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

use rubysys::libc::size_t;
use std::mem;

use rubysys::constant::{FL_USHIFT, FL_USER_1, FL_USER_3, FL_USER_4};
use rubysys::types::{c_long, InternalValue, RBasic, Value};

extern "C" {
    // VALUE
    // rb_ary_concat(VALUE x, VALUE y)
    pub fn rb_ary_concat(array: Value, other_array: Value) -> Value;
    // VALUE
    // rb_ary_dup(VALUE ary)
    pub fn rb_ary_dup(array: Value) -> Value;
    // VALUE
    // rb_ary_entry(VALUE ary, long offset)
    pub fn rb_ary_entry(array: Value, offset: c_long) -> Value;
    // VALUE
    // rb_ary_join(VALUE ary, VALUE sep)
    pub fn rb_ary_join(array: Value, separator: Value) -> Value;
    // VALUE
    // rb_ary_new(void)
    pub fn rb_ary_new() -> Value;
    // VALUE
    // rb_ary_new_from_values(long n, const VALUE *elts)
    pub fn rb_ary_new_from_values(count: c_long, elements: *const Value) -> Value;
    // VALUE
    // rb_ary_new_capa(long capa)
    pub fn rb_ary_new_capa(capacity: c_long) -> Value;
    // VALUE
    // rb_ary_pop(VALUE ary)
    pub fn rb_ary_pop(array: Value) -> Value;
    // VALUE
    // rb_ary_push(VALUE ary, VALUE item)
    pub fn rb_ary_push(array: Value, item: Value) -> Value;
    // VALUE
    // rb_ary_reverse(VALUE ary)
    pub fn rb_ary_reverse(array: Value) -> Value;
    // VALUE
    // rb_ary_shift(VALUE ary)
    pub fn rb_ary_shift(array: Value) -> Value;
    // VALUE
    // rb_ary_sort_bang(VALUE ary)
    pub fn rb_ary_sort_bang(array: Value) -> Value;
    // VALUE
    // rb_ary_sort(VALUE ary)
    pub fn rb_ary_sort(array: Value) -> Value;
    // void
    // rb_ary_store(VALUE ary, long idx, VALUE val)
    pub fn rb_ary_store(array: Value, index: c_long, item: Value);
    // VALUE
    // rb_ary_to_s(VALUE ary)
    pub fn rb_ary_to_s(array: Value) -> Value;
    // VALUE
    // rb_ary_unshift(VALUE ary, VALUE item)
    pub fn rb_ary_unshift(array: Value, item: Value) -> Value;
}

#[derive(Debug, PartialEq)]
#[link_name = "ruby_rarray_flags"]
#[repr(C)]
enum RArrayEmbed {
    LenMax = 3,
    Flag = FL_USER_1,
    LenMask = FL_USER_4 | FL_USER_3,
    LenShift = FL_USHIFT + 3,
}

#[repr(C)]
struct RArrayAs {
    heap: RArrayHeap,
}

#[repr(C)]
struct RArrayHeap {
    len: c_long,
    // Really, this is a union but value is the largest item.
    value: InternalValue,
    ptr: InternalValue,
}

#[repr(C)]
struct RArray {
    basic: RBasic,
    as_: RArrayAs,
}

pub unsafe fn rb_ary_len(value: Value) -> c_long {
    let rarray: *const RArray = mem::transmute(value.value);
    let flags = (*rarray).basic.flags;

    if flags & (RArrayEmbed::Flag as size_t) == 0 {
        (*rarray).as_.heap.len
    } else {
        ((flags as i64 >> RArrayEmbed::LenShift as i64) &
         (RArrayEmbed::LenMask as i64 >> RArrayEmbed::LenShift as i64)) as c_long
    }
}