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
|
// file : libbuild2/config/utility.txx -*- C++ -*-
// license : MIT; see accompanying LICENSE file
#include <libbuild2/scope.hxx>
#include <libbuild2/context.hxx> // current_mif
namespace build2
{
namespace config
{
template <typename T>
pair<lookup, bool>
required (scope& rs,
const variable& var,
T&& def_val,
bool def_ovr,
uint64_t sflags)
{
// Note: see also omitted() if changing anything here.
save_variable (rs, var, sflags);
pair<lookup, size_t> org (rs.find_original (var));
bool n (false); // New flag.
lookup l (org.first);
// The interaction with command line overrides can get tricky. For
// example, the override to default value could make (non-recursive)
// command line override in the outer scope no longer apply. So what we
// are going to do is first ignore overrides and perform the normal
// logic on the original. Then we apply the overrides on the result.
//
if (!l.defined () || (def_ovr && !l.belongs (rs)))
{
value& v (rs.assign (var) = std::forward<T> (def_val)); // VC14
v.extra = true; // Default value flag.
n = (sflags & save_default_commented) == 0; // Absence means default.
l = lookup (v, var, rs);
org = make_pair (l, 1); // Lookup depth is 1 since it's in rs.vars.
}
// Treat an inherited value that was set to default as new.
//
else if (l->extra)
n = (sflags & save_default_commented) == 0; // Absence means default.
if (var.overrides != nullptr)
{
pair<lookup, size_t> ovr (rs.find_override (var, move (org)));
if (l != ovr.first) // Overriden?
{
// Override is always treated as new.
//
n = true;
l = move (ovr.first);
}
}
return pair<lookup, bool> (l, n);
}
}
}
|
