Re: [PATCH v4] lib: Simplify close and codify aborting atomic section

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+Date: Thu, 2 Oct 2014 12:41:34 -0700\r
+From: "W. Trevor King" <wking@tremily.us>\r
+To: Austin Clements <aclements@csail.mit.edu>\r
+Subject: Re: [PATCH v4] lib: Simplify close and codify aborting atomic section\r
+Message-ID: <20141002194134.GP3770@odin.tremily.us>\r
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+On Thu, Oct 02, 2014 at 03:19:08PM -0400, Austin Clements wrote:\r
+> This patch simplifies notmuch_database_close to explicitly abort any\r
+> outstanding transaction and then just call Database::close.  This\r
+> works for both read-only and read/write databases, takes care of\r
+> committing changes, unifies the exception handling path, and codifies\r
+> aborting outstanding transactions.\r
+\r
+I don't expect atomic blocks are particularly useful for read-only\r
+connections.  If they aren't, I'd quibble with the =E2=80=9CThis works for\r
+both read-only=E2=80=A6=E2=80=9D wording above.  If they are, I'd drop the =\r
+read/write\r
+check below:\r
+\r
+> +        /* If there's an outstanding transaction, it's unclear if\r
+> +         * closing the Xapian database commits everything up to\r
+> +         * that transaction, or may discard committed (but\r
+> +         * unflushed) transactions.  To be certain, explicitly\r
+> +         * cancel any outstanding transaction before closing. */\r
+> +        if (notmuch->mode =3D=3D NOTMUCH_DATABASE_MODE_READ_WRITE &&\r
+> +            notmuch->atomic_nesting)\r
+> +            (static_cast <Xapian::WritableDatabase *> (notmuch->xapian_db))\r
+> +                ->cancel_transaction ();\r
+\r
+Thats a very minor quibble though, and I'd be glad to see this patch\r
+land as is.\r
+\r
+Cheers,\r
+Trevor\r
+\r
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