Re-download updates when their checksum no longer matches

The Mana World currently likes to just update its "TMW.zip" file,
whereas updates were always given unique names in the past. With this
change, the client checks the Adler32 checksum to know when it should
re-download an update file.

This matches the behavior of ManaPlus commit
96150f1aeacf55d311c41ffe12d9e754b1cda001.

1 files changed, 15 insertions, 19 deletions

diff --git a/src/gui/updaterwindow.cpp b/src/gui/updaterwindow.cpp
index 2861f973..54ce8aeb 100644
--- a/src/gui/updaterwindow.cpp
+++ b/src/gui/updaterwindow.cpp
@@ -70,10 +70,10 @@ std::vector<UpdateFile> loadXMLFile(const std::string &fileName)
             continue;
 
         UpdateFile file;
-        file.name = XML::getProperty(fileNode, "file", "");
-        file.hash = XML::getProperty(fileNode, "hash", "");
+        file.name = XML::getProperty(fileNode, "file", std::string());
+        file.hash = XML::getProperty(fileNode, "hash", std::string());
         file.type = XML::getProperty(fileNode, "type", "data");
-        file.desc = XML::getProperty(fileNode, "description", "");
+        file.desc = XML::getProperty(fileNode, "description", std::string());
         file.required = XML::getProperty(fileNode, "required", "yes") == "yes";
 
         files.push_back(file);
@@ -86,13 +86,14 @@ std::vector<UpdateFile> loadTxtFile(const std::string &fileName)
 {
     std::vector<UpdateFile> files;
     std::ifstream fileHandler;
-    fileHandler.open(fileName.c_str(), std::ios::in);
+    fileHandler.open(fileName, std::ios::in);
 
     if (fileHandler.is_open())
     {
         while (fileHandler.good())
         {
-            char name[256], hash[50];
+            char name[256];
+            char hash[50];
             fileHandler.getline(name, 256, ' ');
             fileHandler.getline(hash, 50);
 
@@ -101,7 +102,6 @@ std::vector<UpdateFile> loadTxtFile(const std::string &fileName)
             thisFile.hash = hash;
             thisFile.type = "data";
             thisFile.required = true;
-            thisFile.desc.clear();
 
             if (!thisFile.name.empty())
                 files.push_back(thisFile);
@@ -459,35 +459,31 @@ void UpdaterWindow::logic()
             {
                 if (mUpdateIndex < mUpdateFiles.size())
                 {
-                    UpdateFile thisFile = mUpdateFiles[mUpdateIndex];
+                    const UpdateFile &thisFile = mUpdateFiles[mUpdateIndex];
                     if (!thisFile.required)
                     {
-                        // This statement checks to see if the file type is music, and if download-music is true
-                        // If it fails, this statement returns true, and results in not downloading the file
-                        // Else it will ignore the break, and download the file.
-                        if ( !(thisFile.type == "music" && config.getBoolValue("download-music")) )
+                        if (!(thisFile.type == "music" && config.getBoolValue("download-music")))
                         {
                             mUpdateIndex++;
                             break;
                         }
                     }
                     mCurrentFile = thisFile.name;
-                    std::string checksum;
-                    checksum = thisFile.hash;
-                    std::stringstream ss(checksum);
+                    std::stringstream ss(thisFile.hash);
                     ss >> std::hex >> mCurrentChecksum;
 
-                    std::ifstream temp(
-                            (mUpdatesDir + "/" + mCurrentFile).c_str());
+                    std::string filename = mUpdatesDir + "/" + mCurrentFile;
+                    FILE *file = fopen(filename.c_str(), "r+b");
 
-                    if (!temp.is_open())
+                    if (!file || Net::Download::fadler32(file) != mCurrentChecksum)
                     {
-                        temp.close();
+                        if (file)
+                            fclose(file);
                         download();
                     }
                     else
                     {
-                        temp.close();
+                        fclose(file);
                         logger->log("%s already here", mCurrentFile.c_str());
                     }
                     mUpdateIndex++;