Add full-text indexing using the GMime library for parsing.

This is based on the old notmuch-index-message.cc from early in
the history of notmuch, but considerably cleaned up now that
we have some experience with Xapian and know just what we want
to index, (rather than just blindly trying to index exactly
what sup does).

This does slow down notmuch_database_add_message a *lot*, but I've
got some ideas for getting some time back.

Makefile

@@ -2,27 +2,30 @@ PROGS=notmuch
 
 WARN_FLAGS=-Wall -Wextra -Wmissing-declarations -Wwrite-strings -Wswitch-enum
 
-CDEPENDS_FLAGS=`pkg-config --cflags glib-2.0 talloc`
-CXXDEPENDS_FLAGS=`pkg-config --cflags glib-2.0 talloc` `xapian-config --cxxflags`
+CDEPENDS_FLAGS=`pkg-config --cflags glib-2.0 gmime-2.4 talloc`
+CXXDEPENDS_FLAGS=$(CDEPENDS_FLAGS) `xapian-config --cxxflags`
 
 MYCFLAGS=$(WARN_FLAGS) -O0 -g $(CDEPENDS_FLAGS)
 MYCXXFLAGS=$(WARN_FLAGS) -O0 -g $(CXXDEPENDS_FLAGS)
 
-MYLDFLAGS=`pkg-config --libs glib-2.0 talloc` `xapian-config --libs`
+MYLDFLAGS=`pkg-config --libs glib-2.0 gmime-2.4 talloc` `xapian-config --libs`
 
-MODULES=		\
-	notmuch.o	\
+LIBRARY=		\
 	database.o	\
 	date.o		\
+	index.o		\
+	libsha1.o	\
 	message.o	\
 	message-file.o	\
 	query.o		\
 	sha1.o		\
 	tags.o		\
 	thread.o	\
-	libsha1.o	\
 	xutil.o
 
+MAIN=			\
+	notmuch.o
+
 all: $(PROGS)
 
 %.o: %.cc
@@ -31,7 +34,7 @@ all: $(PROGS)
 %.o: %.c
 	$(CC) -c $(CFLAGS) $(MYCFLAGS) $< -o $@
 
-notmuch: $(MODULES)
+notmuch: $(MAIN) $(LIBRARY)
 	$(CC) $(MYLDFLAGS) $^ -o $@
 
 Makefile.dep: *.c *.cc

database-private.h

@@ -29,6 +29,7 @@ struct _notmuch_database {
     char *path;
     Xapian::WritableDatabase *xapian_db;
     Xapian::QueryParser *query_parser;
+    Xapian::TermGenerator *term_gen;
 };
 
 #endif

database.cc

@@ -114,6 +114,13 @@ prefix_t BOOLEAN_PREFIX_EXTERNAL[] = {
     { "id", "Q" }
 };
 
+prefix_t PROBABILISTIC_PREFIX[]= {
+    { "from", "XFROM" },
+    { "to", "XTO" },
+    { "attachment", "XATTACHMENT" },
+    { "subject", "XSUBJECT"}
+};
+
 int
 _internal_error (const char *format, ...)
 {
@@ -141,6 +148,10 @@ _find_prefix (const char *name)
 	if (strcmp (name, BOOLEAN_PREFIX_EXTERNAL[i].name) == 0)
 	    return BOOLEAN_PREFIX_EXTERNAL[i].prefix;
 
+    for (i = 0; i < ARRAY_SIZE (PROBABILISTIC_PREFIX); i++)
+	if (strcmp (name, PROBABILISTIC_PREFIX[i].name) == 0)
+	    return PROBABILISTIC_PREFIX[i].prefix;
+
     INTERNAL_ERROR ("No prefix exists for '%s'\n", name);
 
     return "";
@@ -478,14 +489,24 @@ notmuch_database_open (const char *path)
 	notmuch->xapian_db = new Xapian::WritableDatabase (xapian_path,
 							   Xapian::DB_CREATE_OR_OPEN);
 	notmuch->query_parser = new Xapian::QueryParser;
+	notmuch->term_gen = new Xapian::TermGenerator;
+	notmuch->term_gen->set_stemmer (Xapian::Stem ("english"));
+
 	notmuch->query_parser->set_default_op (Xapian::Query::OP_AND);
 	notmuch->query_parser->set_database (*notmuch->xapian_db);
+	notmuch->query_parser->set_stemmer (Xapian::Stem ("english"));
+	notmuch->query_parser->set_stemming_strategy (Xapian::QueryParser::STEM_SOME);
 
 	for (i = 0; i < ARRAY_SIZE (BOOLEAN_PREFIX_EXTERNAL); i++) {
 	    prefix_t *prefix = &BOOLEAN_PREFIX_EXTERNAL[i];
 	    notmuch->query_parser->add_boolean_prefix (prefix->name,
 						       prefix->prefix);
 	}
+
+	for (i = 0; i < ARRAY_SIZE (PROBABILISTIC_PREFIX); i++) {
+	    prefix_t *prefix = &PROBABILISTIC_PREFIX[i];
+	    notmuch->query_parser->add_prefix (prefix->name, prefix->prefix);
+	}
     } catch (const Xapian::Error &error) {
 	fprintf (stderr, "A Xapian exception occurred: %s\n",
 		 error.get_msg().c_str());
@@ -508,6 +529,7 @@ notmuch_database_close (notmuch_database_t *notmuch)
 {
     notmuch->xapian_db->flush ();
 
+    delete notmuch->term_gen;
     delete notmuch->query_parser;
     delete notmuch->xapian_db;
     talloc_free (notmuch);
@@ -924,9 +946,11 @@ notmuch_database_add_message (notmuch_database_t *notmuch,
 	{
 	    ret = NOTMUCH_STATUS_FILE_NOT_EMAIL;
 	    goto DONE;
-	} else {
-	    _notmuch_message_sync (message);
 	}
+
+	_notmuch_message_index_file (message, filename);
+
+	_notmuch_message_sync (message);
     } catch (const Xapian::Error &error) {
 	fprintf (stderr, "A Xapian exception occurred: %s.\n",
 		 error.get_msg().c_str());

index.cc

@@ -0,0 +1,260 @@
+/*
+ * 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.h"
+
+#include <gmime/gmime.h>
+
+#include <xapian.h>
+
+/* We're finally down to a single (NAME + address) email "mailbox". */
+static void
+_index_address_mailbox (notmuch_message_t *message,
+			const char *prefix_name,
+			InternetAddress *address)
+{
+    InternetAddressMailbox *mailbox = INTERNET_ADDRESS_MAILBOX (address);
+    const char *name, *addr = internet_address_mailbox_get_addr (mailbox);
+    int own_name = 0;
+
+    if (addr)
+	_notmuch_message_gen_terms (message, prefix_name, addr);
+
+    name = internet_address_get_name (address);
+
+    /* In the absence of a name, we'll strip the part before the @
+     * from the address. */
+    if (! name) {
+	const char *at;
+
+	at = strchr (addr, '@');
+	if (at) {
+	    name = strndup (addr, at - addr);
+	    own_name = 1;
+	}
+    }
+
+    if (name)
+	_notmuch_message_gen_terms (message, prefix_name, name);
+}
+
+static void
+_index_address_list (notmuch_message_t *message,
+		     const char *prefix_name,
+		     InternetAddressList *addresses);
+
+/* The outer loop over the InternetAddressList wasn't quite enough.
+ * There can actually be a tree here where a single member of the list
+ * is a "group" containing another list. Recurse please.
+ */
+static void
+_index_address_group (notmuch_message_t *message,
+		      const char *prefix_name,
+		      InternetAddress *address)
+{
+    InternetAddressGroup *group;
+    InternetAddressList *list;
+
+    group = INTERNET_ADDRESS_GROUP (address);
+    list = internet_address_group_get_members (group);
+
+    if (! list)
+	return;
+
+    _index_address_list (message, prefix_name, list);
+}
+
+static void
+_index_address_list (notmuch_message_t *message,
+		     const char *prefix_name,
+		     InternetAddressList *addresses)
+{
+    int i;
+    InternetAddress *address;
+
+    if (addresses == NULL)
+	return;
+
+    for (i = 0; i < internet_address_list_length (addresses); i++) {
+	address = internet_address_list_get_address (addresses, i);
+	if (INTERNET_ADDRESS_IS_MAILBOX (address)) {
+	    _index_address_mailbox (message, prefix_name, address);
+	} else if (INTERNET_ADDRESS_IS_GROUP (address)) {
+	    _index_address_group (message, prefix_name, address);
+	} else {
+	    INTERNAL_ERROR ("GMime InternetAddress is neither a mailbox nor a group.\n");
+	}
+    }
+}
+
+static const char *
+skip_re_in_subject (const char *subject)
+{
+    const char *s = subject;
+
+    if (subject == NULL)
+	return NULL;
+
+    while (*s) {
+	while (*s && isspace (*s))
+	    s++;
+	if (strncasecmp (s, "re:", 3) == 0)
+	    s += 3;
+	else
+	    break;
+    }
+
+    return s;
+}
+
+/* Callback to generate terms for each mime part of a message. */
+static void
+_index_mime_part (notmuch_message_t *message,
+		  GMimeObject *part)
+{
+    GMimeStream *stream;
+    GMimeDataWrapper *wrapper;
+    GByteArray *byte_array;
+    GMimeContentDisposition *disposition;
+    char *body;
+
+    if (GMIME_IS_MULTIPART (part)) {
+	GMimeMultipart *multipart = GMIME_MULTIPART (part);
+	int i;
+
+	for (i = 0; i < g_mime_multipart_get_count (multipart); i++) {
+	    if (GMIME_IS_MULTIPART_SIGNED (multipart)) {
+		/* Don't index the signature. */
+		if (i == 1)
+		    continue;
+		if (i > 1)
+		    fprintf (stderr, "Warning: Unexpected extra parts of mutlipart/signed. Indexing anyway.\n");
+	    }
+	    _index_mime_part (message,
+			      g_mime_multipart_get_part (multipart, i));
+	}
+	return;
+    }
+
+    if (GMIME_IS_MESSAGE_PART (part)) {
+	GMimeMessage *mime_message;
+
+	mime_message = g_mime_message_part_get_message (GMIME_MESSAGE_PART (part));
+
+	_index_mime_part (message, g_mime_message_get_mime_part (mime_message));
+
+	return;
+    }
+
+    if (! (GMIME_IS_PART (part))) {
+	fprintf (stderr, "Warning: Not indexing unknown mime part: %s.\n",
+		 g_type_name (G_OBJECT_TYPE (part)));
+	return;
+    }
+
+    disposition = g_mime_object_get_content_disposition (part);
+    if (disposition &&
+	strcmp (disposition->disposition, GMIME_DISPOSITION_ATTACHMENT) == 0)
+    {
+	const char *filename = g_mime_part_get_filename (GMIME_PART (part));
+
+	_notmuch_message_add_term (message, "tag", "attachment");
+	_notmuch_message_gen_terms (message, "attachment", filename);
+
+	/* XXX: Would be nice to call out to something here to parse
+	 * the attachment into text and then index that. */
+	return;
+    }
+
+    byte_array = g_byte_array_new ();
+
+    stream = g_mime_stream_mem_new_with_byte_array (byte_array);
+    g_mime_stream_mem_set_owner (GMIME_STREAM_MEM (stream), FALSE);
+    wrapper = g_mime_part_get_content_object (GMIME_PART (part));
+    if (wrapper)
+	g_mime_data_wrapper_write_to_stream (wrapper, stream);
+
+    g_object_unref (stream);
+
+    g_byte_array_append (byte_array, (guint8 *) "\0", 1);
+    body = (char *) g_byte_array_free (byte_array, FALSE);
+
+    _notmuch_message_gen_terms (message, NULL, body);
+
+    free (body);
+}
+
+notmuch_status_t
+_notmuch_message_index_file (notmuch_message_t *message,
+			     const char *filename)
+{
+    GMimeStream *stream = NULL;
+    GMimeParser *parser = NULL;
+    GMimeMessage *mime_message = NULL;
+    InternetAddressList *addresses;
+    FILE *file = NULL;
+    const char *from, *subject;
+    notmuch_status_t ret = NOTMUCH_STATUS_SUCCESS;
+    static int initialized = 0;
+
+    if (! initialized) {
+	g_mime_init (0);
+	initialized = 1;
+    }
+
+    file = fopen (filename, "r");
+    if (! file) {
+	fprintf (stderr, "Error opening %s: %s\n", filename, strerror (errno));
+	ret = NOTMUCH_STATUS_FILE_ERROR;
+	goto DONE;
+    }
+
+    /* Evil GMime steals my FILE* here so I won't fclose it. */
+    stream = g_mime_stream_file_new (file);
+
+    parser = g_mime_parser_new_with_stream (stream);
+
+    mime_message = g_mime_parser_construct_message (parser);
+
+    from = g_mime_message_get_sender (mime_message);
+    addresses = internet_address_list_parse_string (from);
+
+    _index_address_list (message, "from", addresses);
+
+    addresses = g_mime_message_get_all_recipients (mime_message);
+    _index_address_list (message, "to", addresses);
+
+    subject = g_mime_message_get_subject (mime_message);
+    subject = skip_re_in_subject (subject);
+    _notmuch_message_gen_terms (message, "subject", subject);
+
+    _index_mime_part (message, g_mime_message_get_mime_part (mime_message));
+
+  DONE:
+    if (mime_message)
+	g_object_unref (mime_message);
+
+    if (parser)
+	g_object_unref (parser);
+
+    if (stream)
+	g_object_unref (stream);
+
+    return ret;
+}

message.cc

@@ -442,6 +442,32 @@ _notmuch_message_add_term (notmuch_message_t *message,
     return NOTMUCH_PRIVATE_STATUS_SUCCESS;
 }
 
+/* Parse 'text' and add a term to 'message' for each parsed word. Each
+ * term will be added both prefixed (if prefix_name is not NULL) and
+ * also unprefixed). */
+notmuch_private_status_t
+_notmuch_message_gen_terms (notmuch_message_t *message,
+			    const char *prefix_name,
+			    const char *text)
+{
+    Xapian::TermGenerator *term_gen = message->notmuch->term_gen;
+
+    if (text == NULL)
+	return NOTMUCH_PRIVATE_STATUS_NULL_POINTER;
+
+    term_gen->set_document (message->doc);
+
+    if (prefix_name) {
+	const char *prefix = _find_prefix (prefix_name);
+
+	term_gen->index_text (text, 1, prefix);
+    }
+
+    term_gen->index_text (text);
+
+    return NOTMUCH_PRIVATE_STATUS_SUCCESS;
+}
+
 /* Remove a name:value term from 'message', (the actual term will be
  * encoded by prefixing the value with a short prefix). See
  * NORMAL_PREFIX and BOOLEAN_PREFIX arrays for the mapping of term

notmuch-private.h

@@ -187,6 +187,11 @@ _notmuch_message_remove_term (notmuch_message_t *message,
 			      const char *prefix_name,
 			      const char *value);
 
+notmuch_private_status_t
+_notmuch_message_gen_terms (notmuch_message_t *message,
+			    const char *prefix_name,
+			    const char *text);
+
 void
 _notmuch_message_set_filename (notmuch_message_t *message,
 			       const char *filename);
@@ -205,6 +210,12 @@ _notmuch_message_set_date (notmuch_message_t *message,
 void
 _notmuch_message_sync (notmuch_message_t *message);
 
+/* index.cc */
+
+notmuch_status_t
+_notmuch_message_index_file (notmuch_message_t *message,
+			     const char *filename);
+
 /* message-file.c */
 
 /* XXX: I haven't decided yet whether these will actually get exported