Added size to block locators, touching most of the code.

[arvados.git] / sdk / go / blockdigest / blockdigest.go

diff --git a/sdk/go/blockdigest/blockdigest.go b/sdk/go/blockdigest/blockdigest.go
index 5c29b902f2727b7353e66d1f5da2fe934eb4e8e6..d2f1c60ba93889614de18756dcf3ed6608f0b5fa 100644 (file)
--- a/sdk/go/blockdigest/blockdigest.go
+++ b/sdk/go/blockdigest/blockdigest.go
@@ -4,9 +4,14 @@ package blockdigest
 import (
        "fmt"
        "log"
+       "regexp"
        "strconv"
+       "strings"
 )
 
+var LocatorPattern = regexp.MustCompile(
+       "^[0-9a-fA-F]{32}\\+[0-9]+(\\+[A-Z][A-Za-z0-9@_-]+)*$")
+
 // Stores a Block Locator Digest compactly, up to 128 bits.
 // Can be used as a map key.
 type BlockDigest struct {
@@ -14,10 +19,25 @@ type BlockDigest struct {
        L uint64
 }
 
+type DigestWithSize struct {
+       Digest BlockDigest
+       Size   uint32
+}
+
+type BlockLocator struct {
+       Digest BlockDigest
+       Size   int
+       Hints  []string
+}
+
 func (d BlockDigest) String() string {
        return fmt.Sprintf("%016x%016x", d.H, d.L)
 }
 
+func (w DigestWithSize) String() string {
+       return fmt.Sprintf("%s+%d", w.Digest.String(), w.Size)
+}
+
 // Will create a new BlockDigest unless an error is encountered.
 func FromString(s string) (dig BlockDigest, err error) {
        if len(s) != 32 {
@@ -46,3 +66,34 @@ func AssertFromString(s string) BlockDigest {
        }
        return d
 }
+
+func IsBlockLocator(s string) bool {
+       return LocatorPattern.MatchString(s)
+}
+
+func ParseBlockLocator(s string) (b BlockLocator, err error) {
+       if !LocatorPattern.MatchString(s) {
+               err = fmt.Errorf("String \"%s\" does not match BlockLocator pattern "+
+                       "\"%s\".",
+                       s,
+                       LocatorPattern.String())
+       } else {
+               tokens := strings.Split(s, "+")
+               var blockSize int64
+               var blockDigest BlockDigest
+               // We expect both of the following to succeed since LocatorPattern
+               // restricts the strings appropriately.
+               blockDigest, err = FromString(tokens[0])
+               if err != nil {
+                       return
+               }
+               blockSize, err = strconv.ParseInt(tokens[1], 10, 0)
+               if err != nil {
+                       return
+               }
+               b.Digest = blockDigest
+               b.Size = int(blockSize)
+               b.Hints = tokens[2:]
+       }
+       return
+}