do not merge: debug rootPath

Signed-off-by: Aleksa Sarai <[email protected]>
moby · Jun 5, 2024 · 960520f · 960520f
1 parent af5a749
commit 960520f
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Showing 2 changed files with 18 additions and 3 deletions.
diff --git a/cache/contenthash/path.go b/cache/contenthash/path.go
@@ -8,6 +8,7 @@
 package contenthash
 
 import (
+ "fmt"
  "os"
  "path/filepath"
  "strings"
@@ -19,6 +20,10 @@ var errTooManyLinks = errors.New("too many links")
 
 const maxSymlinkLimit = 255
 
+var logFn = func(format string, v ...interface{}) {
+ fmt.Fprintf(os.Stderr, format, v...)
+}
+
 type onSymlinkFunc func(string, string) error
 
 // rootPath joins a path with a root, evaluating and bounding any symlink to
@@ -35,9 +40,13 @@ func rootPath(root, unsafePath string, followTrailing bool, cb onSymlinkFunc) (s
  currentPath string
  linksWalked int
  )
+ logFn("rootPath(%s, %s, %v)\n", root, unsafePath, followTrailing)
  for unsafePath != "" {
+ logFn("-- loop --\ncurrentPath: %s\nunsafePath: %s\n", currentPath, unsafePath)
+
  // Windows-specific: remove any drive letters from the path.
  if v := filepath.VolumeName(unsafePath); v != "" {
+ logFn("unsafePath %s -> [%s] %s\n", unsafePath, v, unsafePath[len(v):])
  unsafePath = unsafePath[len(v):]
  }
 
@@ -51,11 +60,13 @@ func rootPath(root, unsafePath string, followTrailing bool, cb onSymlinkFunc) (s
  } else {
  part, unsafePath = unsafePath[:i], unsafePath[i+1:]
  }
+ logFn("unsafePath -> (%s, %s)\n", part, unsafePath)
 
  // Apply the component lexically to the path we are building. path does
  // not contain any symlinks, and we are lexically dealing with a single
  // component, so it's okay to do filepath.Clean here.
  nextPath := filepath.Join(string(filepath.Separator), currentPath, part)
+ logFn("nextPath <- %s\n", nextPath)
  if nextPath == string(filepath.Separator) {
  // If we end up back at the root, we don't need to re-evaluate /.
  currentPath = ""
@@ -65,6 +76,7 @@ func rootPath(root, unsafePath string, followTrailing bool, cb onSymlinkFunc) (s
 
  // Figure out whether the path is a symlink.
  fi, err := os.Lstat(fullPath)
+ logFn("Lstat(%s) -> %v, %v\n", fullPath, fi, err)
  if err != nil && !errors.Is(err, os.ErrNotExist) {
  return "", err
  }
@@ -88,6 +100,7 @@ func rootPath(root, unsafePath string, followTrailing bool, cb onSymlinkFunc) (s
  }
 
  dest, err := os.Readlink(fullPath)
+ logFn("Readlink(%s) -> %v, %v\n", fullPath, dest, err)
  if err != nil {
  return "", err
  }
@@ -97,6 +110,7 @@ func rootPath(root, unsafePath string, followTrailing bool, cb onSymlinkFunc) (s
  }
  }
 
+ logFn("unsafePath <- %s + %s\n", dest, unsafePath)
  unsafePath = dest + string(filepath.Separator) + unsafePath
  // Absolute symlinks reset any work we've already done.
  if filepath.IsAbs(dest) {

diff --git a/cache/contenthash/path_test.go b/cache/contenthash/path_test.go
@@ -12,7 +12,6 @@ import (
 )
 
 func TestRootPathSymlinks(t *testing.T) {
- t.Parallel()
  tmpdir := t.TempDir()
 
  // Make the following tree:
@@ -106,12 +105,14 @@ func TestRootPathSymlinks(t *testing.T) {
  } {
  test := test // capture range variable
  t.Run(fmt.Sprintf("resolve(%q,followTrailing=%v)", test.path, test.followTrailing), func(t *testing.T) {
- t.Parallel()
+ logFn = func(fmt string, v ...interface{}) {
+ t.Logf(fmt, v...)
+ }
 
  resolvedPath, err := rootPath(tmpdir, test.path, test.followTrailing, nil)
  require.NoError(t, err)
 
- expectedPath := filepath.Join(tmpdir, test.expected)
+ expectedPath := filepath.Join(tmpdir, filepath.FromSlash(test.expected))
  require.Equal(t, expectedPath, resolvedPath)
  })
  }