/*
 * atheme-services: A collection of minimalist IRC services   
 * linker.c: Abstraction of the dynamic linking system.
 *
 * Copyright (c) 2005-2007 Atheme Project (http://www.atheme.org)           
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "atheme.h"
#include "linker.h"

#include <dlfcn.h>

#ifdef __OpenBSD__
# define RTLD_NOW RTLD_LAZY
#endif

#ifndef RTLD_LOCAL
#define RTLD_LOCAL 0
#endif

#ifndef __HPUX__
# define PLATFORM_SUFFIX ".so"
#else
# define PLATFORM_SUFFIX ".sl"
#endif

/*
 * linker_open()
 *
 * Inputs:
 *       path to file to open
 *
 * Outputs:
 *       linker handle.
 *
 * Side Effects:
 *       a shared module is loaded into the application's memory space
 */
void *linker_open(const char *path)
{
	return dlopen(path, RTLD_NOW | RTLD_LOCAL);
}

/*
 * linker_open_ext()
 *
 * Inputs:
 *       path to file to open
 *
 * Outputs:
 *       linker handle
 *
 * Side Effects:
 *       the extension is appended if it's not already there.
 *       a shared module is loaded into the application's memory space
 */
void *linker_open_ext(const char *path)
{
	char *buf = smalloc(strlen(path) + 20);
	void *ret;
	
	strlcpy(buf, path, strlen(path) + 20);

	if (!strstr(buf, PLATFORM_SUFFIX))
		strlcat(buf, PLATFORM_SUFFIX, strlen(path) + 20);

	ret = linker_open(buf);
	free(buf);
	return ret;
}

/*
 * linker_getsym()
 *
 * Inputs:
 *       linker handle, symbol to retrieve
 *
 * Outputs:
 *       pointer to symbol, or NULL if no symbol.
 *
 * Side Effects:
 *       none
 */
void *linker_getsym(void *vptr, const char *sym)
{
	return dlsym(vptr, sym);
}

/*
 * linker_close()
 *
 * Inputs:
 *       linker handle
 *
 * Outputs:
 *       none
 *
 * Side Effects:
 *       the module is unloaded from the linker
 */
void linker_close(void *vptr)
{
	dlclose(vptr);
}

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 */