From: Michal Sojka <sojkam1@fel.cvut.cz>
To: notmuch@notmuchmail.org
Date: Thu, 18 Mar 2010 16:39:39 +0100
Message-Id: <1268926780-20045-4-git-send-email-sojkam1@fel.cvut.cz>
In-Reply-To: <1268926780-20045-1-git-send-email-sojkam1@fel.cvut.cz>
References: <1268926780-20045-1-git-send-email-sojkam1@fel.cvut.cz>
Subject: [notmuch] [PATCH 3/4] Add maildir-based mailstore
Precedence: list

This mailstore allows bi-directional synchronization between maildir
flags and certain tags. The flag-to-tag mapping is defined by flag2tag
array.

The synchronization works this way:

1) Whenever notmuch new is executed, then for every new/renamed
   message the tags defined in flag2tag are either added or removed
   depending on the flags from the file name.

2) Whenever notmuch tag is executed, a new set of flags based on the
   tags is constructed and if the new flags differ from that stored in
   the file name, the file is renamed and notmuch database is updated
   to contain the new name for the file.

This mailstore is enabled by putting
    [mailstore]
    type=maildir
to your .notmuch-config.

Signed-off-by: Michal Sojka <sojkam1@fel.cvut.cz>
---
 lib/database.cc       |    7 ++
 lib/mailstore-files.c |  167 ++++++++++++++++++++++++++++++++++++++++++++++++-
 lib/mailstore.c       |    1 +
 lib/message.cc        |   41 ++++++++++++-
 lib/notmuch-private.h |    4 +
 lib/notmuch.h         |    1 +
 6 files changed, 217 insertions(+), 4 deletions(-)

diff --git a/lib/database.cc b/lib/database.cc
index 93c8d0f..33ef889 100644
--- a/lib/database.cc
+++ b/lib/database.cc
@@ -1471,6 +1471,13 @@ notmuch_database_add_message (notmuch_database_t *notmuch,
 
 	_notmuch_message_add_filename (message, filename);
 
+	/* This is a new message or it has a new filename and as such,
+	 * its tags in database either do not exists or might be out
+	 * of date. Mailstore assigns the tags later in index_new(),
+	 * but until then we should not synchronize the tags back to
+	 * the mailstore. */
+	notmuch_message_set_flag(message, NOTMUCH_MESSAGE_FLAG_TAGS_INVALID, TRUE);
+
 	/* Is this a newly created message object? */
 	if (private_status == NOTMUCH_PRIVATE_STATUS_NO_DOCUMENT_FOUND) {
 	    _notmuch_message_add_term (message, "type", "mail");
diff --git a/lib/mailstore-files.c b/lib/mailstore-files.c
index ace2664..d89e183 100644
--- a/lib/mailstore-files.c
+++ b/lib/mailstore-files.c
@@ -24,6 +24,9 @@
 #include "notmuch.h"
 #include "mailstore-private.h"
 #include <dirent.h>
+#include <stdbool.h>
+
+#define ARRAY_SIZE(arr) (sizeof (arr) / sizeof (arr[0]))
 
 typedef struct _filename_node {
     char *filename;
@@ -69,8 +72,9 @@ _filename_list_add (_filename_list_t *list,
 }
 
 static void
-tag_inbox_and_unread (notmuch_message_t *message)
+tag_inbox_and_unread (notmuch_message_t *message, const char *filename)
 {
+    (void)filename;
     notmuch_message_add_tag (message, "inbox");
     notmuch_message_add_tag (message, "unread");
 }
@@ -117,6 +121,141 @@ _entries_resemble_maildir (struct dirent **entries, int count)
 }
 
 
+struct mailstore_priv {
+    void (*tag_new)(notmuch_message_t *message, const char *filename);
+    void (*tag_renamed)(notmuch_message_t *message, const char *filename);
+};
+
+struct maildir_flag_tag {
+    char flag;
+    const char *tag;
+    bool inverse;
+};
+
+/* ASCII ordered table of Maildir flags and assiciated tags */
+struct maildir_flag_tag flag2tag[] = {
+    { 'D', "draft",   false},
+    { 'F', "flagged", false},
+    { 'P', "passed",  false},
+    { 'R', "replied", false},
+    { 'S', "unread",  true },
+    { 'T', "delete",  false},
+};
+
+static void
+tag_from_maildir_flags(notmuch_message_t *message, const char *filename)
+{
+    const char *flags, *p;
+    char f;
+    bool valid, unread;
+    unsigned i;
+
+    flags = strstr(filename, ":2,");
+    if (!flags)
+	return;
+    flags += 3;
+
+    /*  Check that the letters are valid Maildir flags */
+    f = 0;
+    valid = true;
+    for (p=flags; valid && *p; p++) {
+	switch (*p) {
+	case 'P':
+	case 'R':
+	case 'S':
+	case 'T':
+	case 'D':
+	case 'F':
+	    if (*p > f) f=*p;
+	    else valid = false;
+	break;
+	default:
+	    valid = false;
+	}
+    }
+    if (!valid) {
+	/* fprintf(stderr, "Note: Invalid maildir flags: %s\n", message->filename); */
+	return;
+    }
+
+    notmuch_message_freeze(message);
+    unread = true;
+    for (i = 0; i < ARRAY_SIZE(flag2tag); i++) {
+	if ((strchr(flags, flag2tag[i].flag) != NULL) ^ flag2tag[i].inverse) {
+	    notmuch_message_add_tag (message, flag2tag[i].tag);
+	} else {
+	    notmuch_message_remove_tag (message, flag2tag[i].tag);
+	}
+    }
+    notmuch_message_thaw(message);
+
+    /* From now on, we can synchronize the tags from the database to
+     * the mailstore. */
+    notmuch_message_set_flag(message, NOTMUCH_MESSAGE_FLAG_TAGS_INVALID, FALSE);
+}
+
+/* Store maildir-related tags as maildir flags */
+static notmuch_private_status_t
+maildir_sync_tags(notmuch_mailstore_t *mailstore,
+		  notmuch_message_t *message)
+{
+    notmuch_tags_t *tags;
+    const char *tag;
+    char flags[ARRAY_SIZE(flag2tag)+1];
+    unsigned i;
+    char *p;
+    const char *filename;
+    char *filename_new;
+
+    (void)mailstore;
+    for (i = 0; i < ARRAY_SIZE(flag2tag); i++)
+	flags[i] = flag2tag[i].inverse ? flag2tag[i].flag : '\0';
+
+    for (tags = notmuch_message_get_tags (message);
+	 notmuch_tags_valid (tags);
+	 notmuch_tags_move_to_next (tags))
+    {
+	tag = notmuch_tags_get (tags);
+	for (i = 0; i < ARRAY_SIZE(flag2tag); i++) {
+	    if (strcmp(tag, flag2tag[i].tag) == 0)
+		flags[i] = flag2tag[i].inverse ? '\0' : flag2tag[i].flag;
+	}
+    }
+
+    p = flags;
+    for (i = 0; i < ARRAY_SIZE(flag2tag); i++) {
+	if (flags[i])
+	    *p++ = flags[i];
+    }
+    *p = '\0';
+
+    filename = notmuch_message_get_filename(message);
+    p = strstr(filename, ":2,");
+    if (!p)
+	return NOTMUCH_STATUS_SUCCESS; /* FIXME: Is this OK?  */
+    p += 3;
+    filename_new = talloc_size(message, (p-filename) + sizeof(flags));
+    if (unlikely (filename_new == NULL))
+	return NOTMUCH_STATUS_OUT_OF_MEMORY;
+    memcpy(filename_new, filename, p-filename);
+    strcpy(filename_new+(p-filename), flags);
+
+    if (strcmp (filename, filename_new) != 0) {
+	rename (filename, filename_new);
+
+	return _notmuch_message_rename (message, filename_new);
+	/* _notmuch_message_sync is our caller. Do not call it here. */
+    }
+    return NOTMUCH_STATUS_SUCCESS;
+}
+
+static void
+tag_inbox_and_maildir_flags (notmuch_message_t *message, const char *filename)
+{
+    notmuch_message_add_tag (message, "inbox");
+    tag_from_maildir_flags(message, filename);
+}
+
 /* Examine 'path' recursively as follows:
  *
  *   o Ask the filesystem for the mtime of 'path' (fs_mtime)
@@ -171,6 +310,7 @@ add_files_recursive (notmuch_mailstore_t *mailstore,
     struct stat st;
     notmuch_bool_t is_maildir, new_directory;
     _indexing_context_priv_t *priv = state->priv;
+    struct mailstore_priv *mailstore_priv = mailstore->priv;
     notmuch_database_t *notmuch = mailstore->notmuch;
 
     if (stat (path, &st)) {
@@ -362,11 +502,12 @@ add_files_recursive (notmuch_mailstore_t *mailstore,
 	/* success */
 	case NOTMUCH_STATUS_SUCCESS:
 	    state->added_messages++;
-	    tag_inbox_and_unread (message);
+	    mailstore_priv->tag_new (message, next);
 	    break;
 	/* Non-fatal issues (go on to next file) */
 	case NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID:
-	    /* Stay silent on this one. */
+	    if (mailstore_priv->tag_renamed)
+		mailstore_priv->tag_renamed (message, next);
 	    break;
 	case NOTMUCH_STATUS_FILE_NOT_EMAIL:
 	    fprintf (stderr, "Note: Ignoring non-mail file: %s\n",
@@ -623,6 +764,10 @@ open_file(notmuch_mailstore_t *mailstore, const char *filename)
     return fopen (abs_filename, "r");
 }
 
+struct mailstore_priv files_priv = {
+    .tag_new = tag_inbox_and_unread,
+};
+
 /* Original notmuch mail store */
 struct _notmuch_mailstore mailstore_files = {
     .type = "files",
@@ -630,4 +775,20 @@ struct _notmuch_mailstore mailstore_files = {
     .index_new = index_new,
     .sync_tags = NULL,
     .open_file = open_file,
+    .priv = &files_priv,
+};
+
+struct mailstore_priv maildir_priv = {
+    .tag_new = tag_inbox_and_maildir_flags,
+    .tag_renamed = tag_from_maildir_flags,
+};
+
+/* Similar to mailstore_files, but does bi-directional synchronization between certain tags and maildir flags */
+struct _notmuch_mailstore mailstore_maildir = {
+    .type = "maildir",
+    .count_files = count_files,
+    .index_new = index_new,
+    .sync_tags = maildir_sync_tags,
+    .open_file = open_file,
+    .priv = &maildir_priv,
 };
diff --git a/lib/mailstore.c b/lib/mailstore.c
index cdac9a6..7dc55ad 100644
--- a/lib/mailstore.c
+++ b/lib/mailstore.c
@@ -25,6 +25,7 @@
 
 static notmuch_mailstore_t *available[] = {
     &mailstore_files,
+    &mailstore_maildir,
 };
 
 notmuch_mailstore_t *
diff --git a/lib/message.cc b/lib/message.cc
index c32ee7d..51208ba 100644
--- a/lib/message.cc
+++ b/lib/message.cc
@@ -561,7 +561,8 @@ _notmuch_message_sync (notmuch_message_t *message)
     if (message->notmuch->mode == NOTMUCH_DATABASE_MODE_READ_ONLY)
 	return;
 
-    if (message->notmuch->mailstore->sync_tags) {
+    if (message->notmuch->mailstore->sync_tags &&
+	!notmuch_message_get_flag(message, NOTMUCH_MESSAGE_FLAG_TAGS_INVALID)) {
 	status = message->notmuch->mailstore->sync_tags (message->notmuch->mailstore,
 							 message);
 	if (status != NOTMUCH_PRIVATE_STATUS_SUCCESS) {
@@ -683,6 +684,44 @@ _notmuch_message_remove_term (notmuch_message_t *message,
     return NOTMUCH_PRIVATE_STATUS_SUCCESS;
 }
 
+/* Change the message filename stored in the database.
+ *
+ * This change will not be reflected in the database until the next
+ * call to _notmuch_message_sync.
+ */
+notmuch_private_status_t
+_notmuch_message_rename (notmuch_message_t *message,
+			 const char *new_filename)
+{
+    void *local = talloc_new (message);
+    char *direntry;
+    Xapian::PostingIterator i, end;
+    Xapian::Document document;
+    notmuch_private_status_t pstatus;
+    notmuch_status_t status;
+    const char *old_filename;
+
+    old_filename = notmuch_message_get_filename(message);
+    old_filename = talloc_reference(local, old_filename);
+    if (unlikely(!old_filename))
+	return NOTMUCH_PRIVATE_STATUS_OUT_OF_MEMORY;
+
+    status = _notmuch_message_add_filename (message, new_filename);
+    if (status)
+	return (notmuch_private_status_t)status;
+
+    status = _notmuch_database_filename_to_direntry (local, message->notmuch,
+						     old_filename, &direntry);
+    if (status)
+	return (notmuch_private_status_t)status;
+
+    pstatus = _notmuch_message_remove_term (message, "file-direntry", direntry);
+
+    talloc_free (local);
+
+    return pstatus;
+}
+
 notmuch_status_t
 notmuch_message_add_tag (notmuch_message_t *message, const char *tag)
 {
diff --git a/lib/notmuch-private.h b/lib/notmuch-private.h
index d52d84d..63e75ec 100644
--- a/lib/notmuch-private.h
+++ b/lib/notmuch-private.h
@@ -245,6 +245,10 @@ notmuch_status_t
 _notmuch_message_add_filename (notmuch_message_t *message,
 			       const char *filename);
 
+notmuch_private_status_t
+_notmuch_message_rename (notmuch_message_t *message,
+			 const char *new_filename);
+
 void
 _notmuch_message_ensure_thread_id (notmuch_message_t *message);
 
diff --git a/lib/notmuch.h b/lib/notmuch.h
index 4f4cc8b..eab909b 100644
--- a/lib/notmuch.h
+++ b/lib/notmuch.h
@@ -761,6 +761,7 @@ notmuch_message_get_filename (notmuch_message_t *message);
 /* Message flags */
 typedef enum _notmuch_message_flag {
     NOTMUCH_MESSAGE_FLAG_MATCH,
+    NOTMUCH_MESSAGE_FLAG_TAGS_INVALID,
 } notmuch_message_flag_t;
 
 /* Get a value of a flag for the email corresponding to 'message'. */
-- 
1.7.0