Garry's Mod Addon

Revision as of 22:32, 14 July 2016

Garry's Mod Addon files are used in the PC game Garry's Mod for storing downloadable game content. They store game files in a hierarchy of folders, so gma files can be create from a folder, or extracted into a hierarchy of folders.

Format

char[4] ident

uint8 version

uint64 steam_id (unused)

uint64 timestamp

uint8 zero (0)

char addon_name (null terminated string of variable size)

char addon_description (null terminated string of variable size)

char addon_author (null terminated string of variable size) ("Author Name")

uint32 addon_version

struct file_table

uint32 file_number

char file_path (null terminated string of variable size)

uint64 file_size

uint32 file_crc

uint32 zero (0)

struct files

byte file (file data based on information from the file table)

uint32 addon_crc

Links

• How to create and extract gma files
• Source code for gmad to create and extract gma files