mirror of
https://github.com/RT-Thread/rt-thread.git
synced 2025-01-21 12:03:31 +08:00
78 lines
2.2 KiB
C
78 lines
2.2 KiB
C
/*
|
|
* Copyright (c) 2006-2024 RT-Thread Development Team
|
|
*
|
|
* SPDX-License-Identifier: Apache-2.0
|
|
*
|
|
* Change Logs:
|
|
* Date Author Notes
|
|
* 2010-11-17 yi.qiu first version
|
|
*/
|
|
|
|
#include <rtthread.h>
|
|
#include <rtm.h>
|
|
#include <string.h>
|
|
|
|
#include "dlmodule.h"
|
|
|
|
#define MODULE_ROOT_DIR "/modules"
|
|
|
|
/**
|
|
* @brief dynamically load a shared library at runtime.
|
|
*
|
|
* @param filename the path to the shared library to load, which shouldn't be set to NULL.
|
|
* @param flags options for loading the shared library.
|
|
* @return void* on success, it returns a handle (a pointer) to the opened shared library, otherwise it returns NULL.
|
|
*
|
|
* @note This function is an API of POSIX standard, which is used for dynamically loading shared libraries at runtime.
|
|
* the function first tries to check if the module is already loaded, by finding module in module list.
|
|
* If module is found in memory (RT_NULL check fails), the reference count (nref) is incremented.
|
|
* Otherwise, dlmodule_load() will be called to load the module into memory.
|
|
* A handle (a pointer to the module) is returned at last, which can be used with other functions like dlsym().
|
|
*/
|
|
void* dlopen(const char *filename, int flags)
|
|
{
|
|
struct rt_dlmodule *module;
|
|
char *fullpath;
|
|
const char*def_path = MODULE_ROOT_DIR;
|
|
|
|
/* check parameters */
|
|
RT_ASSERT(filename != RT_NULL);
|
|
|
|
if (filename[0] != '/') /* it's a relative path, prefix with MODULE_ROOT_DIR */
|
|
{
|
|
fullpath = rt_malloc(strlen(def_path) + strlen(filename) + 2);
|
|
|
|
/* join path and file name */
|
|
rt_snprintf(fullpath, strlen(def_path) + strlen(filename) + 2,
|
|
"%s/%s", def_path, filename);
|
|
}
|
|
else
|
|
{
|
|
fullpath = (char*)filename; /* absolute path, use it directly */
|
|
}
|
|
|
|
rt_enter_critical();
|
|
|
|
/* find in module list */
|
|
module = dlmodule_find(fullpath);
|
|
|
|
if(module != RT_NULL)
|
|
{
|
|
rt_exit_critical();
|
|
module->nref++;
|
|
}
|
|
else
|
|
{
|
|
rt_exit_critical();
|
|
module = dlmodule_load(fullpath);
|
|
}
|
|
|
|
if(fullpath != filename)
|
|
{
|
|
rt_free(fullpath);
|
|
}
|
|
|
|
return (void*)module;
|
|
}
|
|
RTM_EXPORT(dlopen);
|