epee: better network buffer data structure

avoids pointless allocs and memcpy

6 files changed, 97 insertions, 40 deletions

diff --git a/contrib/epee/include/net/buffer.h b/contrib/epee/include/net/buffer.h
new file mode 100644
index 000000000..56c67f6bf
--- /dev/null
+++ b/contrib/epee/include/net/buffer.h
@@ -0,0 +1,62 @@
+// Copyright (c) 2018, The Monero Project
+// 
+// All rights reserved.
+// 
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+// 
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+// 
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+// 
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+// 
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#pragma once
+
+#include <vector>
+#include "misc_log_ex.h"
+#include "span.h"
+
+#undef MONERO_DEFAULT_LOG_CATEGORY
+#define MONERO_DEFAULT_LOG_CATEGORY "net.buffer"
+
+//#define NET_BUFFER_LOG(x) MDEBUG(x)
+#define NET_BUFFER_LOG(x) ((void)0)
+
+namespace epee
+{
+namespace net_utils
+{
+class buffer
+{
+public:
+  buffer(size_t reserve = 0): offset(0) { storage.reserve(reserve); }
+
+  void append(const void *data, size_t sz);
+  void erase(size_t sz) { NET_BUFFER_LOG("erasing " << sz << "/" << size()); CHECK_AND_ASSERT_THROW_MES(offset + sz <= storage.size(), "erase: sz too large"); offset += sz; if (offset == storage.size()) { storage.resize(0); offset = 0; } }
+  epee::span<const uint8_t> span(size_t sz) const { CHECK_AND_ASSERT_THROW_MES(sz <= size(), "span is too large"); return epee::span<const uint8_t>(storage.data() + offset, sz); }
+  // carve must keep the data in scope till next call, other API calls (such as append, erase) can invalidate the carved buffer
+  epee::span<const uint8_t> carve(size_t sz) { CHECK_AND_ASSERT_THROW_MES(sz <= size(), "span is too large"); offset += sz; return epee::span<const uint8_t>(storage.data() + offset - sz, sz); }
+  size_t size() const { return storage.size() - offset; }
+
+private:
+  std::vector<uint8_t> storage;
+  size_t offset;
+};
+}
+}
diff --git a/contrib/epee/include/net/http_server_handlers_map2.h b/contrib/epee/include/net/http_server_handlers_map2.h
index 997c801d1..64d035df9 100644
--- a/contrib/epee/include/net/http_server_handlers_map2.h
+++ b/contrib/epee/include/net/http_server_handlers_map2.h
@@ -92,7 +92,7 @@
       handled = true; \
       uint64_t ticks = misc_utils::get_tick_count(); \
       boost::value_initialized<command_type::request> req; \
-      bool parse_res = epee::serialization::load_t_from_binary(static_cast<command_type::request&>(req), query_info.m_body); \
+      bool parse_res = epee::serialization::load_t_from_binary(static_cast<command_type::request&>(req), epee::strspan<uint8_t>(query_info.m_body)); \
       CHECK_AND_ASSERT_MES(parse_res, false, "Failed to parse bin body data, body size=" << query_info.m_body.size()); \
       uint64_t ticks1 = misc_utils::get_tick_count(); \
       boost::value_initialized<command_type::response> resp;\
diff --git a/contrib/epee/include/net/levin_base.h b/contrib/epee/include/net/levin_base.h
index 7d060f5ef..a88a1eb49 100644
--- a/contrib/epee/include/net/levin_base.h
+++ b/contrib/epee/include/net/levin_base.h
@@ -80,8 +80,8 @@ namespace levin
   template<class t_connection_context = net_utils::connection_context_base>
   struct levin_commands_handler
   {
-    virtual int invoke(int command, const std::string& in_buff, std::string& buff_out, t_connection_context& context)=0;
-    virtual int notify(int command, const std::string& in_buff, t_connection_context& context)=0;
+    virtual int invoke(int command, const epee::span<const uint8_t> in_buff, std::string& buff_out, t_connection_context& context)=0;
+    virtual int notify(int command, const epee::span<const uint8_t> in_buff, t_connection_context& context)=0;
     virtual void callback(t_connection_context& context){};
 
     virtual void on_connection_new(t_connection_context& context){};
diff --git a/contrib/epee/include/net/levin_client.h b/contrib/epee/include/net/levin_client.h
index 335f6ba02..76d528234 100644
--- a/contrib/epee/include/net/levin_client.h
+++ b/contrib/epee/include/net/levin_client.h
@@ -57,7 +57,7 @@ namespace levin
 		bool is_connected();
 		bool disconnect();
 
-		virtual int invoke(int command, const std::string& in_buff, std::string& buff_out);
+		virtual int invoke(int command, const epee::span<const uint8_t> in_buff, std::string& buff_out);
 		virtual int notify(int command, const std::string& in_buff);
 
 	protected: 
@@ -72,7 +72,7 @@ namespace levin
   {
   public:
 
-    int invoke(int command, const std::string& in_buff, std::string& buff_out);
+    int invoke(int command, const epee::span<const uint8_t> in_buff, std::string& buff_out);
     int notify(int command, const std::string& in_buff);
   };
 
diff --git a/contrib/epee/include/net/levin_client.inl b/contrib/epee/include/net/levin_client.inl
index a580e81fd..2f048b027 100644
--- a/contrib/epee/include/net/levin_client.inl
+++ b/contrib/epee/include/net/levin_client.inl
@@ -74,7 +74,7 @@ levin_client_impl::~levin_client_impl()
 }
 //------------------------------------------------------------------------------
 inline
-int levin_client_impl::invoke(int command, const std::string& in_buff, std::string& buff_out)
+int levin_client_impl::invoke(int command, const epee::span<const uint8_t> in_buff, std::string& buff_out)
 {
 	if(!is_connected())
 		return -1;
@@ -133,7 +133,7 @@ int levin_client_impl::notify(int command, const std::string& in_buff)
 //------------------------------------------------------------------------------
 //------------------------------------------------------------------------------
 inline
-  int levin_client_impl2::invoke(int command, const std::string& in_buff, std::string& buff_out)
+  int levin_client_impl2::invoke(int command, epee::span<const uint8_t>string& in_buff, std::string& buff_out)
 {
   if(!is_connected())
     return -1;
diff --git a/contrib/epee/include/net/levin_protocol_handler_async.h b/contrib/epee/include/net/levin_protocol_handler_async.h
index 6b1528caf..264b7aec4 100644
--- a/contrib/epee/include/net/levin_protocol_handler_async.h
+++ b/contrib/epee/include/net/levin_protocol_handler_async.h
@@ -34,6 +34,7 @@
 #include <atomic>
 
 #include "levin_base.h"
+#include "buffer.h"
 #include "misc_language.h"
 #include "syncobj.h"
 #include "misc_os_dependent.h"
@@ -85,11 +86,11 @@ public:
   uint64_t m_max_packet_size; 
   uint64_t m_invoke_timeout;
 
-  int invoke(int command, const std::string& in_buff, std::string& buff_out, boost::uuids::uuid connection_id);
+  int invoke(int command, const epee::span<const uint8_t> in_buff, std::string& buff_out, boost::uuids::uuid connection_id);
   template<class callback_t>
-  int invoke_async(int command, const std::string& in_buff, boost::uuids::uuid connection_id, const callback_t &cb, size_t timeout = LEVIN_DEFAULT_TIMEOUT_PRECONFIGURED);
+  int invoke_async(int command, const epee::span<const uint8_t> in_buff, boost::uuids::uuid connection_id, const callback_t &cb, size_t timeout = LEVIN_DEFAULT_TIMEOUT_PRECONFIGURED);
 
-  int notify(int command, const std::string& in_buff, boost::uuids::uuid connection_id);
+  int notify(int command, const epee::span<const uint8_t> in_buff, boost::uuids::uuid connection_id);
   bool close(boost::uuids::uuid connection_id);
   bool update_connection_context(const t_connection_context& contxt);
   bool request_callback(boost::uuids::uuid connection_id);
@@ -143,7 +144,7 @@ public:
   config_type& m_config;
   t_connection_context& m_connection_context;
 
-  std::string m_cache_in_buffer;
+  net_utils::buffer m_cache_in_buffer;
   stream_state m_state;
 
   int32_t m_oponent_protocol_ver;
@@ -151,7 +152,7 @@ public:
 
   struct invoke_response_handler_base
   {
-    virtual bool handle(int res, const std::string& buff, connection_context& context)=0;
+    virtual bool handle(int res, const epee::span<const uint8_t> buff, connection_context& context)=0;
     virtual bool is_timer_started() const=0;
     virtual void cancel()=0;
     virtual bool cancel_timer()=0;
@@ -173,7 +174,7 @@ public:
           if(ec == boost::asio::error::operation_aborted)
             return;
           MINFO(con.get_context_ref() << "Timeout on invoke operation happened, command: " << command << " timeout: " << timeout);
-          std::string fake;
+          epee::span<const uint8_t> fake;
           cb(LEVIN_ERROR_CONNECTION_TIMEDOUT, fake, con.get_context_ref());
           con.close();
           con.finish_outer_call();
@@ -191,7 +192,7 @@ public:
     bool m_timer_cancelled;
     uint64_t m_timeout;
     int m_command;
-    virtual bool handle(int res, const std::string& buff, typename async_protocol_handler::connection_context& context)
+    virtual bool handle(int res, const epee::span<const uint8_t> buff, typename async_protocol_handler::connection_context& context)
     {
       if(!cancel_timer())
         return false;
@@ -207,7 +208,7 @@ public:
     {
       if(cancel_timer())
       {
-        std::string fake;
+        epee::span<const uint8_t> fake;
         m_cb(LEVIN_ERROR_CONNECTION_DESTROYED, fake, m_con.get_context_ref());
         m_con.finish_outer_call();
       }
@@ -237,7 +238,7 @@ public:
           if(ec == boost::asio::error::operation_aborted)
             return;
           MINFO(con.get_context_ref() << "Timeout on invoke operation happened, command: " << command << " timeout: " << timeout);
-          std::string fake;
+          epee::span<const uint8_t> fake;
           cb(LEVIN_ERROR_CONNECTION_TIMEDOUT, fake, con.get_context_ref());
           con.close();
           con.finish_outer_call();
@@ -265,6 +266,7 @@ public:
             m_pservice_endpoint(psnd_hndlr), 
             m_config(config), 
             m_connection_context(conn_context), 
+            m_cache_in_buffer(256 * 1024),
             m_state(stream_state_head)
   {
     m_close_called = 0;
@@ -405,14 +407,7 @@ public:
           break;
         }
         {
-          std::string buff_to_invoke;
-          if(m_cache_in_buffer.size()  == m_current_head.m_cb)
-            buff_to_invoke.swap(m_cache_in_buffer);
-          else
-          {
-            buff_to_invoke.assign(m_cache_in_buffer, 0, (std::string::size_type)m_current_head.m_cb);
-            m_cache_in_buffer.erase(0, (std::string::size_type)m_current_head.m_cb);
-          }
+          epee::span<const uint8_t> buff_to_invoke = m_cache_in_buffer.carve((std::string::size_type)m_current_head.m_cb);
 
           bool is_response = (m_oponent_protocol_ver == LEVIN_PROTOCOL_VER_1 && m_current_head.m_flags&LEVIN_PACKET_RESPONSE);
 
@@ -449,8 +444,8 @@ public:
               }else
               {
                 CRITICAL_REGION_BEGIN(m_local_inv_buff_lock);
-                buff_to_invoke.swap(m_local_inv_buff);
-                buff_to_invoke.clear();
+                m_local_inv_buff = std::string((const char*)buff_to_invoke.data(), buff_to_invoke.size());
+                buff_to_invoke = epee::span<const uint8_t>((const uint8_t*)NULL, 0);
                 m_invoke_result_code = m_current_head.m_return_code;
                 CRITICAL_REGION_END();
                 boost::interprocess::ipcdetail::atomic_write32(&m_invoke_buf_ready, 1);
@@ -503,7 +498,7 @@ public:
         {
           if(m_cache_in_buffer.size() < sizeof(bucket_head2))
           {
-            if(m_cache_in_buffer.size() >= sizeof(uint64_t) && *((uint64_t*)m_cache_in_buffer.data()) != SWAP64LE(LEVIN_SIGNATURE))
+            if(m_cache_in_buffer.size() >= sizeof(uint64_t) && *((uint64_t*)m_cache_in_buffer.span(8).data()) != SWAP64LE(LEVIN_SIGNATURE))
             {
               MWARNING(m_connection_context << "Signature mismatch, connection will be closed");
               return false;
@@ -513,9 +508,9 @@ public:
           }
 
 #if BYTE_ORDER == LITTLE_ENDIAN
-          bucket_head2& phead = *(bucket_head2*)m_cache_in_buffer.data();
+          bucket_head2& phead = *(bucket_head2*)m_cache_in_buffer.span(sizeof(bucket_head2)).data();
 #else
-          bucket_head2 phead = *(bucket_head2*)m_cache_in_buffer.data();
+          bucket_head2 phead = *(bucket_head2*)m_cache_in_buffer.span(sizeof(bucket_head2)).data();
           phead.m_signature = SWAP64LE(phead.m_signature);
           phead.m_cb = SWAP64LE(phead.m_cb);
           phead.m_command = SWAP32LE(phead.m_command);
@@ -530,7 +525,7 @@ public:
           }
           m_current_head = phead;
 
-          m_cache_in_buffer.erase(0, sizeof(bucket_head2));
+          m_cache_in_buffer.erase(sizeof(bucket_head2));
           m_state = stream_state_body;
           m_oponent_protocol_ver = m_current_head.m_protocol_version;
           if(m_current_head.m_cb > m_config.m_max_packet_size)
@@ -562,7 +557,7 @@ public:
   }
 
   template<class callback_t>
-  bool async_invoke(int command, const std::string& in_buff, const callback_t &cb, size_t timeout = LEVIN_DEFAULT_TIMEOUT_PRECONFIGURED)
+  bool async_invoke(int command, const epee::span<const uint8_t> in_buff, const callback_t &cb, size_t timeout = LEVIN_DEFAULT_TIMEOUT_PRECONFIGURED)
   {
     misc_utils::auto_scope_leave_caller scope_exit_handler = misc_utils::create_scope_leave_handler(
       boost::bind(&async_protocol_handler::finish_outer_call, this));
@@ -606,7 +601,7 @@ public:
         break;
       }
 
-      if(!m_pservice_endpoint->do_send(in_buff.data(), (int)in_buff.size()))
+      if(!m_pservice_endpoint->do_send(in_buff.data(), in_buff.size()))
       {
         LOG_ERROR_CC(m_connection_context, "Failed to do_send");
         err_code = LEVIN_ERROR_CONNECTION;
@@ -623,7 +618,7 @@ public:
 
     if (LEVIN_OK != err_code)
     {
-      std::string stub_buff;
+      epee::span<const uint8_t> stub_buff{(const uint8_t*)"", 0};
       // Never call callback inside critical section, that can cause deadlock
       cb(err_code, stub_buff, m_connection_context);
       return false;
@@ -632,7 +627,7 @@ public:
     return true;
   }
 
-  int invoke(int command, const std::string& in_buff, std::string& buff_out)
+  int invoke(int command, const epee::span<const uint8_t> in_buff, std::string& buff_out)
   {
     misc_utils::auto_scope_leave_caller scope_exit_handler = misc_utils::create_scope_leave_handler(
                                       boost::bind(&async_protocol_handler::finish_outer_call, this));
@@ -662,7 +657,7 @@ public:
       return LEVIN_ERROR_CONNECTION;
     }
 
-    if(!m_pservice_endpoint->do_send(in_buff.data(), (int)in_buff.size()))
+    if(!m_pservice_endpoint->do_send(in_buff.data(), in_buff.size()))
     {
       LOG_ERROR_CC(m_connection_context, "Failed to do_send");
       return LEVIN_ERROR_CONNECTION;
@@ -706,7 +701,7 @@ public:
     return m_invoke_result_code;
   }
 
-  int notify(int command, const std::string& in_buff)
+  int notify(int command, const epee::span<const uint8_t> in_buff)
   {
     misc_utils::auto_scope_leave_caller scope_exit_handler = misc_utils::create_scope_leave_handler(
                           boost::bind(&async_protocol_handler::finish_outer_call, this));
@@ -734,7 +729,7 @@ public:
       return -1;
     }
 
-    if(!m_pservice_endpoint->do_send(in_buff.data(), (int)in_buff.size()))
+    if(!m_pservice_endpoint->do_send(in_buff.data(), in_buff.size()))
     {
       LOG_ERROR_CC(m_connection_context, "Failed to do_send()");
       return -1;
@@ -839,7 +834,7 @@ int async_protocol_handler_config<t_connection_context>::find_and_lock_connectio
 }
 //------------------------------------------------------------------------------------------
 template<class t_connection_context>
-int async_protocol_handler_config<t_connection_context>::invoke(int command, const std::string& in_buff, std::string& buff_out, boost::uuids::uuid connection_id)
+int async_protocol_handler_config<t_connection_context>::invoke(int command, const epee::span<const uint8_t> in_buff, std::string& buff_out, boost::uuids::uuid connection_id)
 {
   async_protocol_handler<t_connection_context>* aph;
   int r = find_and_lock_connection(connection_id, aph);
@@ -847,7 +842,7 @@ int async_protocol_handler_config<t_connection_context>::invoke(int command, con
 }
 //------------------------------------------------------------------------------------------
 template<class t_connection_context> template<class callback_t>
-int async_protocol_handler_config<t_connection_context>::invoke_async(int command, const std::string& in_buff, boost::uuids::uuid connection_id, const callback_t &cb, size_t timeout)
+int async_protocol_handler_config<t_connection_context>::invoke_async(int command, const epee::span<const uint8_t> in_buff, boost::uuids::uuid connection_id, const callback_t &cb, size_t timeout)
 {
   async_protocol_handler<t_connection_context>* aph;
   int r = find_and_lock_connection(connection_id, aph);
@@ -896,7 +891,7 @@ void async_protocol_handler_config<t_connection_context>::set_handler(levin_comm
 }
 //------------------------------------------------------------------------------------------
 template<class t_connection_context>
-int async_protocol_handler_config<t_connection_context>::notify(int command, const std::string& in_buff, boost::uuids::uuid connection_id)
+int async_protocol_handler_config<t_connection_context>::notify(int command, const epee::span<const uint8_t> in_buff, boost::uuids::uuid connection_id)
 {
   async_protocol_handler<t_connection_context>* aph;
   int r = find_and_lock_connection(connection_id, aph);