cmd/pack: use log.SetPrefix to make log calls more compact and consistent

Taking my own advice from a review of addr2line.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/65950044

diff --git a/src/cmd/pack/pack.go b/src/cmd/pack/pack.go
index 21dee72614c3b1f7f72d1c299945e9ddc249fec2..9996ec975398f2f3d9b6f30f715d451361a27049 100644 (file)
--- a/src/cmd/pack/pack.go
+++ b/src/cmd/pack/pack.go
@@ -43,6 +43,7 @@ func usage() {
 
 func main() {
        log.SetFlags(0)
+       log.SetPrefix("pack: ")
        // need "pack op archive" at least.
        if len(os.Args) < 3 {
                usage()
@@ -67,7 +68,7 @@ func main() {
                usage()
        }
        if len(ar.files) > 0 {
-               log.Fatalf("pack: file %q not in archive", ar.files[0])
+               log.Fatalf("file %q not in archive", ar.files[0])
        }
 }
 
@@ -124,7 +125,7 @@ func archive(name string, mode int, files []string) *Archive {
                fd, err = create(name)
        }
        if err != nil {
-               log.Fatal("pack: ", err)
+               log.Fatal(err)
        }
        mustBeArchive(fd)
        return &Archive{
@@ -150,7 +151,7 @@ func mustBeArchive(fd *os.File) {
        buf := make([]byte, len(arHeader))
        _, err := io.ReadFull(fd, buf)
        if err != nil || string(buf) != arHeader {
-               log.Fatal("pack: file is not an archive: bad header")
+               log.Fatal("file is not an archive: bad header")
        }
 }
 
@@ -183,19 +184,19 @@ func (ar *Archive) readMetadata() *Entry {
                return nil
        }
        if err != nil || buf[entryLen-2] != '`' || buf[entryLen-1] != '\n' {
-               log.Fatal("pack: file is not an archive: bad entry")
+               log.Fatal("file is not an archive: bad entry")
        }
        entry := new(Entry)
        entry.name = strings.TrimRight(string(buf[:16]), " ")
        if len(entry.name) == 0 {
-               log.Fatal("pack: file is not an archive: bad name")
+               log.Fatal("file is not an archive: bad name")
        }
        buf = buf[16:]
        str := string(buf)
        get := func(width, base, bitsize int) int64 {
                v, err := strconv.ParseInt(strings.TrimRight(str[:width], " "), base, bitsize)
                if err != nil {
-                       log.Fatal("pack: file is not an archive: bad number in entry: ", err)
+                       log.Fatal("file is not an archive: bad number in entry: ", err)
                }
                str = str[width:]
                return v
@@ -234,15 +235,15 @@ func listEntry(ar *Archive, entry *Entry, verbose bool) {
 func (ar *Archive) output(entry *Entry, w io.Writer) {
        n, err := io.Copy(w, io.LimitReader(ar.fd, entry.size))
        if err != nil {
-               log.Fatal("pack: ", err)
+               log.Fatal(err)
        }
        if n != entry.size {
-               log.Fatal("pack: short file")
+               log.Fatal("short file")
        }
        if entry.size&1 == 1 {
                _, err := ar.fd.Seek(1, 1)
                if err != nil {
-                       log.Fatal("pack: ", err)
+                       log.Fatal(err)
                }
        }
 }
@@ -255,7 +256,7 @@ func (ar *Archive) skip(entry *Entry) {
        }
        _, err := ar.fd.Seek(size, 1)
        if err != nil {
-               log.Fatal("pack: ", err)
+               log.Fatal(err)
        }
 }
 
@@ -288,7 +289,7 @@ func (ar *Archive) addFiles() {
                }
                fd, err := os.Open(file)
                if err != nil {
-                       log.Fatal("pack: ", err)
+                       log.Fatal(err)
                }
                ar.addFile(fd)
        }
@@ -310,7 +311,7 @@ func (ar *Archive) addFile(fd FileLike) {
        // First, get its info.
        info, err := fd.Stat()
        if err != nil {
-               log.Fatal("pack: ", err)
+               log.Fatal(err)
        }
        // mtime, uid, gid are all zero so repeated builds produce identical output.
        mtime := int64(0)
@@ -318,19 +319,19 @@ func (ar *Archive) addFile(fd FileLike) {
        gid := 0
        n, err := fmt.Fprintf(ar.fd, entryHeader, exactly16Bytes(info.Name()), mtime, uid, gid, info.Mode(), info.Size())
        if err != nil || n != entryLen {
-               log.Fatal("pack: writing entry header: ", err)
+               log.Fatal("writing entry header: ", err)
        }
        n64, err := io.Copy(ar.fd, fd)
        if err != nil {
-               log.Fatal("pack: writing file: ", err)
+               log.Fatal("writing file: ", err)
        }
        if n64 != info.Size() {
-               log.Fatal("pack: writing file: wrote %d bytes; file is size %d", n64, info.Size())
+               log.Fatal("writing file: wrote %d bytes; file is size %d", n64, info.Size())
        }
        if info.Size()&1 == 1 {
                _, err = ar.fd.Write([]byte{0})
                if err != nil {
-                       log.Fatal("pack: writing archive: ", err)
+                       log.Fatal("writing archive: ", err)
                }
        }
 }
@@ -387,7 +388,7 @@ func (ar *Archive) extractContents(entry *Entry) {
                }
                fd, err := os.OpenFile(entry.name, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, entry.mode)
                if err != nil {
-                       log.Fatal("pack: ", err)
+                       log.Fatal(err)
                }
                ar.output(entry, fd)
                fd.Close()