path: root/modules/spamassassin/evolution-spamassassin.c

/*
 * evolution-spamassassin.c
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) version 3.
 *
 * 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with the program; if not, see <http://www.gnu.org/licenses/>
 *
 */

#include <config.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <glib/gi18n-lib.h>

#include <camel/camel.h>

#include <shell/e-shell.h>
#include <e-util/e-mktemp.h>
#include <e-util/gconf-bridge.h>
#include <mail/e-mail-junk-filter.h>

/* Standard GObject macros */
#define E_TYPE_SPAM_ASSASSIN \
    (e_spam_assassin_get_type ())
#define E_SPAM_ASSASSIN(obj) \
    (G_TYPE_CHECK_INSTANCE_CAST \
    ((obj), E_TYPE_SPAM_ASSASSIN, ESpamAssassin))

#ifndef SPAMASSASSIN_BINARY
#define SPAMASSASSIN_BINARY "/usr/bin/spamassassin"
#endif

#ifndef SA_LEARN_BINARY
#define SA_LEARN_BINARY "/usr/bin/sa-learn"
#endif

#ifndef SPAMC_BINARY
#define SPAMC_BINARY "/usr/bin/spamc"
#endif

#ifndef SPAMD_BINARY
#define SPAMD_BINARY "/usr/bin/spamd"
#endif

/* For starting our own daemon. */
#define DAEMON_MAX_RETRIES 100
#define DAEMON_RETRY_DELAY 0.05  /* seconds */

#define SPAM_ASSASSIN_EXIT_STATUS_SUCCESS   0
#define SPAM_ASSASSIN_EXIT_STATUS_ERROR     -1

typedef struct _ESpamAssassin ESpamAssassin;
typedef struct _ESpamAssassinClass ESpamAssassinClass;

struct _ESpamAssassin {
    EMailJunkFilter parent;

    GMutex *socket_path_mutex;

    gchar *pid_file;
    gchar *socket_path;
    gchar *spamc_binary;
    gchar *spamd_binary;
    gint version;

    gboolean local_only;
    gboolean use_daemon;
    gboolean version_set;

    /* spamc/spamd state */
    gboolean spamd_tested;
    gboolean spamd_using_allow_tell;
    gboolean system_spamd_available;
    gboolean use_spamc;
};

struct _ESpamAssassinClass {
    EMailJunkFilterClass parent_class;
};

enum {
    PROP_0,
    PROP_LOCAL_ONLY,
    PROP_SPAMC_BINARY,
    PROP_SPAMD_BINARY,
    PROP_SOCKET_PATH,
    PROP_USE_DAEMON
};

/* Module Entry Points */
void e_module_load (GTypeModule *type_module);
void e_module_unload (GTypeModule *type_module);

/* Forward Declarations */
GType e_spam_assassin_get_type (void);
static void e_spam_assassin_interface_init (CamelJunkFilterInterface *interface);

G_DEFINE_DYNAMIC_TYPE_EXTENDED (
    ESpamAssassin,
    e_spam_assassin,
    E_TYPE_MAIL_JUNK_FILTER, 0,
    G_IMPLEMENT_INTERFACE_DYNAMIC (
        CAMEL_TYPE_JUNK_FILTER,
        e_spam_assassin_interface_init))

#ifdef G_OS_UNIX
static void
spam_assassin_cancelled_cb (GCancellable *cancellable,
                            GPid *pid)
{
    /* XXX On UNIX-like systems we can safely assume a GPid is the
     *     process ID and use it to terminate the process via signal. */
    kill (*pid, SIGTERM);
}
#endif

static void
spam_assassin_exited_cb (GPid *pid,
                         gint status,
                         gpointer user_data)
{
    struct {
        GMainLoop *loop;
        gint exit_code;
    } *source_data = user_data;

    if (WIFEXITED (status))
        source_data->exit_code = WEXITSTATUS (status);
    else
        source_data->exit_code = SPAM_ASSASSIN_EXIT_STATUS_ERROR;

    g_main_loop_quit (source_data->loop);
}

static gint
spam_assassin_command_full (const gchar **argv,
                            CamelMimeMessage *message,
                            const gchar *input_data,
                            GByteArray *output_buffer,
                            gboolean wait_for_termination,
                            GCancellable *cancellable,
                            GError **error)
{
    GMainContext *context;
    GSpawnFlags flags = 0;
    GSource *source;
    GPid child_pid;
    gint standard_input;
    gint standard_output;
    gulong handler_id = 0;
    gboolean success;

    struct {
        GMainLoop *loop;
        gint exit_code;
    } source_data;

    if (wait_for_termination)
        flags |= G_SPAWN_DO_NOT_REAP_CHILD;
    if (output_buffer == NULL)
        flags |= G_SPAWN_STDOUT_TO_DEV_NULL;
    flags |= G_SPAWN_STDERR_TO_DEV_NULL;

    /* Spawn SpamAssassin with an open stdin pipe. */
    success = g_spawn_async_with_pipes (
        NULL,
        (gchar **) argv,
        NULL,
        flags,
        NULL, NULL,
        &child_pid,
        &standard_input,
        (output_buffer != NULL) ? &standard_output : NULL,
        NULL,
        error);

    if (!success) {
        gchar *command_line;

        command_line = g_strjoinv (" ", (gchar **) argv);
        g_prefix_error (
            error, _("Failed to spawn SpamAssassin (%s): "),
            command_line);
        g_free (command_line);

        return SPAM_ASSASSIN_EXIT_STATUS_ERROR;
    }

    if (message != NULL) {
        CamelStream *stream;
        gssize bytes_written;

        /* Stream the CamelMimeMessage to SpamAssassin. */
        stream = camel_stream_fs_new_with_fd (standard_input);
        bytes_written = camel_data_wrapper_write_to_stream_sync (
            CAMEL_DATA_WRAPPER (message),
            stream, cancellable, error);
        success = (bytes_written >= 0) &&
            (camel_stream_close (stream, cancellable, error) == 0);
        g_object_unref (stream);

        if (!success) {
            g_spawn_close_pid (child_pid);
            g_prefix_error (
                error, _("Failed to stream mail "
                "message content to SpamAssassin: "));
            return SPAM_ASSASSIN_EXIT_STATUS_ERROR;
        }

    } else if (input_data != NULL) {
        gssize bytes_written;

        /* Write raw data directly to SpamAssassin. */
        bytes_written = camel_write (
            standard_input, input_data,
            strlen (input_data), cancellable, error);
        success = (bytes_written >= 0);

        close (standard_input);

        if (!success) {
            g_spawn_close_pid (child_pid);
            g_prefix_error (
                error, _("Failed to write '%s' "
                "to SpamAssassin: "), input_data);
            return SPAM_ASSASSIN_EXIT_STATUS_ERROR;
        }
    }

    if (output_buffer != NULL) {
        CamelStream *input_stream;
        CamelStream *output_stream;
        gssize bytes_written;

        input_stream = camel_stream_fs_new_with_fd (standard_output);

        output_stream = camel_stream_mem_new ();
        camel_stream_mem_set_byte_array (
            CAMEL_STREAM_MEM (output_stream), output_buffer);

        bytes_written = camel_stream_write_to_stream (
            input_stream, output_stream, cancellable, error);
        g_byte_array_append (output_buffer, (guint8 *) "", 1);
        success = (bytes_written >= 0);

        g_object_unref (input_stream);
        g_object_unref (output_stream);

        if (!success) {
            g_spawn_close_pid (child_pid);
            g_prefix_error (
                error, _("Failed to read "
                "output from SpamAssassin: "));
            return SPAM_ASSASSIN_EXIT_STATUS_ERROR;
        }
    }

    /* XXX I'm not sure if we should call g_spawn_close_pid()
     *     here or not.  Only really matters on Windows anyway. */
    if (!wait_for_termination)
        return 0;

    /* Wait for the SpamAssassin process to terminate
     * using GLib's main loop for better portability. */

    context = g_main_context_new ();

    source = g_child_watch_source_new (child_pid);
    g_source_set_callback (
        source, (GSourceFunc)
        spam_assassin_exited_cb,
        &source_data, NULL);
    g_source_attach (source, context);
    g_source_unref (source);

    source_data.loop = g_main_loop_new (context, TRUE);
    source_data.exit_code = 0;

#ifdef G_OS_UNIX
    if (G_IS_CANCELLABLE (cancellable))
        handler_id = g_cancellable_connect (
            cancellable,
            G_CALLBACK (spam_assassin_cancelled_cb),
            &child_pid, (GDestroyNotify) NULL);
#endif

    g_main_loop_run (source_data.loop);

    if (handler_id > 0)
        g_cancellable_disconnect (cancellable, handler_id);

    g_main_loop_unref (source_data.loop);
    source_data.loop = NULL;

    g_main_context_unref (context);

    /* Clean up. */

    g_spawn_close_pid (child_pid);

    if (g_cancellable_set_error_if_cancelled (cancellable, error))
        source_data.exit_code = SPAM_ASSASSIN_EXIT_STATUS_ERROR;

    else if (source_data.exit_code == SPAM_ASSASSIN_EXIT_STATUS_ERROR)
        g_set_error_literal (
            error, CAMEL_ERROR, CAMEL_ERROR_GENERIC,
            _("SpamAssassin either crashed or "
              "failed to process a mail message"));

    return source_data.exit_code;
}

static gint
spam_assassin_command (const gchar **argv,
                       CamelMimeMessage *message,
                       const gchar *input_data,
                       GCancellable *cancellable,
                       GError **error)
{
    return spam_assassin_command_full (
        argv, message, input_data, NULL, TRUE, cancellable, error);
}

static gboolean
spam_assassin_get_local_only (ESpamAssassin *extension)
{
    return extension->local_only;
}

static void
spam_assassin_set_local_only (ESpamAssassin *extension,
                              gboolean local_only)
{
    extension->local_only = local_only;

    g_object_notify (G_OBJECT (extension), "local-only");
}

static const gchar *
spam_assassin_get_spamc_binary (ESpamAssassin *extension)
{
    return extension->spamc_binary;
}

static void
spam_assassin_set_spamc_binary (ESpamAssassin *extension,
                                const gchar *spamc_binary)
{
    g_free (extension->spamc_binary);
    extension->spamc_binary = g_strdup (spamc_binary);

    g_object_notify (G_OBJECT (extension), "spamc-binary");
}

static const gchar *
spam_assassin_get_spamd_binary (ESpamAssassin *extension)
{
    return extension->spamd_binary;
}

static void
spam_assassin_set_spamd_binary (ESpamAssassin *extension,
                                const gchar *spamd_binary)
{
    g_free (extension->spamd_binary);
    extension->spamd_binary = g_strdup (spamd_binary);

    g_object_notify (G_OBJECT (extension), "spamd-binary");
}

static const gchar *
spam_assassin_get_socket_path (ESpamAssassin *extension)
{
    return extension->socket_path;
}

static void
spam_assassin_set_socket_path (ESpamAssassin *extension,
                               const gchar *socket_path)
{
    g_free (extension->socket_path);
    extension->socket_path = g_strdup (socket_path);

    g_object_notify (G_OBJECT (extension), "socket-path");
}

static gboolean
spam_assassin_get_use_daemon (ESpamAssassin *extension)
{
    return extension->use_daemon;
}

static void
spam_assassin_set_use_daemon (ESpamAssassin *extension,
                              gboolean use_daemon)
{
    extension->use_daemon = use_daemon;

    g_object_notify (G_OBJECT (extension), "use-daemon");
}

static gboolean
spam_assassin_get_version (ESpamAssassin *extension,
                           gint *spam_assassin_version,
                           GCancellable *cancellable,
                           GError **error)
{
    GByteArray *output_buffer;
    gint exit_code;
    guint ii;

    const gchar *argv[] = {
        SA_LEARN_BINARY,
        "--version",
        NULL
    };

    if (extension->version_set) {
        if (spam_assassin_version != NULL)
            *spam_assassin_version = extension->version;
        return TRUE;
    }

    output_buffer = g_byte_array_new ();

    exit_code = spam_assassin_command_full (
        argv, NULL, NULL, output_buffer, TRUE, cancellable, error);

    if (exit_code != 0) {
        g_byte_array_free (output_buffer, TRUE);
        return FALSE;
    }

    for (ii = 0; ii < output_buffer->len; ii++) {
        if (g_ascii_isdigit (output_buffer->data[ii])) {
            guint8 ch = output_buffer->data[ii];
            extension->version = (ch - '0');
            extension->version_set = TRUE;
            break;
        }
    }

    if (spam_assassin_version != NULL)
        *spam_assassin_version = extension->version;

    g_byte_array_free (output_buffer, TRUE);

    return TRUE;
}

static void
spam_assassin_test_spamd_allow_tell (ESpamAssassin *extension)
{
    gint exit_code;
    GError *error = NULL;

    const gchar *argv[] = {
        SPAMC_BINARY,
        "--learntype=forget",
        NULL
    };

    /* Check if spamd is running with --allow-tell. */

    exit_code = spam_assassin_command (argv, NULL, "\n", NULL, &error);
    extension->spamd_using_allow_tell = (exit_code == 0);

    if (error != NULL) {
        g_warning ("%s", error->message);
        g_error_free (error);
    }
}

static gboolean
spam_assassin_test_spamd_running (ESpamAssassin *extension,
                                  gboolean system_spamd)
{
    const gchar *argv[5];
    gint exit_code;
    gint ii = 0;
    GError *error = NULL;

    g_mutex_lock (extension->socket_path_mutex);

    argv[ii++] = extension->spamc_binary;
    argv[ii++] = "--no-safe-fallback";
    if (!system_spamd) {
        argv[ii++] = "--socket";
        argv[ii++] = extension->socket_path;
    }
    argv[ii] = NULL;

    g_assert (ii < G_N_ELEMENTS (argv));

    exit_code = spam_assassin_command (
        argv, NULL, "From test@127.0.0.1", NULL, &error);

    if (error != NULL) {
        g_warning ("%s", error->message);
        g_error_free (error);
    }

    g_mutex_unlock (extension->socket_path_mutex);

    return (exit_code == 0);
}

static void
spam_assassin_kill_our_own_daemon (ESpamAssassin *extension)
{
    gint pid;
    gchar *contents = NULL;
    GError *error = NULL;

    g_mutex_lock (extension->socket_path_mutex);

    g_free (extension->socket_path);
    extension->socket_path = NULL;

    g_mutex_unlock (extension->socket_path_mutex);

    if (extension->pid_file == NULL)
        return;

    g_file_get_contents (extension->pid_file, &contents, NULL, &error);

    if (error != NULL) {
        g_warn_if_fail (contents == NULL);
        g_warning ("%s", error->message);
        g_error_free (error);
        return;
    }

    g_return_if_fail (contents != NULL);

    pid = atoi (contents);
    g_free (contents);

    if (pid > 0 && kill (pid, SIGTERM) == 0)
        waitpid (pid, NULL, 0);
}

static void
spam_assassin_prepare_for_quit (EShell *shell,
                                EActivity *activity,
                                ESpamAssassin *extension)
{
    spam_assassin_kill_our_own_daemon (extension);
}

static gboolean
spam_assassin_start_our_own_daemon (ESpamAssassin *extension)
{
    const gchar *argv[8];
    gchar *pid_file;
    gchar *socket_path;
    gboolean started = FALSE;
    gint exit_code;
    gint ii = 0;
    GError *error = NULL;

    g_mutex_lock (extension->socket_path_mutex);

    pid_file = e_mktemp ("spamd-pid-file-XXXXXX");
    socket_path = e_mktemp ("spamd-socket-path-XXXXXX");

    argv[ii++] = extension->spamd_binary;
    argv[ii++] = "--socketpath";
    argv[ii++] = socket_path;

    if (spam_assassin_get_local_only (extension))
        argv[ii++] = "--local";

    argv[ii++] = "--max-children=1";
    argv[ii++] = "--pidfile";
    argv[ii++] = pid_file;
    argv[ii] = NULL;

    g_assert (ii < G_N_ELEMENTS (argv));

    exit_code = spam_assassin_command_full (
        argv, NULL, NULL, NULL, FALSE, NULL, &error);

    if (error != NULL) {
        g_warning ("%s", error->message);
        g_error_free (error);
        goto exit;
    }

    if (exit_code == SPAM_ASSASSIN_EXIT_STATUS_SUCCESS) {
        /* Wait for the socket path to appear. */
        for (ii = 0; ii < DAEMON_MAX_RETRIES; ii++) {
            if (g_file_test (socket_path, G_FILE_TEST_EXISTS)) {
                started = TRUE;
                break;
            }
            g_usleep (DAEMON_RETRY_DELAY * G_USEC_PER_SEC);
        }
    }

    /* Set these directly to avoid emitting "notify" signals. */
    if (started) {
        g_free (extension->pid_file);
        extension->pid_file = pid_file;
        pid_file = NULL;

        g_free (extension->socket_path);
        extension->socket_path = socket_path;
        socket_path = NULL;

        /* XXX EMailSession is too prone to reference leaks to leave
         *     this for our finalize() method.  We want to be sure to
         *     kill the spamd process we started when Evolution shuts
         *     down, so connect to an EShell signal instead. */
        g_signal_connect (
            e_shell_get_default (), "prepare-for-quit",
            G_CALLBACK (spam_assassin_prepare_for_quit),
            extension);
    }

exit:
    g_free (pid_file);
    g_free (socket_path);

    g_mutex_unlock (extension->socket_path_mutex);

    return started;
}

static void
spam_assassin_test_spamd (ESpamAssassin *extension)
{
    const gchar *spamd_binary;
    gboolean try_system_spamd;

    /* XXX SpamAssassin could really benefit from a D-Bus interface
     *     these days.  These tests are just needlessly painful for
     *     clients trying to talk to an already-running spamd. */

    extension->use_spamc = FALSE;
    spamd_binary = extension->spamd_binary;
    try_system_spamd = (g_strcmp0 (spamd_binary, SPAMD_BINARY) == 0);

    if (extension->local_only && try_system_spamd) {
        gint exit_code;

        /* Run a shell command to check for a running
         * spamd process with a -L/--local option or a
         * -p/--port option. */

        const gchar *argv[] = {
            "/bin/sh",
            "-c",
            "ps ax | grep -v grep | "
            "grep -E 'spamd.*(\\-L|\\-\\-local)' | "
            "grep -E -v '\\ \\-p\\ |\\ \\-\\-port\\ '",
            NULL
        };

        exit_code = spam_assassin_command (
            argv, NULL, NULL, NULL, NULL);
        try_system_spamd = (exit_code == 0);
    }

    /* Try to use the system spamd first. */
    if (try_system_spamd) {
        if (spam_assassin_test_spamd_running (extension, TRUE)) {
            extension->use_spamc = TRUE;
            extension->system_spamd_available = TRUE;
        }
    }

    /* If there's no system spamd running, try
     * to use one with a user specified socket. */
    if (!extension->use_spamc && extension->socket_path != NULL) {
        if (spam_assassin_test_spamd_running (extension, FALSE)) {
            extension->use_spamc = TRUE;
            extension->system_spamd_available = FALSE;
        }
    }

    /* Still unsuccessful?  Try to start our own spamd. */
    if (!extension->use_spamc) {
        extension->use_spamc =
            spam_assassin_start_our_own_daemon (extension) &&
            spam_assassin_test_spamd_running (extension, FALSE);
    }
}

static void
spam_assassin_set_property (GObject *object,
                            guint property_id,
                            const GValue *value,
                            GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_LOCAL_ONLY:
            spam_assassin_set_local_only (
                E_SPAM_ASSASSIN (object),
                g_value_get_boolean (value));
            return;

        case PROP_SPAMC_BINARY:
            spam_assassin_set_spamc_binary (
                E_SPAM_ASSASSIN (object),
                g_value_get_string (value));
            return;

        case PROP_SPAMD_BINARY:
            spam_assassin_set_spamd_binary (
                E_SPAM_ASSASSIN (object),
                g_value_get_string (value));
            return;

        case PROP_SOCKET_PATH:
            spam_assassin_set_socket_path (
                E_SPAM_ASSASSIN (object),
                g_value_get_string (value));
            return;

        case PROP_USE_DAEMON:
            spam_assassin_set_use_daemon (
                E_SPAM_ASSASSIN (object),
                g_value_get_boolean (value));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
spam_assassin_get_property (GObject *object,
                            guint property_id,
                            GValue *value,
                            GParamSpec *pspec)
{
    switch (property_id) {
        case PROP_LOCAL_ONLY:
            g_value_set_boolean (
                value, spam_assassin_get_local_only (
                E_SPAM_ASSASSIN (object)));
            return;

        case PROP_SPAMC_BINARY:
            g_value_set_string (
                value, spam_assassin_get_spamc_binary (
                E_SPAM_ASSASSIN (object)));
            return;

        case PROP_SPAMD_BINARY:
            g_value_set_string (
                value, spam_assassin_get_spamd_binary (
                E_SPAM_ASSASSIN (object)));
            return;

        case PROP_SOCKET_PATH:
            g_value_set_string (
                value, spam_assassin_get_socket_path (
                E_SPAM_ASSASSIN (object)));
            return;

        case PROP_USE_DAEMON:
            g_value_set_boolean (
                value, spam_assassin_get_use_daemon (
                E_SPAM_ASSASSIN (object)));
            return;
    }

    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}

static void
spam_assassin_finalize (GObject *object)
{
    ESpamAssassin *extension = E_SPAM_ASSASSIN (object);

    g_mutex_free (extension->socket_path_mutex);

    g_free (extension->pid_file);
    g_free (extension->socket_path);
    g_free (extension->spamc_binary);
    g_free (extension->spamd_binary);

    /* Chain up to parent's finalize() method. */
    G_OBJECT_CLASS (e_spam_assassin_parent_class)->finalize (object);
}

static gboolean
spam_assassin_available (EMailJunkFilter *junk_filter)
{
    ESpamAssassin *extension = E_SPAM_ASSASSIN (junk_filter);
    gboolean available;
    GError *error = NULL;

    available = spam_assassin_get_version (extension, NULL, NULL, &error);

    /* XXX These tests block like crazy so maybe this isn't the best
     *     place to be doing this, but the first available() call is
     *     done at startup before the UI is shown.  So hopefully the
     *     delay will not be noticeable. */
    if (available && extension->use_daemon && !extension->spamd_tested) {
        extension->spamd_tested = TRUE;
        spam_assassin_test_spamd (extension);
        spam_assassin_test_spamd_allow_tell (extension);
    }

    if (error != NULL) {
        g_warning ("%s", error->message);
        g_error_free (error);
    }

    return available;
}

static GtkWidget *
spam_assassin_new_config_widget (EMailJunkFilter *junk_filter)
{
    GtkWidget *box;
    GtkWidget *widget;
    GtkWidget *container;
    gchar *markup;

    box = gtk_box_new (GTK_ORIENTATION_VERTICAL, 12);

    markup = g_markup_printf_escaped (
        "<b>%s</b>", _("SpamAssassin Options"));
    widget = gtk_label_new (markup);
    gtk_misc_set_alignment (GTK_MISC (widget), 0.0, 0.5);
    gtk_label_set_use_markup (GTK_LABEL (widget), TRUE);
    gtk_box_pack_start (GTK_BOX (box), widget, FALSE, FALSE, 0);
    gtk_widget_show (widget);
    g_free (markup);

    widget = gtk_box_new (GTK_ORIENTATION_VERTICAL, 6);
    gtk_box_pack_start (GTK_BOX (box), widget, FALSE, FALSE, 0);
    gtk_widget_show (widget);

    container = widget;

    widget = gtk_check_button_new_with_mnemonic (
        _("I_nclude remote tests"));
    gtk_widget_set_margin_left (widget, 12);
    gtk_box_pack_start (GTK_BOX (container), widget, FALSE, FALSE, 0);
    gtk_widget_show (widget);

    g_object_bind_property (
        junk_filter, "local-only",
        widget, "active",
        G_BINDING_BIDIRECTIONAL |
        G_BINDING_SYNC_CREATE |
        G_BINDING_INVERT_BOOLEAN);

    markup = g_markup_printf_escaped (
        "<small>%s</small>",
        _("This will make SpamAssassin more reliable, but slower."));
    widget = gtk_label_new (markup);
    gtk_widget_set_margin_left (widget, 36);
    gtk_misc_set_alignment (GTK_MISC (widget), 0.0, 0.5);
    gtk_label_set_use_markup (GTK_LABEL (widget), TRUE);
    gtk_box_pack_start (GTK_BOX (container), widget, FALSE, FALSE, 0);
    gtk_widget_show (widget);
    g_free (markup);

    return box;
}

static gboolean
spam_assassin_classify (CamelJunkFilter *junk_filter,
                        CamelMimeMessage *message,
                        CamelJunkStatus *status,
                        GCancellable *cancellable,
                        GError **error)
{
    ESpamAssassin *extension = E_SPAM_ASSASSIN (junk_filter);
    const gchar *argv[7];
    gboolean using_spamc;
    gint exit_code;
    gint ii = 0;

    g_mutex_lock (extension->socket_path_mutex);

    using_spamc = (extension->use_spamc && extension->use_daemon);

    if (using_spamc) {
        argv[ii++] = extension->spamc_binary;
        argv[ii++] = "--check";
        argv[ii++] = "--timeout=60";
        if (!extension->system_spamd_available) {
            argv[ii++] = "--socket";
            argv[ii++] = extension->socket_path;
        }
    } else {
        argv[ii++] = SPAMASSASSIN_BINARY;
        argv[ii++] = "--exit-code";
        if (extension->local_only)
            argv[ii++] = "--local";
    }
    argv[ii] = NULL;

    g_assert (ii < G_N_ELEMENTS (argv));

    exit_code = spam_assassin_command (
        argv, message, NULL, cancellable, error);

    /* For either program, exit code 0 means the message is ham. */
    if (exit_code == 0)
        *status = CAMEL_JUNK_STATUS_MESSAGE_IS_NOT_JUNK;

    /* spamassassin(1) only specifies zero and non-zero exit codes. */
    else if (!using_spamc)
        *status = CAMEL_JUNK_STATUS_MESSAGE_IS_JUNK;

    /* Whereas spamc(1) explicitly states exit code 1 means spam. */
    else if (exit_code == 1)
        *status = CAMEL_JUNK_STATUS_MESSAGE_IS_JUNK;

    /* Consider any other spamc(1) exit code to be inconclusive
     * since it most likely failed to process the message. */
    else
        *status = CAMEL_JUNK_STATUS_INCONCLUSIVE;

    /* Check that the return value and GError agree. */
    if (exit_code != SPAM_ASSASSIN_EXIT_STATUS_ERROR)
        g_warn_if_fail (error == NULL || *error == NULL);
    else
        g_warn_if_fail (error == NULL || *error != NULL);

    g_mutex_unlock (extension->socket_path_mutex);

    return (exit_code != SPAM_ASSASSIN_EXIT_STATUS_ERROR);
}

static gboolean
spam_assassin_learn_junk (CamelJunkFilter *junk_filter,
                          CamelMimeMessage *message,
                          GCancellable *cancellable,
                          GError **error)
{
    ESpamAssassin *extension = E_SPAM_ASSASSIN (junk_filter);
    const gchar *argv[5];
    gint exit_code;
    gint ii = 0;

    if (extension->spamd_using_allow_tell) {
        argv[ii++] = extension->spamc_binary;
        argv[ii++] = "--learntype=spam";
    } else {
        argv[ii++] = SA_LEARN_BINARY;
        argv[ii++] = "--spam";
        if (extension->version >= 3)
            argv[ii++] = "--no-sync";
        else
            argv[ii++] = "--no-rebuild";
        if (extension->local_only)
            argv[ii++] = "--local";
    }
    argv[ii] = NULL;

    g_assert (ii < G_N_ELEMENTS (argv));

    exit_code = spam_assassin_command (
        argv, message, NULL, cancellable, error);

    /* Check that the return value and GError agree. */
    if (exit_code == SPAM_ASSASSIN_EXIT_STATUS_SUCCESS)
        g_warn_if_fail (error == NULL || *error == NULL);
    else
        g_warn_if_fail (error == NULL || *error != NULL);

    return (exit_code == SPAM_ASSASSIN_EXIT_STATUS_SUCCESS);
}

static gboolean
spam_assassin_learn_not_junk (CamelJunkFilter *junk_filter,
                              CamelMimeMessage *message,
                              GCancellable *cancellable,
                              GError **error)
{
    ESpamAssassin *extension = E_SPAM_ASSASSIN (junk_filter);
    const gchar *argv[5];
    gint exit_code;
    gint ii = 0;

    if (extension->spamd_using_allow_tell) {
        argv[ii++] = extension->spamc_binary;
        argv[ii++] = "--learntype=ham";
    } else {
        argv[ii++] = SA_LEARN_BINARY;
        argv[ii++] = "--ham";
        if (extension->version >= 3)
            argv[ii++] = "--no-sync";
        else
            argv[ii++] = "--no-rebuild";
        if (extension->local_only)
            argv[ii++] = "--local";
    }
    argv[ii] = NULL;

    g_assert (ii < G_N_ELEMENTS (argv));

    exit_code = spam_assassin_command (
        argv, message, NULL, cancellable, error);

    /* Check that the return value and GError agree. */
    if (exit_code == SPAM_ASSASSIN_EXIT_STATUS_SUCCESS)
        g_warn_if_fail (error == NULL || *error == NULL);
    else
        g_warn_if_fail (error == NULL || *error != NULL);

    return (exit_code == SPAM_ASSASSIN_EXIT_STATUS_SUCCESS);
}

static gboolean
spam_assassin_synchronize (CamelJunkFilter *junk_filter,
                           GCancellable *cancellable,
                           GError **error)
{
    ESpamAssassin *extension = E_SPAM_ASSASSIN (junk_filter);
    const gchar *argv[4];
    gint exit_code;
    gint ii = 0;

    /* If we're using a spamd that allows learning,
     * there's no need to synchronize anything. */
    if (extension->spamd_using_allow_tell)
        return TRUE;

    argv[ii++] = SA_LEARN_BINARY;
    if (extension->version >= 3)
        argv[ii++] = "--sync";
    else
        argv[ii++] = "--rebuild";
    if (extension->local_only)
        argv[ii++] = "--local";
    argv[ii] = NULL;

    g_assert (ii < G_N_ELEMENTS (argv));

    exit_code = spam_assassin_command (
        argv, NULL, NULL, cancellable, error);

    /* Check that the return value and GError agree. */
    if (exit_code == SPAM_ASSASSIN_EXIT_STATUS_SUCCESS)
        g_warn_if_fail (error == NULL || *error == NULL);
    else
        g_warn_if_fail (error == NULL || *error != NULL);

    return (exit_code == SPAM_ASSASSIN_EXIT_STATUS_SUCCESS);
}

static void
e_spam_assassin_class_init (ESpamAssassinClass *class)
{
    GObjectClass *object_class;
    EMailJunkFilterClass *junk_filter_class;

    object_class = G_OBJECT_CLASS (class);
    object_class->set_property = spam_assassin_set_property;
    object_class->get_property = spam_assassin_get_property;
    object_class->finalize = spam_assassin_finalize;

    junk_filter_class = E_MAIL_JUNK_FILTER_CLASS (class);
    junk_filter_class->filter_name = "SpamAssassin";
    junk_filter_class->display_name = _("SpamAssassin");
    junk_filter_class->available = spam_assassin_available;
    junk_filter_class->new_config_widget = spam_assassin_new_config_widget;

    /* XXX Argh, the boolean sense of the GConf key is inverted from
     *     that of the checkbox widget.  The checkbox wording is more
     *     natural, but GConfBridge doesn't support transform functions
     *     so the property has to match the sense of the GConf key. */
    g_object_class_install_property (
        object_class,
        PROP_LOCAL_ONLY,
        g_param_spec_boolean (
            "local-only",
            "Local Only",
            "Do not use tests requiring DNS lookups",
            TRUE,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_SPAMC_BINARY,
        g_param_spec_string (
            "spamc-binary",
            "spamc Binary",
            "File path for the spamc binary",
            NULL,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_SPAMD_BINARY,
        g_param_spec_string (
            "spamd-binary",
            "spamd Binary",
            "File path for the spamd binary",
            NULL,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_SOCKET_PATH,
        g_param_spec_string (
            "socket-path",
            "Socket Path",
            "Socket path for a SpamAssassin daemon",
            NULL,
            G_PARAM_READWRITE));

    g_object_class_install_property (
        object_class,
        PROP_USE_DAEMON,
        g_param_spec_boolean (
            "use-daemon",
            "Use Daemon",
            "Whether to use a SpamAssassin daemon",
            FALSE,
            G_PARAM_READWRITE));
}

static void
e_spam_assassin_class_finalize (ESpamAssassinClass *class)
{
}

static void
e_spam_assassin_interface_init (CamelJunkFilterInterface *interface)
{
    interface->classify = spam_assassin_classify;
    interface->learn_junk = spam_assassin_learn_junk;
    interface->learn_not_junk = spam_assassin_learn_not_junk;
    interface->synchronize = spam_assassin_synchronize;
}

static void
e_spam_assassin_init (ESpamAssassin *extension)
{
    extension->socket_path_mutex = g_mutex_new ();

    /* XXX Once we move to GSettings these probably don't
     *     need to be properties anymore.  GConfBridge is
     *     just easier to deal with than GConfClient. */

    gconf_bridge_bind_property (
        gconf_bridge_get (),
        "/apps/evolution/mail/junk/sa/local_only",
        G_OBJECT (extension), "local-only");

    gconf_bridge_bind_property (
        gconf_bridge_get (),
        "/apps/evolution/mail/junk/sa/spamc_binary",
        G_OBJECT (extension), "spamc-binary");

    gconf_bridge_bind_property (
        gconf_bridge_get (),
        "/apps/evolution/mail/junk/sa/spamd_binary",
        G_OBJECT (extension), "spamd-binary");

    gconf_bridge_bind_property (
        gconf_bridge_get (),
        "/apps/evolution/mail/junk/sa/socket_path",
        G_OBJECT (extension), "socket-path");

    gconf_bridge_bind_property (
        gconf_bridge_get (),
        "/apps/evolution/mail/junk/sa/use_daemon",
        G_OBJECT (extension), "use-daemon");

    if (extension->spamc_binary == NULL)
        extension->spamc_binary = g_strdup (SPAMC_BINARY);

    if (extension->spamd_binary == NULL)
        extension->spamd_binary = g_strdup (SPAMD_BINARY);
}

G_MODULE_EXPORT void
e_module_load (GTypeModule *type_module)
{
    e_spam_assassin_register_type (type_module);
}

G_MODULE_EXPORT void
e_module_unload (GTypeModule *type_module)
{
}