Difference between revisions of "Bitbake Cheat Sheet"

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Here are some quick notes on bitbake syntax and rules.  For an exhaustive list of functionality, and
 
Here are some quick notes on bitbake syntax and rules.  For an exhaustive list of functionality, and
longer descriptions, see the bitbake manual at: http://docs.openembedded.org/bitbake/html/ (note that this
+
longer descriptions, see the bitbake manual at: http://docs.openembedded.org/bitbake/html/
link goes to the OpenEmbedded version of the bitbake manual, which is a version from 2006 as of this writing.  A separate (yocto-specific?) bitbake manual is included in source form in the yocto project source directory, under bitbake/doc.)
+
 
== Options ==
+
Note that this link goes to the OpenEmbedded version of the bitbake manual, which is a version from 2006 as of this writing.  A separate bitbake manual is included in source form in the yocto project source directory, under bitbake/doc. The yocto version of the manual is more recent, but I can't find a published version of it to link to.
 +
 
 +
== Command Line options ==
 +
Here are a few commonly-used command line options.
 
{| border="1" cellspacing="0" cellpadding="5"
 
{| border="1" cellspacing="0" cellpadding="5"
 
|-bgcolor="#80c0d0"
 
|-bgcolor="#80c0d0"
Line 28: Line 31:
 
|}
 
|}
  
== Syntax ==
+
== User interfaces ==
 +
Bitbake can be used with several different user interfaces.  Here are some options:
 +
{| border="1" cellspacing="0" cellpadding="5"
 +
|-bgcolor="#80c0d0"
 +
! style="width: 200px;" | User interface
 +
! Type
 +
! NOTES
 +
|-
 +
|bitbake <recipe-or-image> ''or''<br> "bitbake -u knotty <recipe-or-image>"
 +
|scrolling text interface
 +
|This is the default user interface
 +
|-
 +
|bitbake -u ncurses <recipe-or-image>
 +
|text-window based interface
 +
|I couldn't figure out how to control or exit this interface
 +
|-
 +
|bitbake -u hob
 +
|graphical interface
 +
|This is a full graphical interface which includes selecting machine, distro, etc. and performing a build
 +
|-
 +
|bitbake -u goggle <recipe-or-image>
 +
|simple graphical interface
 +
|This is a simple graphical wrapper over the streaming text output of bitbake.  It's nice in that it shows collapsible trees for the logs for sub-tasks for each recipe.
 +
|}
  
 +
== .bb file syntax ==
 +
This table lists some of the syntax found in recipe (.bb) files.
 
{| border="1" cellspacing="0" cellpadding="5"
 
{| border="1" cellspacing="0" cellpadding="5"
 
|-bgcolor="#80c0d0"
 
|-bgcolor="#80c0d0"
! style="width: 250px;" | Syntax
+
! style="width: 270px;" | Syntax
 
! Meaning
 
! Meaning
 
! NOTES
 
! NOTES
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|-
 
|-
 
|VAR =. "foo"||prepend without space||
 
|VAR =. "foo"||prepend without space||
 +
|-
 +
|VAR_append = "foo" ||append without space||
 
|-
 
|-
 
|OVERRIDES="string1:string2"<BR>
 
|OVERRIDES="string1:string2"<BR>
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|OVERRIDES="string1:string2"<BR>
 
|OVERRIDES="string1:string2"<BR>
 
VAR = "foo"<BR>
 
VAR = "foo"<BR>
VAR_appends_string1 = " bar"
+
VAR_append_string1 = " bar"
|conditional appending
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|conditional append
|if string1 in in OVERRIDES, then append " bar" to the value of VAR
+
|if string1 is in OVERRIDES, then append " bar" to the value of VAR
 +
|-
 +
|BBVERSIONS="1.0 1.8 string"<BR>
 +
VAR="foo"<BR>
 +
VAR_string="bar"
 +
|range-specific conditional
 +
|If the version of the package is in the specified range (1.0-1.8 in this example), then perform an override on the indicated variable
 +
|-
 +
|VAR = "foo ${@<line-of-python-code>}"
 +
|python code expansion
 +
|ex: VAR = "the date is: ${@time.strftime(’%Y%m%d’,time.gmtime())}"
 +
|-
 +
|include foo||include file||include file named "foo", search BBPATH
 +
|-
 +
|require [<path>]foo||require file||include file named "foo", failing if not found exactly where specified
 +
|-
 +
|inherit foo||inherit classes||include definitions from foo.bbclass
 +
|-
 +
|do_sometask() {<BR>
 +
    <shell code><BR>
 +
}
 +
|define a task using shell code
 +
|
 +
|-
 +
|python do_sometask {<BR>
 +
    <python code><BR>
 +
}
 +
|define a task using python code
 +
|
 +
|-
 +
|addtask sometask (before<nowiki>|</nowiki>after) other_task
 +
|add a task
 +
|adds a defined task to the list of tasks, with the ordering specified.  Zero or more 'before' or 'after' clauses can be used.
 +
|-
 +
|VAR[some_flag]="foo"
 +
|associate a subsidiary flag value to a variable
 +
|a few subsidiary flag value names are well-defined: "dirs", "cleandirs", "noexec", "nostamp", "fakeroot", "umask", "deptask", "rdeptask", "recdeptask", "recrdeptask"
 +
Flag values appear to be used exclusively with task definitions (i.e. do_sometask)
 +
|}
 +
 
 +
== Additional bitbake-related commands ==
 +
{| border="1" cellspacing="0" cellpadding="5"
 +
|-bgcolor="#80c0d0"
 +
! Command
 +
! Description
 +
! NOTES
 +
|-
 +
|bitbake-layers
 +
|Show information about layers and recipes
 +
|Included in the bitbake/bin directory in yocto.
 +
|-
 +
|bitbake-env
 +
|Show invidividual bitbake variable values
 +
|see: http://www.crashcourse.ca/wiki/index.php/OE_bitbake-env_utility
 +
|-
 +
|bitbake -g -u depexp <recipe-or-image-name>
 +
|Show dependency information in a graphical interface
 +
|
 
|}
 
|}

Latest revision as of 00:17, 21 December 2012

Here are some quick notes on bitbake syntax and rules. For an exhaustive list of functionality, and longer descriptions, see the bitbake manual at: http://docs.openembedded.org/bitbake/html/

Note that this link goes to the OpenEmbedded version of the bitbake manual, which is a version from 2006 as of this writing. A separate bitbake manual is included in source form in the yocto project source directory, under bitbake/doc. The yocto version of the manual is more recent, but I can't find a published version of it to link to.

Command Line options

Here are a few commonly-used command line options.

Option Meaning
-c <task> execute <task> for the image or recipe being built. ex: bitbake -c fetch busybox.

Some of the possible tasks are: fetch, configure, compile, package, clean

-f force execution of the operation, even if not required
-v show verbose output
-DDD show lots of debug information
-s show recipe version information
--help get usage help
-c listtasks <image-or-recipe-name> show the tasks associated with an image or individual recipe
-g <recipe> output dependency tree in graphviz format

User interfaces

Bitbake can be used with several different user interfaces. Here are some options:

User interface Type NOTES
bitbake <recipe-or-image> or
"bitbake -u knotty <recipe-or-image>"
scrolling text interface This is the default user interface
bitbake -u ncurses <recipe-or-image> text-window based interface I couldn't figure out how to control or exit this interface
bitbake -u hob graphical interface This is a full graphical interface which includes selecting machine, distro, etc. and performing a build
bitbake -u goggle <recipe-or-image> simple graphical interface This is a simple graphical wrapper over the streaming text output of bitbake. It's nice in that it shows collapsible trees for the logs for sub-tasks for each recipe.

.bb file syntax

This table lists some of the syntax found in recipe (.bb) files.

Syntax Meaning NOTES
VAR = "foo" simple assignment
VAR ?= "foo" assign if no other value is already assigned (default assignment)
VAR ??=foo weak default assignment takes lower precedence than ?=
VAR = "stuff ${OTHER_VAR} more" variable expansion OTHER_VAR expanded at time of reference to VAR
VAR := "stuff ${OTHER_VAR} more" immediate variable expansion OTHER_VAR expanded at time of parsing this line
VAR += "foo" append with space
VAR =+ "foo" prepend with space
VAR .= "foo" append without space
VAR =. "foo" prepend without space
VAR_append = "foo" append without space
OVERRIDES="string1:string2"

VAR = "foo"
VAR_string1 = "bar"

alternate/override value if string1 is listed in OVERRIDES, use "bar" for value of VAR, otherwise use "foo"
OVERRIDES="string1:string2"

VAR = "foo"
VAR_append_string1 = " bar"

conditional append if string1 is in OVERRIDES, then append " bar" to the value of VAR
BBVERSIONS="1.0 1.8 string"

VAR="foo"
VAR_string="bar"

range-specific conditional If the version of the package is in the specified range (1.0-1.8 in this example), then perform an override on the indicated variable
VAR = "foo ${@<line-of-python-code>}" python code expansion ex: VAR = "the date is: ${@time.strftime(’%Y%m%d’,time.gmtime())}"
include foo include file include file named "foo", search BBPATH
require [<path>]foo require file include file named "foo", failing if not found exactly where specified
inherit foo inherit classes include definitions from foo.bbclass
do_sometask() {
   <shell code>

}

define a task using shell code
python do_sometask {
   <python code>

}

define a task using python code
addtask sometask (before|after) other_task add a task adds a defined task to the list of tasks, with the ordering specified. Zero or more 'before' or 'after' clauses can be used.
VAR[some_flag]="foo" associate a subsidiary flag value to a variable a few subsidiary flag value names are well-defined: "dirs", "cleandirs", "noexec", "nostamp", "fakeroot", "umask", "deptask", "rdeptask", "recdeptask", "recrdeptask"

Flag values appear to be used exclusively with task definitions (i.e. do_sometask)

Additional bitbake-related commands

Command Description NOTES
bitbake-layers Show information about layers and recipes Included in the bitbake/bin directory in yocto.
bitbake-env Show invidividual bitbake variable values see: http://www.crashcourse.ca/wiki/index.php/OE_bitbake-env_utility
bitbake -g -u depexp <recipe-or-image-name> Show dependency information in a graphical interface