From: Denis Vlasenko Date: Tue, 1 Jul 2008 10:40:41 +0000 (-0000) Subject: *: introduce and use xvfork() X-Git-Tag: 1_12_0~258 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=3da5572bfa81a63ce66e41b99e9801c47a05bbbf;p=oweals%2Fbusybox.git *: introduce and use xvfork() function old new delta time_main 1052 1285 +233 crontab_main 623 856 +233 ifupdown_main 2202 2403 +201 xvfork - 20 +20 passwd_main 1049 1053 +4 grave 1068 1066 -2 script_main 935 921 -14 vfork_or_die 20 - -20 vfork_compressor 206 175 -31 open_as_user 109 - -109 popen2 218 - -218 edit_file 910 690 -220 run_command 268 - -268 ------------------------------------------------------------------------------ (add/remove: 1/4 grow/shrink: 4/4 up/down: 691/-882) Total: -191 bytes --- diff --git a/archival/libunarchive/open_transformer.c b/archival/libunarchive/open_transformer.c index a6bc62321..16ca6a59c 100644 --- a/archival/libunarchive/open_transformer.c +++ b/archival/libunarchive/open_transformer.c @@ -25,9 +25,7 @@ int FAST_FUNC open_transformer(int src_fd, if (pid == -1) bb_perror_msg_and_die("can't fork"); #else - pid = vfork(); - if (pid == -1) - bb_perror_msg_and_die("can't vfork"); + pid = xvfork(); #endif if (pid == 0) { diff --git a/archival/tar.c b/archival/tar.c index 526edb69d..17ac6c55a 100644 --- a/archival/tar.c +++ b/archival/tar.c @@ -536,9 +536,7 @@ static void NOINLINE vfork_compressor(int tar_fd, int gzip) (void) &zip_exec; #endif - gzipPid = vfork(); - if (gzipPid < 0) - bb_perror_msg_and_die("can't vfork"); + gzipPid = xvfork(); if (gzipPid == 0) { /* child */ diff --git a/debianutils/start_stop_daemon.c b/debianutils/start_stop_daemon.c index 459fb77e0..f10572ddf 100644 --- a/debianutils/start_stop_daemon.c +++ b/debianutils/start_stop_daemon.c @@ -404,9 +404,7 @@ int start_stop_daemon_main(int argc ATTRIBUTE_UNUSED, char **argv) /* DAEMON_DEVNULL_STDIO is superfluous - * it's always done by bb_daemonize() */ #else - pid_t pid = vfork(); - if (pid < 0) /* error */ - bb_perror_msg_and_die("vfork"); + pid_t pid = xvfork(); if (pid != 0) { /* parent */ /* why _exit? the child may have changed the stack, diff --git a/include/libbb.h b/include/libbb.h index 54601f87b..33e465cf4 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -719,6 +719,8 @@ int bb_execvp(const char *file, char *const argv[]) FAST_FUNC; #define BB_EXECLP(prog,cmd,...) execlp(prog,cmd, __VA_ARGS__) #endif +pid_t xvfork(void) FAST_FUNC; + /* NOMMU friendy fork+exec */ pid_t spawn(char **argv) FAST_FUNC; pid_t xspawn(char **argv) FAST_FUNC; diff --git a/libbb/Kbuild b/libbb/Kbuild index 5cbecd537..5ace87cad 100644 --- a/libbb/Kbuild +++ b/libbb/Kbuild @@ -109,6 +109,7 @@ lib-y += xfunc_die.o lib-y += xgetcwd.o lib-y += xgethostbyname.o lib-y += xreadlink.o +lib-y += xvfork.o # conditionally compiled objects: lib-$(CONFIG_FEATURE_MOUNT_LOOP) += loop.o diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c index 37d4c274e..9baa813a1 100644 --- a/libbb/vfork_daemon_rexec.c +++ b/libbb/vfork_daemon_rexec.c @@ -226,9 +226,7 @@ void FAST_FUNC forkexit_or_rexec(char **argv) if (re_execed) return; - pid = vfork(); - if (pid < 0) /* wtf? */ - bb_perror_msg_and_die("vfork"); + pid = xvfork(); if (pid) /* parent */ exit(EXIT_SUCCESS); /* child - re-exec ourself */ diff --git a/miscutils/crontab.c b/miscutils/crontab.c index dc3179dac..4bba9fb44 100644 --- a/miscutils/crontab.c +++ b/miscutils/crontab.c @@ -38,10 +38,8 @@ static void change_user(const struct passwd *pas) static void edit_file(const struct passwd *pas, const char *file) { const char *ptr; - int pid = vfork(); + int pid = xvfork(); - if (pid < 0) /* failure */ - bb_perror_msg_and_die("vfork"); if (pid) { /* parent */ wait4pid(pid); return; @@ -65,9 +63,7 @@ static int open_as_user(const struct passwd *pas, const char *file) pid_t pid; char c; - pid = vfork(); - if (pid < 0) /* ERROR */ - bb_perror_msg_and_die("vfork"); + pid = xvfork(); if (pid) { /* PARENT */ if (wait4pid(pid) == 0) { /* exitcode 0: child says it can read */ diff --git a/miscutils/time.c b/miscutils/time.c index a6d158c53..104548c23 100644 --- a/miscutils/time.c +++ b/miscutils/time.c @@ -372,9 +372,7 @@ static void run_command(char *const *cmd, resource_t *resp) void (*quit_signal)(int); resp->elapsed_ms = monotonic_us() / 1000; - pid = vfork(); /* Run CMD as child process. */ - if (pid < 0) - bb_error_msg_and_die("cannot fork"); + pid = xvfork(); /* Run CMD as child process. */ if (pid == 0) { /* If child. */ /* Don't cast execvp arguments; that causes errors on some systems, versus merely warnings if the cast is left off. */ diff --git a/networking/ifupdown.c b/networking/ifupdown.c index c12391863..8caff3f4d 100644 --- a/networking/ifupdown.c +++ b/networking/ifupdown.c @@ -1008,12 +1008,9 @@ static int popen2(FILE **in, FILE **out, char *command, char *param) xpiped_pair(outfd); fflush(NULL); - pid = vfork(); + pid = xvfork(); - switch (pid) { - case -1: /* failure */ - bb_perror_msg_and_die("vfork"); - case 0: /* child */ + if (pid == 0) { /* child */ /* NB: close _first_, then move fds! */ close(infd.wr); close(outfd.rd); diff --git a/networking/sendmail.c b/networking/sendmail.c index 1c23ca290..c195cc021 100644 --- a/networking/sendmail.c +++ b/networking/sendmail.c @@ -120,15 +120,6 @@ static void signal_handler(int signo) #undef err } -/* libbb candidate */ -static pid_t vfork_or_die(void) -{ - pid_t pid = vfork(); - if (pid < 0) - bb_perror_msg_and_die("vfork"); - return pid; -} - static void launch_helper(const char **argv) { // setup vanilla unidirectional pipes interchange @@ -137,7 +128,7 @@ static void launch_helper(const char **argv) xpipe(pipes); xpipe(pipes+2); - helper_pid = vfork_or_die(); + helper_pid = xvfork(); idx = (!helper_pid) * 2; xdup2(pipes[idx], STDIN_FILENO); xdup2(pipes[3-idx], STDOUT_FILENO); diff --git a/shell/hush.c b/shell/hush.c index 72186f970..59d8f3f99 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -3096,9 +3096,11 @@ static FILE *generate_stream_from_list(struct pipe *head) * huge=`cat TESTFILE` # will block here forever * echo OK */ - pid = BB_MMU ? fork() : vfork(); + pid = BB_MMU ? fork() : xvfork(); +#if BB_MMU if (pid < 0) - bb_perror_msg_and_die(BB_MMU ? "fork" : "vfork"); + bb_perror_msg_and_die("fork"); +#endif if (pid == 0) { /* child */ if (ENABLE_HUSH_JOB) die_sleep = 0; /* let nofork's xfuncs die */ diff --git a/util-linux/script.c b/util-linux/script.c index e70294e6c..a6c1ab88a 100644 --- a/util-linux/script.c +++ b/util-linux/script.c @@ -87,10 +87,7 @@ int script_main(int argc ATTRIBUTE_UNUSED, char **argv) /* TODO: SIGWINCH? pass window size changes down to slave? */ - child_pid = vfork(); - if (child_pid < 0) { - bb_perror_msg_and_die("vfork"); - } + child_pid = xvfork(); if (child_pid) { /* parent */