1 //===-- Language.h ---------------------------------------------------*- C++
2 //-*-===//
3 //
4 //                     The LLVM Compiler Infrastructure
5 //
6 // This file is distributed under the University of Illinois Open Source
7 // License. See LICENSE.TXT for details.
8 //
9 //===----------------------------------------------------------------------===//
10 
11 #ifndef liblldb_Language_h_
12 #define liblldb_Language_h_
13 
14 #include <functional>
15 #include <memory>
16 #include <set>
17 #include <vector>
18 
19 #include "lldb/Core/Highlighter.h"
20 #include "lldb/Core/PluginInterface.h"
21 #include "lldb/DataFormatters/DumpValueObjectOptions.h"
22 #include "lldb/DataFormatters/FormatClasses.h"
23 #include "lldb/DataFormatters/StringPrinter.h"
24 #include "lldb/lldb-private.h"
25 #include "lldb/lldb-public.h"
26 
27 namespace lldb_private {
28 
29 class Language : public PluginInterface {
30 public:
31   class TypeScavenger {
32   public:
33     class Result {
34     public:
35       virtual bool IsValid() = 0;
36 
37       virtual bool DumpToStream(Stream &stream,
38                                 bool print_help_if_available) = 0;
39 
40       virtual ~Result() = default;
41     };
42 
43     typedef std::set<std::unique_ptr<Result>> ResultSet;
44 
45     virtual ~TypeScavenger() = default;
46 
47     size_t Find(ExecutionContextScope *exe_scope, const char *key,
48                 ResultSet &results, bool append = true);
49 
50   protected:
51     TypeScavenger() = default;
52 
53     virtual bool Find_Impl(ExecutionContextScope *exe_scope, const char *key,
54                            ResultSet &results) = 0;
55   };
56 
57   class ImageListTypeScavenger : public TypeScavenger {
58     class Result : public Language::TypeScavenger::Result {
59     public:
Result(CompilerType type)60       Result(CompilerType type)
61           : Language::TypeScavenger::Result(), m_compiler_type(type) {}
62 
IsValid()63       bool IsValid() override { return m_compiler_type.IsValid(); }
64 
DumpToStream(Stream & stream,bool print_help_if_available)65       bool DumpToStream(Stream &stream, bool print_help_if_available) override {
66         if (IsValid()) {
67           m_compiler_type.DumpTypeDescription(&stream);
68           stream.EOL();
69           return true;
70         }
71         return false;
72       }
73 
74       ~Result() override = default;
75 
76     private:
77       CompilerType m_compiler_type;
78     };
79 
80   protected:
81     ImageListTypeScavenger() = default;
82 
83     ~ImageListTypeScavenger() override = default;
84 
85     // is this type something we should accept? it's usually going to be a
86     // filter by language + maybe some sugar tweaking
87     // returning an empty type means rejecting this candidate entirely;
88     // any other result will be accepted as a valid match
89     virtual CompilerType AdjustForInclusion(CompilerType &candidate) = 0;
90 
91     bool Find_Impl(ExecutionContextScope *exe_scope, const char *key,
92                    ResultSet &results) override;
93   };
94 
95   template <typename... ScavengerTypes>
96   class EitherTypeScavenger : public TypeScavenger {
97   public:
EitherTypeScavenger()98     EitherTypeScavenger() : TypeScavenger(), m_scavengers() {
99       for (std::shared_ptr<TypeScavenger> scavenger : { std::shared_ptr<TypeScavenger>(new ScavengerTypes())... }) {
100         if (scavenger)
101           m_scavengers.push_back(scavenger);
102       }
103     }
104   protected:
Find_Impl(ExecutionContextScope * exe_scope,const char * key,ResultSet & results)105     bool Find_Impl(ExecutionContextScope *exe_scope, const char *key,
106                    ResultSet &results) override {
107       const bool append = false;
108       for (auto& scavenger : m_scavengers) {
109         if (scavenger && scavenger->Find(exe_scope, key, results, append))
110           return true;
111       }
112       return false;
113     }
114   private:
115     std::vector<std::shared_ptr<TypeScavenger>> m_scavengers;
116   };
117 
118   template <typename... ScavengerTypes>
119   class UnionTypeScavenger : public TypeScavenger {
120   public:
UnionTypeScavenger()121     UnionTypeScavenger() : TypeScavenger(), m_scavengers() {
122       for (std::shared_ptr<TypeScavenger> scavenger : { std::shared_ptr<TypeScavenger>(new ScavengerTypes())... }) {
123         if (scavenger)
124           m_scavengers.push_back(scavenger);
125       }
126     }
127   protected:
Find_Impl(ExecutionContextScope * exe_scope,const char * key,ResultSet & results)128     bool Find_Impl(ExecutionContextScope *exe_scope, const char *key,
129                    ResultSet &results) override {
130       const bool append = true;
131       bool success = false;
132       for (auto& scavenger : m_scavengers) {
133         if (scavenger)
134           success = scavenger->Find(exe_scope, key, results, append) || success;
135       }
136       return success;
137     }
138   private:
139     std::vector<std::shared_ptr<TypeScavenger>> m_scavengers;
140   };
141 
142   enum class FunctionNameRepresentation {
143     eName,
144     eNameWithArgs,
145     eNameWithNoArgs
146   };
147 
148   ~Language() override;
149 
150   static Language *FindPlugin(lldb::LanguageType language);
151 
152   /// Returns the Language associated with the given file path or a nullptr
153   /// if there is no known language.
154   static Language *FindPlugin(llvm::StringRef file_path);
155 
156   static Language *FindPlugin(lldb::LanguageType language,
157                               llvm::StringRef file_path);
158 
159   // return false from callback to stop iterating
160   static void ForEach(std::function<bool(Language *)> callback);
161 
162   virtual lldb::LanguageType GetLanguageType() const = 0;
163 
164   virtual bool IsTopLevelFunction(Function &function);
165 
166   virtual bool IsSourceFile(llvm::StringRef file_path) const = 0;
167 
GetHighlighter()168   virtual const Highlighter *GetHighlighter() const { return nullptr; }
169 
170   virtual lldb::TypeCategoryImplSP GetFormatters();
171 
172   virtual HardcodedFormatters::HardcodedFormatFinder GetHardcodedFormats();
173 
174   virtual HardcodedFormatters::HardcodedSummaryFinder GetHardcodedSummaries();
175 
176   virtual HardcodedFormatters::HardcodedSyntheticFinder
177   GetHardcodedSynthetics();
178 
179   virtual HardcodedFormatters::HardcodedValidatorFinder
180   GetHardcodedValidators();
181 
182   virtual std::vector<ConstString>
183   GetPossibleFormattersMatches(ValueObject &valobj,
184                                lldb::DynamicValueType use_dynamic);
185 
186   virtual lldb_private::formatters::StringPrinter::EscapingHelper
187       GetStringPrinterEscapingHelper(
188           lldb_private::formatters::StringPrinter::GetPrintableElementType);
189 
190   virtual std::unique_ptr<TypeScavenger> GetTypeScavenger();
191 
192   virtual const char *GetLanguageSpecificTypeLookupHelp();
193 
194   // if an individual data formatter can apply to several types and cross a
195   // language boundary it makes sense for individual languages to want to
196   // customize the printing of values of that type by appending proper
197   // prefix/suffix information in language-specific ways
198   virtual bool GetFormatterPrefixSuffix(ValueObject &valobj,
199                                         ConstString type_hint,
200                                         std::string &prefix,
201                                         std::string &suffix);
202 
203   // if a language has a custom format for printing variable declarations that
204   // it wants LLDB to honor it should return an appropriate closure here
205   virtual DumpValueObjectOptions::DeclPrintingHelper GetDeclPrintingHelper();
206 
207   virtual LazyBool IsLogicalTrue(ValueObject &valobj, Status &error);
208 
209   // for a ValueObject of some "reference type", if the value points to the
210   // nil/null object, this method returns true
211   virtual bool IsNilReference(ValueObject &valobj);
212 
213   // for a ValueObject of some "reference type", if the language provides a
214   // technique to decide whether the reference has ever been assigned to some
215   // object, this method will return true if such detection is possible, and if
216   // the reference has never been assigned
217   virtual bool IsUninitializedReference(ValueObject &valobj);
218 
219   virtual bool GetFunctionDisplayName(const SymbolContext *sc,
220                                       const ExecutionContext *exe_ctx,
221                                       FunctionNameRepresentation representation,
222                                       Stream &s);
223 
224   virtual void GetExceptionResolverDescription(bool catch_on, bool throw_on,
225                                                Stream &s);
226 
227   static void GetDefaultExceptionResolverDescription(bool catch_on,
228                                                      bool throw_on, Stream &s);
229 
230   // These are accessors for general information about the Languages lldb knows
231   // about:
232 
233   static lldb::LanguageType
234   GetLanguageTypeFromString(const char *string) = delete;
235   static lldb::LanguageType GetLanguageTypeFromString(llvm::StringRef string);
236 
237   static const char *GetNameForLanguageType(lldb::LanguageType language);
238 
239   static void PrintAllLanguages(Stream &s, const char *prefix,
240                                 const char *suffix);
241 
242   // return false from callback to stop iterating
243   static void ForAllLanguages(std::function<bool(lldb::LanguageType)> callback);
244 
245   static bool LanguageIsCPlusPlus(lldb::LanguageType language);
246 
247   static bool LanguageIsObjC(lldb::LanguageType language);
248 
249   static bool LanguageIsC(lldb::LanguageType language);
250 
251   static bool LanguageIsPascal(lldb::LanguageType language);
252 
253   // return the primary language, so if LanguageIsC(l), return eLanguageTypeC,
254   // etc.
255   static lldb::LanguageType GetPrimaryLanguage(lldb::LanguageType language);
256 
257   static void GetLanguagesSupportingTypeSystems(
258       std::set<lldb::LanguageType> &languages,
259       std::set<lldb::LanguageType> &languages_for_expressions);
260 
261   static void
262   GetLanguagesSupportingREPLs(std::set<lldb::LanguageType> &languages);
263 
264 protected:
265   //------------------------------------------------------------------
266   // Classes that inherit from Language can see and modify these
267   //------------------------------------------------------------------
268 
269   Language();
270 
271 private:
272   DISALLOW_COPY_AND_ASSIGN(Language);
273 };
274 
275 } // namespace lldb_private
276 
277 #endif // liblldb_Language_h_
278