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
|
#include "json-to-value.hh"
#include <cstring>
namespace nix {
static void skipWhitespace(const char*& s) {
while (*s == ' ' || *s == '\t' || *s == '\n' || *s == '\r') s++;
}
static string parseJSONString(const char*& s) {
string res;
if (*s++ != '"') throw JSONParseError("expected JSON string");
while (*s != '"') {
if (!*s) throw JSONParseError("got end-of-string in JSON string");
if (*s == '\\') {
s++;
if (*s == '"')
res += '"';
else if (*s == '\\')
res += '\\';
else if (*s == '/')
res += '/';
else if (*s == '/')
res += '/';
else if (*s == 'b')
res += '\b';
else if (*s == 'f')
res += '\f';
else if (*s == 'n')
res += '\n';
else if (*s == 'r')
res += '\r';
else if (*s == 't')
res += '\t';
else if (*s == 'u')
throw JSONParseError(
"\\u characters in JSON strings are currently not supported");
else
throw JSONParseError("invalid escaped character in JSON string");
s++;
} else
res += *s++;
}
s++;
return res;
}
static void parseJSON(EvalState& state, const char*& s, Value& v) {
skipWhitespace(s);
if (!*s) throw JSONParseError("expected JSON value");
if (*s == '[') {
s++;
ValueVector values;
values.reserve(128);
skipWhitespace(s);
while (1) {
if (values.empty() && *s == ']') break;
Value* v2 = state.allocValue();
parseJSON(state, s, *v2);
values.push_back(v2);
skipWhitespace(s);
if (*s == ']') break;
if (*s != ',')
throw JSONParseError("expected ',' or ']' after JSON array element");
s++;
}
s++;
state.mkList(v, values.size());
for (size_t n = 0; n < values.size(); ++n) v.listElems()[n] = values[n];
}
else if (*s == '{') {
s++;
ValueMap attrs;
while (1) {
skipWhitespace(s);
if (attrs.empty() && *s == '}') break;
string name = parseJSONString(s);
skipWhitespace(s);
if (*s != ':') throw JSONParseError("expected ':' in JSON object");
s++;
Value* v2 = state.allocValue();
parseJSON(state, s, *v2);
attrs[state.symbols.create(name)] = v2;
skipWhitespace(s);
if (*s == '}') break;
if (*s != ',')
throw JSONParseError("expected ',' or '}' after JSON member");
s++;
}
state.mkAttrs(v, attrs.size());
for (auto& i : attrs) v.attrs->push_back(Attr(i.first, i.second));
v.attrs->sort();
s++;
}
else if (*s == '"') {
mkString(v, parseJSONString(s));
}
else if (isdigit(*s) || *s == '-' || *s == '.') {
// Buffer into a string first, then use built-in C++ conversions
std::string tmp_number;
ValueType number_type = tInt;
while (isdigit(*s) || *s == '-' || *s == '.' || *s == 'e' || *s == 'E') {
if (*s == '.' || *s == 'e' || *s == 'E') number_type = tFloat;
tmp_number += *s++;
}
try {
if (number_type == tFloat)
mkFloat(v, stod(tmp_number));
else
mkInt(v, stol(tmp_number));
} catch (std::invalid_argument& e) {
throw JSONParseError("invalid JSON number");
} catch (std::out_of_range& e) {
throw JSONParseError("out-of-range JSON number");
}
}
else if (strncmp(s, "true", 4) == 0) {
s += 4;
mkBool(v, true);
}
else if (strncmp(s, "false", 5) == 0) {
s += 5;
mkBool(v, false);
}
else if (strncmp(s, "null", 4) == 0) {
s += 4;
mkNull(v);
}
else
throw JSONParseError("unrecognised JSON value");
}
void parseJSON(EvalState& state, const string& s_, Value& v) {
const char* s = s_.c_str();
parseJSON(state, s, v);
skipWhitespace(s);
if (*s)
throw JSONParseError(
format("expected end-of-string while parsing JSON value: %1%") % s);
}
} // namespace nix
|
