path: root/camel/providers/mbox/camel-mbox-folder.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* camel-mbox-folder.c : Abstract class for an email folder */

/* 
 * Author : Bertrand Guiheneuf <bertrand@helixcode.com> 
 *
 * Copyright (C) 1999 Helix Code .
 *
 * This program is free software; you can redistribute it and/or 
 * modify it under the terms of the GNU General Public License as 
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */


#include <config.h> 

#include <sys/types.h>
#include <dirent.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>

#include "camel-mbox-folder.h"
#include "camel-mbox-store.h"
#include "string-utils.h"
#include "camel-log.h"
#include "camel-stream-buffered-fs.h"
#include "camel-folder-summary.h"
#include "camel-mbox-summary.h"
#include "camel-mbox-parser.h"
#include "camel-mbox-utils.h"
#include "md5-utils.h"
#include "gmime-utils.h"

#include "camel-exception.h"

static CamelFolderClass *parent_class=NULL;

/* Returns the class for a CamelMboxFolder */
#define CMBOXF_CLASS(so) CAMEL_MBOX_FOLDER_CLASS (GTK_OBJECT(so)->klass)
#define CF_CLASS(so) CAMEL_FOLDER_CLASS (GTK_OBJECT(so)->klass)
#define CMBOXS_CLASS(so) CAMEL_STORE_CLASS (GTK_OBJECT(so)->klass)


static void _init_with_store (CamelFolder *folder, CamelStore *parent_store, CamelException *ex);
static void _set_name(CamelFolder *folder, const gchar *name, CamelException *ex);


static void _open (CamelFolder *folder, CamelFolderOpenMode mode, CamelException *ex);
static void _close (CamelFolder *folder, gboolean expunge, CamelException *ex);
static gboolean _exists (CamelFolder *folder, CamelException *ex);
static gboolean _create(CamelFolder *folder, CamelException *ex);
static gboolean _delete (CamelFolder *folder, gboolean recurse, CamelException *ex);
static gboolean _delete_messages (CamelFolder *folder, CamelException *ex);
static GList *_list_subfolders (CamelFolder *folder, CamelException *ex);
/* static CamelMimeMessage *_get_message_by_number (CamelFolder *folder, gint number, CamelException *ex);*/
static gint _get_message_count (CamelFolder *folder, CamelException *ex);
#if 0
static gint _append_message (CamelFolder *folder, CamelMimeMessage *message, CamelException *ex);
static void _expunge (CamelFolder *folder, CamelException *ex);
static void _copy_message_to (CamelFolder *folder, CamelMimeMessage *message, CamelFolder *dest_folder, CamelException *ex);
static const gchar *_get_message_uid (CamelFolder *folder, CamelMimeMessage *message, CamelException *ex);
static CamelMimeMessage *_get_message_by_uid (CamelFolder *folder, const gchar *uid, CamelException *ex);
static GList *_get_uid_list  (CamelFolder *folder, CamelException *ex);
#endif

static void _finalize (GtkObject *object);

static void
camel_mbox_folder_class_init (CamelMboxFolderClass *camel_mbox_folder_class)
{
    CamelFolderClass *camel_folder_class = CAMEL_FOLDER_CLASS (camel_mbox_folder_class);
    GtkObjectClass *gtk_object_class = GTK_OBJECT_CLASS (camel_folder_class);

    parent_class = gtk_type_class (camel_folder_get_type ());
        
    /* virtual method definition */

    /* virtual method overload */
    camel_folder_class->init_with_store = _init_with_store;
    camel_folder_class->set_name = _set_name;
    camel_folder_class->open = _open;
    camel_folder_class->close = _close;
    camel_folder_class->exists = _exists;
    camel_folder_class->create = _create;
    camel_folder_class->delete = _delete;
    camel_folder_class->delete_messages = _delete_messages;
    camel_folder_class->list_subfolders = _list_subfolders;
    /* camel_folder_class->get_message_by_number = _get_message_by_number; */
    camel_folder_class->get_message_count = _get_message_count;
#if 0
    camel_folder_class->append_message = _append_message;
    camel_folder_class->expunge = _expunge;
    camel_folder_class->copy_message_to = _copy_message_to;
    camel_folder_class->get_message_uid = _get_message_uid;
    camel_folder_class->get_message_by_uid = _get_message_by_uid;
    camel_folder_class->get_uid_list = _get_uid_list;
#endif
    gtk_object_class->finalize = _finalize;
    
}



static void           
_finalize (GtkObject *object)
{
    CamelMboxFolder *mbox_folder = CAMEL_MBOX_FOLDER (object);

    CAMEL_LOG_FULL_DEBUG ("Entering CamelFolder::finalize\n");

    
    g_free (mbox_folder->folder_file_path);
    g_free (mbox_folder->folder_dir_path);

    GTK_OBJECT_CLASS (parent_class)->finalize (object);
    CAMEL_LOG_FULL_DEBUG ("Leaving CamelFolder::finalize\n");
}





GtkType
camel_mbox_folder_get_type (void)
{
    static GtkType camel_mbox_folder_type = 0;
    
    if (!camel_mbox_folder_type)    {
        GtkTypeInfo camel_mbox_folder_info =    
        {
            "CamelMboxFolder",
            sizeof (CamelMboxFolder),
            sizeof (CamelMboxFolderClass),
            (GtkClassInitFunc) camel_mbox_folder_class_init,
            (GtkObjectInitFunc) NULL,
                /* reserved_1 */ NULL,
                /* reserved_2 */ NULL,
            (GtkClassInitFunc) NULL,
        };
        
        camel_mbox_folder_type = gtk_type_unique (CAMEL_FOLDER_TYPE, &camel_mbox_folder_info);
    }
    
    return camel_mbox_folder_type;
}






static void 
_init_with_store (CamelFolder *folder, CamelStore *parent_store, CamelException *ex)
{
    CamelMboxFolder *mbox_folder = CAMEL_MBOX_FOLDER (folder);


    CAMEL_LOG_FULL_DEBUG ("Entering CamelMhFolder::init_with_store\n");

    /* call parent method */
    parent_class->init_with_store (folder, parent_store, ex);
    if (camel_exception_get_id (ex)) return;

    /* we assume that the parent init_with_store 
       method checks for the existance of @folder */
       
    folder->can_hold_messages = TRUE;
    folder->can_hold_folders = TRUE;
    folder->has_summary_capability = TRUE;
    folder->has_uid_capability = TRUE;
    folder->summary = NULL;

    mbox_folder->folder_file_path = NULL;
    mbox_folder->summary_file_path = NULL;
    mbox_folder->folder_dir_path = NULL;
    mbox_folder->summary = NULL;
    mbox_folder->uid_array = NULL;
    
    CAMEL_LOG_FULL_DEBUG ("Leaving CamelMhFolder::init_with_store\n");
}



/* internal method used to : 
   - test for the existence of a summary file 
   - test the sync between the summary and the mbox file
   - load the summary or create it if necessary 
*/ 
static void
_check_get_or_maybe_generate_summary_file (CamelMboxFolder *mbox_folder, CamelException *ex)
{
    GArray *message_info_array;
    gboolean summary_file_exists;
    gboolean summary_file_is_sync;
    GArray *mbox_summary_info;
    gint mbox_file_fd;
    guint32 next_uid;
    
    /* test for the existence of the summary file */
    summary_file_exists = (access (mbox_folder->summary_file_path, F_OK) == 0);

    /* if the summary file exists, test if the 
       md5 of the mbox file is still in sync
       with the one we had computed the last time
       we saved the summary file */
    if (summary_file_exists) {
        
        summary_file_is_sync = 
            camel_mbox_check_summary_sync (mbox_folder->summary_file_path,
                               mbox_folder->folder_file_path,
                               ex);
        if (camel_exception_get_id (ex)) return;
    }


    /* in the case where the summary does not exist 
       or is not in sync with the mbox file
       regenerate it */
    if ( !(summary_file_exists && summary_file_is_sync)) {
        
        /* parse the mbox folder and get some
           information about the messages */

        mbox_file_fd = open (mbox_folder->folder_file_path, O_RDONLY);
        message_info_array = camel_mbox_parse_file (mbox_file_fd, 
                                "From - ", 
                                0,
                                &next_uid,
                                TRUE,
                                NULL,
                                0,
                                ex); 
        
        close (mbox_file_fd);
        if (camel_exception_get_id (ex)) { 
            return;
        }

        
        next_uid = camel_mbox_write_xev (mbox_folder->folder_file_path, 
                         message_info_array, next_uid, ex);

        if (camel_exception_get_id (ex)) { 
            /* ** FIXME : free the preparsed information */
            return;
        }
                        
        mbox_summary_info =
            parsed_information_to_mbox_summary (message_info_array);
        
        /* **FIXME : Free the parsed information structure */

        /* allocate an internal summary object */
        mbox_folder->summary = g_new (CamelMboxSummary, 1);
        
        /* generate the folder md5 signature */
        md5_get_digest_from_file (mbox_folder->folder_file_path, mbox_folder->summary->md5_digest);

        /* store the number of messages as well as the summary array */
        mbox_folder->summary->nb_message = mbox_summary_info->len;      
        mbox_folder->summary->next_uid = next_uid;      
        mbox_folder->summary->message_info = mbox_summary_info;
        
    } else {
        /* every thing seems ok, just read the summary file from disk */
        mbox_folder->summary = camel_mbox_load_summary ("ev-summary.mbox", ex);
    }
}



static void
_open (CamelFolder *folder, CamelFolderOpenMode mode, CamelException *ex)
{
    CamelMboxFolder *mbox_folder = CAMEL_MBOX_FOLDER (folder);
    //struct dirent *dir_entry;
    //struct stat stat_buf;


    if (folder->open_state == FOLDER_OPEN) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_INVALID_STATE,
                     "folder is already open");
        return;
    }
    
    
    
    /* get (or create) uid list */
    //if (!(mbox_load_uid_list (mbox_folder) > 0))
    //  mbox_generate_uid_list (mbox_folder);
    
    _check_get_or_maybe_generate_summary_file (mbox_folder, ex);
}


static void
_close (CamelFolder *folder, gboolean expunge, CamelException *ex)
{
    CamelMboxFolder *mbox_folder = CAMEL_MBOX_FOLDER (folder);


    /* call parent implementation */
    parent_class->close (folder, expunge, ex);
    
    /* save the folder summary on disc */
    camel_mbox_save_summary (mbox_folder->summary, mbox_folder->summary_file_path, ex);
}




static void
_set_name (CamelFolder *folder, const gchar *name, CamelException *ex)
{
    CamelMboxFolder *mbox_folder = CAMEL_MBOX_FOLDER (folder);
    const gchar *root_dir_path;
    //gchar *full_name;
    //const gchar *parent_full_name;
    gchar separator;
    
    CAMEL_LOG_FULL_DEBUG ("Entering CamelMboxFolder::set_name\n");

    /* call default implementation */
    parent_class->set_name (folder, name, ex);
    if (camel_exception_get_id (ex)) return;

    g_free (mbox_folder->folder_file_path);
    g_free (mbox_folder->folder_dir_path);

    separator = camel_store_get_separator (folder->parent_store);
    root_dir_path = camel_mbox_store_get_toplevel_dir (CAMEL_MBOX_STORE(folder->parent_store));

    CAMEL_LOG_FULL_DEBUG ("CamelMboxFolder::set_name full_name is %s\n", folder->full_name);
    CAMEL_LOG_FULL_DEBUG ("CamelMboxFolder::set_name root_dir_path is %s\n", root_dir_path);
    CAMEL_LOG_FULL_DEBUG ("CamelMboxFolder::separator is %c\n", separator);

    mbox_folder->folder_file_path = g_strdup_printf ("%s%c%s", root_dir_path, separator, folder->full_name);
    mbox_folder->summary_file_path = g_strdup_printf ("%s%c.%s-ev-summary", root_dir_path, separator, folder->full_name);
    mbox_folder->folder_dir_path = g_strdup_printf ("%s%c%s.sdb", root_dir_path, separator, folder->full_name);
    
    
    CAMEL_LOG_FULL_DEBUG ("CamelMboxFolder::set_name mbox_folder->folder_file_path is %s\n", 
                  mbox_folder->folder_file_path);
    CAMEL_LOG_FULL_DEBUG ("CamelMboxFolder::set_name mbox_folder->folder_dir_path is %s\n", 
                  mbox_folder->folder_dir_path);
    CAMEL_LOG_FULL_DEBUG ("Leaving CamelMboxFolder::set_name\n");
}






static gboolean
_exists (CamelFolder *folder, CamelException *ex)
{
    CamelMboxFolder *mbox_folder = CAMEL_MBOX_FOLDER(folder);
    struct stat stat_buf;
    gint stat_error;
    gboolean exists;

    CAMEL_LOG_FULL_DEBUG ("Entering CamelMboxFolder::exists\n");

    /* check if the folder object exists */
    if (!folder) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_NULL,
                     "folder object is NULL");
        return FALSE;
    }

    /* check if the mbox file path is determined */
    if (!mbox_folder->folder_file_path) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_INVALID,
                     "undetermined folder file path. Maybe use set_name ?");
        return FALSE;
    }

    /* check if the mbox dir path is determined */
    if (!mbox_folder->folder_dir_path) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_INVALID,
                     "undetermined folder directory path. Maybe use set_name ?");
        return FALSE;
    }


    /* we should not check for that here */
#if 0
    /* check if the mbox directory exists */
    access_result = access (mbox_folder->folder_dir_path, F_OK);
    if (access_result < 0) {
        CAMEL_LOG_FULL_DEBUG ("CamelMboxFolder::exists errot when executing access on %s\n", 
                      mbox_folder->folder_dir_path);
        CAMEL_LOG_FULL_DEBUG ("  Full error text is : %s\n", strerror(errno));
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_SYSTEM,
                     strerror(errno));
        return FALSE;
    }
    stat_error = stat (mbox_folder->folder_dir_path, &stat_buf);
    if (stat_error == -1)  {
        CAMEL_LOG_FULL_DEBUG ("CamelMboxFolder::exists when executing stat on %s, stat_error = %d\n", 
                      mbox_folder->folder_dir_path, stat_error);
        CAMEL_LOG_FULL_DEBUG ("  Full error text is : %s\n", strerror(errno));
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_SYSTEM,
                     strerror(errno));
        return FALSE;
    }
    exists = S_ISDIR (stat_buf.st_mode);
    if (!exists) return FALSE;
#endif 


    /* check if the mbox file exists */
    stat_error = stat (mbox_folder->folder_file_path, &stat_buf);
    if (stat_error == -1)
        return FALSE;
    
    exists = S_ISREG (stat_buf.st_mode);
    /* we should  check the rights here  */
    
    CAMEL_LOG_FULL_DEBUG ("Leaving CamelMboxFolder::exists\n");
    return exists;
}








static gboolean
_create (CamelFolder *folder, CamelException *ex)
{
    CamelMboxFolder *mbox_folder = CAMEL_MBOX_FOLDER(folder);
    const gchar *folder_file_path, *folder_dir_path;
    mode_t dir_mode = S_IRWXU;
    gint mkdir_error;
    gboolean folder_already_exists;
    int creat_fd;
    mode_t old_umask;

    /* check if the folder object exists */
    if (!folder) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_NULL,
                     "folder object is NULL");
        return FALSE;
    }


    /* call default implementation */
    parent_class->create (folder, ex);

    /* get the paths of what we need to create */
    folder_file_path = mbox_folder->folder_file_path;
    folder_dir_path = mbox_folder->folder_file_path;
    
    if (!(folder_file_path || folder_dir_path)) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_INVALID,
                     "invalid folder path. Use set_name ?");
        return FALSE;
    }

    
    /* if the folder already exists, simply return */
    folder_already_exists = camel_folder_exists (folder,ex);
    if (camel_exception_get_id (ex)) return FALSE;

    if (folder_already_exists) return TRUE;


    /* create the directory for the subfolders */
    mkdir_error = mkdir (folder_dir_path, dir_mode);
    if (mkdir_error == -1) goto io_error;
    

    /* create the mbox file */ 
    /* it must be rw for the user and none for the others */
    old_umask = umask (0700);
    creat_fd = open (folder_file_path, 
             O_WRONLY | O_CREAT | O_APPEND,
             S_IRUSR  | S_IWUSR); 
    umask (old_umask);
    if (creat_fd == -1) goto io_error;
    close (creat_fd);

    /* create the summary object */ 
    mbox_folder->summary = g_new (CamelMboxSummary, 1);
    mbox_folder->summary->nb_message = 0;
    mbox_folder->summary->next_uid = 1;
    mbox_folder->summary->message_info = g_array_new (FALSE, FALSE, sizeof (CamelMboxSummaryInformation));

    return TRUE;

    /* exception handling for io errors */
    io_error :

        CAMEL_LOG_WARNING ("CamelMboxFolder::create, error when creating %s and %s\n", 
                   folder_dir_path, folder_file_path);
        CAMEL_LOG_FULL_DEBUG ( "  Full error text is : %s\n", strerror(errno));

        if (errno == EACCES) {
            camel_exception_set (ex, 
                         CAMEL_EXCEPTION_FOLDER_INSUFFICIENT_PERMISSION,
                         "You don't have the permission to create the mbox file.");
            return FALSE;
        } else {
            camel_exception_set (ex, 
                         CAMEL_EXCEPTION_SYSTEM,
                         "Unable to create the mbox file.");
            return FALSE;
        }
}








static gboolean
_delete (CamelFolder *folder, gboolean recurse, CamelException *ex)
{
    CamelMboxFolder *mbox_folder = CAMEL_MBOX_FOLDER(folder);
    const gchar *folder_file_path, *folder_dir_path;
    gint rmdir_error = 0;
    gint unlink_error = 0;
    gboolean folder_already_exists;

    /* check if the folder object exists */
    if (!folder) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_NULL,
                     "folder object is NULL");
        return FALSE;
    }


    /* in the case where the folder does not exist, 
       return immediatly */
    folder_already_exists = camel_folder_exists (folder, ex);
    if (camel_exception_get_id (ex)) return FALSE;

    if (!folder_already_exists) return TRUE;


    /* call default implementation.
       It should delete the messages in the folder
       and recurse the operation to subfolders */
    parent_class->delete (folder, recurse, ex);
    

    /* get the paths of what we need to be deleted */
    folder_file_path = mbox_folder->folder_file_path;
    folder_dir_path = mbox_folder->folder_file_path;
    
    if (!(folder_file_path || folder_dir_path)) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_INVALID,
                     "invalid folder path. Use set_name ?");
        return FALSE;
    }

    
    /* physically delete the directory */
    CAMEL_LOG_FULL_DEBUG ("CamelMboxFolder::delete removing directory %s\n", folder_dir_path);
    rmdir_error = rmdir (folder_dir_path);
    if (rmdir_error == -1) 
        switch errno { 
        case EACCES :
            camel_exception_set (ex, 
                         CAMEL_EXCEPTION_FOLDER_INSUFFICIENT_PERMISSION,
                         "Not enough permission to delete the mbox folder");
            return FALSE;           
            break;
            
        case ENOTEMPTY :
                camel_exception_set (ex, 
                         CAMEL_EXCEPTION_FOLDER_NON_EMPTY,
                             "mbox folder not empty. Cannot delete it. Maybe use recurse flag ?");
                return FALSE;       
                break;
        default :
            camel_exception_set (ex, 
                         CAMEL_EXCEPTION_SYSTEM,
                         "Unable to delete the mbox folder.");
            return FALSE;
    }
    
    /* physically delete the file */
    unlink_error = unlink (folder_dir_path);
    if (unlink_error == -1) 
        switch errno { 
        case EACCES :
        case EPERM :
        case EROFS :
            camel_exception_set (ex, 
                         CAMEL_EXCEPTION_FOLDER_INSUFFICIENT_PERMISSION,
                         "Not enough permission to delete the mbox file");
            return FALSE;           
            break;
            
        case EFAULT :
        case ENOENT :
        case ENOTDIR :
        case EISDIR :
            camel_exception_set (ex, 
                         CAMEL_EXCEPTION_FOLDER_INVALID_PATH,
                         "Invalid mbox file");
            return FALSE;           
            break;

        default :
            camel_exception_set (ex, 
                         CAMEL_EXCEPTION_SYSTEM,
                         "Unable to delete the mbox folder.");
            return FALSE;
    }


    return TRUE;
}




gboolean
_delete_messages (CamelFolder *folder, CamelException *ex)
{
    
    CamelMboxFolder *mbox_folder = CAMEL_MBOX_FOLDER(folder);
    const gchar *folder_file_path;
    gboolean folder_already_exists;
    int creat_fd;
    mode_t old_umask;
    

    /* check if the folder object exists */
    if (!folder) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_NULL,
                     "folder object is NULL");
        return FALSE;
    }

    /* in the case where the folder does not exist, 
       return immediatly */
    folder_already_exists = camel_folder_exists (folder, ex);
    if (camel_exception_get_id (ex)) return FALSE;

    if (!folder_already_exists) return TRUE;



    /* get the paths of the mbox file we need to delete */
    folder_file_path = mbox_folder->folder_file_path;
    
    if (!folder_file_path) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_INVALID,
                     "invalid folder path. Use set_name ?");
        return FALSE;
    }

        
    /* create the mbox file */ 
    /* it must be rw for the user and none for the others */
    old_umask = umask (0700);
    creat_fd = open (folder_file_path, 
             O_WRONLY | O_TRUNC,
             S_IRUSR  | S_IWUSR); 
    umask (old_umask);
    if (creat_fd == -1) goto io_error;
    close (creat_fd);
    
    return TRUE;

    /* exception handling for io errors */
    io_error :

        CAMEL_LOG_WARNING ("CamelMboxFolder::create, error when deleting files  %s\n", 
                   folder_file_path);
        CAMEL_LOG_FULL_DEBUG ( "  Full error text is : %s\n", strerror(errno));

        if (errno == EACCES) {
            camel_exception_set (ex, 
                         CAMEL_EXCEPTION_FOLDER_INSUFFICIENT_PERMISSION,
                         "You don't have the permission to write in the mbox file.");
            return FALSE;
        } else {
            camel_exception_set (ex, 
                         CAMEL_EXCEPTION_SYSTEM,
                         "Unable to write in the mbox file.");
            return FALSE;
        }
    

}









static GList *
_list_subfolders (CamelFolder *folder, CamelException *ex)
{
    GList *subfolder_name_list = NULL;

    CamelMboxFolder *mbox_folder = CAMEL_MBOX_FOLDER(folder);
    const gchar *folder_dir_path;
    gboolean folder_exists;

    struct stat stat_buf;
    gint stat_error = 0;
    //GList *file_list;
    gchar *entry_name;
    gchar *full_entry_name;
    gchar *real_folder_name;
    struct dirent *dir_entry;
    DIR *dir_handle;
    gboolean folder_suffix_found;
    
    //gchar *io_error_text;
    


    /* check if the folder object exists */
    if (!folder) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_NULL,
                     "folder object is NULL");
        return FALSE;
    }


    /* in the case the folder does not exist, 
       raise an exception */
    folder_exists = camel_folder_exists (folder, ex);
    if (camel_exception_get_id (ex)) return FALSE;

    if (!folder_exists) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_INVALID,
                     "Inexistant folder.");
        return FALSE;
    }


    /* get the mbox subfolders directories */
    folder_dir_path = mbox_folder->folder_file_path;
    if (!folder_dir_path) {
        camel_exception_set (ex, 
                     CAMEL_EXCEPTION_FOLDER_INVALID,
                     "Invalid folder path. Use set_name ?");
        return FALSE;
    }

        
    dir_handle = opendir (folder_dir_path);
    
    /* read the first entry in the directory */
    dir_entry = readdir (dir_handle);
    while ((stat_error != -1) && (dir_entry != NULL)) {

        /* get the name of the next entry in the dir */
        entry_name = dir_entry->d_name;
        full_entry_name = g_strdup_printf ("%s/%s", folder_dir_path, entry_name);
        stat_error = stat (full_entry_name, &stat_buf);
        g_free (full_entry_name);

        /* is it a directory ? */
        if ((stat_error != -1) && S_ISDIR (stat_buf.st_mode)) {
            /* yes, add it to the list */
            if (entry_name[0] != '.') {
                CAMEL_LOG_FULL_DEBUG ("CamelMboxFolder::list_subfolders adding "
                              "%s\n", entry_name);

                /* if the folder is a netscape folder, remove the  
                   ".sdb" from the name */
                real_folder_name = string_prefix (entry_name, ".sdb", &folder_suffix_found);
                /* stick here the tests for other folder suffixes if any */
                
                if (!folder_suffix_found) real_folder_name = g_strdup (entry_name);
                
                /* add the folder name to the list */
                subfolder_name_list = g_list_append (subfolder_name_list, 
                                     real_folder_name);
            }
        }
        /* read next entry */
        dir_entry = readdir (dir_handle);
    }

    closedir (dir_handle);

    return subfolder_name_list;

    

    /* io exception handling */
    io_error : 

        switch errno { 
        case EACCES :
            
            camel_exception_setv (ex, 
                          CAMEL_EXCEPTION_FOLDER_INSUFFICIENT_PERMISSION,
                          "Unable to list the directory. Full Error text is : %s ", 
                          strerror (errno));
            break;
            
        case ENOENT :
        case ENOTDIR :
            camel_exception_setv (ex, 
                          CAMEL_EXCEPTION_FOLDER_INVALID_PATH,
                          "Invalid mbox folder path. Full Error text is : %s ", 
                          strerror (errno));
            break;
            
        default :
            camel_exception_set (ex, 
                         CAMEL_EXCEPTION_SYSTEM,
                         "Unable to delete the mbox folder.");
            
        }
    
    g_list_free (subfolder_name_list);
    return NULL;
}




static gint
_get_message_count (CamelFolder *folder, CamelException *ex)
{
    
    CamelMboxFolder *mbox_folder = CAMEL_MBOX_FOLDER(folder);
    gint message_count;

    g_assert (folder);
    g_assert (mbox_folder->summary);
    
    message_count = mbox_folder->summary->nb_message;

    CAMEL_LOG_FULL_DEBUG ("CamelMboxFolder::get_message_count found %d messages\n", message_count);
    return message_count;
}