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
|
#include "get-drvs.hh"
#include "util.hh"
namespace nix {
string DrvInfo::queryDrvPath(EvalState & state) const
{
if (drvPath == "" && attrs) {
Bindings::iterator i = attrs->find(state.sDrvPath);
PathSet context;
(string &) drvPath = i != attrs->end() ? state.coerceToPath(*i->value, context) : "";
}
return drvPath;
}
string DrvInfo::queryOutPath(EvalState & state) const
{
if (outPath == "" && attrs) {
Bindings::iterator i = attrs->find(state.sOutPath);
PathSet context;
(string &) outPath = i != attrs->end() ? state.coerceToPath(*i->value, context) : "";
}
return outPath;
}
MetaInfo DrvInfo::queryMetaInfo(EvalState & state) const
{
if (metaInfoRead) return meta;
(bool &) metaInfoRead = true;
Bindings::iterator a = attrs->find(state.sMeta);
if (a == attrs->end()) return meta; /* fine, empty meta information */
state.forceAttrs(*a->value);
foreach (Bindings::iterator, i, *a->value->attrs) {
MetaValue value;
state.forceValue(*i->value);
if (i->value->type == tString) {
value.type = MetaValue::tpString;
value.stringValue = i->value->string.s;
} else if (i->value->type == tInt) {
value.type = MetaValue::tpInt;
value.intValue = i->value->integer;
} else if (i->value->type == tList) {
value.type = MetaValue::tpStrings;
for (unsigned int j = 0; j < i->value->list.length; ++j)
value.stringValues.push_back(state.forceStringNoCtx(*i->value->list.elems[j]));
} else continue;
((MetaInfo &) meta)[i->name] = value;
}
return meta;
}
MetaValue DrvInfo::queryMetaInfo(EvalState & state, const string & name) const
{
/* !!! evaluates all meta attributes => inefficient */
return queryMetaInfo(state)[name];
}
void DrvInfo::setMetaInfo(const MetaInfo & meta)
{
metaInfoRead = true;
this->meta = meta;
}
/* Cache for already considered attrsets. */
typedef set<Bindings *> Done;
/* Evaluate value `v'. If it evaluates to an attribute set of type
`derivation', then put information about it in `drvs' (unless it's
already in `doneExprs'). The result boolean indicates whether it
makes sense for the caller to recursively search for derivations in
`v'. */
static bool getDerivation(EvalState & state, Value & v,
const string & attrPath, DrvInfos & drvs, Done & done)
{
try {
state.forceValue(v);
if (!state.isDerivation(v)) return true;
/* Remove spurious duplicates (e.g., an attribute set like
`rec { x = derivation {...}; y = x;}'. */
if (done.find(v.attrs) != done.end()) return false;
done.insert(v.attrs);
DrvInfo drv;
Bindings::iterator i = v.attrs->find(state.sName);
/* !!! We really would like to have a decent back trace here. */
if (i == v.attrs->end()) throw TypeError("derivation name missing");
drv.name = state.forceStringNoCtx(*i->value);
Bindings::iterator i2 = v.attrs->find(state.sSystem);
if (i2 == v.attrs->end())
drv.system = "unknown";
else
drv.system = state.forceStringNoCtx(*i2->value);
drv.attrs = v.attrs;
drv.attrPath = attrPath;
drvs.push_back(drv);
return false;
} catch (AssertionError & e) {
return false;
}
}
bool getDerivation(EvalState & state, Value & v, DrvInfo & drv)
{
Done done;
DrvInfos drvs;
getDerivation(state, v, "", drvs, done);
if (drvs.size() != 1) return false;
drv = drvs.front();
return true;
}
static string addToPath(const string & s1, const string & s2)
{
return s1.empty() ? s2 : s1 + "." + s2;
}
static void getDerivations(EvalState & state, Value & vIn,
const string & pathPrefix, Bindings & autoArgs,
DrvInfos & drvs, Done & done)
{
Value v;
state.autoCallFunction(autoArgs, vIn, v);
/* Process the expression. */
DrvInfo drv;
if (!getDerivation(state, v, pathPrefix, drvs, done)) ;
else if (v.type == tAttrs) {
/* !!! undocumented hackery to support combining channels in
nix-env.cc. */
bool combineChannels = v.attrs->find(state.symbols.create("_combineChannels")) != v.attrs->end();
/* Consider the attributes in sorted order to get more
deterministic behaviour in nix-env operations (e.g. when
there are names clashes between derivations, the derivation
bound to the attribute with the "lower" name should take
precedence). */
typedef std::map<string, Symbol> SortedSymbols;
SortedSymbols attrs;
foreach (Bindings::iterator, i, *v.attrs)
attrs.insert(std::pair<string, Symbol>(i->name, i->name));
foreach (SortedSymbols::iterator, i, attrs) {
startNest(nest, lvlDebug, format("evaluating attribute `%1%'") % i->first);
string pathPrefix2 = addToPath(pathPrefix, i->first);
Value & v2(*(*v.attrs)[i->second].value);
if (combineChannels)
getDerivations(state, v2, pathPrefix2, autoArgs, drvs, done);
else if (getDerivation(state, v2, pathPrefix2, drvs, done)) {
/* If the value of this attribute is itself an
attribute set, should we recurse into it? => Only
if it has a `recurseForDerivations = true'
attribute. */
if (v2.type == tAttrs) {
Bindings::iterator j = v2.attrs->find(state.symbols.create("recurseForDerivations"));
if (j != v2.attrs->end() && state.forceBool(*j->value))
getDerivations(state, v2, pathPrefix2, autoArgs, drvs, done);
}
}
}
}
else if (v.type == tList) {
for (unsigned int n = 0; n < v.list.length; ++n) {
startNest(nest, lvlDebug,
format("evaluating list element"));
string pathPrefix2 = addToPath(pathPrefix, (format("%1%") % n).str());
if (getDerivation(state, *v.list.elems[n], pathPrefix2, drvs, done))
getDerivations(state, *v.list.elems[n], pathPrefix2, autoArgs, drvs, done);
}
}
else throw TypeError("expression does not evaluate to a derivation (or a set or list of those)");
}
void getDerivations(EvalState & state, Value & v, const string & pathPrefix,
Bindings & autoArgs, DrvInfos & drvs)
{
Done done;
getDerivations(state, v, pathPrefix, autoArgs, drvs, done);
}
}
|
