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/**
* @file
*
* @brief Instantiate a Private User Environment
* @ingroup LibIOEnv
*/
/*
* Submitted by: fernando.ruiz@ctv.es (correo@fernando-ruiz.com)
*
* COPYRIGHT (c) 1989-2010.
* On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdlib.h>
#include <rtems/libio_.h>
#include <rtems/score/threaddispatch.h>
/**
* Instantiate a private user environment for the calling thread.
*/
static void free_user_env(void *arg)
{
rtems_user_env_t *env = arg;
bool uses_global_env = env == &rtems_global_user_env;
if (!uses_global_env) {
if (env->reference_count == 1) {
rtems_filesystem_global_location_release(env->current_directory);
rtems_filesystem_global_location_release(env->root_directory);
free(env);
} else {
--env->reference_count;
}
}
}
static void free_user_env_protected(rtems_user_env_t *env)
{
_Thread_Disable_dispatch();
free_user_env(env);
_Thread_Enable_dispatch();
}
rtems_status_code rtems_libio_set_private_env(void)
{
rtems_status_code sc = RTEMS_SUCCESSFUL;
rtems_id self_task_id = rtems_task_self();
rtems_user_env_t *old_env = rtems_current_user_env;
bool uses_global_env = old_env == &rtems_global_user_env;
bool uses_shared_env = old_env->task_id != self_task_id;
if (uses_global_env || uses_shared_env) {
rtems_user_env_t *new_env = calloc(1, sizeof(*new_env));
if (new_env != NULL) {
*new_env = *old_env;
new_env->reference_count = 1;
new_env->task_id = self_task_id;
new_env->root_directory =
rtems_filesystem_global_location_obtain(&old_env->root_directory);
new_env->current_directory =
rtems_filesystem_global_location_obtain(&old_env->current_directory);
if (
!rtems_filesystem_global_location_is_null(new_env->root_directory)
&& !rtems_filesystem_global_location_is_null(new_env->current_directory)
) {
sc = rtems_task_variable_add(
RTEMS_SELF,
(void **) &rtems_current_user_env,
free_user_env
);
if (sc == RTEMS_SUCCESSFUL) {
free_user_env_protected(old_env);
rtems_current_user_env = new_env;
} else {
sc = RTEMS_TOO_MANY;
}
} else {
sc = RTEMS_UNSATISFIED;
}
if (sc != RTEMS_SUCCESSFUL) {
free_user_env(new_env);
}
} else {
sc = RTEMS_NO_MEMORY;
}
}
return sc;
}
rtems_status_code rtems_libio_share_private_env(rtems_id task_id)
{
rtems_status_code sc = RTEMS_SUCCESSFUL;
rtems_id self_task_id = rtems_task_self();
if (task_id != RTEMS_SELF && self_task_id != task_id) {
rtems_user_env_t *env;
/*
* We have to disable the thread dispatching to prevent deletion of the
* environment in the meantime.
*/
_Thread_Disable_dispatch();
sc = rtems_task_variable_get(
task_id,
(void *) &rtems_current_user_env,
(void *) &env
);
if (sc == RTEMS_SUCCESSFUL) {
++env->reference_count;
} else {
sc = RTEMS_UNSATISFIED;
}
_Thread_Enable_dispatch();
if (sc == RTEMS_SUCCESSFUL) {
sc = rtems_task_variable_add(
RTEMS_SELF,
(void **) &rtems_current_user_env,
free_user_env
);
if (sc == RTEMS_SUCCESSFUL) {
free_user_env_protected(rtems_current_user_env);
rtems_current_user_env = env;
} else {
free_user_env_protected(env);
sc = RTEMS_TOO_MANY;
}
}
}
return sc;
}
void rtems_libio_use_global_env(void)
{
rtems_status_code sc = RTEMS_SUCCESSFUL;
rtems_user_env_t *env = rtems_current_user_env;
bool uses_private_env = env != &rtems_global_user_env;
if (uses_private_env) {
sc = rtems_task_variable_delete(
RTEMS_SELF,
(void **) &rtems_current_user_env
);
if (sc != RTEMS_SUCCESSFUL) {
rtems_fatal_error_occurred(0xdeadbeef);
}
rtems_current_user_env = &rtems_global_user_env;
}
}
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