Added possibility to find a SCSI device in the list by following a symlink

castor/tape/tapeserver/SCSI/Device.cpp

@@ -60,6 +60,20 @@ SCSI::DeviceVector::DeviceVector(System::virtualWrapper& sysWrapper) : m_sysWrap
   sysWrapper.closedir(dirp);
 }
 
+SCSI::DeviceInfo & SCSI::DeviceVector::findBySymlink(std::string path) {
+  struct stat sbuff;
+  castor::exception::Errnum::throwOnMinusOne(
+      m_sysWrapper.stat(path.c_str(), &sbuff),
+      std::string("Could not stat path: ")+path);
+  for(std::vector<DeviceInfo>::iterator i = begin(); i!= end(); i++) {
+    if (i->nst == sbuff || i->st == sbuff) {
+      return *i;
+    }
+  }
+  throw SCSI::DeviceVector::NotFound(
+      std::string("Could not find tape device pointed to by ") + path);
+}
+
 std::string SCSI::DeviceVector::readfile(std::string path) {
   int fd;
   castor::exception::Errnum::throwOnMinusOne(

castor/tape/tapeserver/SCSI/Device.hpp

@@ -23,7 +23,8 @@
  *****************************************************************************/
 
 #pragma once
-#include <string>
+
+
 #include <vector>
 #include <regex.h>
 #include <sys/types.h>
@@ -32,6 +33,7 @@
 #include "../exception/Exception.hpp"
 #include "../utils/Regex.hpp"
 #include "Constants.hpp"
+#include <string>
 
 namespace castor {
 namespace tape {
@@ -54,12 +56,16 @@ namespace SCSI {
         major = -1;
         minor = -1;
       }
-      int major;
-      int minor;
+      unsigned int major;
+      unsigned int minor;
 
       bool operator !=(const DeviceFile& b) const {
         return major != b.major || minor != b.minor;
       }
+      
+      bool operator ==(const struct stat & sbuff) const {
+        return major == major(sbuff.st_rdev) && minor == minor(sbuff.st_rdev);
+      }
     };
     DeviceFile sg;
     DeviceFile st;
@@ -83,6 +89,21 @@ namespace SCSI {
      * (all code using templates must be in the header file)
      */
     DeviceVector(castor::tape::System::virtualWrapper & sysWrapper);
+    
+    /**
+     * Find an array element that shares the same device files as one pointed
+     * to as a path. This is designed to be used with a symlink like:
+     * /dev/tape_T10D6116 -> /dev/nst0
+     */
+    DeviceInfo & findBySymlink(std::string path);
+    
+    /**
+     * Exception for previous function
+     */
+    class NotFound: public castor::tape::Exception {
+    public:
+      NotFound(const std::string& what): castor::tape::Exception(what) {}
+    };
   private:
     castor::tape::System::virtualWrapper & m_sysWrapper;