Print an optional packet count on stderr instead of printing packets

[tcpdump] / tcpdump.c

diff --git a/tcpdump.c b/tcpdump.c
index cd277042e3483e91d65b495b7633b2bdf09cb214..2f126391258578dfac27d5a983529b455e6f4f8b 100644 (file)
--- a/tcpdump.c
+++ b/tcpdump.c
@@ -220,6 +220,7 @@ static int timeout = 1000;          /* default timeout = 1000 ms = 1 s */
 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
 static int immediate_mode;
 #endif
+static int count_mode;
 
 static int infodelay;
 static int infoprint;
@@ -690,6 +691,7 @@ show_remote_devices_and_exit(void)
 #define OPTION_TSTAMP_MICRO            133
 #define OPTION_TSTAMP_NANO             134
 #define OPTION_FP_TYPE                 135
+#define OPTION_COUNT                   136
 
 static const struct option longopts[] = {
 #if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
@@ -733,6 +735,7 @@ static const struct option longopts[] = {
        { "debug-filter-parser", no_argument, NULL, 'Y' },
 #endif
        { "relinquish-privileges", required_argument, NULL, 'Z' },
+       { "count", no_argument, NULL, OPTION_COUNT },
        { "fp-type", no_argument, NULL, OPTION_FP_TYPE },
        { "number", no_argument, NULL, '#' },
        { "print", no_argument, NULL, OPTION_PRINT },
@@ -1908,6 +1911,10 @@ main(int argc, char **argv)
                        float_type_check(0x4e93312d);
                        return 0;
 
+               case OPTION_COUNT:
+                       count_mode = 1;
+                       break;
+
                default:
                        print_usage();
                        exit_tcpdump(S_ERR_HOST_PROGRAM);
@@ -2595,6 +2602,10 @@ DIAG_ON_CLANG(assign-enum)
        }
        while (ret != NULL);
 
+       if (count_mode && RFileName != NULL)
+               fprintf(stderr, "%u packet%s\n", packets_captured,
+                       PLURAL_SUFFIX(packets_captured));
+
        free(cmdbuf);
        pcap_freecode(&fcode);
        exit_tcpdump(status == -1 ? 1 : 0);
@@ -3027,7 +3038,8 @@ print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 
        ++infodelay;
 
-       pretty_print_packet((netdissect_options *)user, h, sp, packets_captured);
+       if (!count_mode)
+               pretty_print_packet((netdissect_options *)user, h, sp, packets_captured);
 
        --infodelay;
        if (infoprint)
@@ -3125,7 +3137,7 @@ print_usage(void)
 {
        print_version();
        (void)fprintf(stderr,
-"Usage: %s [-aAbd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqStu" U_FLAG "vxX#]" B_FLAG_USAGE " [ -c count ]\n", program_name);
+"Usage: %s [-aAbd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqStu" U_FLAG "vxX#]" B_FLAG_USAGE " [ -c count ] [--count]\n", program_name);
        (void)fprintf(stderr,
 "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
        (void)fprintf(stderr,