1 files changed, 191 insertions, 0 deletions
diff --git a/libbuild2/file-cache.ixx b/libbuild2/file-cache.ixx
new file mode 100644
index 0000000..99be5ad
--- /dev/null
+++ b/libbuild2/file-cache.ixx
@@ -0,0 +1,191 @@
+// file      : libbuild2/file-cache.ixx -*- C++ -*-
+// license   : MIT; see accompanying LICENSE file
+
+namespace build2
+{
+  // file_cache::entry
+  //
+  inline const path& file_cache::entry::
+  path () const
+  {
+    return path_;
+  }
+
+  inline void file_cache::entry::
+  pin ()
+  {
+    ++pin_;
+  }
+
+  inline void file_cache::entry::
+  unpin ()
+  {
+    if (--pin_ == 0          &&
+        !comp_path_.empty () &&
+        (state_ == uncomp || state_ == decomp))
+      preempt ();
+  }
+
+  inline file_cache::read file_cache::entry::
+  open ()
+  {
+    assert (state_ != null && state_ != uninit);
+
+    if (state_ == comp)
+    {
+      decompress ();
+      state_ = decomp;
+    }
+
+    pin ();
+    return read (*this);
+  }
+
+  inline file_cache::entry::
+  operator bool () const
+  {
+    return state_ != null;
+  }
+
+  inline file_cache::entry::
+  entry (path_type p, bool t, bool c)
+      : temporary (t),
+        state_ (uninit),
+        path_ (move (p)),
+        comp_path_ (c ? path_ + ".lz4" : path_type ()),
+        pin_ (1)
+  {
+  }
+
+  inline file_cache::entry::
+  ~entry ()
+  {
+    if (state_ != null && temporary)
+      remove ();
+  }
+
+  inline file_cache::entry::
+  entry (entry&& e) noexcept
+      : temporary (e.temporary),
+        state_ (e.state_),
+        path_ (move (e.path_)),
+        comp_path_ (move (e.comp_path_)),
+        pin_ (e.pin_)
+  {
+    e.state_ = null;
+  }
+
+  inline file_cache::entry& file_cache::entry::
+  operator= (entry&& e) noexcept
+  {
+    if (this != &e)
+    {
+      assert (state_ == null);
+
+      temporary = e.temporary;
+      state_ = e.state_;
+      path_ = move (e.path_);
+      comp_path_ = move (e.comp_path_);
+      pin_ = e.pin_;
+
+      e.state_ = null;
+    }
+    return *this;
+  }
+
+  // file_cache::write
+  //
+  inline void file_cache::write::
+  close ()
+  {
+    entry_->state_ = entry::uncomp;
+  }
+
+  inline file_cache::write::
+  ~write ()
+  {
+    if (entry_ != nullptr)
+      entry_->unpin ();
+  }
+
+  inline file_cache::write::
+  write (write&& e) noexcept
+      : entry_ (e.entry_)
+  {
+    e.entry_ = nullptr;
+  }
+
+  inline file_cache::write& file_cache::write::
+  operator= (write&& e) noexcept
+  {
+    if (this != &e)
+    {
+      assert (entry_ == nullptr);
+      swap (entry_, e.entry_);
+    }
+    return *this;
+  }
+
+  // file_cache::read
+  //
+  inline file_cache::read::
+  ~read ()
+  {
+    if (entry_ != nullptr)
+      entry_->unpin ();
+  }
+
+  inline file_cache::read::
+  read (read&& e) noexcept
+      : entry_ (e.entry_)
+  {
+    e.entry_ = nullptr;
+  }
+
+  inline file_cache::read& file_cache::read::
+  operator= (read&& e) noexcept
+  {
+    if (this != &e)
+    {
+      assert (entry_ == nullptr);
+      swap (entry_, e.entry_);
+    }
+    return *this;
+  }
+
+  // file_cache
+  //
+  inline file_cache::entry file_cache::
+  create (path f, optional<bool>)
+  {
+    return entry (move (f), true /* temporary */, compress_);
+  }
+
+  inline file_cache::entry file_cache::
+  create_existing (path f)
+  {
+    entry e (move (f), false /* temporary */, compress_);
+    e.init_existing ();
+    return e;
+  }
+
+  inline string file_cache::
+  compressed_extension (const char* e)
+  {
+    return compress_
+      ? (e != nullptr ? string (e) : string ()) + ".lz4"
+      : string ();
+  }
+
+  inline void file_cache::
+  init (bool compress)
+  {
+    compress_ = compress;
+  }
+
+  inline file_cache::
+  file_cache (bool compress)
+  {
+    init (compress);
+  }
+}