Thanks Pascal,
d > On 20 Jul 2016, at 19:21, Pascal Quantin <pascal.quan...@gmail.com> wrote: > > Hi David, > > 2016-07-20 9:56 GMT+02:00 David Arnold <dav...@pobox.com > <mailto:dav...@pobox.com>>: > I’m writing a dissector for a protocol that includes a 96 bit (12 byte) > big-endian integer value. > > I’d like to display it as a decimal number. I’m happy to write a BASE_CUSTOM > renderer for it, but how should it be described in the hf_register_info array? > > In my dissect() function, I have > > proto_tree_add_item(ouch_asx_tree, > hf_ouch_asx_match_id, > tvb, offset, 12, > ENC_BIG_ENDIAN); > offset += 12; > > In the hf_register_info array, I’d have something like > > { &hf_ouch_asx_match_id, > { "Match ID", "ouch_asx.match_id", > FT_BYTES, BASE_CUSTOM, CF_FUNC(format_match_id), 0x0, NULL, HFILL > }}, > > except that generates a runtime error: > > Err Field 'Match ID' (ouch-asx.match_id) has a 'strings' value but > is of type FT_BYTES (which is not allowed to have strings) > > Quick hint, someone? > > You cannot use BASE_CUSTOM for this use case, as explained in > doc/README.dissector: > > "BASE_CUSTOM allows one to specify a callback function pointer that will > format the value. > > For 32-bit and smaller values, custom_fmt_func_t can be used to declare > the callback function pointer. Specifically, this is defined as: > > void func(gchar *, guint32); > > For values larger than 32-bits, custom_fmt_func_64_t can be used to declare > the callback function pointer. Specifically, this is defined as: > > void func(gchar *, guint64); > > The first argument is a pointer to a buffer of the ITEM_LABEL_LENGTH size > and the second argument is the value to be formatted. > > Both custom_fmt_func_t and custom_fmt_func_64_t are defined in epan/proto.h." > > So it can only work with FT_(U_)INTX types. > > Instead you probably want to use proto_tree_add_bytes_format_value() taht > gives you a full control on what is displayed in the tree. > > > Regards, > Pascal. > > ___________________________________________________________________________ > Sent via: Wireshark-dev mailing list <wireshark-dev@wireshark.org > <mailto:wireshark-dev@wireshark.org>> > Archives: https://www.wireshark.org/lists/wireshark-dev > <https://www.wireshark.org/lists/wireshark-dev> > Unsubscribe: https://wireshark.org/mailman/options/wireshark-dev > <https://wireshark.org/mailman/options/wireshark-dev> > mailto:wireshark-dev-requ...@wireshark.org?subject=unsubscribe > <mailto:wireshark-dev-requ...@wireshark.org?subject=unsubscribe>
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