jni/ruby/eval_jump.c


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

/* -*-c-*- */
/*
 * from eval.c
 */

#include "eval_intern.h"

/* exit */

void
rb_call_end_proc(VALUE data)
{
    rb_proc_call(data, rb_ary_new());
}

/*
 *  call-seq:
 *     at_exit { block } -> proc
 *
 *  Converts _block_ to a +Proc+ object (and therefore
 *  binds it at the point of call) and registers it for execution when
 *  the program exits. If multiple handlers are registered, they are
 *  executed in reverse order of registration.
 *
 *     def do_at_exit(str1)
 *       at_exit { print str1 }
 *     end
 *     at_exit { puts "cruel world" }
 *     do_at_exit("goodbye ")
 *     exit
 *
 *  <em>produces:</em>
 *
 *     goodbye cruel world
 */

static VALUE
rb_f_at_exit(void)
{
    VALUE proc;

    if (!rb_block_given_p()) {
        rb_raise(rb_eArgError, "called without a block");
    }
    proc = rb_block_proc();
    rb_set_end_proc(rb_call_end_proc, proc);
    return proc;
}

struct end_proc_data {
    void (*func) ();
    VALUE data;
    int safe;
    struct end_proc_data *next;
};

static struct end_proc_data *end_procs, *ephemeral_end_procs;

void
rb_set_end_proc(void (*func)(VALUE), VALUE data)
{
    struct end_proc_data *link = ALLOC(struct end_proc_data);
    struct end_proc_data **list;
    rb_thread_t *th = GET_THREAD();

    if (th->top_wrapper) {
        list = &ephemeral_end_procs;
    }
    else {
        list = &end_procs;
    }
    link->next = *list;
    link->func = func;
    link->data = data;
    link->safe = rb_safe_level();
    *list = link;
}

void
rb_mark_end_proc(void)
{
    struct end_proc_data *link;

    link = end_procs;
    while (link) {
        rb_gc_mark(link->data);
        link = link->next;
    }
    link = ephemeral_end_procs;
    while (link) {
        rb_gc_mark(link->data);
        link = link->next;
    }
}

static void
exec_end_procs_chain(struct end_proc_data *volatile *procs)
{
    struct end_proc_data volatile endproc;
    struct end_proc_data *link;

    while ((link = *procs) != 0) {
        *procs = link->next;
        endproc = *link;
        xfree(link);
        rb_set_safe_level_force(endproc.safe);
        (*endproc.func) (endproc.data);
    }
}

void
rb_exec_end_proc(void)
{
    int status;
    volatile int safe = rb_safe_level();
    rb_thread_t *th = GET_THREAD();
    volatile VALUE errinfo = th->errinfo;

    PUSH_TAG();
    if ((status = EXEC_TAG()) == 0) {
      again:
        exec_end_procs_chain(&ephemeral_end_procs);
        exec_end_procs_chain(&end_procs);
    }
    else {
        VAR_INITIALIZED(th);
        TH_TMPPOP_TAG();
        error_handle(status);
        if (!NIL_P(th->errinfo)) errinfo = th->errinfo;
        TH_REPUSH_TAG();
        goto again;
    }
    POP_TAG();

    rb_set_safe_level_force(safe);
    th->errinfo = errinfo;
}

void
Init_jump(void)
{
    rb_define_global_function("at_exit", rb_f_at_exit, 0);
}