js_modules.h

#pragma once
 
#include <stdint.h>
#include "js_thread_i.h"
#include <flipper_application/flipper_application.h>
#include <flipper_application/plugins/plugin_manager.h>
#include <flipper_application/plugins/composite_resolver.h>
 
#define PLUGIN_APP_ID      "js"
#define PLUGIN_API_VERSION 1
 
#define JS_SDK_VENDOR "flipperdevices"
#define JS_SDK_MAJOR  0
#define JS_SDK_MINOR  3
 
#define JS_GET_INST(mjs, obj) mjs_get_ptr(mjs, mjs_get(mjs, obj, INST_PROP_NAME, ~0))
#define JS_GET_CONTEXT(mjs)   JS_GET_INST(mjs, mjs_get_this(mjs))
 
#define JS_ASSIGN_MULTI(mjs, object)     \
    for(struct {                         \
            struct mjs* mjs;             \
            mjs_val_t val;               \
            int i;                       \
        } _ass_multi = {mjs, object, 0}; \
        _ass_multi.i == 0;               \
        _ass_multi.i++)
#define JS_FIELD(name, value) mjs_set(_ass_multi.mjs, _ass_multi.val, name, ~0, value)
 
typedef enum {
    JsForeignMagicStart = 0x15BAD000,
    JsForeignMagic_JsEventLoopContract,
} JsForeignMagic;
 
// Are you tired of your silly little JS+C glue code functions being 75%
// argument validation code and 25% actual logic? Introducing: ASS (Argument
// Schema for Scripts)! ASS is a set of macros that reduce the typical
// boilerplate code of "check argument count, get arguments, validate arguments,
// extract C values from arguments" down to just one line!
 
#define JS_EXACTLY  ==
#define JS_AT_LEAST >=
 
typedef struct {
    const char* name;
    size_t value;
} JsEnumMapping;
 
#define JS_ENUM_MAP(var_name, ...)                      \
    static const JsEnumMapping var_name##_mapping[] = { \
        {NULL, sizeof(var_name)},                       \
        __VA_ARGS__,                                    \
        {NULL, 0},                                      \
    };
 
typedef struct {
    const char* name;
    size_t offset;
} JsObjectMapping;
 
#define JS_OBJ_MAP(var_name, ...)                         \
    static const JsObjectMapping var_name##_mapping[] = { \
        __VA_ARGS__,                                      \
        {NULL, 0},                                        \
    };
 
typedef struct {
    void* out;
    int (*validator)(mjs_val_t);
    void (*converter)(struct mjs*, mjs_val_t*, void* out, const void* extra);
    const char* expected_type;
    bool (*extended_validator)(struct mjs*, mjs_val_t, const void* extra);
    const void* extra_data;
} _js_arg_decl;
 
static inline void _js_to_int32(struct mjs* mjs, mjs_val_t* in, void* out, const void* extra) {
    UNUSED(extra);
    *(int32_t*)out = mjs_get_int32(mjs, *in);
}
#define JS_ARG_INT32(out) ((_js_arg_decl){out, mjs_is_number, _js_to_int32, "number", NULL, NULL})
 
static inline void _js_to_ptr(struct mjs* mjs, mjs_val_t* in, void* out, const void* extra) {
    UNUSED(extra);
    *(void**)out = mjs_get_ptr(mjs, *in);
}
#define JS_ARG_PTR(out) \
    ((_js_arg_decl){out, mjs_is_foreign, _js_to_ptr, "opaque pointer", NULL, NULL})
 
static inline void _js_to_string(struct mjs* mjs, mjs_val_t* in, void* out, const void* extra) {
    UNUSED(extra);
    *(const char**)out = mjs_get_string(mjs, in, NULL);
}
#define JS_ARG_STR(out) ((_js_arg_decl){out, mjs_is_string, _js_to_string, "string", NULL, NULL})
 
static inline void _js_to_bool(struct mjs* mjs, mjs_val_t* in, void* out, const void* extra) {
    UNUSED(extra);
    *(bool*)out = !!mjs_get_bool(mjs, *in);
}
#define JS_ARG_BOOL(out) ((_js_arg_decl){out, mjs_is_boolean, _js_to_bool, "boolean", NULL, NULL})
 
static inline void _js_passthrough(struct mjs* mjs, mjs_val_t* in, void* out, const void* extra) {
    UNUSED(extra);
    UNUSED(mjs);
    *(mjs_val_t*)out = *in;
}
#define JS_ARG_ANY(out) ((_js_arg_decl){out, NULL, _js_passthrough, "any", NULL, NULL})
#define JS_ARG_OBJ(out) ((_js_arg_decl){out, mjs_is_object, _js_passthrough, "any", NULL, NULL})
#define JS_ARG_FN(out) \
    ((_js_arg_decl){out, mjs_is_function, _js_passthrough, "function", NULL, NULL})
#define JS_ARG_ARR(out) ((_js_arg_decl){out, mjs_is_array, _js_passthrough, "array", NULL, NULL})
 
static inline bool _js_validate_struct(struct mjs* mjs, mjs_val_t val, const void* extra) {
    JsForeignMagic expected_magic = (JsForeignMagic)(size_t)extra;
    JsForeignMagic struct_magic = *(JsForeignMagic*)mjs_get_ptr(mjs, val);
    return struct_magic == expected_magic;
}
#define JS_ARG_STRUCT(type, out) \
    ((_js_arg_decl){             \
        out,                     \
        mjs_is_foreign,          \
        _js_to_ptr,              \
        #type,                   \
        _js_validate_struct,     \
        (void*)JsForeignMagic##_##type})
 
static inline bool _js_validate_obj_w_struct(struct mjs* mjs, mjs_val_t val, const void* extra) {
    JsForeignMagic expected_magic = (JsForeignMagic)(size_t)extra;
    JsForeignMagic struct_magic = *(JsForeignMagic*)JS_GET_INST(mjs, val);
    return struct_magic == expected_magic;
}
#define JS_ARG_OBJ_WITH_STRUCT(type, out) \
    ((_js_arg_decl){                      \
        out,                              \
        mjs_is_object,                    \
        _js_passthrough,                  \
        #type,                            \
        _js_validate_obj_w_struct,        \
        (void*)JsForeignMagic##_##type})
 
static inline bool _js_validate_enum(struct mjs* mjs, mjs_val_t val, const void* extra) {
    for(const JsEnumMapping* mapping = (JsEnumMapping*)extra + 1; mapping->name; mapping++)
        if(strcmp(mapping->name, mjs_get_string(mjs, &val, NULL)) == 0) return true;
    return false;
}
static inline void
    _js_convert_enum(struct mjs* mjs, mjs_val_t* val, void* out, const void* extra) {
    const JsEnumMapping* mapping = (JsEnumMapping*)extra;
    size_t size = mapping->value; // get enum size from first entry
    for(mapping++; mapping->name; mapping++) {
        if(strcmp(mapping->name, mjs_get_string(mjs, val, NULL)) == 0) {
            if(size == 1)
                *(uint8_t*)out = mapping->value;
            else if(size == 2)
                *(uint16_t*)out = mapping->value;
            else if(size == 4)
                *(uint32_t*)out = mapping->value;
            else if(size == 8)
                *(uint64_t*)out = mapping->value;
            return;
        }
    }
    // unreachable, thanks to _js_validate_enum
}
#define JS_ARG_ENUM(var_name, name) \
    ((_js_arg_decl){                \
        &var_name,                  \
        mjs_is_string,              \
        _js_convert_enum,           \
        name " enum",               \
        _js_validate_enum,          \
        var_name##_mapping})
 
static inline bool _js_validate_object(struct mjs* mjs, mjs_val_t val, const void* extra) {
    for(const JsObjectMapping* mapping = (JsObjectMapping*)extra; mapping->name; mapping++)
        if(mjs_get(mjs, val, mapping->name, ~0) == MJS_UNDEFINED) return false;
    return true;
}
static inline void
    _js_convert_object(struct mjs* mjs, mjs_val_t* val, void* out, const void* extra) {
    const JsObjectMapping* mapping = (JsObjectMapping*)extra;
    for(; mapping->name; mapping++) {
        mjs_val_t field_val = mjs_get(mjs, *val, mapping->name, ~0);
        *(mjs_val_t*)((uint8_t*)out + mapping->offset) = field_val;
    }
}
#define JS_ARG_OBJECT(var_name, name) \
    ((_js_arg_decl){                  \
        &var_name,                    \
        mjs_is_object,                \
        _js_convert_object,           \
        name " object",               \
        _js_validate_object,          \
        var_name##_mapping})
 
#define JS_CONVERT_OR_RETURN(mjs, value, decl, source, ...)        \
    if(decl.validator)                                             \
        if(!decl.validator(*value))                                \
            JS_ERROR_AND_RETURN(                                   \
                mjs,                                               \
                MJS_BAD_ARGS_ERROR,                                \
                source ": expected %s",                            \
                ##__VA_ARGS__,                                     \
                decl.expected_type);                               \
    if(decl.extended_validator)                                    \
        if(!decl.extended_validator(mjs, *value, decl.extra_data)) \
            JS_ERROR_AND_RETURN(                                   \
                mjs,                                               \
                MJS_BAD_ARGS_ERROR,                                \
                source ": expected %s",                            \
                ##__VA_ARGS__,                                     \
                decl.expected_type);                               \
    decl.converter(mjs, value, decl.out, decl.extra_data);
 
//-V:JS_FETCH_ARGS_OR_RETURN:1008
#define JS_FETCH_ARGS_OR_RETURN(mjs, arg_operator, ...)                                \
    _js_arg_decl _js_args[] = {__VA_ARGS__};                                           \
    int _js_arg_cnt = COUNT_OF(_js_args);                                              \
    mjs_val_t _js_arg_vals[_js_arg_cnt];                                               \
    if(!(mjs_nargs(mjs) arg_operator _js_arg_cnt))                                     \
        JS_ERROR_AND_RETURN(                                                           \
            mjs,                                                                       \
            MJS_BAD_ARGS_ERROR,                                                        \
            "expected %s%d arguments, got %d",                                         \
            #arg_operator,                                                             \
            _js_arg_cnt,                                                               \
            mjs_nargs(mjs));                                                           \
    for(int _i = 0; _i < _js_arg_cnt; _i++) {                                          \
        _js_arg_vals[_i] = mjs_arg(mjs, _i);                                           \
        JS_CONVERT_OR_RETURN(mjs, &_js_arg_vals[_i], _js_args[_i], "argument %d", _i); \
    }
 
#define JS_ERROR_AND_RETURN(mjs, error_code, ...)         \
    do {                                                  \
        mjs_prepend_errorf(mjs, error_code, __VA_ARGS__); \
        mjs_return(mjs, MJS_UNDEFINED);                   \
        return;                                           \
    } while(0)
 
#define JS_ERROR_AND_RETURN_VAL(mjs, error_code, ret_val, ...) \
    do {                                                       \
        mjs_prepend_errorf(mjs, error_code, __VA_ARGS__);      \
        mjs_return(mjs, MJS_UNDEFINED);                        \
        return ret_val;                                        \
    } while(0)
 
typedef struct JsModules JsModules;
 
typedef void* (*JsModuleConstructor)(struct mjs* mjs, mjs_val_t* object, JsModules* modules);
typedef void (*JsModuleDestructor)(void* inst);
 
typedef struct {
    char* name;
    JsModuleConstructor create;
    JsModuleDestructor destroy;
    const ElfApiInterface* api_interface;
} JsModuleDescriptor;
 
JsModules* js_modules_create(struct mjs* mjs, CompositeApiResolver* resolver);
 
void js_modules_destroy(JsModules* modules);
 
mjs_val_t js_module_require(JsModules* modules, const char* name, size_t name_len);
 
void* js_module_get(JsModules* modules, const char* name);
 
void js_sdk_compatibility_status(struct mjs* mjs);
 
void js_is_sdk_compatible(struct mjs* mjs);
 
void js_check_sdk_compatibility(struct mjs* mjs);
 
void js_does_sdk_support(struct mjs* mjs);
 
void js_check_sdk_features(struct mjs* mjs);