Consistent precondition formatting

Our "Preconditions:" blocks are very useful to determine the input invariants,
but they are bit inconsistent throughout the codebase, which makes them harder
to read (particularly cases with 5+ conditions in a single paragraph).

I've reformatted all of the cases to fit in simple rules:

1. Cases with a single condition are placed on a single line.
2. Cases with multiple conditions are placed in a bulleted list.

This format has been added to the style guide.

I've also mentioned "Postconditions:", though those are much less frequently
used, and all uses already match this style.

PiperOrigin-RevId: 327687465

1 files changed, 6 insertions, 7 deletions

diff --git a/pkg/sentry/fs/copy_up.go b/pkg/sentry/fs/copy_up.go
index 735452b07..ff2fe6712 100644
--- a/pkg/sentry/fs/copy_up.go
+++ b/pkg/sentry/fs/copy_up.go
@@ -107,8 +107,7 @@ func copyUp(ctx context.Context, d *Dirent) error {
 // leave the upper filesystem filled with any number of parent directories
 // but the upper filesystem will never be in an inconsistent state.
 //
-// Preconditions:
-// - d.Inode.overlay is non-nil.
+// Preconditions: d.Inode.overlay is non-nil.
 func copyUpLockedForRename(ctx context.Context, d *Dirent) error {
 	for {
 		// Did we race with another copy up or does there
@@ -183,12 +182,12 @@ func doCopyUp(ctx context.Context, d *Dirent) error {
 // Returns a generic error on failure.
 //
 // Preconditions:
-// - parent.Inode.overlay.upper must be non-nil.
-// - next.Inode.overlay.copyMu must be locked writable.
-// - next.Inode.overlay.lower must be non-nil.
-// - next.Inode.overlay.lower.StableAttr.Type must be RegularFile, Directory,
+// * parent.Inode.overlay.upper must be non-nil.
+// * next.Inode.overlay.copyMu must be locked writable.
+// * next.Inode.overlay.lower must be non-nil.
+// * next.Inode.overlay.lower.StableAttr.Type must be RegularFile, Directory,
 //   or Symlink.
-// - upper filesystem must support setting file ownership and timestamps.
+// * upper filesystem must support setting file ownership and timestamps.
 func copyUpLocked(ctx context.Context, parent *Dirent, next *Dirent) error {
 	// Extract the attributes of the file we wish to copy.
 	attrs, err := next.Inode.overlay.lower.UnstableAttr(ctx)