From e271ad9c781967b01c3f94a93216e099cfd73b36 Mon Sep 17 00:00:00 2001
From: "Adam C. Emerson" <aemerson@redhat.com>
Date: Mon, 29 Jan 2018 23:23:14 -0500
Subject: [PATCH] buffer: Append from std::string_view

Now that we have std::string_view.

Signed-off-by: Adam C. Emerson <aemerson@redhat.com>
---
 src/include/buffer.h                    | 25 ++++++++++++++++++++++++-
 src/test/compressor/test_compression.cc |  4 ++--
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/src/include/buffer.h b/src/include/buffer.h
index 0d4bc0adf5f62..b59f271135762 100644
--- a/src/include/buffer.h
+++ b/src/include/buffer.h
@@ -43,6 +43,10 @@
 #include <list>
 #include <vector>
 #include <string>
+#if __cplusplus >= 201703L
+#include <string_view>
+#endif // __cplusplus >= 201703L
+
 #include <exception>
 #include <type_traits>
 
@@ -334,6 +338,11 @@ namespace buffer CEPH_BUFFER_API {
 
     unsigned append(char c);
     unsigned append(const char *p, unsigned l);
+#if __cplusplus >= 201703L
+    inline unsigned append(std::string_view s) {
+      return append(s.data(), s.length());
+    }
+#endif // __cplusplus >= 201703L
     void copy_in(unsigned o, unsigned l, const char *src);
     void copy_in(unsigned o, unsigned l, const char *src, bool crc_reset);
     void zero();
@@ -844,9 +853,23 @@ namespace buffer CEPH_BUFFER_API {
 
     void append(char c);
     void append(const char *data, unsigned len);
-    void append(const std::string& s) {
+    void append(std::string s) {
+      append(s.data(), s.length());
+    }
+#if __cplusplus >= 201703L
+    // To forcibly disambiguate between string and string_view in the
+    // case of arrays
+    template<std::size_t N>
+    void append(const char (&s)[N]) {
+      append(s, N);
+    }
+    void append(const char* s) {
+      append(s, strlen(s));
+    }
+    void append(std::string_view s) {
       append(s.data(), s.length());
     }
+#endif // __cplusplus >= 201703L
     void append(const ptr& bp);
     void append(ptr&& bp);
     void append(const ptr& bp, unsigned off, unsigned len);
diff --git a/src/test/compressor/test_compression.cc b/src/test/compressor/test_compression.cc
index a799a93ddd0e7..0802603124c01 100644
--- a/src/test/compressor/test_compression.cc
+++ b/src/test/compressor/test_compression.cc
@@ -366,7 +366,7 @@ TEST(ZlibCompressor, zlib_isal_compatibility)
   res = zlib->decompress(out, after);
   EXPECT_EQ(res, 0);
   bufferlist exp;
-  exp.append(test);
+  exp.append(static_cast<char*>(test));
   EXPECT_TRUE(exp.contents_equal(after));
   after.clear();
   out.clear();
@@ -376,7 +376,7 @@ TEST(ZlibCompressor, zlib_isal_compatibility)
   EXPECT_EQ(res, 0);
   res = isal->decompress(out, after);
   EXPECT_EQ(res, 0);
-  exp.append(test);
+  exp.append(static_cast<char*>(test));
   EXPECT_TRUE(exp.contents_equal(after));
 }
 #endif
-- 
2.39.5