Clean up handling of --capture-comment.

Don't store the comments in a capture_options structure, because that's
available only if we're being built with capture support, and
--capture-comment can be used in TShark when reading a capture file and
writing another capture file, with no live capture taking place.

This means we don't handle that option in capture_opts_add_opt(); handle
it in the programs that support it.

Support writing multiple comments in dumpcap when capturing.

These changes also fix builds without pcap, and makes --capture-comment
work in Wireshark when a capture is started from the command line with
-k.

Update the help messages to indicate that --capture-comment adds a
capture comment, it doesn't change any comment (much less "the" comment,
as there isn't necessarily a single comment).

Update the man pages:

- not to presume that only pcapng files support file comments (even if
that's true now, it might not be true in the future);
- to note that multiple instances of --capture-comment are supported,
and that multiple comments will be written, whether capturing or reading
one file and writing another;
- clarify that Wireshark doesn't *discard* SHB comments other than the
first one, even though it only displays the first one;

1 files changed, 13 insertions, 5 deletions

diff --git a/dumpcap.c b/dumpcap.c
index e54725520a..e8e8323429 100644
--- a/dumpcap.c
+++ b/dumpcap.c
@@ -336,6 +336,7 @@ dumpcap_log_writer(const char *domain, enum ws_log_level level,
 
 /* capture related options */
 static capture_options global_capture_opts;
+static GPtrArray *capture_comments = NULL;
 static gboolean quiet = FALSE;
 static gboolean use_threads = FALSE;
 static guint64 start_time;
@@ -3099,7 +3100,7 @@ capture_loop_init_pcapng_output(capture_options *capture_opts, loop_data *ld,
         get_cpu_info(cpu_info_str);
 
         successful = pcapng_write_section_header_block(ld->pdh,
-                                                       (const char *)capture_opts->capture_comment,   /* Comment */
+                                                       capture_comments,   /* Comments */
                                                        cpu_info_str->str,           /* HW */
                                                        os_info_str->str,            /* OS */
                                                        get_appname_and_version(),
@@ -4815,6 +4816,7 @@ get_dumpcap_runtime_info(GString *str)
 
 #define LONGOPT_IFNAME             LONGOPT_BASE_APPLICATION+1
 #define LONGOPT_IFDESCR            LONGOPT_BASE_APPLICATION+2
+#define LONGOPT_CAPTURE_COMMENT    LONGOPT_BASE_APPLICATION+3
 
 /* And now our feature presentation... [ fade to music ] */
 int
@@ -4828,6 +4830,7 @@ main(int argc, char *argv[])
         LONGOPT_CAPTURE_COMMON
         {"ifname", required_argument, NULL, LONGOPT_IFNAME},
         {"ifdescr", required_argument, NULL, LONGOPT_IFDESCR},
+        {"capture-comment", required_argument, NULL, LONGOPT_CAPTURE_COMMENT},
         {0, 0, 0, 0 }
     };
 
@@ -5139,7 +5142,6 @@ main(int argc, char *argv[])
         case 's':        /* Set the snapshot (capture) length */
         case 'w':        /* Write to capture file x */
         case 'y':        /* Set the pcap data link type */
-        case LONGOPT_CAPTURE_COMMENT: /* add a capture comment */
 #ifdef HAVE_PCAP_REMOTE
         case 'u':        /* Use UDP for data transfer */
         case 'r':        /* Capture own RPCAP traffic too */
@@ -5183,6 +5185,12 @@ main(int argc, char *argv[])
                 exit_main(1);
             }
             break;
+        case LONGOPT_CAPTURE_COMMENT:  /* capture comment */
+            if (capture_comments == NULL) {
+                capture_comments = g_ptr_array_new_with_free_func(g_free);
+            }
+            g_ptr_array_add(capture_comments, g_strdup(optarg));
+            break;
         case 'Z':
             capture_child = TRUE;
 #ifdef _WIN32
@@ -5319,10 +5327,10 @@ main(int argc, char *argv[])
             global_capture_opts.use_pcapng = TRUE;
         }
 
-        if (global_capture_opts.capture_comment &&
+        if (capture_comments &&
             (!global_capture_opts.use_pcapng || global_capture_opts.multi_files_on)) {
-            /* XXX - for ringbuffer, should we apply the comment to each file? */
-            cmdarg_err("A capture comment can only be set if we capture into a single pcapng file.");
+            /* XXX - for ringbuffer, should we apply the comments to each file? */
+            cmdarg_err("Capture comments can only be set if we capture into a single pcapng file.");
             exit_main(1);
         }