/*
 * Each dll should include this file.
 *
 * ----------------------------------------------------------------
 *
 * @begin[license]
 * Copyright (C) 2005 Mojave Group, Caltech
 *
 * This 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,
 * version 2.1 of the License.
 * 
 * This 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 this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 * 
 * Additional permission is given to link this library with the
 * OpenSSL project's "OpenSSL" library, and with the OCaml runtime,
 * and you may distribute the linked executables.  See the file
 * LICENSE.libmojave for more details.
 *
 * Author: Jason Hickey
 * @email{jyh@cs.caltech.edu}
 * @end[license]
 */
#ifndef _LM_DLL_HOOKS_H
#define _LM_DLL_HOOKS_H

#include "lm_dll.h"

/************************************************************************
 * Initialization code.
 */
static DllHooks *dll_hooks;
static value dll_callback_handler;

#undef alloc
#undef alloc_tuple
#undef alloc_custom
#undef copy_string
#undef copy_string_array
#undef copy_int32
#undef copy_double
#undef named_value
#undef callback
#undef callback2
#undef callback_exn
#undef callback2_exn
#undef register_global_root

#define alloc(n, t)                     (dll_hooks->alloc_hook(n, t))
#define alloc_tuple(n)                  (dll_hooks->alloc_tuple_hook(n))
#define alloc_custom(ops, size, i, j)   (dll_hooks->alloc_custom_hook(ops, size, i, j))
#define copy_string(s)                  (dll_hooks->copy_string_hook(s))
#define copy_string_array(s)            (dll_hooks->copy_string_array_hook(s))
#define copy_int32(i)                   (dll_hooks->copy_int32_hook(i))
#define copy_double(x)                  (dll_hooks->copy_double_hook(x))
#define named_value(name)               (dll_hooks->named_value_hook(name))
#define callback(f, arg1)               (dll_hooks->callback1_hook(f, arg1))
#define callback2(f, arg1, arg2)        (dll_hooks->callback2_hook(f, arg1, arg2))
#define callback_exn(f, arg1)           (dll_hooks->callback1_exn_hook(f, arg1))
#define callback2_exn(f, arg1, arg2)    (dll_hooks->callback2_exn_hook(f, arg1, arg2))
#define register_global_root(v)         (dll_hooks->register_global_root_hook(v))
#define caml_modify(vp, v)              (dll_hooks->modify(vp, v))

/*
 * Strings have special marshalers.
 */
static value dll_unmarshal_string(const char *s)
{
    value v;

    if(s)
        v = copy_string(s);
    else
        v = 0;
    return v;
}

static char *dll_marshal_string(value v)
{
    char *s;

    if(v)
        s = String_val(v);
    else
        s = 0;
    return s;
}

/************************************************************************
 * Pointers are custom blocks.
 */
typedef struct _dll_pointer {
    void *p;
} DllPointer;

static DllPointer dll_null_pointer;

#define DllPointer_val(v)         ((DllPointer *) Data_custom_val(v))
#define DllPointer_pointer_val(v) (DllPointer_val(v)->p)

static int dll_pointer_compare(value v1, value v2)
{
    void *p1 = DllPointer_pointer_val(v1);
    void *p2 = DllPointer_pointer_val(v2);
    int i;

    if(p1 < p2)
        i = -1;
    else if(p1 > p2)
        i = 1;
    else
        i = 0;
    return i;
}

static long dll_pointer_hash(value v)
{
    CAMLparam1(v);
    void *p = DllPointer_pointer_val(v);
    CAMLreturn((long) p);
}

static void dll_pointer_serialize(value v, unsigned long *wsize_32, unsigned long *wsize_64)
{
    *wsize_32 = 4;
    *wsize_64 = 8;
}

static unsigned long dll_pointer_deserialize(void *dst)
{
    *(DllPointer *)dst = dll_null_pointer;
    return sizeof(DllPointer);
}

static struct custom_operations dll_pointer_ops = {
    "dll_pointer",
    custom_finalize_default,
    dll_pointer_compare,
    dll_pointer_hash,
    dll_pointer_serialize,
    dll_pointer_deserialize
};

static inline value dll_unmarshal_pointer(void *p)
{
    value v = alloc_custom(&dll_pointer_ops, sizeof(DllPointer), 0, 1);
    DllPointer_pointer_val(v) = p;
    return v;
}

static inline void *dll_marshal_pointer(value v)
{
    return DllPointer_pointer_val(v);
}

#endif /* _LM_DLL_HOOKS_H */