Wireshark-dev: Re: [Wireshark-dev] removed functions fast way to find substitutes?

From: Bill Meier <wmeier@xxxxxxxxxxx>
Date: Fri, 21 Nov 2014 09:42:02 -0500
On 11/21/2014 9:29 AM, Pascal Quantin wrote:


2014-11-21 14:06 GMT+01:00 Semjon <semgo@xxxxxx <mailto:semgo@xxxxxx>>:




    Am 21.11.2014 um 10:06 schrieb Guy Harris:
     >
     > On Nov 21, 2014, at 12:48 AM, Semjon
    <semgo-S0/GAf8tV78@xxxxxxxxxxxxxxxx
    <mailto:GAf8tV78@xxxxxxxxxxxxxxxx>> wrote:
     >
     >> One of my current problems is with
     >>
     >> tvb_get_faked_unicode(...)
     >>
     >> which isn't available anymore.
     >> In my Protocol I have some Ascii-encoded String but which comes
    as two
     >> bytes per character. Example:
     >> {0x0031, 0x0032, 0x0033, 0x0034, 0x0000} in tvb should display in
     >> GUI/Tree/PacketList as "1234"
     >
     > If that's truly ASCII-encoded, that would be a significant waste
    of bytes - you could just use one byte per character for ASCII; if
    the second byte is always zero, that byte serves no useful purpose.
     >
     > So I'll assume it's a *superset* of ASCII, and that you mean
    either "UTF-16 encoded string" or "UCS-2 encoded string" rather than
    "ASCII-encoded string which comes as two bytes per character".
     >
     > So:
     >
     >> I used to call:
     >>
     >> tvb_get_faked_unicode(NULL,tvb, 20,
    ((tvb_length(tvb)-20)/2),ENC_BIG_ENDIAN)
     >>
     >> and display result as %s in col_append_fstr() or as FT_STRING in
     >> proto_tree_add_string().
     >>
     >> So could anyone give me a hint, is there a function still
    available for
     >> this type of encoding
     >
     >       tvb_get_string_enc(tvb, {offset}, {length of string},
    ENC_UTF_16|ENC_BIG_ENDIAN)
     >
     > or
     >
     >       tvb_get_string_enc(tvb, {offset}, {length of string},
    ENC_UCS_2|ENC_BIG_ENDIAN)
     >
     > depending on whether it's UTF-16 (with surrogate pairs to handle
    Unicode characters that don't fit in 16 bits) or UCS-2 (supporting
    only characters in the Unicode Basic Multilingual Plane, without
    surrogate pairs).
     >
     > Note that tvb_get_string_enc() returns a UTF-8-encoded string;
    octet sequences that can't be mapped to UTF-8 strings will be
    replaced by the Unicode "replacement character".
     >
     >> In general is there a fast/convenient way - other than manually
    looking
     >> through the sources after functions that might do what i want -
    to check
     >> if this function X is now replaced by function Y.
     >
     > No.  You could check doc/README.developer, etc. to see if
    anything is mentioned.
     >
     >> Other examples I need to replace are:
     >> abs_time_to_ep_str()
     >
     >       abs_time_to_str({wmem scope}, ...)
     >
     > The old "ephemeral" and "session" memory mechanisms are
    deprecated in favor of the new wmem mechanisms.  The scope that's
    equivalent to "ephemeral" scope is, I think, packet scope (right,
    Evan?), so you'd want
     >
     >       abs_time_to_str(wmem_packet_scope(), ...)
     >
     >> nstime_delta()
     >
     > Its replacement is called nstime_delta() and has the exact same
    arguments. :-)
     >
     > However, you need to include <wsutil/nstime.h> to get it declared.
     >

    Well thanks a lot everybody for helping. I could resolve almost all of
    my Problems with Your help. In fact the "ASCII encoded 2-byte-string" is
    a Unicode String shame on me :-)

    Unfortunately no luck with nstime_delta().

    I already had included  <wsutil/nstime.h>

    My call looks like this:

             proto_item *it;
             nstime_t ns;

             it=proto_tree_add_uint(xyz_tree, hf_xyz_response_to, tvb, 0, 0,
    xyz_trans->req_frame);
             PROTO_ITEM_SET_GENERATED(it);

             nstime_delta(&ns, &pinfo->fd->abs_ts, &xyz_trans->req_time);
             it=proto_tree_add_time(xyz_tree, hf_xyz_response_time, tvb, 0,
    0, &ns);
             PROTO_ITEM_SET_GENERATED(it);

    It always generates errors LNK2019/LNK1120 ... unresolved external
    symbol "__imp__nstime_delta" in function ...

    Hope You have an idea here. I'm not really good in finding the necessary
    functions/files to include in such a big project and my search on the
    www on this was not successful.


Hi,

assuming that your proprietary dissector is a plugin, ensure that your
makefile indicates the path to libwsutil. I guess you are on Windows, so
your Makefile.nmake file should contain:

!IFDEF ENABLE_LIBWIRESHARK
LINK_PLUGIN_WITH= ..\..\wsutil\libwsutil.lib
CFLAGS=$(CFLAGS)




See plugins\ethercat for a dissector which uses nstime_delta() [in packet-esl.c].

Also: proto.h (#included by packet.h) #includes nstime.h so you need not explicitly include same.