Merge branch 'ta/wait-on-aliased-commands-upon-signal' into master

When an aliased command, whose output is piped to a pager by git,
gets killed by a signal, the pager got into a funny state, which
has been corrected (again).

* ta/wait-on-aliased-commands-upon-signal:
  Wait for child on signal death for aliases to externals
  Wait for child on signal death for aliases to builtins

Author: gitster

git.c

@@ -346,6 +346,8 @@ static int handle_alias(int *argcp, const char ***argv)
 			commit_pager_choice();
 
 			child.use_shell = 1;
+			child.clean_on_exit = 1;
+			child.wait_after_clean = 1;
 			child.trace2_child_class = "shell_alias";
 			argv_array_push(&child.args, alias_string + 1);
 			argv_array_pushv(&child.args, (*argv) + 1);
@@ -767,7 +769,7 @@ static int run_argv(int *argcp, const char ***argv)
 			 * OK to return. Otherwise, we just pass along the status code.
 			 */
 			i = run_command_v_opt_tr2(args.argv, RUN_SILENT_EXEC_FAILURE |
-						  RUN_CLEAN_ON_EXIT, "git_alias");
+						  RUN_CLEAN_ON_EXIT | RUN_WAIT_AFTER_CLEAN, "git_alias");
 			if (i >= 0 || errno != ENOENT)
 				exit(i);
 			die("could not execute builtin %s", **argv);

run-command.c

@@ -1039,6 +1039,7 @@ int run_command_v_opt_cd_env_tr2(const char **argv, int opt, const char *dir,
 	cmd.silent_exec_failure = opt & RUN_SILENT_EXEC_FAILURE ? 1 : 0;
 	cmd.use_shell = opt & RUN_USING_SHELL ? 1 : 0;
 	cmd.clean_on_exit = opt & RUN_CLEAN_ON_EXIT ? 1 : 0;
+	cmd.wait_after_clean = opt & RUN_WAIT_AFTER_CLEAN ? 1 : 0;
 	cmd.dir = dir;
 	cmd.env = env;
 	cmd.trace2_child_class = tr2_class;

run-command.h

@@ -229,6 +229,7 @@ int run_auto_gc(int quiet);
 #define RUN_SILENT_EXEC_FAILURE 8
 #define RUN_USING_SHELL 16
 #define RUN_CLEAN_ON_EXIT 32
+#define RUN_WAIT_AFTER_CLEAN 64
 
 /**
  * Convenience functions that encapsulate a sequence of