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
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
// file : libbuild2/rule.hxx -*- C++ -*-
// license : MIT; see accompanying LICENSE file
#ifndef LIBBUILD2_RULE_HXX
#define LIBBUILD2_RULE_HXX
#include <libbuild2/types.hxx>
#include <libbuild2/forward.hxx>
#include <libbuild2/utility.hxx>
#include <libbuild2/action.hxx>
#include <libbuild2/target.hxx>
#include <libbuild2/recipe.hxx>
#include <libbuild2/export.hxx>
namespace build2
{
// Rule interface (see also simple_rule below for a simplified version).
//
// Once a rule is registered (for a scope), it is treated as immutable. If
// you need to modify some state (e.g., counters or some such), then make
// sure things are MT-safe.
//
// Note: match() is only called once but may not be followed by apply().
//
// The match_extra argument is used to pass additional information that is
// only needed by some rule implementations. It is also a way for us to
// later pass more information without breaking source compatibility.
//
struct match_extra
{
};
class LIBBUILD2_SYMEXPORT rule
{
public:
virtual bool
match (action, target&, const string& hint, match_extra&) const = 0;
virtual recipe
apply (action, target&, match_extra&) const = 0;
rule () = default;
virtual
~rule ();
rule (const rule&) = delete;
rule& operator= (const rule&) = delete;
};
// Simplified interface for rules that don't care about the extras.
//
class LIBBUILD2_SYMEXPORT simple_rule: public rule
{
public:
virtual bool
match (action, target&, const string& hint) const = 0;
virtual recipe
apply (action, target&) const = 0;
virtual bool
match (action, target&, const string&, match_extra&) const override;
virtual recipe
apply (action, target&, match_extra&) const override;
};
// Fallback rule that only matches if the file exists. It will also match
// an mtime_target provided it has a set timestamp.
//
class LIBBUILD2_SYMEXPORT file_rule: public simple_rule
{
public:
virtual bool
match (action, target&, const string&) const override;
virtual recipe
apply (action, target&) const override;
file_rule () {}
static const file_rule instance;
static const build2::rule_match rule_match;
};
class LIBBUILD2_SYMEXPORT alias_rule: public simple_rule
{
public:
virtual bool
match (action, target&, const string&) const override;
virtual recipe
apply (action, target&) const override;
alias_rule () {}
static const alias_rule instance;
};
// Note that this rule ignores the dry_run flag; see mkdir() in filesystem
// for the rationale.
//
class LIBBUILD2_SYMEXPORT fsdir_rule: public simple_rule
{
public:
virtual bool
match (action, target&, const string&) const override;
virtual recipe
apply (action, target&) const override;
static target_state
perform_update (action, const target&);
static target_state
perform_clean (action, const target&);
// Sometimes, as an optimization, we want to emulate execute_direct()
// of fsdir{} without the overhead of switching to the execute phase.
//
static void
perform_update_direct (action, const target&);
fsdir_rule () {}
static const fsdir_rule instance;
};
// Fallback rule that always matches and does nothing.
//
class LIBBUILD2_SYMEXPORT noop_rule: public simple_rule
{
public:
virtual bool
match (action, target&, const string&) const override;
virtual recipe
apply (action, target&) const override;
noop_rule () {}
static const noop_rule instance;
};
// Ad hoc rule.
//
// Note: not exported.
//
class adhoc_rule: public rule
{
public:
location_value loc; // Buildfile location of the recipe.
size_t braces; // Number of braces in multi-brace tokens.
adhoc_rule (const char* name, const location& l, size_t b)
: loc (l),
braces (b),
rule_match (name, static_cast<const rule&> (*this)) {}
// Set the rule text, handle any recipe-specific attributes, and return
// true if the recipe builds anything in the build/recipes/ directory and
// therefore requires cleanup.
//
// Target is not NULL only if this recipe is for a single target. Scope is
// the scope of the recipe (not necessarily the same as the target's base
// scope).
//
virtual bool
recipe_text (context&, const scope&, const target*, const adhoc_actions&,
string&&, attributes&) = 0;
public:
// Some of the operations come in compensating pairs, such as update and
// clean, install and uninstall. An ad hoc rule implementation may choose
// to provide a fallback implementation of a compensating operation if it
// is providing the other half (passed in the fallback argument).
//
// The default implementation calls rule::match() if fallback is absent
// and returns false if fallback is present. So an implementation that
// doesn't care about this semantics can implement the straight rule
// interface.
//
virtual bool
match (action, target&, const string&, match_extra&,
optional<action> fallback) const;
virtual bool
match (action, target&, const string&, match_extra&) const override;
// Dump support.
//
virtual void
dump_attributes (ostream&) const;
virtual void
dump_text (ostream&, string& indentation) const = 0;
// Implementation details.
//
public:
// The name in rule_match is used as a hint and as a name in diagnostics.
// The former does not apply to us (but will apply to ad hoc rules) while
// latter does. As a result, we use special-looking "<ad hoc X recipe>"
// names.
//
const build2::rule_match rule_match;
static const dir_path recipes_build_dir;
// Scope operation callback that cleans up ad hoc recipe builds.
//
static target_state
clean_recipes_build (action, const scope&, const dir&);
};
// A mix-in interface for ad hoc rules that support recipes with deadlines.
//
class adhoc_rule_with_deadline
{
public:
virtual
~adhoc_rule_with_deadline ();
// Return empty recipe if one with the deadline cannot be provided for
// this action. In this case the caller may fallback to the normal
// apply().
//
virtual recipe
apply (action, target&, match_extra&, const optional<timestamp>&) const = 0;
};
}
#endif // LIBBUILD2_RULE_HXX
|
