commit-reach: make can_all_from_reach... linear

diff --git a/Documentation/git-update-ref.txt b/Documentation/git-update-ref.txt
index 0a0a5512b3c62eb1179a3d5a9687949c39b2a9ef..bc8fdfd4691326b44e2cbdea3dc4925cf7440515 100644 (file)
--- a/Documentation/git-update-ref.txt
+++ b/Documentation/git-update-ref.txt
@@ -8,7 +8,7 @@ git-update-ref - Update the object name stored in a ref safely
 SYNOPSIS
 --------
 [verse]
-'git update-ref' [-m <reason>] (-d <ref> [<oldvalue>] | [--no-deref] <ref> <newvalue> [<oldvalue>] | --stdin [-z])
+'git update-ref' [-m <reason>] (-d <ref> [<oldvalue>] | [--no-deref] [--create-reflog] <ref> <newvalue> [<oldvalue>] | --stdin [-z])
 
 DESCRIPTION
 -----------
@@ -67,8 +67,16 @@ performs all modifications together.  Specify commands of the form:
        verify SP <ref> [SP <oldvalue>] LF
        option SP <opt> LF
 
+With `--create-reflog`, update-ref will create a reflog for each ref
+even if one would not ordinarily be created.
+
 Quote fields containing whitespace as if they were strings in C source
-code.  Alternatively, use `-z` to specify commands without quoting:
+code; i.e., surrounded by double-quotes and with backslash escapes.
+Use 40 "0" characters or the empty string to specify a zero value.  To
+specify a missing value, omit the value and its preceding SP entirely.
+
+Alternatively, use `-z` to specify in NUL-terminated format, without
+quoting:
 
        update SP <ref> NUL <newvalue> NUL [<oldvalue>] NUL
        create SP <ref> NUL <newvalue> NUL
@@ -76,8 +84,12 @@ code.  Alternatively, use `-z` to specify commands without quoting:
        verify SP <ref> NUL [<oldvalue>] NUL
        option SP <opt> NUL
 
-Lines of any other format or a repeated <ref> produce an error.
-Command meanings are:
+In this format, use 40 "0" to specify a zero value, and use the empty
+string to specify a missing value.
+
+In either format, values can be specified in any form that Git
+recognizes as an object name.  Commands in any other format or a
+repeated <ref> produce an error.  Command meanings are:
 
 update::
        Set <ref> to <newvalue> after verifying <oldvalue>, if given.
@@ -102,16 +114,13 @@ option::
        The only valid option is `no-deref` to avoid dereferencing
        a symbolic ref.
 
-Use 40 "0" or the empty string to specify a zero value, except that
-with `-z` an empty <oldvalue> is considered missing.
-
 If all <ref>s can be locked with matching <oldvalue>s
 simultaneously, all modifications are performed.  Otherwise, no
 modifications are performed.  Note that while each individual
 <ref> is updated or deleted atomically, a concurrent reader may
 still see a subset of the modifications.
 
-Logging Updates
+LOGGING UPDATES
 ---------------
 If config parameter "core.logAllRefUpdates" is true and the ref is one under
 "refs/heads/", "refs/remotes/", "refs/notes/", or the symbolic ref HEAD; or