From 04d9dc43f67b102c7727228326c05eb82d87e4f2 Mon Sep 17 00:00:00 2001
From: Abs62 <ottomann@yandex.ru>
Date: Thu, 17 Jan 2019 17:53:13 +0300
Subject: [PATCH] Fix some crashes (issue #1076)

---
 bgl.cc        |  9 ++++++---
 dictdfiles.cc |  7 +++++--
 dsl.cc        | 14 ++++++++++----
 epwing.cc     |  7 +++++--
 gls.cc        |  7 +++++--
 mdx.cc        | 16 +++++++++++-----
 sdict.cc      |  7 +++++--
 stardict.cc   |  3 +++
 utf8.cc       |  3 +++
 9 files changed, 53 insertions(+), 20 deletions(-)

diff --git a/bgl.cc b/bgl.cc
index decda949..09921bd8 100644
--- a/bgl.cc
+++ b/bgl.cc
@@ -289,11 +289,14 @@ namespace
 
     size_t len = idx.read< uint32_t >();
 
-    vector< char > nameBuf( len );
+    if( len )
+    {
+      vector< char > nameBuf( len );
 
-    idx.read( &nameBuf.front(), len );
+      idx.read( &nameBuf.front(), len );
 
-    dictionaryName = string( &nameBuf.front(), len );
+      dictionaryName = string( &nameBuf.front(), len );
+    }
 
     // Initialize the index
 
diff --git a/dictdfiles.cc b/dictdfiles.cc
index d503fc94..d633c23d 100644
--- a/dictdfiles.cc
+++ b/dictdfiles.cc
@@ -161,8 +161,11 @@ DictdDictionary::DictdDictionary( string const & id,
   idx.seek( sizeof( idxHeader ) );
 
   vector< char > dName( idx.read< uint32_t >() );
-  idx.read( &dName.front(), dName.size() );
-  dictionaryName = string( &dName.front(), dName.size() );
+  if( dName.size() > 0 )
+  {
+    idx.read( &dName.front(), dName.size() );
+    dictionaryName = string( &dName.front(), dName.size() );
+  }
 
   // Open the .dict file
 
diff --git a/dsl.cc b/dsl.cc
index aa1d1ac8..f9b1f9c8 100644
--- a/dsl.cc
+++ b/dsl.cc
@@ -310,12 +310,18 @@ DslDictionary::DslDictionary( string const & id,
   idx.seek( sizeof( idxHeader ) );
 
   vector< char > dName( idx.read< uint32_t >() );
-  idx.read( &dName.front(), dName.size() );
-  dictionaryName = string( &dName.front(), dName.size() );
+  if( dName.size() > 0 )
+  {
+    idx.read( &dName.front(), dName.size() );
+    dictionaryName = string( &dName.front(), dName.size() );
+  }
 
   vector< char > sName( idx.read< uint32_t >() );
-  idx.read( &sName.front(), sName.size() );
-  preferredSoundDictionary = string( &sName.front(), sName.size() );
+  if( sName.size() > 0 )
+  {
+    idx.read( &sName.front(), sName.size() );
+    preferredSoundDictionary = string( &sName.front(), sName.size() );
+  }
 
   // Everything else would be done in deferred init
 }
diff --git a/epwing.cc b/epwing.cc
index b3468948..76866cb9 100644
--- a/epwing.cc
+++ b/epwing.cc
@@ -204,8 +204,11 @@ EpwingDictionary::EpwingDictionary( string const & id,
 {
   vector< char > data( idxHeader.nameSize );
   idx.seek( sizeof( idxHeader ) );
-  idx.read( &data.front(), idxHeader.nameSize );
-  bookName = string( &data.front(), idxHeader.nameSize );
+  if( data.size() > 0 )
+  {
+    idx.read( &data.front(), idxHeader.nameSize );
+    bookName = string( &data.front(), idxHeader.nameSize );
+  }
 
   // Initialize eBook
 
diff --git a/gls.cc b/gls.cc
index b76a6de3..be067788 100644
--- a/gls.cc
+++ b/gls.cc
@@ -549,8 +549,11 @@ GlsDictionary::GlsDictionary( string const & id,
   idx.seek( sizeof( idxHeader ) );
 
   vector< char > dName( idx.read< uint32_t >() );
-  idx.read( &dName.front(), dName.size() );
-  dictionaryName = string( &dName.front(), dName.size() );
+  if( dName.size() > 0 )
+  {
+    idx.read( &dName.front(), dName.size() );
+    dictionaryName = string( &dName.front(), dName.size() );
+  }
 
   // Initialize the index
 
diff --git a/mdx.cc b/mdx.cc
index 9f6e94f1..b954374c 100644
--- a/mdx.cc
+++ b/mdx.cc
@@ -303,14 +303,20 @@ MdxDictionary::MdxDictionary( string const & id, string const & indexFile,
   idx.seek( sizeof( idxHeader ) );
   size_t len = idx.read< uint32_t >();
   vector< char > buf( len );
-  idx.read( &buf.front(), len );
-  dictionaryName = string( &buf.front(), len );
+  if( len > 0 )
+  {
+    idx.read( &buf.front(), len );
+    dictionaryName = string( &buf.front(), len );
+  }
 
   // then read the dictionary's encoding
   len = idx.read< uint32_t >();
-  buf.resize( len );
-  idx.read( &buf.front(), len );
-  encoding = string( &buf.front(), len );
+  if( len > 0 )
+  {
+    buf.resize( len );
+    idx.read( &buf.front(), len );
+    encoding = string( &buf.front(), len );
+  }
 
   dictFile.setFileName( QString::fromUtf8( dictionaryFiles[ 0 ].c_str() ) );
   dictFile.open( QIODevice::ReadOnly );
diff --git a/sdict.cc b/sdict.cc
index 312a522d..4bbda718 100644
--- a/sdict.cc
+++ b/sdict.cc
@@ -212,8 +212,11 @@ SdictDictionary::SdictDictionary( string const & id,
 
     idx.seek( sizeof( idxHeader ) );
     vector< char > dName( idx.read< uint32_t >() );
-    idx.read( &dName.front(), dName.size() );
-    dictionaryName = string( &dName.front(), dName.size() );
+    if( dName.size() > 0 )
+    {
+      idx.read( &dName.front(), dName.size() );
+      dictionaryName = string( &dName.front(), dName.size() );
+    }
 
     // Initialize the index
 
diff --git a/stardict.cc b/stardict.cc
index 18632375..9363d7dc 100644
--- a/stardict.cc
+++ b/stardict.cc
@@ -312,6 +312,9 @@ void StardictDictionary::loadIcon() throw()
 
 string StardictDictionary::loadString( size_t size )
 {
+  if( size == 0 )
+    return string();
+
   vector< char > data( size );
 
   idx.read( &data.front(), data.size() );
diff --git a/utf8.cc b/utf8.cc
index f8ea8f46..c7e516f4 100644
--- a/utf8.cc
+++ b/utf8.cc
@@ -133,6 +133,9 @@ long decode( char const * in_, size_t inSize, wchar * out_ )
 
 string encode( wstring const & in ) throw()
 {
+  if( in.size() == 0 )
+    return string();
+
   std::vector< char > buffer( in.size() * 4 );
 
   return string( &buffer.front(),