* libs/libc/elf/elf_registry.c
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you 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.
*
****************************************************************************/
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <string.h>
#include <assert.h>
#include <debug.h>
#include <errno.h>
#include <nuttx/mutex.h>
#include <nuttx/lib/elf.h>
* Pre-processor Definitions
****************************************************************************/
* Private Types
****************************************************************************/
* Private Data
****************************************************************************/
static rmutex_t g_modlock = NXRMUTEX_INITIALIZER;
static FAR struct module_s *g_mod_registry;
* Public Functions
****************************************************************************/
* Name: libelf_registry_lock
*
* Description:
* Get exclusive access to the module registry.
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
void libelf_registry_lock(void)
{
nxrmutex_lock(&g_modlock);
}
* Name: libelf_registry_unlock
*
* Description:
* Relinquish the lock on the module registry
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
void libelf_registry_unlock(void)
{
nxrmutex_unlock(&g_modlock);
}
* Name: libelf_registry_add
*
* Description:
* Add a new entry to the module registry.
*
* Input Parameters:
* modp - The module data structure to be registered.
*
* Returned Value:
* None
*
* Assumptions:
* The caller holds the lock on the module registry.
*
****************************************************************************/
void libelf_registry_add(FAR struct module_s *modp)
{
DEBUGASSERT(modp);
modp->flink = g_mod_registry;
g_mod_registry = modp;
}
* Name: libelf_registry_del
*
* Description:
* Remove a module entry from the registry
*
* Input Parameters:
* modp - The registry entry to be removed.
*
* Returned Value:
* Zero (OK) is returned if the registry entry was deleted. Otherwise,
* a negated errno value is returned.
*
* Assumptions:
* The caller holds the lock on the module registry.
*
****************************************************************************/
int libelf_registry_del(FAR struct module_s *modp)
{
FAR struct module_s *prev;
FAR struct module_s *curr;
for (prev = NULL, curr = g_mod_registry;
curr != NULL && curr != modp;
prev = curr, curr = curr->flink);
if (curr == NULL)
{
berr("ERROR: Could not find module entry\n");
return -ENOENT;
}
if (prev == NULL)
{
g_mod_registry = modp->flink;
}
else
{
prev->flink = modp->flink;
}
modp->flink = NULL;
return OK;
}
* Name: libelf_registry_find
*
* Description:
* Find an entry in the module registry using the name of the module.
*
* Input Parameters:
* modname - The name of the module to be found
*
* Returned Value:
* If the registry entry is found, a pointer to the module entry is
* returned. NULL is returned if the entry is not found.
*
* Assumptions:
* The caller holds the lock on the module registry.
*
****************************************************************************/
#ifdef HAVE_LIBC_ELF_NAMES
FAR struct module_s *libelf_registry_find(FAR const char *modname)
{
FAR struct module_s *modp;
for (modp = g_mod_registry;
modp != NULL &&
strncmp(modp->modname, modname, LIBC_ELF_NAMEMAX) != 0;
modp = modp->flink);
return modp;
}
#endif
* Name: libelf_registry_verify
*
* Description:
* Verify that a module handle is valid by traversing the module list and
* assuring that the module still resides in the list. If it does not,
* the handle is probably a stale pointer.
*
* Input Parameters:
* modp - The registry entry to be verified.
*
* Returned Value:
* Returns OK is the module is valid; -ENOENT otherwise.
*
* Assumptions:
* The caller holds the lock on the module registry.
*
****************************************************************************/
int libelf_registry_verify(FAR struct module_s *modp)
{
FAR struct module_s *node;
for (node = g_mod_registry; node != NULL; node = node->flink)
{
if (node == modp)
{
return OK;
}
}
return -ENOENT;
}
* Name: libelf_registry_foreach
*
* Description:
* Visit each module in the registry
*
* Input Parameters:
* callback - This callback function was be called for each entry in the
* registry.
* arg - This opaque argument will be passed to the callback function.
*
* Returned Value:
* This function normally returns zero (OK). If, however, any callback
* function returns a non-zero value, the traversal will be terminated and
* that non-zero value will be returned.
*
****************************************************************************/
int libelf_registry_foreach(mod_callback_t callback, FAR void *arg)
{
FAR struct module_s *modp;
int ret = OK;
libelf_registry_lock();
for (modp = g_mod_registry; modp != NULL; modp = modp->flink)
{
ret = callback(modp, arg);
if (ret != 0)
{
break;
}
}
libelf_registry_unlock();
return ret;
}