*: introduce and use xfork() and xvfork()
function old new delta
launch_helper 170 169 -1
setup_heredoc 312 302 -10
handle_dir_common 367 354 -13
expand_vars_to_list 2456 2443 -13
open_transformer 89 74 -15
data_extract_to_command 439 423 -16
do_ipaddr 1406 1389 -17
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/7 up/down: 0/-85) Total: -85 bytes
Signed-off-by: Pascal Bellard <pascal.bellard@ads-lu.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/include/libbb.h b/include/libbb.h
index 4b6699f..e2a8322 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -841,6 +841,19 @@
#endif
int BB_EXECVP_or_die(char **argv) NORETURN FAST_FUNC;
+/* xvfork() can't be a _function_, return after vfork mangles stack
+ * in the parent. It must be a macro. */
+#define xvfork() \
+({ \
+ pid_t bb__xvfork_pid = vfork(); \
+ if (bb__xvfork_pid < 0) \
+ bb_perror_msg_and_die("vfork"); \
+ bb__xvfork_pid; \
+})
+#if BB_MMU
+pid_t xfork(void) FAST_FUNC;
+#endif
+
/* NOMMU friendy fork+exec: */
pid_t spawn(char **argv) FAST_FUNC;
pid_t xspawn(char **argv) FAST_FUNC;
@@ -886,7 +899,7 @@
* Both of the above will redirect fd 0,1,2 to /dev/null and drop ctty
* (will do setsid()).
*
- * fork_or_rexec(argv) = bare-bones "fork" on MMU,
+ * fork_or_rexec(argv) = bare-bones fork on MMU,
* "vfork + re-exec ourself" on NOMMU. No fd redirection, no setsid().
* On MMU ignores argv.
*
@@ -902,19 +915,19 @@
DAEMON_ONLY_SANITIZE = 8, /* internal use */
};
#if BB_MMU
- pid_t fork_or_rexec(void) FAST_FUNC;
enum { re_execed = 0 };
-# define fork_or_rexec(argv) fork_or_rexec()
+# define fork_or_rexec(argv) xfork()
# define bb_daemonize_or_rexec(flags, argv) bb_daemonize_or_rexec(flags)
# define bb_daemonize(flags) bb_daemonize_or_rexec(flags, bogus)
#else
+ extern bool re_execed;
void re_exec(char **argv) NORETURN FAST_FUNC;
pid_t fork_or_rexec(char **argv) FAST_FUNC;
- extern bool re_execed;
int BUG_fork_is_unavailable_on_nommu(void) FAST_FUNC;
int BUG_daemon_is_unavailable_on_nommu(void) FAST_FUNC;
void BUG_bb_daemonize_is_unavailable_on_nommu(void) FAST_FUNC;
# define fork() BUG_fork_is_unavailable_on_nommu()
+# define xfork() BUG_fork_is_unavailable_on_nommu()
# define daemon(a,b) BUG_daemon_is_unavailable_on_nommu()
# define bb_daemonize(a) BUG_bb_daemonize_is_unavailable_on_nommu()
#endif