2 * Routines for capture options setting
6 * Wireshark - Network traffic analyzer
7 * By Gerald Combs <gerald@wireshark.org>
8 * Copyright 1998 Gerald Combs
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version 2
13 * of the License, or (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
38 #ifdef HAVE_SYS_TYPES_H
39 # include <sys/types.h>
42 #ifdef HAVE_NETINET_IN_H
43 #include <netinet/in.h>
46 #ifdef HAVE_ARPA_INET_H
47 #include <arpa/inet.h>
50 #ifdef HAVE_SYS_SOCKET_H
51 #include <sys/socket.h> /* needed to define AF_ values on UNIX */
54 #ifdef HAVE_WINSOCK2_H
55 #include <winsock2.h> /* needed to define AF_ values on Windows */
58 #ifdef NEED_INET_V6DEFS_H
59 # include "inet_v6defs.h"
64 #include <epan/packet.h>
66 #include "capture_opts.h"
67 #include "ringbuffer.h"
68 #include "clopts_common.h"
69 #include "cmdarg_err.h"
71 #include "capture-pcap-util.h"
72 #include <wiretap/file_util.h>
79 static gboolean capture_opts_output_to_pipe(const char *save_file, gboolean *is_pipe);
83 capture_opts_init(capture_options *capture_opts, void *cfile)
85 capture_opts->cf = cfile;
86 capture_opts->cfilter = g_strdup(""); /* No capture filter string specified */
87 capture_opts->iface = NULL; /* Default is "pick the first interface" */
88 capture_opts->iface_descr = NULL;
89 #ifdef HAVE_PCAP_REMOTE
90 capture_opts->src_type = CAPTURE_IFLOCAL;
91 capture_opts->remote_host = NULL;
92 capture_opts->remote_port = NULL;
93 capture_opts->auth_type = CAPTURE_AUTH_NULL;
94 capture_opts->auth_username = NULL;
95 capture_opts->auth_password = NULL;
96 capture_opts->datatx_udp = FALSE;
97 capture_opts->nocap_rpcap = TRUE;
98 capture_opts->nocap_local = FALSE;
99 #ifdef HAVE_PCAP_SETSAMPLING
100 capture_opts->sampling_method = CAPTURE_SAMP_NONE;
101 capture_opts->sampling_param = 0;
105 capture_opts->buffer_size = 1; /* 1 MB */
107 capture_opts->has_snaplen = FALSE;
108 capture_opts->snaplen = WTAP_MAX_PACKET_SIZE; /* snapshot length - default is
109 infinite, in effect */
110 capture_opts->promisc_mode = TRUE; /* promiscuous mode is the default */
111 capture_opts->linktype = -1; /* the default linktype */
112 capture_opts->saving_to_file = FALSE;
113 capture_opts->save_file = NULL;
114 capture_opts->real_time_mode = TRUE;
115 capture_opts->show_info = TRUE;
116 capture_opts->quit_after_cap = FALSE;
117 capture_opts->restart = FALSE;
119 capture_opts->multi_files_on = FALSE;
120 capture_opts->has_file_duration = FALSE;
121 capture_opts->file_duration = 60; /* 1 min */
122 capture_opts->has_ring_num_files = FALSE;
123 capture_opts->ring_num_files = RINGBUFFER_MIN_NUM_FILES;
125 capture_opts->has_autostop_files = FALSE;
126 capture_opts->autostop_files = 1;
127 capture_opts->has_autostop_packets = FALSE;
128 capture_opts->autostop_packets = 0;
129 capture_opts->has_autostop_filesize = FALSE;
130 capture_opts->autostop_filesize = 1024; /* 1 MB */
131 capture_opts->has_autostop_duration = FALSE;
132 capture_opts->autostop_duration = 60; /* 1 min */
135 capture_opts->fork_child = -1; /* invalid process handle */
137 capture_opts->signal_pipe_write_fd = -1;
139 capture_opts->state = CAPTURE_STOPPED;
140 capture_opts->output_to_pipe = FALSE;
142 capture_opts->owner = getuid();
143 capture_opts->group = getgid();
148 /* log content of capture_opts */
150 capture_opts_log(const char *log_domain, GLogLevelFlags log_level, capture_options *capture_opts) {
151 g_log(log_domain, log_level, "CAPTURE OPTIONS :");
152 g_log(log_domain, log_level, "CFile : 0x%p", capture_opts->cf);
153 g_log(log_domain, log_level, "Filter : %s", capture_opts->cfilter);
154 g_log(log_domain, log_level, "Interface : %s", capture_opts->iface);
155 /* iface_descr may not been filled in and some C Libraries hate a null ptr for %s */
156 g_log(log_domain, log_level, "Interface Descr : %s",
157 capture_opts->iface_descr ? capture_opts->iface_descr : "<null>");
158 #ifdef HAVE_PCAP_REMOTE
159 g_log(log_domain, log_level, "Capture source : %s",
160 capture_opts->src_type == CAPTURE_IFLOCAL ? "Local interface" :
161 capture_opts->src_type == CAPTURE_IFREMOTE ? "Remote interface" :
163 if (capture_opts->src_type == CAPTURE_IFREMOTE) {
164 g_log(log_domain, log_level, "Remote host : %s", capture_opts->remote_host);
165 g_log(log_domain, log_level, "Remote port : %u", capture_opts->remote_port);
167 g_log(log_domain, log_level, "Authentication : %s",
168 capture_opts->auth_type == CAPTURE_AUTH_NULL ? "Null" :
169 capture_opts->auth_type == CAPTURE_AUTH_PWD ? "By username/password" :
171 if (capture_opts->auth_type == CAPTURE_AUTH_PWD) {
172 g_log(log_domain, log_level, "Auth username : %s", capture_opts->auth_password);
173 g_log(log_domain, log_level, "Auth password : <hidden>");
175 g_log(log_domain, log_level, "UDP data transfer : %u", capture_opts->datatx_udp);
176 g_log(log_domain, log_level, "No capture RPCAP : %u", capture_opts->nocap_rpcap);
177 g_log(log_domain, log_level, "No capture local : %u", capture_opts->nocap_local);
180 g_log(log_domain, log_level, "BufferSize : %u (MB)", capture_opts->buffer_size);
182 g_log(log_domain, log_level, "SnapLen (%u): %u", capture_opts->has_snaplen, capture_opts->snaplen);
183 g_log(log_domain, log_level, "Promisc : %u", capture_opts->promisc_mode);
184 g_log(log_domain, log_level, "LinkType : %d", capture_opts->linktype);
185 g_log(log_domain, log_level, "SavingToFile : %u", capture_opts->saving_to_file);
186 g_log(log_domain, log_level, "SaveFile : %s", (capture_opts->save_file) ? capture_opts->save_file : "");
187 g_log(log_domain, log_level, "RealTimeMode : %u", capture_opts->real_time_mode);
188 g_log(log_domain, log_level, "ShowInfo : %u", capture_opts->show_info);
189 g_log(log_domain, log_level, "QuitAfterCap : %u", capture_opts->quit_after_cap);
191 g_log(log_domain, log_level, "MultiFilesOn : %u", capture_opts->multi_files_on);
192 g_log(log_domain, log_level, "FileDuration (%u): %u", capture_opts->has_file_duration, capture_opts->file_duration);
193 g_log(log_domain, log_level, "RingNumFiles (%u): %u", capture_opts->has_ring_num_files, capture_opts->ring_num_files);
195 g_log(log_domain, log_level, "AutostopFiles (%u): %u", capture_opts->has_autostop_files, capture_opts->autostop_files);
196 g_log(log_domain, log_level, "AutostopPackets (%u): %u", capture_opts->has_autostop_packets, capture_opts->autostop_packets);
197 g_log(log_domain, log_level, "AutostopFilesize(%u): %u (KB)", capture_opts->has_autostop_filesize, capture_opts->autostop_filesize);
198 g_log(log_domain, log_level, "AutostopDuration(%u): %u", capture_opts->has_autostop_duration, capture_opts->autostop_duration);
200 g_log(log_domain, log_level, "ForkChild : %d", capture_opts->fork_child);
202 g_log(log_domain, log_level, "SignalPipeWrite : %d", capture_opts->signal_pipe_write_fd);
207 * Given a string of the form "<autostop criterion>:<value>", as might appear
208 * as an argument to a "-a" option, parse it and set the criterion in
209 * question. Return an indication of whether it succeeded or failed
213 set_autostop_criterion(capture_options *capture_opts, const char *autostoparg)
217 colonp = strchr(autostoparg, ':');
225 * Skip over any white space (there probably won't be any, but
226 * as we allow it in the preferences file, we might as well
229 while (isspace((guchar)*p))
233 * Put the colon back, so if our caller uses, in an
234 * error message, the string they passed us, the message
240 if (strcmp(autostoparg,"duration") == 0) {
241 capture_opts->has_autostop_duration = TRUE;
242 capture_opts->autostop_duration = get_positive_int(p,"autostop duration");
243 } else if (strcmp(autostoparg,"filesize") == 0) {
244 capture_opts->has_autostop_filesize = TRUE;
245 capture_opts->autostop_filesize = get_positive_int(p,"autostop filesize");
246 } else if (strcmp(autostoparg,"files") == 0) {
247 capture_opts->multi_files_on = TRUE;
248 capture_opts->has_autostop_files = TRUE;
249 capture_opts->autostop_files = get_positive_int(p,"autostop files");
253 *colonp = ':'; /* put the colon back */
258 * Given a string of the form "<ring buffer file>:<duration>", as might appear
259 * as an argument to a "-b" option, parse it and set the arguments in
260 * question. Return an indication of whether it succeeded or failed
264 get_ring_arguments(capture_options *capture_opts, const char *arg)
266 gchar *p = NULL, *colonp;
268 colonp = strchr(arg, ':');
276 * Skip over any white space (there probably won't be any, but
277 * as we allow it in the preferences file, we might as well
280 while (isspace((guchar)*p))
284 * Put the colon back, so if our caller uses, in an
285 * error message, the string they passed us, the message
292 if (strcmp(arg,"files") == 0) {
293 capture_opts->has_ring_num_files = TRUE;
294 capture_opts->ring_num_files = get_natural_int(p, "number of ring buffer files");
295 } else if (strcmp(arg,"filesize") == 0) {
296 capture_opts->has_autostop_filesize = TRUE;
297 capture_opts->autostop_filesize = get_positive_int(p, "ring buffer filesize");
298 } else if (strcmp(arg,"duration") == 0) {
299 capture_opts->has_file_duration = TRUE;
300 capture_opts->file_duration = get_positive_int(p, "ring buffer duration");
303 *colonp = ':'; /* put the colon back */
307 #ifdef HAVE_PCAP_SETSAMPLING
309 * Given a string of the form "<sampling type>:<value>", as might appear
310 * as an argument to a "-m" option, parse it and set the arguments in
311 * question. Return an indication of whether it succeeded or failed
315 get_sampling_arguments(capture_options *capture_opts, const char *arg)
317 gchar *p = NULL, *colonp;
319 colonp = strchr(arg, ':');
326 while (isspace((guchar)*p))
333 if (strcmp(arg, "count") == 0) {
334 capture_opts->sampling_method = CAPTURE_SAMP_BY_COUNT;
335 capture_opts->sampling_param = get_positive_int(p, "sampling count");
336 } else if (strcmp(arg, "timer") == 0) {
337 capture_opts->sampling_method = CAPTURE_SAMP_BY_TIMER;
338 capture_opts->sampling_param = get_positive_int(p, "sampling timer");
345 #ifdef HAVE_PCAP_REMOTE
347 * Given a string of the form "<username>:<password>", as might appear
348 * as an argument to a "-A" option, parse it and set the arguments in
349 * question. Return an indication of whether it succeeded or failed
353 get_auth_arguments(capture_options *capture_opts, const char *arg)
355 gchar *p = NULL, *colonp;
357 colonp = strchr(arg, ':');
364 while (isspace((guchar)*p))
367 capture_opts->auth_type = CAPTURE_AUTH_PWD;
368 capture_opts->auth_username = g_strdup(arg);
369 capture_opts->auth_password = g_strdup(p);
376 capture_opts_add_iface_opt(capture_options *capture_opts, const char *optarg)
387 * If the argument is a number, treat it as an index into the list
388 * of adapters, as printed by "tshark -D".
390 * This should be OK on UNIX systems, as interfaces shouldn't have
391 * names that begin with digits. It can be useful on Windows, where
392 * more than one interface can have the same name.
394 adapter_index = strtol(optarg, &p, 10);
395 if (p != NULL && *p == '\0') {
396 if (adapter_index < 0) {
397 cmdarg_err("The specified adapter index is a negative number");
400 if (adapter_index > INT_MAX) {
401 cmdarg_err("The specified adapter index is too large (greater than %d)",
405 if (adapter_index == 0) {
406 cmdarg_err("There is no interface with that adapter index");
409 if_list = get_interface_list(&err, &err_str);
410 if (if_list == NULL) {
413 case CANT_GET_INTERFACE_LIST:
414 cmdarg_err("%s", err_str);
418 case NO_INTERFACES_FOUND:
419 cmdarg_err("There are no interfaces on which a capture can be done");
424 if_info = g_list_nth_data(if_list, adapter_index - 1);
425 if (if_info == NULL) {
426 cmdarg_err("There is no interface with that adapter index");
429 capture_opts->iface = g_strdup(if_info->name);
430 /* We don't set iface_descr here because doing so requires
431 * capture_ui_utils.c which requires epan/prefs.c which is
432 * probably a bit too much dependency for here...
434 free_interface_list(if_list);
436 capture_opts->iface = g_strdup(optarg);
443 capture_opts_add_opt(capture_options *capture_opts, int opt, const char *optarg, gboolean *start_capture)
448 case 'a': /* autostop criteria */
449 if (set_autostop_criterion(capture_opts, optarg) == FALSE) {
450 cmdarg_err("Invalid or unknown -a flag \"%s\"", optarg);
454 #ifdef HAVE_PCAP_REMOTE
456 if (get_auth_arguments(capture_opts, optarg) == FALSE) {
457 cmdarg_err("Invalid or unknown -A arg \"%s\"", optarg);
462 case 'b': /* Ringbuffer option */
463 capture_opts->multi_files_on = TRUE;
464 if (get_ring_arguments(capture_opts, optarg) == FALSE) {
465 cmdarg_err("Invalid or unknown -b arg \"%s\"", optarg);
470 case 'B': /* Buffer size */
471 capture_opts->buffer_size = get_positive_int(optarg, "buffer size");
474 case 'c': /* Capture n packets */
475 capture_opts->has_autostop_packets = TRUE;
476 capture_opts->autostop_packets = get_positive_int(optarg, "packet count");
478 case 'f': /* capture filter */
479 if (capture_opts->has_cfilter) {
480 cmdarg_err("More than one -f argument specified");
483 capture_opts->has_cfilter = TRUE;
484 g_free(capture_opts->cfilter);
485 capture_opts->cfilter = g_strdup(optarg);
487 case 'H': /* Hide capture info dialog box */
488 capture_opts->show_info = FALSE;
490 case 'i': /* Use interface x */
491 status = capture_opts_add_iface_opt(capture_opts, optarg);
496 case 'k': /* Start capture immediately */
497 *start_capture = TRUE;
499 /*case 'l':*/ /* Automatic scrolling in live capture mode */
500 #ifdef HAVE_PCAP_SETSAMPLING
502 if (get_sampling_arguments(capture_opts, optarg) == FALSE) {
503 cmdarg_err("Invalid or unknown -m arg \"%s\"", optarg);
508 case 'p': /* Don't capture in promiscuous mode */
509 capture_opts->promisc_mode = FALSE;
511 case 'Q': /* Quit after capture (just capture to file) */
512 capture_opts->quit_after_cap = TRUE;
513 *start_capture = TRUE; /*** -Q implies -k !! ***/
515 #ifdef HAVE_PCAP_REMOTE
517 capture_opts->nocap_rpcap = FALSE;
520 case 's': /* Set the snapshot (capture) length */
521 capture_opts->has_snaplen = TRUE;
522 capture_opts->snaplen = get_positive_int(optarg, "snapshot length");
524 case 'S': /* "Real-Time" mode: used for following file ala tail -f */
525 capture_opts->real_time_mode = TRUE;
527 #ifdef HAVE_PCAP_REMOTE
529 capture_opts->datatx_udp = TRUE;
532 case 'w': /* Write to capture file x */
533 capture_opts->saving_to_file = TRUE;
534 g_free(capture_opts->save_file);
535 #if defined _WIN32 && (GLIB_MAJOR_VERSION > 2 || (GLIB_MAJOR_VERSION == 2 && GLIB_MINOR_VERSION >= 6))
536 /* since GLib 2.6, we need to convert filenames to utf8 for Win32 */
537 capture_opts->save_file = g_locale_to_utf8(optarg, -1, NULL, NULL, NULL);
539 capture_opts->save_file = g_strdup(optarg);
541 status = capture_opts_output_to_pipe(capture_opts->save_file, &capture_opts->output_to_pipe);
544 case 'y': /* Set the pcap data link type */
545 #ifdef HAVE_PCAP_DATALINK_NAME_TO_VAL
546 capture_opts->linktype = linktype_name_to_val(optarg);
547 if (capture_opts->linktype == -1) {
548 cmdarg_err("The specified data link type \"%s\" isn't valid",
552 #else /* HAVE_PCAP_DATALINK_NAME_TO_VAL */
553 /* we can't get the type name, just treat it as a number */
554 capture_opts->linktype = get_natural_int(optarg, "data link type");
555 #endif /* HAVE_PCAP_DATALINK_NAME_TO_VAL */
558 /* the caller is responsible to send us only the right opt's */
559 g_assert_not_reached();
566 * If you change the output format of this function, you MUST update
567 * capture_sync.c:sync_linktype_list_open() accordingly!
570 capture_opts_list_link_layer_types(capture_options *capture_opts, gboolean machine_readable)
572 gchar *err_str, *desc_str;
573 GList *lt_list, *lt_entry;
574 data_link_info_t *data_link_info;
576 /* Get the list of link-layer types for the capture device. */
577 lt_list = get_pcap_linktype_list(capture_opts->iface, &err_str);
578 if (lt_list == NULL) {
579 if (err_str != NULL) {
580 cmdarg_err("The list of data link types for the capture device \"%s\" could not be obtained (%s)."
581 "Please check to make sure you have sufficient permissions, and that\n"
582 "you have the proper interface or pipe specified.\n", capture_opts->iface, err_str);
585 cmdarg_err("The capture device \"%s\" has no data link types.", capture_opts->iface);
588 if (machine_readable) { /* tab-separated values to stdout */
589 for (lt_entry = lt_list; lt_entry != NULL; lt_entry = g_list_next(lt_entry)) {
590 data_link_info = lt_entry->data;
591 if (data_link_info->description != NULL)
592 desc_str = data_link_info->description;
594 desc_str = "(not supported)";
595 printf("%d\t%s\t%s\n", data_link_info->dlt, data_link_info->name,
599 cmdarg_err_cont("Data link types (use option -y to set):");
600 for (lt_entry = lt_list; lt_entry != NULL;
601 lt_entry = g_list_next(lt_entry)) {
602 data_link_info = lt_entry->data;
603 cmdarg_err_cont(" %s", data_link_info->name);
604 if (data_link_info->description != NULL)
605 cmdarg_err_cont(" (%s)", data_link_info->description);
607 cmdarg_err_cont(" (not supported)");
611 free_pcap_linktype_list(lt_list);
616 /* Return an ASCII-formatted list of interfaces. */
617 #define ADDRSTRLEN 46 /* Covers IPv4 & IPv6 */
619 capture_opts_list_interfaces(gboolean machine_readable)
629 char addr_str[ADDRSTRLEN];
631 if_list = get_interface_list(&err, &err_str);
632 if (if_list == NULL) {
634 case CANT_GET_INTERFACE_LIST:
635 cmdarg_err("%s", err_str);
639 case NO_INTERFACES_FOUND:
640 cmdarg_err("There are no interfaces on which a capture can be done");
646 i = 1; /* Interface id number */
647 for (if_entry = g_list_first(if_list); if_entry != NULL;
648 if_entry = g_list_next(if_entry)) {
649 if_info = if_entry->data;
650 printf("%d. %s", i++, if_info->name);
652 if (!machine_readable) {
653 /* Add the description if it exists */
654 if (if_info->description != NULL)
655 printf(" (%s)", if_info->description);
658 * Add the contents of the if_entry struct in a parseable format.
659 * Each if_entry element is tab-separated. Addresses are comma-
662 /* XXX - Make sure our description doesn't contain a tab */
663 if (if_info->description != NULL)
664 printf("\t%s\t", if_info->description);
668 for(ip_addr = g_slist_nth(if_info->ip_addr, 0); ip_addr != NULL;
669 ip_addr = g_slist_next(ip_addr)) {
670 if (ip_addr != g_slist_nth(if_info->ip_addr, 0))
673 if_addr = ip_addr->data;
674 switch(if_addr->type) {
676 if (inet_ntop(AF_INET, &if_addr->ip_addr.ip4_addr, addr_str,
680 printf("<unknown IPv4>");
684 if (inet_ntop(AF_INET6, &if_addr->ip_addr.ip6_addr,
685 addr_str, ADDRSTRLEN)) {
688 printf("<unknown IPv6>");
692 printf("<type unknown %u>", if_addr->type);
696 if (if_info->loopback)
697 printf("\tloopback");
704 free_interface_list(if_list);
709 /* Print the number of packets captured for each interface until we're killed. */
711 capture_opts_print_statistics(gboolean machine_readable)
713 GList *if_list, *if_entry, *stat_list = NULL, *stat_entry;
719 char errbuf[PCAP_ERRBUF_SIZE];
722 if_list = get_interface_list(&err, &err_str);
723 if (if_list == NULL) {
725 case CANT_GET_INTERFACE_LIST:
726 cmdarg_err("%s", err_str);
730 case NO_INTERFACES_FOUND:
731 cmdarg_err("There are no interfaces on which a capture can be done");
737 for (if_entry = g_list_first(if_list); if_entry != NULL; if_entry = g_list_next(if_entry)) {
738 if_info = if_entry->data;
739 pch = pcap_open_live(if_info->name, MIN_PACKET_SIZE, 0, 0, errbuf);
742 if_stat = g_malloc(sizeof(if_stat_t));
743 if_stat->name = g_strdup(if_info->name);
745 stat_list = g_list_append(stat_list, if_stat);
750 cmdarg_err("There are no interfaces on which a capture can be done");
754 if (!machine_readable) {
755 printf("%-15s %10s %10s\n", "Interface", "Received",
759 while (1) { /* XXX - Add signal handling? */
760 for (stat_entry = g_list_first(stat_list); stat_entry != NULL; stat_entry = g_list_next(stat_entry)) {
761 if_stat = stat_entry->data;
762 pcap_stats(if_stat->pch, &ps);
764 if (!machine_readable) {
765 printf("%-15s %10d %10d\n", if_stat->name,
766 ps.ps_recv, ps.ps_drop);
768 printf("%s\t%d\t%d\n", if_stat->name,
769 ps.ps_recv, ps.ps_drop);
780 /* XXX - Not reached. Should we look for 'q' in stdin? */
781 for (stat_entry = g_list_first(stat_list); stat_entry != NULL; stat_entry = g_list_next(stat_entry)) {
782 if_stat = stat_entry->data;
783 pcap_close(if_stat->pch);
784 g_free(if_stat->name);
787 g_list_free(stat_list);
788 free_interface_list(if_list);
794 void capture_opts_trim_snaplen(capture_options *capture_opts, int snaplen_min)
796 if (capture_opts->snaplen < 1)
797 capture_opts->snaplen = WTAP_MAX_PACKET_SIZE;
798 else if (capture_opts->snaplen < snaplen_min)
799 capture_opts->snaplen = snaplen_min;
803 void capture_opts_trim_ring_num_files(capture_options *capture_opts)
805 /* Check the value range of the ring_num_files parameter */
806 if (capture_opts->ring_num_files > RINGBUFFER_MAX_NUM_FILES)
807 capture_opts->ring_num_files = RINGBUFFER_MAX_NUM_FILES;
808 #if RINGBUFFER_MIN_NUM_FILES > 0
809 else if (capture_opts->ring_num_files < RINGBUFFER_MIN_NUM_FILES)
810 capture_opts->ring_num_files = RINGBUFFER_MIN_NUM_FILES;
815 gboolean capture_opts_trim_iface(capture_options *capture_opts, const char *capture_device)
823 /* Did the user specify an interface to use? */
824 if (capture_opts->iface == NULL) {
825 /* No - is a default specified in the preferences file? */
826 if (capture_device != NULL) {
828 capture_opts->iface = g_strdup(capture_device);
829 /* We don't set iface_descr here because doing so requires
830 * capture_ui_utils.c which requires epan/prefs.c which is
831 * probably a bit too much dependency for here...
834 /* No - pick the first one from the list of interfaces. */
835 if_list = get_interface_list(&err, &err_str);
836 if (if_list == NULL) {
839 case CANT_GET_INTERFACE_LIST:
840 cmdarg_err("%s", err_str);
844 case NO_INTERFACES_FOUND:
845 cmdarg_err("There are no interfaces on which a capture can be done");
850 if_info = if_list->data; /* first interface */
851 capture_opts->iface = g_strdup(if_info->name);
852 /* We don't set iface_descr here because doing so requires
853 * capture_ui_utils.c which requires epan/prefs.c which is
854 * probably a bit too much dependency for here...
856 free_interface_list(if_list);
866 #define S_IFIFO _S_IFIFO
869 #define S_ISFIFO(mode) (((mode) & S_IFMT) == S_IFIFO)
872 /* copied from filesystem.c */
873 static int capture_opts_test_for_fifo(const char *path)
877 if (eth_stat(path, &statb) < 0)
880 if (S_ISFIFO(statb.st_mode))
886 static gboolean capture_opts_output_to_pipe(const char *save_file, gboolean *is_pipe)
892 if (save_file != NULL) {
893 /* We're writing to a capture file. */
894 if (strcmp(save_file, "-") == 0) {
895 /* Writing to stdout. */
896 /* XXX - should we check whether it's a pipe? It's arguably
897 silly to do "-w - >output_file" rather than "-w output_file",
898 but by not checking we might be violating the Principle Of
899 Least Astonishment. */
902 /* not writing to stdout, test for a FIFO (aka named pipe) */
903 err = capture_opts_test_for_fifo(save_file);
906 case ENOENT: /* it doesn't exist, so we'll be creating it,
907 and it won't be a FIFO */
908 case 0: /* found it, but it's not a FIFO */
911 case ESPIPE: /* it is a FIFO */
915 default: /* couldn't stat it */
916 cmdarg_err("Error testing whether capture file is a pipe: %s",
926 #endif /* HAVE_LIBPCAP */