Usage after database close

[Floris Bruynooghe]

Hi,

I started writing some test cases to define better what you can do with
a closed database and make sure that the python bindings do not behave
unexpectedly here too.

One of the first things I tried ends up with xapian calling
exit_group(2) directly, terminating the process.  So I'm wondering if
I'm approaching this entirely the wrong way.  My understanding is that
we should generally be allowed to use anything after the database has
been closed, as long as nothing has been destroyed.

Below is a minimal reproducible example of what I'm testing so far.  I
must admit I'm generally lazy here and usually just test with notmuch
that is currently in Debian testing.

Cheers,
Floris

Here the script:

#!/bin/sh

MAILDIR=$(mktemp --directory)
export MAILDIR
echo $MAILDIR

mkdir $MAILDIR/tmp
mkdir $MAILDIR/new
mkdir $MAILDIR/cur

cat > $MAILDIR/notmuch-config <<EOF
[database]
path=$MAILDIR
[user]
name=Some Hacker
primary_email=dst at example.com
[new]
tags=unread;inbox;
ignore=
[search]
exclude_tags=deleted;spam;
[maildir]
synchronize_flags=true
EOF

NOTMUCH_CONFIG=$MAILDIR/notmuch-config
export NOTMUCH_CONFIG

cat > $MAILDIR/cur/1593342032.M818430P304029Q3.powell <<EOF
Received: by MailDir; Sun Jun 28 13:00:32 2020
Message-ID: <0 at powell.devork.be>
Date: Sun, 28 Jun 2020 13:00:32 -0000
From: src at example.com
To: dst at example.com
Subject: Test mail
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0

This is a test mail
EOF

notmuch new

cat >$MAILDIR/test.c <<EOF
#include <stdio.h>
#include <notmuch.h>

int main(int argc, char** argv) {
    notmuch_status_t status;
    notmuch_database_t* db;
    notmuch_message_t* msg;
    const char* messageid;
    printf("Opening db\n");
    status = notmuch_database_open(argv[1], NOTMUCH_DATABASE_MODE_READ_ONLY, &db);
    if (status != NOTMUCH_STATUS_SUCCESS) {
        return status;
    }
    printf("Finding msg\n");
    status = notmuch_database_find_message(db, "0 at powell.devork.be", &msg);
    if (status != NOTMUCH_STATUS_SUCCESS) {
        return status;
    }
    printf("Closing db\n");
    status = notmuch_database_close(db);
    if (status != NOTMUCH_STATUS_SUCCESS) {
        return status;
    }
    printf("Get messageid\n");
    messageid = notmuch_message_get_message_id(msg);
    if (messageid == NULL) {
        return 1;
    }
    printf("Messageid: %s\n", messageid);
    printf("The end.\n");
}
EOF

gcc $MAILDIR/test.c -lnotmuch -o $MAILDIR/test

$MAILDIR/test $MAILDIR