Replaced the code to substitute host address part in URL

with libcurl library calls. This solution should be more robust
than a homebrew URL parser solution.

src/slic3r/GUI/Plater.cpp

@@ -2219,6 +2219,7 @@ Plater::priv::~priv()
 {
     if (config != nullptr)
         delete config;
+    // Saves the database of visited (already shown) hints into hints.ini.
     notification_manager->deactivate_loaded_hints();
 }
 

src/slic3r/Utils/OctoPrint.cpp

@@ -5,13 +5,15 @@
 #include <exception>
 #include <boost/format.hpp>
 #include <boost/log/trivial.hpp>
-#include <boost/nowide/convert.hpp>
 #include <boost/property_tree/ptree.hpp>
 #include <boost/property_tree/json_parser.hpp>
 #include <boost/algorithm/string/predicate.hpp>
 
+#include <curl/curl.h>
+
 #include <wx/progdlg.h>
 
+#include "slic3r/GUI/GUI.hpp"
 #include "slic3r/GUI/I18N.hpp"
 #include "slic3r/GUI/GUI.hpp"
 #include "Http.hpp"
@@ -25,8 +27,13 @@ namespace pt = boost::property_tree;
 namespace Slic3r {
 
 namespace {
-std::string substitute_host(const std::string& orig_addr, const std::string sub_addr)
+std::string substitute_host(const std::string& orig_addr, std::string sub_addr)
 {
+    // put ipv6 into [] brackets 
+    if (sub_addr.find(':') != std::string::npos && sub_addr.at(0) != '[')
+        sub_addr = "[" + sub_addr + "]";
+
+#if 0
     //URI = scheme ":"["//"[userinfo "@"] host [":" port]] path["?" query]["#" fragment]
     std::string final_addr = orig_addr;
     //  http
@@ -52,6 +59,35 @@ std::string substitute_host(const std::string& orig_addr, const std::string sub_
     }
     final_addr.replace(host_start, host_end - host_start, sub_addr);
     return final_addr;
+#else
+    // Using the new CURL API for handling URL. https://everything.curl.dev/libcurl/url
+    // If anything fails, return the input unchanged.
+    std::string out = orig_addr;
+    CURLU *hurl = curl_url();
+    if (hurl) {
+        // Parse the input URL.
+        CURLUcode rc = curl_url_set(hurl, CURLUPART_URL, orig_addr.c_str(), 0);
+        if (rc == CURLUE_OK) {
+            // Replace the address.
+            rc = curl_url_set(hurl, CURLUPART_HOST, sub_addr.c_str(), 0);
+            if (rc == CURLUE_OK) {
+                // Extract a string fromt the CURL URL handle.
+                char *url;
+                rc = curl_url_get(hurl, CURLUPART_URL, &url, 0);
+                if (rc == CURLUE_OK) {
+                    out = url;
+                    curl_free(url);
+                } else
+                    BOOST_LOG_TRIVIAL(error) << "OctoPrint substitute_host: failed to extract the URL after substitution";
+            } else
+                BOOST_LOG_TRIVIAL(error) << "OctoPrint substitute_host: failed to substitute host " << sub_addr << " in URL " << orig_addr;
+        } else
+            BOOST_LOG_TRIVIAL(error) << "OctoPrint substitute_host: failed to parse URL " << orig_addr;
+        curl_url_cleanup(hurl);
+    } else
+        BOOST_LOG_TRIVIAL(error) << "OctoPrint substitute_host: failed to allocate curl_url";
+    return out;
+#endif
 }
 } //namespace
 
@@ -110,7 +146,7 @@ bool OctoPrint::test(wxString &msg) const
 #ifdef WIN32
         .ssl_revoke_best_effort(m_ssl_revoke_best_effort)
         .on_ip_resolve([&](std::string address) {
-            msg = boost::nowide::widen(address);
+            msg = GUI::from_u8(address);
         })
 #endif
         .perform_sync();
@@ -138,9 +174,11 @@ bool OctoPrint::upload(PrintHostUpload upload_data, ProgressFn prorgess_fn, Erro
     const auto upload_filename = upload_data.upload_path.filename();
     const auto upload_parent_path = upload_data.upload_path.parent_path();
 
-    wxString test_msg;
+    // If test fails, test_msg_or_host_ip contains the error message.
-    if (! test(test_msg)) {
+    // Otherwise on Windows it contains the resolved IP address of the host.
-        error_fn(std::move(test_msg));
+    wxString test_msg_or_host_ip;
+    if (! test(test_msg_or_host_ip)) {
+        error_fn(std::move(test_msg_or_host_ip));
         return false;
     }
 
@@ -149,23 +187,18 @@ bool OctoPrint::upload(PrintHostUpload upload_data, ProgressFn prorgess_fn, Erro
 
     bool allow_ip_resolve = GUI::get_app_config()->get("allow_ip_resolve") == "1";
 
-    if (m_host.find("https://") == 0 || test_msg.empty() || !allow_ip_resolve) {
+    if (m_host.find("https://") == 0 || test_msg_or_host_ip.empty() || !allow_ip_resolve) {
         // If https is entered we assume signed ceritificate is being used
         // IP resolving will not happen - it could resolve into address not being specified in cert
         url = make_url("api/files/local");
     } else {
         // Curl uses easy_getinfo to get ip address of last successful transaction.
         // If it got the address use it instead of the stored in "host" variable.
-        // This new address returns in "test_msg" variable.
+        // This new address returns in "test_msg_or_host_ip" variable.
         // Solves troubles of uploades failing with name address.
-        std::string resolved_addr = boost::nowide::narrow(test_msg);
-        // put ipv6 into [] brackets 
-        if (resolved_addr.find(':') != std::string::npos && resolved_addr.at(0) != '[')
-            resolved_addr = "[" + resolved_addr + "]";
         // in original address (m_host) replace host for resolved ip 
-        std::string final_addr = substitute_host(m_host, resolved_addr);
+        url = substitute_host(make_url("api/files/local", m_host), GUI::into_u8(test_msg_or_host_ip));
-        BOOST_LOG_TRIVIAL(debug) << "Upload address after ip resolve: " << final_addr;
+        BOOST_LOG_TRIVIAL(info) << "Upload address after ip resolve: " << url;
-        url = make_url("api/files/local", final_addr);
     }
 
     BOOST_LOG_TRIVIAL(info) << boost::format("%1%: Uploading file %2% at %3%, filename: %4%, path: %5%, print: %6%")

src/slic3r/Utils/TCPConsole.hpp

@@ -13,6 +13,8 @@ namespace Utils {
 
 using boost::asio::ip::tcp;
 
+// Generic command / response TCP telnet like console class.
+// Used by the MKS host to send G-code commands to test connection ("M105") and to start printing ("M23 filename", "M24").
 class TCPConsole
 {
 public: