1 // Protocol Buffers - Google's data interchange format
2 // Copyright 2023 Google LLC. All rights reserved.
3 //
4 // Use of this source code is governed by a BSD-style
5 // license that can be found in the LICENSE file or at
6 // https://developers.google.com/open-source/licenses/bsd
7
8 #include <cstddef>
9 #include <string>
10
11 #include "google/protobuf/descriptor.upb.h"
12 #include "absl/strings/escaping.h"
13 #include "absl/strings/string_view.h"
14 #include "absl/strings/substitute.h"
15 #include "upb/mem/arena.hpp"
16 #include "upb/reflection/def.hpp"
17 #include "upb/util/def_to_proto.h"
18 #include "upb_generator/common.h"
19 #include "upb_generator/common/names.h"
20 #include "upb_generator/file_layout.h"
21 #include "upb_generator/minitable/names.h"
22 #include "upb_generator/plugin.h"
23 #include "upb_generator/reflection/names.h"
24
25 namespace upb {
26 namespace generator {
27 namespace {
28
29 struct Options {
30 std::string dllexport_decl;
31 };
32
DefInitSymbol(upb::FileDefPtr file)33 std::string DefInitSymbol(upb::FileDefPtr file) {
34 return ReflectionFileSymbol(file.name());
35 }
36
DefHeaderFilename(upb::FileDefPtr file)37 static std::string DefHeaderFilename(upb::FileDefPtr file) {
38 return StripExtension(file.name()) + ".upbdefs.h";
39 }
40
DefSourceFilename(upb::FileDefPtr file)41 static std::string DefSourceFilename(upb::FileDefPtr file) {
42 return StripExtension(file.name()) + ".upbdefs.c";
43 }
44
GenerateMessageDefAccessor(upb::MessageDefPtr d,Output & output)45 void GenerateMessageDefAccessor(upb::MessageDefPtr d, Output& output) {
46 output("UPB_INLINE const upb_MessageDef *$0(upb_DefPool *s) {\n",
47 ReflectionGetMessageSymbol(d.full_name()));
48 output(" _upb_DefPool_LoadDefInit(s, &$0);\n", DefInitSymbol(d.file()));
49 output(" return upb_DefPool_FindMessageByName(s, \"$0\");\n", d.full_name());
50 output("}\n");
51 output("\n");
52 }
53
WriteDefHeader(upb::FileDefPtr file,const Options & options,Output & output)54 void WriteDefHeader(upb::FileDefPtr file, const Options& options,
55 Output& output) {
56 output(FileWarning(file.name()));
57
58 output(
59 "#ifndef $0_UPBDEFS_H_\n"
60 "#define $0_UPBDEFS_H_\n\n"
61 "#include \"upb/reflection/def.h\"\n"
62 "#include \"upb/reflection/internal/def_pool.h\"\n"
63 "\n"
64 "#include \"upb/port/def.inc\" // Must be last.\n"
65 "#ifdef __cplusplus\n"
66 "extern \"C\" {\n"
67 "#endif\n\n",
68 IncludeGuard(file.name()));
69
70 output("extern$1 _upb_DefPool_Init $0;\n", DefInitSymbol(file),
71 PadPrefix(options.dllexport_decl));
72 output("\n");
73
74 for (auto msg : SortedMessages(file)) {
75 GenerateMessageDefAccessor(msg, output);
76 }
77
78 output(
79 "#ifdef __cplusplus\n"
80 "} /* extern \"C\" */\n"
81 "#endif\n"
82 "\n"
83 "#include \"upb/port/undef.inc\"\n"
84 "\n"
85 "#endif /* $0_UPBDEFS_H_ */\n",
86 IncludeGuard(file.name()));
87 }
88
WriteDefSource(upb::FileDefPtr file,const Options & options,Output & output)89 void WriteDefSource(upb::FileDefPtr file, const Options& options,
90 Output& output) {
91 output(FileWarning(file.name()));
92
93 output("#include \"upb/reflection/def.h\"\n");
94 output("#include \"$0\"\n", DefHeaderFilename(file));
95 output("#include \"$0\"\n", MiniTableHeaderFilename(file.name()));
96 output("\n");
97
98 for (int i = 0; i < file.dependency_count(); i++) {
99 output("extern$1 _upb_DefPool_Init $0;\n",
100 DefInitSymbol(file.dependency(i)),
101 PadPrefix(options.dllexport_decl));
102 }
103
104 upb::Arena arena;
105 google_protobuf_FileDescriptorProto* file_proto =
106 upb_FileDef_ToProto(file.ptr(), arena.ptr());
107 size_t serialized_size;
108 const char* serialized = google_protobuf_FileDescriptorProto_serialize(
109 file_proto, arena.ptr(), &serialized_size);
110 absl::string_view file_data(serialized, serialized_size);
111
112 output("static const char descriptor[$0] = {", serialized_size);
113
114 // C90 only guarantees that strings can be up to 509 characters, and some
115 // implementations have limits here (for example, MSVC only allows 64k:
116 // https://docs.microsoft.com/en-us/cpp/error-messages/compiler-errors-1/fatal-error-c1091.
117 // So we always emit an array instead of a string.
118 for (size_t i = 0; i < serialized_size;) {
119 for (size_t j = 0; j < 25 && i < serialized_size; ++i, ++j) {
120 output("'$0', ", absl::CEscape(file_data.substr(i, 1)));
121 }
122 output("\n");
123 }
124 output("};\n\n");
125
126 output("static _upb_DefPool_Init *deps[$0] = {\n",
127 file.dependency_count() + 1);
128 for (int i = 0; i < file.dependency_count(); i++) {
129 output(" &$0,\n", DefInitSymbol(file.dependency(i)));
130 }
131 output(" NULL\n");
132 output("};\n");
133 output("\n");
134
135 output("_upb_DefPool_Init $0 = {\n", DefInitSymbol(file));
136 output(" deps,\n");
137 output(" &$0,\n", MiniTableFileVarName(file.name()));
138 output(" \"$0\",\n", file.name());
139 output(" UPB_STRINGVIEW_INIT(descriptor, $0)\n", file_data.size());
140 output("};\n");
141 }
142
GenerateFile(upb::FileDefPtr file,const Options & options,Plugin * plugin)143 void GenerateFile(upb::FileDefPtr file, const Options& options,
144 Plugin* plugin) {
145 Output h_def_output;
146 WriteDefHeader(file, options, h_def_output);
147 plugin->AddOutputFile(DefHeaderFilename(file), h_def_output.output());
148
149 Output c_def_output;
150 WriteDefSource(file, options, c_def_output);
151 plugin->AddOutputFile(DefSourceFilename(file), c_def_output.output());
152 }
153
ParseOptions(Plugin * plugin,Options * options)154 bool ParseOptions(Plugin* plugin, Options* options) {
155 for (const auto& pair : ParseGeneratorParameter(plugin->parameter())) {
156 if (pair.first == "dllexport_decl") {
157 options->dllexport_decl = pair.second;
158 } else {
159 plugin->SetError(absl::Substitute("Unknown parameter: $0", pair.first));
160 return false;
161 }
162 }
163
164 return true;
165 }
166
167 } // namespace
168 } // namespace generator
169 } // namespace upb
170
main(int argc,char ** argv)171 int main(int argc, char** argv) {
172 upb::generator::Plugin plugin;
173 upb::generator::Options options;
174 if (!ParseOptions(&plugin, &options)) return 0;
175 plugin.GenerateFiles([&](upb::FileDefPtr file) {
176 upb::generator::GenerateFile(file, options, &plugin);
177 });
178 return 0;
179 }
180