pkgconf/libpkgconf/cache.c

168 lines
4.4 KiB
C

/*
* cache.c
* package object cache
*
* Copyright (c) 2013 pkgconf authors (see AUTHORS).
*
* 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 'as is' and without any warranty, express or
* implied. In no event shall the authors be liable for any damages arising
* from the use of this software.
*/
#include <libpkgconf/stdinc.h>
#include <libpkgconf/libpkgconf.h>
/*
* !doc
*
* libpkgconf `cache` module
* =========================
*
* The libpkgconf `cache` module manages a package/module object cache, allowing it to
* avoid loading duplicate copies of a package/module.
*
* A cache is tied to a specific pkgconf client object, so package objects should not
* be shared across threads.
*/
/*
* !doc
*
* .. c:function:: pkgconf_pkg_t *pkgconf_cache_lookup(const pkgconf_client_t *client, const char *id)
*
* Looks up a package in the cache given an `id` atom,
* such as ``gtk+-3.0`` and returns the already loaded version
* if present.
*
* :param pkgconf_client_t* client: The client object to access.
* :param char* id: The package atom to look up in the client object's cache.
* :return: A package object if present, else ``NULL``.
* :rtype: pkgconf_pkg_t *
*/
pkgconf_pkg_t *
pkgconf_cache_lookup(pkgconf_client_t *client, const char *id)
{
pkgconf_node_t *node;
PKGCONF_FOREACH_LIST_ENTRY(client->pkg_cache.head, node)
{
pkgconf_pkg_t *pkg = node->data;
if (!strcmp(pkg->id, id))
{
PKGCONF_TRACE(client, "found: %s @%p", id, pkg);
return pkgconf_pkg_ref(client, pkg);
}
}
PKGCONF_TRACE(client, "miss: %s", id);
return NULL;
}
/*
* !doc
*
* .. c:function:: void pkgconf_cache_add(pkgconf_client_t *client, pkgconf_pkg_t *pkg)
*
* Adds an entry for the package to the package cache.
* The cache entry must be removed if the package is freed.
*
* :param pkgconf_client_t* client: The client object to modify.
* :param pkgconf_pkg_t* pkg: The package object to add to the client object's cache.
* :return: nothing
*/
void
pkgconf_cache_add(pkgconf_client_t *client, pkgconf_pkg_t *pkg)
{
if (pkg == NULL)
return;
pkgconf_pkg_ref(client, pkg);
pkgconf_node_insert(&pkg->cache_iter, pkg, &client->pkg_cache);
PKGCONF_TRACE(client, "added @%p to cache", pkg);
/* mark package as cached */
pkg->flags |= PKGCONF_PKG_PROPF_CACHED;
}
/*
* !doc
*
* .. c:function:: void pkgconf_cache_remove(pkgconf_client_t *client, pkgconf_pkg_t *pkg)
*
* Deletes a package from the client object's package cache.
*
* :param pkgconf_client_t* client: The client object to modify.
* :param pkgconf_pkg_t* pkg: The package object to remove from the client object's cache.
* :return: nothing
*/
void
pkgconf_cache_remove(pkgconf_client_t *client, pkgconf_pkg_t *pkg)
{
if (pkg == NULL)
return;
if (!(pkg->flags & PKGCONF_PKG_PROPF_CACHED))
return;
PKGCONF_TRACE(client, "removed @%p from cache", pkg);
pkgconf_node_delete(&pkg->cache_iter, &client->pkg_cache);
}
static inline void
clear_dependency_matches(pkgconf_list_t *list)
{
pkgconf_node_t *iter;
PKGCONF_FOREACH_LIST_ENTRY(list->head, iter)
{
pkgconf_dependency_t *dep = iter->data;
dep->match = NULL;
}
}
/*
* !doc
*
* .. c:function:: void pkgconf_cache_free(pkgconf_client_t *client)
*
* Releases all resources related to a client object's package cache.
* This function should only be called to clear a client object's package cache,
* as it may release any package in the cache.
*
* :param pkgconf_client_t* client: The client object to modify.
*/
void
pkgconf_cache_free(pkgconf_client_t *client)
{
pkgconf_node_t *iter, *iter2;
/* first we clear cached match pointers */
PKGCONF_FOREACH_LIST_ENTRY(client->pkg_cache.head, iter)
{
pkgconf_pkg_t *pkg = iter->data;
clear_dependency_matches(&pkg->required);
clear_dependency_matches(&pkg->requires_private);
clear_dependency_matches(&pkg->provides);
clear_dependency_matches(&pkg->conflicts);
}
/* now forcibly free everything */
PKGCONF_FOREACH_LIST_ENTRY_SAFE(client->pkg_cache.head, iter2, iter)
{
pkgconf_pkg_t *pkg = iter->data;
pkgconf_pkg_free(client, pkg);
}
memset(&client->pkg_cache, 0, sizeof client->pkg_cache);
PKGCONF_TRACE(client, "cleared package cache");
}