The first 16 bytes of every Genesis project file are:
ca2f 5ef5 00d8 ef0b 8074 18d0 e40b 7a4f
I got this from /dev/random.
This uniquely identifies the file as a Genesis project file. The default file
extension is .gdaw.
After this contains an ordered list of transactions. A transaction is a set of edits. There are 2 types of edits: put and delete.
A put contains a key and a value, each of which is a variable number of bytes. A delete contains only a key, which is a variable number of bytes.
A transaction looks like this:
| Offset | Description |
|---|---|
| 0 | uint32be length of transaction in bytes including this field |
| 4 | uint32be crc32 of this transaction |
| 8 | uint32be number of put edits in this transaction |
| 12 | uint32be number of delete edits in this transaction |
| 16 | the put edits in this transaction |
| - | the delete edits in this transaction |
A put edit looks like:
| Offset | Description |
|---|---|
| 0 | uint32be key length in bytes |
| 4 | uint32be value length in bytes |
| 8 | key bytes |
| - | value bytes |
A delete edit looks like:
| Offset | Description |
|---|---|
| 0 | uint32be key length in bytes |
| 4 | key bytes |
That's it. To read the file, apply the transactions in order. To update a file, append a transaction. Periodically "garbage collect" by creating a new project file with a single transaction with all the data, and then atomically rename the new project file over the old one.