Optimise memory storage of dependency information

[goredo.git] / dep.go

diff --git a/dep.go b/dep.go
index 40245196c4b7a7a649eeabdbbac6c2ac9fe2cbaf..0add0a79c4329b7c6b701a8e0d880eea4c357b84 100644 (file)
--- a/dep.go
+++ b/dep.go
@@ -21,9 +21,11 @@ package main
 
 import (
        "bufio"
+       "bytes"
        "encoding/hex"
        "errors"
        "io"
+       "log"
        "os"
        "path"
 
@@ -64,28 +66,27 @@ func always(fdDep *os.File) error {
 }
 
 func stamp(fdDep, src *os.File) error {
-       var hsh string
        hsh, err := fileHash(src)
        if err != nil {
                return err
        }
-       tracef(CDebug, "stamp: %s <- %s", fdDep.Name(), hsh)
+       tracef(CDebug, "stamp: %s <- %s", fdDep.Name(), hex.EncodeToString(hsh))
        return recfileWrite(
                fdDep,
                recfile.Field{Name: "Type", Value: DepTypeStamp},
-               recfile.Field{Name: "Hash", Value: hsh},
+               recfile.Field{Name: "Hash", Value: hex.EncodeToString(hsh)},
        )
 }
 
-func fileHash(fd *os.File) (string, error) {
+func fileHash(fd *os.File) ([]byte, error) {
        h := blake3.New(32, nil)
        if _, err := io.Copy(h, bufio.NewReader(fd)); err != nil {
-               return "", err
+               return nil, err
        }
-       return hex.EncodeToString(h.Sum(nil)), nil
+       return h.Sum(nil), nil
 }
 
-func depWrite(fdDep *os.File, cwd, tgt, hsh string) error {
+func depWrite(fdDep *os.File, cwd, tgt string, hsh []byte) error {
        tracef(CDebug, "ifchange: %s <- %s", fdDep.Name(), tgt)
        fd, err := os.Open(path.Join(cwd, tgt))
        if err != nil {
@@ -99,7 +100,7 @@ func depWrite(fdDep *os.File, cwd, tgt, hsh string) error {
        if isDir {
                return nil
        }
-       if hsh == "" {
+       if hsh == nil {
                hsh, err = fileHash(fd)
                if err != nil {
                        return ErrLine(err)
@@ -108,7 +109,7 @@ func depWrite(fdDep *os.File, cwd, tgt, hsh string) error {
        fields := []recfile.Field{
                {Name: "Type", Value: DepTypeIfchange},
                {Name: "Target", Value: tgt},
-               {Name: "Hash", Value: hsh},
+               {Name: "Hash", Value: hex.EncodeToString(hsh)},
        }
        fields = append(fields, inode.RecfileFields()...)
        return recfileWrite(fdDep, fields...)
@@ -129,7 +130,7 @@ func depsWrite(fdDep *os.File, tgts []string) error {
                tgtDir := path.Join(cwd, DirPrefix)
                tgtRel := mustRel(tgtDir, tgtAbs)
                if _, errStat := os.Stat(tgt); errStat == nil {
-                       err = ErrLine(depWrite(fdDep, tgtDir, tgtRel, ""))
+                       err = ErrLine(depWrite(fdDep, tgtDir, tgtRel, nil))
                } else {
                        tracef(CDebug, "ifchange: %s <- %s (non-existing)", fdDep.Name(), tgtRel)
                        fields := []recfile.Field{
@@ -147,18 +148,36 @@ func depsWrite(fdDep *os.File, tgts []string) error {
        return nil
 }
 
+type DepInfoIfchange struct {
+       tgt   string
+       inode *Inode
+       hash  []byte
+}
+
 type DepInfo struct {
        build     string
        always    bool
-       stamp     string
+       stamp     []byte
        ifcreates []string
-       ifchanges []map[string]string
+       ifchanges []DepInfoIfchange
+}
+
+func mustHexDecode(s string) []byte {
+       b, err := hex.DecodeString(s)
+       if err != nil {
+               log.Fatal(err)
+       }
+       return b
 }
 
 var missingBuild = errors.New(".rec missing Build:")
 
-func depRead(fdDep io.Reader) (*DepInfo, error) {
-       r := recfile.NewReader(fdDep)
+func depRead(pth string) (*DepInfo, error) {
+       data, err := os.ReadFile(pth)
+       if err != nil {
+               return nil, err
+       }
+       r := recfile.NewReader(bytes.NewReader(data))
        m, err := r.NextMap()
        if err != nil {
                return nil, err
@@ -187,14 +206,21 @@ func depRead(fdDep io.Reader) (*DepInfo, error) {
                        }
                        depInfo.ifcreates = append(depInfo.ifcreates, dep)
                case DepTypeIfchange:
-                       delete(m, "Type")
-                       depInfo.ifchanges = append(depInfo.ifchanges, m)
+                       inode, err := inodeFromRec(m)
+                       if err != nil {
+                               log.Print(err)
+                               return nil, ErrBadRecFormat
+                       }
+                       hsh := mustHexDecode(m["Hash"])
+                       depInfo.ifchanges = append(depInfo.ifchanges, DepInfoIfchange{
+                               tgt: m["Target"], inode: inode, hash: hsh,
+                       })
                case DepTypeStamp:
                        hsh := m["Hash"]
                        if hsh == "" {
                                return nil, ErrBadRecFormat
                        }
-                       depInfo.stamp = hsh
+                       depInfo.stamp = mustHexDecode(hsh)
                default:
                        return nil, ErrBadRecFormat
                }