/* 
 *------------------------------------------------------------------
 * svmdb.h - shared VM database
 *
 * Copyright (c) 2009 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *------------------------------------------------------------------
 */

#ifndef __included_svmdb_h__
#define __included_svmdb_h__

#include "svm.h"

typedef enum  {
    SVMDB_ACTION_ILLEGAL=0,
    SVMDB_ACTION_GET,           /* not clear why anyone would care */
    SVMDB_ACTION_SET,
    SVMDB_ACTION_UNSET,
} svmdb_action_t;

typedef struct {
    int pid;
    int signum;
    u32 action:4;
    u32 opaque:28;
} svmdb_notify_t;

typedef struct {
    u8 *value;
    svmdb_notify_t *notifications;
    u32 elsize;
} svmdb_value_t;

typedef enum {
    SVMDB_NAMESPACE_STRING=0,
    SVMDB_NAMESPACE_VEC,
    SVMDB_N_NAMESPACES,
} svmdb_namespace_t;

typedef struct {
    uword version;
    /* pool of values */
    svmdb_value_t *values;
    uword *namespaces [SVMDB_N_NAMESPACES];
} svmdb_shm_hdr_t;

#define SVMDB_SHM_VERSION 2

typedef struct {
    int flags;
    int pid;
    svm_region_t *db_rp;
    svmdb_shm_hdr_t *shm;
} svmdb_client_t;    

typedef struct {
    int add_del;
    svmdb_namespace_t nspace;
    char *var;
    u32 elsize;
    int signum;
    u32 action:4;
    u32 opaque:28;
} svmdb_notification_args_t;

/* 
 * Must be a reasonable number, several mb smaller than 
 * SVM_GLOBAL_REGION_SIZE, or no donut for you...
 */
#define SVMDB_DEFAULT_SIZE (4<<20)

svmdb_client_t *svmdb_map (void);

svmdb_client_t *svmdb_map_size (uword size);

svmdb_client_t *svmdb_map_chroot (char *root_path);

svmdb_client_t *svmdb_map_chroot_size (char *root_path, uword size);

void svmdb_unmap (svmdb_client_t *client);
void svmdb_local_unset_string_variable (svmdb_client_t *client, char *var);
void svmdb_local_set_string_variable (svmdb_client_t *client, 
                                      char *var, char *val);
char *svmdb_local_get_string_variable (svmdb_client_t *client, char *var);
void *svmdb_local_get_variable_reference (svmdb_client_t *client,
                                          svmdb_namespace_t ns,
                                          char *var);

void svmdb_local_dump_strings (svmdb_client_t *client);

void svmdb_local_unset_vec_variable (svmdb_client_t *client, char *var);
void svmdb_local_set_vec_variable (svmdb_client_t *client, 
                                      char *var, void *val, u32 elsize);
void *svmdb_local_get_vec_variable (svmdb_client_t *client, char *var, 
                                    u32 elsize);
void svmdb_local_dump_vecs (svmdb_client_t *client);

int svmdb_local_add_del_notification (svmdb_client_t *client, 
                                      svmdb_notification_args_t *args);

void *svmdb_local_find_or_add_vec_variable (svmdb_client_t *client, 
                                            char *var, u32 nbytes);

#endif /* __included_svmdb_h__ */