feat(parse): envelope different OS GUP flags parsing

GUP flags are changed between different OS versions.
Create parsing functions to envelope the different type implemented to
parse the flags for each version.

Author: AlonZivony

helpers/argumentParsers.go

@@ -6,6 +6,7 @@ import (
 	"net"
 	"strconv"
 	"strings"
+	"sync/atomic"
 
 	"golang.org/x/sys/unix"
 )
@@ -3158,6 +3159,67 @@ func ParseLegacyGUPFlags(rawValue uint64) LegacyGUPFlag {
 	return LegacyGUPFlag{stringValue: strings.Join(f, "|"), rawValue: uint32(rawValue)}
 }
 
+var currentOSGUPFlagsParse uint32
+var skipDetermineGUPFlagsFunc uint32
+
+const gupFlagsChangeVersion = "6.3.0"
+
+// ParseGUPFlagsCurrentOS parse the GUP flags received according to current machine OS version.
+// It uses optimizations to perform better than ParseGUPFlagsForOS
+func ParseGUPFlagsCurrentOS(rawValue uint64) (SystemFunctionArgument, error) {
+	const (
+		newVersionsParsing = iota
+		legacyParsing
+	)
+	if atomic.LoadUint32(&skipDetermineGUPFlagsFunc) == 0 {
+		osInfo, err := GetOSInfo()
+		if err != nil {
+			return nil, fmt.Errorf("error getting current OS info - %s", err)
+		}
+		compare, err := osInfo.CompareOSBaseKernelRelease(gupFlagsChangeVersion)
+		if err != nil {
+			return nil, fmt.Errorf(
+				"error comparing OS versions to determine how to parse GUP flags - %s",
+				err,
+			)
+		}
+		if compare == KernelVersionOlder {
+			atomic.StoreUint32(&currentOSGUPFlagsParse, legacyParsing)
+		} else {
+			atomic.StoreUint32(&currentOSGUPFlagsParse, newVersionsParsing)
+		}
+		// Avoid doing this check in the future
+		atomic.StoreUint32(&skipDetermineGUPFlagsFunc, 1)
+	}
+
+	// Don't really need to use atomics here, as the value is only used here
+	// and is set in an atomic way
+	switch currentOSGUPFlagsParse {
+	case legacyParsing:
+		return ParseLegacyGUPFlags(rawValue), nil
+	case newVersionsParsing:
+		return ParseGUPFlags(rawValue), nil
+	default:
+		return nil, fmt.Errorf("no parsing function for GUP flags was found to this OD version")
+	}
+}
+
+// ParseGUPFlagsForOS parse the GUP flags received according to given OS version.
+func ParseGUPFlagsForOS(osInfo *OSInfo, rawValue uint64) (SystemFunctionArgument, error) {
+	compare, err := osInfo.CompareOSBaseKernelRelease(gupFlagsChangeVersion)
+	if err != nil {
+		return nil, fmt.Errorf(
+			"error comparing OS versions to determine how to parse GUP flags - %s",
+			err,
+		)
+	}
+
+	if compare == KernelVersionOlder {
+		return ParseLegacyGUPFlags(rawValue), nil
+	}
+	return ParseGUPFlags(rawValue), nil
+}
+
 // =====================================================
 
 // VmFlag represents the flags in the `vm_area_struct` in x86 64bit architecture