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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 | 38 +++++++++++++++++++++++++++++++++-----
2 files changed, 38 insertions(+), 5 deletions(-)
diff --git a/nc.1 b/nc.1
index af44976..0d92b74 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
@@ -148,6 +149,10 @@ 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 seconds and then quit. If
+.Ar seconds
+is negative, wait forever.
.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 4f4d2bf..29ecf1a 100644
--- a/netcat.c
+++ b/netcat.c
@@ -86,6 +86,7 @@
#include <errno.h>
#include <netdb.h>
#include <poll.h>
+#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
@@ -120,6 +121,7 @@ int lflag; /* Bind to local port */
int nflag; /* Don't do name look up */
char *Pflag; /* Proxy username */
char *pflag; /* Localport flag */
+int qflag = 0; /* Quit after some secs */
int rflag; /* Random ports flag */
char *sflag; /* Source Address */
int tflag; /* Telnet Emulation */
@@ -158,6 +160,7 @@ void usage(int);
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[])
@@ -181,7 +184,7 @@ main(int argc, char *argv[])
sv = NULL;
while ((ch = getopt(argc, argv,
- "46CDdhI:i:jklnO:P:p:rSs:tT:UuV:vw:X:x:z")) != -1) {
+ "46CDdhI:i:jklnO:P:p:q:rSs:tT:UuV:vw:X:x:z")) != -1) {
switch (ch) {
case '4':
family = AF_INET;
@@ -235,6 +238,11 @@ 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);
+ break;
case 'r':
rflag = 1;
break;
@@ -924,9 +932,18 @@ readwrite(int nfd)
}
else if (pfd[1].revents & POLLHUP) {
shutdown_wr:
+ /* if the user asked to exit on EOF, do it */
+ if (qflag == 0) {
shutdown(nfd, SHUT_WR);
- pfd[1].fd = -1;
- pfd[1].events = 0;
+ close(wfd);
+ }
+ /* if user asked to die after a while, arrange for it */
+ if (qflag > 0) {
+ signal(SIGALRM, quit);
+ alarm(qflag);
+ }
+ pfd[1].fd = -1;
+ pfd[1].events = 0;
}
}
}
@@ -1164,6 +1181,7 @@ 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\
@@ -1186,9 +1204,19 @@ usage(int ret)
{
fprintf(stderr,
"usage: nc [-46CDdhjklnrStUuvz] [-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()
+{
+ /* XXX: should explicitly close fds here */
+ exit(0);
+}
--
|
