Reapply "[llvm-cov] Add an -output-dir option for the show sub-command""

Passing -output-dir path/to/dir to llvm-cov show creates path/to/dir if
it doesn't already exist, and prints reports into that directory.

In function view mode, all views are written into
path/to/dir/functions.$EXTENSION. In file view mode, all views are
written into path/to/dir/coverage/$PATH.$EXTENSION.

Changes since the initial commit:

- Avoid accidentally closing stdout twice.

llvm-svn: 273985

1 files changed, 47 insertions, 0 deletions

diff --git a/llvm/tools/llvm-cov/SourceCoverageView.cpp b/llvm/tools/llvm-cov/SourceCoverageView.cpp
index 3309189a935..f9ce946dc5f 100644
--- a/llvm/tools/llvm-cov/SourceCoverageView.cpp
+++ b/llvm/tools/llvm-cov/SourceCoverageView.cpp
@@ -15,7 +15,9 @@
 #include "SourceCoverageViewText.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/FileSystem.h"
 #include "llvm/Support/LineIterator.h"
+#include "llvm/Support/Path.h"
 
 using namespace llvm;
 
@@ -34,6 +36,51 @@ std::string SourceCoverageView::formatCount(uint64_t N) {
   return Result;
 }
 
+void SourceCoverageView::StreamDestructor::operator()(raw_ostream *OS) const {
+  if (OS == &outs())
+    return;
+  delete OS;
+}
+
+/// \brief Create a file at ``Dir/ToplevelDir/@Path.Extension``. If
+/// \p ToplevelDir is empty, its path component is skipped.
+static Expected<SourceCoverageView::OwnedStream>
+createFileInDirectory(StringRef Dir, StringRef ToplevelDir, StringRef Path,
+                      StringRef Extension) {
+  assert(Extension.size() && "The file extension may not be empty");
+
+  SmallString<256> FullPath(Dir);
+  if (!ToplevelDir.empty())
+    sys::path::append(FullPath, ToplevelDir);
+
+  auto PathBaseDir = sys::path::relative_path(sys::path::parent_path(Path));
+  sys::path::append(FullPath, PathBaseDir);
+
+  if (auto E = sys::fs::create_directories(FullPath))
+    return errorCodeToError(E);
+
+  auto PathFilename = (sys::path::filename(Path) + "." + Extension).str();
+  sys::path::append(FullPath, PathFilename);
+
+  std::error_code E;
+  auto OS = SourceCoverageView::OwnedStream(
+      new raw_fd_ostream(FullPath, E, sys::fs::F_RW));
+  if (E)
+    return errorCodeToError(E);
+  return std::move(OS);
+}
+
+Expected<SourceCoverageView::OwnedStream>
+SourceCoverageView::createOutputStream(const CoverageViewOptions &Opts,
+                                       StringRef Path, StringRef Extension,
+                                       bool InToplevel) {
+  if (Opts.ShowOutputDirectory == "")
+    return OwnedStream(&outs());
+
+  return createFileInDirectory(Opts.ShowOutputDirectory,
+                               InToplevel ? "" : "coverage", Path, Extension);
+}
+
 void SourceCoverageView::addExpansion(
     const coverage::CounterMappingRegion &Region,
     std::unique_ptr<SourceCoverageView> View) {