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+From: Daniel Kahn Gillmor <dkg@fifthhorseman.net>\r
+To: Notmuch Mail <notmuch@notmuchmail.org>\r
+Subject: [PATCH 2/2] fix thread breakage via ghost-on-removal\r
+Date: Fri, 1 Apr 2016 20:31:55 -0300\r
+Message-Id: <1459553515-18802-2-git-send-email-dkg@fifthhorseman.net>\r
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+References: <1459445693-3900-1-git-send-email-dkg@fifthhorseman.net>\r
+ <1459553515-18802-1-git-send-email-dkg@fifthhorseman.net>\r
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+\r
+This is the solution to T590-thread-breakage.sh that just adds a ghost\r
+message after removing each message.\r
+\r
+It leaks information about whether we've ever seen a given message id,\r
+but it's a fairly simple implementation.\r
+\r
+Note that _resolve_message_id_to_thread_id also introduces new\r
+message_ids to the database, so i think just searching for a given\r
+message ID may introduce the same metadata leakage.\r
+---\r
+ lib/database.cc | 28 ++++++++++++++++++++++++++--\r
+ 1 file changed, 26 insertions(+), 2 deletions(-)\r
+\r
+diff --git a/lib/database.cc b/lib/database.cc\r
+index 3b342f1..6c9e34a 100644\r
+--- a/lib/database.cc\r
++++ b/lib/database.cc\r
+@@ -2557,9 +2557,33 @@ notmuch_database_remove_message (notmuch_database_t *notmuch,\r
+ \r
+ if (status == NOTMUCH_STATUS_SUCCESS && message) {\r
+ status = _notmuch_message_remove_filename (message, filename);\r
+- if (status == NOTMUCH_STATUS_SUCCESS)\r
++ if (status == NOTMUCH_STATUS_SUCCESS) {\r
++ const char *mid, *tid;\r
++ notmuch_message_t *ghost;\r
++ notmuch_private_status_t private_status;\r
++ \r
++ mid = notmuch_message_get_message_id (message);\r
++ tid = notmuch_message_get_thread_id (message);\r
++ /* remove the message */\r
+ _notmuch_message_delete (message);\r
+- else if (status == NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID)\r
++ \r
++ /* and reintroduce a ghost in its place */\r
++ ghost = _notmuch_message_create_for_message_id (notmuch, mid, &private_status);\r
++ if (private_status == NOTMUCH_PRIVATE_STATUS_SUCCESS) {\r
++ /* this is deeply weird, and we should not have\r
++ gotten into this state. is there a better\r
++ error message to return here? */\r
++ status = NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID;\r
++ } else if (private_status == NOTMUCH_PRIVATE_STATUS_NO_DOCUMENT_FOUND) {\r
++ private_status = _notmuch_message_initialize_ghost (ghost, tid);\r
++ if (! private_status) {\r
++ _notmuch_message_sync (ghost);\r
++ notmuch_message_destroy (ghost);\r
++ }\r
++ }\r
++ \r
++ status = COERCE_STATUS (private_status, "Error converting to ghost message");\r
++ } else if (status == NOTMUCH_STATUS_DUPLICATE_MESSAGE_ID)\r
+ _notmuch_message_sync (message);\r
+ \r
+ notmuch_message_destroy (message);\r
+-- \r
+2.8.0.rc3\r
+\r