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
|
/*
Copyright (C) 2006 Vincent Fourmond
Symbols is free software; you can redistribute it and/or modify
it under the terms of the GNU General Library Public License as published
by the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
Symbols is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Library General Public License for more details.
You should have received a copy of the GNU Library General Public License
along with Dvector; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/* Simple code for sharing C symbols across different Ruby libraries */
#include <ruby.h>
#include <intern.h>
#include <namespace.h>
/* MV stands for Module Variable */
#define MV_SYMBOLS "@_exported_C_symbols"
/* modified to use instance variables instead of global class variables:
this way, children don't overwrite the parent's export table
*/
/* makes sure that the hash is registered for the given
module and returns it */
static VALUE get_symbol_hash(VALUE module)
{
VALUE hash;
ID mv_id = rb_intern(MV_SYMBOLS);
if(RTEST(rb_ivar_defined(module, mv_id)))
return rb_ivar_get(module, mv_id);
else
{
/* module variable uninitialized, we need to make sure it's here */
hash = rb_hash_new();
rb_ivar_set(module, mv_id, hash);
return hash;
}
}
/* registers a symbol in the given module. This one is the internal
function */
PRIVATE void rb_export_symbol(VALUE module, const char * symbol_name,
void * symbol)
{
VALUE hash = get_symbol_hash(module);
rb_hash_aset(hash, rb_str_new2(symbol_name),LONG2NUM((long) symbol));
}
PRIVATE void * rb_import_symbol_no_raise(VALUE module,
const char * symbol_name)
{
VALUE hash = rb_iv_get(module, MV_SYMBOLS);
VALUE symbol = rb_hash_aref(hash, rb_str_new2(symbol_name));
if(TYPE(symbol) == T_FIXNUM || TYPE(symbol) == T_BIGNUM)
return (void *) NUM2LONG(symbol);
return NULL;
}
/* same as before, but raises something is the return value is NULL,
which is probably best as a default behavior*/
PRIVATE void * rb_import_symbol(VALUE module, const char * symbol_name)
{
void * symbol = rb_import_symbol_no_raise(module, symbol_name);
if(symbol)
return symbol;
/* we get the name of the module: */
VALUE module_name = rb_funcall(module, rb_intern("to_s"), 0);
rb_raise(rb_eRuntimeError, "The symbol %s was not found in "
"module %s", symbol_name,
rb_string_value_cstr(&module_name));
}
|
