WIP: Visitor pattern implementation for serialization

distr/flecs.h

@@ -189,6 +189,7 @@
 // #define FLECS_C          /**< C API convenience macros, always enabled */
 #define FLECS_CPP           /**< C++ API */
 #define FLECS_MODULE        /**< Module support */
+#define FLECS_SERIALIZE     /**< API for serializing/visiting entity-component graph */
 #define FLECS_SCRIPT        /**< ECS data definition format */
 #define FLECS_STATS         /**< Track runtime statistics */
 #define FLECS_METRICS       /**< Expose component data as statistics */
@@ -13350,6 +13351,10 @@ void FlecsAlertsImport(
 #define FLECS_SCRIPT
 #endif
 
+#ifndef FLECS_SERIALIZE
+#define FLECS_SERIALIZE
+#endif
+
 #ifndef FLECS_JSON_H
 #define FLECS_JSON_H
 
@@ -13763,6 +13768,142 @@ int ecs_world_to_json_buf(
 
 #endif
 
+#ifdef FLECS_SERIALIZE
+#ifdef FLECS_NO_SERIALIZE
+#error "FLECS_NO_SERIALIZE failed: SERIALIZE is required by other addons"
+#endif
+
+/**
+ * @file addons/serialize.h
+ * @brief Visitor-api addon.
+ *
+ * Implements visitor pattern to allow parsing of flecs entity-component
+ * graphs.
+ *
+ * Used by the json parser addon to serialize to json.
+ */
+
+#ifdef FLECS_SERIALIZE
+
+#ifndef FLECS_META
+#define FLECS_META
+#endif
+
+#ifndef FLECS_SCRIPT
+#define FLECS_SCRIPT
+#endif
+
+#ifndef FLECS_SERIALIZE_H
+#define FLECS_SERIALIZE_H
+
+/**
+ * @defgroup c_addons_serialize Serialize
+ * @ingroup c_addons
+ * Functions for user-defined serialization.
+ *
+ * @{
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** Visitor Seriailzation API
+ */
+typedef struct ecs_visitor_desc_t {
+    /** Here Be Visitor Functions
+     * If the visit has a return, it has some form of flow control.
+     */
+
+    /** visit primitives */
+    void (*visit_char)(const char value, void* user_data);
+    void (*visit_u8)(const uint8_t value, void* user_data);
+    void (*visit_u16)(const uint16_t value, void* user_data);
+    void (*visit_u32)(const uint32_t value, void* user_data);
+    void (*visit_u64)(const uint64_t value, void* user_data);
+    void (*visit_i8)(const int8_t value, void* user_data);
+    void (*visit_i16)(const int16_t value, void* user_data);
+    void (*visit_i32)(const int32_t value, void* user_data);
+    void (*visit_i64)(const int64_t value, void* user_data);
+    void (*visit_f32)(const float value, void* user_data);
+    void (*visit_f64)(const double value, void* user_data);
+    void (*visit_bool)(const bool value, void* user_data);
+    void (*visit_byte)(const unsigned char value, void* user_data);
+    void (*visit_uptr)(const uintptr_t value, void* user_data);
+    void (*visit_iptr)(const intptr_t value, void* user_data);
+    void (*visit_string)(const char* value, void* user_data);
+    void (*visit_entity)(const ecs_world_t*, const ecs_entity_t value, void* user_data);
+    void (*visit_id)(const ecs_world_t*, const ecs_id_t value, void* user_data);
+
+    void (*visit_member)(const char* member_name, void* user_data);
+
+    void (*visit_enum)(int32_t value, const char* constant_name, void* user_data);
+    struct {
+        int (*enter)(uint32_t initial_value, void* user_data);
+        void (*value)(uint32_t value, const char* constant_name, void* user_data);
+        void (*exit)(uint32_t values_visited, void* user_data);
+    } visit_bitmask;
+    struct {
+        void (*enter)(size_t size, void* user_data);
+        void (*next_value)(size_t index, void* user_data);
+        void (*exit)(void* user_data);
+    } visit_array;
+    struct {
+        void (*enter)(void* user_data);
+        void (*next_value)(size_t index, void* user_data);
+        void (*exit)(void* user_data);
+    } visit_struct;
+
+    struct {
+      void (*enter)(void* user_data);
+      void (*exit)(void* user_data);
+    } visit_iter_result;
+
+    void* (*exit)(void* user_data);
+    void* (*error)(void* user_data);
+
+    /** User Data that is handed out to each visit.
+     * Ex: JSON serialization passes a string buffer
+     */
+    void* user_data;
+
+    /** Used to indicate an error has occurred while visiting
+     */
+    bool _error;
+} ecs_visitor_desc_t;
+
+
+int ecs_ser_ptr(
+    const ecs_world_t *world,
+    ecs_entity_t type,
+    const void *ptr,
+    ecs_visitor_desc_t *visitor_desc);
+
+int ecs_ser_array(
+    const ecs_world_t *world,
+    ecs_entity_t type,
+    const void *ptr,
+    int32_t count,
+    ecs_visitor_desc_t *visitor_desc);
+
+void* ecs_ser_entity(
+    const ecs_world_t *stage,
+    ecs_entity_t entity,
+    ecs_visitor_desc_t *visitor_desc,
+    const ecs_entity_to_json_desc_t *desc);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
+/** @} */
+
+#endif
+
+#endif
+
 #ifdef FLECS_UNITS
 #ifdef FLECS_NO_UNITS
 #error "FLECS_NO_UNITS failed: UNITS is required by other addons"
@@ -14155,6 +14296,9 @@ void FlecsUnitsImport(
 #define FLECS_DOC
 #endif
 
+#ifndef FLECS_SERIALIZE
+#define FLECS_SERIALIZE
+#endif
 
 #ifndef FLECS_SCRIPT_H
 #define FLECS_SCRIPT_H

include/flecs.h

@@ -187,6 +187,7 @@
 // #define FLECS_C          /**< C API convenience macros, always enabled */
 #define FLECS_CPP           /**< C++ API */
 #define FLECS_MODULE        /**< Module support */
+#define FLECS_SERIALIZE     /**< API for serializing/visiting entity-component graph */
 #define FLECS_SCRIPT        /**< ECS data definition format */
 #define FLECS_STATS         /**< Track runtime statistics */
 #define FLECS_METRICS       /**< Expose component data as statistics */

include/flecs/addons/json.h

@@ -18,6 +18,10 @@
 #define FLECS_SCRIPT
 #endif
 
+#ifndef FLECS_SERIALIZE
+#define FLECS_SERIALIZE
+#endif
+
 #ifndef FLECS_JSON_H
 #define FLECS_JSON_H
 

include/flecs/addons/script.h

@@ -23,6 +23,9 @@
 #define FLECS_DOC
 #endif
 
+#ifndef FLECS_SERIALIZE
+#define FLECS_SERIALIZE
+#endif
 
 #ifndef FLECS_SCRIPT_H
 #define FLECS_SCRIPT_H

include/flecs/addons/serialize.h

@@ -0,0 +1,129 @@
+
+/**
+ * @file addons/serialize.h
+ * @brief Visitor-api addon.
+ *
+ * Implements visitor pattern to allow parsing of flecs entity-component
+ * graphs.
+ *
+ * Used by the json parser addon to serialize to json.
+ */
+
+#ifdef FLECS_SERIALIZE
+
+#ifndef FLECS_META
+#define FLECS_META
+#endif
+
+#ifndef FLECS_SCRIPT
+#define FLECS_SCRIPT
+#endif
+
+#ifndef FLECS_SERIALIZE_H
+#define FLECS_SERIALIZE_H
+
+/**
+ * @defgroup c_addons_serialize Serialize
+ * @ingroup c_addons
+ * Functions for user-defined serialization.
+ *
+ * @{
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** Visitor Seriailzation API
+ */
+typedef struct ecs_visitor_desc_t {
+    /** Here Be Visitor Functions
+     * If the visit has a return, it has some form of flow control.
+     */
+
+    /** visit primitives */
+    void (*visit_char)(const char value, void* user_data);
+    void (*visit_u8)(const uint8_t value, void* user_data);
+    void (*visit_u16)(const uint16_t value, void* user_data);
+    void (*visit_u32)(const uint32_t value, void* user_data);
+    void (*visit_u64)(const uint64_t value, void* user_data);
+    void (*visit_i8)(const int8_t value, void* user_data);
+    void (*visit_i16)(const int16_t value, void* user_data);
+    void (*visit_i32)(const int32_t value, void* user_data);
+    void (*visit_i64)(const int64_t value, void* user_data);
+    void (*visit_f32)(const float value, void* user_data);
+    void (*visit_f64)(const double value, void* user_data);
+    void (*visit_bool)(const bool value, void* user_data);
+    void (*visit_byte)(const unsigned char value, void* user_data);
+    void (*visit_uptr)(const uintptr_t value, void* user_data);
+    void (*visit_iptr)(const intptr_t value, void* user_data);
+    void (*visit_string)(const char* value, void* user_data);
+    void (*visit_entity)(const ecs_world_t*, const ecs_entity_t value, void* user_data);
+    void (*visit_id)(const ecs_world_t*, const ecs_id_t value, void* user_data);
+
+    void (*visit_member)(const char* member_name, void* user_data);
+
+    void (*visit_enum)(int32_t value, const char* constant_name, void* user_data);
+    struct {
+        int (*enter)(uint32_t initial_value, void* user_data);
+        void (*value)(uint32_t value, const char* constant_name, void* user_data);
+        void (*exit)(uint32_t values_visited, void* user_data);
+    } visit_bitmask;
+    struct {
+        void (*enter)(size_t size, void* user_data);
+        void (*next_value)(size_t index, void* user_data);
+        void (*exit)(void* user_data);
+    } visit_array;
+    struct {
+        void (*enter)(void* user_data);
+        void (*next_value)(size_t index, void* user_data);
+        void (*exit)(void* user_data);
+    } visit_struct;
+
+    struct {
+      void (*enter)(void* user_data);
+      void (*exit)(void* user_data);
+    } visit_iter_result;
+
+    void* (*exit)(void* user_data);
+    void* (*error)(void* user_data);
+
+    /** User Data that is handed out to each visit.
+     * Ex: JSON serialization passes a string buffer
+     */
+    void* user_data;
+
+    /** Used to indicate an error has occurred while visiting
+     */
+    bool _error;
+} ecs_visitor_desc_t;
+
+
+int ecs_ser_ptr(
+    const ecs_world_t *world,
+    ecs_entity_t type,
+    const void *ptr,
+    ecs_visitor_desc_t *visitor_desc);
+
+int ecs_ser_array(
+    const ecs_world_t *world,
+    ecs_entity_t type,
+    const void *ptr,
+    int32_t count,
+    ecs_visitor_desc_t *visitor_desc);
+
+void* ecs_ser_entity(
+    const ecs_world_t *stage,
+    ecs_entity_t entity,
+    ecs_visitor_desc_t *visitor_desc,
+    const ecs_entity_to_json_desc_t *desc);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
+/** @} */
+
+#endif

include/flecs/private/addons.h

@@ -154,6 +154,13 @@
 #include "../addons/json.h"
 #endif
 
+#ifdef FLECS_SERIALIZE
+#ifdef FLECS_NO_SERIALIZE
+#error "FLECS_NO_SERIALIZE failed: SERIALIZE is required by other addons"
+#endif
+#include "../addons/serialize.h"
+#endif
+
 #ifdef FLECS_UNITS
 #ifdef FLECS_NO_UNITS
 #error "FLECS_NO_UNITS failed: UNITS is required by other addons"

meson.build

@@ -33,6 +33,7 @@ flecs_src = files(
     'src/addons/json/serialize_iter_result_table.c',
     'src/addons/json/serialize_iter_result.c',
     'src/addons/json/serialize_iter.c',
+    'src/addons/json/serialize_json.c',
     'src/addons/json/serialize_query_info.c',
     'src/addons/json/serialize_type_info.c',
     'src/addons/json/serialize_value.c',
@@ -65,12 +66,15 @@ flecs_src = files(
     'src/addons/script/query_parser.c',
     'src/addons/script/script.c',
     'src/addons/script/serialize.c',
+    'src/addons/script/serialize_expr.c',
+    'src/addons/script/serialize_value.c',
     'src/addons/script/tokenizer.c',
     'src/addons/script/vars.c',
     'src/addons/script/visit_eval.c',
     'src/addons/script/visit_free.c',
     'src/addons/script/visit_to_str.c',
     'src/addons/script/visit.c',
+    'src/addons/serialize/serialize.c',
     'src/addons/system/system.c',
     'src/addons/timer.c',
     'src/addons/units.c',

src/addons/json/json.c

@@ -694,10 +694,4 @@ void flecs_json_id_member(
     }
 }
 
-ecs_primitive_kind_t flecs_json_op_to_primitive_kind(
-    ecs_meta_type_op_kind_t kind) 
-{
-    return kind - EcsOpPrimitive;
-}
-
 #endif