git-gui: use only the configured shell

git-gui has a few places where a bare "sh" is passed to exec, meaning
that the first instance of "sh" on $PATH will be used rather than the
shell configured. This violates expectations that the configured shell
is being used. Let's use [shellpath] everywhere.

Signed-off-by: Mark Levedahl <mlevedahl@gmail.com>
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Taylor Blau <me@ttaylorr.com>

lib/sshkey.tcl

@@ -83,7 +83,8 @@ proc make_ssh_key {w} {
 	set sshkey_title [mc "Generating..."]
 	$w.header.gen configure -state disabled
 
-	set cmdline [list sh -c {echo | ssh-keygen -q -t rsa -f ~/.ssh/id_rsa 2>&1}]
+	set cmdline [list [shellpath] -c \
+		{echo | ssh-keygen -q -t rsa -f ~/.ssh/id_rsa 2>&1}]
 
 	if {[catch { set sshkey_fd [_open_stdout_stderr $cmdline] } err]} {
 		error_popup [mc "Could not start ssh-keygen:\n\n%s" $err]

lib/tools.tcl

@@ -110,14 +110,14 @@ proc tools_exec {fullname} {
 
 	set cmdline $repo_config(guitool.$fullname.cmd)
 	if {[is_config_true "guitool.$fullname.noconsole"]} {
-		tools_run_silent [list sh -c $cmdline] \
+		tools_run_silent [list [shellpath] -c $cmdline] \
 				 [list tools_complete $fullname {}]
 	} else {
 		regsub {/} $fullname { / } title
 		set w [console::new \
 			[mc "Tool: %s" $title] \
 			[mc "Running: %s" $cmdline]]
-		console::exec $w [list sh -c $cmdline] \
+		console::exec $w [list [shellpath] -c $cmdline] \
 				 [list tools_complete $fullname $w]
 	}