nc: exit when both stdin and network are closed.
function old new delta
nc_main 1051 1042 -9
readwrite 943 887 -56
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/nc_bloaty.c b/networking/nc_bloaty.c
index 00ba6f1..f01e862 100644
--- a/networking/nc_bloaty.c
+++ b/networking/nc_bloaty.c
@@ -48,6 +48,12 @@
* - TCP connects from wrong ip/ports (if peer ip:port is specified
* on the command line, but accept() says that it came from different addr)
* are closed, but we don't exit - we continue to listen/accept.
+ * Since bbox 1.22:
+ * - nc exits when _both_ stdin and network are closed.
+ * This makes these two commands:
+ * echo "Yes" | nc 127.0.0.1 1234
+ * echo "no" | nc -lp 1234
+ * exchange their data _and exit_ instead of being stuck.
*/
/* done in nc.c: #include "libbb.h" */
@@ -134,8 +140,6 @@
jmp_buf jbuf; /* timer crud */
- fd_set ding1; /* for select loop */
- fd_set ding2;
char bigbuf_in[BIGSIZ]; /* data buffers */
char bigbuf_net[BIGSIZ];
};
@@ -147,8 +151,6 @@
#define themaddr (G.themaddr )
#define remend (G.remend )
#define jbuf (G.jbuf )
-#define ding1 (G.ding1 )
-#define ding2 (G.ding2 )
#define bigbuf_in (G.bigbuf_in )
#define bigbuf_net (G.bigbuf_net)
#define o_verbose (G.o_verbose )
@@ -592,10 +594,17 @@
unsigned netretry; /* net-read retry counter */
unsigned wretry; /* net-write sanity counter */
unsigned wfirst; /* one-shot flag to skip first net read */
+ unsigned fds_open;
/* if you don't have all this FD_* macro hair in sys/types.h, you'll have to
either find it or do your own bit-bashing: *ding1 |= (1 << fd), etc... */
- FD_SET(netfd, &ding1); /* global: the net is open */
+ fd_set ding1; /* for select loop */
+ fd_set ding2;
+ FD_ZERO(&ding1);
+ FD_SET(netfd, &ding1);
+ FD_SET(STDIN_FILENO, &ding1);
+ fds_open = 2;
+
netretry = 2;
wfirst = 0;
rzleft = rnleft = 0;
@@ -604,7 +613,8 @@
errno = 0; /* clear from sleep, close, whatever */
/* and now the big ol' select shoveling loop ... */
- while (FD_ISSET(netfd, &ding1)) { /* i.e. till the *net* closes! */
+ /* nc 1.10 has "while (FD_ISSET(netfd)" here */
+ while (fds_open) {
wretry = 8200; /* more than we'll ever hafta write */
if (wfirst) { /* any saved stdin buffer? */
wfirst = 0; /* clear flag for the duration */
@@ -629,13 +639,14 @@
/* if we have a timeout AND stdin is closed AND we haven't heard anything
from the net during that time, assume it's dead and close it too. */
if (rr == 0) {
- if (!FD_ISSET(STDIN_FILENO, &ding1))
+ if (!FD_ISSET(STDIN_FILENO, &ding1)) {
netretry--; /* we actually try a coupla times. */
- if (!netretry) {
- if (o_verbose > 1) /* normally we don't care */
- fprintf(stderr, "net timeout\n");
- close(netfd);
- return 0; /* not an error! */
+ if (!netretry) {
+ if (o_verbose > 1) /* normally we don't care */
+ fprintf(stderr, "net timeout\n");
+ close(netfd);
+ return 0; /* not an error! */
+ }
}
} /* select timeout */
/* xxx: should we check the exception fds too? The read fds seem to give
@@ -649,7 +660,8 @@
/* nc 1.10 doesn't do this */
bb_perror_msg("net read");
}
- FD_CLR(netfd, &ding1); /* net closed, we'll finish up... */
+ FD_CLR(netfd, &ding1); /* net closed */
+ fds_open--;
rzleft = 0; /* can't write anymore: broken pipe */
} else {
rnleft = rr;
@@ -671,9 +683,10 @@
if (rr <= 0) { /* at end, or fukt, or ... */
FD_CLR(STDIN_FILENO, &ding1); /* disable and close stdin */
close(STDIN_FILENO);
-// Does it make sense to shutdown(net_fd, SHUT_WR)
-// to let other side know that we won't write anything anymore?
-// (and what about keeping compat if we do that?)
+ /* Let peer know we have no more data */
+ /* nc 1.10 doesn't do this: */
+ shutdown(netfd, SHUT_WR);
+ fds_open--;
} else {
rzleft = rr;
zp = bigbuf_in;
@@ -725,7 +738,7 @@
errno = 0; /* clear from sleep */
continue; /* ...with hairy select loop... */
}
- if ((rzleft) || (rnleft)) { /* shovel that shit till they ain't */
+ if (rzleft || rnleft) { /* shovel that shit till they ain't */
wretry--; /* none left, and get another load */
goto shovel;
}
@@ -876,9 +889,8 @@
}
#endif
- FD_SET(STDIN_FILENO, &ding1); /* stdin *is* initially open */
if (proggie) {
- close(0); /* won't need stdin */
+ close(STDIN_FILENO); /* won't need stdin */
option_mask32 &= ~OPT_o; /* -o with -e is meaningless! */
}
#if ENABLE_NC_EXTRA