emojicode/
lib.rs

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
#![feature(pointer_methods)]

extern crate emojicode_sys;

pub use emojicode_sys::*;
use std::ffi::{CStr, CString};
use std::ptr;

/// Given the major and minor version this generate the package version.
/// 
/// Example:
/// ```rust
/// package_version!(0, 1);
/// ```
#[macro_export]
macro_rules! package_version {
    ($maj:expr, $min:expr) => {
        #[no_mangle]
        #[allow(non_upper_case_globals)]
        pub static version: Emojicode_PackageVersion = Emojicode_PackageVersion { major: $maj, minor: $min };
    };
}

/// Shorthand for defining functions compatible with the linking table, and an accompanying linking
/// table.
/// 
/// Example:
/// ```rust
/// emoji_functions!(
///     hello_world(thread) {
///         println!("Hello from Rust!");
///         thread.return_from_function();
///     }
/// );
/// ```
#[macro_export]
macro_rules! emoji_functions {
    (
        $($name:ident ($t:ident) $b:block),+
    ) => {
        $(
            unsafe extern "C" fn $name($t : *mut Emojicode_Thread) $b
        )+
        linking_table!($($name),+);
    }
}

/// Used for the "prepareClass" shenanigans. I suggest you look up the emojicode docs in order to 
/// figure out what to do here.
/// 
/// Example:
/// ```rust
/// prepare_class!(
///     (class, name) {
///         // do stuff here
///     }
/// );
#[macro_export]
macro_rules! prepare_class {
    (($arg1:ident, $arg2:ident) $b:block) => {
        #[no_mangle]
        #[allow(unused_variables)]
        pub unsafe extern "C" fn prepareClass($arg1: *mut Emojicode_Class, $arg2: EmojicodeChar) $b
    }
}

#[macro_export]
macro_rules! linking_table {
    ($($idents:ident),+) => {
        #[no_mangle]
        #[allow(non_upper_case_globals)]
        pub static linkingTable: [Emojicode_FunctionFunctionPointer; count_args_space!($($idents)*) +1] = [None, $(Some($idents)),+];
    }
}

#[macro_export]
macro_rules! count_args_space {
    ($name:ident) => { 1 };
    ($first:ident $($rest:ident) *) => {
        1 + count_args_space!($($rest) *)
    }
}

/// Converts Rust types to Emojicode Values. Useful for example for returning things from a 
/// function.
pub trait ToValue {
    fn to_value(self) -> Option<Emojicode_Value>;
}

pub trait FromValue<T> {
    fn from_value(self) -> T;
}

impl FromValue<String> for Emojicode_Value {
    fn from_value(self) -> String {
        unsafe {
            let obj_ptr = &emojicode_sys::Emojicode_stringToCString(
                self.object
            );
            CStr::from_ptr(*obj_ptr).to_string_lossy().into_owned()
        }
    }
}

impl ToValue for String {
    fn to_value(self) -> Option<Emojicode_Value> {
        let the_string = CString::new(self);
        match the_string {
            Ok(c) => unsafe {
                Some(Emojicode_Value {
                    object: Emojicode_stringFromChar(c.as_ptr()),
                })
            },
            Err(_) => None,
        }
    }
}

impl ToValue for *mut Emojicode_Object {
    fn to_value(self) -> Option<Emojicode_Value> {
        Some(Emojicode_Value { object: self })
    }
}

pub trait EmojicodeThreadImpl {
    unsafe fn return_from_function(self);
    unsafe fn return_from_function_with_value(self, value: Emojicode_Value);
    //unsafe fn variableDestination(self, index: usize) -> Emojicode_Value;
    unsafe fn variable(self, index: usize) -> Emojicode_Value;
    unsafe fn this_object(self) -> *mut Emojicode_Object;
}

impl EmojicodeThreadImpl for *mut Emojicode_Thread {
    unsafe fn return_from_function(self) {
        let p: *mut u32 = ptr::null_mut();
        (*(*self).stack_).executionPointer = p;
    }

    unsafe fn return_from_function_with_value(self, value: Emojicode_Value) {
        *(*(*self).stack_).destination = value;
        self.return_from_function();
    }

    unsafe fn variable(self, index: usize) -> Emojicode_Value {
        let pt: *const Emojicode_Value = &(*(*self).stack_).thisContext;
        *pt.add(index + 1) as Emojicode_Value
    }

    unsafe fn this_object(self) -> *mut Emojicode_Object {
        (*(*self).stack_).thisContext.object
    }

/*    unsafe fn variableDestination(self, index: usize) -> Emojicode_Value {
        (*(*self).stack_).variableDestination(index)
    }*/

}

pub trait EmojicodeObjectImpl {
    unsafe fn value<T>(self) -> *mut T;
}

impl EmojicodeObjectImpl for *mut Emojicode_Object {
    unsafe fn value<T>(self) -> *mut T {
        self.add(1) as *mut T
    }
}