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From: Aron Xu <aron@debian.org>
Date: Mon, 13 Feb 2012 15:16:04 +0800
Subject: quit timer
---
nc.1 | 5 +++++
netcat.c | 52 +++++++++++++++++++++++++++++++++++++++++++---------
2 files changed, 48 insertions(+), 9 deletions(-)
diff --git a/nc.1 b/nc.1
index 746d3b6..1ee6887 100644
--- a/nc.1
+++ b/nc.1
@@ -40,6 +40,7 @@
.Op Fl O Ar length
.Op Fl P Ar proxy_username
.Op Fl p Ar source_port
+.Op Fl q Ar seconds
.Op Fl s Ar source
.Op Fl T Ar toskeyword
.Op Fl V Ar rtable
@@ -171,6 +172,15 @@ Proxy authentication is only supported for HTTP CONNECT proxies at present.
Specifies the source port
.Nm
should use, subject to privilege restrictions and availability.
+.It Fl q Ar seconds
+after EOF on stdin, wait the specified number of
+.Ar seconds
+and then quit. If
+.Ar seconds
+is negative, wait forever (default). Specifying a non-negative
+.Ar seconds
+implies
+.Fl N .
.It Fl r
Specifies that source and/or destination ports should be chosen randomly
instead of sequentially within a range or in the order that the system
diff --git a/netcat.c b/netcat.c
index 1c90145..7572bb2 100644
--- a/netcat.c
+++ b/netcat.c
@@ -128,6 +128,7 @@ int Nflag; /* shutdown() network socket */
int nflag; /* Don't do name look up */
char *Pflag; /* Proxy username */
char *pflag; /* Localport flag */
+int qflag = -1; /* Quit after some secs */
int rflag; /* Random ports flag */
char *sflag; /* Source Address */
int tflag; /* Telnet Emulation */
@@ -171,6 +172,8 @@ ssize_t fillbuf(int, unsigned char *, size_t *);
static int connect_with_timeout(int fd, const struct sockaddr *sa,
socklen_t salen, int ctimeout);
+static void quit();
+
int
main(int argc, char *argv[])
{
@@ -195,7 +198,7 @@ main(int argc, char *argv[])
signal(SIGPIPE, SIG_IGN);
while ((ch = getopt(argc, argv,
- "46CDdFhI:i:klNnO:P:p:rSs:tT:UuV:vw:X:x:z")) != -1) {
+ "46CDdFhI:i:klNnO:P:p:q:rSs:tT:UuV:vw:X:x:z")) != -1) {
switch (ch) {
case '4':
family = AF_INET;
@@ -248,6 +251,13 @@ main(int argc, char *argv[])
case 'p':
pflag = optarg;
break;
+ case 'q':
+ qflag = strtonum(optarg, INT_MIN, INT_MAX, &errstr);
+ if (errstr)
+ errx(1, "quit timer %s: %s", errstr, optarg);
+ if (qflag >= 0)
+ Nflag = 1;
+ break;
case 'r':
rflag = 1;
break;
@@ -918,18 +928,26 @@ readwrite(int net_fd)
if (pfd[POLL_STDIN].fd == -1 && pfd[POLL_NETIN].fd == -1
&& stdinbufpos == 0 && netinbufpos == 0) {
close(net_fd);
- return;
+ if (qflag <= 0)
+ return;
+ goto delay_exit;
}
/* both outputs are gone, we can't continue */
if (pfd[POLL_NETOUT].fd == -1 && pfd[POLL_STDOUT].fd == -1) {
close(net_fd);
- return;
+ if (qflag <= 0)
+ return;
+ goto delay_exit;
}
/* listen and net in gone, queues empty, done */
if (lflag && pfd[POLL_NETIN].fd == -1
&& stdinbufpos == 0 && netinbufpos == 0) {
close(net_fd);
- return;
+ if (qflag <= 0)
+ return;
+delay_exit:
+ signal(SIGALRM, quit);
+ alarm(qflag);
}
/* poll */
@@ -1436,6 +1454,7 @@ help(void)
\t-O length TCP send buffer length\n\
\t-P proxyuser\tUsername for proxy authentication\n\
\t-p port\t Specify local port for remote connects\n\
+ \t-q secs\t quit after EOF on stdin and delay of secs\n\
\t-r Randomize remote ports\n\
\t-S Enable the TCP MD5 signature option\n\
\t-s addr\t Local source address\n\
@@ -1458,9 +1477,18 @@ usage(int ret)
{
fprintf(stderr,
"usage: nc [-46CDdFhklNnrStUuvz] [-I length] [-i interval] [-O length]\n"
- "\t [-P proxy_username] [-p source_port] [-s source] [-T toskeyword]\n"
- "\t [-V rtable] [-w timeout] [-X proxy_protocol]\n"
+ "\t [-P proxy_username] [-p source_port] [-q seconds] [-s source]\n"
+ "\t [-T toskeyword] [-V rtable] [-w timeout] [-X proxy_protocol]\n"
"\t [-x proxy_address[:port]] [destination] [port]\n");
if (ret)
exit(1);
}
+
+/*
+ * quit()
+ * handler for a "-q" timeout (exit 0 instead of 1)
+ */
+static void quit()
+{
+ exit(0);
+}
|
