11 files changed, 213 insertions, 5 deletions
diff --git a/source/blender/blenlib/BLI_enumerable_thread_specific.hh b/source/blender/blenlib/BLI_enumerable_thread_specific.hh
new file mode 100644
index 00000000000..89be4cad848
--- /dev/null
+++ b/source/blender/blenlib/BLI_enumerable_thread_specific.hh
@@ -0,0 +1,73 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software  Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#pragma once
+
+#ifdef WITH_TBB
+#  include <tbb/enumerable_thread_specific.h>
+#endif
+
+#include <atomic>
+#include <mutex>
+
+#include "BLI_map.hh"
+#include "BLI_utility_mixins.hh"
+
+namespace blender {
+
+namespace enumerable_thread_specific_utils {
+inline std::atomic<int> next_id = 0;
+inline thread_local int thread_id = next_id.fetch_add(1, std::memory_order_relaxed);
+}  // namespace enumerable_thread_specific_utils
+
+/**
+ * This is mainly a wrapper for `tbb::enumerable_thread_specific`. The wrapper is needed because we
+ * want to be able to build without tbb.
+ *
+ * More features of the tbb version can be wrapped when they are used.
+ */
+template<typename T> class EnumerableThreadSpecific : NonCopyable, NonMovable {
+#ifdef WITH_TBB
+
+ private:
+  tbb::enumerable_thread_specific<T> values_;
+
+ public:
+  T &local()
+  {
+    return values_.local();
+  }
+
+#else /* WITH_TBB */
+
+ private:
+  std::mutex mutex_;
+  /* Maps thread ids to their corresponding values. The values are not embedded in the map, so that
+   * their addresses do not change when the map grows. */
+  Map<int, std::unique_ptr<T>> values_;
+
+ public:
+  T &local()
+  {
+    const int thread_id = enumerable_thread_specific_utils::thread_id;
+    std::lock_guard lock{mutex_};
+    return *values_.lookup_or_add_cb(thread_id, []() { return std::make_unique<T>(); });
+  }
+
+#endif /* WITH_TBB */
+};
+
+}  // namespace blender
diff --git a/source/blender/blenlib/BLI_fileops.h b/source/blender/blenlib/BLI_fileops.h
index df80e720363..bf18dd1070e 100644
--- a/source/blender/blenlib/BLI_fileops.h
+++ b/source/blender/blenlib/BLI_fileops.h
@@ -87,7 +87,7 @@ typedef enum eFileAttributes {
   FILE_ATTR_RESTRICTED = 1 << 6,      /* Protected by OS. */
   FILE_ATTR_TEMPORARY = 1 << 7,       /* Used for temporary storage. */
   FILE_ATTR_SPARSE_FILE = 1 << 8,     /* Sparse File. */
-  FILE_ATTR_OFFLINE = 1 << 9,         /* Data is not immediately available. */
+  FILE_ATTR_OFFLINE = 1 << 9,         /* Contents available after a short delay. */
   FILE_ATTR_ALIAS = 1 << 10,          /* Mac Alias or Windows LNK. File-based redirection. */
   FILE_ATTR_REPARSE_POINT = 1 << 11,  /* File has associated re-parse point. */
   FILE_ATTR_SYMLINK = 1 << 12,        /* Reference to another file. */
diff --git a/source/blender/blenlib/BLI_hash.hh b/source/blender/blenlib/BLI_hash.hh
index 4022c2baa1f..fbed321534c 100644
--- a/source/blender/blenlib/BLI_hash.hh
+++ b/source/blender/blenlib/BLI_hash.hh
@@ -85,9 +85,12 @@
 namespace blender {
 
 /**
- * If there is no other specialization of #DefaultHash for a given type, try to call `hash()` on
- * the value. If there is no such method, this will result in a compiler error. Usually that means
- * that you have to implement a hash function using one of three strategies listed above.
+ * If there is no other specialization of #DefaultHash for a given type, look for a hash function
+ * on the type itself. Implementing a `hash()` method on a type is often significantly easier than
+ * specializing #DefaultHash.
+ *
+ * To support heterogeneous lookup, a type can also implement a static `hash_as(const OtherType &)`
+ * function.
  *
  * In the case of an enum type, the default hash is just to cast the enum value to an integer.
  */
@@ -95,12 +98,25 @@ template<typename T> struct DefaultHash {
   uint64_t operator()(const T &value) const
   {
     if constexpr (std::is_enum_v<T>) {
+      /* For enums use the value as hash directly. */
       return (uint64_t)value;
     }
     else {
+      /* Try to call the `hash()` function on the value. */
+      /* If this results in a compiler error, no hash function for the type has been found. */
       return value.hash();
     }
   }
+
+  template<typename U> uint64_t operator()(const U &value) const
+  {
+    /* Try calling the static `T::hash_as(value)` function with the given value. The returned hash
+     * should be "compatible" with `T::hash()`. Usually that means that if `value` is converted to
+     * `T` its hash does not change. */
+    /* If this results in a compiler error, no hash function for the heterogeneous lookup has been
+     * found. */
+    return T::hash_as(value);
+  }
 };
 
 /**
diff --git a/source/blender/blenlib/BLI_linear_allocator.hh b/source/blender/blenlib/BLI_linear_allocator.hh
index bd883c1de16..87361d412cb 100644
--- a/source/blender/blenlib/BLI_linear_allocator.hh
+++ b/source/blender/blenlib/BLI_linear_allocator.hh
@@ -149,6 +149,21 @@ template<typename Allocator = GuardedAllocator> class LinearAllocator : NonCopya
   }
 
   /**
+   * Construct multiple instances of a type in an array. The constructor of is called with the
+   * given arguments. The caller is responsible for calling the destructor (and not `delete`) on
+   * the constructed elements.
+   */
+  template<typename T, typename... Args>
+  MutableSpan<T> construct_array(int64_t size, Args &&... args)
+  {
+    MutableSpan<T> array = this->allocate_array<T>(size);
+    for (const int64_t i : IndexRange(size)) {
+      new (&array[i]) T(std::forward<Args>(args)...);
+    }
+    return array;
+  }
+
+  /**
    * Copy the given array into a memory buffer provided by this allocator.
    */
   template<typename T> MutableSpan<T> construct_array_copy(Span<T> src)
diff --git a/source/blender/blenlib/BLI_map.hh b/source/blender/blenlib/BLI_map.hh
index 95afbfc2ec6..4d254960f34 100644
--- a/source/blender/blenlib/BLI_map.hh
+++ b/source/blender/blenlib/BLI_map.hh
@@ -605,6 +605,37 @@ class Map {
   }
 
   /**
+   * Returns the key that is stored in the set that compares equal to the given key. This invokes
+   * undefined behavior when the key is not in the map.
+   */
+  const Key &lookup_key(const Key &key) const
+  {
+    return this->lookup_key_as(key);
+  }
+  template<typename ForwardKey> const Key &lookup_key_as(const ForwardKey &key) const
+  {
+    const Slot &slot = this->lookup_slot(key, hash_(key));
+    return *slot.key();
+  }
+
+  /**
+   * Returns a pointer to the key that is stored in the map that compares equal to the given key.
+   * If the key is not in the map, null is returned.
+   */
+  const Key *lookup_key_ptr(const Key &key) const
+  {
+    return this->lookup_key_ptr_as(key);
+  }
+  template<typename ForwardKey> const Key *lookup_key_ptr_as(const ForwardKey &key) const
+  {
+    const Slot *slot = this->lookup_slot_ptr(key, hash_(key));
+    if (slot == nullptr) {
+      return nullptr;
+    }
+    return slot->key();
+  }
+
+  /**
    * Calls the provided callback for every key-value-pair in the map. The callback is expected
    * to take a `const Key &` as first and a `const Value &` as second parameter.
    */
diff --git a/source/blender/blenlib/BLI_vector_set.hh b/source/blender/blenlib/BLI_vector_set.hh
index 2f5d04aefa2..567e4fd8128 100644
--- a/source/blender/blenlib/BLI_vector_set.hh
+++ b/source/blender/blenlib/BLI_vector_set.hh
@@ -415,6 +415,38 @@ class VectorSet {
   }
 
   /**
+   * Returns the key that is stored in the vector set that compares equal to the given key. This
+   * invokes undefined behavior when the key is not in the set.
+   */
+  const Key &lookup_key(const Key &key) const
+  {
+    return this->lookup_key_as(key);
+  }
+  template<typename ForwardKey> const Key &lookup_key_as(const ForwardKey &key) const
+  {
+    const Key *key_ptr = this->lookup_key_ptr_as(key);
+    BLI_assert(key_ptr != nullptr);
+    return *key_ptr;
+  }
+
+  /**
+   * Returns a pointer to the key that is stored in the vector set that compares equal to the given
+   * key. If the key is not in the set, null is returned.
+   */
+  const Key *lookup_key_ptr(const Key &key) const
+  {
+    return this->lookup_key_ptr_as(key);
+  }
+  template<typename ForwardKey> const Key *lookup_key_ptr_as(const ForwardKey &key) const
+  {
+    const int64_t index = this->index_of_try__impl(key, hash_(key));
+    if (index >= 0) {
+      return keys_ + index;
+    }
+    return nullptr;
+  }
+
+  /**
    * Get a pointer to the beginning of the array containing all keys.
    */
   const Key *data() const
diff --git a/source/blender/blenlib/CMakeLists.txt b/source/blender/blenlib/CMakeLists.txt
index 06f937ce5ca..c8436b6b9cc 100644
--- a/source/blender/blenlib/CMakeLists.txt
+++ b/source/blender/blenlib/CMakeLists.txt
@@ -186,6 +186,7 @@ set(SRC
   BLI_edgehash.h
   BLI_endian_switch.h
   BLI_endian_switch_inline.h
+  BLI_enumerable_thread_specific.hh
   BLI_expr_pylike_eval.h
   BLI_fileops.h
   BLI_fileops_types.h
diff --git a/source/blender/blenlib/intern/storage.c b/source/blender/blenlib/intern/storage.c
index cb2634e6fda..5f823396ed9 100644
--- a/source/blender/blenlib/intern/storage.c
+++ b/source/blender/blenlib/intern/storage.c
@@ -266,7 +266,8 @@ eFileAttributes BLI_file_attributes(const char *path)
   if (attr & FILE_ATTRIBUTE_SPARSE_FILE) {
     ret |= FILE_ATTR_SPARSE_FILE;
   }
-  if (attr & FILE_ATTRIBUTE_OFFLINE) {
+  if (attr & FILE_ATTRIBUTE_OFFLINE || attr & FILE_ATTRIBUTE_RECALL_ON_OPEN ||
+      attr & FILE_ATTRIBUTE_RECALL_ON_DATA_ACCESS) {
     ret |= FILE_ATTR_OFFLINE;
   }
   if (attr & FILE_ATTRIBUTE_REPARSE_POINT) {
diff --git a/source/blender/blenlib/tests/BLI_linear_allocator_test.cc b/source/blender/blenlib/tests/BLI_linear_allocator_test.cc
index 977e5dba497..0e0145e592a 100644
--- a/source/blender/blenlib/tests/BLI_linear_allocator_test.cc
+++ b/source/blender/blenlib/tests/BLI_linear_allocator_test.cc
@@ -136,4 +136,17 @@ TEST(linear_allocator, ManyAllocations)
   }
 }
 
+TEST(linear_allocator, ConstructArray)
+{
+  LinearAllocator<> allocator;
+  MutableSpan<std::string> strings = allocator.construct_array<std::string>(4, "hello");
+  EXPECT_EQ(strings[0], "hello");
+  EXPECT_EQ(strings[1], "hello");
+  EXPECT_EQ(strings[2], "hello");
+  EXPECT_EQ(strings[3], "hello");
+  for (std::string &string : strings) {
+    string.~basic_string();
+  }
+}
+
 }  // namespace blender::tests
diff --git a/source/blender/blenlib/tests/BLI_map_test.cc b/source/blender/blenlib/tests/BLI_map_test.cc
index 18be456bd20..679a10e9ce0 100644
--- a/source/blender/blenlib/tests/BLI_map_test.cc
+++ b/source/blender/blenlib/tests/BLI_map_test.cc
@@ -640,6 +640,19 @@ TEST(map, RemoveDuringIteration)
   EXPECT_EQ(map.lookup(3), 3);
 }
 
+TEST(map, LookupKey)
+{
+  Map<std::string, int> map;
+  map.add("a", 0);
+  map.add("b", 1);
+  map.add("c", 2);
+  EXPECT_EQ(map.lookup_key("a"), "a");
+  EXPECT_EQ(map.lookup_key_as("c"), "c");
+  EXPECT_EQ(map.lookup_key_ptr_as("d"), nullptr);
+  EXPECT_EQ(map.lookup_key_ptr_as("b")->size(), 1);
+  EXPECT_EQ(map.lookup_key_ptr("a"), map.lookup_key_ptr_as("a"));
+}
+
 /**
  * Set this to 1 to activate the benchmark. It is disabled by default, because it prints a lot.
  */
diff --git a/source/blender/blenlib/tests/BLI_vector_set_test.cc b/source/blender/blenlib/tests/BLI_vector_set_test.cc
index c535ac57774..c4016ca75e1 100644
--- a/source/blender/blenlib/tests/BLI_vector_set_test.cc
+++ b/source/blender/blenlib/tests/BLI_vector_set_test.cc
@@ -258,4 +258,17 @@ TEST(vector_set, Clear)
   EXPECT_EQ(set.size(), 0);
 }
 
+TEST(vector_set, LookupKey)
+{
+  VectorSet<std::string> set;
+  set.add("a");
+  set.add("b");
+  set.add("c");
+  EXPECT_EQ(set.lookup_key("a"), "a");
+  EXPECT_EQ(set.lookup_key_as("c"), "c");
+  EXPECT_EQ(set.lookup_key_ptr_as("d"), nullptr);
+  EXPECT_EQ(set.lookup_key_ptr_as("b")->size(), 1);
+  EXPECT_EQ(set.lookup_key_ptr("a"), set.lookup_key_ptr_as("a"));
+}
+
 }  // namespace blender::tests