From 63416cc57d5b2265952208425af377f252a7d0b4 Mon Sep 17 00:00:00 2001 From: Tomoya Adachi Date: Mon, 3 Aug 2009 02:59:22 +0200 Subject: nc: fix nc -ll; report vfork errors; make select loop faster function old new delta nc_main 933 946 +13 Signed-off-by: Tomoya Adachi Signed-off-by: Denys Vlasenko --- networking/nc.c | 43 +++++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 20 deletions(-) (limited to 'networking/nc.c') diff --git a/networking/nc.c b/networking/nc.c index e4db23895..243c47976 100644 --- a/networking/nc.c +++ b/networking/nc.c @@ -135,29 +135,27 @@ int nc_main(int argc, char **argv) /* -e given? */ if (execparam) { - signal(SIGCHLD, SIG_IGN); - // With more than one -l, repeatedly act as server. - if (do_listen > 1 && vfork()) { - /* parent */ - // This is a bit weird as cleanup goes, since we wind up with no - // stdin/stdout/stderr. But it's small and shouldn't hurt anything. - // We check for cfd == 0 above. - logmode = LOGMODE_NONE; - close(0); - close(1); - close(2); + 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"); + /* prevent zombies */ + signal(SIGCHLD, SIG_IGN); + close(cfd); goto accept_again; } - /* child (or main thread if no multiple -l) */ + /* child, or main thread if only one -l */ xmove_fd(cfd, 0); xdup2(0, 1); xdup2(0, 2); IF_NC_EXTRA(BB_EXECVP(execparam[0], execparam);) - /* Don't print stuff or it will go over the wire.... */ + /* Don't print stuff or it will go over the wire... */ _exit(127); } - // Select loop copying stdin to cfd, and cfd to stdout. + /* Select loop copying stdin to cfd, and cfd to stdout */ FD_ZERO(&readfds); FD_SET(cfd, &readfds); @@ -170,11 +168,12 @@ int nc_main(int argc, char **argv) testfds = readfds; - if (select(FD_SETSIZE, &testfds, NULL, NULL, NULL) < 0) + if (select(cfd + 1, &testfds, NULL, NULL, NULL) < 0) bb_perror_msg_and_die("select"); #define iobuf bb_common_bufsiz1 - for (fd = 0; fd < FD_SETSIZE; fd++) { + fd = STDIN_FILENO; + while (1) { if (FD_ISSET(fd, &testfds)) { nread = safe_read(fd, iobuf, sizeof(iobuf)); if (fd == cfd) { @@ -182,17 +181,21 @@ int nc_main(int argc, char **argv) exit(EXIT_SUCCESS); ofd = STDOUT_FILENO; } else { - if (nread<1) { - // Close outgoing half-connection so they get EOF, but - // leave incoming alone so we can see response. + if (nread < 1) { + /* Close outgoing half-connection so they get EOF, + * but leave incoming alone so we can see response */ shutdown(cfd, 1); FD_CLR(STDIN_FILENO, &readfds); } ofd = cfd; } xwrite(ofd, iobuf, nread); - if (delay > 0) sleep(delay); + if (delay > 0) + sleep(delay); } + if (fd == cfd) + break; + fd = cfd; } } } -- cgit v1.2.3