iostream: Remove write()-s of packet/scattered_message from new API level

Since we're introducing the new level anyway, it's good to instantly
switch all users into using the write(span) for zero-copy IO. The
write(temporary_buffer) is kept for convenience.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>

Author: xemul

apps/memcached/memcache.cc

@@ -917,7 +917,8 @@ class ascii_protocol {
                 scattered_message<char> msg;
                 this_type::append_item<WithVersion>(msg, std::move(item));
                 msg.append_static(msg_end);
-                return out.write(std::move(msg));
+                std::vector<temporary_buffer<char>> bufs = std::move(msg).release().release();
+                return out.write(std::span<temporary_buffer<char>>(bufs));
             });
         } else {
             _items.clear();
@@ -931,7 +932,8 @@ class ascii_protocol {
                     append_item<WithVersion>(msg, std::move(item));
                 }
                 msg.append_static(msg_end);
-                return out.write(std::move(msg));
+                std::vector<temporary_buffer<char>> bufs = std::move(msg).release().release();
+                return out.write(std::span<temporary_buffer<char>>(bufs));
             });
         }
     }

include/seastar/core/iostream-impl.hh

@@ -145,6 +145,7 @@ future<> output_stream<CharType>::write(temporary_buffer<CharType> p) noexcept {
   }
 }
 
+#if SEASTAR_API_LEVEL < 9
 template<typename CharType>
 future<> output_stream<CharType>::write(net::packet p) noexcept {
     try {
@@ -159,6 +160,7 @@ template<typename CharType>
 future<> output_stream<CharType>::write(scattered_message<CharType> msg) noexcept {
     return write(std::move(msg).release());
 }
+#endif
 
 template <typename CharType>
 future<temporary_buffer<CharType>>

include/seastar/core/iostream.hh

@@ -512,10 +512,13 @@ public:
     /// Writes the given string into the buffer
     future<> write(const std::basic_string<char_type>& s) noexcept;
 
+#if SEASTAR_API_LEVEL < 9
     /// Appends the packet as zero-copy buffer
     future<> write(net::packet p) noexcept;
     /// Appends the scattered message as zero-copy buffer
     future<> write(scattered_message<char_type> msg) noexcept;
+#endif
+
     /// Appends the temporary buffer as zero-copy buffer
     future<> write(temporary_buffer<char_type>) noexcept;
     /// Appends a bunch of buffers as zero-copy