Backport new hash.h from git upstream to add support for VS2015

Signed-off-by: Michael Casadevall <mcasadevall@ubuntu.com>

depends/protobuf/google/protobuf/stubs/hash.h

@@ -1,6 +1,6 @@
 // Protocol Buffers - Google's data interchange format
 // Copyright 2008 Google Inc.  All rights reserved.
-// http://code.google.com/p/protobuf/
+// https://developers.google.com/protocol-buffers/
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
@@ -37,13 +37,134 @@
 
 #include <string.h>
 #include <google/protobuf/stubs/common.h>
-#include "config.h"
 
-#if defined(HAVE_HASH_MAP) && defined(HAVE_HASH_SET)
+#define GOOGLE_PROTOBUF_HAVE_HASH_MAP 1
-#include HASH_MAP_H
+#define GOOGLE_PROTOBUF_HAVE_HASH_SET 1
-#include HASH_SET_H
+
+// Android
+#if defined(__ANDROID__)
+# undef GOOGLE_PROTOBUF_HAVE_HASH_MAP
+# undef GOOGLE_PROTOBUF_HAVE_HASH_MAP
+
+// Use C++11 unordered_{map|set} if available.
+#elif ((_LIBCPP_STD_VER >= 11) || \
+      (((__cplusplus >= 201103L) || defined(__GXX_EXPERIMENTAL_CXX0X)) && \
+      (__GLIBCXX__ > 20090421)))
+# define GOOGLE_PROTOBUF_HAS_CXX11_HASH
+
+// For XCode >= 4.6:  the compiler is clang with libc++.
+// For earlier XCode version: the compiler is gcc-4.2.1 with libstdc++.
+// libc++ provides <unordered_map> and friends even in non C++11 mode,
+// and it does not provide the tr1 library. Therefore the following macro
+// checks against this special case.
+// Note that we should not test the __APPLE_CC__ version number or the
+// __clang__ macro, since the new compiler can still use -stdlib=libstdc++, in
+// which case <unordered_map> is not compilable without -std=c++11
+#elif defined(__APPLE_CC__)
+# if __GNUC__ >= 4
+#  define GOOGLE_PROTOBUF_HAS_TR1
 # else
-#define MISSING_HASH
+// Not tested for gcc < 4... These setting can compile under 4.2.1 though.
+#  define GOOGLE_PROTOBUF_HASH_NAMESPACE __gnu_cxx
+#  include <ext/hash_map>
+#  define GOOGLE_PROTOBUF_HASH_MAP_CLASS hash_map
+#  include <ext/hash_set>
+#  define GOOGLE_PROTOBUF_HASH_SET_CLASS hash_set
+# endif
+
+// Version checks for gcc.
+#elif defined(__GNUC__)
+// For GCC 4.x+, use tr1::unordered_map/set; otherwise, follow the
+// instructions from:
+// https://gcc.gnu.org/onlinedocs/libstdc++/manual/backwards.html
+# if __GNUC__ >= 4
+#  define GOOGLE_PROTOBUF_HAS_TR1
+# elif __GNUC__ >= 3
+#  include <backward/hash_map>
+#  define GOOGLE_PROTOBUF_HASH_MAP_CLASS hash_map
+#  include <backward/hash_set>
+#  define GOOGLE_PROTOBUF_HASH_SET_CLASS hash_set
+#  if __GNUC__ == 3 && __GNUC_MINOR__ == 0
+#   define GOOGLE_PROTOBUF_HASH_NAMESPACE std       // GCC 3.0
+#  else
+#   define GOOGLE_PROTOBUF_HASH_NAMESPACE __gnu_cxx // GCC 3.1 and later
+#  endif
+# else
+#  define GOOGLE_PROTOBUF_HASH_NAMESPACE
+#  include <hash_map>
+#  define GOOGLE_PROTOBUF_HASH_MAP_CLASS hash_map
+#  include <hash_set>
+#  define GOOGLE_PROTOBUF_HASH_SET_CLASS hash_set
+# endif
+
+// Version checks for MSC.
+// Apparently Microsoft decided to move hash_map *back* to the std namespace in
+// MSVC 2010:
+// http://blogs.msdn.com/vcblog/archive/2009/05/25/stl-breaking-changes-in-visual-studio-2010-beta-1.aspx
+// And.. they are moved back to stdext in MSVC 2013 (haven't checked 2012). That
+// said, use unordered_map for MSVC 2010 and beyond is our safest bet.
+#elif defined(_MSC_VER)
+# if _MSC_VER >= 1600  // Since Visual Studio 2010
+#  define GOOGLE_PROTOBUF_HAS_CXX11_HASH
+#  define GOOGLE_PROTOBUF_HASH_COMPARE std::hash_compare
+# elif _MSC_VER >= 1500  // Since Visual Studio 2008
+#  define GOOGLE_PROTOBUF_HASH_NAMESPACE stdext
+#  include <hash_map>
+#  define GOOGLE_PROTOBUF_HASH_MAP_CLASS hash_map
+#  include <hash_set>
+#  define GOOGLE_PROTOBUF_HASH_SET_CLASS hash_set
+#  define GOOGLE_PROTOBUF_HASH_COMPARE stdext::hash_compare
+#  define GOOGLE_PROTOBUF_CONTAINERS_NEED_HASH_COMPARE
+# elif _MSC_VER >= 1310
+#  define GOOGLE_PROTOBUF_HASH_NAMESPACE stdext
+#  include <hash_map>
+#  define GOOGLE_PROTOBUF_HASH_MAP_CLASS hash_map
+#  include <hash_set>
+#  define GOOGLE_PROTOBUF_HASH_SET_CLASS hash_set
+#  define GOOGLE_PROTOBUF_HASH_COMPARE stdext::hash_compare
+# else
+#  define GOOGLE_PROTOBUF_HASH_NAMESPACE std
+#  include <hash_map>
+#  define GOOGLE_PROTOBUF_HASH_MAP_CLASS hash_map
+#  include <hash_set>
+#  define GOOGLE_PROTOBUF_HASH_SET_CLASS hash_set
+#  define GOOGLE_PROTOBUF_HASH_COMPARE stdext::hash_compare
+# endif
+
+// **ADD NEW COMPILERS SUPPORT HERE.**
+// For other compilers, undefine the macro and fallback to use std::map, in
+// google/protobuf/stubs/hash.h
+#else
+# undef GOOGLE_PROTOBUF_HAVE_HASH_MAP
+# undef GOOGLE_PROTOBUF_HAVE_HASH_SET
+#endif
+
+#if defined(GOOGLE_PROTOBUF_HAS_CXX11_HASH)
+# define GOOGLE_PROTOBUF_HASH_NAMESPACE std
+# include <unordered_map>
+# define GOOGLE_PROTOBUF_HASH_MAP_CLASS unordered_map
+# include <unordered_set>
+# define GOOGLE_PROTOBUF_HASH_SET_CLASS unordered_set
+#elif defined(GOOGLE_PROTOBUF_HAS_TR1)
+# define GOOGLE_PROTOBUF_HASH_NAMESPACE std::tr1
+# include <tr1/unordered_map>
+# define GOOGLE_PROTOBUF_HASH_MAP_CLASS unordered_map
+# include <tr1/unordered_set>
+# define GOOGLE_PROTOBUF_HASH_SET_CLASS unordered_set
+#endif
+
+# define GOOGLE_PROTOBUF_HASH_NAMESPACE_DECLARATION_START \
+  namespace google {                                      \
+  namespace protobuf {
+# define GOOGLE_PROTOBUF_HASH_NAMESPACE_DECLARATION_END }}
+
+#undef GOOGLE_PROTOBUF_HAS_CXX11_HASH
+#undef GOOGLE_PROTOBUF_HAS_TR1
+
+#if defined(GOOGLE_PROTOBUF_HAVE_HASH_MAP) && \
+    defined(GOOGLE_PROTOBUF_HAVE_HASH_SET)
+#else
+#define GOOGLE_PROTOBUF_MISSING_HASH
 #include <map>
 #include <set>
 #endif
@@ -51,7 +172,8 @@
 namespace google {
   namespace protobuf {
 
-#ifdef MISSING_HASH
+#ifdef GOOGLE_PROTOBUF_MISSING_HASH
+#undef GOOGLE_PROTOBUF_MISSING_HASH
 
     // This system doesn't have hash_map or hash_set.  Emulate them using map and
     // set.
@@ -88,20 +210,33 @@ struct hash<const char*> {
 
     template <typename Key, typename Data,
       typename HashFcn = hash<Key>,
-          typename EqualKey = int >
+      typename EqualKey = std::equal_to<Key>,
-class hash_map : public std::map<Key, Data, HashFcn> {
+      typename Alloc = std::allocator< std::pair<const Key, Data> > >
+    class hash_map : public std::map<Key, Data, HashFcn, Alloc> {
+      typedef std::map<Key, Data, HashFcn, Alloc> BaseClass;
+
+    public:
+      hash_map(int a = 0, const HashFcn& b = HashFcn(),
+        const EqualKey& c = EqualKey(),
+        const Alloc& d = Alloc()) : BaseClass(b, d) {}
+
+      HashFcn hash_function() const { return HashFcn(); }
     };
 
     template <typename Key,
       typename HashFcn = hash<Key>,
-          typename EqualKey = int >
+      typename EqualKey = std::equal_to<Key> >
     class hash_set : public std::set<Key, HashFcn> {
+    public:
+      hash_set(int = 0) {}
+
+      HashFcn hash_function() const { return HashFcn(); }
     };
 
 #elif defined(_MSC_VER) && !defined(_STLPORT_VERSION)
 
     template <typename Key>
-struct hash : public HASH_NAMESPACE::hash_compare<Key> {
+    struct hash : public GOOGLE_PROTOBUF_HASH_COMPARE<Key> {
     };
 
     // MSVC's hash_compare<const char*> hashes based on the string contents but
@@ -115,27 +250,88 @@ class CstringLess {
 
     template <>
     struct hash<const char*>
-  : public HASH_NAMESPACE::hash_compare<const char*, CstringLess> {
+      : public GOOGLE_PROTOBUF_HASH_COMPARE<const char*, CstringLess> {};
+
+#ifdef GOOGLE_PROTOBUF_CONTAINERS_NEED_HASH_COMPARE
+
+    template <typename Key, typename HashFcn, typename EqualKey>
+    struct InternalHashCompare : public GOOGLE_PROTOBUF_HASH_COMPARE<Key> {
+      InternalHashCompare() {}
+      InternalHashCompare(HashFcn hashfcn, EqualKey equalkey)
+        : hashfcn_(hashfcn), equalkey_(equalkey) {}
+      size_t operator()(const Key& key) const { return hashfcn_(key); }
+      bool operator()(const Key& key1, const Key& key2) const {
+        return !equalkey_(key1, key2);
+      }
+      HashFcn hashfcn_;
+      EqualKey equalkey_;
     };
 
     template <typename Key, typename Data,
       typename HashFcn = hash<Key>,
-          typename EqualKey = int >
+      typename EqualKey = std::equal_to<Key>,
-class hash_map : public HASH_NAMESPACE::hash_map<
+      typename Alloc = std::allocator< std::pair<const Key, Data> > >
-    Key, Data, HashFcn> {
+    class hash_map
+      : public GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_MAP_CLASS<
+      Key, Data, InternalHashCompare<Key, HashFcn, EqualKey>, Alloc> {
+      typedef GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_MAP_CLASS<
+        Key, Data, InternalHashCompare<Key, HashFcn, EqualKey>, Alloc> BaseClass;
+
+    public:
+      hash_map(int a = 0, const HashFcn& b = HashFcn(),
+        const EqualKey& c = EqualKey(), const Alloc& d = Alloc())
+        : BaseClass(InternalHashCompare<Key, HashFcn, EqualKey>(b, c), d) {}
+
+      HashFcn hash_function() const { return HashFcn(); }
     };
 
-template <typename Key,
+    template <typename Key, typename HashFcn = hash<Key>,
+      typename EqualKey = std::equal_to<Key> >
+    class hash_set
+      : public GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_SET_CLASS<
+      Key, InternalHashCompare<Key, HashFcn, EqualKey> > {
+    public:
+      hash_set(int = 0) {}
+
+      HashFcn hash_function() const { return HashFcn(); }
+    };
+
+#else  // GOOGLE_PROTOBUF_CONTAINERS_NEED_HASH_COMPARE
+
+    template <typename Key, typename Data,
       typename HashFcn = hash<Key>,
-          typename EqualKey = int >
+      typename EqualKey = std::equal_to<Key>,
-class hash_set : public HASH_NAMESPACE::hash_set<
+      typename Alloc = std::allocator< std::pair<const Key, Data> > >
-    Key, HashFcn> {
+    class hash_map
+      : public GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_MAP_CLASS<
+      Key, Data, HashFcn, EqualKey, Alloc> {
+      typedef GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_MAP_CLASS<
+        Key, Data, HashFcn, EqualKey, Alloc> BaseClass;
+
+    public:
+      hash_map(int a = 0, const HashFcn& b = HashFcn(),
+        const EqualKey& c = EqualKey(),
+        const Alloc& d = Alloc()) : BaseClass(a, b, c, d) {}
+
+      HashFcn hash_function() const { return HashFcn(); }
     };
 
-#else
+    template <typename Key, typename HashFcn = hash<Key>,
+      typename EqualKey = std::equal_to<Key> >
+    class hash_set
+      : public GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_SET_CLASS<
+      Key, HashFcn, EqualKey> {
+    public:
+      hash_set(int = 0) {}
+
+      HashFcn hash_function() const { return HashFcn(); }
+    };
+#endif  // GOOGLE_PROTOBUF_CONTAINERS_NEED_HASH_COMPARE
+
+#else  // defined(_MSC_VER) && !defined(_STLPORT_VERSION)
 
     template <typename Key>
-struct hash : public HASH_NAMESPACE::hash<Key> {
+    struct hash : public GOOGLE_PROTOBUF_HASH_NAMESPACE::hash<Key> {
     };
 
     template <typename Key>
@@ -158,21 +354,43 @@ struct hash<const char*> {
       }
     };
 
+    template<>
+    struct hash<bool> {
+      size_t operator()(bool x) const {
+        return static_cast<size_t>(x);
+      }
+    };
+
     template <typename Key, typename Data,
       typename HashFcn = hash<Key>,
-          typename EqualKey = std::equal_to<Key> >
+      typename EqualKey = std::equal_to<Key>,
-class hash_map : public HASH_NAMESPACE::HASH_MAP_CLASS<
+      typename Alloc = std::allocator< std::pair<const Key, Data> > >
-    Key, Data, HashFcn, EqualKey> {
+    class hash_map
+      : public GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_MAP_CLASS<
+      Key, Data, HashFcn, EqualKey, Alloc> {
+      typedef GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_MAP_CLASS<
+        Key, Data, HashFcn, EqualKey, Alloc> BaseClass;
+
+    public:
+      hash_map(int a = 0, const HashFcn& b = HashFcn(),
+        const EqualKey& c = EqualKey(),
+        const Alloc& d = Alloc()) : BaseClass(a, b, c, d) {}
+
+      HashFcn hash_function() const { return HashFcn(); }
     };
 
-template <typename Key,
+    template <typename Key, typename HashFcn = hash<Key>,
-          typename HashFcn = hash<Key>,
       typename EqualKey = std::equal_to<Key> >
-class hash_set : public HASH_NAMESPACE::HASH_SET_CLASS<
+    class hash_set
+      : public GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_SET_CLASS<
       Key, HashFcn, EqualKey> {
+    public:
+      hash_set(int = 0) {}
+
+      HashFcn hash_function() const { return HashFcn(); }
     };
 
-#endif
+#endif  // !GOOGLE_PROTOBUF_MISSING_HASH
 
     template <>
     struct hash<string> {
@@ -182,7 +400,7 @@ struct hash<string> {
 
       static const size_t bucket_size = 4;
       static const size_t min_buckets = 8;
-  inline size_t operator()(const string& a, const string& b) const {
+      inline bool operator()(const string& a, const string& b) const {
         return a < b;
       }
     };
@@ -200,7 +418,7 @@ struct hash<pair<First, Second> > {
 
       static const size_t bucket_size = 4;
       static const size_t min_buckets = 8;
-  inline size_t operator()(const pair<First, Second>& a,
+      inline bool operator()(const pair<First, Second>& a,
         const pair<First, Second>& b) const {
         return a < b;
       }