loader.h

/*
 * Copyright (C) 2015, 2016 Igalia S.L.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "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 COPYRIGHT
 * HOLDER OR CONTRIBUTORS 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.
 */

#if !defined(__WPE_H_INSIDE__) && !defined(WPE_COMPILATION)
#error "Only <wpe/wpe.h> can be included directly."
#endif

#ifndef wpe_loader_h
#define wpe_loader_h

/**
 * SECTION:loader
 * @short_description: Loader and Initialization
 * @title: Loader
 */

#if defined(WPE_COMPILATION)
#include <wpe/export.h>
#endif

#include <stdbool.h>

#ifdef __cplusplus
extern "C" {
#endif

/**
 * wpe_loader_interface:
 * @load_object: Callback invoked by `libwpe` to instantiate objects.
 *
 * An implementation of a WPE backend *must* define a `_wpe_loader_interface`
 * symbol of this type.
 */
struct wpe_loader_interface {
    void* (*load_object)(const char*);

    /*< private >*/
    void (*_wpe_reserved0)(void);
    void (*_wpe_reserved1)(void);
    void (*_wpe_reserved2)(void);
    void (*_wpe_reserved3)(void);
};

/**
 * wpe_loader_init:
 * @impl_library_name: (transfer none): Name of the shared library object
 *     to load as WPE backend implementation.
 *
 * Initializes the `libwpe` object loader. If the @impl_library_name is a
 * full path it will be used as-is, while a relative path will cause the
 * backend implementation library to be searched for in a fixed location.
 *
 * The backends location is determined at build time, and typically will
 * be `<prefix>/lib/wpe-<apiversion>`, where `<prefix>` is the installation
 * prefix and `<apiversion>` is the libwpe API version being used. See the
 * [backend implementation
 * documentation](backend-implementing.md#Installation) for more.
 *
 * Returns: Whether initialization succeeded.
 */
WPE_EXPORT
bool
wpe_loader_init(const char* impl_library_name);

/**
 * wpe_loader_get_loaded_implementation_library_name:
 *
 * Obtain the name of the shared library object loaded as WPE backend
 * implementation. Note that in general this will return the actual location
 * of the backend being used, which may not be the same value passed to
 * wpe_loader_init().
 *
 * Returns: (transfer none): Path of the shared library object for the
 *     backend implementation.
 */
WPE_EXPORT
const char*
wpe_loader_get_loaded_implementation_library_name(void);

#ifdef __cplusplus
}
#endif

#endif /* wpe_loader_h */