From 1b57e247b8d1a7a41a8ee45d6d524c71edd63a81 Mon Sep 17 00:00:00 2001
From: Boris Kolpackov <boris@codesynthesis.com>
Date: Fri, 26 May 2017 17:20:30 +0200
Subject: Optimize char_scanner if used with ifdstream

---
 libbutl/char-scanner.ixx | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

(limited to 'libbutl/char-scanner.ixx')

diff --git a/libbutl/char-scanner.ixx b/libbutl/char-scanner.ixx
index 2d96207..0e00dfd 100644
--- a/libbutl/char-scanner.ixx
+++ b/libbutl/char-scanner.ixx
@@ -29,4 +29,35 @@ namespace butl
     unget_ = true;
     ungetc_ = c;
   }
+
+  inline auto char_scanner::
+  peek_ () -> int_type
+  {
+    if (gptr_ != egptr_)
+      return *gptr_;
+
+    int_type r (is_.peek ());
+
+    // Update buffer pointers for the next chunk.
+    //
+    if (buf_ != nullptr)
+    {
+      gptr_ = buf_->gptr ();
+      egptr_ = buf_->egptr ();
+    }
+
+    return r;
+  }
+
+  inline void char_scanner::
+  get_ ()
+  {
+    if (gptr_ != egptr_)
+    {
+      buf_->gbump (1);
+      ++gptr_;
+    }
+    else
+      is_.get (); // About as fast as ignore() and way faster than tellg().
+  }
 }
-- 
cgit v1.1