Merge pull request #12065 from vjpai/moreslices

Add Slice constructors to match all grpc_slice cases

include/grpc++/support/slice.h

@@ -67,6 +67,20 @@ class Slice final {
     return *this;
   }
 
+  /// Create a slice pointing at some data. Calls malloc to allocate a refcount
+  /// for the object, and arranges that destroy will be called with the
+  /// user data pointer passed in at destruction. Can be the same as buf or
+  /// different (e.g., if data is part of a larger structure that must be
+  /// destroyed when the data is no longer needed)
+  Slice(void* buf, size_t len, void (*destroy)(void*), void* user_data);
+
+  /// Specialization of above for common case where buf == user_data
+  Slice(void* buf, size_t len, void (*destroy)(void*))
+      : Slice(buf, len, destroy, buf) {}
+
+  /// Similar to the above but has a destroy that also takes slice length
+  Slice(void* buf, size_t len, void (*destroy)(void*, size_t));
+
   /// Byte size.
   size_t size() const { return GRPC_SLICE_LENGTH(slice_); }
 

src/cpp/util/slice_cc.cc

@@ -17,6 +17,7 @@
  */
 
 #include <grpc++/support/slice.h>
+#include <grpc/slice.h>
 
 namespace grpc {
 
@@ -43,4 +44,10 @@ Slice::Slice(const void* buf, size_t len, StaticSlice)
 
 Slice::Slice(const Slice& other) : slice_(grpc_slice_ref(other.slice_)) {}
 
+Slice::Slice(void* buf, size_t len, void (*destroy)(void*), void* user_data)
+    : slice_(grpc_slice_new_with_user_data(buf, len, destroy, user_data)) {}
+
+Slice::Slice(void* buf, size_t len, void (*destroy)(void*, size_t))
+    : slice_(grpc_slice_new_with_len(buf, len, destroy)) {}
+
 }  // namespace grpc

test/cpp/util/slice_test.cc

@@ -63,6 +63,42 @@ TEST_F(SliceTest, StaticBuf) {
   CheckSlice(spp, kContent);
 }
 
+TEST_F(SliceTest, SliceNew) {
+  char* x = new char[strlen(kContent) + 1];
+  strcpy(x, kContent);
+  Slice spp(x, strlen(x), [](void* p) { delete[] reinterpret_cast<char*>(p); });
+  CheckSlice(spp, kContent);
+}
+
+TEST_F(SliceTest, SliceNewDoNothing) {
+  Slice spp(const_cast<char*>(kContent), strlen(kContent), [](void* p) {});
+  CheckSlice(spp, kContent);
+}
+
+TEST_F(SliceTest, SliceNewWithUserData) {
+  struct stest {
+    char* x;
+    int y;
+  };
+  auto* t = new stest;
+  t->x = new char[strlen(kContent) + 1];
+  strcpy(t->x, kContent);
+  Slice spp(t->x, strlen(t->x),
+            [](void* p) {
+              auto* t = reinterpret_cast<stest*>(p);
+              delete[] t->x;
+              delete t;
+            },
+            t);
+  CheckSlice(spp, kContent);
+}
+
+TEST_F(SliceTest, SliceNewLen) {
+  Slice spp(const_cast<char*>(kContent), strlen(kContent),
+            [](void* p, size_t l) { EXPECT_EQ(l, strlen(kContent)); });
+  CheckSlice(spp, kContent);
+}
+
 TEST_F(SliceTest, Steal) {
   grpc_slice s = grpc_slice_from_copied_string(kContent);
   Slice spp(s, Slice::STEAL_REF);