libutil: make AutoCloseFD a better resource

add a reset() method to close the wrapped fd instead of assigning magic
constants. also make the from-fd constructor explicit so you can't
accidentally assign the *wrong* magic constant, or even an unrelated
integer that also just happens to be an fd by pure chance.

Change-Id: I51311b0f6e040240886b5103d39d1794a6acc325

1 files changed, 3 insertions, 3 deletions

diff --git a/src/build-remote/build-remote.cc b/src/build-remote/build-remote.cc
index 118468477..04aade9db 100644
--- a/src/build-remote/build-remote.cc
+++ b/src/build-remote/build-remote.cc
@@ -126,7 +126,7 @@ static int main_build_remote(int argc, char * * argv)
             mkdir(currentLoad.c_str(), 0777);
 
             while (true) {
-                bestSlotLock = -1;
+                bestSlotLock.reset();
                 AutoCloseFD lock = openLockFile(currentLoad + "/main-lock", true);
                 lockFile(lock.get(), ltWrite, true);
 
@@ -229,7 +229,7 @@ static int main_build_remote(int argc, char * * argv)
                 futimens(bestSlotLock.get(), NULL);
 #endif
 
-                lock = -1;
+                lock.reset();
 
                 try {
 
@@ -282,7 +282,7 @@ connected:
             copyPaths(*store, *sshStore, store->parseStorePathSet(inputs), NoRepair, NoCheckSigs, substitute);
         }
 
-        uploadLock = -1;
+        uploadLock.reset();
 
         auto drv = store->readDerivation(*drvPath);