michael@0: .. _jar_manifests:
michael@0: 
michael@0: =============
michael@0: JAR Manifests
michael@0: =============
michael@0: 
michael@0: JAR Manifests are plaintext files in the tree that are used to package chrome
michael@0: files into the correct JARs, and create
michael@0: `Chrome Registration <https://developer.mozilla.org/en-US/docs/Chrome_Registration>`_
michael@0: manifests. JAR Manifests are commonly named ``jar.mn``. They are
michael@0: declared in ``moz.build`` files using the ``JAR_MANIFESTS`` variable.
michael@0: 
michael@0: ``jar.mn`` files are automatically processed by the build system when building a
michael@0: source directory that contains one. The ``jar``.mn is run through the
michael@0: :ref:`preprocessor` before being passed to the manifest processor. In order to
michael@0: have ``@variables@`` expanded (such as ``@AB_CD@``) throughout the file, add
michael@0: the line ``#filter substitution`` at the top of your ``jar.mn`` file.
michael@0: 
michael@0: The format of a jar.mn is fairly simple; it consists of a heading specifying
michael@0: which JAR file is being packaged, followed by indented lines listing files and
michael@0: chrome registration instructions.
michael@0: 
michael@0: To see a simple ``jar.mn`` file at work, see ``toolkit/profile/jar.mn``. A much
michael@0: more complex ``jar.mn`` is at ``toolkit/locales/jar.mn``.
michael@0: 
michael@0: Shipping Chrome Files
michael@0: =====================
michael@0: 
michael@0: To ship chrome files in a JAR, an indented line indicates a file to be packaged::
michael@0: 
michael@0:    <jarfile>.jar:
michael@0:      path/in/jar/file_name.xul     (source/tree/location/file_name.xul)
michael@0: 
michael@0: The source tree location may also be an *absolute* path (taken from the
michael@0: top of the source tree::
michael@0: 
michael@0:    path/in/jar/file_name.xul     (/path/in/sourcetree/file_name.xul)
michael@0: 
michael@0: An asterisk marker (``*``) at the beginning of the line indicates that the
michael@0: file should be processed by the :ref:`preprocessor` before being packaged::
michael@0: 
michael@0:    * path/in/jar/preprocessed.xul  (source/tree/location/file_name.xul)
michael@0: 
michael@0: A plus marker (``+``) at the beginning of the line indicates that the file
michael@0: should replace an existing file, even if the source file's timestamp isn't
michael@0: newer than the existing file::
michael@0: 
michael@0:    + path/in/jar/file_name.xul     (source/tree/location/my_file_name.xul)
michael@0: 
michael@0: Preprocessed files always replace existing files, to ensure that changes in
michael@0: ``#expand`` or ``#include`` directives are picked up, so ``+`` and ``*`` are
michael@0: equivalent.
michael@0: 
michael@0: There is a special source-directory format for localized files (note the
michael@0: percent sign in the source file location): this format reads ``localized.dtd``
michael@0: from the ``en-US`` directory if building an English version, and reads the
michael@0: file from the alternate localization source tree
michael@0: ``/l10n/<locale>/path/localized.dtd`` if building a localized version::
michael@0: 
michael@0:    locale/path/localized.dtd     (%localized/path/localized.dtd)
michael@0: 
michael@0: Register Chrome
michael@0: ===============
michael@0: 
michael@0: `Chrome Registration <https://developer.mozilla.org/en-US/docs/Chrome_Registration>`_
michael@0: instructions are marked with a percent sign (``%``) at the beginning of the
michael@0: line, and must be part of the definition of a JAR file. Any additional percents
michael@0: signs are replaced with an appropriate relative URL of the JAR file being
michael@0: packaged::
michael@0: 
michael@0:    % content global %path/in/jar/
michael@0:    % overlay chrome://blah/content/blah.xul chrome://foo/content/overlay.xul
michael@0: 
michael@0: There are two possible locations for a manifest file. If the chrome is being
michael@0: built into a standalone application, the ``jar.mn`` processor creates a
michael@0: ``<jarfilename>.manifest`` next to the JAR file itself. This is the default
michael@0: behavior.
michael@0: 
michael@0: If the build specifies ``USE_EXTENSION_MANIFEST = 1``, the ``jar.mn`` processor
michael@0: creates a single ``chrome.manifest`` file suitable for registering chrome as
michael@0: an extension.