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/*
 * jit-cpp-mangle.c - Perform C++ name mangling.
 *
 * Copyright (C) 2004  Southern Storm Software, Pty Ltd.
 *
 * This file is part of the libjit library.
 *
 * The libjit library is free software: you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation, either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * The libjit library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with the libjit library.  If not, see
 * <http://www.gnu.org/licenses/>.
 */

#include <jit/jit-dynamic.h>
#include <jit/jit.h>
#include <config.h>
#include <stdio.h>

/*@

@cindex Name mangling

Sometimes you want to retrieve a C++ method from a dynamic library
using @code{jit_dynlib_get_symbol}.  Unfortunately, C++ name mangling
rules differ from one system to another, making this process very
error-prone.

The functions that follow try to help.  They aren't necessarily fool-proof,
but they should work in the most common cases.  The only alternative is
to wrap your C++ library with C functions, so that the names are predictable.

The basic idea is that you supply a description of the C++ method that
you wish to access, and these functions return a number of candidate forms
that you can try with @code{jit_dynlib_get_symbol}.  If one form fails,
you move on and try the next form, until either symbol lookup succeeds
or until all forms have been exhausted.

@noindent
The following code demonstrates how to resolve a global function:

@example
jit_dynlib_handle_t handle;
jit_type_t signature;
int form = 0;
void *address = 0;
char *mangled;

while((mangled = jit_mangle_global_function
             ("foo", signature, form)) != 0)
@{
    address = jit_dynlib_get_symbol(handle, mangled);
    if(address != 0)
    @{
        break;
    @}
    jit_free(mangled);
    ++form;
@}

if(address)
@{
    printf("%s = 0x%lx\n", mangled, (long)address);
@}
else
@{
    printf("could not resolve foo\n");
@}
@end example

This mechanism typically cannot be used to obtain the entry points for
@code{inline} methods.  You will need to make other arrangements to
simulate the behaviour of inline methods, or recompile your dynamic C++
library in a mode that explicitly exports inlines.

C++ method names are very picky about types.  On 32-bit systems,
@code{int} and @code{long} are the same size, but they are mangled
to different characters.  To ensure that the correct function is
picked, you should use @code{jit_type_sys_int}, @code{jit_type_sys_long}, etc
instead of the platform independent types.  If you do use a platform
independent type like @code{jit_type_int}, this library will try to
guess which system type you mean, but the guess will most likely be wrong.

@*/

/*