evolution/camel/camel-store.c

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

/* 
 *
 * Authors:
 *  Bertrand Guiheneuf <bertrand@helixcode.com>
 *  Dan Winship <danw@helixcode.com>
 *
 * Copyright 1999, 2000 Helix Code, Inc. (http://www.helixcode.com)
 *
 * 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 <string.h>

#include "camel-store.h"
#include "camel-folder.h"
#include "camel-exception.h"

#include "camel-private.h"

static CamelServiceClass *parent_class = NULL;

/* Returns the class for a CamelStore */
#define CS_CLASS(so) CAMEL_STORE_CLASS (CAMEL_OBJECT_GET_CLASS(so))

static CamelFolder *get_folder (CamelStore *store, const char *folder_name,
				guint32 flags, CamelException *ex);
static void delete_folder (CamelStore *store, const char *folder_name,
			   CamelException *ex);
static void rename_folder (CamelStore *store, const char *old_name,
			   const char *new_name, CamelException *ex);

static char *get_folder_name (CamelStore *store, const char *folder_name,
			      CamelException *ex);
static char *get_root_folder_name (CamelStore *store, CamelException *ex);
static char *get_default_folder_name (CamelStore *store, CamelException *ex);

static void store_sync (CamelStore *store, CamelException *ex);
static CamelFolderInfo *get_folder_info (CamelStore *store, const char *top,
					 gboolean fast, gboolean recursive,
					 gboolean subscribed_only,
					 CamelException *ex);
static void free_folder_info (CamelStore *store, CamelFolderInfo *tree);

static CamelFolder *lookup_folder (CamelStore *store, const char *folder_name);
static void cache_folder (CamelStore *store, const char *folder_name,
			  CamelFolder *folder);
static void uncache_folder (CamelStore *store, CamelFolder *folder);

static gboolean folder_subscribed (CamelStore *store, const char *folder_name);
static void subscribe_folder (CamelStore *store, const char *folder_name, CamelException *ex);
static void unsubscribe_folder (CamelStore *store, const char *folder_name, CamelException *ex);

static void
camel_store_class_init (CamelStoreClass *camel_store_class)
{
	parent_class = CAMEL_SERVICE_CLASS (camel_type_get_global_classfuncs (camel_service_get_type ()));

	/* virtual method definition */
	camel_store_class->get_folder = get_folder;
	camel_store_class->delete_folder = delete_folder;
	camel_store_class->rename_folder = rename_folder;
	camel_store_class->get_folder_name = get_folder_name;
	camel_store_class->get_root_folder_name = get_root_folder_name;
	camel_store_class->get_default_folder_name = get_default_folder_name;
	camel_store_class->sync = store_sync;
	camel_store_class->get_folder_info = get_folder_info;
	camel_store_class->free_folder_info = free_folder_info;
	camel_store_class->lookup_folder = lookup_folder;
	camel_store_class->cache_folder = cache_folder;
	camel_store_class->uncache_folder = uncache_folder;
	camel_store_class->folder_subscribed = folder_subscribed;
	camel_store_class->subscribe_folder = subscribe_folder;
	camel_store_class->unsubscribe_folder = unsubscribe_folder;
}

static void
camel_store_init (void *o, void *k)
{
	CamelStore *store = o;

	if (store->folders == NULL)
		store->folders = g_hash_table_new (g_str_hash, g_str_equal);
	store->flags = 0;

	store->priv = g_malloc0(sizeof(*store->priv));
#ifdef ENABLE_THREADS
	store->priv->folder_lock = g_mutex_new();
	store->priv->cache_lock = g_mutex_new();
#endif
}

static void
camel_store_finalize (CamelObject *object)
{
	CamelStore *store = CAMEL_STORE (object);

	if (store->folders) {
		if (g_hash_table_size (store->folders) != 0) {
			g_warning ("Folder cache for store %p contains "
				   "%d folders at destruction.", store,
				   g_hash_table_size (store->folders));
		}
		g_hash_table_destroy (store->folders);
	}

#ifdef ENABLE_THREADS
	g_mutex_free(store->priv->folder_lock);
	g_mutex_free(store->priv->cache_lock);
#endif
	g_free(store->priv);
}


CamelType
camel_store_get_type (void)
{
	static CamelType camel_store_type = CAMEL_INVALID_TYPE;

	if (camel_store_type == CAMEL_INVALID_TYPE) {
		camel_store_type = camel_type_register (CAMEL_SERVICE_TYPE, "CamelStore",
							sizeof (CamelStore),
							sizeof (CamelStoreClass),
							(CamelObjectClassInitFunc) camel_store_class_init,
							NULL,
							(CamelObjectInitFunc) camel_store_init,
							(CamelObjectFinalizeFunc) camel_store_finalize );
	}

	return camel_store_type;
}


static CamelFolder *
get_folder(CamelStore *store, const char *folder_name, guint32 flags, CamelException *ex)
{
	g_warning("CamelStore::get_folder not implemented for `%s'",
		  camel_type_to_name(CAMEL_OBJECT_GET_TYPE(store)));
	return NULL;
}

static void
delete_folder (CamelStore *store, const char *folder_name, CamelException *ex)
{
	g_warning ("CamelStore::delete_folder not implemented for `%s'",
		   camel_type_to_name (CAMEL_OBJECT_GET_TYPE (store)));
}

static void
rename_folder (CamelStore *store, const char *old_name,
	       const char *new_name, CamelException *ex)
{
	g_warning ("CamelStore::rename_folder not implemented for `%s'",
		   camel_type_to_name (CAMEL_OBJECT_GET_TYPE (store)));
}


/* CamelStore::get_folder_name should:
 * a) make sure that the provided name is valid
 * b) return it in canonical form, in allocated memory.
 *
 * This is used to make sure that duplicate names for the same folder
 * don't result in duplicate cache entries.
 */
static char *
get_folder_name (CamelStore *store, const char *folder_name,
		 CamelException *ex)
{
	g_warning ("CamelStore::get_folder_name not implemented for `%s'",
		   camel_type_to_name (CAMEL_OBJECT_GET_TYPE (store)));
	return NULL;
}

static char *
get_root_folder_name (CamelStore *store, CamelException *ex)
{
	return g_strdup ("/");
}

static char *
get_default_folder_name (CamelStore *store, CamelException *ex)
{
	return CS_CLASS (store)->get_root_folder_name (store, ex);
}

static CamelFolder *
lookup_folder (CamelStore *store, const char *folder_name)
{
	CamelFolder *folder = NULL;

	CAMEL_STORE_LOCK(store, cache_lock);

	if (store->folders) {
		folder = g_hash_table_lookup (store->folders, folder_name);
		if (folder)
			camel_object_ref(CAMEL_OBJECT(folder));
	}

	CAMEL_STORE_UNLOCK(store, cache_lock);

	return folder;
}

static void folder_finalize (CamelObject *folder, gpointer event_data, gpointer user_data)
{
	CS_CLASS (user_data)->uncache_folder (CAMEL_STORE(user_data), CAMEL_FOLDER(folder));
}

static void
cache_folder (CamelStore *store, const char *folder_name, CamelFolder *folder)
{
	CAMEL_STORE_LOCK(store, cache_lock);

	if (store->folders) {
		if (g_hash_table_lookup (store->folders, folder_name)) {
			g_warning ("Caching folder %s that already exists.", folder_name);
		}
		g_hash_table_insert (store->folders, g_strdup (folder_name), folder);

		camel_object_hook_event (CAMEL_OBJECT (folder), "finalize", folder_finalize, store);
	}

	CAMEL_STORE_UNLOCK(store, cache_lock);

	/*
	 * gt_k so as not to get caught by my little gt_k cleanliness detector.
	 *
	 * gt_k_signal_connect_object (CAMEL_OBJECT (folder), "destroy",
	 *			   GT_K_SIGNAL_FUNC (CS_CLASS (store)->uncache_folder),
	 *			   CAMEL_OBJECT (store));
	 */
}

static gboolean
folder_matches (gpointer key, gpointer value, gpointer user_data)
{
	if (value == user_data) {
		g_free (key);
		return TRUE;
	} else
		return FALSE;
}

static void
uncache_folder (CamelStore *store, CamelFolder *folder)
{
	CAMEL_STORE_LOCK(store, cache_lock);

	g_hash_table_foreach_remove (store->folders, folder_matches, folder);

	CAMEL_STORE_UNLOCK(store, cache_lock);
}


static CamelFolder *
get_folder_internal(CamelStore *store, const char *folder_name, guint32 flags, CamelException *ex)
{
	CamelFolder *folder = NULL;

	/* NB: we already have folder_lock */

	/* Try cache first. */
	folder = CS_CLASS(store)->lookup_folder(store, folder_name);

	if (!folder) {
		folder = CS_CLASS(store)->get_folder(store, folder_name, flags, ex);
		if (!folder)
			return NULL;

		CS_CLASS(store)->cache_folder(store, folder_name, folder);
	}

	return folder;
}



/** 
 * camel_store_get_folder: Return the folder corresponding to a path.
 * @store: a CamelStore
 * @folder_name: name of the folder to get
 * @flags: folder flags (create, save body index, etc)
 * @ex: a CamelException
 * 
 * Returns the folder corresponding to the path @folder_name. If the
 * path begins with the separator character, it is relative to the
 * root folder. Otherwise, it is relative to the default folder.
 *
 * Return value: the folder
 **/
CamelFolder *
camel_store_get_folder(CamelStore *store, const char *folder_name, guint32 flags, CamelException *ex)
{
	char *name;
	CamelFolder *folder = NULL;

	CAMEL_STORE_LOCK(store, folder_lock);

	name = CS_CLASS(store)->get_folder_name(store, folder_name, ex);
	if (name) {
		folder = get_folder_internal(store, name, flags, ex);
		g_free (name);
	}

	CAMEL_STORE_UNLOCK(store, folder_lock);

	return folder;
}


/** 
 * camel_store_delete_folder: Delete the folder corresponding to a path.
 * @store: a CamelStore
 * @folder_name: name of the folder to delete
 * @ex: a CamelException
 * 
 * Deletes the named folder. The folder must be empty.
 **/
void
camel_store_delete_folder (CamelStore *store, const char *folder_name,
			   CamelException *ex)
{
	char *name;

	CAMEL_STORE_LOCK(store, folder_lock);

	name = CS_CLASS (store)->get_folder_name (store, folder_name, ex);
	if (name) {
		CS_CLASS (store)->delete_folder (store, name, ex);
		g_free (name);
	}

	CAMEL_STORE_UNLOCK(store, folder_lock);
}

/**
 * camel_store_rename_folder:
 * @store: 
 * @old_name: 
 * @new_name: 
 * @ex: 
 * 
 * Rename a named folder to a new name.
 **/
void             camel_store_rename_folder      (CamelStore *store,
						 const char *old_name,
						 const char *new_name,
						 CamelException *ex)
{
	char *old, *new;

	CAMEL_STORE_LOCK(store, folder_lock);

	old = CS_CLASS (store)->get_folder_name(store, old_name, ex);
	if (old) {
		new = CS_CLASS (store)->get_folder_name(store, new_name, ex);
		if (new) {
			CS_CLASS (store)->rename_folder(store, old, new, ex);
			g_free(new);
		}
		g_free(old);
	}

	CAMEL_STORE_UNLOCK(store, folder_lock);
}


/**
 * camel_store_get_root_folder: return the top-level folder
 * 
 * Returns the folder which is at the top of the folder hierarchy.
 * This folder may or may not be the same as the default folder.
 * 
 * Return value: the top-level folder.
 **/
CamelFolder *
camel_store_get_root_folder (CamelStore *store, CamelException *ex)
{
	char *name;
	CamelFolder *folder = NULL;

	CAMEL_STORE_LOCK(store, folder_lock);

	name = CS_CLASS (store)->get_root_folder_name (store, ex);
	if (name) {
		folder = get_folder_internal (store, name, CAMEL_STORE_FOLDER_CREATE, ex);
		g_free (name);
	}

	CAMEL_STORE_UNLOCK(store, folder_lock);

	return folder;
}

/** 
 * camel_store_get_default_folder: return the store default folder
 *
 * The default folder is the folder which is presented to the user in
 * the default configuration. This defaults to the root folder if
 * the store doesn't override it.
 *
 * Return value: the default folder.
 **/
CamelFolder *
camel_store_get_default_folder (CamelStore *store, CamelException *ex)
{
	char *name;
	CamelFolder *folder = NULL;

	CAMEL_STORE_LOCK(store, folder_lock);

	name = CS_CLASS (store)->get_default_folder_name (store, ex);
	if (name) {
		folder = get_folder_internal (store, name, CAMEL_STORE_FOLDER_CREATE, ex);
		g_free (name);
	}

	CAMEL_STORE_UNLOCK(store, folder_lock);

	return folder;
}


static void
sync_folder (gpointer key, gpointer folder, gpointer ex)
{
	if (!camel_exception_is_set (ex))
		camel_folder_sync (folder, FALSE, ex);
}

static void
store_sync (CamelStore *store, CamelException *ex)
{
	CAMEL_STORE_LOCK(store, cache_lock);
	g_hash_table_foreach (store->folders, sync_folder, ex);
	CAMEL_STORE_UNLOCK(store, cache_lock);
}

/**
 * camel_store_sync:
 * @store: a CamelStore
 * @ex: a CamelException
 *
 * Syncs any changes that have been made to the store object and its
 * folders with the real store.
 **/
void
camel_store_sync (CamelStore *store, CamelException *ex)
{
	g_return_if_fail (CAMEL_IS_STORE (store));

	CS_CLASS (store)->sync (store, ex);
}


static CamelFolderInfo *
get_folder_info (CamelStore *store, const char *top,
		 gboolean fast, gboolean recursive,
		 gboolean subscribed_only,
		 CamelException *ex)
{
	g_warning ("CamelStore::get_folder_info not implemented for `%s'",
		   camel_type_to_name (CAMEL_OBJECT_GET_TYPE (store)));
	return NULL;
}

/**
 * camel_store_get_folder_info:
 * @store: a CamelStore
 * @top: the name of the folder to start from
 * @fast: whether or not to do a "fast" scan.
 * @recursive: whether to include information for subfolders
 * @ex: a CamelException
 *
 * This fetches information about the folder structure of @store,
 * starting with @top, and returns a tree of CamelFolderInfo
 * structures. If @fast is %TRUE, the message_count or
 * unread_message_count fields of some or all of the structures may be
 * set to -1, if the store cannot determine that information quickly.
 * If @recursive is %TRUE, the returned tree will include all levels of
 * hierarchy below @top. If it is %FALSE, it will only include the
 * immediate subfolders of @top.
 *
 * Return value: a CamelFolderInfo tree, which must be freed with
 * camel_store_free_folder_info.
 **/
CamelFolderInfo *
camel_store_get_folder_info (CamelStore *store, const char *top,
			     gboolean fast, gboolean recursive,
			     gboolean subscribed_only,
			     CamelException *ex)
{
	CamelFolderInfo *ret;

	g_return_val_if_fail (CAMEL_IS_STORE (store), NULL);

	CAMEL_STORE_LOCK(store, folder_lock);

	ret = CS_CLASS (store)->get_folder_info (store, top, fast, recursive, subscribed_only, ex);

	CAMEL_STORE_UNLOCK(store, folder_lock);

	return ret;
}


static void
free_folder_info (CamelStore *store, CamelFolderInfo *fi)
{
	g_warning ("CamelStore::free_folder_info not implemented for `%s'",
		   camel_type_to_name (CAMEL_OBJECT_GET_TYPE (store)));
}

/**
 * camel_store_free_folder_info:
 * @store: a CamelStore
 * @tree: the tree returned by camel_store_get_folder_info()
 *
 * Frees the data returned by camel_store_get_folder_info().
 **/
void
camel_store_free_folder_info (CamelStore *store, CamelFolderInfo *fi)
{
	g_return_if_fail (CAMEL_IS_STORE (store));

	CS_CLASS (store)->free_folder_info (store, fi);
}

/**
 * camel_store_free_folder_info_full:
 * @store: a CamelStore
 * @tree: the tree returned by camel_store_get_folder_info()
 *
 * An implementation for CamelStore::free_folder_info. Frees all
 * of the data.
 **/
void
camel_store_free_folder_info_full (CamelStore *store, CamelFolderInfo *fi)
{
	camel_folder_info_free (fi);
}

/**
 * camel_store_free_folder_info_nop:
 * @store: a CamelStore
 * @tree: the tree returned by camel_store_get_folder_info()
 *
 * An implementation for CamelStore::free_folder_info. Does nothing.
 **/
void
camel_store_free_folder_info_nop (CamelStore *store, CamelFolderInfo *fi)
{
	;
}


/**
 * camel_folder_info_free:
 * @fi: the CamelFolderInfo
 *
 * Frees @fi.
 **/
void
camel_folder_info_free (CamelFolderInfo *fi)
{
	if (fi) {
		camel_folder_info_free (fi->sibling);
		camel_folder_info_free (fi->child);
		g_free (fi->name);
		g_free (fi->full_name);
		g_free (fi->url);
		g_free (fi);
	}
}


/**
 * camel_folder_info_build:
 * @folders: an array of CamelFolderInfo
 * @namespace: an ignorable prefix on the folder names
 * @separator: the hieararchy separator character
 * @short_names: %TRUE if the (short) name of a folder is the part after
 * the last @separator in the full name. %FALSE if it is the full name.
 *
 * This takes an array of folders and attaches them together according
 * to the hierarchy described by their full_names and @separator. If
 * @namespace is non-%NULL, then it will be ignored as a full_name
 * prefix, for purposes of comparison. If necessary,
 * camel_folder_info_build will create additional CamelFolderInfo with
 * %NULL urls to fill in gaps in the tree. The value of @short_names
 * is used in constructing the names of these intermediate folders.
 *
 * Return value: the top level of the tree of linked folder info.
 **/
CamelFolderInfo *
camel_folder_info_build (GPtrArray *folders, const char *namespace,
			 char separator, gboolean short_names)
{
	CamelFolderInfo *fi, *pfi, *top = NULL;
	GHashTable *hash;
	char *name, *p, *pname;
	int i, nlen;

	if (!namespace)
		namespace = "";
	nlen = strlen (namespace);

	/* Hash the folders. */
	hash = g_hash_table_new (g_str_hash, g_str_equal);
	for (i = 0; i < folders->len; i++) {
		fi = folders->pdata[i];
		if (!strncmp (namespace, fi->full_name, nlen))
			g_hash_table_insert (hash, fi->full_name + nlen, fi);
		else
			g_hash_table_insert (hash, fi->full_name, fi);
	}

	/* Now find parents. */
	for (i = 0; i < folders->len; i++) {
		fi = folders->pdata[i];
		if (!strncmp (namespace, fi->full_name, nlen))
			name = fi->full_name + nlen;
		else
			name = fi->full_name;
		p = strrchr (name, separator);
		if (p) {
			pname = g_strndup (name, p - name);
			pfi = g_hash_table_lookup (hash, pname);
			if (pfi) {
				g_free (pname);
			} else {
				pfi = g_new0 (CamelFolderInfo, 1);
				pfi->full_name = pname;
				if (short_names) {
					pfi->name = strrchr (pname, separator);
					if (pfi->name)
						pfi->name = g_strdup (pfi->name + 1);
					else
						pfi->name = g_strdup (pname);
				} else
					pfi->name = g_strdup (pname);
				g_hash_table_insert (hash, pname, pfi);
				g_ptr_array_add (folders, pfi);
			}
			fi->sibling = pfi->child;
			fi->parent = pfi;
			pfi->child = fi;
		} else if (!top)
			top = fi;
	}
	g_hash_table_destroy (hash);

	/* Link together the top-level folders */
	for (i = 0; i < folders->len; i++) {
		fi = folders->pdata[i];
		if (fi->parent || fi == top)
			continue;
		if (top)
			fi->sibling = top;
		top = fi;
	}

	return top;			
}

gboolean
camel_store_supports_subscriptions (CamelStore *store)
{
	return (store->flags & CAMEL_STORE_SUBSCRIPTIONS);
}


static gboolean
folder_subscribed (CamelStore *store, const char *folder_name)
{
	g_warning ("CamelStore::folder_subscribed not implemented for `%s'",
		   camel_type_to_name (CAMEL_OBJECT_GET_TYPE (store)));
	return FALSE;
}

/**
 * camel_store_folder_subscribed: Tell whether or not a folder has been subscribed to.
 * @store: a CamelStore
 * @folder_name: the folder on which we're querying subscribed status.
 * Return value: TRUE if folder is subscribed, FALSE if not.
 **/
gboolean
camel_store_folder_subscribed (CamelStore *store,
			       const char *folder_name)
{
	gboolean ret;

	g_return_val_if_fail (CAMEL_IS_STORE (store), FALSE);
	g_return_val_if_fail (store->flags & CAMEL_STORE_SUBSCRIPTIONS, FALSE);

	CAMEL_STORE_LOCK(store, folder_lock);

	ret = CS_CLASS (store)->folder_subscribed (store, folder_name);

	CAMEL_STORE_UNLOCK(store, folder_lock);

	return ret;
}

static void
subscribe_folder (CamelStore *store, const char *folder_name, CamelException *ex)
{
	g_warning ("CamelStore::subscribe_folder not implemented for `%s'",
		   camel_type_to_name (CAMEL_OBJECT_GET_TYPE (store)));
}

/**
 * camel_store_subscribe_folder: marks a folder as subscribed.
 * @store: a CamelStore
 * @folder_name: the folder to subscribe to.
 **/
void
camel_store_subscribe_folder (CamelStore *store,
			      const char *folder_name,
			      CamelException *ex)
{
	g_return_if_fail (CAMEL_IS_STORE (store));
	g_return_if_fail (store->flags & CAMEL_STORE_SUBSCRIPTIONS);

	CAMEL_STORE_LOCK(store, folder_lock);

	CS_CLASS (store)->subscribe_folder (store, folder_name, ex);

	CAMEL_STORE_UNLOCK(store, folder_lock);
}

static void
unsubscribe_folder (CamelStore *store, const char *folder_name, CamelException *ex)
{
	g_warning ("CamelStore::unsubscribe_folder not implemented for `%s'",
		   camel_type_to_name (CAMEL_OBJECT_GET_TYPE (store)));
}


/**
 * camel_store_unsubscribe_folder: marks a folder as unsubscribed.
 * @store: a CamelStore
 * @folder_name: the folder to unsubscribe from.
 **/
void
camel_store_unsubscribe_folder (CamelStore *store,
				const char *folder_name,
				CamelException *ex)
{
	g_return_if_fail (CAMEL_IS_STORE (store));
	g_return_if_fail (store->flags & CAMEL_STORE_SUBSCRIPTIONS);

	CAMEL_STORE_LOCK(store, folder_lock);

	CS_CLASS (store)->unsubscribe_folder (store, folder_name, ex);

	CAMEL_STORE_UNLOCK(store, folder_lock);
}