LAR Design - Revision history

Hailfinger at 21:13, 7 November 2009

2009-11-07T21:13:36Z

Stuge: Add box with info about CBFS being used in trunk

2009-11-07T20:26:52Z

Add box with info about CBFS being used in trunk

Stepan: /* Introduction */

2008-01-15T15:15:15Z

‎Introduction

Stepan at 15:12, 15 January 2008

2008-01-15T15:12:35Z

PatrickGeorgi: /* Archive format */

2007-06-22T12:21:26Z

‎Archive format

PatrickGeorgi: /* Discussion */

2007-06-22T12:17:35Z

‎Discussion

Stepan: /* TODO */

2007-06-22T12:07:28Z

‎TODO

Stepan: New page: = Introduction = LAR is the LinuxBIOS Archiver. It is a small utility that we use to create and change LinuxBIOS images and their modules. It is a simple archiver, similar to cpio, ar or...

2007-06-22T12:01:49Z

New page: = Introduction = LAR is the LinuxBIOS Archiver. It is a small utility that we use to create and change LinuxBIOS images and their modules. It is a simple archiver, similar to cpio, ar or...

New page

= Introduction =

LAR is the LinuxBIOS Archiver. It is a small utility that we use to create and change LinuxBIOS images and their modules.

It is a simple archiver, similar to cpio, ar or tar.

Design goals were
- minimum overhead
- maximum fault tolerance
- simplicity

For a usage example see example.c.

For questions contact Stefan Reinauer <stepan@coresystems.de>.

= Usage =

Create archive archive.lar containing files file1 ... fileN:

$ lar c archive.lar file1 ... fileN

Extract files from archive.lar:

$ lar x archive.lar [file1 ... fileN]

List files in archive:

$ lar l archive.lar

= Archive format =

The rough format is:

|--------------|
| header |
|--------------|
| data |
|--------------|
| header |
|--------------|
| data |
|--------------|
...

Headers have to be 16 byte aligned.

Headers have to be 16 byte aligned.

|----------------------------|
| magic (8 bytes) |
|----------------------------|
| length (4 bytes) |
|----------------------------|
| checksum (4 bytes) |
|----------------------------|
| offset to blob (4 bytes) |
|----------------------------|
| "path name" | <-- null terminated, aligned to 16 bytes
|----------------------------|
| blob (aligned to 16 bytes) |
|----------------------------|

= TODO =

* Reading flash layouts
* This does not enforce any alignment yet
* Alignment enforcing will be optional

@@ Line 1: / Line 1: @@
 <div style="margin:0.5em 0; padding:0.5em; background:#ffd0d0; border:1px solid #aabbcc;">
-Please note that LAR has been replaced with [[CBFS]] in coreboot trunk, but LAR is still used for coreboot v3.
+Please note that LAR is not used in coreboot v2 trunk (which has the alternative [[CBFS]]), but LAR is still used for coreboot v3.
 </div>
 = Introduction =
 LAR is the coreboot archiver. It is a small utility that we use to create and change coreboot images and their modules.

← Older revision		Revision as of 20:26, 7 November 2009
Line 1:		Line 1:
		+	<div style="margin:0.5em 0; padding:0.5em; background:#ffd0d0; border:1px solid #aabbcc;">
		+	Please note that LAR has been replaced with [[CBFS]] in coreboot trunk, but LAR is still used for coreboot v3.
		+	</div>
		+
	= Introduction =		= Introduction =

@@ Line 1: / Line 1: @@
 = Introduction =
-LAR is the LinuxBIOS Archiver. It is a small utility that we use to create and change LinuxBIOS images and their modules.
+LAR is the coreboot archiver. It is a small utility that we use to create and change coreboot images and their modules.
 It is a simple archiver, similar to cpio, ar or tar.
@@ Line 92: / Line 92: @@
 Example:
-* normal/initram=../../build/linuxbios.initram * none
+* normal/initram=../../build/coreboot.initram * none
-means: the file "normal/initram" inside the lar file will be created from "../../build/linuxbios.initram", with "none" compression. size isn't given and taken from the existing file
+means: the file "normal/initram" inside the lar file will be created from "../../build/coreboot.initram", with "none" compression. size isn't given and taken from the existing file
 Some syntax examples
-  $ lar x linuxbios.rom # create linuxbios/* and linuxbios/MANIFEST
+  $ lar x coreboot.rom # create coreboot/* and coreboot/MANIFEST
-  $ lar c linuxbios.rom linuxbios/ # looks for linuxbios/MANIFEST
+  $ lar c coreboot.rom coreboot/ # looks for coreboot/MANIFEST
-  $ lar x linuxbios.rom # image without payload
+  $ lar x coreboot.rom # image without payload
   $ cp payload.bin
-  $ lar c linuxbios.rom linuxbios/ -s 512K
+  $ lar c coreboot.rom coreboot/ -s 512K
   $ # creates image, overiding size to 512K

@@ Line 71: / Line 71: @@
 = Discussion =
-Patrick Mauritz and Stefan Reinauer discussed extending LAR so that it handles a MANIFEST file.
+Patrick Georgi and Stefan Reinauer discussed extending LAR so that it handles a MANIFEST file.
 This file will list all existing files, and their current compression. If a file is in the MANIFEST, it's compression status will not be changed. This feature is required for making sure that initram is not compressed.
@@ Line 77: / Line 77: @@
 MANIFEST will describe
 * compression of files
-* size of the unpacked image
+* size of the unpacked image (optional on parse-time, to make it easier for "lar c" users)
 * bootblock name
 * other metadata?
 Some syntax examples

← Older revision		Revision as of 12:07, 22 June 2007
Line 68:		Line 68:
	* This does not enforce any alignment yet		* This does not enforce any alignment yet
	* Alignment enforcing will be optional		* Alignment enforcing will be optional
		+
		+	= Discussion =
		+
		+	Patrick Mauritz and Stefan Reinauer discussed extending LAR so that it handles a MANIFEST file.
		+
		+	This file will list all existing files, and their current compression. If a file is in the MANIFEST, it's compression status will not be changed. This feature is required for making sure that initram is not compressed.
		+
		+	MANIFEST will describe
		+	* compression of files
		+	* size of the unpacked image
		+	* bootblock name
		+	* other metadata?
		+
		+	Some syntax examples
		+
		+	$ lar x linuxbios.rom # create linuxbios/* and linuxbios/MANIFEST
		+
		+	$ lar c linuxbios.rom linuxbios/ # looks for linuxbios/MANIFEST
		+
		+	$ lar x linuxbios.rom # image without payload
		+	$ cp payload.bin
		+	$ lar c linuxbios.rom linuxbios/ -s 512K
		+	$ # creates image, overiding size to 512K

@@ Line 12: / Line 12: @@
 For a usage example see example.c.
-For questions contact Stefan Reinauer <stepan@coresystems.de>.
+For questions contact [mailto:stepan@coresystems.de Stefan Reinauer].
-−
 = Usage =

@@ Line 46: / Line 46: @@
 Headers have to be 16 byte aligned.
-Headers have to be 16 byte aligned.
+Data blocks have to be 16 byte aligned.
   |----------------------------|
   | magic (8 bytes)            |
   |----------------------------|
-  | length (4 bytes)           |
+  | compressed length (4 bytes)|
   |----------------------------|
   | checksum (4 bytes)         |
   |----------------------------|
   | offset to blob (4 bytes)   |
   |----------------------------|
-  | "path name"                | <-- null terminated, aligned to 16 bytes
+  | compression id (4 bytes)   |
   |----------------------------|
   | blob (aligned to 16 bytes) |
   |----------------------------|
 = TODO =