Added ASC/ASCQ sense constants (from Linux kernel) and added a function to

pretty print the meaning of the ACS/ACSQ couple.

SCSI/Constants.hh

@@ -293,5 +293,24 @@ namespace SCSI {
       bytesWrittenToTape         = 0x0009  // a signed number and may be negative
     };
   };
-  
+
+  class senseConstants {
+  public:
+
+    /* Structures from the Linux Kernel. It holds ASC/ASCQ to string 
+     * translations (from http://www.t10.org/lists/asc-num.txt) */
+    struct error_info {
+      uint16_t code12; /* 0x0302 looks better than 0x03,0x02 */
+      const char * text;
+    };
+    static const struct error_info ascStrings[];
+
+    struct error_range_info {
+      uint8_t asc;
+      uint8_t ascq_min;
+      uint8_t ascq_max;
+      const char * text;
+    };
+    static const struct error_range_info ascRangesStrings[];
+  };
 }; // namespace SCSI

SCSI/Structures.cc

@@ -24,6 +24,7 @@
 #include "Structures.hh"
 
 #include <sstream>
+#include <cstdio>
 
 std::string SCSI::Structures::toString(const inquiryData_t& inq) {
   std::stringstream inqDump;
@@ -60,4 +61,3 @@ std::string SCSI::Structures::toString(const inquiryData_t& inq) {
     inqDump << "inq.versionDescriptor[" << i << "]=" << SCSI::Structures::toU16(inq.versionDescriptor[i]) << std::endl;
   return inqDump.str();
 }
-

SCSI/Structures.hh

@@ -608,7 +608,33 @@ namespace SCSI {
         } else {
           throw Tape::Exception("In senseData_t::getASCQ: no ACSQ with this response code or response code not supported");
         }
-      };
+      }
+      /**
+       * Function turning the ACS/ACSQ contents into a string.
+       * This function is taken from the Linux kernel sources.
+       * see scsi_extd_sense_format.
+       * @return the error string as defined by SCSI specifications.
+       */
+      std::string getACSString() {
+        SCSI::senseConstants sc;
+        uint8_t asc = getASC();
+        uint8_t ascq = getASCQ();
+        uint16_t code = (asc << 8) | ascq;
+        for (int i = 0; sc.ascStrings[i].text; i++)
+          if (sc.ascStrings[i].code12 == code)
+            return std::string(sc.ascStrings[i].text);
+        for (int i = 0; sc.ascRangesStrings[i].text; i++)
+          if (sc.ascRangesStrings[i].asc == asc &&
+                  sc.ascRangesStrings[i].ascq_min <= ascq &&
+                  sc.ascRangesStrings[i].ascq_max >= ascq) {
+            char buff[100];
+            snprintf(buff, sizeof (buff), sc.ascRangesStrings[i].text, ascq);
+            return std::string(buff);
+          }
+        char buff[100];
+        snprintf(buff, sizeof (buff), "Unknown ASC/ASCQ:%02x/%02x", asc, ascq);
+        return std::string(buff);
+      }
     };
     
     template <size_t n>
@@ -649,6 +675,5 @@ namespace SCSI {
       return hex.str();
     }
   };
-
-
 };
+

SCSI/StructuresTest.cc

@@ -412,17 +412,28 @@ namespace UnitTests {
     ASSERT_EQ(0x78, sense.getASCQ());
     
     buff[0] = 0x73;
-    buff[2] = 0x56;
-    buff[3] = 0x78;
+    buff[2] = 0x0b;
+    buff[3] = 0x08;
     ASSERT_EQ(false, sense.isCurrent());
     ASSERT_EQ(true, sense.isDeffered());
     ASSERT_EQ(false, sense.isFixedFormat());
     ASSERT_EQ(true, sense.isDescriptorFormat());
-    ASSERT_EQ(0x56, sense.getASC());
-    ASSERT_EQ(0x78, sense.getASCQ());
+    ASSERT_EQ(0x0b, sense.getASC());
+    ASSERT_EQ(0x08, sense.getASCQ());
+    ASSERT_EQ("Warning - power loss expected", sense.getACSString());
+    
+    buff[2] = 0x40;
+    buff[3] = 0xab;
+    ASSERT_EQ("Diagnostic failure on component (ab)", sense.getACSString());
+    
+    buff[2] = 0x00;
+    buff[3] = 0x1F;
+    ASSERT_EQ("Unknown ASC/ASCQ:00/1f", sense.getACSString());
     
     buff[0] = 0x74;
     ASSERT_THROW(sense.getASC(), Tape::Exception);
+    
+    ASSERT_THROW(sense.getACSString(), Tape::Exception);
   }
   
   TEST(SCSI_Structures, toU16) {