QPID-1148 - from Manuel Tiera

Lock file abstraction in sys/ with implementation portable to Linux and Solaris.

Changes by myself:
 - Makefile.am - must be updated for any new/renamed/removed source files.
 - Exception.h, Daemon.h, LockFile.h: Replaced throwIf() with if (...) throw ErrnoException(...)

The idiom throwIf(call-system-function(), "msg", errno) is incorret
(my fault, not Manuels). It assumes the first argument that makes a
system call call will be evaluated before the last one which fetches
errno. This may not be true on some compilers/platforms.


git-svn-id: https://svn.apache.org/repos/asf/incubator/qpid/trunk/qpid@674865 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 6 insertions, 18 deletions

diff --git a/cpp/src/qpid/DataDir.cpp b/cpp/src/qpid/DataDir.cpp
index 879f4de202..18b52b9b8f 100644
--- a/cpp/src/qpid/DataDir.cpp
+++ b/cpp/src/qpid/DataDir.cpp
@@ -26,13 +26,13 @@
 #include <sys/file.h>
 #include <fcntl.h>
 #include <cerrno>
+#include <unistd.h>
 
 namespace qpid {
 
 DataDir::DataDir (std::string path) :
     enabled (!path.empty ()),
-    dirPath (path),
-    dirFd(-1)
+    dirPath (path)
 {
     if (!enabled)
     {
@@ -50,24 +50,12 @@ DataDir::DataDir (std::string path) :
         else
             throw Exception ("Data directory not found: " + path);
     }
-    int dirFd = ::open(path.c_str(), 0);
-    if (dirFd == -1)
-        throw Exception(QPID_MSG("Can't open data directory: " << dirPath << ": " << strError(errno)));
-    int result = ::flock(dirFd, LOCK_EX | LOCK_NB);
-    if (result != 0) {
-        if (errno == EWOULDBLOCK)
-            throw Exception(QPID_MSG("Data directory locked by another process: " << path));
-        throw  Exception(QPID_MSG("Cannot lock data directory: " << strError(errno)));
-    }
-    QPID_LOG (info, "Locked data directory: " << dirPath);
+    std::string lockFileName(path);
+    lockFileName += "/lock";
+    lockFile = std::auto_ptr<sys::LockFile>(new sys::LockFile(lockFileName, true));
 }
 
-DataDir::~DataDir () {
-    if (dirFd != -1) {
-        ::close(dirFd);         // Closing the fd unlocks the directory.
-        QPID_LOG (info, "Unlocked data directory: " << dirPath);
-    }
-}
+DataDir::~DataDir () {}
 
 } // namespace qpid