Dumpcap: Fix writing SHBs and IDBs.

If we have a single capture source and that capture source is pcapng and
we're writing a pcapng file, do the following:

- Pass its SHB and IDBs through unmodified. Don't save or write command
  line interface IDBs.

- Save the most recent SHB and IDBs so that we can write them when we're
  writing multiple output files.

If we have multiple capture sources, do the following:

- Write Dumpcap's SHB.

- Keep a global list of IDBs, consisting of both command line interfaces
  and IDBs read from pcapng sources.

- When reading an EPB or ISB, remap its local interface number to its
  corresponding global number.

Add Dumpcap pcapng section tests. Make the application IDs in the
"many_interfaces" captures unique.

Change-Id: I2005934c1f83d839727421960005f106d6c682dd
Reviewed-on: https://code.wireshark.org/review/30085
Petri-Dish: Gerald Combs <gerald@wireshark.org>
Tested-by: Petri Dish Buildbot
Reviewed-by: Gerald Combs <gerald@wireshark.org>

1 files changed, 13 insertions, 1 deletions

diff --git a/test/subprocesstest.py b/test/subprocesstest.py
index 9f6b2f001f..2510ce8992 100644
--- a/test/subprocesstest.py
+++ b/test/subprocesstest.py
@@ -9,7 +9,6 @@
 #
 '''Subprocess test case superclass'''
 
-import config
 import difflib
 import io
 import os
@@ -35,6 +34,19 @@ def cat_dhcp_command(mode):
     sd_cmd += os.path.join(this_dir, 'util_dump_dhcp_pcap.py ' + mode)
     return sd_cmd
 
+def cat_cap_file_command(cap_files):
+    '''Create a command string for dumping one or more capture files to stdout'''
+    # XXX Do this in Python in a thread?
+    if isinstance(cap_files, str):
+        cap_files = [ cap_files ]
+    quoted_paths = ' '.join('"{}"'.format(cap_file) for cap_file in cap_files)
+    if sys.platform.startswith('win32'):
+        # https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-xp/bb491026(v=technet.10)
+        # says that the `type` command "displays the contents of a text
+        # file." Copy to the console instead.
+        return 'copy {} CON'.format(quoted_paths)
+    return 'cat {}'.format(quoted_paths)
+
 class LoggingPopen(subprocess.Popen):
     '''Run a process using subprocess.Popen. Capture and log its output.