/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 2017. All Rights Reserved.
*
* 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.
*
* %CopyrightEnd%
*/
/* This is a replacement for getenv(3) and friends, operating on instances so
* we can keep a common implementation for both the global and local (per-port)
* environments.
*
* The instances are not thread-safe on their own but unlike getenv(3) we're
* guaranteed to be the only user, so placing locks around all our accesses
* will suffice.
*
* Use erts_sys_rwlock_global_osenv to access the global environment. */
#ifndef __ERL_OSENV_H__
#define __ERL_OSENV_H__
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
typedef struct __erts_osenv_data_t erts_osenv_data_t;
typedef struct __erts_osenv_t {
struct __env_rbtnode_t *tree;
int variable_count;
int content_size;
} erts_osenv_t;
#include "sys.h"
struct __erts_osenv_data_t {
Sint length;
void *data;
};
void erts_osenv_init(erts_osenv_t *env);
void erts_osenv_clear(erts_osenv_t *env);
/* @brief Merges \c with into \c env
*
* @param overwrite Whether to overwrite existing entries or keep them as they
* are. */
void erts_osenv_merge(erts_osenv_t *env, const erts_osenv_t *with, int overwrite);
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* @brief Copies env[key] into \c value
*
* @return 1 on success, 0 if the key couldn't be found, and -1 if the input
* was invalid. */
int erts_osenv_get_term(const erts_osenv_t *env, struct process *process,
Eterm key, Eterm *value);
/* @brief Copies \c value into \c env[key]
*
* @return 1 on success, -1 if the input was invalid. */
int erts_osenv_put_term(erts_osenv_t *env, Eterm key, Eterm value);
/* @brief Removes \c env[key]
*
* @return 1 on success, 0 if the key couldn't be found, and -1 if the input
* was invalid. */
int erts_osenv_unset_term(erts_osenv_t *env, Eterm key);
/* @brief Copies env[key] into \c value
*
* @param value [in,out] The buffer to copy the value into, may be NULL if you
* only wish to query presence.
*
* @return 1 on success, 0 if the key couldn't be found, and -1 if if the value
* didn't fit into the buffer. */
int erts_osenv_get_native(const erts_osenv_t *env, const erts_osenv_data_t *key,
erts_osenv_data_t *value);
/* @brief Copies \c value into \c env[key]
*
* @return 1 on success, -1 on failure. */
int erts_osenv_put_native(erts_osenv_t *env, const erts_osenv_data_t *key,
const erts_osenv_data_t *value);
/* @brief Removes \c key from the env.
*
* @return 1 on success, 0 if the key couldn't be found. */
int erts_osenv_unset_native(erts_osenv_t *env, const erts_osenv_data_t *key);
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
typedef void (*erts_osenv_foreach_term_cb_t)(struct process *process,
void *state, Eterm key, Eterm value);
typedef void (*erts_osenv_foreach_native_cb_t)(void *state,
const erts_osenv_data_t *key,
const erts_osenv_data_t *value);
/* @brief Walks through all environment variables, calling \c callback for each
* one. It's unsafe to modify \c env within the callback. */
void erts_osenv_foreach_term(const erts_osenv_t *env, struct process *process,
void *state, erts_osenv_foreach_term_cb_t callback);
/* @copydoc erts_osenv_foreach_term */
void erts_osenv_foreach_native(const erts_osenv_t *env, void *state,
erts_osenv_foreach_native_cb_t callback);
#endif
