Mohawk archive format

General layout

Mohawk archives are organized in chunks, and this is the chunk layout:

• IFF chunk
  • IFF header
  • RSRC header
  • Resource dir
    • Type table
    • Name tables (one for each resource type)
    • Resource tables (one for each resource type)
    • Resource name list
    • File table
  • Actual data (resource contents)

Note that the chunks may be found in a different order: never trust on them being at fixed locations, and use the offsets to reach them.

Every integer is in big-endian (Motorola) byte order.

IFF header

This is always at the beginning of the file.

4 bytes	chunk signature (MHWK), identifies Mohawk archive format
unsigned long	file size in bytes, not counting this IFF header (that is, file size - 8)

RSRC header

I think this is actually the "Resource Dir header". Note that the Dir can be anywhere in file, but this header always follows the IFF Header.

4 bytes	chunk signature (RSRC)
unsigned short	version (always 0x100)
unsigned short	compaction (not used in reading from archives)
unsigned long	total file size in bytes
unsigned long	absolute offset of the Resource Dir
unsigned short	offset in Resource Dir of the File Table
unsigned short	File Table size in bytes

Type table

It lists resource types in the Mohawk file. This table is always at the beginning of the Resource Dir.

Header:

unsigned short	offset in Resource Dir of the Resource Name List (maybe this should go with the RSRC Header)
unsigned short	number of resource types in this file

Entry (one for each type):

4 bytes	resource type (tWAV, tBMP, NAME etc.)
unsigned short	offset in Resource Dir of the Resource Table for this type
unsigned short	offset in Resource Dir of the Name Table for this type

Name table

There is one name table for each resource type. Many types don't have resource names; usually only tBMP, tWAV and tMOV do. Each entry holds the name offset in the name list for a resource.

Header:

unsigned short

number of name entries (can be zero)

Entry:

unsigned short	offset of the name string in Name List
unsigned short	resource index (equal to the resource's index in File Table)

Resource table

Again, there is one resource table for each resource type. The resource table holds crucial information about each resource of this type.

Header:

unsigned short

number of resources for this type (number of table entries)

Entry:

unsigned short	resource ID
unsigned short	index in file table (starting from 1). Also used to find the matching name table entry

Resource name list

This is a simple list of null-terminated strings (C strings), where each string is a resource name. Given a resource, you can get the offset to its name by looking in the name table entry for that resource.

File table

This table holds other important data about each resource, notably the location and size of the resource content within the whole Mohawk file. I wonder why this information couldn't go directly inside the resource table entry.

Header:

unsigned long

number of file table entries

Entry:

unsigned long	absolute offset of resource data block
unsigned short	resource data size, bits 15-0
byte	resource data size, bits 23-16
byte	resource flags (unknown)
unsigned short	unknown (usually zero in Riven files)

It should be noted that the resource data size information is incorrect for all tMOVs in the Riven archives. One can compensate for this by computing file lengths using the resource offsets.