Avoid using a global variable when it's not needed

[tcpdump] / tcpdump.c

diff --git a/tcpdump.c b/tcpdump.c
index d5bf09bdef87bcd5d8bcb47c8d1aff5144b6d052..b76b426d691be1ceaf12862316a26772c9ba67ab 100644 (file)
--- a/tcpdump.c
+++ b/tcpdump.c
@@ -157,7 +157,7 @@ static int Jflag;                   /* list available time stamp types */
 static int jflag = -1;                 /* packet time stamp source */
 static int pflag;                      /* don't go promiscuous */
 #ifdef HAVE_PCAP_SETDIRECTION
-int Qflag = -1;                                /* restrict captured packet by send/receive direction */
+static int Qflag = -1;                 /* restrict captured packet by send/receive direction */
 #endif
 static int Uflag;                      /* "unbuffered" output of dump files */
 static int Wflag;                      /* recycle output files after this number of files */
@@ -187,8 +187,11 @@ static RETSIGTYPE cleanup(int);
 static RETSIGTYPE child_cleanup(int);
 static void print_version(void);
 static void print_usage(void);
-static void show_tstamp_types_and_exit(const char *device) __attribute__((noreturn));
-static void show_dlts_and_exit(const char *device) __attribute__((noreturn));
+static void show_tstamp_types_and_exit(pcap_t *, const char *device) __attribute__((noreturn));
+static void show_dlts_and_exit(pcap_t *, const char *device) __attribute__((noreturn));
+#ifdef HAVE_PCAP_FINDALLDEVS
+static void show_devices_and_exit (void) __attribute__((noreturn));
+#endif
 
 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
 static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
@@ -337,16 +340,16 @@ exit_tcpdump(int status)
 
 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
 static void
-show_tstamp_types_and_exit(const char *device)
+show_tstamp_types_and_exit(pcap_t *pc, const char *device)
 {
        int n_tstamp_types;
        int *tstamp_types = 0;
        const char *tstamp_type_name;
        int i;
 
-       n_tstamp_types = pcap_list_tstamp_types(pd, &tstamp_types);
+       n_tstamp_types = pcap_list_tstamp_types(pc, &tstamp_types);
        if (n_tstamp_types < 0)
-               error("%s", pcap_geterr(pd));
+               error("%s", pcap_geterr(pc));
 
        if (n_tstamp_types == 0) {
                fprintf(stderr, "Time stamp type cannot be set for %s\n",
@@ -370,15 +373,15 @@ show_tstamp_types_and_exit(const char *device)
 #endif
 
 static void
-show_dlts_and_exit(const char *device)
+show_dlts_and_exit(pcap_t *pc, const char *device)
 {
        int n_dlts, i;
        int *dlts = 0;
        const char *dlt_name;
 
-       n_dlts = pcap_list_datalinks(pd, &dlts);
+       n_dlts = pcap_list_datalinks(pc, &dlts);
        if (n_dlts < 0)
-               error("%s", pcap_geterr(pd));
+               error("%s", pcap_geterr(pc));
        else if (n_dlts == 0 || !dlts)
                error("No data link types.");
 
@@ -828,7 +831,7 @@ copy_argv(register char **argv)
        char *src, *dst;
 
        p = argv;
-       if (*p == 0)
+       if (*p == NULL)
                return 0;
 
        while (*p)
@@ -971,7 +974,7 @@ open_interface(const char *device, netdissect_options *ndo, char *ebuf)
        }
 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
        if (Jflag)
-               show_tstamp_types_and_exit(device);
+               show_tstamp_types_and_exit(pc, device);
 #endif
 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
        status = pcap_set_tstamp_precision(pc, ndo->ndo_tstamp_precision);
@@ -1726,7 +1729,7 @@ main(int argc, char **argv)
                        }
 #endif /* !defined(HAVE_PCAP_CREATE) && defined(_WIN32) */
                if (Lflag)
-                       show_dlts_and_exit(device);
+                       show_dlts_and_exit(pd, device);
                if (yflag_dlt >= 0) {
 #ifdef HAVE_PCAP_SET_DATALINK
                        if (pcap_set_datalink(pd, yflag_dlt) < 0)