1 //===- yaml2minidump.cpp - Convert a YAML file to a minidump file ---------===//
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/ObjectYAML/MinidumpYAML.h"
10 #include "llvm/ObjectYAML/yaml2obj.h"
11 #include "llvm/Support/ConvertUTF.h"
12 #include "llvm/Support/raw_ostream.h"
13 
14 using namespace llvm;
15 using namespace llvm::minidump;
16 using namespace llvm::MinidumpYAML;
17 
18 namespace {
19 /// A helper class to manage the placement of various structures into the final
20 /// minidump binary. Space for objects can be allocated via various allocate***
21 /// methods, while the final minidump file is written by calling the writeTo
22 /// method. The plain versions of allocation functions take a reference to the
23 /// data which is to be written (and hence the data must be available until
24 /// writeTo is called), while the "New" versions allocate the data in an
25 /// allocator-managed buffer, which is available until the allocator object is
26 /// destroyed. For both kinds of functions, it is possible to modify the
27 /// data for which the space has been "allocated" until the final writeTo call.
28 /// This is useful for "linking" the allocated structures via their offsets.
29 class BlobAllocator {
30 public:
31   size_t tell() const { return NextOffset; }
32 
33   size_t allocateCallback(size_t Size,
34                           std::function<void(raw_ostream &)> Callback) {
35     size_t Offset = NextOffset;
36     NextOffset += Size;
37     Callbacks.push_back(std::move(Callback));
38     return Offset;
39   }
40 
41   size_t allocateBytes(ArrayRef<uint8_t> Data) {
42     return allocateCallback(
43         Data.size(), [Data](raw_ostream &OS) { OS << toStringRef(Data); });
44   }
45 
46   size_t allocateBytes(yaml::BinaryRef Data) {
47     return allocateCallback(Data.binary_size(), [Data](raw_ostream &OS) {
48       Data.writeAsBinary(OS);
49     });
50   }
51 
52   template <typename T> size_t allocateArray(ArrayRef<T> Data) {
53     return allocateBytes({reinterpret_cast<const uint8_t *>(Data.data()),
54                           sizeof(T) * Data.size()});
55   }
56 
57   template <typename T, typename RangeType>
58   std::pair<size_t, MutableArrayRef<T>>
59   allocateNewArray(const iterator_range<RangeType> &Range);
60 
61   template <typename T> size_t allocateObject(const T &Data) {
62     return allocateArray(makeArrayRef(Data));
63   }
64 
65   template <typename T, typename... Types>
66   std::pair<size_t, T *> allocateNewObject(Types &&... Args) {
67     T *Object = new (Temporaries.Allocate<T>()) T(std::forward<Types>(Args)...);
68     return {allocateObject(*Object), Object};
69   }
70 
71   size_t allocateString(StringRef Str);
72 
73   void writeTo(raw_ostream &OS) const;
74 
75 private:
76   size_t NextOffset = 0;
77 
78   BumpPtrAllocator Temporaries;
79   std::vector<std::function<void(raw_ostream &)>> Callbacks;
80 };
81 } // namespace
82 
83 template <typename T, typename RangeType>
84 std::pair<size_t, MutableArrayRef<T>>
85 BlobAllocator::allocateNewArray(const iterator_range<RangeType> &Range) {
86   size_t Num = std::distance(Range.begin(), Range.end());
87   MutableArrayRef<T> Array(Temporaries.Allocate<T>(Num), Num);
88   std::uninitialized_copy(Range.begin(), Range.end(), Array.begin());
89   return {allocateArray(Array), Array};
90 }
91 
92 size_t BlobAllocator::allocateString(StringRef Str) {
93   SmallVector<UTF16, 32> WStr;
94   bool OK = convertUTF8ToUTF16String(Str, WStr);
95   assert(OK && "Invalid UTF8 in Str?");
96   (void)OK;
97 
98   // The utf16 string is null-terminated, but the terminator is not counted in
99   // the string size.
100   WStr.push_back(0);
101   size_t Result =
102       allocateNewObject<support::ulittle32_t>(2 * (WStr.size() - 1)).first;
103   allocateNewArray<support::ulittle16_t>(make_range(WStr.begin(), WStr.end()));
104   return Result;
105 }
106 
107 void BlobAllocator::writeTo(raw_ostream &OS) const {
108   size_t BeginOffset = OS.tell();
109   for (const auto &Callback : Callbacks)
110     Callback(OS);
111   assert(OS.tell() == BeginOffset + NextOffset &&
112          "Callbacks wrote an unexpected number of bytes.");
113   (void)BeginOffset;
114 }
115 
116 static LocationDescriptor layout(BlobAllocator &File, yaml::BinaryRef Data) {
117   return {support::ulittle32_t(Data.binary_size()),
118           support::ulittle32_t(File.allocateBytes(Data))};
119 }
120 
121 static void layout(BlobAllocator &File, MemoryListStream::entry_type &Range) {
122   Range.Entry.Memory = layout(File, Range.Content);
123 }
124 
125 static void layout(BlobAllocator &File, ModuleListStream::entry_type &M) {
126   M.Entry.ModuleNameRVA = File.allocateString(M.Name);
127 
128   M.Entry.CvRecord = layout(File, M.CvRecord);
129   M.Entry.MiscRecord = layout(File, M.MiscRecord);
130 }
131 
132 static void layout(BlobAllocator &File, ThreadListStream::entry_type &T) {
133   T.Entry.Stack.Memory = layout(File, T.Stack);
134   T.Entry.Context = layout(File, T.Context);
135 }
136 
137 template <typename EntryT>
138 static size_t layout(BlobAllocator &File,
139                      MinidumpYAML::detail::ListStream<EntryT> &S) {
140 
141   File.allocateNewObject<support::ulittle32_t>(S.Entries.size());
142   for (auto &E : S.Entries)
143     File.allocateObject(E.Entry);
144 
145   size_t DataEnd = File.tell();
146 
147   // Lay out the auxiliary data, (which is not a part of the stream).
148   DataEnd = File.tell();
149   for (auto &E : S.Entries)
150     layout(File, E);
151 
152   return DataEnd;
153 }
154 
155 static Directory layout(BlobAllocator &File, Stream &S) {
156   Directory Result;
157   Result.Type = S.Type;
158   Result.Location.RVA = File.tell();
159   Optional<size_t> DataEnd;
160   switch (S.Kind) {
161   case Stream::StreamKind::MemoryList:
162     DataEnd = layout(File, cast<MemoryListStream>(S));
163     break;
164   case Stream::StreamKind::ModuleList:
165     DataEnd = layout(File, cast<ModuleListStream>(S));
166     break;
167   case Stream::StreamKind::RawContent: {
168     RawContentStream &Raw = cast<RawContentStream>(S);
169     File.allocateCallback(Raw.Size, [&Raw](raw_ostream &OS) {
170       Raw.Content.writeAsBinary(OS);
171       assert(Raw.Content.binary_size() <= Raw.Size);
172       OS << std::string(Raw.Size - Raw.Content.binary_size(), '\0');
173     });
174     break;
175   }
176   case Stream::StreamKind::SystemInfo: {
177     SystemInfoStream &SystemInfo = cast<SystemInfoStream>(S);
178     File.allocateObject(SystemInfo.Info);
179     // The CSD string is not a part of the stream.
180     DataEnd = File.tell();
181     SystemInfo.Info.CSDVersionRVA = File.allocateString(SystemInfo.CSDVersion);
182     break;
183   }
184   case Stream::StreamKind::TextContent:
185     File.allocateArray(arrayRefFromStringRef(cast<TextContentStream>(S).Text));
186     break;
187   case Stream::StreamKind::ThreadList:
188     DataEnd = layout(File, cast<ThreadListStream>(S));
189     break;
190   }
191   // If DataEnd is not set, we assume everything we generated is a part of the
192   // stream.
193   Result.Location.DataSize =
194       DataEnd.getValueOr(File.tell()) - Result.Location.RVA;
195   return Result;
196 }
197 
198 namespace llvm {
199 namespace yaml {
200 
201 bool yaml2minidump(MinidumpYAML::Object &Obj, raw_ostream &Out,
202                    ErrorHandler /*EH*/) {
203   BlobAllocator File;
204   File.allocateObject(Obj.Header);
205 
206   std::vector<Directory> StreamDirectory(Obj.Streams.size());
207   Obj.Header.StreamDirectoryRVA =
208       File.allocateArray(makeArrayRef(StreamDirectory));
209   Obj.Header.NumberOfStreams = StreamDirectory.size();
210 
211   for (auto &Stream : enumerate(Obj.Streams))
212     StreamDirectory[Stream.index()] = layout(File, *Stream.value());
213 
214   File.writeTo(Out);
215   return true;
216 }
217 
218 } // namespace yaml
219 } // namespace llvm
220