[Reproducers] Make reproducer relocatable

Before this patch, reproducers weren't relocatable. The reproducer
contained hard coded paths in the VFS mapping, as well in the yaml file
listing the different input files for the command interpreter. This
patch changes that:

 - Use relative paths for the DataCollector.
 - Use an overlay prefix for the FileCollector.

Differential revision: https://reviews.llvm.org/D63467

llvm-svn: 363697

lldb/include/lldb/Utility/FileCollector.h

@@ -25,7 +25,7 @@ namespace lldb_private {
 /// the VFS.
 class FileCollector {
 public:
-  FileCollector(const FileSpec &root);
+  FileCollector(const FileSpec &root, const FileSpec &overlay);
 
   void AddFile(const llvm::Twine &file);
   void AddFile(const FileSpec &file) { return AddFile(file.GetPath()); }
@@ -59,6 +59,9 @@ class FileCollector {
   /// The root directory where files are copied.
   FileSpec m_root;
 
+  /// The root directory where the VFS overlay lives.
+  FileSpec m_overlay_root;
+
   /// Tracks already seen files so they can be skipped.
   llvm::StringSet<> m_seen;
 

lldb/include/lldb/Utility/Reproducer.h

@@ -91,7 +91,8 @@ class FileProvider : public Provider<FileProvider> {
 
   FileProvider(const FileSpec &directory)
       : Provider(directory),
-        m_collector(directory.CopyByAppendingPathComponent("root")) {}
+        m_collector(directory.CopyByAppendingPathComponent("root"), directory) {
+  }
 
   FileCollector &GetFileCollector() { return m_collector; }
 
@@ -132,8 +133,8 @@ class VersionProvider : public Provider<VersionProvider> {
 class DataRecorder {
 public:
   DataRecorder(const FileSpec &filename, std::error_code &ec)
-      : m_filename(std::move(filename)),
-        m_os(m_filename.GetPath(), ec, llvm::sys::fs::F_Text), m_record(true) {}
+      : m_filename(filename.GetFilename().GetStringRef()),
+        m_os(filename.GetPath(), ec, llvm::sys::fs::F_Text), m_record(true) {}
 
   static llvm::Expected<std::unique_ptr<DataRecorder>>
   Create(const FileSpec &filename);

lldb/lit/Reproducer/TestReuseDirectory.test

@@ -8,3 +8,10 @@
 # RUN: %lldb -x -b -s %S/Inputs/GDBRemoteCapture.in --capture --capture-path %t.repro %t.out | FileCheck %S/TestGDBRemoteRepro.test --check-prefix CHECK --check-prefix CAPTURE
 # RUN: %lldb -x -b -s %S/Inputs/GDBRemoteCapture.in --capture --capture-path %t.repro %t.out | FileCheck %S/TestGDBRemoteRepro.test --check-prefix CHECK --check-prefix CAPTURE
 # RUN: %lldb --replay %t.repro | FileCheck %S/TestGDBRemoteRepro.test --check-prefix CHECK --check-prefix REPLAY
+
+# Test that we can replay from a different location, i.e. that the reproducer
+# is relocatable.
+
+# RUN: rm -rf %t.repro_moved
+# RUN: mv %t.repro %t.repro_moved
+# RUN: %lldb --replay %t.repro_moved | FileCheck %S/TestGDBRemoteRepro.test --check-prefix CHECK --check-prefix REPLAY

lldb/source/API/SBDebugger.cpp

@@ -82,6 +82,12 @@ class CommandLoader {
     if (auto err = yin.error())
       return {};
 
+    for (auto &file : files) {
+      FileSpec absolute_path =
+          loader->GetRoot().CopyByAppendingPathComponent(file);
+      file = absolute_path.GetPath();
+    }
+
     return llvm::make_unique<CommandLoader>(std::move(files));
   }
 

lldb/source/Host/common/FileSystem.cpp

@@ -63,8 +63,9 @@ llvm::Error FileSystem::Initialize(const FileSpec &mapping) {
   if (!buffer)
     return llvm::errorCodeToError(buffer.getError());
 
-  InstanceImpl().emplace(
-      llvm::vfs::getVFSFromYAML(std::move(buffer.get()), nullptr, ""), true);
+  InstanceImpl().emplace(llvm::vfs::getVFSFromYAML(std::move(buffer.get()),
+                                                   nullptr, mapping.GetPath()),
+                         true);
 
   return llvm::Error::success();
 }

lldb/source/Utility/FileCollector.cpp

@@ -33,7 +33,8 @@ static bool IsCaseSensitivePath(StringRef path) {
   return true;
 }
 
-FileCollector::FileCollector(const FileSpec &root) : m_root(root) {
+FileCollector::FileCollector(const FileSpec &root, const FileSpec &overlay_root)
+    : m_root(root), m_overlay_root(overlay_root) {
   sys::fs::create_directories(m_root.GetPath(), true);
 }
 
@@ -133,7 +134,9 @@ std::error_code FileCollector::CopyFiles(bool stop_on_error) {
 std::error_code FileCollector::WriteMapping(const FileSpec &mapping_file) {
   std::lock_guard<std::mutex> lock(m_mutex);
 
-  const std::string root = m_root.GetPath();
+  llvm::StringRef root = m_overlay_root.GetPath();
+
+  m_vfs_writer.setOverlayDir(root);
   m_vfs_writer.setCaseSensitivity(IsCaseSensitivePath(root));
   m_vfs_writer.setUseExternalNames(false);
 

lldb/unittests/Utility/FileCollectorTest.cpp

@@ -105,7 +105,7 @@ struct ScopedFile {
 TEST(FileCollectorTest, AddFile) {
   ScopedDir root("add_file_root", true);
   FileSpec root_fs(root.Path);
-  TestingFileCollector file_collector(root_fs);
+  TestingFileCollector file_collector(root_fs, root_fs);
 
   file_collector.AddFile(FileSpec("/path/to/a"));
   file_collector.AddFile(FileSpec("/path/to/b"));
@@ -132,7 +132,7 @@ TEST(FileCollectorTest, CopyFiles) {
   // Create file collector and add files.
   ScopedDir root("copy_files_root", true);
   FileSpec root_fs(root.Path);
-  TestingFileCollector file_collector(root_fs);
+  TestingFileCollector file_collector(root_fs, root_fs);
   file_collector.AddFile(a.Path);
   file_collector.AddFile(b.Path);
   file_collector.AddFile(c.Path);
@@ -174,7 +174,7 @@ TEST(FileCollectorTest, Symlinks) {
   // Root where files are copied to.
   ScopedDir reproducer_root("reproducer_root", true);
   FileSpec root_fs(reproducer_root.Path);
-  TestingFileCollector file_collector(root_fs);
+  TestingFileCollector file_collector(root_fs, root_fs);
 
   // Add all the files to the collector.
   file_collector.AddFile(a.Path);