path: root/addressbook/backend/pas/pas-backend-file.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
 * Author:
 *   Nat Friedman (nat@helixcode.com)
 *
 * Copyright 2000, Helix Code, Inc.
 */

#include "config.h"  
#include <gtk/gtksignal.h>
#include <fcntl.h>
#include <time.h>
#ifdef HAVE_DB_185_H
#include <db_185.h>
#else
#include <db.h>
#endif

#include <pas-backend-file.h>
#include <pas-book.h>
#include <pas-card-cursor.h>

#define PAS_BACKEND_FILE_VERSION_NAME "PAS-DB-VERSION"
#define PAS_BACKEND_FILE_VERSION "0.1"

static PASBackendClass *pas_backend_file_parent_class;
typedef struct _PASBackendFileCursorPrivate PASBackendFileCursorPrivate;

struct _PASBackendFilePrivate {
    GList    *clients;
    gboolean  loaded;
    DB       *file_db;
};

struct _PASBackendFileCursorPrivate {
    PASBackend *backend;
    PASBook    *book;

    GList      *elements;
    guint32    num_elements;
};

static long
get_length(PASCardCursor *cursor, gpointer data)
{
    PASBackendFileCursorPrivate *cursor_data = (PASBackendFileCursorPrivate *) data;

    return cursor_data->num_elements;
}

static char *
get_nth(PASCardCursor *cursor, long n, gpointer data)
{
    PASBackendFileCursorPrivate *cursor_data = (PASBackendFileCursorPrivate *) data;
    GList *nth_item = g_list_nth(cursor_data->elements, n);

    return g_strdup((char*)nth_item->data);
}

static void
cursor_destroy(GtkObject *object, gpointer data)
{
    CORBA_Environment ev;
    Evolution_Book corba_book;
    PASBackendFileCursorPrivate *cursor_data = (PASBackendFileCursorPrivate *) data;

    corba_book = bonobo_object_corba_objref(BONOBO_OBJECT(cursor_data->book));

    CORBA_exception_init(&ev);

    Evolution_Book_unref(corba_book, &ev);
    
    if (ev._major != CORBA_NO_EXCEPTION) {
        g_warning("cursor_destroy: Exception unreffing "
              "corba book.\n");
    }

    CORBA_exception_free(&ev);

    g_list_foreach(cursor_data->elements, (GFunc)g_free, NULL);
    g_list_free (cursor_data->elements);

    g_free(cursor_data);
}

static void
string_to_dbt(const char *str, DBT *dbt)
{
    dbt->data = (void*)str;
    dbt->size = strlen (str);
}

static char *
pas_backend_file_create_unique_id (char *vcard)
{
    /* use a 32 counter and the 32 bit timestamp to make an id.
       it's doubtful 2^32 id's will be created in a second, so we
       should be okay. */
    static guint c = 0;
    return g_strdup_printf ("pas-id-%08lX%08X", time(NULL), c++);
}

static void
pas_backend_file_process_create_card (PASBackend *backend,
                      PASBook    *book,
                      PASRequest *req)
{
    PASBackendFile *bf = PAS_BACKEND_FILE (backend);
    DB             *db = bf->priv->file_db;
    DBT            id_dbt, vcard_dbt;
    int            db_error;
    char           *id;

    id = pas_backend_file_create_unique_id (req->vcard);

    string_to_dbt (id, &id_dbt);
    string_to_dbt (req->vcard, &vcard_dbt);

    db_error = db->put (db, &id_dbt, &vcard_dbt, 0);

    if (0 == db_error) {
#if 0
        pas_book_notify_add(book, id);
#endif

        pas_book_respond_create (
                 book,
                 Evolution_BookListener_Success,
                 id);

        db_error = db->sync (db, 0);
        if (db_error != 0)
            g_warning ("db->sync failed.\n");
    }
    else {
        /* XXX need a different call status for this case, i
                   think */
        pas_book_respond_create (
                 book,
                 Evolution_BookListener_CardNotFound,
                 "");
    }

    g_free (id);
    g_free (req->vcard);
}

static void
pas_backend_file_process_remove_card (PASBackend *backend,
                      PASBook    *book,
                      PASRequest *req)
{
    PASBackendFile *bf = PAS_BACKEND_FILE (backend);
    DB             *db = bf->priv->file_db;
    DBT            id_dbt;
    int            db_error;

    string_to_dbt (req->id, &id_dbt);

    db_error = db->del (db, &id_dbt, 0);

    if (0 == db_error) {
#if 0
        pas_book_notify_remove (book, req->id);
#endif

        pas_book_respond_remove (
                  book,
                  Evolution_BookListener_Success);

        db_error = db->sync (db, 0);
        if (db_error != 0)
            g_warning ("db->sync failed.\n");
    }
    else {
        pas_book_respond_remove (
                 book,
                 Evolution_BookListener_CardNotFound);
    }

    g_free (req->id);
}

static void
pas_backend_file_process_modify_card (PASBackend *backend,
                      PASBook    *book,
                      PASRequest *req)
{
    PASBackendFile *bf = PAS_BACKEND_FILE (backend);
    DB             *db = bf->priv->file_db;
    DBT            id_dbt, vcard_dbt;
    int            db_error;

    string_to_dbt (req->id, &id_dbt);
    string_to_dbt (req->vcard, &vcard_dbt); 

    db_error = db->put (db, &id_dbt, &vcard_dbt, 0);

    if (0 == db_error) {
#if 0
        pas_book_notify_change (book, req->id);
#endif

        pas_book_respond_modify (
                 book,
                 Evolution_BookListener_Success);

        db_error = db->sync (db, 0);
        if (db_error != 0)
            g_warning ("db->sync failed.\n");
    }
    else {
        pas_book_respond_modify (
                 book,
                 Evolution_BookListener_CardNotFound);
    }

    g_free (req->vcard);
}

static void
pas_backend_file_build_all_cards_list(PASBackend *backend,
                      PASBackendFileCursorPrivate *cursor_data)
{
      PASBackendFile *bf = PAS_BACKEND_FILE (backend);
      DB             *db = bf->priv->file_db;
      int            db_error;
      DBT  id_dbt, vcard_dbt;
  
      cursor_data->elements = NULL;
      
      db_error = db->seq(db, &id_dbt, &vcard_dbt, R_FIRST);

      while (db_error == 0) {

          /* don't include the version in the list of cards */
          if (id_dbt.size != strlen(PAS_BACKEND_FILE_VERSION_NAME)
              || strncmp (id_dbt.data, PAS_BACKEND_FILE_VERSION_NAME, id_dbt.size)) {

              cursor_data->elements = g_list_append(cursor_data->elements,
                                g_strndup(vcard_dbt.data,
                                      vcard_dbt.size));
          }

          db_error = db->seq(db, &id_dbt, &vcard_dbt, R_NEXT);

      }

      if (db_error == -1) {
          g_warning ("pas_backend_file_build_all_cards_list: error building list\n");
      }
      else {
          cursor_data->num_elements = g_list_length (cursor_data->elements);
      }
}

static void
pas_backend_file_process_get_cursor (PASBackend *backend,
                     PASBook    *book,
                     PASRequest *req)
{
    /*
      PASBackendFile *bf = PAS_BACKEND_FILE (backend);
      DB             *db = bf->priv->file_db;
      DBT            id_dbt, vcard_dbt;
    */
    CORBA_Environment ev;
    int            db_error = 0;
    PASBackendFileCursorPrivate *cursor_data;
    PASCardCursor *cursor;
    Evolution_Book corba_book;

    cursor_data = g_new(PASBackendFileCursorPrivate, 1);
    cursor_data->backend = backend;
    cursor_data->book = book;

    pas_backend_file_build_all_cards_list(backend, cursor_data);

    corba_book = bonobo_object_corba_objref(BONOBO_OBJECT(book));

    CORBA_exception_init(&ev);

    Evolution_Book_ref(corba_book, &ev);
    
    if (ev._major != CORBA_NO_EXCEPTION) {
        g_warning("pas_backend_file_process_get_cursor: Exception reffing "
              "corba book.\n");
    }

    CORBA_exception_free(&ev);
    
    cursor = pas_card_cursor_new(get_length,
                     get_nth,
                     cursor_data);

    gtk_signal_connect(GTK_OBJECT(cursor), "destroy",
               GTK_SIGNAL_FUNC(cursor_destroy), cursor_data);
    
    pas_book_respond_get_cursor (
        book,
        (db_error == 0 
         ? Evolution_BookListener_Success 
         : Evolution_BookListener_CardNotFound),
        cursor);
}

static void
pas_backend_file_process_get_book_view (PASBackend *backend,
                    PASBook    *book,
                    PASRequest *req)
{
    /*
      PASBackendFile *bf = PAS_BACKEND_FILE (backend);
      DB             *db = bf->priv->file_db;
      DBT            id_dbt, vcard_dbt;
    */
    CORBA_Environment ev;
    int            db_error = 0;
    PASBackendFileCursorPrivate *cursor_data;
    PASCardCursor *cursor;
    Evolution_Book corba_book;

    cursor_data = g_new(PASBackendFileCursorPrivate, 1);
    cursor_data->backend = backend;
    cursor_data->book = book;

    pas_backend_file_build_all_cards_list(backend, cursor_data);

    corba_book = bonobo_object_corba_objref(BONOBO_OBJECT(book));

    CORBA_exception_init(&ev);

    Evolution_Book_ref(corba_book, &ev);
    
    if (ev._major != CORBA_NO_EXCEPTION) {
        g_warning("pas_backend_file_process_get_book_view: Exception reffing "
              "corba book.\n");
    }

    CORBA_exception_free(&ev);
    
    cursor = pas_card_cursor_new(get_length,
                     get_nth,
                     cursor_data);

    gtk_signal_connect(GTK_OBJECT(cursor), "destroy",
               GTK_SIGNAL_FUNC(cursor_destroy), cursor_data);
    
    pas_book_respond_get_cursor (
        book,
        (db_error == 0 
         ? Evolution_BookListener_Success 
         : Evolution_BookListener_CardNotFound),
        cursor);
}

static void
pas_backend_file_process_check_connection (PASBackend *backend,
                       PASBook    *book,
                       PASRequest *req)
{
    PASBackendFile *bf = PAS_BACKEND_FILE (backend);

    pas_book_report_connection (book, bf->priv->file_db != NULL);
}

static void
pas_backend_file_process_client_requests (PASBook *book)
{
    PASBackend *backend;
    PASRequest *req;

    backend = pas_book_get_backend (book);

    req = pas_book_pop_request (book);
    if (req == NULL)
        return;

    switch (req->op) {
    case CreateCard:
        pas_backend_file_process_create_card (backend, book, req);
        break;

    case RemoveCard:
        pas_backend_file_process_remove_card (backend, book, req);
        break;

    case ModifyCard:
        pas_backend_file_process_modify_card (backend, book, req);
        break;

    case CheckConnection:
        pas_backend_file_process_check_connection (backend, book, req);
        break;
        
    case GetCursor:
        pas_backend_file_process_get_cursor (backend, book, req);
        break;
        
    case GetBookView:
        pas_backend_file_process_get_book_view (backend, book, req);
        break;
    }

    g_free (req);
}

static void
pas_backend_file_book_destroy_cb (PASBook *book)
{
    PASBackendFile *backend;

    backend = PAS_BACKEND_FILE (pas_book_get_backend (book));

    pas_backend_remove_client (PAS_BACKEND (backend), book);
}

static char *
pas_backend_file_get_vcard (PASBook *book, const char *id)
{
    PASBackendFile *bf;
    DBT            id_dbt, vcard_dbt;
    DB             *db;
    int            db_error;

    bf = PAS_BACKEND_FILE (pas_book_get_backend (book));
    db = bf->priv->file_db;

    string_to_dbt (id, &id_dbt);

    db_error = db->get (db, &id_dbt, &vcard_dbt, 0);
    if (db_error == 0) {
        /* success */
        return g_strndup (vcard_dbt.data, vcard_dbt.size);
    }
    else if (db_error == 1) {
        /* key was not in file */
        return g_strdup (""); /* XXX */
    }
    else /* if (db_error < 0)*/ {
        /* error */
        return g_strdup (""); /* XXX */
    }
}

static char *
pas_backend_file_extract_path_from_uri (const char *uri)
{
    g_assert (strncasecmp (uri, "file:", 5) == 0);

    return g_strdup (uri + 5);
}

static gboolean
pas_backend_file_upgrade_db (PASBackendFile *bf, char *old_version)
{
    if (!strcmp (old_version, "0.0")) {
        /* 0.0 is the same as 0.1, we just need to add the version */
        DB  *db = bf->priv->file_db;
        DBT version_name_dbt, version_dbt;
        int db_error;

        string_to_dbt (PAS_BACKEND_FILE_VERSION_NAME, &version_name_dbt);
        string_to_dbt (PAS_BACKEND_FILE_VERSION, &version_dbt);

        db_error = db->put (db, &version_name_dbt, &version_dbt, 0);
        if (db_error == 0)
            return TRUE;
        else
            return FALSE;
    }
    else {
        g_warning ("unsupported version '%s' found in PAS backend file\n",
               old_version);
        return FALSE;
    }
}

static gboolean
pas_backend_file_maybe_upgrade_db (PASBackendFile *bf)
{
    DB   *db = bf->priv->file_db;
    DBT  version_name_dbt, version_dbt;
    int  db_error;
    char *version;
    gboolean ret_val = TRUE;

    string_to_dbt (PAS_BACKEND_FILE_VERSION_NAME, &version_name_dbt);

    db_error = db->get (db, &version_name_dbt, &version_dbt, 0);
    if (db_error == 0) {
        /* success */
        version = g_strndup (version_dbt.data, version_dbt.size);
    }
    else {
        /* key was not in file */
        version = g_strdup ("0.0");
    }

    if (strcmp (version, PAS_BACKEND_FILE_VERSION))
        ret_val = pas_backend_file_upgrade_db (bf, version);

    g_free (version);

    return ret_val;
}

static void
pas_backend_file_load_uri (PASBackend             *backend,
               const char             *uri)
{
    PASBackendFile *bf = PAS_BACKEND_FILE (backend);
    char           *filename;

    g_assert (bf->priv->loaded == FALSE);

    filename = pas_backend_file_extract_path_from_uri (uri);

    bf->priv->file_db = dbopen (filename, O_RDWR | O_CREAT, 0666, DB_HASH, NULL);

    if (bf->priv->file_db != NULL) {
        if (pas_backend_file_maybe_upgrade_db (bf))
            bf->priv->loaded = TRUE;
        /* XXX what if we fail to upgrade it? */
    }
    else
        g_warning ("pas_backend_file_load_uri failed for '%s'\n", filename);

    g_free (filename);
}

static void
pas_backend_file_add_client (PASBackend             *backend,
                 Evolution_BookListener  listener)
{
    PASBackendFile *bf;
    PASBook        *book;

    g_assert (backend != NULL);
    g_assert (PAS_IS_BACKEND_FILE (backend));

    bf = PAS_BACKEND_FILE (backend);

    book = pas_book_new (
        backend, listener,
        pas_backend_file_get_vcard);

    g_assert (book != NULL);

    gtk_signal_connect (GTK_OBJECT (book), "destroy",
            pas_backend_file_book_destroy_cb, NULL);

    gtk_signal_connect (GTK_OBJECT (book), "requests_queued",
            pas_backend_file_process_client_requests, NULL);

    bf->priv->clients = g_list_prepend (
        bf->priv->clients, book);

    if (bf->priv->loaded) {
        pas_book_respond_open (
            book, Evolution_BookListener_Success);
    } else {
        /* Open the book. */
        pas_book_respond_open (
            book, Evolution_BookListener_Success);
    }
}

static void
pas_backend_file_remove_client (PASBackend             *backend,
                PASBook                *book)
{
    g_return_if_fail (backend != NULL);
    g_return_if_fail (PAS_IS_BACKEND (backend));
    g_return_if_fail (book != NULL);
    g_return_if_fail (PAS_IS_BOOK (book));

    g_warning ("pas_backend_file_remove_client: Unimplemented!\n");
}

static gboolean
pas_backend_file_construct (PASBackendFile *backend)
{
    g_assert (backend != NULL);
    g_assert (PAS_IS_BACKEND_FILE (backend));

    if (! pas_backend_construct (PAS_BACKEND (backend)))
        return FALSE;

    return TRUE;
}

/**
 * pas_backend_file_new:
 */
PASBackend *
pas_backend_file_new (void)
{
    PASBackendFile *backend;

    backend = gtk_type_new (pas_backend_file_get_type ());

    if (! pas_backend_file_construct (backend)) {
        gtk_object_unref (GTK_OBJECT (backend));

        return NULL;
    }

    return PAS_BACKEND (backend);
}

static void
pas_backend_file_destroy (GtkObject *object)
{
    GTK_OBJECT_CLASS (pas_backend_file_parent_class)->destroy (object); 
}

static void
pas_backend_file_class_init (PASBackendFileClass *klass)
{
    GtkObjectClass  *object_class = (GtkObjectClass *) klass;
    PASBackendClass *parent_class;

    pas_backend_file_parent_class = gtk_type_class (pas_backend_get_type ());

    parent_class = PAS_BACKEND_CLASS (klass);

    /* Set the virtual methods. */
    parent_class->load_uri      = pas_backend_file_load_uri;
    parent_class->add_client    = pas_backend_file_add_client;
    parent_class->remove_client = pas_backend_file_remove_client;

    object_class->destroy = pas_backend_file_destroy;
}

static void
pas_backend_file_init (PASBackendFile *backend)
{
    PASBackendFilePrivate *priv;

    priv          = g_new0 (PASBackendFilePrivate, 1);
    priv->loaded  = FALSE;
    priv->clients = NULL;

    backend->priv = priv;
}

/**
 * pas_backend_file_get_type:
 */
GtkType
pas_backend_file_get_type (void)
{
    static GtkType type = 0;

    if (! type) {
        GtkTypeInfo info = {
            "PASBackendFile",
            sizeof (PASBackendFile),
            sizeof (PASBackendFileClass),
            (GtkClassInitFunc)  pas_backend_file_class_init,
            (GtkObjectInitFunc) pas_backend_file_init,
            NULL, /* reserved 1 */
            NULL, /* reserved 2 */
            (GtkClassInitFunc) NULL
        };

        type = gtk_type_unique (pas_backend_get_type (), &info);
    }

    return type;
}