WIP 6

src/gridcoin/upgrade.cpp

@@ -485,12 +485,34 @@ void Upgrade::CleanupBlockchainData()
 {
     fs::path CleanupPath = GetDataDir();
 
+    // This is required because of problems with junction point handling in the boost filesystem library. Please see
+    // https://github.com/boostorg/filesystem/issues/125. We are not quite ready to switch over to std::filesystem yet.
+    // 1. I don't know whether the issue is fixed there, and
+    // 2. Not all C++17 compilers have the filesystem headers, since this was merged from boost in 2017.
+    //
+    // I don't believe it is very common for Windows users to redirect the Gridcoin data directory with a junction point,
+    // but it is certainly possible. We should handle it as gracefully as possible.
     if (fs::is_symlink(CleanupPath))
     {
-        LogPrintf("INFO: %s: Data directory is a symlink. True path is %s.",
-                  __func__, fs::read_symlink(CleanupPath).string());
+        LogPrintf("INFO: %s: Data directory is a symlink.",
+                  __func__);
 
-        CleanupPath = fs::read_symlink(CleanupPath);
+        try
+        {
+            LogPrintf("INFO: %s: True path for the symlink is %s.", __func__, fs::read_symlink(CleanupPath).string());
+
+            CleanupPath = fs::read_symlink(CleanupPath);
+        }
+        catch (fs::filesystem_error &ex)
+        {
+            error("%s: The data directory symlink or junction point cannot be resolved to the true canonical path. "
+                  "This can happen on Windows. Please change the data directory specified to the actual true path "
+                  "using the  -datadir=<path> option and try again.", __func__);
+
+            DownloadStatus.SetCleanupBlockchainDataFailed(true);
+
+            return;
+        }
     }
 
     unsigned int total_items = 0;