Add a ‘verifyStore’ RPC

Hello!

The patch below adds a ‘verifyStore’ RPC with the same signature as the
current LocalStore::verifyStore method.

Thanks,
Ludo’.

>From aef46c03ca77eb6344f4892672eb6d9d06432041 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= <ludo@gnu.org>
Date: Mon, 1 Jun 2015 23:17:10 +0200
Subject: [PATCH] Add a 'verifyStore' remote procedure call.

5 files changed, 27 insertions, 1 deletions

diff --git a/nix/libstore/remote-store.cc b/nix/libstore/remote-store.cc
index 140fe9cf4e..0539bbe127 100644
--- a/nix/libstore/remote-store.cc
+++ b/nix/libstore/remote-store.cc
@@ -585,6 +585,16 @@ void RemoteStore::optimiseStore()
     readInt(from);
 }
 
+bool RemoteStore::verifyStore(bool checkContents, bool repair)
+{
+    openConnection();
+    writeInt(wopVerifyStore, to);
+    writeInt(checkContents, to);
+    writeInt(repair, to);
+    processStderr();
+    return readInt(from) != 0;
+}
+
 void RemoteStore::processStderr(Sink * sink, Source * source)
 {
     to.flush();
diff --git a/nix/libstore/remote-store.hh b/nix/libstore/remote-store.hh
index 14209cbfb5..030120db40 100644
--- a/nix/libstore/remote-store.hh
+++ b/nix/libstore/remote-store.hh
@@ -85,6 +85,7 @@ public:
 
     void optimiseStore();
 
+    bool verifyStore(bool checkContents, bool repair);
 private:
     AutoCloseFD fdSocket;
     FdSink to;
diff --git a/nix/libstore/store-api.hh b/nix/libstore/store-api.hh
index 97a60a6a5c..3764f3e542 100644
--- a/nix/libstore/store-api.hh
+++ b/nix/libstore/store-api.hh
@@ -254,6 +254,10 @@ public:
     /* Optimise the disk space usage of the Nix store by hard-linking files
        with the same contents. */
     virtual void optimiseStore() = 0;
+
+    /* Check the integrity of the Nix store.  Returns true if errors
+       remain. */
+    virtual bool verifyStore(bool checkContents, bool repair) = 0;
 };
 
 
diff --git a/nix/libstore/worker-protocol.hh b/nix/libstore/worker-protocol.hh
index 4b040b77ce..d037d7402e 100644
--- a/nix/libstore/worker-protocol.hh
+++ b/nix/libstore/worker-protocol.hh
@@ -42,7 +42,8 @@ typedef enum {
     wopQueryValidPaths = 31,
     wopQuerySubstitutablePaths = 32,
     wopQueryValidDerivers = 33,
-    wopOptimiseStore = 34
+    wopOptimiseStore = 34,
+    wopVerifyStore = 35
 } WorkerOp;
 
 
diff --git a/nix/nix-daemon/nix-daemon.cc b/nix/nix-daemon/nix-daemon.cc
index 580198956a..96a4e4b773 100644
--- a/nix/nix-daemon/nix-daemon.cc
+++ b/nix/nix-daemon/nix-daemon.cc
@@ -647,6 +647,16 @@ static void performOp(bool trusted, unsigned int clientVersion,
         writeInt(1, to);
         break;
 
+    case wopVerifyStore: {
+	bool checkContents = readInt(from) != 0;
+	bool repair = readInt(from) != 0;
+	startWork();
+	bool errors = store->verifyStore(checkContents, repair);
+	stopWork();
+	writeInt(errors, to);
+	break;
+    }
+
     default:
         throw Error(format("invalid operation %1%") % op);
     }