From 537776e1f8ece6f1ef650aac2e2d609721a91577 Mon Sep 17 00:00:00 2001
From: James Turner <james@flightgear.org>
Date: Wed, 4 Nov 2020 11:22:48 +0000
Subject: [PATCH] TerraSync: fix local-file copying

Avoid downloading data corresponding to files shipped in FGData.
---
 simgear/io/HTTPRepository.cxx     | 64 +++++++++++++++++--------------
 simgear/scene/tsync/terrasync.cxx | 17 +++++---
 2 files changed, 46 insertions(+), 35 deletions(-)

diff --git a/simgear/io/HTTPRepository.cxx b/simgear/io/HTTPRepository.cxx
index c197d27a..d7db9539 100644
--- a/simgear/io/HTTPRepository.cxx
+++ b/simgear/io/HTTPRepository.cxx
@@ -221,42 +221,48 @@ public:
 		char* buf = nullptr;
 		size_t bufSize = 0;
 
-		for (const auto& child : children) {
-            if (child.type != HTTPRepository::FileType)
-                continue;
+                for (auto &child : children) {
+                  if (child.type != HTTPRepository::FileType)
+                    continue;
 
-            if (child.path.exists())
-                continue;
+                  if (child.path.exists())
+                    continue;
 
-            SGPath cp = _repository->installedCopyPath;
-            cp.append(relativePath());
-            cp.append(child.name);
-            if (!cp.exists()) {
-                continue;
-            }
+                  SGPath cp = _repository->installedCopyPath;
+                  cp.append(relativePath());
+                  cp.append(child.name);
+                  if (!cp.exists()) {
+                    continue;
+                  }
 
-            SGBinaryFile src(cp);
-			SGBinaryFile dst(child.path);
-			src.open(SG_IO_IN);
-			dst.open(SG_IO_OUT);
+                  SGBinaryFile src(cp);
+                  SGBinaryFile dst(child.path);
+                  src.open(SG_IO_IN);
+                  dst.open(SG_IO_OUT);
 
-			if (bufSize < cp.sizeInBytes()) {
-				bufSize = cp.sizeInBytes();
-				free(buf);
-				buf = (char*) malloc(bufSize);
-				if (!buf) {
-					continue;
-				}
-			}
+                  if (bufSize < cp.sizeInBytes()) {
+                    bufSize = cp.sizeInBytes();
+                    free(buf);
+                    buf = (char *)malloc(bufSize);
+                    if (!buf) {
+                      continue;
+                    }
+                  }
 
-			src.read(buf, cp.sizeInBytes());
-			dst.write(buf, cp.sizeInBytes());
-			src.close();
-			dst.close();
+                  src.read(buf, cp.sizeInBytes());
+                  dst.write(buf, cp.sizeInBytes());
+                  src.close();
+                  dst.close();
 
-		}
+                  // reset caching
+                  child.path.set_cached(false);
+                  child.path.set_cached(true);
 
-		free(buf);
+                  std::string hash = computeHashForPath(child.path);
+                  updatedFileContents(child.path, hash);
+                }
+
+                free(buf);
     }
 
     void updateChildrenBasedOnHash()
diff --git a/simgear/scene/tsync/terrasync.cxx b/simgear/scene/tsync/terrasync.cxx
index d208456a..e9702fad 100644
--- a/simgear/scene/tsync/terrasync.cxx
+++ b/simgear/scene/tsync/terrasync.cxx
@@ -603,12 +603,6 @@ void SGTerraSync::WorkerThread::updateSyncSlot(SyncSlot &slot)
             beginNormalSync(slot);
         }
 
-        if (_installRoot.exists()) {
-            SGPath p = _installRoot;
-            p.append(slot.currentItem._dir);
-            slot.repository->setInstalledCopyPath(p);
-        }
-
         try {
             slot.repository->update();
         } catch (sg_exception& e) {
@@ -676,6 +670,11 @@ void SGTerraSync::WorkerThread::beginSyncTile(SyncSlot& slot)
     slot.repository.reset(new HTTPRepository(path, &_http));
     slot.repository->setBaseUrl(_httpServer + "/" + tileCategory);
 
+    if (_installRoot.exists()) {
+      SGPath p = _installRoot / tileCategory;
+      slot.repository->setInstalledCopyPath(p);
+    }
+
     const auto dirPrefix = tenByTenDir + "/" + oneByOneDir;
 
     // filter callback to *only* sync the 1x1 dir we want, if it exists
@@ -706,6 +705,12 @@ void SGTerraSync::WorkerThread::beginNormalSync(SyncSlot& slot)
     path.append(slot.currentItem._dir);
     slot.repository.reset(new HTTPRepository(path, &_http));
     slot.repository->setBaseUrl(_httpServer + "/" + slot.currentItem._dir);
+
+    if (_installRoot.exists()) {
+      SGPath p = _installRoot;
+      p.append(slot.currentItem._dir);
+      slot.repository->setInstalledCopyPath(p);
+    }
 }
 
 void SGTerraSync::WorkerThread::runInternal()