Merge pull request #1841

b553c282 rpc: fix BUILD_TAG mispelling (BUILDTAG) (moneromooo-monero)
02097c87 core: print the "new update found" message in cyan, for visibility (moneromooo-monero)
749ebace download: check available disk space before downloading (moneromooo-monero)
f36c5f1e download: give download threads distinct names (moneromooo-monero)
f6211322 core: make update download cancellable (moneromooo-monero)
63f0e074 download: async API (moneromooo-monero)
9bf017ed http_client: allow cancelling a download (moneromooo-monero)
0d90123c http_client: allow derived class to get headers at start (moneromooo-monero)

5 files changed, 224 insertions, 46 deletions

diff --git a/src/common/download.cpp b/src/common/download.cpp
index c5ee797d0..28aac5a59 100644
--- a/src/common/download.cpp
+++ b/src/common/download.cpp
@@ -27,6 +27,7 @@
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include <string>
+#include <atomic>
 #include <boost/filesystem.hpp>
 #include <boost/asio.hpp>
 #include <boost/thread/thread.hpp>
@@ -40,27 +41,82 @@
 
 namespace tools
 {
-  static bool download_thread(const std::string &path, const std::string &url)
+  struct download_thread_control
   {
+    const std::string path;
+    const std::string uri;
+    std::function<void(const std::string&, const std::string&, bool)> result_cb;
+    std::function<bool(const std::string&, const std::string&, size_t, ssize_t)> progress_cb;
+    bool stop;
+    bool stopped;
+    bool success;
+    boost::thread thread;
+    boost::mutex mutex;
+
+    download_thread_control(const std::string &path, const std::string &uri, std::function<void(const std::string&, const std::string&, bool)> result_cb, std::function<bool(const std::string&, const std::string&, size_t, ssize_t)> progress_cb):
+        path(path), uri(uri), result_cb(result_cb), progress_cb(progress_cb), stop(false), stopped(false), success(false) {}
+    ~download_thread_control() { if (thread.joinable()) thread.detach(); }
+  };
+
+  static void download_thread(download_async_handle control)
+  {
+    static std::atomic<unsigned int> thread_id(0);
+
+    MLOG_SET_THREAD_NAME("DL" + std::to_string(thread_id++));
+
+    struct stopped_setter
+    {
+      stopped_setter(const download_async_handle &control): control(control) {}
+      ~stopped_setter() { control->stopped = true; }
+      download_async_handle control;
+    } stopped_setter(control);
+
     try
     {
-      MINFO("Downloading " << url << " to " << path);
+      boost::unique_lock<boost::mutex> lock(control->mutex);
+      MINFO("Downloading " << control->uri << " to " << control->path);
       std::ofstream f;
-      f.open(path, std::ios_base::binary | std::ios_base::out | std::ios_base::trunc);
+      f.open(control->path, std::ios_base::binary | std::ios_base::out | std::ios_base::trunc);
       if (!f.good()) {
-        MERROR("Failed to open file " << path);
-        return false;
+        MERROR("Failed to open file " << control->path);
+        control->result_cb(control->path, control->uri, control->success);
+        return;
       }
       class download_client: public epee::net_utils::http::http_simple_client
       {
       public:
-        download_client(std::ofstream &f): f(f) {}
+        download_client(download_async_handle control, std::ofstream &f):
+          control(control), f(f), content_length(-1), total(0) {}
         virtual ~download_client() { f.close(); }
+        virtual bool on_header(const epee::net_utils::http::http_response_info &headers)
+        {
+          ssize_t length;
+          if (epee::string_tools::get_xtype_from_string(length, headers.m_header_info.m_content_length) && length >= 0)
+          {
+            MINFO("Content-Length: " << length);
+            content_length = length;
+            boost::filesystem::path path(control->path);
+            boost::filesystem::space_info si = boost::filesystem::space(path);
+            if (si.available < (size_t)content_length)
+            {
+              const uint64_t avail = (si.available + 1023) / 1024, needed = (content_length + 1023) / 1024;
+              MERROR("Not enough space to download " << needed << " kB to " << path << " (" << avail << " kB available)");
+              return false;
+            }
+          }
+          return true;
+        }
         virtual bool handle_target_data(std::string &piece_of_transfer)
         {
           try
           {
+            boost::lock_guard<boost::mutex> lock(control->mutex);
+            if (control->stop)
+              return false;
             f << piece_of_transfer;
+            total += piece_of_transfer.size();
+            if (control->progress_cb && !control->progress_cb(control->path, control->uri, total, content_length))
+              return false;
             return f.good();
           }
           catch (const std::exception &e)
@@ -70,69 +126,145 @@ namespace tools
           }
         }
       private:
+        download_async_handle control;
         std::ofstream &f;
-      } client(f);
+        ssize_t content_length;
+        size_t total;
+      } client(control, f);
       epee::net_utils::http::url_content u_c;
-      if (!epee::net_utils::parse_url(url, u_c))
+      if (!epee::net_utils::parse_url(control->uri, u_c))
       {
-        MWARNING("Failed to parse URL " << url);
-        return false;
+        MERROR("Failed to parse URL " << control->uri);
+        control->result_cb(control->path, control->uri, control->success);
+        return;
       }
       if (u_c.host.empty())
       {
-        MWARNING("Failed to determine address from URL " << url);
-        return false;
+        MERROR("Failed to determine address from URL " << control->uri);
+        control->result_cb(control->path, control->uri, control->success);
+        return;
       }
+
+      lock.unlock();
+
       uint16_t port = u_c.port ? u_c.port : 80;
       MDEBUG("Connecting to " << u_c.host << ":" << port);
       client.set_server(u_c.host, std::to_string(port), boost::none);
       if (!client.connect(std::chrono::seconds(30)))
       {
-        MERROR("Failed to connect to " << url);
-        return false;
+        boost::lock_guard<boost::mutex> lock(control->mutex);
+        MERROR("Failed to connect to " << control->uri);
+        control->result_cb(control->path, control->uri, control->success);
+        return;
       }
       MDEBUG("GETting " << u_c.uri);
       const epee::net_utils::http::http_response_info *info = NULL;
       if (!client.invoke_get(u_c.uri, std::chrono::seconds(30), "", &info))
       {
-        MERROR("Failed to connect to " << url);
+        boost::lock_guard<boost::mutex> lock(control->mutex);
+        MERROR("Failed to connect to " << control->uri);
         client.disconnect();
-        return false;
+        control->result_cb(control->path, control->uri, control->success);
+        return;
+      }
+      if (control->stop)
+      {
+        boost::lock_guard<boost::mutex> lock(control->mutex);
+        MDEBUG("Download cancelled");
+        client.disconnect();
+        control->result_cb(control->path, control->uri, control->success);
+        return;
       }
       if (!info)
       {
-        MERROR("Failed invoking GET command to " << url << ", no status info returned");
+        boost::lock_guard<boost::mutex> lock(control->mutex);
+        MERROR("Failed invoking GET command to " << control->uri << ", no status info returned");
         client.disconnect();
-        return false;
+        control->result_cb(control->path, control->uri, control->success);
+        return;
       }
       MDEBUG("response code: " << info->m_response_code);
+      MDEBUG("response length: " << info->m_header_info.m_content_length);
       MDEBUG("response comment: " << info->m_response_comment);
       MDEBUG("response body: " << info->m_body);
       for (const auto &f: info->m_additional_fields)
         MDEBUG("additional field: " << f.first << ": " << f.second);
       if (info->m_response_code != 200)
       {
+        boost::lock_guard<boost::mutex> lock(control->mutex);
         MERROR("Status code " << info->m_response_code);
         client.disconnect();
-        return false;
+        control->result_cb(control->path, control->uri, control->success);
+        return;
       }
       client.disconnect();
       f.close();
       MDEBUG("Download complete");
-      return true;
+      lock.lock();
+      control->success = true;
+      control->result_cb(control->path, control->uri, control->success);
+      return;
     }
     catch (const std::exception &e)
     {
       MERROR("Exception in download thread: " << e.what());
-      return false;
+      // fall through and call result_cb not from the catch block to avoid another exception
     }
+    boost::lock_guard<boost::mutex> lock(control->mutex);
+    control->result_cb(control->path, control->uri, control->success);
   }
 
-  bool download(const std::string &path, const std::string &url)
+  bool download(const std::string &path, const std::string &url, std::function<bool(const std::string&, const std::string&, size_t, ssize_t)> cb)
   {
-    bool success;
-    std::unique_ptr<boost::thread> thread(new boost::thread([&](){ success = download_thread(path, url); }));
-    thread->join();
+    bool success = false;
+    download_async_handle handle = download_async(path, url, [&success](const std::string&, const std::string&, bool result) {success = result;}, cb);
+    download_wait(handle);
     return success;
   }
+
+  download_async_handle download_async(const std::string &path, const std::string &url, std::function<void(const std::string&, const std::string&, bool)> result, std::function<bool(const std::string&, const std::string&, size_t, ssize_t)> progress)
+  {
+    download_async_handle control = std::make_shared<download_thread_control>(path, url, result, progress);
+    control->thread = boost::thread([control](){ download_thread(control); });
+    return control;
+  }
+
+  bool download_finished(const download_async_handle &control)
+  {
+    CHECK_AND_ASSERT_MES(control != 0, false, "NULL async download handle");
+    boost::lock_guard<boost::mutex> lock(control->mutex);
+    return control->stopped;
+  }
+
+  bool download_error(const download_async_handle &control)
+  {
+    CHECK_AND_ASSERT_MES(control != 0, false, "NULL async download handle");
+    boost::lock_guard<boost::mutex> lock(control->mutex);
+    return !control->success;
+  }
+
+  bool download_wait(const download_async_handle &control)
+  {
+    CHECK_AND_ASSERT_MES(control != 0, false, "NULL async download handle");
+    {
+      boost::lock_guard<boost::mutex> lock(control->mutex);
+      if (control->stopped)
+        return true;
+    }
+    control->thread.join();
+    return true;
+  }
+
+  bool download_cancel(const download_async_handle &control)
+  {
+    CHECK_AND_ASSERT_MES(control != 0, false, "NULL async download handle");
+    {
+      boost::lock_guard<boost::mutex> lock(control->mutex);
+      if (control->stopped)
+        return true;
+      control->stop = true;
+    }
+    control->thread.join();
+    return true;
+  }
 }
diff --git a/src/common/download.h b/src/common/download.h
index ab7644689..917cb2278 100644
--- a/src/common/download.h
+++ b/src/common/download.h
@@ -32,5 +32,13 @@
 
 namespace tools
 {
-  bool download(const std::string &path, const std::string &url);
+  struct download_thread_control;
+  typedef std::shared_ptr<download_thread_control> download_async_handle;
+
+  bool download(const std::string &path, const std::string &url, std::function<bool(const std::string&, const std::string&, size_t, ssize_t)> progress = NULL);
+  download_async_handle download_async(const std::string &path, const std::string &url, std::function<void(const std::string&, const std::string&, bool)> result, std::function<bool(const std::string&, const std::string&, size_t, ssize_t)> progress = NULL);
+  bool download_error(const download_async_handle &h);
+  bool download_finished(const download_async_handle &h);
+  bool download_wait(const download_async_handle &h);
+  bool download_cancel(const download_async_handle &h);
 }
diff --git a/src/cryptonote_core/cryptonote_core.cpp b/src/cryptonote_core/cryptonote_core.cpp
index cfe3b5441..9c5fae4ef 100644
--- a/src/cryptonote_core/cryptonote_core.cpp
+++ b/src/cryptonote_core/cryptonote_core.cpp
@@ -75,7 +75,8 @@ namespace cryptonote
               m_target_blockchain_height(0),
               m_checkpoints_path(""),
               m_last_dns_checkpoints_update(0),
-              m_last_json_checkpoints_update(0)
+              m_last_json_checkpoints_update(0),
+              m_update_download(0)
   {
     set_cryptonote_protocol(pprotocol);
   }
@@ -134,6 +135,15 @@ namespace cryptonote
   void core::stop()
   {
     m_blockchain_storage.cancel();
+
+    tools::download_async_handle handle;
+    {
+      boost::lock_guard<boost::mutex> lock(m_update_mutex);
+      handle = m_update_download;
+      m_update_download = 0;
+    }
+    if (handle)
+      tools::download_cancel(handle);
   }
   //-----------------------------------------------------------------------------------
   void core::init_options(boost::program_options::options_description& desc)
@@ -1118,7 +1128,7 @@ namespace cryptonote
       return true;
 
     std::string url = tools::get_update_url(software, subdir, buildtag, version, true);
-    MGINFO("Version " << version << " of " << software << " for " << buildtag << " is available: " << url << ", SHA256 hash " << hash);
+    MCLOG_CYAN(el::Level::Info, "global", "Version " << version << " of " << software << " for " << buildtag << " is available: " << url << ", SHA256 hash " << hash);
 
     if (check_updates_level == UPDATES_NOTIFY)
       return true;
@@ -1133,32 +1143,55 @@ namespace cryptonote
     boost::filesystem::path path(epee::string_tools::get_current_module_folder());
     path /= filename;
 
+    boost::unique_lock<boost::mutex> lock(m_update_mutex);
+
+    if (m_update_download != 0)
+    {
+      MCDEBUG("updates", "Already downloading update");
+      return true;
+    }
+
     crypto::hash file_hash;
     if (!tools::sha256sum(path.string(), file_hash) || (hash != epee::string_tools::pod_to_hex(file_hash)))
     {
       MCDEBUG("updates", "We don't have that file already, downloading");
-      if (!tools::download(path.string(), url))
-      {
-        MCERROR("updates", "Failed to download " << url);
-        return false;
-      }
-      if (!tools::sha256sum(path.string(), file_hash))
-      {
-        MCERROR("updates", "Failed to hash " << path);
-        return false;
-      }
-      if (hash != epee::string_tools::pod_to_hex(file_hash))
-      {
-        MCERROR("updates", "Download from " << url << " does not match the expected hash");
-        return false;
-      }
-      MGINFO("New version downloaded to " << path);
+      m_last_update_length = 0;
+      m_update_download = tools::download_async(path.string(), url, [this, hash](const std::string &path, const std::string &uri, bool success) {
+        if (success)
+        {
+          crypto::hash file_hash;
+          if (!tools::sha256sum(path, file_hash))
+          {
+            MCERROR("updates", "Failed to hash " << path);
+          }
+          if (hash != epee::string_tools::pod_to_hex(file_hash))
+          {
+            MCERROR("updates", "Download from " << uri << " does not match the expected hash");
+          }
+          MCLOG_CYAN(el::Level::Info, "updates", "New version downloaded to " << path);
+        }
+        else
+        {
+          MCERROR("updates", "Failed to download " << uri);
+        }
+        boost::unique_lock<boost::mutex> lock(m_update_mutex);
+        m_update_download = 0;
+      }, [this](const std::string &path, const std::string &uri, size_t length, ssize_t content_length) {
+        if (length >= m_last_update_length + 1024 * 1024 * 10)
+        {
+          m_last_update_length = length;
+          MCDEBUG("updates", "Downloaded " << length << "/" << (content_length ? std::to_string(content_length) : "unknown"));
+        }
+        return true;
+      });
     }
     else
     {
       MCDEBUG("updates", "We already have " << path << " with expected hash");
     }
 
+    lock.unlock();
+
     if (check_updates_level == UPDATES_DOWNLOAD)
       return true;
 
diff --git a/src/cryptonote_core/cryptonote_core.h b/src/cryptonote_core/cryptonote_core.h
index 7323bef29..02d58691d 100644
--- a/src/cryptonote_core/cryptonote_core.h
+++ b/src/cryptonote_core/cryptonote_core.h
@@ -39,6 +39,7 @@
 #include "p2p/net_node_common.h"
 #include "cryptonote_protocol/cryptonote_protocol_handler_common.h"
 #include "storages/portable_storage_template_helper.h"
+#include "common/download.h"
 #include "tx_pool.h"
 #include "blockchain.h"
 #include "cryptonote_basic/miner.h"
@@ -844,6 +845,10 @@ namespace cryptonote
        UPDATES_DOWNLOAD,
        UPDATES_UPDATE,
      } check_updates_level;
+
+     tools::download_async_handle m_update_download;
+     size_t m_last_update_length;
+     boost::mutex m_update_mutex;
    };
 }
 
diff --git a/src/rpc/core_rpc_server.cpp b/src/rpc/core_rpc_server.cpp
index b114f77ae..9f7e8aa38 100644
--- a/src/rpc/core_rpc_server.cpp
+++ b/src/rpc/core_rpc_server.cpp
@@ -1491,8 +1491,8 @@ namespace cryptonote
   bool core_rpc_server::on_update(const COMMAND_RPC_UPDATE::request& req, COMMAND_RPC_UPDATE::response& res)
   {
     static const char software[] = "monero";
-#ifdef BUILDTAG
-    static const char buildtag[] = BOOST_PP_STRINGIZE(BUILDTAG);
+#ifdef BUILD_TAG
+    static const char buildtag[] = BOOST_PP_STRINGIZE(BUILD_TAG);
 #else
     static const char buildtag[] = "source";
 #endif