->prefix_char)
+	return TRUE;
+    else
+	return FALSE;
+}
+
+static const char *
+_notmuch_terms_get (notmuch_terms_t *terms)
+{
+    return talloc_strdup (terms, (*terms->iterator).c_str () + 1);
+}
+
+static void
+_notmuch_terms_advance (notmuch_terms_t *terms)
+{
+    terms->iterator++;
+}
+
+static void
+_notmuch_terms_destroy (notmuch_terms_t *terms)
+{
+    talloc_free (terms);
+}
+
+notmuch_bool_t
+notmuch_tags_has_more (notmuch_tags_t *tags)
+{
+    return _notmuch_terms_has_more (&tags->terms);
+}
+
+const char *
+notmuch_tags_get (notmuch_tags_t *tags)
+{
+    return _notmuch_terms_get (&tags->terms);
+}
+
+void
+notmuch_tags_advance (notmuch_tags_t *tags)
+{
+    return _notmuch_terms_advance (&tags->terms);
+}
+
+void
+notmuch_tags_destroy (notmuch_tags_t *tags)
+{
+    return _notmuch_terms_destroy (&tags->terms);
+}