Fix the map configurations for Mars

Include hotfix for limiting the number of concurrent downloads

data/assets/scene/solarsystem/planets/mars/mars.asset

@@ -14,7 +14,7 @@ local textures = asset.syncedResource({
 
 local marsRadii = { 3396190.0, 3396190.0, 3376200.0 }
 
-local mapServiceConfigs = asset.localResource("mapServiceConfigs")
+local mapServiceConfigs = asset.localResource("map_service_configs")
 
 local color_layers = {
     {

include/openspace/util/httprequest.h

@@ -28,6 +28,7 @@
 #include <ghoul/filesystem/file.h>
 #include <ghoul/filesystem/directory.h>
 
+#include <atomic>
 #include <fstream>
 #include <functional>
 #include <memory>
@@ -174,6 +175,7 @@ protected:
     void markAsStarted();
     void markAsSuccessful();
     void markAsFailed();
+
 private:
     ProgressCallback _onProgress;
     bool _started = false;
@@ -187,6 +189,7 @@ public:
     SyncHttpDownload(SyncHttpDownload&& d) = default;
     virtual ~SyncHttpDownload() = default;
     void download(HttpRequest::RequestOptions opt);
+
 protected:
     HttpRequest _httpRequest;
 };
@@ -199,8 +202,10 @@ public:
     void start(HttpRequest::RequestOptions opt);
     void cancel();
     void wait();
+
 protected:
     void download(HttpRequest::RequestOptions opt);
+
 private:
     HttpRequest _httpRequest;
     std::thread _downloadThread;
@@ -218,16 +223,21 @@ public:
     HttpFileDownload(std::string destination, Overwrite = Overwrite::No);
     HttpFileDownload(HttpFileDownload&& d) = default;
     virtual ~HttpFileDownload() = default;
+
 protected:
     bool initDownload() override;
     bool deinitDownload() override;
     size_t handleData(HttpRequest::Data d) override;
 
     static std::mutex _directoryCreationMutex;
+
 private:
     std::string _destination;
     bool _overwrite;
     std::ofstream _file;
+
+    static const int MaxFilehandles = 35;
+    static std::atomic_int nCurrentFilehandles;
 };
 
 class HttpMemoryDownload : public virtual HttpDownload {
@@ -236,10 +246,12 @@ public:
     HttpMemoryDownload(HttpMemoryDownload&& d) = default;
     virtual ~HttpMemoryDownload() = default;
     const std::vector<char>& downloadedData();
+
 protected:
     bool initDownload() override;
     bool deinitDownload() override;
     size_t handleData(HttpRequest::Data d) override;
+
 private:
     std::vector<char> _downloadedData;
 };

src/util/httprequest.cpp

@@ -51,7 +51,7 @@
 namespace {
     constexpr const long StatusCodeOk = 200;
     constexpr const char* _loggerCat = "HttpRequest";
-}
+} // namespace
 
 namespace openspace {
 
@@ -298,9 +298,11 @@ const std::vector<char>& HttpMemoryDownload::downloadedData() {
 bool HttpMemoryDownload::initDownload() {
     return true;
 }
+
 bool HttpMemoryDownload::deinitDownload() {
     return true;
 }
+
 size_t HttpMemoryDownload::handleData(HttpRequest::Data d) {
     _downloadedData.insert(_downloadedData.end(), d.buffer, d.buffer + d.size);
     return d.size;
@@ -315,7 +317,7 @@ HttpFileDownload::HttpFileDownload(
 
 bool HttpFileDownload::initDownload() {
     if (!_overwrite && FileSys.fileExists(_destination)) {
-        LERROR("File " << _destination << " already exists!");
+        LWARNING("File " << _destination << " already exists!");
         return false;
     }
 
@@ -329,6 +331,12 @@ bool HttpFileDownload::initDownload() {
         }
     }
 
+    while (nCurrentFilehandles >= MaxFilehandles) {
+        std::this_thread::sleep_for(std::chrono::milliseconds(500));
+    }
+
+
+    ++nCurrentFilehandles;
     _file = std::ofstream(_destination, std::ofstream::binary);
 
     if (_file.fail()) {
@@ -348,8 +356,6 @@ bool HttpFileDownload::initDownload() {
 #endif
         if (errno) {
 #if defined(__unix__)
-            // We use strerror_r because it's threadsafe.
-            // GNU's strerror_r returns a string and may ignore buffer completely.
             char buffer[255];
             LERROR(
                 "Cannot open file " << destinationFile << ": " <<
@@ -373,6 +379,7 @@ bool HttpFileDownload::initDownload() {
 
 bool HttpFileDownload::deinitDownload() {
     _file.close();
+    --nCurrentFilehandles;
     return _file.good();
 }
 
@@ -381,6 +388,7 @@ size_t HttpFileDownload::handleData(HttpRequest::Data d) {
     return d.size;
 }
 
+std::atomic_int HttpFileDownload::nCurrentFilehandles = 0;
 std::mutex HttpFileDownload::_directoryCreationMutex;
 
 SyncHttpMemoryDownload::SyncHttpMemoryDownload(std::string url)