nuttx/libs/libc/modlib/modlib_unload.c
Neale Ferguson 5d7f2fdf16 Fix loading of ET_DYN type of shared objects
* build-globals.sh
  - Only look in the nuttx for external symbols used when loading
    dynamic shared objects

* include/elf64.h
  - Correct the type of fields in the Elf64_Phdr structure

* libs/libc/dlfcn/lib_dlclose.c
  - Distinguish between ET_DYN and other objects as the former
    has both text and data in a single allocation to reserve
    GOT offsets

* libs/libc/dlfcn/lib_dlopen.c
  - Code formatting

* libs/libc/modlib/modlib_bind.c
  - Distinguish between relocation entry sizes by section type
  - Handle RELA style relocations

* libs/libc/modlib/modlib_globals.S
  - Formatting fixes
  - Symbols should not be weak - they exist or they don't

* include/nuttx/lib/modlib.h
  - Add an inidcator to module_s to distinguish between ET_DYN and other

* libs/libc/modlib/modlib_load.c
  - ET_DYN objects need to keep the relative displacement between the text
    and data sections due to GOT references from the former to the latter.
    This also implies that linking may require modification from the default
    for the shared objects being produced. For example, default alignment may
    mean nearly 64K of wasted space.

* libs/libc/modlib/modlib_unload.c
  sched/module/mod_rmmod.c
  - Distingusih between freeing of ET_DYN storage and other as the former
    is a single allocation.

* libs/libc/modlib/mod_insmod.c
  - Cater for ET_DYN objects having init and preinit sections
2023-09-20 09:35:28 -04:00

93 lines
2.8 KiB
C

/****************************************************************************
* libs/libc/modlib/modlib_unload.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 <stdlib.h>
#include <debug.h>
#include <nuttx/lib/modlib.h>
#include "libc.h"
#include "modlib/modlib.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: modlib_unload
*
* Description:
* This function unloads the object from memory. This essentially undoes
* the actions of modlib_load(). It is called only under certain error
* conditions after the module has been loaded but not yet started.
*
* Returned Value:
* 0 (OK) is returned on success and a negated errno is returned on
* failure.
*
****************************************************************************/
int modlib_unload(FAR struct mod_loadinfo_s *loadinfo)
{
/* Free all working buffers */
modlib_freebuffers(loadinfo);
/* Release memory holding the relocated ELF image */
/* ET_DYN has a single allocation so we only free textalloc */
if (loadinfo->ehdr.e_type != ET_DYN)
{
if (loadinfo->textalloc != 0)
{
#if defined(CONFIG_ARCH_USE_TEXT_HEAP)
up_textheap_free((FAR void *)loadinfo->textalloc);
#else
lib_free((FAR void *)loadinfo->textalloc);
#endif
}
if (loadinfo->datastart != 0)
{
lib_free((FAR void *)loadinfo->datastart);
}
}
else
{
lib_free((FAR void *)loadinfo->textalloc);
}
/* Clear out all indications of the allocated address environment */
loadinfo->textalloc = 0;
loadinfo->datastart = 0;
loadinfo->textsize = 0;
loadinfo->datasize = 0;
return OK;
}