Add support for FreeBSD.

Makefile.freebsd

@@ -0,0 +1,4 @@
+KMOD=	netcat
+SRCS=	netcat-freebsd.c
+
+.include <bsd.kmod.mk>

README.md

@@ -45,6 +45,17 @@ Other people report:
 * @ciderpunx can compile and run it on Debian 8.0 "Jessie" / Linux 3.12-1-amd64 #1 SMP Debian 3.12.9-1 (2014-02-01) x86_64 GNU/Linux
 * @f00stx slung some bits all the way from Brisbane, Australia to bring you a FreeBSD version (which he compiled on a G5 Mac, no less!) [Check it out here.](https://github.com/f00stx/netcat-cpi-kernel-module-bsd/tree/bsd)
 
+For FreeBSD:
+
+Just run:
+```
+
+make -f makefile.freebsd
+
+```
+
+For Linux:
+
 First, install some dependencies:
 
 ```
@@ -71,6 +82,15 @@ Listening
 
 After you build, you need to load the module and see if it is working, so you can run:
 
+For FreeBSD:
+
+```
+kldload ./netcat.ko
+dmesg
+```
+
+
+For Linux:
 ```
 sudo insmod netcat.ko
 dmesg
@@ -131,3 +151,4 @@ People insane enough to contribute (thanks!!)
 * @gregkh for making our module coherent with standard Linux style and cleaning up some other loose ends.
 * @silviuvulcan for testing with vlc and finding that we run and build on slackware64-current. Thanks!
 * @pah dropped some knowledge for anyone struggling in the streets with 32-bit kernels and vmalloc limits
+* Eitan Adler ported the module to FreeBSD -- more improvements including mmap() support and concurrent readers coming soon

netcat-freebsd.c

@@ -0,0 +1,148 @@
+#include <sys/param.h>
+#include <sys/module.h>
+#include <sys/kernel.h>
+#include <sys/systm.h>
+#include <sys/conf.h>   /* cdevsw struct */
+#include <sys/types.h>
+#include <sys/uio.h>
+
+#include "tracks/trk1.h"
+#include "tracks/trk2.h"
+#include "tracks/trk3.h"
+#include "tracks/trk4.h"
+#include "tracks/trk5.h"
+#include "tracks/trk6.h"
+
+/* Function prototypes */
+static d_open_t      netcat_open;
+static d_close_t     netcat_close;
+static d_read_t      netcat_read;
+
+static struct cdevsw netcat_cdevsw = {
+	.d_version = D_VERSION,
+	.d_open = netcat_open,
+	.d_close = netcat_close,
+	.d_read = netcat_read,
+	.d_name = "netcat",
+	.d_flags = D_DISK
+};
+
+static char *tracks[] = {netcat_cpi_trk1,
+                         netcat_cpi_trk2,
+                         netcat_cpi_trk3,
+                         netcat_cpi_trk4,
+                         netcat_cpi_trk5,
+                         netcat_cpi_trk6};
+
+static char *tracknames[] = {"Interrupt 0x7f",
+			 "The Internet is an Apt Motherfucker",
+			 "Interrupt 0x0d",
+			 "netcat",
+			 "Interrupt 0xbb",
+			 "Approximating the Circumference of the Earth"};
+
+static unsigned long tracklens[] = {NETCAT_CPI_TRK1_LEN,
+				    NETCAT_CPI_TRK2_LEN,
+				    NETCAT_CPI_TRK3_LEN,
+				    NETCAT_CPI_TRK4_LEN,
+				    NETCAT_CPI_TRK5_LEN,
+				    NETCAT_CPI_TRK6_LEN};
+
+static struct {
+	char	*msg;
+	int	current_track;
+	size_t	bytes;
+	bool	first;
+} netcatdata;
+
+static struct cdev *netcat_dev;
+
+static int netcat_loader(struct module *module, int event, void *arg) {
+	int e = 0;
+
+	switch (event) {
+		case MOD_LOAD:
+			uprintf("netcat - Cycles Per Instruction - Kernel Module Edition - 2014\n");
+			uprintf("netcat is Brandon Lucia, Andrew Olmstead, and David Balatero\n");
+			uprintf("On the web at http://netcat.co\n");
+			uprintf("'ogg123 - < /dev/netcat' to play.\n");
+			e = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK,
+				&netcat_dev,
+				&netcat_cdevsw,
+				0,
+				UID_ROOT,
+				GID_WHEEL,
+				0444,
+				"netcat");
+			if (e != 0)
+				break;
+
+			break;
+		case MOD_UNLOAD:
+			destroy_dev(netcat_dev);
+			break;
+
+		default:
+			e = EOPNOTSUPP;
+			break;
+	}
+
+	return (e);
+}
+
+static int netcat_open(struct cdev *dev __unused, int oflags __unused, int devtype __unused, struct thread *td __unused)
+{
+	int error = 0;
+
+	netcatdata.current_track = 0;
+	netcatdata.msg = tracks[netcatdata.current_track];        /* track 1 */
+	netcatdata.bytes = 0;
+	netcatdata.first = true;
+
+	return (error);
+}
+
+static int netcat_close(struct cdev *dev __unused, int oflags __unused, int devtype __unused, struct thread *td __unused)
+{
+	int error = 0;
+
+	return (error);
+}
+
+static int
+netcat_read(struct cdev *dev __unused, struct uio *uio, int ioflag __unused)
+{
+	int error = 0;
+	int totalbytesleft;
+
+	totalbytesleft = uio->uio_resid;
+
+	while (totalbytesleft > 0) {
+		if (netcatdata.first) {
+			uprintf("Now playing %s\n", tracknames[netcatdata.current_track]);
+			netcatdata.first = false;
+		}
+
+		int amt = MIN(totalbytesleft,
+			tracklens[netcatdata.current_track] - netcatdata.bytes);
+
+		error = uiomove(tracks[netcatdata.current_track] +
+			netcatdata.bytes, amt, uio);
+		if (error != 0)
+			return (error);
+
+		netcatdata.bytes += amt;
+		totalbytesleft -= amt;
+		if (netcatdata.bytes == tracklens[netcatdata.current_track]) {
+			netcatdata.bytes = 0;
+			netcatdata.first = true;
+			netcatdata.current_track = (netcatdata.current_track + 1) % nitems(tracks);
+		}
+
+	}
+
+	return (error);
+}
+
+DEV_MODULE(netcat, netcat_loader, NULL);
+