/*
** Copyright (c) 1999-2002 Sendmail, Inc. and its suppliers.
**      All rights reserved.
**
** By using this file, you agree to the terms and conditions set
** forth in the LICENSE file which can be found at the top level of
** the sendmail distribution.
*/

#include <sm/gen.h>
SM_RCSID("@(#)$Id: smndbm.c,v 8.52 2002/05/21 22:30:30 gshapiro Exp $")

#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>

#include <sendmail/sendmail.h>
#include <libsmdb/smdb.h>

#ifdef NDBM

# define SMNDB_DIR_FILE_EXTENSION "dir"
# define SMNDB_PAG_FILE_EXTENSION "pag"

struct smdb_dbm_database_struct
{
        DBM     *smndbm_dbm;
        int     smndbm_lock_fd;
        bool    smndbm_cursor_in_use;
};
typedef struct smdb_dbm_database_struct SMDB_DBM_DATABASE;

struct smdb_dbm_cursor_struct
{
        SMDB_DBM_DATABASE       *smndbmc_db;
        datum                   smndbmc_current_key;
};
typedef struct smdb_dbm_cursor_struct SMDB_DBM_CURSOR;

/*
**  SMDB_PUT_FLAGS_TO_NDBM_FLAGS -- Translates smdb put flags to ndbm put flags.
**
**      Parameters:
**              flags -- The flags to translate.
**
**      Returns:
**              The ndbm flags that are equivalent to the smdb flags.
**
**      Notes:
**              Any invalid flags are ignored.
**
*/

int
smdb_put_flags_to_ndbm_flags(flags)
        SMDB_FLAG flags;
{
        int return_flags;

        return_flags = 0;
        if (bitset(SMDBF_NO_OVERWRITE, flags))
                return_flags = DBM_INSERT;
        else
                return_flags = DBM_REPLACE;

        return return_flags;
}

/*
**  Except for smdb_ndbm_open, the rest of these function correspond to the
**  interface laid out in smdb.h.
*/

SMDB_DBM_DATABASE *
smdbm_malloc_database()
{
        SMDB_DBM_DATABASE *db;

        db = (SMDB_DBM_DATABASE *) malloc(sizeof(SMDB_DBM_DATABASE));
        if (db != NULL)
        {
                db->smndbm_dbm = NULL;
                db->smndbm_lock_fd = -1;
                db->smndbm_cursor_in_use = false;
        }

        return db;
}

int
smdbm_close(database)
        SMDB_DATABASE *database;
{
        SMDB_DBM_DATABASE *db = (SMDB_DBM_DATABASE *) database->smdb_impl;
        DBM *dbm = ((SMDB_DBM_DATABASE *) database->smdb_impl)->smndbm_dbm;

        dbm_close(dbm);
        if (db->smndbm_lock_fd != -1)
                close(db->smndbm_lock_fd);

        free(db);
        database->smdb_impl = NULL;

        return SMDBE_OK;
}

int
smdbm_del(database, key, flags)
        SMDB_DATABASE *database;
        SMDB_DBENT *key;
        unsigned int flags;
{
        int result;
        DBM *dbm = ((SMDB_DBM_DATABASE *) database->smdb_impl)->smndbm_dbm;
        datum dbkey;

        (void) memset(&dbkey, '\0', sizeof dbkey);
        dbkey.dptr = key->data;
        dbkey.dsize = key->size;

        errno = 0;
        result = dbm_delete(dbm, dbkey);
        if (result != 0)
        {
                int save_errno = errno;

                if (dbm_error(dbm))
                        return SMDBE_IO_ERROR;

                if (save_errno != 0)
                        return save_errno;

                return SMDBE_NOT_FOUND;
        }
        return SMDBE_OK;
}

int
smdbm_fd(database, fd)
        SMDB_DATABASE *database;
        int *fd;
{
        DBM *dbm = ((SMDB_DBM_DATABASE *) database->smdb_impl)->smndbm_dbm;

        *fd = dbm_dirfno(dbm);
        if (*fd <= 0)
                return EINVAL;

        return SMDBE_OK;
}

int
smdbm_lockfd(database)
        SMDB_DATABASE *database;
{
        SMDB_DBM_DATABASE *db = (SMDB_DBM_DATABASE *) database->smdb_impl;

        return db->smndbm_lock_fd;
}

int
smdbm_get(database, key, data, flags)
        SMDB_DATABASE *database;
        SMDB_DBENT *key;
        SMDB_DBENT *data;
        unsigned int flags;
{
        DBM *dbm = ((SMDB_DBM_DATABASE *) database->smdb_impl)->smndbm_dbm;
        datum dbkey, dbdata;

        (void) memset(&dbkey, '\0', sizeof dbkey);
        (void) memset(&dbdata, '\0', sizeof dbdata);
        dbkey.dptr = key->data;
        dbkey.dsize = key->size;

        errno = 0;
        dbdata = dbm_fetch(dbm, dbkey);
        if (dbdata.dptr == NULL)
        {
                int save_errno = errno;

                if (dbm_error(dbm))
                        return SMDBE_IO_ERROR;

                if (save_errno != 0)
                        return save_errno;

                return SMDBE_NOT_FOUND;
        }
        data->data = dbdata.dptr;
        data->size = dbdata.dsize;
        return SMDBE_OK;
}

int
smdbm_put(database, key, data, flags)
        SMDB_DATABASE *database;
        SMDB_DBENT *key;
        SMDB_DBENT *data;
        unsigned int flags;
{
        int result;
        int save_errno;
        DBM *dbm = ((SMDB_DBM_DATABASE *) database->smdb_impl)->smndbm_dbm;
        datum dbkey, dbdata;

        (void) memset(&dbkey, '\0', sizeof dbkey);
        (void) memset(&dbdata, '\0', sizeof dbdata);
        dbkey.dptr = key->data;
        dbkey.dsize = key->size;
        dbdata.dptr = data->data;
        dbdata.dsize = data->size;

        errno = 0;
        result = dbm_store(dbm, dbkey, dbdata,
                           smdb_put_flags_to_ndbm_flags(flags));
        switch (result)
        {
          case 1:
                return SMDBE_DUPLICATE;

          case 0:
                return SMDBE_OK;

          default:
                save_errno = errno;

                if (dbm_error(dbm))
                        return SMDBE_IO_ERROR;

                if (save_errno != 0)
                        return save_errno;

                return SMDBE_IO_ERROR;
        }
        /* NOTREACHED */
}

int
smndbm_set_owner(database, uid, gid)
        SMDB_DATABASE *database;
        uid_t uid;
        gid_t gid;
{
# if HASFCHOWN
        int fd;
        int result;
        DBM *dbm = ((SMDB_DBM_DATABASE *) database->smdb_impl)->smndbm_dbm;

        fd = dbm_dirfno(dbm);
        if (fd <= 0)
                return EINVAL;

        result = fchown(fd, uid, gid);
        if (result < 0)
                return errno;

        fd = dbm_pagfno(dbm);
        if (fd <= 0)
                return EINVAL;

        result = fchown(fd, uid, gid);
        if (result < 0)
                return errno;
# endif /* HASFCHOWN */

        return SMDBE_OK;
}

int
smdbm_sync(database, flags)
        SMDB_DATABASE *database;
        unsigned int flags;
{
        return SMDBE_UNSUPPORTED;
}

int
smdbm_cursor_close(cursor)
        SMDB_CURSOR *cursor;
{
        SMDB_DBM_CURSOR *dbm_cursor = (SMDB_DBM_CURSOR *) cursor->smdbc_impl;
        SMDB_DBM_DATABASE *db = dbm_cursor->smndbmc_db;

        if (!db->smndbm_cursor_in_use)
                return SMDBE_NOT_A_VALID_CURSOR;

        db->smndbm_cursor_in_use = false;
        free(dbm_cursor);
        free(cursor);

        return SMDBE_OK;
}

int
smdbm_cursor_del(cursor, flags)
        SMDB_CURSOR *cursor;
        unsigned int flags;
{
        int result;
        SMDB_DBM_CURSOR *dbm_cursor = (SMDB_DBM_CURSOR *) cursor->smdbc_impl;
        SMDB_DBM_DATABASE *db = dbm_cursor->smndbmc_db;
        DBM *dbm = db->smndbm_dbm;

        errno = 0;
        result = dbm_delete(dbm, dbm_cursor->smndbmc_current_key);
        if (result != 0)
        {
                int save_errno = errno;

                if (dbm_error(dbm))
                        return SMDBE_IO_ERROR;

                if (save_errno != 0)
                        return save_errno;

                return SMDBE_NOT_FOUND;
        }
        return SMDBE_OK;
}

int
smdbm_cursor_get(cursor, key, value, flags)
        SMDB_CURSOR *cursor;
        SMDB_DBENT *key;
        SMDB_DBENT *value;
        SMDB_FLAG flags;
{
        SMDB_DBM_CURSOR *dbm_cursor = (SMDB_DBM_CURSOR *) cursor->smdbc_impl;
        SMDB_DBM_DATABASE *db = dbm_cursor->smndbmc_db;
        DBM *dbm = db->smndbm_dbm;
        datum dbkey, dbdata;

        (void) memset(&dbkey, '\0', sizeof dbkey);
        (void) memset(&dbdata, '\0', sizeof dbdata);

        if (flags == SMDB_CURSOR_GET_RANGE)
                return SMDBE_UNSUPPORTED;

        if (dbm_cursor->smndbmc_current_key.dptr == NULL)
        {
                dbm_cursor->smndbmc_current_key = dbm_firstkey(dbm);
                if (dbm_cursor->smndbmc_current_key.dptr == NULL)
                {
                        if (dbm_error(dbm))
                                return SMDBE_IO_ERROR;
                        return SMDBE_LAST_ENTRY;
                }
        }
        else
        {
                dbm_cursor->smndbmc_current_key = dbm_nextkey(dbm);
                if (dbm_cursor->smndbmc_current_key.dptr == NULL)
                {
                        if (dbm_error(dbm))
                                return SMDBE_IO_ERROR;
                        return SMDBE_LAST_ENTRY;
                }
        }

        errno = 0;
        dbdata = dbm_fetch(dbm, dbm_cursor->smndbmc_current_key);
        if (dbdata.dptr == NULL)
        {
                int save_errno = errno;

                if (dbm_error(dbm))
                        return SMDBE_IO_ERROR;

                if (save_errno != 0)
                        return save_errno;

                return SMDBE_NOT_FOUND;
        }
        value->data = dbdata.dptr;
        value->size = dbdata.dsize;
        key->data = dbm_cursor->smndbmc_current_key.dptr;
        key->size = dbm_cursor->smndbmc_current_key.dsize;

        return SMDBE_OK;
}

int
smdbm_cursor_put(cursor, key, value, flags)
        SMDB_CURSOR *cursor;
        SMDB_DBENT *key;
        SMDB_DBENT *value;
        SMDB_FLAG flags;
{
        int result;
        int save_errno;
        SMDB_DBM_CURSOR *dbm_cursor = (SMDB_DBM_CURSOR *) cursor->smdbc_impl;
        SMDB_DBM_DATABASE *db = dbm_cursor->smndbmc_db;
        DBM *dbm = db->smndbm_dbm;
        datum dbdata;

        (void) memset(&dbdata, '\0', sizeof dbdata);
        dbdata.dptr = value->data;
        dbdata.dsize = value->size;

        errno = 0;
        result = dbm_store(dbm, dbm_cursor->smndbmc_current_key, dbdata,
                           smdb_put_flags_to_ndbm_flags(flags));
        switch (result)
        {
          case 1:
                return SMDBE_DUPLICATE;

          case 0:
                return SMDBE_OK;

          default:
                save_errno = errno;

                if (dbm_error(dbm))
                        return SMDBE_IO_ERROR;

                if (save_errno != 0)
                        return save_errno;

                return SMDBE_IO_ERROR;
        }
        /* NOTREACHED */
}

int
smdbm_cursor(database, cursor, flags)
        SMDB_DATABASE *database;
        SMDB_CURSOR **cursor;
        SMDB_FLAG flags;
{
        SMDB_DBM_DATABASE *db = (SMDB_DBM_DATABASE *) database->smdb_impl;
        SMDB_CURSOR *cur;
        SMDB_DBM_CURSOR *dbm_cursor;

        if (db->smndbm_cursor_in_use)
                return SMDBE_ONLY_SUPPORTS_ONE_CURSOR;

        db->smndbm_cursor_in_use = true;
        dbm_cursor = (SMDB_DBM_CURSOR *) malloc(sizeof(SMDB_DBM_CURSOR));
        dbm_cursor->smndbmc_db = db;
        dbm_cursor->smndbmc_current_key.dptr = NULL;
        dbm_cursor->smndbmc_current_key.dsize = 0;

        cur = (SMDB_CURSOR*) malloc(sizeof(SMDB_CURSOR));
        if (cur == NULL)
                return SMDBE_MALLOC;

        cur->smdbc_impl = dbm_cursor;
        cur->smdbc_close = smdbm_cursor_close;
        cur->smdbc_del = smdbm_cursor_del;
        cur->smdbc_get = smdbm_cursor_get;
        cur->smdbc_put = smdbm_cursor_put;
        *cursor = cur;

        return SMDBE_OK;
}
/*
**  SMDB_NDBM_OPEN -- Opens a ndbm database.
**
**      Parameters:
**              database -- An unallocated database pointer to a pointer.
**              db_name -- The name of the database without extension.
**              mode -- File permisions on a created database.
**              mode_mask -- Mode bits that much match on an opened database.
**              sff -- Flags to safefile.
**              type -- The type of database to open.
**                      Only SMDB_NDBM is supported.
**              user_info -- Information on the user to use for file
**                          permissions.
**              db_params -- No params are supported.
**
**      Returns:
**              SMDBE_OK -- Success, otherwise errno:
**              SMDBE_MALLOC -- Cannot allocate memory.
**              SMDBE_UNSUPPORTED -- The type is not supported.
**              SMDBE_GDBM_IS_BAD -- We have detected GDBM and we don't
**                                  like it.
**              SMDBE_BAD_OPEN -- dbm_open failed and errno was not set.
**              Anything else: errno
*/

int
smdb_ndbm_open(database, db_name, mode, mode_mask, sff, type, user_info,
               db_params)
        SMDB_DATABASE **database;
        char *db_name;
        int mode;
        int mode_mask;
        long sff;
        SMDB_DBTYPE type;
        SMDB_USER_INFO *user_info;
        SMDB_DBPARAMS *db_params;
{
        bool lockcreated = false;
        int result;
        int lock_fd;
        SMDB_DATABASE *smdb_db;
        SMDB_DBM_DATABASE *db;
        DBM *dbm = NULL;
        struct stat dir_stat_info;
        struct stat pag_stat_info;

        result = SMDBE_OK;
        *database = NULL;

        if (type == NULL)
                return SMDBE_UNKNOWN_DB_TYPE;

        result = smdb_setup_file(db_name, SMNDB_DIR_FILE_EXTENSION, mode_mask,
                                 sff, user_info, &dir_stat_info);
        if (result != SMDBE_OK)
                return result;

        result = smdb_setup_file(db_name, SMNDB_PAG_FILE_EXTENSION, mode_mask,
                                 sff, user_info, &pag_stat_info);
        if (result != SMDBE_OK)
                return result;

        if ((dir_stat_info.st_mode == ST_MODE_NOFILE ||
             pag_stat_info.st_mode == ST_MODE_NOFILE) &&
            bitset(mode, O_CREAT))
                lockcreated = true;

        lock_fd = -1;
        result = smdb_lock_file(&lock_fd, db_name, mode, sff,
                                SMNDB_DIR_FILE_EXTENSION);
        if (result != SMDBE_OK)
                return result;

        if (lockcreated)
        {
                int pag_fd;

                /* Need to pre-open the .pag file as well with O_EXCL */
                result = smdb_lock_file(&pag_fd, db_name, mode, sff,
                                        SMNDB_PAG_FILE_EXTENSION);
                if (result != SMDBE_OK)
                {
                        (void) close(lock_fd);
                        return result;
                }
                (void) close(pag_fd);

                mode |= O_TRUNC;
                mode &= ~(O_CREAT|O_EXCL);
        }

        smdb_db = smdb_malloc_database();
        if (smdb_db == NULL)
                result = SMDBE_MALLOC;

        db = smdbm_malloc_database();
        if (db == NULL)
                result = SMDBE_MALLOC;

        /* Try to open database */
        if (result == SMDBE_OK)
        {
                db->smndbm_lock_fd = lock_fd;

                errno = 0;
                dbm = dbm_open(db_name, mode, DBMMODE);
                if (dbm == NULL)
                {
                        if (errno == 0)
                                result = SMDBE_BAD_OPEN;
                        else
                                result = errno;
                }
                db->smndbm_dbm = dbm;
        }

        /* Check for GDBM */
        if (result == SMDBE_OK)
        {
                if (dbm_dirfno(dbm) == dbm_pagfno(dbm))
                        result = SMDBE_GDBM_IS_BAD;
        }

        /* Check for filechanged */
        if (result == SMDBE_OK)
        {
                result = smdb_filechanged(db_name, SMNDB_DIR_FILE_EXTENSION,
                                          dbm_dirfno(dbm), &dir_stat_info);
                if (result == SMDBE_OK)
                {
                        result = smdb_filechanged(db_name,
                                                  SMNDB_PAG_FILE_EXTENSION,
                                                  dbm_pagfno(dbm),
                                                  &pag_stat_info);
                }
        }

        /* XXX Got to get fchown stuff in here */

        /* Setup driver if everything is ok */
        if (result == SMDBE_OK)
        {
                *database = smdb_db;

                smdb_db->smdb_close = smdbm_close;
                smdb_db->smdb_del = smdbm_del;
                smdb_db->smdb_fd = smdbm_fd;
                smdb_db->smdb_lockfd = smdbm_lockfd;
                smdb_db->smdb_get = smdbm_get;
                smdb_db->smdb_put = smdbm_put;
                smdb_db->smdb_set_owner = smndbm_set_owner;
                smdb_db->smdb_sync = smdbm_sync;
                smdb_db->smdb_cursor = smdbm_cursor;

                smdb_db->smdb_impl = db;

                return SMDBE_OK;
        }

        /* If we're here, something bad happened, clean up */
        if (dbm != NULL)
                dbm_close(dbm);

        smdb_unlock_file(db->smndbm_lock_fd);
        free(db);
        smdb_free_database(smdb_db);

        return result;
}
#endif /* NDBM */