git-gui: Internalize symbolic-ref HEAD reading logic
To improve performance on fork+exec impoverished systems (such as
Windows) we want to avoid running git-symbolic-ref on every rescan
if we can do so. A quick way to implement such an avoidance is to
just read the HEAD ref ourselves; we'll either see it as a symref
(starts with "ref: ") or we'll see it as a detached head (40 hex
digits). In either case we can treat that as our current branch.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
diff --git a/git-gui.sh b/git-gui.sh
index 3bd12d2..5dc2c67 100755
--- a/git-gui.sh
+++ b/git-gui.sh
@@ -262,6 +262,17 @@
return [eval exec git $args]
}
+proc current-branch {} {
+ set ref {}
+ set fd [open [gitdir HEAD] r]
+ if {[gets $fd ref] <16
+ || ![regsub {^ref: refs/heads/} $ref {} ref]} {
+ set ref {}
+ }
+ close $fd
+ return $ref
+}
+
auto_load tk_optionMenu
rename tk_optionMenu real__tkOptionMenu
proc tk_optionMenu {w varName args} {
@@ -410,15 +421,7 @@
set mh [list]
- if {[catch {set current_branch [git symbolic-ref HEAD]}]} {
- set current_branch {}
- } else {
- regsub ^refs/((heads|tags|remotes)/)? \
- $current_branch \
- {} \
- current_branch
- }
-
+ set current_branch [current-branch]
if {[catch {set hd [git rev-parse --verify HEAD]}]} {
set hd {}
set ct initial
@@ -1651,14 +1654,8 @@
browser {
set subcommand_args {rev?}
switch [llength $argv] {
- 0 {
- set current_branch [git symbolic-ref HEAD]
- regsub ^refs/((heads|tags|remotes)/)? \
- $current_branch {} current_branch
- }
- 1 {
- set current_branch [lindex $argv 0]
- }
+ 0 { set current_branch [current-branch] }
+ 1 { set current_branch [lindex $argv 0] }
default usage
}
browser::new $current_branch
@@ -1691,9 +1688,7 @@
unset is_path
if {$head eq {}} {
- set current_branch [git symbolic-ref HEAD]
- regsub ^refs/((heads|tags|remotes)/)? \
- $current_branch {} current_branch
+ set current_branch [current-branch]
} else {
set current_branch $head
}
