llvm/lib/ObjectYAML/MinidumpEmitter.cpp

   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 #include <optional>
  14
  15 using namespace llvm;
  16 using namespace llvm::minidump;
  17 using namespace llvm::MinidumpYAML;
  18
  19 namespace {
  20 /// A helper class to manage the placement of various structures into the final
  21 /// minidump binary. Space for objects can be allocated via various allocate***
  22 /// methods, while the final minidump file is written by calling the writeTo
  23 /// method. The plain versions of allocation functions take a reference to the
  24 /// data which is to be written (and hence the data must be available until
  25 /// writeTo is called), while the "New" versions allocate the data in an
  26 /// allocator-managed buffer, which is available until the allocator object is
  27 /// destroyed. For both kinds of functions, it is possible to modify the
  28 /// data for which the space has been "allocated" until the final writeTo call.
  29 /// This is useful for "linking" the allocated structures via their offsets.
  30 class BlobAllocator {
  31 public:
  32   size_t tell() const { return NextOffset; }
  33
  34   size_t allocateCallback(size_t Size,
  35                           std::function<void(raw_ostream &)> Callback) {
  36     size_t Offset = NextOffset;
  37     NextOffset += Size;
  38     Callbacks.push_back(std::move(Callback));
  39     return Offset;
  40   }
  41
  42   size_t allocateBytes(ArrayRef<uint8_t> Data) {
  43     return allocateCallback(
  44         Data.size(), [Data](raw_ostream &OS) { OS << toStringRef(Data); });
  45   }
  46
  47   size_t allocateBytes(yaml::BinaryRef Data) {
  48     return allocateCallback(Data.binary_size(), [Data](raw_ostream &OS) {
  49       Data.writeAsBinary(OS);
  50     });
  51   }
  52
  53   template <typename T> size_t allocateArray(ArrayRef<T> Data) {
  54     return allocateBytes({reinterpret_cast<const uint8_t *>(Data.data()),
  55                           sizeof(T) * Data.size()});
  56   }
  57
  58   template <typename T, typename RangeType>
  59   std::pair<size_t, MutableArrayRef<T>>
  60   allocateNewArray(const iterator_range<RangeType> &Range);
  61
  62   template <typename T> size_t allocateObject(const T &Data) {
  63     return allocateArray(ArrayRef(Data));
  64   }
  65
  66   template <typename T, typename... Types>
  67   std::pair<size_t, T *> allocateNewObject(Types &&... Args) {
  68     T *Object = new (Temporaries.Allocate<T>()) T(std::forward<Types>(Args)...);
  69     return {allocateObject(*Object), Object};
  70   }
  71
  72   size_t allocateString(StringRef Str);
  73
  74   void writeTo(raw_ostream &OS) const;
  75
  76 private:
  77   size_t NextOffset = 0;
  78
  79   BumpPtrAllocator Temporaries;
  80   std::vector<std::function<void(raw_ostream &)>> Callbacks;
  81 };
  82 } // namespace
  83
  84 template <typename T, typename RangeType>
  85 std::pair<size_t, MutableArrayRef<T>>
  86 BlobAllocator::allocateNewArray(const iterator_range<RangeType> &Range) {
  87   size_t Num = std::distance(Range.begin(), Range.end());
  88   MutableArrayRef<T> Array(Temporaries.Allocate<T>(Num), Num);
  89   std::uninitialized_copy(Range.begin(), Range.end(), Array.begin());
  90   return {allocateArray(Array), Array};
  91 }
  92
  93 size_t BlobAllocator::allocateString(StringRef Str) {
  94   SmallVector<UTF16, 32> WStr;
  95   bool OK = convertUTF8ToUTF16String(Str, WStr);
  96   assert(OK && "Invalid UTF8 in Str?");
  97   (void)OK;
  98
  99   // The utf16 string is null-terminated, but the terminator is not counted in
 100   // the string size.
 101   WStr.push_back(0);
 102   size_t Result =
 103       allocateNewObject<support::ulittle32_t>(2 * (WStr.size() - 1)).first;
 104   allocateNewArray<support::ulittle16_t>(make_range(WStr.begin(), WStr.end()));
 105   return Result;
 106 }
 107
 108 void BlobAllocator::writeTo(raw_ostream &OS) const {
 109   size_t BeginOffset = OS.tell();
 110   for (const auto &Callback : Callbacks)
 111     Callback(OS);
 112   assert(OS.tell() == BeginOffset + NextOffset &&
 113          "Callbacks wrote an unexpected number of bytes.");
 114   (void)BeginOffset;
 115 }
 116
 117 static LocationDescriptor layout(BlobAllocator &File, yaml::BinaryRef Data) {
 118   return {support::ulittle32_t(Data.binary_size()),
 119           support::ulittle32_t(File.allocateBytes(Data))};
 120 }
 121
 122 static size_t layout(BlobAllocator &File, MinidumpYAML::ExceptionStream &S) {
 123   File.allocateObject(S.MDExceptionStream);
 124
 125   size_t DataEnd = File.tell();
 126
 127   // Lay out the thread context data, (which is not a part of the stream).
 128   // TODO: This usually (always?) matches the thread context of the
 129   // corresponding thread, and may overlap memory regions as well.  We could
 130   // add a level of indirection to the MinidumpYAML format (like an array of
 131   // Blobs that the LocationDescriptors index into) to be able to distinguish
 132   // the cases where location descriptions overlap vs happen to reference
 133   // identical data.
 134   S.MDExceptionStream.ThreadContext = layout(File, S.ThreadContext);
 135
 136   return DataEnd;
 137 }
 138
 139 static void layout(BlobAllocator &File, MemoryListStream::entry_type &Range) {
 140   Range.Entry.Memory = layout(File, Range.Content);
 141 }
 142
 143 static void layout(BlobAllocator &File, ModuleListStream::entry_type &M) {
 144   M.Entry.ModuleNameRVA = File.allocateString(M.Name);
 145
 146   M.Entry.CvRecord = layout(File, M.CvRecord);
 147   M.Entry.MiscRecord = layout(File, M.MiscRecord);
 148 }
 149
 150 static void layout(BlobAllocator &File, ThreadListStream::entry_type &T) {
 151   T.Entry.Stack.Memory = layout(File, T.Stack);
 152   T.Entry.Context = layout(File, T.Context);
 153 }
 154
 155 template <typename EntryT>
 156 static size_t layout(BlobAllocator &File,
 157                      MinidumpYAML::detail::ListStream<EntryT> &S) {
 158
 159   File.allocateNewObject<support::ulittle32_t>(S.Entries.size());
 160   for (auto &E : S.Entries)
 161     File.allocateObject(E.Entry);
 162
 163   size_t DataEnd = File.tell();
 164
 165   // Lay out the auxiliary data, (which is not a part of the stream).
 166   DataEnd = File.tell();
 167   for (auto &E : S.Entries)
 168     layout(File, E);
 169
 170   return DataEnd;
 171 }
 172
 173 static Directory layout(BlobAllocator &File, Stream &S) {
 174   Directory Result;
 175   Result.Type = S.Type;
 176   Result.Location.RVA = File.tell();
 177   std::optional<size_t> DataEnd;
 178   switch (S.Kind) {
 179   case Stream::StreamKind::Exception:
 180     DataEnd = layout(File, cast<MinidumpYAML::ExceptionStream>(S));
 181     break;
 182   case Stream::StreamKind::MemoryInfoList: {
 183     MemoryInfoListStream &InfoList = cast<MemoryInfoListStream>(S);
 184     File.allocateNewObject<minidump::MemoryInfoListHeader>(
 185         sizeof(minidump::MemoryInfoListHeader), sizeof(minidump::MemoryInfo),
 186         InfoList.Infos.size());
 187     File.allocateArray(ArrayRef(InfoList.Infos));
 188     break;
 189   }
 190   case Stream::StreamKind::MemoryList:
 191     DataEnd = layout(File, cast<MemoryListStream>(S));
 192     break;
 193   case Stream::StreamKind::ModuleList:
 194     DataEnd = layout(File, cast<ModuleListStream>(S));
 195     break;
 196   case Stream::StreamKind::RawContent: {
 197     RawContentStream &Raw = cast<RawContentStream>(S);
 198     File.allocateCallback(Raw.Size, [&Raw](raw_ostream &OS) {
 199       Raw.Content.writeAsBinary(OS);
 200       assert(Raw.Content.binary_size() <= Raw.Size);
 201       OS << std::string(Raw.Size - Raw.Content.binary_size(), '\0');
 202     });
 203     break;
 204   }
 205   case Stream::StreamKind::SystemInfo: {
 206     SystemInfoStream &SystemInfo = cast<SystemInfoStream>(S);
 207     File.allocateObject(SystemInfo.Info);
 208     // The CSD string is not a part of the stream.
 209     DataEnd = File.tell();
 210     SystemInfo.Info.CSDVersionRVA = File.allocateString(SystemInfo.CSDVersion);
 211     break;
 212   }
 213   case Stream::StreamKind::TextContent:
 214     File.allocateArray(arrayRefFromStringRef(cast<TextContentStream>(S).Text));
 215     break;
 216   case Stream::StreamKind::ThreadList:
 217     DataEnd = layout(File, cast<ThreadListStream>(S));
 218     break;
 219   }
 220   // If DataEnd is not set, we assume everything we generated is a part of the
 221   // stream.
 222   Result.Location.DataSize =
 223       DataEnd.value_or(File.tell()) - Result.Location.RVA;
 224   return Result;
 225 }
 226
 227 namespace llvm {
 228 namespace yaml {
 229
 230 bool yaml2minidump(MinidumpYAML::Object &Obj, raw_ostream &Out,
 231                    ErrorHandler /*EH*/) {
 232   BlobAllocator File;
 233   File.allocateObject(Obj.Header);
 234
 235   std::vector<Directory> StreamDirectory(Obj.Streams.size());
 236   Obj.Header.StreamDirectoryRVA = File.allocateArray(ArrayRef(StreamDirectory));
 237   Obj.Header.NumberOfStreams = StreamDirectory.size();
 238
 239   for (const auto &[Index, Stream] : enumerate(Obj.Streams))
 240     StreamDirectory[Index] = layout(File, *Stream);
 241
 242   File.writeTo(Out);
 243   return true;
 244 }
 245
 246 } // namespace yaml
 247 } // namespace llvm