taisei/src/vfs/private.h
2024-05-17 14:11:48 +02:00

135 lines
5.3 KiB
C

/*
* This software is licensed under the terms of the MIT License.
* See COPYING for further information.
* ---
* Copyright (c) 2011-2024, Lukas Weber <laochailan@web.de>.
* Copyright (c) 2012-2024, Andrei Alexeyev <akari@taisei-project.org>.
*/
#pragma once
#include "taisei.h"
/*
* This file should not be included by code outside of the vfs/ directory
*/
#include "public.h" // IWYU pragma: export
#include "pathutil.h" // IWYU pragma: export
#include "error.h" // IWYU pragma: export
#include "util.h"
typedef struct VFSNode VFSNode;
typedef struct VFSNodeFuncs VFSNodeFuncs;
typedef void (*VFSShutdownHandler)(void *arg);
struct VFSNodeFuncs {
char* (*repr)(VFSNode *node) attr_nonnull(1);
void (*free)(VFSNode *node) attr_nonnull(1);
VFSInfo (*query)(VFSNode *node) attr_nonnull(1);
char* (*syspath)(VFSNode *node) attr_nonnull(1);
bool (*mount)(VFSNode *mountroot, const char *subname, VFSNode *mountee) attr_nonnull(1, 3);
bool (*unmount)(VFSNode *mountroot, const char *subname) attr_nonnull(1);
VFSNode* (*locate)(VFSNode *dirnode, const char* path) attr_nonnull(1, 2);
const char* (*iter)(VFSNode *dirnode, void **opaque) attr_nonnull(1);
void (*iter_stop)(VFSNode *dirnode, void **opaque) attr_nonnull(1);
bool (*mkdir)(VFSNode *parent, const char *subdir) attr_nonnull(1);
SDL_RWops* (*open)(VFSNode *filenode, VFSOpenMode mode) attr_nonnull(1);
};
struct VFSNode {
char as_generic[0];
const VFSNodeFuncs *funcs;
SDL_atomic_t refcount;
};
#define VFS_NODE_TYPE_FUNCS_NAME(_typename) _vfs_funcs_##_typename
#define VFS_NODE_TYPE(_typename, ...) \
typedef struct _typename { \
VFSNode as_generic; \
struct __VA_ARGS__; \
} _typename; \
extern const VFSNodeFuncs VFS_NODE_TYPE_FUNCS_NAME(_typename)
#define VFS_NODE_FUNCS(_typename, ...) \
const VFSNodeFuncs VFS_NODE_TYPE_FUNCS_NAME(_typename) = __VA_ARGS__
#define IS_OF_VFS_NODE_BASE_TYPE(_node) \
__builtin_types_compatible_p(VFSNode, typeof(*(_node)))
#define IS_OF_VFS_NODE_DERIVED_TYPE(_node) \
(__builtin_types_compatible_p(VFSNode, typeof((_node)->as_generic)) \
&& offsetof(typeof(*(_node)), as_generic) == 0)
#define IS_OF_VFS_NODE_TYPE(_node) \
IS_OF_VFS_NODE_BASE_TYPE(_node) || IS_OF_VFS_NODE_DERIVED_TYPE(_node)
#define VFS_NODE_ASSERT_VALID(_node) \
static_assert(IS_OF_VFS_NODE_TYPE(_node), "Expected a VFSNode or derived type")
#define VFS_NODE_AS_BASE(_node) ({ \
VFS_NODE_ASSERT_VALID(_node); \
__builtin_choose_expr(IS_OF_VFS_NODE_BASE_TYPE(_node), (_node), &(_node)->as_generic); \
})
#define VFS_NODE_TRY_CAST(_typename, _node) ({ \
VFSNode *_base_node = _node; \
static_assert(IS_OF_VFS_NODE_DERIVED_TYPE( (&(_typename){}) ), \
"Typename must be of a VFSNode-derived type"); \
_typename* _n = UNION_CAST(VFSNode*, _typename*, NOT_NULL(_base_node)); \
LIKELY(_n->as_generic.funcs == &VFS_NODE_TYPE_FUNCS_NAME(_typename))? _n : NULL; \
})
#define VFS_NODE_CAST(_typename, _node) \
NOT_NULL(VFS_NODE_TRY_CAST(_typename, _node))
#define VFS_ALLOC(_typename, ...) ({ \
auto _node = ALLOC(_typename, ##__VA_ARGS__); \
static_assert(IS_OF_VFS_NODE_DERIVED_TYPE(_node), \
"Typename must be of a VFSNode-derived type"); \
_node->as_generic.funcs = &VFS_NODE_TYPE_FUNCS_NAME(_typename); \
vfs_incref(_node); \
_node; \
})
extern VFSNode *vfs_root;
void vfs_incref(VFSNode *node) attr_nonnull(1);
bool vfs_decref(VFSNode *node);
bool vfs_mount(VFSNode *root, const char *mountpoint, VFSNode *subtree) attr_nonnull(1, 3) attr_nodiscard;
bool vfs_mount_or_decref(VFSNode *root, const char *mountpoint, VFSNode *subtree) attr_nonnull(1, 3) attr_nodiscard;
VFSNode *vfs_locate(VFSNode *root, const char *path) attr_nonnull(1, 2) attr_nodiscard;
// Light wrappers around the virtual functions, safe to call even on nodes that
// don't implement the corresponding method. "free" is not included, there should
// be no reason to call it. It wouldn't do what you'd expect anyway; use vfs_decref.
char *vfs_node_repr(VFSNode *node, bool try_syspath) attr_returns_allocated attr_nonnull(1);
VFSInfo vfs_node_query(VFSNode *node) attr_nonnull(1) attr_nodiscard attr_nonnull(1);
char *vfs_node_syspath(VFSNode *node) attr_nonnull(1) attr_returns_max_aligned attr_nodiscard attr_nonnull(1);
bool vfs_node_mount(VFSNode *mountroot, const char *subname, VFSNode *mountee) attr_nonnull(1, 3);
bool vfs_node_unmount(VFSNode *mountroot, const char *subname) attr_nonnull(1);
VFSNode *vfs_node_locate(VFSNode *root, const char *path) attr_nonnull(1, 2) attr_nodiscard;
const char *vfs_node_iter(VFSNode *node, void **opaque) attr_nonnull(1);
void vfs_node_iter_stop(VFSNode *node, void **opaque) attr_nonnull(1);
bool vfs_node_mkdir(VFSNode *parent, const char *subdir) attr_nonnull(1);
SDL_RWops *vfs_node_open(VFSNode *filenode, VFSOpenMode mode) attr_nonnull(1) attr_nodiscard;
// NOTE: convenience wrappers added on demand
#define vfs_incref(node) \
vfs_incref(VFS_NODE_AS_BASE(node))
#define vfs_decref(node) \
vfs_decref(VFS_NODE_AS_BASE(node))
#define vfs_locate(root, path) \
vfs_locate(VFS_NODE_AS_BASE(root), path)
#define vfs_node_repr(node, try_syspath) \
vfs_node_repr(VFS_NODE_AS_BASE(node), try_syspath)
void vfs_hook_on_shutdown(VFSShutdownHandler, void *arg);
void vfs_print_tree_recurse(SDL_RWops *dest, VFSNode *root, char *prefix, const char *name) attr_nonnull(1, 2, 3, 4);