1 //===-- BreakpointResolver.h ------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLDB_BREAKPOINT_BREAKPOINTRESOLVER_H
10 #define LLDB_BREAKPOINT_BREAKPOINTRESOLVER_H
11 
12 #include "lldb/Breakpoint/Breakpoint.h"
13 #include "lldb/Core/Address.h"
14 #include "lldb/Core/SearchFilter.h"
15 #include "lldb/Utility/ConstString.h"
16 #include "lldb/Utility/FileSpec.h"
17 #include "lldb/Utility/RegularExpression.h"
18 #include "lldb/lldb-private.h"
19 
20 namespace lldb_private {
21 
22 /// \class BreakpointResolver BreakpointResolver.h
23 /// "lldb/Breakpoint/BreakpointResolver.h" This class works with SearchFilter
24 /// to resolve logical breakpoints to their of concrete breakpoint locations.
25 
26 /// General Outline:
27 /// The BreakpointResolver is a Searcher.  In that protocol, the SearchFilter
28 /// asks the question "At what depth of the symbol context descent do you want
29 /// your callback to get called?" of the filter.  The resolver answers this
30 /// question (in the GetDepth method) and provides the resolution callback.
31 /// Each Breakpoint has a BreakpointResolver, and it calls either
32 /// ResolveBreakpoint or ResolveBreakpointInModules to tell it to look for new
33 /// breakpoint locations.
34 
35 class BreakpointResolver : public Searcher {
36   friend class Breakpoint;
37 
38 public:
39   /// The breakpoint resolver need to have a breakpoint for "ResolveBreakpoint
40   /// to make sense.  It can be constructed without a breakpoint, but you have
41   /// to call SetBreakpoint before ResolveBreakpoint.
42   ///
43   /// \param[in] bkpt
44   ///   The breakpoint that owns this resolver.
45   /// \param[in] resolverType
46   ///   The concrete breakpoint resolver type for this breakpoint.
47   BreakpointResolver(const lldb::BreakpointSP &bkpt,
48                      unsigned char resolverType,
49                      lldb::addr_t offset = 0);
50 
51   /// The Destructor is virtual, all significant breakpoint resolvers derive
52   /// from this class.
53   ~BreakpointResolver() override;
54 
55   /// This sets the breakpoint for this resolver.
56   ///
57   /// \param[in] bkpt
58   ///   The breakpoint that owns this resolver.
59   void SetBreakpoint(const lldb::BreakpointSP &bkpt);
60 
61   /// This gets the breakpoint for this resolver.
62   lldb::BreakpointSP GetBreakpoint() const {
63     auto breakpoint_sp = m_breakpoint.expired() ? lldb::BreakpointSP() :
64                                                   m_breakpoint.lock();
65     assert(breakpoint_sp);
66     return breakpoint_sp;
67   }
68 
69   /// This updates the offset for this breakpoint.  All the locations
70   /// currently set for this breakpoint will have their offset adjusted when
71   /// this is called.
72   ///
73   /// \param[in] offset
74   ///   The offset to add to all locations.
75   void SetOffset(lldb::addr_t offset);
76 
77   lldb::addr_t GetOffset() const { return m_offset; }
78 
79   /// In response to this method the resolver scans all the modules in the
80   /// breakpoint's target, and adds any new locations it finds.
81   ///
82   /// \param[in] filter
83   ///   The filter that will manage the search for this resolver.
84   virtual void ResolveBreakpoint(SearchFilter &filter);
85 
86   /// In response to this method the resolver scans the modules in the module
87   /// list \a modules, and adds any new locations it finds.
88   ///
89   /// \param[in] filter
90   ///   The filter that will manage the search for this resolver.
91   virtual void ResolveBreakpointInModules(SearchFilter &filter,
92                                           ModuleList &modules);
93 
94   /// Prints a canonical description for the breakpoint to the stream \a s.
95   ///
96   /// \param[in] s
97   ///   Stream to which the output is copied.
98   void GetDescription(Stream *s) override = 0;
99 
100   /// Standard "Dump" method.  At present it does nothing.
101   virtual void Dump(Stream *s) const = 0;
102 
103   /// This section handles serializing and deserializing from StructuredData
104   /// objects.
105 
106   static lldb::BreakpointResolverSP
107   CreateFromStructuredData(const StructuredData::Dictionary &resolver_dict,
108                            Status &error);
109 
110   virtual StructuredData::ObjectSP SerializeToStructuredData() {
111     return StructuredData::ObjectSP();
112   }
113 
114   static const char *GetSerializationKey() { return "BKPTResolver"; }
115 
116   static const char *GetSerializationSubclassKey() { return "Type"; }
117 
118   static const char *GetSerializationSubclassOptionsKey() { return "Options"; }
119 
120   StructuredData::DictionarySP
121   WrapOptionsDict(StructuredData::DictionarySP options_dict_sp);
122 
123   /// An enumeration for keeping track of the concrete subclass that is
124   /// actually instantiated. Values of this enumeration are kept in the
125   /// BreakpointResolver's SubclassID field. They are used for concrete type
126   /// identification.
127   enum ResolverTy {
128     FileLineResolver = 0, // This is an instance of BreakpointResolverFileLine
129     AddressResolver,      // This is an instance of BreakpointResolverAddress
130     NameResolver,         // This is an instance of BreakpointResolverName
131     FileRegexResolver,
132     PythonResolver,
133     ExceptionResolver,
134     LastKnownResolverType = ExceptionResolver,
135     UnknownResolver
136   };
137 
138   // Translate the Ty to name for serialization, the "+2" is one for size vrs.
139   // index, and one for UnknownResolver.
140   static const char *g_ty_to_name[LastKnownResolverType + 2];
141 
142   /// getResolverID - Return an ID for the concrete type of this object.  This
143   /// is used to implement the LLVM classof checks.  This should not be used
144   /// for any other purpose, as the values may change as LLDB evolves.
145   unsigned getResolverID() const { return SubclassID; }
146 
147   enum ResolverTy GetResolverTy() {
148     if (SubclassID > ResolverTy::LastKnownResolverType)
149       return ResolverTy::UnknownResolver;
150     else
151       return (enum ResolverTy)SubclassID;
152   }
153 
154   const char *GetResolverName() { return ResolverTyToName(GetResolverTy()); }
155 
156   static const char *ResolverTyToName(enum ResolverTy);
157 
158   static ResolverTy NameToResolverTy(llvm::StringRef name);
159 
160   virtual lldb::BreakpointResolverSP
161   CopyForBreakpoint(lldb::BreakpointSP &breakpoint) = 0;
162 
163 protected:
164   // Used for serializing resolver options:
165   // The options in this enum and the strings in the g_option_names must be
166   // kept in sync.
167   enum class OptionNames : uint32_t {
168     AddressOffset = 0,
169     ExactMatch,
170     FileName,
171     Inlines,
172     LanguageName,
173     LineNumber,
174     Column,
175     ModuleName,
176     NameMaskArray,
177     Offset,
178     PythonClassName,
179     RegexString,
180     ScriptArgs,
181     SectionName,
182     SearchDepth,
183     SkipPrologue,
184     SymbolNameArray,
185     LastOptionName
186   };
187   static const char
188       *g_option_names[static_cast<uint32_t>(OptionNames::LastOptionName)];
189 
190   virtual void NotifyBreakpointSet() {};
191 
192 public:
193   static const char *GetKey(OptionNames enum_value) {
194     return g_option_names[static_cast<uint32_t>(enum_value)];
195   }
196 
197 protected:
198   /// Takes a symbol context list of matches which supposedly represent the
199   /// same file and line number in a CU, and find the nearest actual line
200   /// number that matches, and then filter down the matching addresses to
201   /// unique entries, and skip the prologue if asked to do so, and then set
202   /// breakpoint locations in this breakpoint for all the resultant addresses.
203   /// When \p column is nonzero the \p line and \p column args are used to
204   /// filter the results to find the first breakpoint >= (line, column).
205   void SetSCMatchesByLine(SearchFilter &filter, SymbolContextList &sc_list,
206                           bool skip_prologue, llvm::StringRef log_ident,
207                           uint32_t line = 0,
208                           llvm::Optional<uint16_t> column = llvm::None);
209   void SetSCMatchesByLine(SearchFilter &, SymbolContextList &, bool,
210                           const char *) = delete;
211 
212   lldb::BreakpointLocationSP AddLocation(Address loc_addr,
213                                          bool *new_location = nullptr);
214 
215 private:
216   /// Helper for \p SetSCMatchesByLine.
217   void AddLocation(SearchFilter &filter, const SymbolContext &sc,
218                    bool skip_prologue, llvm::StringRef log_ident);
219 
220   lldb::BreakpointWP m_breakpoint; // This is the breakpoint we add locations to.
221   lldb::addr_t m_offset;    // A random offset the user asked us to add to any
222                             // breakpoints we set.
223 
224   // Subclass identifier (for llvm isa/dyn_cast)
225   const unsigned char SubclassID;
226   BreakpointResolver(const BreakpointResolver &) = delete;
227   const BreakpointResolver &operator=(const BreakpointResolver &) = delete;
228 };
229 
230 } // namespace lldb_private
231 
232 #endif // LLDB_BREAKPOINT_BREAKPOINTRESOLVER_H
233