The controls on this page let you define fields in specific
groups of binary files.
The list contains all the fields for a file type. In
the Binary Comparisons options panel, you will be
able to enable or disable them by role using
checkboxes. The New and Edit buttons open the Field
details dialog box. Use the Remove button to delete a
field from the list.
Each field contains the following information:
a
name: used to be displayed in the list
a
role: used to describe the kind of things
the field contains. The roles from all the declared
fields are gathered in the Binary Comparison options
panel. By checking a single role in the Binary
Comparison options panel, ECMerge will ignore all the fields
with that role in the binary files. For example, use
names such as "Timestamp", "Comment", "Random
filling"...
a
dynamic field flag
if static field, its
start and
length.
Dynamic field are defined in a script you can edit just
below the fields list. The PE File format is provided in
the factory-file-types directory of the installation (as
ms-executable.ecmft), this is a good sample of how to write
such a script to define dynamic fields ranges.
The target of the script is to fill a collection
dynamic_fields from the
content object which represents the content of the
dinary file. Here is a basic example of what is
expected:
var timestamp_field = new BinaryDocument.Field;
timestamp_field.name = "Header Time";
timestamp_field.role = "Timestamp";
// let's imagine the location of
the timestamp field is stored at offset 16
// in the file as a 32 bit offset itself (in a
little endian unsigned int)
timestamp_field.start = content.read_number (16,
4, 'little', 'uint');
timestamp_field.length = 8; // 8 bytes for a 64
bits timestamp
dynamic_fields.push (timestamp_field);
