add pcap_{get,set}nonblock, to work around BPF b0rkage on OS X, FreeB…

…SD, etc.

pcap.pyx

@@ -63,11 +63,13 @@ cdef extern from "pcap.h":
 
 cdef extern from "pcap_ex.h":
     # XXX - hrr, sync with libdnet and libevent
-    void    pcap_ex_immediate(pcap_t *p)
+    int     pcap_ex_immediate(pcap_t *p)
     char   *pcap_ex_name(char *name)
     char   *pcap_ex_lookupdev(char *ebuf)
     int     pcap_ex_fileno(pcap_t *p)
     void    pcap_ex_setup(pcap_t *p)
+    void    pcap_ex_setnonblock(pcap_t *p, int nonblock, char *ebuf)
+    int     pcap_ex_getnonblock(pcap_t *p, char *ebuf)
     int     pcap_ex_next(pcap_t *p, pcap_pkthdr **hdr, char **pkt)
     int     pcap_ex_compile_nopcap(int snaplen, int dlt,
                                    bpf_program *fp, char *str,
@@ -163,7 +165,7 @@ cdef class pcap:
         if not name:
             p = pcap_ex_lookupdev(self.__ebuf)
             if p == NULL:
-                raise OSError, "couldn't lookup device"
+                raise OSError, self.__ebuf
         else:
             p = name
 
@@ -178,8 +180,8 @@ cdef class pcap:
         self.__filter = strdup("")
         try: self.__dloff = dltoff[pcap_datalink(self.__pcap)]
         except KeyError: pass
-        if immediate:
-            pcap_ex_immediate(self.__pcap)
+        if immediate and pcap_ex_immediate(self.__pcap) < 0:
+            raise OSError, "couldn't set BPF immediate mode"
 
     property name:
         """Network interface or dumpfile name."""
@@ -220,6 +222,19 @@ cdef class pcap:
         if pcap_setfilter(self.__pcap, &fcode) < 0:
             raise OSError, pcap_geterr(self.__pcap)
         pcap_freecode(&fcode)
+
+    def setnonblock(self, nonblock=True):
+        """Set non-blocking capture mode."""
+        pcap_ex_setnonblock(self.__pcap, nonblock, self.__ebuf)
+
+    def getnonblock(self):
+        """Return non-blocking capture mode as boolean."""
+        ret = pcap_ex_getnonblock(self.__pcap, self.__ebuf)
+        if ret < 0:
+            raise OSError, self.__ebuf
+        elif ret:
+            return True
+        return False
 
     def datalink(self):
         """Return datalink type (DLT_* values)."""

pcap_ex.c

@@ -28,11 +28,15 @@ int    PyGILState_Ensure() { return (0); }
 void   PyGILState_Release(int gil) { }
 #endif
 
-void
+int
 pcap_ex_immediate(pcap_t *pcap)
 {
 #ifdef BIOCIMMEDIATE
-	ioctl(pcap_fileno(pcap), BIOCIMMEDIATE, 1);
+	int n = 1;
+
+	return ioctl(pcap_fileno(pcap), BIOCIMMEDIATE, &n);
+#else
+	return (0);
 #endif
 }
 
@@ -196,16 +200,35 @@ pcap_ex_setup(pcap_t *pcap)
 #ifdef _WIN32
 	SetConsoleCtrlHandler(__pcap_ex_ctrl, TRUE);
 #else
+#if 0
 	int fd, n;
 
 	fd = pcap_fileno(pcap);
 	n = fcntl(fd, F_GETFL, 0) | O_NONBLOCK;
 	fcntl(fd, F_SETFL, n);
-
+#endif
 	signal(SIGINT, __pcap_ex_signal);
 #endif
 }
 
+void
+pcap_ex_setnonblock(pcap_t *pcap, int nonblock, char *ebuf)
+{
+#ifdef HAVE_PCAP_SETNONBLOCK
+	pcap_setnonblock(pcap, nonblock, ebuf);
+#endif
+}
+
+int
+pcap_ex_getnonblock(pcap_t *pcap, char *ebuf)
+{
+#ifdef HAVE_PCAP_SETNONBLOCK
+	return (pcap_getnonblock(pcap, ebuf));
+#else
+	return (0);
+#endif
+}
+
 /* return codes: 1 = pkt, 0 = timeout, -1 = error, -2 = EOF */
 int
 pcap_ex_next(pcap_t *pcap, struct pcap_pkthdr **hdr, u_char **pkt)

pcap_ex.h

@@ -3,11 +3,13 @@
 #ifndef PCAP_EX_H
 #define PCAP_EX_H
 
-void  pcap_ex_immediate(pcap_t *pcap);
+int   pcap_ex_immediate(pcap_t *pcap);
 char *pcap_ex_name(char *name);
 char *pcap_ex_lookupdev(char *ebuf);
 int   pcap_ex_fileno(pcap_t *pcap);
 void  pcap_ex_setup(pcap_t *pcap);
+void  pcap_ex_setnonblock(pcap_t *pcap, int nonblock, char *ebuf);
+int   pcap_ex_getnonblock(pcap_t *pcap, char *ebuf);
 int   pcap_ex_next(pcap_t *pcap, struct pcap_pkthdr **hdr, u_char **pkt);
 int   pcap_ex_compile_nopcap(int snaplen, int dlt, struct bpf_program *fp,
           char *str, int optimize, unsigned int netmask);

setup.py

@@ -30,6 +30,8 @@ def _write_config_h(self, cfg):
             d['HAVE_PCAP_FILE'] = 1
         if buf.find('pcap_compile_nopcap(') != -1:
             d['HAVE_PCAP_COMPILE_NOPCAP'] = 1
+        if buf.find('pcap_setnonblock(') != -1:
+            d['HAVE_PCAP_SETNONBLOCK'] = 1
         f = open('config.h', 'w')
         for k, v in d.iteritems():
             f.write('#define %s %s\n' % (k, v))
@@ -90,7 +92,7 @@ def run(self):
 pcap_cmds = { 'config':config_pcap, 'clean':clean_pcap }
 
 setup(name='pcap',
-      version='0.6',
+      version='1.0',
       author='Dug Song',
       author_email='dugsong@monkey.org',
       url='http://monkey.org/~dugsong/pypcap/',