1 //===- TBEHandler.cpp -----------------------------------------------------===//
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 #include "llvm/InterfaceStub/TBEHandler.h"
10 #include "llvm/ADT/StringRef.h"
11 #include "llvm/ADT/StringSwitch.h"
12 #include "llvm/InterfaceStub/ELFStub.h"
13 #include "llvm/Support/Error.h"
14 #include "llvm/Support/YAMLTraits.h"
15 
16 using namespace llvm;
17 using namespace llvm::elfabi;
18 
19 LLVM_YAML_STRONG_TYPEDEF(ELFArch, ELFArchMapper)
20 
21 namespace llvm {
22 namespace yaml {
23 
24 /// YAML traits for ELFSymbolType.
25 template <> struct ScalarEnumerationTraits<ELFSymbolType> {
enumerationllvm::yaml::ScalarEnumerationTraits26   static void enumeration(IO &IO, ELFSymbolType &SymbolType) {
27     IO.enumCase(SymbolType, "NoType", ELFSymbolType::NoType);
28     IO.enumCase(SymbolType, "Func", ELFSymbolType::Func);
29     IO.enumCase(SymbolType, "Object", ELFSymbolType::Object);
30     IO.enumCase(SymbolType, "TLS", ELFSymbolType::TLS);
31     IO.enumCase(SymbolType, "Unknown", ELFSymbolType::Unknown);
32     // Treat other symbol types as noise, and map to Unknown.
33     if (!IO.outputting() && IO.matchEnumFallback())
34       SymbolType = ELFSymbolType::Unknown;
35   }
36 };
37 
38 /// YAML traits for ELFArch.
39 template <> struct ScalarTraits<ELFArchMapper> {
outputllvm::yaml::ScalarTraits40   static void output(const ELFArchMapper &Value, void *,
41                      llvm::raw_ostream &Out) {
42     // Map from integer to architecture string.
43     switch (Value) {
44     case (ELFArch)ELF::EM_X86_64:
45       Out << "x86_64";
46       break;
47     case (ELFArch)ELF::EM_AARCH64:
48       Out << "AArch64";
49       break;
50     case (ELFArch)ELF::EM_NONE:
51     default:
52       Out << "Unknown";
53     }
54   }
55 
inputllvm::yaml::ScalarTraits56   static StringRef input(StringRef Scalar, void *, ELFArchMapper &Value) {
57     // Map from architecture string to integer.
58     Value = StringSwitch<ELFArch>(Scalar)
59                 .Case("x86_64", ELF::EM_X86_64)
60                 .Case("AArch64", ELF::EM_AARCH64)
61                 .Case("Unknown", ELF::EM_NONE)
62                 .Default(ELF::EM_NONE);
63 
64     // Returning empty StringRef indicates successful parse.
65     return StringRef();
66   }
67 
68   // Don't place quotation marks around architecture value.
mustQuotellvm::yaml::ScalarTraits69   static QuotingType mustQuote(StringRef) { return QuotingType::None; }
70 };
71 
72 /// YAML traits for ELFSymbol.
73 template <> struct MappingTraits<ELFSymbol> {
mappingllvm::yaml::MappingTraits74   static void mapping(IO &IO, ELFSymbol &Symbol) {
75     IO.mapRequired("Type", Symbol.Type);
76     // The need for symbol size depends on the symbol type.
77     if (Symbol.Type == ELFSymbolType::NoType) {
78       IO.mapOptional("Size", Symbol.Size, (uint64_t)0);
79     } else if (Symbol.Type == ELFSymbolType::Func) {
80       Symbol.Size = 0;
81     } else {
82       IO.mapRequired("Size", Symbol.Size);
83     }
84     IO.mapOptional("Undefined", Symbol.Undefined, false);
85     IO.mapOptional("Weak", Symbol.Weak, false);
86     IO.mapOptional("Warning", Symbol.Warning);
87   }
88 
89   // Compacts symbol information into a single line.
90   static const bool flow = true;
91 };
92 
93 /// YAML traits for set of ELFSymbols.
94 template <> struct CustomMappingTraits<std::set<ELFSymbol>> {
inputOnellvm::yaml::CustomMappingTraits95   static void inputOne(IO &IO, StringRef Key, std::set<ELFSymbol> &Set) {
96     ELFSymbol Sym(Key.str());
97     IO.mapRequired(Key.str().c_str(), Sym);
98     Set.insert(Sym);
99   }
100 
outputllvm::yaml::CustomMappingTraits101   static void output(IO &IO, std::set<ELFSymbol> &Set) {
102     for (auto &Sym : Set)
103       IO.mapRequired(Sym.Name.c_str(), const_cast<ELFSymbol &>(Sym));
104   }
105 };
106 
107 /// YAML traits for ELFStub objects.
108 template <> struct MappingTraits<ELFStub> {
mappingllvm::yaml::MappingTraits109   static void mapping(IO &IO, ELFStub &Stub) {
110     if (!IO.mapTag("!tapi-tbe", true))
111       IO.setError("Not a .tbe YAML file.");
112     IO.mapRequired("TbeVersion", Stub.TbeVersion);
113     IO.mapOptional("SoName", Stub.SoName);
114     IO.mapRequired("Arch", (ELFArchMapper &)Stub.Arch);
115     IO.mapOptional("NeededLibs", Stub.NeededLibs);
116     IO.mapRequired("Symbols", Stub.Symbols);
117   }
118 };
119 
120 } // end namespace yaml
121 } // end namespace llvm
122 
readTBEFromBuffer(StringRef Buf)123 Expected<std::unique_ptr<ELFStub>> elfabi::readTBEFromBuffer(StringRef Buf) {
124   yaml::Input YamlIn(Buf);
125   std::unique_ptr<ELFStub> Stub(new ELFStub());
126   YamlIn >> *Stub;
127   if (std::error_code Err = YamlIn.error())
128     return createStringError(Err, "YAML failed reading as TBE");
129 
130   if (Stub->TbeVersion > elfabi::TBEVersionCurrent)
131     return make_error<StringError>(
132         "TBE version " + Stub->TbeVersion.getAsString() + " is unsupported.",
133         std::make_error_code(std::errc::invalid_argument));
134 
135   return std::move(Stub);
136 }
137 
writeTBEToOutputStream(raw_ostream & OS,const ELFStub & Stub)138 Error elfabi::writeTBEToOutputStream(raw_ostream &OS, const ELFStub &Stub) {
139   yaml::Output YamlOut(OS, NULL, /*WrapColumn =*/0);
140 
141   YamlOut << const_cast<ELFStub &>(Stub);
142   return Error::success();
143 }
144