From: Marco Costalba <mcostalba@gmail.com>
Date: Sat, 4 Dec 2010 20:19:22 +0000 (+0100)
Subject: Fix a crash due to a broken Book::open()
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=97a6e1559e78dd31a5ecec9f3b35181f82942823;hp=8a858aea34940920f9cd44e3006a632077e9f6ab

Fix a crash due to a broken Book::open()

Bug introduced in 9dcc2aad98b9703

We can be asked to open a non-exsistent file,
in this case we should gracefully handle the
case and silently return instead of exiting.

Bug discovered and bisected down by Joona.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
---

diff --git a/src/book.cpp b/src/book.cpp
index 95ccd690..9528e47c 100644
--- a/src/book.cpp
+++ b/src/book.cpp
@@ -365,18 +365,20 @@ void Book::open(const string& fName) {
   fileName = fName;
   ifstream::open(fileName.c_str(), ifstream::in | ifstream::binary);
 
-  if (is_open())
-  {
-      // Get the book size in number of entries
-      seekg(0, ios::end);
-      bookSize = long(tellg()) / EntrySize;
-      seekg(0, ios::beg);
+  // Silently return when asked to open a non-exsistent file
+  if (!is_open())
+      return;
+
+  // Get the book size in number of entries
+  seekg(0, ios::end);
+  bookSize = long(tellg()) / EntrySize;
+  seekg(0, ios::beg);
 
-      if (good())
-          return;
+  if (!good())
+  {
+      cerr << "Failed to open book file " << fileName << endl;
+      exit(EXIT_FAILURE);
   }
-  cerr << "Failed to open book file " << fileName << endl;
-  exit(EXIT_FAILURE);
 }