/*
* Copyright 2010 University of Helsinki.
*
* This file is part of libgu.
*
* Libgu 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 3 of the License, or (at your
* option) any later version.
*
* Libgu 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 libgu. If not, see .
*/
/** @file
*
* Lightweight tagged data.
*/
#ifndef GU_VARIANT_H_
#define GU_VARIANT_H_
#include
#include
#include
/** @name Variants
* @{
*/
typedef struct GuVariant GuVariant;
void* gu_alloc_variant(uint8_t tag,
size_t size, size_t align,
GuVariant* variant_out, GuPool* pool);
GuVariant gu_make_variant(uint8_t tag,
size_t size, size_t align,
const void* init, GuPool* pool);
#define gu_new_variant(tag, type, variant_out, pool) \
((type*)gu_alloc_variant(tag, sizeof(type), \
gu_alignof(type), variant_out, pool))
/**<
* @hideinitializer */
#define gu_new_variant_i(POOL, TAG, T, ...) \
gu_make_variant(TAG, sizeof(T), gu_alignof(T), \
&(T){ __VA_ARGS__ }, POOL)
#define gu_new_flex_variant(tag, type, flex_mem, n_elems, variant_out, pool) \
((type*)gu_alloc_variant(tag, \
GU_FLEX_SIZE(type, flex_mem, n_elems), \
gu_flex_alignof(type), \
variant_out, pool))
/**<
* @hideinitializer */
enum {
GU_VARIANT_NULL = -1
};
int gu_variant_tag(GuVariant variant);
void* gu_variant_data(GuVariant variant);
typedef struct GuVariantInfo GuVariantInfo;
struct GuVariantInfo {
int tag;
void* data;
};
GuVariantInfo gu_variant_open(GuVariant variant);
/** @privatesection */
struct GuVariant {
uintptr_t p;
/**< @private */
};
/** @} */
static inline void*
gu_variant_to_ptr(GuVariant variant)
{
return (void*)variant.p;
}
static inline GuVariant
gu_variant_from_ptr(const void* p)
{
GuVariant v = { (uintptr_t)p };
return v;
}
extern const GuVariant gu_null_variant;
static inline bool
gu_variant_is_null(GuVariant v) {
return ((void*)v.p == NULL);
}
// variant
typedef const struct GuConstructor GuConstructor;
struct GuConstructor {
int c_tag;
const char* c_name;
const GuType* type;
};
#define GU_CONSTRUCTOR_V(ctag, c_type) { \
.c_tag = ctag, \
.c_name = #ctag, \
.type = c_type \
}
#define GU_CONSTRUCTOR(ctag, t_) \
GU_CONSTRUCTOR_V(ctag, gu_type(t_))
#define GU_CONSTRUCTOR_P(ctag, t_) \
GU_CONSTRUCTOR_V(ctag, gu_ptr_type(t_))
#define GU_CONSTRUCTOR_S(ctag, t_, ...) \
GU_CONSTRUCTOR_V(ctag, GU_TYPE_LIT(struct, t_, __VA_ARGS__))
#define GU_CONSTRUCTOR_S1(ctag, t_, mem1_, type1_) \
GU_CONSTRUCTOR_S(ctag, t_, \
GU_MEMBER(t_, mem1_, type1_))
#define GU_CONSTRUCTOR_S2(ctag, t_, mem1_, type1_, mem2_, type2_) \
GU_CONSTRUCTOR_S(ctag, t_, \
GU_MEMBER(t_, mem1_, type1_), \
GU_MEMBER(t_, mem2_, type2_))
typedef GuSList(GuConstructor) GuConstructors;
typedef const struct GuVariantType GuVariantType, GuType_GuVariant;
struct GuVariantType {
GuType_repr repr_base;
GuConstructors ctors;
};
#define GU_TYPE_INIT_GuVariant(k_, t_, ...) { \
.repr_base = GU_TYPE_INIT_repr(k_, GuVariant, _), \
.ctors = GU_SLIST(GuConstructor, __VA_ARGS__) \
}
extern GU_DECLARE_KIND(GuVariant);
#endif // GU_VARIANT_H_