From: Pascal Bellard Date: Sun, 4 Jul 2010 13:32:38 +0000 (+0200) Subject: *: introduce and use xfork() and xvfork() X-Git-Tag: 1_17_0~6 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=926031b7640bf5aad2ffcd54b096911743a47d97;p=oweals%2Fbusybox.git *: 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 Signed-off-by: Denys Vlasenko --- diff --git a/archival/libunarchive/data_extract_to_command.c b/archival/libunarchive/data_extract_to_command.c index eb09439bc..95f5bc864 100644 --- a/archival/libunarchive/data_extract_to_command.c +++ b/archival/libunarchive/data_extract_to_command.c @@ -82,11 +82,8 @@ void FAST_FUNC data_extract_to_command(archive_handle_t *archive_handle) memset(tar_env, 0, sizeof(tar_env)); xpipe(p); - pid = BB_MMU ? fork() : vfork(); - switch (pid) { - case -1: - bb_perror_msg_and_die(BB_MMU ? "fork" : "vfork"); - case 0: + pid = BB_MMU ? xfork() : xvfork(); + if (pid == 0) { /* Child */ /* str2env(tar_env, TAR_FILETYPE, "f"); - parent should do it once */ oct2env(tar_env, TAR_MODE, file_header->mode); diff --git a/archival/libunarchive/open_transformer.c b/archival/libunarchive/open_transformer.c index 47c13e6f4..cba049f1f 100644 --- a/archival/libunarchive/open_transformer.c +++ b/archival/libunarchive/open_transformer.c @@ -19,19 +19,9 @@ void FAST_FUNC open_transformer(int fd, int pid; xpiped_pair(fd_pipe); - -#if BB_MMU - pid = fork(); - if (pid == -1) - bb_perror_msg_and_die("vfork" + 1); -#else - pid = vfork(); - if (pid == -1) - bb_perror_msg_and_die("vfork"); -#endif - + pid = BB_MMU ? xfork() : xvfork(); if (pid == 0) { - /* child process */ + /* Child */ close(fd_pipe.rd); /* we don't want to read from the parent */ // FIXME: error check? #if BB_MMU diff --git a/archival/tar.c b/archival/tar.c index f49fb129e..9dd74536e 100644 --- a/archival/tar.c +++ b/archival/tar.c @@ -514,9 +514,7 @@ static void NOINLINE vfork_compressor(int tar_fd, int gzip) (void) &zip_exec; # endif - gzipPid = vfork(); - if (gzipPid < 0) - bb_perror_msg_and_die("vfork"); + gzipPid = xvfork(); if (gzipPid == 0) { /* child */ diff --git a/debianutils/start_stop_daemon.c b/debianutils/start_stop_daemon.c index 3ded758bf..665f38fbd 100644 --- a/debianutils/start_stop_daemon.c +++ b/debianutils/start_stop_daemon.c @@ -409,9 +409,7 @@ int start_stop_daemon_main(int argc UNUSED_PARAM, 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/e2fsprogs/old_e2fsprogs/fsck.c b/e2fsprogs/old_e2fsprogs/fsck.c index dc029b65a..2a66d728a 100644 --- a/e2fsprogs/old_e2fsprogs/fsck.c +++ b/e2fsprogs/old_e2fsprogs/fsck.c @@ -612,7 +612,7 @@ static int execute(const char *type, const char *device, const char *mntpt, if (noexecute) pid = -1; else if ((pid = fork()) < 0) { - perror("fork"); + perror("vfork"+1); return errno; } else if (pid == 0) { if (!interactive) diff --git a/include/libbb.h b/include/libbb.h index 4b6699f2f..e2a8322b8 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -841,6 +841,19 @@ int bb_execvp(const char *file, char *const argv[]) FAST_FUNC; #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 @@ int run_nofork_applet_prime(struct nofork_save_area *old, int applet_no, char ** * 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 @@ enum { 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 diff --git a/init/bootchartd.c b/init/bootchartd.c index 42b98c827..b3e08af92 100644 --- a/init/bootchartd.c +++ b/init/bootchartd.c @@ -427,9 +427,7 @@ int bootchartd_main(int argc UNUSED_PARAM, char **argv) } if (cmd == CMD_START && argv[2]) { /* "start PROG ARGS" */ - pid_t pid = vfork(); - if (pid < 0) - bb_perror_msg_and_die("vfork"); + pid_t pid = xvfork(); if (pid == 0) { /* child */ argv += 2; execvp(argv[0], argv); diff --git a/libbb/vfork_daemon_rexec.c b/libbb/vfork_daemon_rexec.c index 8102ea2dc..5c2c529c9 100644 --- a/libbb/vfork_daemon_rexec.c +++ b/libbb/vfork_daemon_rexec.c @@ -224,26 +224,12 @@ pid_t FAST_FUNC fork_or_rexec(char **argv) /* Maybe we are already re-execed and come here again? */ if (re_execed) return 0; - pid = vfork(); - if (pid < 0) /* wtf? */ - bb_perror_msg_and_die("vfork"); + pid = xvfork(); if (pid) /* parent */ return pid; /* child - re-exec ourself */ re_exec(argv); } -#else -/* Dance around (void)...*/ -#undef fork_or_rexec -pid_t FAST_FUNC fork_or_rexec(void) -{ - pid_t pid; - pid = fork(); - if (pid < 0) /* wtf? */ - bb_perror_msg_and_die("fork"); - return pid; -} -#define fork_or_rexec(argv) fork_or_rexec() #endif /* Due to a #define in libbb.h on MMU systems we actually have 1 argument - diff --git a/libbb/xfuncs_printf.c b/libbb/xfuncs_printf.c index f021493b1..7069a7c8e 100644 --- a/libbb/xfuncs_printf.c +++ b/libbb/xfuncs_printf.c @@ -589,3 +589,14 @@ void FAST_FUNC generate_uuid(uint8_t *buf) /* variant = 10x */ buf[4 + 2 + 2] = (buf[4 + 2 + 2] & 0x3f) | 0x80; } + +#if BB_MMU +pid_t FAST_FUNC xfork(void) +{ + pid_t pid; + pid = fork(); + if (pid < 0) /* wtf? */ + bb_perror_msg_and_die("vfork"+1); + return pid; +} +#endif diff --git a/mailutils/mail.c b/mailutils/mail.c index 5eb99e13d..bcd358302 100644 --- a/mailutils/mail.c +++ b/mailutils/mail.c @@ -54,9 +54,7 @@ void FAST_FUNC launch_helper(const char **argv) + (1 << SIGALRM) , signal_handler); - G.helper_pid = vfork(); - if (G.helper_pid < 0) - bb_perror_msg_and_die("vfork"); + G.helper_pid = xvfork(); i = (!G.helper_pid) * 2; // for parent:0, for child:2 close(pipes[i + 1]); // 1 or 3 - closing one write end diff --git a/miscutils/conspy.c b/miscutils/conspy.c index 3f341ce18..509a0f271 100644 --- a/miscutils/conspy.c +++ b/miscutils/conspy.c @@ -309,10 +309,7 @@ static void create_cdev_if_doesnt_exist(const char* name, dev_t dev) static NOINLINE void start_shell_in_child(const char* tty_name) { - int pid = vfork(); - if (pid < 0) { - bb_perror_msg_and_die("vfork"); - } + int pid = xvfork(); if (pid == 0) { struct termios termchild; char *shell = getenv("SHELL"); diff --git a/miscutils/crontab.c b/miscutils/crontab.c index 5557bc491..b8a5abc64 100644 --- a/miscutils/crontab.c +++ b/miscutils/crontab.c @@ -20,10 +20,8 @@ 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; @@ -51,9 +49,7 @@ 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 5cfbcef8e..9facc3657 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_ms(); - pid = vfork(); - if (pid < 0) - bb_perror_msg_and_die("vfork"); + pid = xvfork(); if (pid == 0) { /* Child */ BB_EXECVP_or_die((char**)cmd); diff --git a/miscutils/timeout.c b/miscutils/timeout.c index f6e655acc..48b8d8fc0 100644 --- a/miscutils/timeout.c +++ b/miscutils/timeout.c @@ -71,9 +71,7 @@ int timeout_main(int argc UNUSED_PARAM, char **argv) sv1 = argv[optind]; sv2 = argv[optind + 1]; #endif - pid = vfork(); - if (pid < 0) - bb_perror_msg_and_die("vfork"); + pid = xvfork(); if (pid == 0) { /* Child: spawn grandchild and exit */ parent = getppid(); diff --git a/networking/ftpd.c b/networking/ftpd.c index c63b9319e..e8cae0a36 100644 --- a/networking/ftpd.c +++ b/networking/ftpd.c @@ -632,10 +632,7 @@ popen_ls(const char *opt) xpiped_pair(outfd); /*fflush_all(); - so far we dont use stdio on output */ - pid = BB_MMU ? fork() : vfork(); - if (pid < 0) - bb_perror_msg_and_die(BB_MMU ? "fork" : "vfork"); - + pid = BB_MMU ? xfork() : xvfork(); if (pid == 0) { /* child */ #if !BB_MMU diff --git a/networking/ifupdown.c b/networking/ifupdown.c index 1bab2c5cb..69c56e879 100644 --- a/networking/ifupdown.c +++ b/networking/ifupdown.c @@ -1041,12 +1041,10 @@ static int popen2(FILE **in, FILE **out, char *command, char *param) xpiped_pair(outfd); fflush_all(); - 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/inetd.c b/networking/inetd.c index 2b0e0069e..7030062b6 100644 --- a/networking/inetd.c +++ b/networking/inetd.c @@ -1271,7 +1271,7 @@ int inetd_main(int argc UNUSED_PARAM, char **argv) pid = vfork(); if (pid < 0) { /* fork error */ - bb_perror_msg("fork"); + bb_perror_msg("vfork"+1); sleep(1); restore_sigmask(&omask); maybe_close(accepted_fd); diff --git a/networking/nc.c b/networking/nc.c index 5fd8bd759..0dacaf117 100644 --- a/networking/nc.c +++ b/networking/nc.c @@ -216,10 +216,8 @@ int nc_main(int argc, char **argv) if (execparam) { pid_t pid; /* With more than one -l, repeatedly act as server */ - if (do_listen > 1 && (pid = vfork()) != 0) { - /* parent or error */ - if (pid < 0) - bb_perror_msg_and_die("vfork"); + if (do_listen > 1 && (pid = xvfork()) != 0) { + /* parent */ /* prevent zombies */ signal(SIGCHLD, SIG_IGN); close(cfd); diff --git a/scripts/basic/docproc.c b/scripts/basic/docproc.c index ef5181226..50ef37157 100644 --- a/scripts/basic/docproc.c +++ b/scripts/basic/docproc.c @@ -86,7 +86,7 @@ void exec_kernel_doc(char **svec) fflush(stdout); switch(pid=fork()) { case -1: - perror("fork"); + perror("vfork"+1); exit(1); case 0: rflen = strlen(getenv("SRCTREE")); diff --git a/shell/hush.c b/shell/hush.c index 29ff3c442..831443e2e 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -3208,15 +3208,11 @@ static void setup_heredoc(struct redir_struct *redir) #if !BB_MMU to_free = NULL; #endif - pid = vfork(); - if (pid < 0) - bb_perror_msg_and_die("vfork"); + pid = xvfork(); if (pid == 0) { /* child */ disable_restore_tty_pgrp_on_exit(); - pid = BB_MMU ? fork() : vfork(); - if (pid < 0) - bb_perror_msg_and_die(BB_MMU ? "fork" : "vfork"); + pid = BB_MMU ? xfork() : xvfork(); if (pid != 0) _exit(0); /* grandchild */ @@ -4450,7 +4446,7 @@ static NOINLINE int run_pipe(struct pipe *pi) argv_expanded = NULL; if (command->pid < 0) { /* [v]fork failed */ /* Clearly indicate, was it fork or vfork */ - bb_perror_msg(BB_MMU ? "fork" : "vfork"); + bb_perror_msg(BB_MMU ? "vfork"+1 : "vfork"); } else { pi->alive_cmds++; #if ENABLE_HUSH_JOB @@ -5586,10 +5582,7 @@ static FILE *generate_stream_from_string(const char *s, pid_t *pid_p) # endif xpipe(channel); - pid = BB_MMU ? fork() : vfork(); - if (pid < 0) - bb_perror_msg_and_die(BB_MMU ? "fork" : "vfork"); - + pid = BB_MMU ? xfork() : xvfork(); if (pid == 0) { /* child */ disable_restore_tty_pgrp_on_exit(); /* Process substitution is not considered to be usual diff --git a/util-linux/script.c b/util-linux/script.c index d9a62fbfe..c23117cf3 100644 --- a/util-linux/script.c +++ b/util-linux/script.c @@ -88,10 +88,7 @@ int script_main(int argc UNUSED_PARAM, 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 */