bitbake: sphinx: initial sphinx support

This commit is autogenerated pandoc to generate an inital set
of reST files based on DocBook XML files.

A .rst file is generated for each .xml files in all manuals with this
command:

cd <manual>
for i in *.xml; do \
  pandoc -f docbook -t rst --shift-heading-level-by=-1 \
  $i -o $(basename $i .xml).rst \
done

The conversion was done with: pandoc 2.9.2.1-91 (Arch Linux).

Also created an initial top level index file for each document, and
added all 'books' to the top leve index.rst file.

The YP manuals layout is organized as:

Book
  Chapter
    Section
      Section
        Section

Sphinx uses section headers to create the document structure.
ReStructuredText defines sections headers like that:

   To break longer text up into sections, you use section headers. These
   are a single line of text (one or more words) with adornment: an
   underline alone, or an underline and an overline together, in dashes
   "-----", equals "======", tildes "~~~~~~" or any of the
   non-alphanumeric characters = - ` : ' " ~ ^ _ * + # < > that you feel
   comfortable with. An underline-only adornment is distinct from an
   overline-and-underline adornment using the same character. The
   underline/overline must be at least as long as the title text. Be
   consistent, since all sections marked with the same adornment style
   are deemed to be at the same level:

Let's define the following convention when converting from Docbook:

Book                => overline ===   (Title)
  Chapter           => overline ***   (1.)
    Section         => ====           (1.1)
      Section       => ----           (1.1.1)
        Section     => ~~~~           (1.1.1.1)
          Section   => ^^^^           (1.1.1.1.1)

During the conversion with pandoc, we used --shift-heading-level=-1 to
convert most of DocBook headings automatically. However with this
setting, the Chapter header was removed, so I added it back
manually. Without this setting all headings were off by one, which was
more difficult to manually fix.

At least with this change, we now have the same TOC with Sphinx and
DocBook.

(Bitbake rev: 6bf6c8d63787aed7624793c24af3fa603b5ac961)

Signed-off-by: Nicolas Dechesne <nicolas.dechesne@linaro.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 629 insertions, 0 deletions

diff --git a/bitbake/doc/bitbake-user-manual/bitbake-user-manual-fetching.rst b/bitbake/doc/bitbake-user-manual/bitbake-user-manual-fetching.rst
new file mode 100644
index 0000000000..4285a73afe
--- /dev/null
+++ b/bitbake/doc/bitbake-user-manual/bitbake-user-manual-fetching.rst
@@ -0,0 +1,629 @@
+=====================
+File Download Support
+=====================
+
+BitBake's fetch module is a standalone piece of library code that deals
+with the intricacies of downloading source code and files from remote
+systems. Fetching source code is one of the cornerstones of building
+software. As such, this module forms an important part of BitBake.
+
+The current fetch module is called "fetch2" and refers to the fact that
+it is the second major version of the API. The original version is
+obsolete and has been removed from the codebase. Thus, in all cases,
+"fetch" refers to "fetch2" in this manual.
+
+The Download (Fetch)
+====================
+
+BitBake takes several steps when fetching source code or files. The
+fetcher codebase deals with two distinct processes in order: obtaining
+the files from somewhere (cached or otherwise) and then unpacking those
+files into a specific location and perhaps in a specific way. Getting
+and unpacking the files is often optionally followed by patching.
+Patching, however, is not covered by this module.
+
+The code to execute the first part of this process, a fetch, looks
+something like the following: src_uri = (d.getVar('SRC_URI') or
+"").split() fetcher = bb.fetch2.Fetch(src_uri, d) fetcher.download()
+This code sets up an instance of the fetch class. The instance uses a
+space-separated list of URLs from the ```SRC_URI`` <#var-bb-SRC_URI>`__
+variable and then calls the ``download`` method to download the files.
+
+The instantiation of the fetch class is usually followed by: rootdir =
+l.getVar('WORKDIR') fetcher.unpack(rootdir) This code unpacks the
+downloaded files to the specified by ``WORKDIR``.
+
+.. note::
+
+   For convenience, the naming in these examples matches the variables
+   used by OpenEmbedded. If you want to see the above code in action,
+   examine the OpenEmbedded class file
+   base.bbclass
+   .
+
+The ``SRC_URI`` and ``WORKDIR`` variables are not hardcoded into the
+fetcher, since those fetcher methods can be (and are) called with
+different variable names. In OpenEmbedded for example, the shared state
+(sstate) code uses the fetch module to fetch the sstate files.
+
+When the ``download()`` method is called, BitBake tries to resolve the
+URLs by looking for source files in a specific search order:
+
+-  *Pre-mirror Sites:* BitBake first uses pre-mirrors to try and find
+   source files. These locations are defined using the
+   ```PREMIRRORS`` <#var-bb-PREMIRRORS>`__ variable.
+
+-  *Source URI:* If pre-mirrors fail, BitBake uses the original URL (e.g
+   from ``SRC_URI``).
+
+-  *Mirror Sites:* If fetch failures occur, BitBake next uses mirror
+   locations as defined by the ```MIRRORS`` <#var-bb-MIRRORS>`__
+   variable.
+
+For each URL passed to the fetcher, the fetcher calls the submodule that
+handles that particular URL type. This behavior can be the source of
+some confusion when you are providing URLs for the ``SRC_URI`` variable.
+Consider the following two URLs:
+http://git.yoctoproject.org/git/poky;protocol=git
+git://git.yoctoproject.org/git/poky;protocol=http In the former case,
+the URL is passed to the ``wget`` fetcher, which does not understand
+"git". Therefore, the latter case is the correct form since the Git
+fetcher does know how to use HTTP as a transport.
+
+Here are some examples that show commonly used mirror definitions:
+PREMIRRORS ?= "\\ bzr://.*/.\* http://somemirror.org/sources/ \\n \\
+cvs://.*/.\* http://somemirror.org/sources/ \\n \\ git://.*/.\*
+http://somemirror.org/sources/ \\n \\ hg://.*/.\*
+http://somemirror.org/sources/ \\n \\ osc://.*/.\*
+http://somemirror.org/sources/ \\n \\ p4://.*/.\*
+http://somemirror.org/sources/ \\n \\ svn://.*/.\*
+http://somemirror.org/sources/ \\n" MIRRORS =+ "\\ ftp://.*/.\*
+http://somemirror.org/sources/ \\n \\ http://.*/.\*
+http://somemirror.org/sources/ \\n \\ https://.*/.\*
+http://somemirror.org/sources/ \\n" It is useful to note that BitBake
+supports cross-URLs. It is possible to mirror a Git repository on an
+HTTP server as a tarball. This is what the ``git://`` mapping in the
+previous example does.
+
+Since network accesses are slow, BitBake maintains a cache of files
+downloaded from the network. Any source files that are not local (i.e.
+downloaded from the Internet) are placed into the download directory,
+which is specified by the ```DL_DIR`` <#var-bb-DL_DIR>`__ variable.
+
+File integrity is of key importance for reproducing builds. For
+non-local archive downloads, the fetcher code can verify SHA-256 and MD5
+checksums to ensure the archives have been downloaded correctly. You can
+specify these checksums by using the ``SRC_URI`` variable with the
+appropriate varflags as follows: SRC_URI[md5sum] = "value"
+SRC_URI[sha256sum] = "value" You can also specify the checksums as
+parameters on the ``SRC_URI`` as shown below: SRC_URI =
+"http://example.com/foobar.tar.bz2;md5sum=4a8e0f237e961fd7785d19d07fdb994d"
+If multiple URIs exist, you can specify the checksums either directly as
+in the previous example, or you can name the URLs. The following syntax
+shows how you name the URIs: SRC_URI =
+"http://example.com/foobar.tar.bz2;name=foo" SRC_URI[foo.md5sum] =
+4a8e0f237e961fd7785d19d07fdb994d After a file has been downloaded and
+has had its checksum checked, a ".done" stamp is placed in ``DL_DIR``.
+BitBake uses this stamp during subsequent builds to avoid downloading or
+comparing a checksum for the file again.
+
+.. note::
+
+   It is assumed that local storage is safe from data corruption. If
+   this were not the case, there would be bigger issues to worry about.
+
+If ```BB_STRICT_CHECKSUM`` <#var-bb-BB_STRICT_CHECKSUM>`__ is set, any
+download without a checksum triggers an error message. The
+```BB_NO_NETWORK`` <#var-bb-BB_NO_NETWORK>`__ variable can be used to
+make any attempted network access a fatal error, which is useful for
+checking that mirrors are complete as well as other things.
+
+.. _bb-the-unpack:
+
+The Unpack
+==========
+
+The unpack process usually immediately follows the download. For all
+URLs except Git URLs, BitBake uses the common ``unpack`` method.
+
+A number of parameters exist that you can specify within the URL to
+govern the behavior of the unpack stage:
+
+-  *unpack:* Controls whether the URL components are unpacked. If set to
+   "1", which is the default, the components are unpacked. If set to
+   "0", the unpack stage leaves the file alone. This parameter is useful
+   when you want an archive to be copied in and not be unpacked.
+
+-  *dos:* Applies to ``.zip`` and ``.jar`` files and specifies whether
+   to use DOS line ending conversion on text files.
+
+-  *basepath:* Instructs the unpack stage to strip the specified
+   directories from the source path when unpacking.
+
+-  *subdir:* Unpacks the specific URL to the specified subdirectory
+   within the root directory.
+
+The unpack call automatically decompresses and extracts files with ".Z",
+".z", ".gz", ".xz", ".zip", ".jar", ".ipk", ".rpm". ".srpm", ".deb" and
+".bz2" extensions as well as various combinations of tarball extensions.
+
+As mentioned, the Git fetcher has its own unpack method that is
+optimized to work with Git trees. Basically, this method works by
+cloning the tree into the final directory. The process is completed
+using references so that there is only one central copy of the Git
+metadata needed.
+
+.. _bb-fetchers:
+
+Fetchers
+========
+
+As mentioned earlier, the URL prefix determines which fetcher submodule
+BitBake uses. Each submodule can support different URL parameters, which
+are described in the following sections.
+
+.. _local-file-fetcher:
+
+Local file fetcher (``file://``)
+--------------------------------
+
+This submodule handles URLs that begin with ``file://``. The filename
+you specify within the URL can be either an absolute or relative path to
+a file. If the filename is relative, the contents of the
+```FILESPATH`` <#var-bb-FILESPATH>`__ variable is used in the same way
+``PATH`` is used to find executables. If the file cannot be found, it is
+assumed that it is available in ```DL_DIR`` <#var-bb-DL_DIR>`__ by the
+time the ``download()`` method is called.
+
+If you specify a directory, the entire directory is unpacked.
+
+Here are a couple of example URLs, the first relative and the second
+absolute: SRC_URI = "file://relativefile.patch" SRC_URI =
+"file:///Users/ich/very_important_software"
+
+.. _http-ftp-fetcher:
+
+HTTP/FTP wget fetcher (``http://``, ``ftp://``, ``https://``)
+-------------------------------------------------------------
+
+This fetcher obtains files from web and FTP servers. Internally, the
+fetcher uses the wget utility.
+
+The executable and parameters used are specified by the
+``FETCHCMD_wget`` variable, which defaults to sensible values. The
+fetcher supports a parameter "downloadfilename" that allows the name of
+the downloaded file to be specified. Specifying the name of the
+downloaded file is useful for avoiding collisions in
+```DL_DIR`` <#var-bb-DL_DIR>`__ when dealing with multiple files that
+have the same name.
+
+Some example URLs are as follows: SRC_URI =
+"http://oe.handhelds.org/not_there.aac" SRC_URI =
+"ftp://oe.handhelds.org/not_there_as_well.aac" SRC_URI =
+"ftp://you@oe.handhelds.org/home/you/secret.plan"
+
+.. note::
+
+   Because URL parameters are delimited by semi-colons, this can
+   introduce ambiguity when parsing URLs that also contain semi-colons,
+   for example:
+   ::
+
+           SRC_URI = "http://abc123.org/git/?p=gcc/gcc.git;a=snapshot;h=a5dd47"
+                      
+
+   Such URLs should should be modified by replacing semi-colons with '&'
+   characters:
+   ::
+
+           SRC_URI = "http://abc123.org/git/?p=gcc/gcc.git&a=snapshot&h=a5dd47"
+                      
+
+   In most cases this should work. Treating semi-colons and '&' in
+   queries identically is recommended by the World Wide Web Consortium
+   (W3C). Note that due to the nature of the URL, you may have to
+   specify the name of the downloaded file as well:
+   ::
+
+           SRC_URI = "http://abc123.org/git/?p=gcc/gcc.git&a=snapshot&h=a5dd47;downloadfilename=myfile.bz2"
+                      
+
+.. _cvs-fetcher:
+
+CVS fetcher (``(cvs://``)
+-------------------------
+
+This submodule handles checking out files from the CVS version control
+system. You can configure it using a number of different variables:
+
+-  *``FETCHCMD_cvs``:* The name of the executable to use when running
+   the ``cvs`` command. This name is usually "cvs".
+
+-  *``SRCDATE``:* The date to use when fetching the CVS source code. A
+   special value of "now" causes the checkout to be updated on every
+   build.
+
+-  ```CVSDIR`` <#var-bb-CVSDIR>`__\ *:* Specifies where a temporary
+   checkout is saved. The location is often ``DL_DIR/cvs``.
+
+-  *``CVS_PROXY_HOST``:* The name to use as a "proxy=" parameter to the
+   ``cvs`` command.
+
+-  *``CVS_PROXY_PORT``:* The port number to use as a "proxyport="
+   parameter to the ``cvs`` command.
+
+As well as the standard username and password URL syntax, you can also
+configure the fetcher with various URL parameters:
+
+The supported parameters are as follows:
+
+-  *"method":* The protocol over which to communicate with the CVS
+   server. By default, this protocol is "pserver". If "method" is set to
+   "ext", BitBake examines the "rsh" parameter and sets ``CVS_RSH``. You
+   can use "dir" for local directories.
+
+-  *"module":* Specifies the module to check out. You must supply this
+   parameter.
+
+-  *"tag":* Describes which CVS TAG should be used for the checkout. By
+   default, the TAG is empty.
+
+-  *"date":* Specifies a date. If no "date" is specified, the
+   ```SRCDATE`` <#var-bb-SRCDATE>`__ of the configuration is used to
+   checkout a specific date. The special value of "now" causes the
+   checkout to be updated on every build.
+
+-  *"localdir":* Used to rename the module. Effectively, you are
+   renaming the output directory to which the module is unpacked. You
+   are forcing the module into a special directory relative to
+   ```CVSDIR`` <#var-bb-CVSDIR>`__.
+
+-  *"rsh"* Used in conjunction with the "method" parameter.
+
+-  *"scmdata":* Causes the CVS metadata to be maintained in the tarball
+   the fetcher creates when set to "keep". The tarball is expanded into
+   the work directory. By default, the CVS metadata is removed.
+
+-  *"fullpath":* Controls whether the resulting checkout is at the
+   module level, which is the default, or is at deeper paths.
+
+-  *"norecurse":* Causes the fetcher to only checkout the specified
+   directory with no recurse into any subdirectories.
+
+-  *"port":* The port to which the CVS server connects.
+
+Some example URLs are as follows: SRC_URI =
+"cvs://CVSROOT;module=mymodule;tag=some-version;method=ext" SRC_URI =
+"cvs://CVSROOT;module=mymodule;date=20060126;localdir=usethat"
+
+.. _svn-fetcher:
+
+Subversion (SVN) Fetcher (``svn://``)
+-------------------------------------
+
+This fetcher submodule fetches code from the Subversion source control
+system. The executable used is specified by ``FETCHCMD_svn``, which
+defaults to "svn". The fetcher's temporary working directory is set by
+```SVNDIR`` <#var-bb-SVNDIR>`__, which is usually ``DL_DIR/svn``.
+
+The supported parameters are as follows:
+
+-  *"module":* The name of the svn module to checkout. You must provide
+   this parameter. You can think of this parameter as the top-level
+   directory of the repository data you want.
+
+-  *"path_spec":* A specific directory in which to checkout the
+   specified svn module.
+
+-  *"protocol":* The protocol to use, which defaults to "svn". If
+   "protocol" is set to "svn+ssh", the "ssh" parameter is also used.
+
+-  *"rev":* The revision of the source code to checkout.
+
+-  *"scmdata":* Causes the “.svn” directories to be available during
+   compile-time when set to "keep". By default, these directories are
+   removed.
+
+-  *"ssh":* An optional parameter used when "protocol" is set to
+   "svn+ssh". You can use this parameter to specify the ssh program used
+   by svn.
+
+-  *"transportuser":* When required, sets the username for the
+   transport. By default, this parameter is empty. The transport
+   username is different than the username used in the main URL, which
+   is passed to the subversion command.
+
+Following are three examples using svn: SRC_URI =
+"svn://myrepos/proj1;module=vip;protocol=http;rev=667" SRC_URI =
+"svn://myrepos/proj1;module=opie;protocol=svn+ssh" SRC_URI =
+"svn://myrepos/proj1;module=trunk;protocol=http;path_spec=${MY_DIR}/proj1"
+
+.. _git-fetcher:
+
+Git Fetcher (``git://``)
+------------------------
+
+This fetcher submodule fetches code from the Git source control system.
+The fetcher works by creating a bare clone of the remote into
+```GITDIR`` <#var-bb-GITDIR>`__, which is usually ``DL_DIR/git2``. This
+bare clone is then cloned into the work directory during the unpack
+stage when a specific tree is checked out. This is done using alternates
+and by reference to minimize the amount of duplicate data on the disk
+and make the unpack process fast. The executable used can be set with
+``FETCHCMD_git``.
+
+This fetcher supports the following parameters:
+
+-  *"protocol":* The protocol used to fetch the files. The default is
+   "git" when a hostname is set. If a hostname is not set, the Git
+   protocol is "file". You can also use "http", "https", "ssh" and
+   "rsync".
+
+-  *"nocheckout":* Tells the fetcher to not checkout source code when
+   unpacking when set to "1". Set this option for the URL where there is
+   a custom routine to checkout code. The default is "0".
+
+-  *"rebaseable":* Indicates that the upstream Git repository can be
+   rebased. You should set this parameter to "1" if revisions can become
+   detached from branches. In this case, the source mirror tarball is
+   done per revision, which has a loss of efficiency. Rebasing the
+   upstream Git repository could cause the current revision to disappear
+   from the upstream repository. This option reminds the fetcher to
+   preserve the local cache carefully for future use. The default value
+   for this parameter is "0".
+
+-  *"nobranch":* Tells the fetcher to not check the SHA validation for
+   the branch when set to "1". The default is "0". Set this option for
+   the recipe that refers to the commit that is valid for a tag instead
+   of the branch.
+
+-  *"bareclone":* Tells the fetcher to clone a bare clone into the
+   destination directory without checking out a working tree. Only the
+   raw Git metadata is provided. This parameter implies the "nocheckout"
+   parameter as well.
+
+-  *"branch":* The branch(es) of the Git tree to clone. If unset, this
+   is assumed to be "master". The number of branch parameters much match
+   the number of name parameters.
+
+-  *"rev":* The revision to use for the checkout. The default is
+   "master".
+
+-  *"tag":* Specifies a tag to use for the checkout. To correctly
+   resolve tags, BitBake must access the network. For that reason, tags
+   are often not used. As far as Git is concerned, the "tag" parameter
+   behaves effectively the same as the "rev" parameter.
+
+-  *"subpath":* Limits the checkout to a specific subpath of the tree.
+   By default, the whole tree is checked out.
+
+-  *"destsuffix":* The name of the path in which to place the checkout.
+   By default, the path is ``git/``.
+
+-  *"usehead":* Enables local ``git://`` URLs to use the current branch
+   HEAD as the revision for use with ``AUTOREV``. The "usehead"
+   parameter implies no branch and only works when the transfer protocol
+   is ``file://``.
+
+Here are some example URLs: SRC_URI =
+"git://git.oe.handhelds.org/git/vip.git;tag=version-1" SRC_URI =
+"git://git.oe.handhelds.org/git/vip.git;protocol=http"
+
+.. _gitsm-fetcher:
+
+Git Submodule Fetcher (``gitsm://``)
+------------------------------------
+
+This fetcher submodule inherits from the `Git fetcher <#git-fetcher>`__
+and extends that fetcher's behavior by fetching a repository's
+submodules. ```SRC_URI`` <#var-bb-SRC_URI>`__ is passed to the Git
+fetcher as described in the "`Git Fetcher
+(``git://``) <#git-fetcher>`__" section.
+
+.. note::
+
+   You must clean a recipe when switching between '``git://``' and
+   '``gitsm://``' URLs.
+
+   The Git Submodules fetcher is not a complete fetcher implementation.
+   The fetcher has known issues where it does not use the normal source
+   mirroring infrastructure properly. Further, the submodule sources it
+   fetches are not visible to the licensing and source archiving
+   infrastructures.
+
+.. _clearcase-fetcher:
+
+ClearCase Fetcher (``ccrc://``)
+-------------------------------
+
+This fetcher submodule fetches code from a
+`ClearCase <http://en.wikipedia.org/wiki/Rational_ClearCase>`__
+repository.
+
+To use this fetcher, make sure your recipe has proper
+```SRC_URI`` <#var-bb-SRC_URI>`__, ```SRCREV`` <#var-bb-SRCREV>`__, and
+```PV`` <#var-bb-PV>`__ settings. Here is an example: SRC_URI =
+"ccrc://cc.example.org/ccrc;vob=/example_vob;module=/example_module"
+SRCREV = "EXAMPLE_CLEARCASE_TAG" PV = "${@d.getVar("SRCREV",
+False).replace("/", "+")}" The fetcher uses the ``rcleartool`` or
+``cleartool`` remote client, depending on which one is available.
+
+Following are options for the ``SRC_URI`` statement:
+
+-  *``vob``*: The name, which must include the prepending "/" character,
+   of the ClearCase VOB. This option is required.
+
+-  *``module``*: The module, which must include the prepending "/"
+   character, in the selected VOB.
+
+   .. note::
+
+      The
+      module
+      and
+      vob
+      options are combined to create the
+      load
+      rule in the view config spec. As an example, consider the
+      vob
+      and
+      module
+      values from the
+      SRC_URI
+      statement at the start of this section. Combining those values
+      results in the following:
+      ::
+
+              load /example_vob/example_module
+                                     
+
+-  *``proto``*: The protocol, which can be either ``http`` or ``https``.
+
+By default, the fetcher creates a configuration specification. If you
+want this specification written to an area other than the default, use
+the ``CCASE_CUSTOM_CONFIG_SPEC`` variable in your recipe to define where
+the specification is written.
+
+.. note::
+
+   the
+   SRCREV
+   loses its functionality if you specify this variable. However,
+   SRCREV
+   is still used to label the archive after a fetch even though it does
+   not define what is fetched.
+
+Here are a couple of other behaviors worth mentioning:
+
+-  When using ``cleartool``, the login of ``cleartool`` is handled by
+   the system. The login require no special steps.
+
+-  In order to use ``rcleartool`` with authenticated users, an
+   "rcleartool login" is necessary before using the fetcher.
+
+.. _perforce-fetcher:
+
+Perforce Fetcher (``p4://``)
+----------------------------
+
+This fetcher submodule fetches code from the
+`Perforce <https://www.perforce.com/>`__ source control system. The
+executable used is specified by ``FETCHCMD_p4``, which defaults to "p4".
+The fetcher's temporary working directory is set by
+```P4DIR`` <#var-bb-P4DIR>`__, which defaults to "DL_DIR/p4".
+The fetcher does not make use of a perforce client, instead it
+relies on ``p4 files`` to retrieve a list of
+files and ``p4 print`` to transfer the content
+of those files locally.
+
+To use this fetcher, make sure your recipe has proper
+```SRC_URI`` <#var-bb-SRC_URI>`__, ```SRCREV`` <#var-bb-SRCREV>`__, and
+```PV`` <#var-bb-PV>`__ values. The p4 executable is able to use the
+config file defined by your system's ``P4CONFIG`` environment variable
+in order to define the Perforce server URL and port, username, and
+password if you do not wish to keep those values in a recipe itself. If
+you choose not to use ``P4CONFIG``, or to explicitly set variables that
+``P4CONFIG`` can contain, you can specify the ``P4PORT`` value, which is
+the server's URL and port number, and you can specify a username and
+password directly in your recipe within ``SRC_URI``.
+
+Here is an example that relies on ``P4CONFIG`` to specify the server URL
+and port, username, and password, and fetches the Head Revision: SRC_URI
+= "p4://example-depot/main/source/..." SRCREV = "${AUTOREV}" PV =
+"p4-${SRCPV}" S = "${WORKDIR}/p4"
+
+Here is an example that specifies the server URL and port, username, and
+password, and fetches a Revision based on a Label: P4PORT =
+"tcp:p4server.example.net:1666" SRC_URI =
+"p4://user:passwd@example-depot/main/source/..." SRCREV = "release-1.0"
+PV = "p4-${SRCPV}" S = "${WORKDIR}/p4"
+
+.. note::
+
+   You should always set
+   S
+   to
+   "${WORKDIR}/p4"
+   in your recipe.
+
+By default, the fetcher strips the depot location from the local file paths. In
+the above example, the content of ``example-depot/main/source/`` will be placed
+in ``${WORKDIR}/p4``.  For situations where preserving parts of the remote depot
+paths locally is desirable, the fetcher supports two parameters:
+
+- **"module":**
+    The top-level depot location or directory to fetch. The value of this
+    parameter can also point to a single file within the depot, in which case
+    the local file path will include the module path.
+- **"remotepath":**
+    When used with the value "``keep``", the fetcher will mirror the full depot
+    paths locally for the specified location, even in combination with the
+    ``module`` parameter.
+
+Here is an example use of the the ``module`` parameter: ::
+
+   SRC_URI = "p4://user:passwd@example-depot/main;module=source/..."
+
+In this case, the content of the top-level directory ``source/`` will be fetched
+to ``${P4DIR}``, including the directory itself.  The top-level directory will
+be accesible at ``${P4DIR}/source/``.
+
+Here is an example use of the the ``remotepath`` parameter: ::
+
+   SRC_URI = "p4://user:passwd@example-depot/main;module=source/...;remotepath=keep"
+
+In this case, the content of the top-level directory ``source/`` will be fetched
+to ``${P4DIR}``, but the complete depot paths will be mirrored locally. The
+top-level directory will be accessible at
+``${P4DIR}/example-depot/main/source/``.
+
+.. _repo-fetcher:
+
+Repo Fetcher (``repo://``)
+--------------------------
+
+This fetcher submodule fetches code from ``google-repo`` source control
+system. The fetcher works by initiating and syncing sources of the
+repository into ```REPODIR`` <#var-bb-REPODIR>`__, which is usually
+```DL_DIR`` <#var-bb-DL_DIR>`__\ ``/repo``.
+
+This fetcher supports the following parameters:
+
+-  *"protocol":* Protocol to fetch the repository manifest (default:
+   git).
+
+-  *"branch":* Branch or tag of repository to get (default: master).
+
+-  *"manifest":* Name of the manifest file (default: ``default.xml``).
+
+Here are some example URLs: SRC_URI =
+"repo://REPOROOT;protocol=git;branch=some_branch;manifest=my_manifest.xml"
+SRC_URI =
+"repo://REPOROOT;protocol=file;branch=some_branch;manifest=my_manifest.xml"
+
+Other Fetchers
+--------------
+
+Fetch submodules also exist for the following:
+
+-  Bazaar (``bzr://``)
+
+-  Mercurial (``hg://``)
+
+-  npm (``npm://``)
+
+-  OSC (``osc://``)
+
+-  Secure FTP (``sftp://``)
+
+-  Secure Shell (``ssh://``)
+
+-  Trees using Git Annex (``gitannex://``)
+
+No documentation currently exists for these lesser used fetcher
+submodules. However, you might find the code helpful and readable.
+
+Auto Revisions
+==============
+
+We need to document ``AUTOREV`` and ``SRCREV_FORMAT`` here.