1 /*
2 * Copyright (C) 2015, The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "generate_cpp.h"
18
19 #include <cctype>
20 #include <cstring>
21 #include <memory>
22 #include <random>
23 #include <set>
24 #include <string>
25
26 #include <android-base/stringprintf.h>
27
28 #include "aidl_language.h"
29 #include "ast_cpp.h"
30 #include "code_writer.h"
31 #include "logging.h"
32 #include "os.h"
33
34 using android::base::StringPrintf;
35 using std::string;
36 using std::unique_ptr;
37 using std::vector;
38 using std::set;
39
40 namespace android {
41 namespace aidl {
42 namespace cpp {
43 namespace internals {
44 namespace {
45
46 const char kAndroidStatusVarName[] = "_aidl_ret_status";
47 const char kCodeVarName[] = "_aidl_code";
48 const char kFlagsVarName[] = "_aidl_flags";
49 const char kDataVarName[] = "_aidl_data";
50 const char kErrorLabel[] = "_aidl_error";
51 const char kImplVarName[] = "_aidl_impl";
52 const char kReplyVarName[] = "_aidl_reply";
53 const char kReturnVarName[] = "_aidl_return";
54 const char kStatusVarName[] = "_aidl_status";
55 const char kAndroidParcelLiteral[] = "::android::Parcel";
56 const char kAndroidStatusLiteral[] = "::android::status_t";
57 const char kAndroidStatusOk[] = "::android::OK";
58 const char kBinderStatusLiteral[] = "::android::binder::Status";
59 const char kIBinderHeader[] = "binder/IBinder.h";
60 const char kIInterfaceHeader[] = "binder/IInterface.h";
61 const char kParcelHeader[] = "binder/Parcel.h";
62 const char kStatusHeader[] = "binder/Status.h";
63 const char kString16Header[] = "utils/String16.h";
64 const char kStrongPointerHeader[] = "utils/StrongPointer.h";
65
BreakOnStatusNotOk()66 unique_ptr<AstNode> BreakOnStatusNotOk() {
67 IfStatement* ret = new IfStatement(new Comparison(
68 new LiteralExpression(kAndroidStatusVarName), "!=",
69 new LiteralExpression(kAndroidStatusOk)));
70 ret->OnTrue()->AddLiteral("break");
71 return unique_ptr<AstNode>(ret);
72 }
73
GotoErrorOnBadStatus()74 unique_ptr<AstNode> GotoErrorOnBadStatus() {
75 IfStatement* ret = new IfStatement(new Comparison(
76 new LiteralExpression(kAndroidStatusVarName), "!=",
77 new LiteralExpression(kAndroidStatusOk)));
78 ret->OnTrue()->AddLiteral(StringPrintf("goto %s", kErrorLabel));
79 return unique_ptr<AstNode>(ret);
80 }
81
82
ReturnOnStatusNotOk()83 unique_ptr<AstNode> ReturnOnStatusNotOk() {
84 IfStatement* ret = new IfStatement(new Comparison(
85 new LiteralExpression(kAndroidStatusVarName), "!=",
86 new LiteralExpression(kAndroidStatusOk)));
87 ret->OnTrue()->AddLiteral(StringPrintf("return %s", kAndroidStatusVarName));
88 return unique_ptr<AstNode>(ret);
89 }
90
UpperCase(const std::string & s)91 string UpperCase(const std::string& s) {
92 string result = s;
93 for (char& c : result)
94 c = toupper(c);
95 return result;
96 }
97
BuildVarName(const AidlArgument & a)98 string BuildVarName(const AidlArgument& a) {
99 string prefix = "out_";
100 if (a.GetDirection() & AidlArgument::IN_DIR) {
101 prefix = "in_";
102 }
103 return prefix + a.GetName();
104 }
105
BuildArgList(const TypeNamespace & types,const AidlMethod & method,bool for_declaration)106 ArgList BuildArgList(const TypeNamespace& types,
107 const AidlMethod& method,
108 bool for_declaration) {
109 // Build up the argument list for the server method call.
110 vector<string> method_arguments;
111 for (const unique_ptr<AidlArgument>& a : method.GetArguments()) {
112 string literal;
113 if (for_declaration) {
114 // Method declarations need types, pointers to out params, and variable
115 // names that match the .aidl specification.
116 const Type* type = a->GetType().GetLanguageType<Type>();
117
118 literal = type->CppType();
119
120 if (a->IsOut()) {
121 literal = literal + "*";
122 } else {
123 // We pass in parameters that are not primitives by const reference.
124 // Arrays of primitives are not primitives.
125 if (!type->IsCppPrimitive() || a->GetType().IsArray()) {
126 literal = "const " + literal + "&";
127 }
128 }
129
130 literal += " " + a->GetName();
131 } else {
132 if (a->IsOut()) { literal = "&"; }
133 literal += BuildVarName(*a);
134 }
135 method_arguments.push_back(literal);
136 }
137
138 const Type* return_type = method.GetType().GetLanguageType<Type>();
139
140 if (return_type != types.VoidType()) {
141 string literal;
142 if (for_declaration) {
143 literal = StringPrintf(
144 "%s* %s", return_type->CppType().c_str(),
145 kReturnVarName);
146 } else {
147 literal = string{"&"} + kReturnVarName;
148 }
149 method_arguments.push_back(literal);
150 }
151
152 return ArgList(method_arguments);
153 }
154
BuildMethodDecl(const AidlMethod & method,const TypeNamespace & types,bool for_interface)155 unique_ptr<Declaration> BuildMethodDecl(const AidlMethod& method,
156 const TypeNamespace& types,
157 bool for_interface) {
158 uint32_t modifiers = 0;
159 if (for_interface) {
160 modifiers |= MethodDecl::IS_VIRTUAL;
161 modifiers |= MethodDecl::IS_PURE_VIRTUAL;
162 } else {
163 modifiers |= MethodDecl::IS_OVERRIDE;
164 }
165
166 return unique_ptr<Declaration>{
167 new MethodDecl{kBinderStatusLiteral,
168 method.GetName(),
169 BuildArgList(types, method, true /* for method decl */),
170 modifiers}};
171 }
172
NestInNamespaces(vector<unique_ptr<Declaration>> decls,const vector<string> & package)173 unique_ptr<CppNamespace> NestInNamespaces(
174 vector<unique_ptr<Declaration>> decls,
175 const vector<string>& package) {
176 if (package.empty()) {
177 // We should also be checking this before we get this far, but do it again
178 // for the sake of unit tests and meaningful errors.
179 LOG(FATAL) << "C++ generation requires a package declaration "
180 "for namespacing";
181 }
182 auto it = package.crbegin(); // Iterate over the namespaces inner to outer
183 unique_ptr<CppNamespace> inner{new CppNamespace{*it, std::move(decls)}};
184 ++it;
185 for (; it != package.crend(); ++it) {
186 inner.reset(new CppNamespace{*it, std::move(inner)});
187 }
188 return inner;
189 }
190
NestInNamespaces(unique_ptr<Declaration> decl,const vector<string> & package)191 unique_ptr<CppNamespace> NestInNamespaces(unique_ptr<Declaration> decl,
192 const vector<string>& package) {
193 vector<unique_ptr<Declaration>> decls;
194 decls.push_back(std::move(decl));
195 return NestInNamespaces(std::move(decls), package);
196 }
197
DeclareLocalVariable(const TypeNamespace & types,const AidlArgument & a,StatementBlock * b)198 bool DeclareLocalVariable(const TypeNamespace& types, const AidlArgument& a,
199 StatementBlock* b) {
200 const Type* cpp_type = a.GetType().GetLanguageType<Type>();
201 if (!cpp_type) { return false; }
202
203 string type = cpp_type->CppType();
204
205 b->AddLiteral(type + " " + BuildVarName(a));
206 return true;
207 }
208
ClassName(const AidlInterface & interface,ClassNames type)209 string ClassName(const AidlInterface& interface, ClassNames type) {
210 string c_name = interface.GetName();
211
212 if (c_name.length() >= 2 && c_name[0] == 'I' && isupper(c_name[1]))
213 c_name = c_name.substr(1);
214
215 switch (type) {
216 case ClassNames::CLIENT:
217 c_name = "Bp" + c_name;
218 break;
219 case ClassNames::SERVER:
220 c_name = "Bn" + c_name;
221 break;
222 case ClassNames::INTERFACE:
223 c_name = "I" + c_name;
224 break;
225 case ClassNames::BASE:
226 break;
227 }
228 return c_name;
229 }
230
BuildHeaderGuard(const AidlInterface & interface,ClassNames header_type)231 string BuildHeaderGuard(const AidlInterface& interface,
232 ClassNames header_type) {
233 string class_name = ClassName(interface, header_type);
234 for (size_t i = 1; i < class_name.size(); ++i) {
235 if (isupper(class_name[i])) {
236 class_name.insert(i, "_");
237 ++i;
238 }
239 }
240 string ret = StringPrintf("AIDL_GENERATED_%s_%s_H_",
241 interface.GetPackage().c_str(),
242 class_name.c_str());
243 for (char& c : ret) {
244 if (c == '.') {
245 c = '_';
246 }
247 c = toupper(c);
248 }
249 return ret;
250 }
251
DefineClientTransaction(const TypeNamespace & types,const AidlInterface & interface,const AidlMethod & method)252 unique_ptr<Declaration> DefineClientTransaction(const TypeNamespace& types,
253 const AidlInterface& interface,
254 const AidlMethod& method) {
255 const string i_name = ClassName(interface, ClassNames::INTERFACE);
256 const string bp_name = ClassName(interface, ClassNames::CLIENT);
257 unique_ptr<MethodImpl> ret{new MethodImpl{
258 kBinderStatusLiteral, bp_name, method.GetName(),
259 ArgList{BuildArgList(types, method, true /* for method decl */)}}};
260 StatementBlock* b = ret->GetStatementBlock();
261
262 // Declare parcels to hold our query and the response.
263 b->AddLiteral(StringPrintf("%s %s", kAndroidParcelLiteral, kDataVarName));
264 // Even if we're oneway, the transact method still takes a parcel.
265 b->AddLiteral(StringPrintf("%s %s", kAndroidParcelLiteral, kReplyVarName));
266
267 // Declare the status_t variable we need for error handling.
268 b->AddLiteral(StringPrintf("%s %s = %s", kAndroidStatusLiteral,
269 kAndroidStatusVarName,
270 kAndroidStatusOk));
271 // We unconditionally return a Status object.
272 b->AddLiteral(StringPrintf("%s %s", kBinderStatusLiteral, kStatusVarName));
273
274 // Add the name of the interface we're hoping to call.
275 b->AddStatement(new Assignment(
276 kAndroidStatusVarName,
277 new MethodCall(StringPrintf("%s.writeInterfaceToken",
278 kDataVarName),
279 "getInterfaceDescriptor()")));
280 b->AddStatement(GotoErrorOnBadStatus());
281
282 for (const auto& a: method.GetArguments()) {
283 const Type* type = a->GetType().GetLanguageType<Type>();
284 string var_name = ((a->IsOut()) ? "*" : "") + a->GetName();
285 var_name = type->WriteCast(var_name);
286
287 if (a->IsIn()) {
288 // Serialization looks roughly like:
289 // _aidl_ret_status = _aidl_data.WriteInt32(in_param_name);
290 // if (_aidl_ret_status != ::android::OK) { goto error; }
291 const string& method = type->WriteToParcelMethod();
292 b->AddStatement(new Assignment(
293 kAndroidStatusVarName,
294 new MethodCall(StringPrintf("%s.%s", kDataVarName, method.c_str()),
295 ArgList(var_name))));
296 b->AddStatement(GotoErrorOnBadStatus());
297 } else if (a->IsOut() && a->GetType().IsArray()) {
298 // Special case, the length of the out array is written into the parcel.
299 // _aidl_ret_status = _aidl_data.writeVectorSize(&out_param_name);
300 // if (_aidl_ret_status != ::android::OK) { goto error; }
301 b->AddStatement(new Assignment(
302 kAndroidStatusVarName,
303 new MethodCall(StringPrintf("%s.writeVectorSize", kDataVarName),
304 ArgList(var_name))));
305 b->AddStatement(GotoErrorOnBadStatus());
306 }
307 }
308
309 // Invoke the transaction on the remote binder and confirm status.
310 string transaction_code = StringPrintf(
311 "%s::%s", i_name.c_str(), UpperCase(method.GetName()).c_str());
312
313 vector<string> args = {transaction_code, kDataVarName,
314 StringPrintf("&%s", kReplyVarName)};
315
316 if (interface.IsOneway() || method.IsOneway()) {
317 args.push_back("::android::IBinder::FLAG_ONEWAY");
318 }
319
320 b->AddStatement(new Assignment(
321 kAndroidStatusVarName,
322 new MethodCall("remote()->transact",
323 ArgList(args))));
324 b->AddStatement(GotoErrorOnBadStatus());
325
326 if (!interface.IsOneway() && !method.IsOneway()) {
327 // Strip off the exception header and fail if we see a remote exception.
328 // _aidl_ret_status = _aidl_status.readFromParcel(_aidl_reply);
329 // if (_aidl_ret_status != ::android::OK) { goto error; }
330 // if (!_aidl_status.isOk()) { return _aidl_ret_status; }
331 b->AddStatement(new Assignment(
332 kAndroidStatusVarName,
333 StringPrintf("%s.readFromParcel(%s)", kStatusVarName, kReplyVarName)));
334 b->AddStatement(GotoErrorOnBadStatus());
335 IfStatement* exception_check = new IfStatement(
336 new LiteralExpression(StringPrintf("!%s.isOk()", kStatusVarName)));
337 b->AddStatement(exception_check);
338 exception_check->OnTrue()->AddLiteral(
339 StringPrintf("return %s", kStatusVarName));
340 }
341
342 // Type checking should guarantee that nothing below emits code until "return
343 // status" if we are a oneway method, so no more fear of accessing reply.
344
345 // If the method is expected to return something, read it first by convention.
346 const Type* return_type = method.GetType().GetLanguageType<Type>();
347 if (return_type != types.VoidType()) {
348 const string& method_call = return_type->ReadFromParcelMethod();
349 b->AddStatement(new Assignment(
350 kAndroidStatusVarName,
351 new MethodCall(StringPrintf("%s.%s", kReplyVarName,
352 method_call.c_str()),
353 ArgList(kReturnVarName))));
354 b->AddStatement(GotoErrorOnBadStatus());
355 }
356
357 for (const AidlArgument* a : method.GetOutArguments()) {
358 // Deserialization looks roughly like:
359 // _aidl_ret_status = _aidl_reply.ReadInt32(out_param_name);
360 // if (_aidl_status != ::android::OK) { goto _aidl_error; }
361 string method =
362 a->GetType().GetLanguageType<Type>()->ReadFromParcelMethod();
363
364 b->AddStatement(new Assignment(
365 kAndroidStatusVarName,
366 new MethodCall(StringPrintf("%s.%s", kReplyVarName,
367 method.c_str()),
368 ArgList(a->GetName()))));
369 b->AddStatement(GotoErrorOnBadStatus());
370 }
371
372 // If we've gotten to here, one of two things is true:
373 // 1) We've read some bad status_t
374 // 2) We've only read status_t == OK and there was no exception in the
375 // response.
376 // In both cases, we're free to set Status from the status_t and return.
377 b->AddLiteral(StringPrintf("%s:\n", kErrorLabel), false /* no semicolon */);
378 b->AddLiteral(
379 StringPrintf("%s.setFromStatusT(%s)", kStatusVarName,
380 kAndroidStatusVarName));
381 b->AddLiteral(StringPrintf("return %s", kStatusVarName));
382
383 return unique_ptr<Declaration>(ret.release());
384 }
385
386 } // namespace
387
BuildClientSource(const TypeNamespace & types,const AidlInterface & interface)388 unique_ptr<Document> BuildClientSource(const TypeNamespace& types,
389 const AidlInterface& interface) {
390 vector<string> include_list = {
391 HeaderFile(interface, ClassNames::CLIENT, false),
392 kParcelHeader
393 };
394 vector<unique_ptr<Declaration>> file_decls;
395
396 // The constructor just passes the IBinder instance up to the super
397 // class.
398 const string i_name = ClassName(interface, ClassNames::INTERFACE);
399 file_decls.push_back(unique_ptr<Declaration>{new ConstructorImpl{
400 ClassName(interface, ClassNames::CLIENT),
401 ArgList{StringPrintf("const ::android::sp<::android::IBinder>& %s",
402 kImplVarName)},
403 { "BpInterface<" + i_name + ">(" + kImplVarName + ")" }}});
404
405 // Clients define a method per transaction.
406 for (const auto& method : interface.GetMethods()) {
407 unique_ptr<Declaration> m = DefineClientTransaction(
408 types, interface, *method);
409 if (!m) { return nullptr; }
410 file_decls.push_back(std::move(m));
411 }
412 return unique_ptr<Document>{new CppSource{
413 include_list,
414 NestInNamespaces(std::move(file_decls), interface.GetSplitPackage())}};
415 }
416
417 namespace {
418
HandleServerTransaction(const TypeNamespace & types,const AidlMethod & method,StatementBlock * b)419 bool HandleServerTransaction(const TypeNamespace& types,
420 const AidlMethod& method,
421 StatementBlock* b) {
422 // Declare all the parameters now. In the common case, we expect no errors
423 // in serialization.
424 for (const unique_ptr<AidlArgument>& a : method.GetArguments()) {
425 if (!DeclareLocalVariable(types, *a, b)) { return false; }
426 }
427
428 // Declare a variable to hold the return value.
429 const Type* return_type = method.GetType().GetLanguageType<Type>();
430 if (return_type != types.VoidType()) {
431 b->AddLiteral(StringPrintf(
432 "%s %s", return_type->CppType().c_str(),
433 kReturnVarName));
434 }
435
436 // Check that the client is calling the correct interface.
437 IfStatement* interface_check = new IfStatement(
438 new MethodCall(StringPrintf("%s.checkInterface",
439 kDataVarName), "this"),
440 true /* invert the check */);
441 b->AddStatement(interface_check);
442 interface_check->OnTrue()->AddStatement(
443 new Assignment(kAndroidStatusVarName, "::android::BAD_TYPE"));
444 interface_check->OnTrue()->AddLiteral("break");
445
446 // Deserialize each "in" parameter to the transaction.
447 for (const auto& a: method.GetArguments()) {
448 // Deserialization looks roughly like:
449 // _aidl_ret_status = _aidl_data.ReadInt32(&in_param_name);
450 // if (_aidl_ret_status != ::android::OK) { break; }
451 const Type* type = a->GetType().GetLanguageType<Type>();
452 const string& readMethod = type->ReadFromParcelMethod();
453
454 if (a->IsIn()) {
455 b->AddStatement(new Assignment{
456 kAndroidStatusVarName,
457 new MethodCall{string(kDataVarName) + "." + readMethod,
458 "&" + BuildVarName(*a)}});
459 b->AddStatement(BreakOnStatusNotOk());
460 } else if (a->IsOut() && a->GetType().IsArray()) {
461 // Special case, the length of the out array is written into the parcel.
462 // _aidl_ret_status = _aidl_data.resizeOutVector(&out_param_name);
463 // if (_aidl_ret_status != ::android::OK) { break; }
464 b->AddStatement(new Assignment{
465 kAndroidStatusVarName,
466 new MethodCall{string(kDataVarName) + ".resizeOutVector",
467 "&" + BuildVarName(*a)}});
468 b->AddStatement(BreakOnStatusNotOk());
469 }
470 }
471
472 // Call the actual method. This is implemented by the subclass.
473 vector<unique_ptr<AstNode>> status_args;
474 status_args.emplace_back(new MethodCall(
475 method.GetName(),
476 BuildArgList(types, method, false /* not for method decl */)));
477 b->AddStatement(new Statement(new MethodCall(
478 StringPrintf("%s %s", kBinderStatusLiteral, kStatusVarName),
479 ArgList(std::move(status_args)))));
480
481 // Write exceptions during transaction handling to parcel.
482 if (!method.IsOneway()) {
483 b->AddStatement(new Assignment(
484 kAndroidStatusVarName,
485 StringPrintf("%s.writeToParcel(%s)", kStatusVarName, kReplyVarName)));
486 b->AddStatement(BreakOnStatusNotOk());
487 IfStatement* exception_check = new IfStatement(
488 new LiteralExpression(StringPrintf("!%s.isOk()", kStatusVarName)));
489 b->AddStatement(exception_check);
490 exception_check->OnTrue()->AddLiteral("break");
491 }
492
493 // If we have a return value, write it first.
494 if (return_type != types.VoidType()) {
495 string writeMethod =
496 string(kReplyVarName) + "->" +
497 return_type->WriteToParcelMethod();
498 b->AddStatement(new Assignment{
499 kAndroidStatusVarName, new MethodCall{writeMethod,
500 ArgList{return_type->WriteCast(kReturnVarName)}}});
501 b->AddStatement(BreakOnStatusNotOk());
502 }
503
504 // Write each out parameter to the reply parcel.
505 for (const AidlArgument* a : method.GetOutArguments()) {
506 // Serialization looks roughly like:
507 // _aidl_ret_status = data.WriteInt32(out_param_name);
508 // if (_aidl_ret_status != ::android::OK) { break; }
509 const Type* type = a->GetType().GetLanguageType<Type>();
510 const string& writeMethod = type->WriteToParcelMethod();
511
512 b->AddStatement(new Assignment{
513 kAndroidStatusVarName,
514 new MethodCall{string(kReplyVarName) + "->" + writeMethod,
515 type->WriteCast(BuildVarName(*a))}});
516 b->AddStatement(BreakOnStatusNotOk());
517 }
518
519 return true;
520 }
521
522 } // namespace
523
BuildServerSource(const TypeNamespace & types,const AidlInterface & interface)524 unique_ptr<Document> BuildServerSource(const TypeNamespace& types,
525 const AidlInterface& interface) {
526 const string bn_name = ClassName(interface, ClassNames::SERVER);
527 vector<string> include_list{
528 HeaderFile(interface, ClassNames::SERVER, false),
529 kParcelHeader
530 };
531 unique_ptr<MethodImpl> on_transact{new MethodImpl{
532 kAndroidStatusLiteral, bn_name, "onTransact",
533 ArgList{{StringPrintf("uint32_t %s", kCodeVarName),
534 StringPrintf("const %s& %s", kAndroidParcelLiteral,
535 kDataVarName),
536 StringPrintf("%s* %s", kAndroidParcelLiteral, kReplyVarName),
537 StringPrintf("uint32_t %s", kFlagsVarName)}}
538 }};
539
540 // Declare the status_t variable
541 on_transact->GetStatementBlock()->AddLiteral(
542 StringPrintf("%s %s = %s", kAndroidStatusLiteral, kAndroidStatusVarName,
543 kAndroidStatusOk));
544
545 // Add the all important switch statement, but retain a pointer to it.
546 SwitchStatement* s = new SwitchStatement{kCodeVarName};
547 on_transact->GetStatementBlock()->AddStatement(s);
548
549 // The switch statement has a case statement for each transaction code.
550 for (const auto& method : interface.GetMethods()) {
551 StatementBlock* b = s->AddCase("Call::" + UpperCase(method->GetName()));
552 if (!b) { return nullptr; }
553
554 if (!HandleServerTransaction(types, *method, b)) { return nullptr; }
555 }
556
557 // The switch statement has a default case which defers to the super class.
558 // The superclass handles a few pre-defined transactions.
559 StatementBlock* b = s->AddCase("");
560 b->AddLiteral(StringPrintf(
561 "%s = ::android::BBinder::onTransact(%s, %s, "
562 "%s, %s)", kAndroidStatusVarName, kCodeVarName,
563 kDataVarName, kReplyVarName, kFlagsVarName));
564
565 // If we saw a null reference, we can map that to an appropriate exception.
566 IfStatement* null_check = new IfStatement(
567 new LiteralExpression(string(kAndroidStatusVarName) +
568 " == ::android::UNEXPECTED_NULL"));
569 on_transact->GetStatementBlock()->AddStatement(null_check);
570 null_check->OnTrue()->AddStatement(new Assignment(
571 kAndroidStatusVarName,
572 StringPrintf("%s::fromExceptionCode(%s::EX_NULL_POINTER)"
573 ".writeToParcel(%s)",
574 kBinderStatusLiteral, kBinderStatusLiteral,
575 kReplyVarName)));
576
577 // Finally, the server's onTransact method just returns a status code.
578 on_transact->GetStatementBlock()->AddLiteral(
579 StringPrintf("return %s", kAndroidStatusVarName));
580
581 return unique_ptr<Document>{new CppSource{
582 include_list,
583 NestInNamespaces(std::move(on_transact), interface.GetSplitPackage())}};
584 }
585
BuildInterfaceSource(const TypeNamespace &,const AidlInterface & interface)586 unique_ptr<Document> BuildInterfaceSource(const TypeNamespace& /* types */,
587 const AidlInterface& interface) {
588 vector<string> include_list{
589 HeaderFile(interface, ClassNames::INTERFACE, false),
590 HeaderFile(interface, ClassNames::CLIENT, false),
591 };
592
593 string fq_name = ClassName(interface, ClassNames::INTERFACE);
594 if (!interface.GetPackage().empty()) {
595 fq_name = interface.GetPackage() + "." + fq_name;
596 }
597
598 vector<unique_ptr<Declaration>> decls;
599
600 unique_ptr<MacroDecl> meta_if{new MacroDecl{
601 "IMPLEMENT_META_INTERFACE",
602 ArgList{vector<string>{ClassName(interface, ClassNames::BASE),
603 '"' + fq_name + '"'}}}};
604 decls.push_back(std::move(meta_if));
605
606 for (const auto& constant: interface.GetStringConstants()) {
607 unique_ptr<MethodImpl> getter(new MethodImpl(
608 "const ::android::String16&",
609 ClassName(interface, ClassNames::INTERFACE),
610 constant->GetName(),
611 {}));
612 getter->GetStatementBlock()->AddLiteral(
613 StringPrintf("static const ::android::String16 value(%s)",
614 constant->GetValue().c_str()));
615 getter->GetStatementBlock()->AddLiteral("return value");
616 decls.push_back(std::move(getter));
617 }
618
619 return unique_ptr<Document>{new CppSource{
620 include_list,
621 NestInNamespaces(std::move(decls), interface.GetSplitPackage())}};
622 }
623
BuildClientHeader(const TypeNamespace & types,const AidlInterface & interface)624 unique_ptr<Document> BuildClientHeader(const TypeNamespace& types,
625 const AidlInterface& interface) {
626 const string i_name = ClassName(interface, ClassNames::INTERFACE);
627 const string bp_name = ClassName(interface, ClassNames::CLIENT);
628
629 unique_ptr<ConstructorDecl> constructor{new ConstructorDecl{
630 bp_name,
631 ArgList{StringPrintf("const ::android::sp<::android::IBinder>& %s",
632 kImplVarName)},
633 ConstructorDecl::IS_EXPLICIT
634 }};
635 unique_ptr<ConstructorDecl> destructor{new ConstructorDecl{
636 "~" + bp_name,
637 ArgList{},
638 ConstructorDecl::IS_VIRTUAL | ConstructorDecl::IS_DEFAULT}};
639
640 vector<unique_ptr<Declaration>> publics;
641 publics.push_back(std::move(constructor));
642 publics.push_back(std::move(destructor));
643
644 for (const auto& method: interface.GetMethods()) {
645 publics.push_back(BuildMethodDecl(*method, types, false));
646 }
647
648 unique_ptr<ClassDecl> bp_class{
649 new ClassDecl{bp_name,
650 "::android::BpInterface<" + i_name + ">",
651 std::move(publics),
652 {}
653 }};
654
655 return unique_ptr<Document>{new CppHeader{
656 BuildHeaderGuard(interface, ClassNames::CLIENT),
657 {kIBinderHeader,
658 kIInterfaceHeader,
659 "utils/Errors.h",
660 HeaderFile(interface, ClassNames::INTERFACE, false)},
661 NestInNamespaces(std::move(bp_class), interface.GetSplitPackage())}};
662 }
663
BuildServerHeader(const TypeNamespace &,const AidlInterface & interface)664 unique_ptr<Document> BuildServerHeader(const TypeNamespace& /* types */,
665 const AidlInterface& interface) {
666 const string i_name = ClassName(interface, ClassNames::INTERFACE);
667 const string bn_name = ClassName(interface, ClassNames::SERVER);
668
669 unique_ptr<Declaration> on_transact{new MethodDecl{
670 kAndroidStatusLiteral, "onTransact",
671 ArgList{{StringPrintf("uint32_t %s", kCodeVarName),
672 StringPrintf("const %s& %s", kAndroidParcelLiteral,
673 kDataVarName),
674 StringPrintf("%s* %s", kAndroidParcelLiteral, kReplyVarName),
675 StringPrintf("uint32_t %s = 0", kFlagsVarName)}},
676 MethodDecl::IS_OVERRIDE
677 }};
678
679 std::vector<unique_ptr<Declaration>> publics;
680 publics.push_back(std::move(on_transact));
681
682 unique_ptr<ClassDecl> bn_class{
683 new ClassDecl{bn_name,
684 "::android::BnInterface<" + i_name + ">",
685 std::move(publics),
686 {}
687 }};
688
689 return unique_ptr<Document>{new CppHeader{
690 BuildHeaderGuard(interface, ClassNames::SERVER),
691 {"binder/IInterface.h",
692 HeaderFile(interface, ClassNames::INTERFACE, false)},
693 NestInNamespaces(std::move(bn_class), interface.GetSplitPackage())}};
694 }
695
BuildInterfaceHeader(const TypeNamespace & types,const AidlInterface & interface)696 unique_ptr<Document> BuildInterfaceHeader(const TypeNamespace& types,
697 const AidlInterface& interface) {
698 set<string> includes = { kIBinderHeader, kIInterfaceHeader,
699 kStatusHeader, kStrongPointerHeader };
700
701 for (const auto& method : interface.GetMethods()) {
702 for (const auto& argument : method->GetArguments()) {
703 const Type* type = argument->GetType().GetLanguageType<Type>();
704 type->GetHeaders(&includes);
705 }
706
707 const Type* return_type = method->GetType().GetLanguageType<Type>();
708 return_type->GetHeaders(&includes);
709 }
710
711 unique_ptr<ClassDecl> if_class{
712 new ClassDecl{ClassName(interface, ClassNames::INTERFACE),
713 "::android::IInterface"}};
714 if_class->AddPublic(unique_ptr<Declaration>{new MacroDecl{
715 "DECLARE_META_INTERFACE",
716 ArgList{vector<string>{ClassName(interface, ClassNames::BASE)}}}});
717
718 unique_ptr<Enum> constant_enum{new Enum{"", "int32_t"}};
719 for (const auto& constant : interface.GetIntConstants()) {
720 constant_enum->AddValue(
721 constant->GetName(), std::to_string(constant->GetValue()));
722 }
723 if (constant_enum->HasValues()) {
724 if_class->AddPublic(std::move(constant_enum));
725 }
726
727 if (!interface.GetStringConstants().empty()) {
728 includes.insert(kString16Header);
729 }
730 for (const auto& constant : interface.GetStringConstants()) {
731 unique_ptr<MethodDecl> getter(new MethodDecl(
732 "const ::android::String16&", constant->GetName(),
733 {}, MethodDecl::IS_STATIC));
734 if_class->AddPublic(std::move(getter));
735 }
736
737 if (!interface.GetMethods().empty()) {
738 unique_ptr<Enum> call_enum{new Enum{"Call"}};
739 for (const auto& method : interface.GetMethods()) {
740 // Each method gets an enum entry and pure virtual declaration.
741 if_class->AddPublic(BuildMethodDecl(*method, types, true));
742 call_enum->AddValue(
743 UpperCase(method->GetName()),
744 StringPrintf("::android::IBinder::FIRST_CALL_TRANSACTION + %d",
745 method->GetId()));
746 }
747 if_class->AddPublic(std::move(call_enum));
748 }
749
750 return unique_ptr<Document>{new CppHeader{
751 BuildHeaderGuard(interface, ClassNames::INTERFACE),
752 vector<string>(includes.begin(), includes.end()),
753 NestInNamespaces(std::move(if_class), interface.GetSplitPackage())}};
754 }
755
WriteHeader(const CppOptions & options,const TypeNamespace & types,const AidlInterface & interface,const IoDelegate & io_delegate,ClassNames header_type)756 bool WriteHeader(const CppOptions& options,
757 const TypeNamespace& types,
758 const AidlInterface& interface,
759 const IoDelegate& io_delegate,
760 ClassNames header_type) {
761 unique_ptr<Document> header;
762 switch (header_type) {
763 case ClassNames::INTERFACE:
764 header = BuildInterfaceHeader(types, interface);
765 break;
766 case ClassNames::CLIENT:
767 header = BuildClientHeader(types, interface);
768 break;
769 case ClassNames::SERVER:
770 header = BuildServerHeader(types, interface);
771 break;
772 default:
773 LOG(FATAL) << "aidl internal error";
774 }
775 if (!header) {
776 LOG(ERROR) << "aidl internal error: Failed to generate header.";
777 return false;
778 }
779
780 const string header_path = options.OutputHeaderDir() + OS_PATH_SEPARATOR +
781 HeaderFile(interface, header_type);
782 unique_ptr<CodeWriter> code_writer(io_delegate.GetCodeWriter(header_path));
783 header->Write(code_writer.get());
784
785 const bool success = code_writer->Close();
786 if (!success) {
787 io_delegate.RemovePath(header_path);
788 }
789
790 return success;
791 }
792
793 } // namespace internals
794
795 using namespace internals;
796
HeaderFile(const AidlInterface & interface,ClassNames class_type,bool use_os_sep)797 string HeaderFile(const AidlInterface& interface,
798 ClassNames class_type,
799 bool use_os_sep) {
800 string file_path = interface.GetPackage();
801 for (char& c: file_path) {
802 if (c == '.') {
803 c = (use_os_sep) ? OS_PATH_SEPARATOR : '/';
804 }
805 }
806 if (!file_path.empty()) {
807 file_path += (use_os_sep) ? OS_PATH_SEPARATOR : '/';
808 }
809 file_path += ClassName(interface, class_type);
810 file_path += ".h";
811
812 return file_path;
813 }
814
GenerateCpp(const CppOptions & options,const TypeNamespace & types,const AidlInterface & interface,const IoDelegate & io_delegate)815 bool GenerateCpp(const CppOptions& options,
816 const TypeNamespace& types,
817 const AidlInterface& interface,
818 const IoDelegate& io_delegate) {
819 auto interface_src = BuildInterfaceSource(types, interface);
820 auto client_src = BuildClientSource(types, interface);
821 auto server_src = BuildServerSource(types, interface);
822
823 if (!interface_src || !client_src || !server_src) {
824 return false;
825 }
826
827 if (!io_delegate.CreatedNestedDirs(options.OutputHeaderDir(),
828 interface.GetSplitPackage())) {
829 LOG(ERROR) << "Failed to create directory structure for headers.";
830 return false;
831 }
832
833 if (!WriteHeader(options, types, interface, io_delegate,
834 ClassNames::INTERFACE) ||
835 !WriteHeader(options, types, interface, io_delegate,
836 ClassNames::CLIENT) ||
837 !WriteHeader(options, types, interface, io_delegate,
838 ClassNames::SERVER)) {
839 return false;
840 }
841
842 unique_ptr<CodeWriter> writer = io_delegate.GetCodeWriter(
843 options.OutputCppFilePath());
844 interface_src->Write(writer.get());
845 client_src->Write(writer.get());
846 server_src->Write(writer.get());
847
848 const bool success = writer->Close();
849 if (!success) {
850 io_delegate.RemovePath(options.OutputCppFilePath());
851 }
852
853 return success;
854 }
855
856 } // namespace cpp
857 } // namespace aidl
858 } // namespace android
859