run-command: use vfork instead of fork vfork-test

To enable vfork, we merely have to avoid modifying memory we
share with the parent, so the guard functions
`child_(error|warn|die)_fn` can now be disabled.

FIXME: still missing autoconf + Makefile portability tweaks.

Signed-off-by: Eric Wong <e@80x24.org>

1 files changed, 1 insertions, 27 deletions

diff --git a/run-command.c b/run-command.c
index 9e36151bf9..0292dd94b6 100644
--- a/run-command.c
+++ b/run-command.c
@@ -324,25 +324,6 @@ static void fake_fatal(const char *err, va_list params)
         vreportf("fatal: ", err, params);
 }
 
-static void child_error_fn(const char *err, va_list params)
-{
-        const char msg[] = "error() should not be called in child\n";
-        xwrite(2, msg, sizeof(msg) - 1);
-}
-
-static void child_warn_fn(const char *err, va_list params)
-{
-        const char msg[] = "warn() should not be called in child\n";
-        xwrite(2, msg, sizeof(msg) - 1);
-}
-
-static void NORETURN child_die_fn(const char *err, va_list params)
-{
-        const char msg[] = "die() should not be called in child\n";
-        xwrite(2, msg, sizeof(msg) - 1);
-        _exit(2);
-}
-
 /* this runs in the parent process */
 static void child_err_spew(struct child_process *cmd, struct child_err *cerr)
 {
@@ -658,17 +639,10 @@ fail_pipe:
          * never be released in the child process.  This means only
          * Async-Signal-Safe functions are permitted in the child.
          */
-        cmd->pid = fork();
+        cmd->pid = vfork();
         failed_errno = errno;
         if (!cmd->pid) {
                 int sig;
-                /*
-                 * Ensure the default die/error/warn routines do not get
-                 * called, they can take stdio locks and malloc.
-                 */
-                set_die_routine(child_die_fn);
-                set_error_routine(child_error_fn);
-                set_warn_routine(child_warn_fn);
 
                 close(notify_pipe[0]);
                 set_cloexec(notify_pipe[1]);