1 | /* JSON trees |
2 | Copyright (C) 2017-2024 Free Software Foundation, Inc. |
3 | Contributed by David Malcolm <dmalcolm@redhat.com>. |
4 | |
5 | This file is part of GCC. |
6 | |
7 | GCC is free software; you can redistribute it and/or modify it under |
8 | the terms of the GNU General Public License as published by the Free |
9 | Software Foundation; either version 3, or (at your option) any later |
10 | version. |
11 | |
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
15 | for more details. |
16 | |
17 | You should have received a copy of the GNU General Public License |
18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ |
20 | |
21 | #ifndef GCC_JSON_H |
22 | #define GCC_JSON_H |
23 | |
24 | /* Implementation of JSON, a lightweight data-interchange format. |
25 | |
26 | See http://www.json.org/ |
27 | and http://www.ecma-international.org/publications/files/ECMA-ST/ECMA-404.pdf |
28 | and https://tools.ietf.org/html/rfc7159 |
29 | |
30 | Supports creating a DOM-like tree of json::value *, and then dumping |
31 | json::value * to text. */ |
32 | |
33 | /* TODO: `libcpp/mkdeps.cc` wants JSON writing support for p1689r5 output; |
34 | extract this code and move to libiberty. */ |
35 | |
36 | namespace json |
37 | { |
38 | |
39 | /* Forward decls of json::value and its subclasses (using indentation |
40 | to denote inheritance. */ |
41 | |
42 | class value; |
43 | class object; |
44 | class array; |
45 | class float_number; |
46 | class integer_number; |
47 | class string; |
48 | class literal; |
49 | |
50 | /* An enum for discriminating the subclasses of json::value. */ |
51 | |
52 | enum kind |
53 | { |
54 | /* class json::object. */ |
55 | JSON_OBJECT, |
56 | |
57 | /* class json::array. */ |
58 | JSON_ARRAY, |
59 | |
60 | /* class json::integer_number. */ |
61 | JSON_INTEGER, |
62 | |
63 | /* class json::float_number. */ |
64 | JSON_FLOAT, |
65 | |
66 | /* class json::string. */ |
67 | JSON_STRING, |
68 | |
69 | /* class json::literal uses these three values to identify the |
70 | particular literal. */ |
71 | JSON_TRUE, |
72 | JSON_FALSE, |
73 | JSON_NULL |
74 | }; |
75 | |
76 | /* Base class of JSON value. */ |
77 | |
78 | class value |
79 | { |
80 | public: |
81 | virtual ~value () {} |
82 | virtual enum kind get_kind () const = 0; |
83 | virtual void print (pretty_printer *pp, bool formatted) const = 0; |
84 | |
85 | void dump (FILE *, bool formatted) const; |
86 | }; |
87 | |
88 | /* Subclass of value for objects: a collection of key/value pairs |
89 | preserving the ordering in which keys were inserted. |
90 | |
91 | Preserving the order eliminates non-determinism in the output, |
92 | making it easier for the user to compare repeated invocations. */ |
93 | |
94 | class object : public value |
95 | { |
96 | public: |
97 | ~object (); |
98 | |
99 | enum kind get_kind () const final override { return JSON_OBJECT; } |
100 | void print (pretty_printer *pp, bool formatted) const final override; |
101 | |
102 | void set (const char *key, value *v); |
103 | value *get (const char *key) const; |
104 | |
105 | void set_string (const char *key, const char *utf8_value); |
106 | void set_integer (const char *key, long v); |
107 | void set_float (const char *key, double v); |
108 | |
109 | /* Set to literal true/false. */ |
110 | void set_bool (const char *key, bool v); |
111 | |
112 | private: |
113 | typedef hash_map <char *, value *, |
114 | simple_hashmap_traits<nofree_string_hash, value *> > map_t; |
115 | map_t m_map; |
116 | |
117 | /* Keep track of order in which keys were inserted. */ |
118 | auto_vec <const char *> m_keys; |
119 | }; |
120 | |
121 | /* Subclass of value for arrays. */ |
122 | |
123 | class array : public value |
124 | { |
125 | public: |
126 | ~array (); |
127 | |
128 | enum kind get_kind () const final override { return JSON_ARRAY; } |
129 | void print (pretty_printer *pp, bool formatted) const final override; |
130 | |
131 | void append (value *v); |
132 | |
133 | private: |
134 | auto_vec<value *> m_elements; |
135 | }; |
136 | |
137 | /* Subclass of value for floating-point numbers. */ |
138 | |
139 | class float_number : public value |
140 | { |
141 | public: |
142 | float_number (double value) : m_value (value) {} |
143 | |
144 | enum kind get_kind () const final override { return JSON_FLOAT; } |
145 | void print (pretty_printer *pp, bool formatted) const final override; |
146 | |
147 | double get () const { return m_value; } |
148 | |
149 | private: |
150 | double m_value; |
151 | }; |
152 | |
153 | /* Subclass of value for integer-valued numbers. */ |
154 | |
155 | class integer_number : public value |
156 | { |
157 | public: |
158 | integer_number (long value) : m_value (value) {} |
159 | |
160 | enum kind get_kind () const final override { return JSON_INTEGER; } |
161 | void print (pretty_printer *pp, bool formatted) const final override; |
162 | |
163 | long get () const { return m_value; } |
164 | |
165 | private: |
166 | long m_value; |
167 | }; |
168 | |
169 | |
170 | /* Subclass of value for strings. */ |
171 | |
172 | class string : public value |
173 | { |
174 | public: |
175 | explicit string (const char *utf8); |
176 | string (const char *utf8, size_t len); |
177 | ~string () { free (ptr: m_utf8); } |
178 | |
179 | enum kind get_kind () const final override { return JSON_STRING; } |
180 | void print (pretty_printer *pp, bool formatted) const final override; |
181 | |
182 | const char *get_string () const { return m_utf8; } |
183 | size_t get_length () const { return m_len; } |
184 | |
185 | private: |
186 | char *m_utf8; |
187 | size_t m_len; |
188 | }; |
189 | |
190 | /* Subclass of value for the three JSON literals "true", "false", |
191 | and "null". */ |
192 | |
193 | class literal : public value |
194 | { |
195 | public: |
196 | literal (enum kind kind) : m_kind (kind) {} |
197 | |
198 | /* Construct literal for a boolean value. */ |
199 | literal (bool value): m_kind (value ? JSON_TRUE : JSON_FALSE) {} |
200 | |
201 | enum kind get_kind () const final override { return m_kind; } |
202 | void print (pretty_printer *pp, bool formatted) const final override; |
203 | |
204 | private: |
205 | enum kind m_kind; |
206 | }; |
207 | |
208 | } // namespace json |
209 | |
210 | #endif /* GCC_JSON_H */ |
211 | |