Add command 'nix store copy-log'

Fixes #5222.

1 files changed, 40 insertions, 0 deletions

diff --git a/src/nix/store-copy-log.cc b/src/nix/store-copy-log.cc
new file mode 100644
index 000000000..fa6436cd0
--- /dev/null
+++ b/src/nix/store-copy-log.cc
@@ -0,0 +1,40 @@
+#include "command.hh"
+#include "shared.hh"
+#include "store-api.hh"
+#include "sync.hh"
+#include "thread-pool.hh"
+
+#include <atomic>
+
+using namespace nix;
+
+struct CmdCopyLog : virtual CopyCommand, virtual InstallablesCommand
+{
+    std::string description() override
+    {
+        return "copy build logs between Nix stores";
+    }
+
+    std::string doc() override
+    {
+        return
+          #include "store-copy-log.md"
+          ;
+    }
+
+    Category category() override { return catUtility; }
+
+    void run(ref<Store> srcStore) override
+    {
+        auto dstStore = getDstStore();
+
+        for (auto & path : toDerivations(srcStore, installables, true)) {
+            if (auto log = srcStore->getBuildLog(path))
+                dstStore->addBuildLog(path, *log);
+            else
+                throw Error("build log for '%s' is not available", srcStore->printStorePath(path));
+        }
+    }
+};
+
+static auto rCmdCopyLog = registerCommand2<CmdCopyLog>({"store", "copy-log"});