sendmail/libsmdb/smdb2.c

/*
** Copyright (c) 1999-2003, 2009 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: smdb2.c,v 8.80 2009/11/12 23:07:49 ca Exp $")

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


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

#if (DB_VERSION_MAJOR >= 2)

# define SMDB2_FILE_EXTENSION "db"

struct smdb_db2_database
{
    DB  *smdb2_db;
    int smdb2_lock_fd;
};
typedef struct smdb_db2_database SMDB_DB2_DATABASE;

/*
**  SMDB_TYPE_TO_DB2_TYPE -- Translates smdb database type to db2 type.
**
**  Parameters:
**      type -- The type to translate.
**
**  Returns:
**      The DB2 type that corresponsds to the passed in SMDB type.
**      Returns -1 if there is no equivalent type.
**
*/

DBTYPE
smdb_type_to_db2_type(type)
    SMDB_DBTYPE type;
{
    if (type == SMDB_TYPE_DEFAULT)
        return DB_HASH;

    if (strncmp(type, SMDB_TYPE_HASH, SMDB_TYPE_HASH_LEN) == 0)
        return DB_HASH;

    if (strncmp(type, SMDB_TYPE_BTREE, SMDB_TYPE_BTREE_LEN) == 0)
        return DB_BTREE;

    return DB_UNKNOWN;
}
/*
**  DB2_ERROR_TO_SMDB -- Translates db2 errors to smdbe errors
**
**  Parameters:
**      error -- The error to translate.
**
**  Returns:
**      The SMDBE error corresponding to the db2 error.
**      If we don't have a corresponding error, it returs errno.
**
*/

int
db2_error_to_smdb(error)
    int error;
{
    int result;

    switch (error)
    {
# ifdef DB_INCOMPLETE
        case DB_INCOMPLETE:
            result = SMDBE_INCOMPLETE;
            break;
# endif /* DB_INCOMPLETE */

# ifdef DB_NOTFOUND
        case DB_NOTFOUND:
            result = SMDBE_NOT_FOUND;
            break;
# endif /* DB_NOTFOUND */

# ifdef DB_KEYEMPTY
        case DB_KEYEMPTY:
            result = SMDBE_KEY_EMPTY;
            break;
# endif /* DB_KEYEMPTY */

# ifdef DB_KEYEXIST
        case DB_KEYEXIST:
            result = SMDBE_KEY_EXIST;
            break;
# endif /* DB_KEYEXIST */

# ifdef DB_LOCK_DEADLOCK
        case DB_LOCK_DEADLOCK:
            result = SMDBE_LOCK_DEADLOCK;
            break;
# endif /* DB_LOCK_DEADLOCK */

# ifdef DB_LOCK_NOTGRANTED
        case DB_LOCK_NOTGRANTED:
            result = SMDBE_LOCK_NOT_GRANTED;
            break;
# endif /* DB_LOCK_NOTGRANTED */

# ifdef DB_LOCK_NOTHELD
        case DB_LOCK_NOTHELD:
            result = SMDBE_LOCK_NOT_HELD;
            break;
# endif /* DB_LOCK_NOTHELD */

# ifdef DB_RUNRECOVERY
        case DB_RUNRECOVERY:
            result = SMDBE_RUN_RECOVERY;
            break;
# endif /* DB_RUNRECOVERY */

# ifdef DB_OLD_VERSION
        case DB_OLD_VERSION:
            result = SMDBE_OLD_VERSION;
            break;
# endif /* DB_OLD_VERSION */

        case 0:
            result = SMDBE_OK;
            break;

        default:
            result = error;
    }
    return result;
}
/*
**  SMDB_PUT_FLAGS_TO_DB2_FLAGS -- Translates smdb put flags to db2 put flags.
**
**  Parameters:
**      flags -- The flags to translate.
**
**  Returns:
**      The db2 flags that are equivalent to the smdb flags.
**
**  Notes:
**      Any invalid flags are ignored.
**
*/

unsigned int
smdb_put_flags_to_db2_flags(flags)
    SMDB_FLAG flags;
{
    int return_flags;

    return_flags = 0;

    if (bitset(SMDBF_NO_OVERWRITE, flags))
        return_flags |= DB_NOOVERWRITE;

    return return_flags;
}
/*
**  SMDB_CURSOR_GET_FLAGS_TO_DB2 -- Translates smdb cursor get flags to db2
**  getflags.
**
**  Parameters:
**      flags -- The flags to translate.
**
**  Returns:
**      The db2 flags that are equivalent to the smdb flags.
**
**  Notes:
**      -1 is returned if flag is unknown.
**
*/

int
smdb_cursor_get_flags_to_db2(flags)
    SMDB_FLAG flags;
{
    switch (flags)
    {
        case SMDB_CURSOR_GET_FIRST:
            return DB_FIRST;

        case SMDB_CURSOR_GET_LAST:
            return DB_LAST;

        case SMDB_CURSOR_GET_NEXT:
            return DB_NEXT;

        case SMDB_CURSOR_GET_RANGE:
            return DB_SET_RANGE;

        default:
            return -1;
    }
}

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

SMDB_DB2_DATABASE *
smdb2_malloc_database()
{
    SMDB_DB2_DATABASE *db2;

    db2 = (SMDB_DB2_DATABASE *) malloc(sizeof(SMDB_DB2_DATABASE));
    if (db2 != NULL)
        db2->smdb2_lock_fd = -1;

    return db2;
}

int
smdb2_close(database)
    SMDB_DATABASE *database;
{
    int result;
    SMDB_DB2_DATABASE *db2 = (SMDB_DB2_DATABASE *) database->smdb_impl;
    DB *db = ((SMDB_DB2_DATABASE *) database->smdb_impl)->smdb2_db;

    result = db2_error_to_smdb(db->close(db, 0));
    if (db2->smdb2_lock_fd != -1)
        close(db2->smdb2_lock_fd);

    free(db2);
    database->smdb_impl = NULL;

    return result;
}

int
smdb2_del(database, key, flags)
    SMDB_DATABASE *database;
    SMDB_DBENT *key;
    unsigned int flags;
{
    DB *db = ((SMDB_DB2_DATABASE *) database->smdb_impl)->smdb2_db;
    DBT dbkey;

    (void) memset(&dbkey, '\0', sizeof dbkey);
    dbkey.data = key->data;
    dbkey.size = key->size;
    return db2_error_to_smdb(db->del(db, NULL, &dbkey, flags));
}

int
smdb2_fd(database, fd)
    SMDB_DATABASE *database;
    int *fd;
{
    DB *db = ((SMDB_DB2_DATABASE *) database->smdb_impl)->smdb2_db;

    return db2_error_to_smdb(db->fd(db, fd));
}

int
smdb2_lockfd(database)
    SMDB_DATABASE *database;
{
    SMDB_DB2_DATABASE *db2 = (SMDB_DB2_DATABASE *) database->smdb_impl;

    return db2->smdb2_lock_fd;
}

int
smdb2_get(database, key, data, flags)
    SMDB_DATABASE *database;
    SMDB_DBENT *key;
    SMDB_DBENT *data;
    unsigned int flags;
{
    int result;
    DB *db = ((SMDB_DB2_DATABASE *) database->smdb_impl)->smdb2_db;
    DBT dbkey, dbdata;

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

    result = db->get(db, NULL, &dbkey, &dbdata, flags);
    data->data = dbdata.data;
    data->size = dbdata.size;
    return db2_error_to_smdb(result);
}

int
smdb2_put(database, key, data, flags)
    SMDB_DATABASE *database;
    SMDB_DBENT *key;
    SMDB_DBENT *data;
    unsigned int flags;
{
    DB *db = ((SMDB_DB2_DATABASE *) database->smdb_impl)->smdb2_db;
    DBT dbkey, dbdata;

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

    return db2_error_to_smdb(db->put(db, NULL, &dbkey, &dbdata,
                     smdb_put_flags_to_db2_flags(flags)));
}


int
smdb2_set_owner(database, uid, gid)
    SMDB_DATABASE *database;
    uid_t uid;
    gid_t gid;
{
# if HASFCHOWN
    int fd;
    int result;
    DB *db = ((SMDB_DB2_DATABASE *) database->smdb_impl)->smdb2_db;

    result = db->fd(db, &fd);
    if (result != 0)
        return result;

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

    return SMDBE_OK;
}

int
smdb2_sync(database, flags)
    SMDB_DATABASE *database;
    unsigned int flags;
{
    DB *db = ((SMDB_DB2_DATABASE *) database->smdb_impl)->smdb2_db;

    return db2_error_to_smdb(db->sync(db, flags));
}

int
smdb2_cursor_close(cursor)
    SMDB_CURSOR *cursor;
{
    int ret;
    DBC *dbc = (DBC *) cursor->smdbc_impl;

    ret = db2_error_to_smdb(dbc->c_close(dbc));
    free(cursor);
    return ret;
}

int
smdb2_cursor_del(cursor, flags)
    SMDB_CURSOR *cursor;
    SMDB_FLAG flags;
{
    DBC *dbc = (DBC *) cursor->smdbc_impl;

    return db2_error_to_smdb(dbc->c_del(dbc, 0));
}

int
smdb2_cursor_get(cursor, key, value, flags)
    SMDB_CURSOR *cursor;
    SMDB_DBENT *key;
    SMDB_DBENT *value;
    SMDB_FLAG flags;
{
    int db2_flags;
    int result;
    DBC *dbc = (DBC *) cursor->smdbc_impl;
    DBT dbkey, dbdata;

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

    db2_flags = smdb_cursor_get_flags_to_db2(flags);
    result = dbc->c_get(dbc, &dbkey, &dbdata, db2_flags);
    if (result == DB_NOTFOUND)
        return SMDBE_LAST_ENTRY;
    key->data = dbkey.data;
    key->size = dbkey.size;
    value->data = dbdata.data;
    value->size = dbdata.size;
    return db2_error_to_smdb(result);
}

int
smdb2_cursor_put(cursor, key, value, flags)
    SMDB_CURSOR *cursor;
    SMDB_DBENT *key;
    SMDB_DBENT *value;
    SMDB_FLAG flags;
{
    DBC *dbc = (DBC *) cursor->smdbc_impl;
    DBT dbkey, dbdata;

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

    return db2_error_to_smdb(dbc->c_put(dbc, &dbkey, &dbdata, 0));
}

int
smdb2_cursor(database, cursor, flags)
    SMDB_DATABASE *database;
    SMDB_CURSOR **cursor;
    SMDB_FLAG flags;
{
    int result;
    DB *db = ((SMDB_DB2_DATABASE *) database->smdb_impl)->smdb2_db;
    DBC *db2_cursor;

# if DB_VERSION_MAJOR > 2 || DB_VERSION_MINOR >= 6
    result = db->cursor(db, NULL, &db2_cursor, 0);
# else /* DB_VERSION_MAJOR > 2 || DB_VERSION_MINOR >= 6 */
    result = db->cursor(db, NULL, &db2_cursor);
# endif /* DB_VERSION_MAJOR > 2 || DB_VERSION_MINOR >= 6 */
    if (result != 0)
        return db2_error_to_smdb(result);

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

    (*cursor)->smdbc_close = smdb2_cursor_close;
    (*cursor)->smdbc_del = smdb2_cursor_del;
    (*cursor)->smdbc_get = smdb2_cursor_get;
    (*cursor)->smdbc_put = smdb2_cursor_put;
    (*cursor)->smdbc_impl = db2_cursor;

    return SMDBE_OK;
}

# if DB_VERSION_MAJOR == 2
static int
smdb_db_open_internal(db_name, db_type, db_flags, db_params, db)
    char *db_name;
    DBTYPE db_type;
    int db_flags;
    SMDB_DBPARAMS *db_params;
    DB **db;
{
    void *params;
    DB_INFO db_info;

    params = NULL;
    (void) memset(&db_info, '\0', sizeof db_info);
    if (db_params != NULL)
    {
        db_info.db_cachesize = db_params->smdbp_cache_size;
        if (db_type == DB_HASH)
            db_info.h_nelem = db_params->smdbp_num_elements;
        if (db_params->smdbp_allow_dup)
            db_info.flags |= DB_DUP;
        params = &db_info;
    }
    return db_open(db_name, db_type, db_flags, DBMMODE, NULL, params, db);
}
# endif /* DB_VERSION_MAJOR == 2 */

# if DB_VERSION_MAJOR > 2
static int
smdb_db_open_internal(db_name, db_type, db_flags, db_params, db)
    char *db_name;
    DBTYPE db_type;
    int db_flags;
    SMDB_DBPARAMS *db_params;
    DB **db;
{
    int result;

    result = db_create(db, NULL, 0);
    if (result != 0 || *db == NULL)
        return result;

    if (db_params != NULL)
    {
        result = (*db)->set_cachesize(*db, 0,
                          db_params->smdbp_cache_size, 0);
        if (result != 0)
        {
            (void) (*db)->close((*db), 0);
            *db = NULL;
            return db2_error_to_smdb(result);
        }
        if (db_type == DB_HASH)
        {
            result = (*db)->set_h_nelem(*db, db_params->smdbp_num_elements);
            if (result != 0)
            {
                (void) (*db)->close(*db, 0);
                *db = NULL;
                return db2_error_to_smdb(result);
            }
        }
        if (db_params->smdbp_allow_dup)
        {
            result = (*db)->set_flags(*db, DB_DUP);
            if (result != 0)
            {
                (void) (*db)->close(*db, 0);
                *db = NULL;
                return db2_error_to_smdb(result);
            }
        }
    }

    result = (*db)->open(*db,
                 DBTXN  /* transaction for DB 4.1 */
                 db_name, NULL, db_type, db_flags, DBMMODE);
    if (result != 0)
    {
        (void) (*db)->close(*db, 0);
        *db = NULL;
    }
    return db2_error_to_smdb(result);
}
# endif /* DB_VERSION_MAJOR > 2 */
/*
**  SMDB_DB_OPEN -- Opens a db database.
**
**  Parameters:
**      database -- An unallocated database pointer to a pointer.
**      db_name -- The name of the database without extension.
**      mode -- File permisions for a created database.
**      mode_mask -- Mode bits that must match on an opened database.
**      sff -- Flags for safefile.
**      type -- The type of database to open
**          See smdb_type_to_db2_type for valid types.
**      user_info -- User information for file permissions.
**      db_params --
**          An SMDB_DBPARAMS struct including params. These
**          are processed according to the type of the
**          database. Currently supported params (only for
**          HASH type) are:
**             num_elements
**             cache_size
**
**  Returns:
**      SMDBE_OK -- Success, other errno:
**      SMDBE_MALLOC -- Cannot allocate memory.
**      SMDBE_BAD_OPEN -- db_open didn't return an error, but
**               somehow the DB pointer is NULL.
**      Anything else: translated error from db2
*/

int
smdb_db_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 db_flags;
    int lock_fd;
    int db_fd;
    int major_v, minor_v, patch_v;
    SMDB_DATABASE *smdb_db;
    SMDB_DB2_DATABASE *db2;
    DB *db;
    DBTYPE db_type;
    struct stat stat_info;
    char db_file_name[MAXPATHLEN];

    (void) db_version(&major_v, &minor_v, &patch_v);
    if (major_v != DB_VERSION_MAJOR || minor_v != DB_VERSION_MINOR)
        return SMDBE_VERSION_MISMATCH;

    *database = NULL;

    result = smdb_add_extension(db_file_name, sizeof db_file_name,
                    db_name, SMDB2_FILE_EXTENSION);
    if (result != SMDBE_OK)
        return result;

    result = smdb_setup_file(db_name, SMDB2_FILE_EXTENSION,
                 mode_mask, sff, user_info, &stat_info);
    if (result != SMDBE_OK)
        return result;

    lock_fd = -1;

    if (stat_info.st_mode == ST_MODE_NOFILE &&
        bitset(mode, O_CREAT))
        lockcreated = true;

    result = smdb_lock_file(&lock_fd, db_name, mode, sff,
                SMDB2_FILE_EXTENSION);
    if (result != SMDBE_OK)
        return result;

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

    smdb_db = smdb_malloc_database();
    db2 = smdb2_malloc_database();
    if (db2 == NULL || smdb_db == NULL)
    {
        smdb_unlock_file(lock_fd);
        smdb_free_database(smdb_db);    /* ok to be NULL */
        return SMDBE_MALLOC;
    }

    db2->smdb2_lock_fd = lock_fd;

    db_type = smdb_type_to_db2_type(type);

    db = NULL;

    db_flags = 0;
    if (bitset(O_CREAT, mode))
        db_flags |= DB_CREATE;
    if (bitset(O_TRUNC, mode))
        db_flags |= DB_TRUNCATE;
    if (mode == O_RDONLY)
        db_flags |= DB_RDONLY;
    SM_DB_FLAG_ADD(db_flags);

    result = smdb_db_open_internal(db_file_name, db_type,
                       db_flags, db_params, &db);

    if (result == 0 && db != NULL)
    {
        result = db->fd(db, &db_fd);
        if (result == 0)
            result = SMDBE_OK;
    }
    else
    {
        /* Try and narrow down on the problem */
        if (result != 0)
            result = db2_error_to_smdb(result);
        else
            result = SMDBE_BAD_OPEN;
    }

    if (result == SMDBE_OK)
        result = smdb_filechanged(db_name, SMDB2_FILE_EXTENSION, db_fd,
                      &stat_info);

    if (result == SMDBE_OK)
    {
        /* Everything is ok. Setup driver */
        db2->smdb2_db = db;

        smdb_db->smdb_close = smdb2_close;
        smdb_db->smdb_del = smdb2_del;
        smdb_db->smdb_fd = smdb2_fd;
        smdb_db->smdb_lockfd = smdb2_lockfd;
        smdb_db->smdb_get = smdb2_get;
        smdb_db->smdb_put = smdb2_put;
        smdb_db->smdb_set_owner = smdb2_set_owner;
        smdb_db->smdb_sync = smdb2_sync;
        smdb_db->smdb_cursor = smdb2_cursor;
        smdb_db->smdb_impl = db2;

        *database = smdb_db;

        return SMDBE_OK;
    }

    if (db != NULL)
        db->close(db, 0);

    smdb_unlock_file(db2->smdb2_lock_fd);
    free(db2);
    smdb_free_database(smdb_db);

    return result;
}

#endif /* (DB_VERSION_MAJOR >= 2) */