mirror of
https://github.com/apache/nuttx.git
synced 2025-05-08 22:32:04 +08:00
52482219c8
Renaming "modlib" to "libelf" is more in line with the implementation content, which makes it easier for individual developers to understand the capabilities of this module. CONFIG_LIBC_MODLIB -> CONFIG_LIBC_ELF Signed-off-by: chao an <anchao.archer@bytedance.com>
117 lines
3.9 KiB
C
117 lines
3.9 KiB
C
/****************************************************************************
|
|
* libs/libc/elf/elf_getsymbol.c
|
|
*
|
|
* 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 <assert.h>
|
|
#include <debug.h>
|
|
#include <errno.h>
|
|
|
|
#include <nuttx/lib/elf.h>
|
|
#include <nuttx/symtab.h>
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: libelf_getsymbol
|
|
*
|
|
* Description:
|
|
* libelf_getsymbol() returns the address of a symbol defined within the
|
|
* object that was previously made accessible through a libelf_getsymbol()
|
|
* call. handle is the value returned from a call to libelf_insert() (and
|
|
* which has not since been released via a call to libelf_remove()),
|
|
* name is the symbol's name as a character string.
|
|
*
|
|
* The returned symbol address will remain valid until libelf_remove() is
|
|
* called.
|
|
*
|
|
* Input Parameters:
|
|
* handle - The opaque, non-NULL value returned by a previous successful
|
|
* call to libelf_insert().
|
|
* name - A pointer to the symbol name string.
|
|
*
|
|
* Returned Value:
|
|
* The address associated with the symbol is returned on success.
|
|
* If handle does not refer to a valid module opened by libelf_insert(),
|
|
* or if the named libelf_symbol cannot be found within any of the objects
|
|
* associated with handle, libelf_getsymbol() will return NULL and the
|
|
* errno variable will be set appropriately.
|
|
*
|
|
* NOTE: This means that the address zero can never be a valid return
|
|
* value.
|
|
*
|
|
****************************************************************************/
|
|
|
|
FAR const void *libelf_getsymbol(FAR void *handle, FAR const char *name)
|
|
{
|
|
FAR struct module_s *modp = handle;
|
|
FAR const struct symtab_s *symbol;
|
|
int err;
|
|
int ret;
|
|
|
|
/* Verify that the module is in the registry */
|
|
|
|
libelf_registry_lock();
|
|
ret = libelf_registry_verify(modp);
|
|
if (ret < 0)
|
|
{
|
|
berr("ERROR: Failed to verify module: %d\n", ret);
|
|
err = -ret;
|
|
goto errout_with_lock;
|
|
}
|
|
|
|
/* Does the module have a symbol table? */
|
|
|
|
if (modp->modinfo.exports == NULL || modp->modinfo.nexports == 0)
|
|
{
|
|
berr("ERROR: Module has no symbol table\n");
|
|
err = ENOENT;
|
|
goto errout_with_lock;
|
|
}
|
|
|
|
/* Search the symbol table for the matching symbol */
|
|
|
|
symbol = symtab_findbyname(modp->modinfo.exports, name,
|
|
modp->modinfo.nexports);
|
|
|
|
libelf_registry_unlock();
|
|
if (symbol == NULL)
|
|
{
|
|
berr("ERROR: Failed to find symbol in symbol \"%s\" in table\n", name);
|
|
set_errno(ENOENT);
|
|
return NULL;
|
|
}
|
|
|
|
/* Return the address within the module associated with the symbol */
|
|
|
|
DEBUGASSERT(symbol->sym_value != NULL);
|
|
return symbol->sym_value;
|
|
|
|
errout_with_lock:
|
|
libelf_registry_unlock();
|
|
set_errno(err);
|
|
return NULL;
|
|
}
|