regulators: Support a string or vector for VPD

Add a 'byte_values' alternative to the 'value' entry in the compare VPD
action.  This is to support VPD values that are not strings, such as
'HW', a new IBM keyword that describes the version of a piece of
hardware.

To support this, the VPD class now treats all VPD keyword values as
vectors of uint8_ts, including in its data cache.  If a compare VPD
action in the JSON contains a string value, it will be converted to the
vector before the CompareVPDAction class is created.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I3fcabf896f4885feae1b07ee2c3da5929cf8bfa4
diff --git a/phosphor-regulators/src/actions/compare_vpd_action.cpp b/phosphor-regulators/src/actions/compare_vpd_action.cpp
index 1049cee..d7cccf0 100644
--- a/phosphor-regulators/src/actions/compare_vpd_action.cpp
+++ b/phosphor-regulators/src/actions/compare_vpd_action.cpp
@@ -30,7 +30,7 @@
     try
     {
         // Get actual VPD keyword value
-        std::string actualValue =
+        std::vector<uint8_t> actualValue =
             environment.getServices().getVPD().getValue(fru, keyword);
 
         // Check if actual value equals expected value
@@ -51,7 +51,13 @@
     ss << "compare_vpd: { ";
     ss << "fru: " << fru << ", ";
     ss << "keyword: " << keyword << ", ";
-    ss << "value: " << value << " }";
+    ss << "value: [ ";
+    ss << std::hex << std::uppercase;
+    for (unsigned int i = 0; i < value.size(); ++i)
+    {
+        ss << ((i > 0) ? ", " : "") << "0x" << static_cast<uint16_t>(value[i]);
+    }
+    ss << " ] }";
     return ss.str();
 }
 
diff --git a/phosphor-regulators/src/actions/compare_vpd_action.hpp b/phosphor-regulators/src/actions/compare_vpd_action.hpp
index af7e085..8825220 100644
--- a/phosphor-regulators/src/actions/compare_vpd_action.hpp
+++ b/phosphor-regulators/src/actions/compare_vpd_action.hpp
@@ -18,7 +18,9 @@
 #include "action.hpp"
 #include "action_environment.hpp"
 
+#include <cstdint>
 #include <string>
+#include <vector>
 
 namespace phosphor::power::regulators
 {
@@ -52,7 +54,7 @@
      */
     explicit CompareVPDAction(const std::string& fru,
                               const std::string& keyword,
-                              const std::string& value) :
+                              const std::vector<uint8_t>& value) :
         fru{fru},
         keyword{keyword}, value{value}
     {
@@ -96,7 +98,7 @@
      *
      * @return value
      */
-    const std::string& getValue() const
+    const std::vector<uint8_t>& getValue() const
     {
         return value;
     }
@@ -124,7 +126,7 @@
     /**
      * Expected value.
      */
-    const std::string value{};
+    const std::vector<uint8_t> value{};
 };
 
 } // namespace phosphor::power::regulators