build/package.gni - fuchsia - Git at Google

 # Copyright 2017 The Fuchsia Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.

 import("//build/images/args.gni")
 import("//build/images/manifest.gni")
 import("//build/testing/test_spec.gni")
 import("//src/sys/cmc/build/cml.gni")
 import("//src/sys/cmc/build/cmx.gni")
 import("//src/sys/component_index/component_index.gni")
 import("//src/sys/pkg/bin/pm/pm.gni")

 # Defines a package
 #
 # The package template is used to define a unit of related code and data.
 # A package always has a name (defaulting to the target name) and lists of
 # scopes describing the components of the package.
 #
 # Parameters
 #
 #   meta (optional)
 #     [list of scopes] Defines the metadata entries in the package. A metadata
 #     entry is typically a source file and is placed in the `meta/` directory of
 #     the assembled package.
 #
 #     Entries in a scope in the meta list:
 #
 #       path (required)
 #         [path] Location of entry in source or build directory. If the
 #         resource is checked in, this will typically be specified as a
 #         path relative to the BUILD.gn file containing the `package()`
 #         target. If the resource is generated, this will typically be
 #         specified relative to `$target_gen_dir`.
 #
 #       dest (required)
 #         [path] Location the resource will be placed within `meta/`.
 #
 #   binary (optional, *DEPRECATED*)
 #     [string] The path to the primary binary for the package, relative to
 #     `$root_out_dir`. The binary will be placed in the assembled package at
 #     `bin/app` and will be executed by default when running the package.
 #
 #   binaries (optional)
 #     [list of scopes] Defines the binaries in the package. A binary is
 #     typically produced by the build system and is placed in the `bin/`
 #     directory of the assembled package.
 #
 #     Entries in a scope in the binaries list:
 #
 #       name (required)
 #         [string] Name of the binary.
 #
 #       source (optional)
 #         [path] Location of the binary in the build directory if it is not
 #         at `$root_out_dir/$name`.
 #
 #       dest (optional)
 #         [path] Location the binary will be placed within `bin/`.
 #
 #       shell (optional)
 #         [boolean] (default: false) When true, the binary is runnable from the shell.
 #         Shell binaries are run in the shell namespace and are not run as components.
 #
 #   tests (optional)
 #     [list of scopes] Defines the test binaries in the package. A test is
 #     typically produced by the build system and is placed in the `test/`
 #     directory of the assembled package.
 #
 #     Entries in a scope in the tests list:
 #
 #       name (required)
 #         [string] Name of the test.
 #
 #       dest (optional, default: name)
 #         [path] Location the binary will be placed within `test/`.
 #
 #       disabled (optional)
 #         [bool] Whether to disable the test on continuous integration
 #         jobs. This can be used when a test is temporarily broken, or if
 #         it is too flaky or slow for CI. The test will also be skipped by
 #         the `runtests` command.
 #
 #       environments (optional, default: [ { dimensions = { device_type = "QEMU" } } ])
 #         [list of scopes] Device environments in which the test should run.
 #
 #         Each scope in $environments contains:
 #
 #           dimensions (required)
 #             [scope] Dimensions of bots to target. Valid dimensions are
 #             element-wise subsets of the test platform entries defined in
 #             //build/testing/platforms.gni.
 #
 #           tags (optional)
 #             [list of strings] Keys on which tests may be grouped. Tests with
 #             given keys will be run (1) together, and (2) only with support
 #             from the Infrastructure team. Labels are used as an escape hatch
 #             from the default testing pipeline for special tests or environments.
 #
 #   drivers (optional)
 #     [list of scopes] Defines the drivers in the package. A driver is
 #     typically produced by the build system and is placed in the `driver/`
 #     directory of the assembled package.
 #
 #     Entries in a scope in the drivers list:
 #
 #       name (required)
 #         [string] Name of the driver.
 #
 #   loadable_modules (optional)
 #     [list of scopes] Defines the loadable modules in the package.  These
 #     are produced by `loadable_module()` GN targets, and are typically
 #     placed in the `lib/` directory of the assembled packaged.
 #
 #     Entries in a scope in the loadable_modules list:
 #
 #       name (required)
 #         [string] Name of the loadable_module.
 #
 #       dest (optional, default: "lib")
 #         [string] Location the binary will be placed in the package.
 #
 #   libraries (optional, *DEPRECATED*)
 #     [list of scopes] Defines the (shared) libraries in the package. A library
 #     is placed in the `lib/` directory of the assembled package.
 #
 #     This is deprecated but is necessary in some `system_image` packages
 #     that install libraries used by things that don't properly isolate
 #     their dependencies.  Do not use it unless you are sure you have to.
 #
 #     Entries in a scope in the libraries list:
 #
 #       name (required)
 #         [string] Name of the library
 #
 #       source (optional)
 #         [path] Location of the binary in the build directory if it is not at
 #         `$root_out_dir/$name`
 #
 #       dest (optional)
 #         [path] Location the binary will be placed within `lib/`
 #
 #   resources (optional)
 #     [list of scopes] Defines the resources in the package. A resource is a
 #     data file that may be produced by the build system, checked in to a
 #     source repository, or produced by another system that runs before the
 #     build. Resources are placed in the `data/` directory of the assembled
 #     package.
 #
 #     Entries in a scope in the resources list:
 #
 #       path (required)
 #         [path] Location of resource in source or build directory. If the
 #         resource is checked in, this will typically be specified as a
 #         path relative to the BUILD.gn file containing the `package()`
 #         target. If the resource is generated, this will typically be
 #         specified relative to `$target_gen_dir`.
 #
 #       dest (required)
 #         [path] Location the resource will be placed within `data/`.
 #
 #   extra (optional)
 #     [list of paths] Manifest files containing extra entries, which
 #     might be generated by the build.
 #
 #   deps (optional)
 #   public_deps (optional)
 #   data_deps (optional)
 #   testonly (optional)
 #     Usual GN meanings.
 #
 template("package") {
   if (current_toolchain == target_toolchain) {
     forward_variables_from(invoker, [ "testonly" ])
     pkg_target_name = target_name
     pkg = {
       package_version = "0"  # placeholder
       forward_variables_from(
           invoker,
           [
             "binaries",
             "binary",
             "data_deps",
             "deprecated_system_image",  # TODO(bwb) remove after soft-transition
             "__deprecated_system_image",
             "deps",
             "public_deps",
             "drivers",
             "extra",
             "libraries",
             "loadable_modules",
             "meta",
             "package_name",
             "resources",
             "visibility",
             "tests",
           ])
       if (!defined(binaries)) {
         binaries = []
       }
       if (!defined(__deprecated_system_image) &&
           !defined(deprecated_system_image)) {
         __deprecated_system_image = false
       }
       if (defined(deprecated_system_image)) {
         __deprecated_system_image = deprecated_system_image
       }
       if (!defined(deps)) {
         deps = []
       }
       if (!defined(data_deps)) {
         data_deps = []
       }
       if (!defined(public_deps)) {
         public_deps = []
       }
       if (!defined(extra)) {
         extra = []
       }
       if (!defined(drivers)) {
         drivers = []
       }
       if (!defined(loadable_modules)) {
         loadable_modules = []
       }
       if (!defined(libraries)) {
         libraries = []
       }
       if (!defined(meta)) {
         meta = []
       }
       if (!defined(package_name)) {
         package_name = pkg_target_name
       }
       if (!defined(resources)) {
         resources = []
       }
       if (!defined(tests)) {
         tests = []
       }
     }

     assert(pkg.package_name != "tests" && pkg.package_name != "app" &&
                pkg.package_name != "bin" && pkg.package_name != "pkg" &&
                pkg.package_name != "lib" && pkg.package_name != "package" &&
                pkg.package_name != "binary" && pkg.package_name != "service" &&
                pkg.package_name != "svc" && pkg.package_name != "component",
            "${pkg.package_name} is too generic a name for a package")

     pkg_label = get_label_info(":$pkg_target_name", "label_no_toolchain")
     pkg_desc = "Package ${pkg_label} (${pkg.package_name}):"
     if (pkg.__deprecated_system_image) {
       assert(
           pkg.meta == [],
           "$pkg_desc __deprecated_system_image (likely from driver_package) incompatible with meta")
       assert(
           !defined(pkg.binary),
           "$pkg_desc __deprecated_system_image (likely from driver_package) incompatible with binary")

       # Only appmgr can contribute binaries to /system/bin.
       assert(pkg.binaries == [] || pkg.package_name == "appmgr",
              "no new packages are allowed to add binaries to /system/bin")

       assert(pkg.tests == [], "tests are not allowed in /system")
     } else {
       assert(pkg.drivers == [],
              "$pkg_desc drivers requires __deprecated_system_image")
       assert(pkg.libraries == [],
              "$pkg_desc libraries requires __deprecated_system_image")
       if (defined(pkg.binary)) {
         pkg.binaries += [
           {
             name = "app"
             source = pkg.binary
           },
         ]
       }
     }

     formatted_manifest = []
     foreach(meta, pkg.meta) {
       manifest_target = pkg_target_name + "_" + get_path_info(meta.dest, "file")

       if (get_path_info(meta.dest, "extension") == "cmx") {
         cmx(manifest_target) {
           manifest = meta.path
           forward_variables_from(pkg,
                                  [
                                    "deps",
                                    "testonly",
                                  ])
         }

         component_index_target = "${manifest_target}_component_index"
         add_to_component_index(component_index_target) {
           package_name = pkg.package_name
           manifest = "meta/${meta.dest}"
         }
         pkg.deps += [ ":$component_index_target" ]
       } else if (get_path_info(meta.path, "extension") == "cml") {
         cm(manifest_target) {
           manifest = meta.path
           forward_variables_from(pkg,
                                  [
                                    "deps",
                                    "testonly",
                                  ])
         }
       }

       manifest_output = []
       manifest_output = get_target_outputs(":$manifest_target")
       meta.path = manifest_output[0]
       pkg.deps += [ ":$manifest_target" ]
       formatted_manifest += [ meta ]
     }

     # Collect the package's primary manifest.  For a system_image package,
     # this is its contributions to the /system manifest.  For an isolated
     # package, this is the manifest for the package's `pkg/` filesystem.
     pkg_manifest = []
     foreach(meta, formatted_manifest) {
       pkg_manifest += [
         {
           dest = "meta/${meta.dest}"
           source = rebase_path(meta.path)
         },
       ]
     }
     shell_binaries = []
     foreach(binary, pkg.binaries) {
       if (defined(binary.dest)) {
         dest = binary.dest
       } else {
         dest = binary.name
       }
       dest = "bin/${dest}"

       if (defined(binary.shell) && binary.shell) {
         shellfile = target_gen_dir + "/" + dest + ".shell"
         write_file(
             shellfile,
             [ "#!resolve fuchsia-pkg://fuchsia.com/${pkg.package_name}#${dest}" ])
         shell_binaries +=
             [ "${dest}=" + rebase_path(shellfile, root_build_dir) ]

         # The shell environment is not intended for production use.
         pkg.deps += [ "//build/validate:non_production_tag" ]
       }

       pkg_manifest += [
         {
           dest = dest

           if (defined(binary.source)) {
             source = binary.source
           } else {
             source = binary.name
           }
           source = rebase_path(source, "", root_out_dir)
         },
       ]
     }

     foreach(test, pkg.tests) {
       assert(!defined(test.tags),
              "tags are only valid within an environment scope")

       # It's a common mistake to specify "tags" in the scope of the test
       # instead of in an environment scope.
       is_disabled = defined(test.disabled) && test.disabled

       if (defined(test.dest)) {
         dest = test.dest
       } else {
         dest = test.name
       }
       if (is_disabled) {
         dest = "disabled/${dest}"
       }

       if (bootfs_only) {
         dest = "test/sys/$dest"
         path = "/boot/$dest"
       } else {
         url = "fuchsia-pkg://fuchsia.com"
         dest = "test/$dest"
         if (pkg.__deprecated_system_image) {
           url_pkg_name = "system"
           path = "/system/$dest"
         } else {
           url_pkg_name = pkg.package_name
           path = ""
         }
         url += "/${url_pkg_name}"
       }

       dest_name = get_path_info(dest, "name")
       not_needed([ "dest_name" ])

       # Check that all tests are components with cmx/cm files at the expected path.
       if (!pkg.__deprecated_system_image && !bootfs_only && !is_disabled &&
           (!defined(require_bare_tests_allowlist) ||
            !require_bare_tests_allowlist)) {
         require_bare_tests_allowlist = true
         url_resource_path = ""
         foreach(meta, pkg.meta) {
           extension = get_path_info(meta.dest, "extension")
           if (extension == "cmx" || extension == "cm") {
             meta_name = get_path_info(meta.dest, "name")
             if (dest_name == meta_name) {
               require_bare_tests_allowlist = false
               url_resource_path = "#meta/${meta.dest}"
             }
           }
         }
         url += url_resource_path
       }

       if (!is_disabled) {
         test_spec_name = "${pkg.package_name}_${dest}_test_spec"
         pkg.deps += [ ":$test_spec_name" ]

         test_spec(test_spec_name) {
           target = ":${invoker.target_name}"
           path = path
           if (!bootfs_only) {
             package_url = url
           }
           forward_variables_from(test, [ "environments" ])
         }
       } else {
         not_needed([
                      "path",
                      "url",
                    ])
       }

       pkg_manifest += [
         {
           dest = dest
           source = rebase_path(test.name, "", root_out_dir)
         },
       ]
     }

     foreach(module, pkg.loadable_modules) {
       pkg_manifest += [
         {
           if (defined(module.dest)) {
             dest = module.dest
           } else {
             dest = "lib"
           }
           dest += "/${module.name}"
           source = rebase_path(module.name, "", root_out_dir)
         },
       ]
     }
     foreach(driver, pkg.drivers) {
       pkg_manifest += [
         {
           dest = "driver/${driver.name}"
           source = rebase_path(driver.name, "", root_out_dir)
         },
       ]
     }
     foreach(resource, pkg.resources) {
       pkg_manifest += [
         {
           dest = "data/${resource.dest}"
           source = rebase_path(resource.path)
         },
       ]
     }

     # TODO(mcgrathr): Remove this when we can!  Packages installing
     # libraries in the system image is all kinds of wrong.
     foreach(library, pkg.libraries) {
       pkg_manifest += [
         {
           if (defined(library.dest)) {
             dest = library.dest
           } else {
             dest = library.name
           }
           dest = "lib/${dest}"
           if (defined(library.source)) {
             source = library.source
           } else {
             # TODO(mcgrathr): This breaks when everything is a variant so
             # that only this here is using the non-variant shlib build.
             source = get_label_info(shlib_toolchain, "name")
             source += "/${library.name}"
           }
           source = rebase_path(source, "", root_out_dir)
         },
       ]
     }

     # Collect all the arguments describing input manifest files
     # and all the entries we've just synthesized in `pkg_manifest`.
     manifest_sources = pkg.extra
     manifest_args = []
     foreach(manifest_file, pkg.extra) {
       manifest_file = rebase_path(manifest_file, root_build_dir)
       manifest_args += [ "--manifest=${manifest_file}" ]
     }
     manifest_args += [ "--entry-manifest=${pkg_label}" ]
     foreach(entry, pkg_manifest) {
       manifest_sources += [ entry.source ]
       manifest_args += [ "--entry=${entry.dest}=${entry.source}" ]
     }

     pkg.metadata = {
       if (defined(invoker.metadata)) {
         forward_variables_from(invoker.metadata, "*")
       }
       shell_binary_entries = shell_binaries
     }

     if (defined(pkg.visibility)) {
       pkg.visibility += [
         ":$target_name",

         # TODO(raggi): tighten build/images visibility once we've
         # finished doing large scale cleanups.
         "//build/images:*",
         "//build/packages/*",
         "//bundles/*",
         "//garnet/packages/*",
         "//src/modular/bundles/*",
         "//topaz/packages/*",
         "//vendor/*",
       ]
     }

     # An empty package() target doesn't actually generate a package at all.
     # Conveniently, an empty system_image package has exactly that effect.
     if (manifest_sources == []) {
       pkg.__deprecated_system_image = true
     }

     if (pkg.__deprecated_system_image || bootfs_only) {
       system_rsp_label = pkg_target_name + ".system.rsp"

       # System image packages just donate manifest arguments
       generate_response_file(system_rsp_label) {
         if (defined(pkg.visibility)) {
           visibility = pkg.visibility
         }
         deps = pkg.deps
         data_deps = pkg.data_deps
         public_deps = pkg.public_deps
         output_name = "${pkg_target_name}.system.rsp"
         response_file_contents = manifest_args
         metadata = {
           forward_variables_from(pkg.metadata, "*")

           system_image_rsps = [ "@" +
                                 rebase_path(target_out_dir + "/" + output_name,
                                             root_build_dir) ]

           system_image_barrier = []
         }
       }
       not_needed([ "component_indices" ])
     }

     # Synthesize the meta/package file.
     pkg_meta_generated = "${pkg_target_name}_meta_package.json"
     pkg_meta_output = "$target_out_dir/${pkg_target_name}_meta_package.json"
     generated_file(pkg_meta_generated) {
       contents = "{\"name\":\"${pkg.package_name}\",\"version\":\"${pkg.package_version}\"}"
       outputs = [ pkg_meta_output ]
       output_conversion = "string"
     }

     # Fuchsia package aggregates a manifest from its arguments and builds a
     # metadata archive.
     manifest = "${pkg_target_name}.manifest"
     generate_manifest(manifest) {
       visibility = [ ":" + pkg_target_name ]
       sources = manifest_sources + [ pkg_meta_output ]
       args =
           manifest_args + [ "--entry=meta/package=" +
                             rebase_path(pkg_meta_output, "", target_out_dir) ]
       deps = pkg.deps + [ ":$pkg_meta_generated" ]
       public_deps = pkg.public_deps
     }

     # Next generate a sealed package file.
     pm_build(pkg_target_name) {
       if (defined(pkg.visibility)) {
         visibility = pkg.visibility
       }
       package_name = pkg.package_name
       manifest = ":$manifest"
       metadata = {
         forward_variables_from(pkg.metadata, "*")
       }

       deps = pkg.deps
       data_deps = pkg.data_deps
       public_deps = pkg.public_deps

       if (pkg.__deprecated_system_image || bootfs_only) {
         public_deps += [ ":" + system_rsp_label ]
       }

       # Add the dep on the allowlist here rather than in pkg.deps earlier so that we can allow
       # specific targets by the package target's name using visibility.
       if (defined(require_bare_tests_allowlist) &&
           require_bare_tests_allowlist) {
         deps += [ "//build:deprecated_bare_tests_allowlist" ]
       }
     }
   } else {
     # A reference from a different toolchain, e.g. a variant toolchain, is
     # just an indirect way to get the package into the system images.
     # Redirect it as data_deps on the $target_toolchain package.  This
     # really ought to be a pure redirect, i.e. public_deps.  But using
     # data_deps here avoids problems in case some dependency on a package()
     # target is not in data_deps as it (almost surely) should be.
     group(target_name) {
       forward_variables_from(invoker,
                              [
                                "visibility",
                                "testonly",
                              ])
       data_deps = [ ":$target_name($target_toolchain)" ]
     }

     # Suppress unused variable warnings.
     not_needed(invoker, "*")
   }
 }
	# Copyright 2017 The Fuchsia Authors. All rights reserved.
	# Use of this source code is governed by a BSD-style license that can be
	# found in the LICENSE file.

	import("//build/images/args.gni")
	import("//build/images/manifest.gni")
	import("//build/testing/test_spec.gni")
	import("//src/sys/cmc/build/cml.gni")
	import("//src/sys/cmc/build/cmx.gni")
	import("//src/sys/component_index/component_index.gni")
	import("//src/sys/pkg/bin/pm/pm.gni")

	# Defines a package
	#
	# The package template is used to define a unit of related code and data.
	# A package always has a name (defaulting to the target name) and lists of
	# scopes describing the components of the package.
	#
	# Parameters
	#
	# meta (optional)
	# [list of scopes] Defines the metadata entries in the package. A metadata
	# entry is typically a source file and is placed in the `meta/` directory of
	# the assembled package.
	#
	# Entries in a scope in the meta list:
	#
	# path (required)
	# [path] Location of entry in source or build directory. If the
	# resource is checked in, this will typically be specified as a
	# path relative to the BUILD.gn file containing the `package()`
	# target. If the resource is generated, this will typically be
	# specified relative to `$target_gen_dir`.
	#
	# dest (required)
	# [path] Location the resource will be placed within `meta/`.
	#
	# binary (optional, DEPRECATED)
	# [string] The path to the primary binary for the package, relative to
	# `$root_out_dir`. The binary will be placed in the assembled package at
	# `bin/app` and will be executed by default when running the package.
	#
	# binaries (optional)
	# [list of scopes] Defines the binaries in the package. A binary is
	# typically produced by the build system and is placed in the `bin/`
	# directory of the assembled package.
	#
	# Entries in a scope in the binaries list:
	#
	# name (required)
	# [string] Name of the binary.
	#
	# source (optional)
	# [path] Location of the binary in the build directory if it is not
	# at `$root_out_dir/$name`.
	#
	# dest (optional)
	# [path] Location the binary will be placed within `bin/`.
	#
	# shell (optional)
	# [boolean] (default: false) When true, the binary is runnable from the shell.
	# Shell binaries are run in the shell namespace and are not run as components.
	#
	# tests (optional)
	# [list of scopes] Defines the test binaries in the package. A test is
	# typically produced by the build system and is placed in the `test/`
	# directory of the assembled package.
	#
	# Entries in a scope in the tests list:
	#
	# name (required)
	# [string] Name of the test.
	#
	# dest (optional, default: name)
	# [path] Location the binary will be placed within `test/`.
	#
	# disabled (optional)
	# [bool] Whether to disable the test on continuous integration
	# jobs. This can be used when a test is temporarily broken, or if
	# it is too flaky or slow for CI. The test will also be skipped by
	# the `runtests` command.
	#
	# environments (optional, default: [ { dimensions = { device_type = "QEMU" } } ])
	# [list of scopes] Device environments in which the test should run.
	#
	# Each scope in $environments contains:
	#
	# dimensions (required)
	# [scope] Dimensions of bots to target. Valid dimensions are
	# element-wise subsets of the test platform entries defined in
	# //build/testing/platforms.gni.
	#
	# tags (optional)
	# [list of strings] Keys on which tests may be grouped. Tests with
	# given keys will be run (1) together, and (2) only with support
	# from the Infrastructure team. Labels are used as an escape hatch
	# from the default testing pipeline for special tests or environments.
	#
	# drivers (optional)
	# [list of scopes] Defines the drivers in the package. A driver is
	# typically produced by the build system and is placed in the `driver/`
	# directory of the assembled package.
	#
	# Entries in a scope in the drivers list:
	#
	# name (required)
	# [string] Name of the driver.
	#
	# loadable_modules (optional)
	# [list of scopes] Defines the loadable modules in the package. These
	# are produced by `loadable_module()` GN targets, and are typically
	# placed in the `lib/` directory of the assembled packaged.
	#
	# Entries in a scope in the loadable_modules list:
	#
	# name (required)
	# [string] Name of the loadable_module.
	#
	# dest (optional, default: "lib")
	# [string] Location the binary will be placed in the package.
	#
	# libraries (optional, DEPRECATED)
	# [list of scopes] Defines the (shared) libraries in the package. A library
	# is placed in the `lib/` directory of the assembled package.
	#
	# This is deprecated but is necessary in some `system_image` packages
	# that install libraries used by things that don't properly isolate
	# their dependencies. Do not use it unless you are sure you have to.
	#
	# Entries in a scope in the libraries list:
	#
	# name (required)
	# [string] Name of the library
	#
	# source (optional)
	# [path] Location of the binary in the build directory if it is not at
	# `$root_out_dir/$name`
	#
	# dest (optional)
	# [path] Location the binary will be placed within `lib/`
	#
	# resources (optional)
	# [list of scopes] Defines the resources in the package. A resource is a
	# data file that may be produced by the build system, checked in to a
	# source repository, or produced by another system that runs before the
	# build. Resources are placed in the `data/` directory of the assembled
	# package.
	#
	# Entries in a scope in the resources list:
	#
	# path (required)
	# [path] Location of resource in source or build directory. If the
	# resource is checked in, this will typically be specified as a
	# path relative to the BUILD.gn file containing the `package()`
	# target. If the resource is generated, this will typically be
	# specified relative to `$target_gen_dir`.
	#
	# dest (required)
	# [path] Location the resource will be placed within `data/`.
	#
	# extra (optional)
	# [list of paths] Manifest files containing extra entries, which
	# might be generated by the build.
	#
	# deps (optional)
	# public_deps (optional)
	# data_deps (optional)
	# testonly (optional)
	# Usual GN meanings.
	#
	template("package") {
	if (current_toolchain == target_toolchain) {
	forward_variables_from(invoker, [ "testonly" ])
	pkg_target_name = target_name
	pkg = {
	package_version = "0" # placeholder
	forward_variables_from(
	invoker,
	[
	"binaries",
	"binary",
	"data_deps",
	"deprecated_system_image", # TODO(bwb) remove after soft-transition
	"__deprecated_system_image",
	"deps",
	"public_deps",
	"drivers",
	"extra",
	"libraries",
	"loadable_modules",
	"meta",
	"package_name",
	"resources",
	"visibility",
	"tests",
	])
	if (!defined(binaries)) {
	binaries = []
	}
	if (!defined(__deprecated_system_image) &&
	!defined(deprecated_system_image)) {
	__deprecated_system_image = false
	}
	if (defined(deprecated_system_image)) {
	__deprecated_system_image = deprecated_system_image
	}
	if (!defined(deps)) {
	deps = []
	}
	if (!defined(data_deps)) {
	data_deps = []
	}
	if (!defined(public_deps)) {
	public_deps = []
	}
	if (!defined(extra)) {
	extra = []
	}
	if (!defined(drivers)) {
	drivers = []
	}
	if (!defined(loadable_modules)) {
	loadable_modules = []
	}
	if (!defined(libraries)) {
	libraries = []
	}
	if (!defined(meta)) {
	meta = []
	}
	if (!defined(package_name)) {
	package_name = pkg_target_name
	}
	if (!defined(resources)) {
	resources = []
	}
	if (!defined(tests)) {
	tests = []
	}
	}

	assert(pkg.package_name != "tests" && pkg.package_name != "app" &&
	pkg.package_name != "bin" && pkg.package_name != "pkg" &&
	pkg.package_name != "lib" && pkg.package_name != "package" &&
	pkg.package_name != "binary" && pkg.package_name != "service" &&
	pkg.package_name != "svc" && pkg.package_name != "component",
	"${pkg.package_name} is too generic a name for a package")

	pkg_label = get_label_info(":$pkg_target_name", "label_no_toolchain")
	pkg_desc = "Package ${pkg_label} (${pkg.package_name}):"
	if (pkg.__deprecated_system_image) {
	assert(
	pkg.meta == [],
	"$pkg_desc __deprecated_system_image (likely from driver_package) incompatible with meta")
	assert(
	!defined(pkg.binary),
	"$pkg_desc __deprecated_system_image (likely from driver_package) incompatible with binary")

	# Only appmgr can contribute binaries to /system/bin.
	assert(pkg.binaries == [] \|\| pkg.package_name == "appmgr",
	"no new packages are allowed to add binaries to /system/bin")

	assert(pkg.tests == [], "tests are not allowed in /system")
	} else {
	assert(pkg.drivers == [],
	"$pkg_desc drivers requires __deprecated_system_image")
	assert(pkg.libraries == [],
	"$pkg_desc libraries requires __deprecated_system_image")
	if (defined(pkg.binary)) {
	pkg.binaries += [
	{
	name = "app"
	source = pkg.binary
	},
	]
	}
	}

	formatted_manifest = []
	foreach(meta, pkg.meta) {
	manifest_target = pkg_target_name + "_" + get_path_info(meta.dest, "file")

	if (get_path_info(meta.dest, "extension") == "cmx") {
	cmx(manifest_target) {
	manifest = meta.path
	forward_variables_from(pkg,
	[
	"deps",
	"testonly",
	])
	}

	component_index_target = "${manifest_target}_component_index"
	add_to_component_index(component_index_target) {
	package_name = pkg.package_name
	manifest = "meta/${meta.dest}"
	}
	pkg.deps += [ ":$component_index_target" ]
	} else if (get_path_info(meta.path, "extension") == "cml") {
	cm(manifest_target) {
	manifest = meta.path
	forward_variables_from(pkg,
	[
	"deps",
	"testonly",
	])
	}
	}

	manifest_output = []
	manifest_output = get_target_outputs(":$manifest_target")
	meta.path = manifest_output[0]
	pkg.deps += [ ":$manifest_target" ]
	formatted_manifest += [ meta ]
	}

	# Collect the package's primary manifest. For a system_image package,
	# this is its contributions to the /system manifest. For an isolated
	# package, this is the manifest for the package's `pkg/` filesystem.
	pkg_manifest = []
	foreach(meta, formatted_manifest) {
	pkg_manifest += [
	{
	dest = "meta/${meta.dest}"
	source = rebase_path(meta.path)
	},
	]
	}
	shell_binaries = []
	foreach(binary, pkg.binaries) {
	if (defined(binary.dest)) {
	dest = binary.dest
	} else {
	dest = binary.name
	}
	dest = "bin/${dest}"

	if (defined(binary.shell) && binary.shell) {
	shellfile = target_gen_dir + "/" + dest + ".shell"
	write_file(
	shellfile,
	[ "#!resolve fuchsia-pkg://fuchsia.com/${pkg.package_name}#${dest}" ])
	shell_binaries +=
	[ "${dest}=" + rebase_path(shellfile, root_build_dir) ]

	# The shell environment is not intended for production use.
	pkg.deps += [ "//build/validate:non_production_tag" ]
	}

	pkg_manifest += [
	{
	dest = dest

	if (defined(binary.source)) {
	source = binary.source
	} else {
	source = binary.name
	}
	source = rebase_path(source, "", root_out_dir)
	},
	]
	}

	foreach(test, pkg.tests) {
	assert(!defined(test.tags),
	"tags are only valid within an environment scope")

	# It's a common mistake to specify "tags" in the scope of the test
	# instead of in an environment scope.
	is_disabled = defined(test.disabled) && test.disabled

	if (defined(test.dest)) {
	dest = test.dest
	} else {
	dest = test.name
	}
	if (is_disabled) {
	dest = "disabled/${dest}"
	}

	if (bootfs_only) {
	dest = "test/sys/$dest"
	path = "/boot/$dest"
	} else {
	url = "fuchsia-pkg://fuchsia.com"
	dest = "test/$dest"
	if (pkg.__deprecated_system_image) {
	url_pkg_name = "system"
	path = "/system/$dest"
	} else {
	url_pkg_name = pkg.package_name
	path = ""
	}
	url += "/${url_pkg_name}"
	}

	dest_name = get_path_info(dest, "name")
	not_needed([ "dest_name" ])

	# Check that all tests are components with cmx/cm files at the expected path.
	if (!pkg.__deprecated_system_image && !bootfs_only && !is_disabled &&
	(!defined(require_bare_tests_allowlist) \|\|
	!require_bare_tests_allowlist)) {
	require_bare_tests_allowlist = true
	url_resource_path = ""
	foreach(meta, pkg.meta) {
	extension = get_path_info(meta.dest, "extension")
	if (extension == "cmx" \|\| extension == "cm") {
	meta_name = get_path_info(meta.dest, "name")
	if (dest_name == meta_name) {
	require_bare_tests_allowlist = false
	url_resource_path = "#meta/${meta.dest}"
	}
	}
	}
	url += url_resource_path
	}

	if (!is_disabled) {
	test_spec_name = "${pkg.package_name}_${dest}_test_spec"
	pkg.deps += [ ":$test_spec_name" ]

	test_spec(test_spec_name) {
	target = ":${invoker.target_name}"
	path = path
	if (!bootfs_only) {
	package_url = url
	}
	forward_variables_from(test, [ "environments" ])
	}
	} else {
	not_needed([
	"path",
	"url",
	])
	}

	pkg_manifest += [
	{
	dest = dest
	source = rebase_path(test.name, "", root_out_dir)
	},
	]
	}

	foreach(module, pkg.loadable_modules) {
	pkg_manifest += [
	{
	if (defined(module.dest)) {
	dest = module.dest
	} else {
	dest = "lib"
	}
	dest += "/${module.name}"
	source = rebase_path(module.name, "", root_out_dir)
	},
	]
	}
	foreach(driver, pkg.drivers) {
	pkg_manifest += [
	{
	dest = "driver/${driver.name}"
	source = rebase_path(driver.name, "", root_out_dir)
	},
	]
	}
	foreach(resource, pkg.resources) {
	pkg_manifest += [
	{
	dest = "data/${resource.dest}"
	source = rebase_path(resource.path)
	},
	]
	}

	# TODO(mcgrathr): Remove this when we can! Packages installing
	# libraries in the system image is all kinds of wrong.
	foreach(library, pkg.libraries) {
	pkg_manifest += [
	{
	if (defined(library.dest)) {
	dest = library.dest
	} else {
	dest = library.name
	}
	dest = "lib/${dest}"
	if (defined(library.source)) {
	source = library.source
	} else {
	# TODO(mcgrathr): This breaks when everything is a variant so
	# that only this here is using the non-variant shlib build.
	source = get_label_info(shlib_toolchain, "name")
	source += "/${library.name}"
	}
	source = rebase_path(source, "", root_out_dir)
	},
	]
	}

	# Collect all the arguments describing input manifest files
	# and all the entries we've just synthesized in `pkg_manifest`.
	manifest_sources = pkg.extra
	manifest_args = []
	foreach(manifest_file, pkg.extra) {
	manifest_file = rebase_path(manifest_file, root_build_dir)
	manifest_args += [ "--manifest=${manifest_file}" ]
	}
	manifest_args += [ "--entry-manifest=${pkg_label}" ]
	foreach(entry, pkg_manifest) {
	manifest_sources += [ entry.source ]
	manifest_args += [ "--entry=${entry.dest}=${entry.source}" ]
	}

	pkg.metadata = {
	if (defined(invoker.metadata)) {
	forward_variables_from(invoker.metadata, "*")
	}
	shell_binary_entries = shell_binaries
	}

	if (defined(pkg.visibility)) {
	pkg.visibility += [
	":$target_name",

	# TODO(raggi): tighten build/images visibility once we've
	# finished doing large scale cleanups.
	"//build/images:*",
	"//build/packages/*",
	"//bundles/*",
	"//garnet/packages/*",
	"//src/modular/bundles/*",
	"//topaz/packages/*",
	"//vendor/*",
	]
	}

	# An empty package() target doesn't actually generate a package at all.
	# Conveniently, an empty system_image package has exactly that effect.
	if (manifest_sources == []) {
	pkg.__deprecated_system_image = true
	}

	if (pkg.__deprecated_system_image \|\| bootfs_only) {
	system_rsp_label = pkg_target_name + ".system.rsp"

	# System image packages just donate manifest arguments
	generate_response_file(system_rsp_label) {
	if (defined(pkg.visibility)) {
	visibility = pkg.visibility
	}
	deps = pkg.deps
	data_deps = pkg.data_deps
	public_deps = pkg.public_deps
	output_name = "${pkg_target_name}.system.rsp"
	response_file_contents = manifest_args
	metadata = {
	forward_variables_from(pkg.metadata, "*")

	system_image_rsps = [ "@" +
	rebase_path(target_out_dir + "/" + output_name,
	root_build_dir) ]

	system_image_barrier = []
	}
	}
	not_needed([ "component_indices" ])
	}

	# Synthesize the meta/package file.
	pkg_meta_generated = "${pkg_target_name}_meta_package.json"
	pkg_meta_output = "$target_out_dir/${pkg_target_name}_meta_package.json"
	generated_file(pkg_meta_generated) {
	contents = "{\"name\":\"${pkg.package_name}\",\"version\":\"${pkg.package_version}\"}"
	outputs = [ pkg_meta_output ]
	output_conversion = "string"
	}

	# Fuchsia package aggregates a manifest from its arguments and builds a
	# metadata archive.
	manifest = "${pkg_target_name}.manifest"
	generate_manifest(manifest) {
	visibility = [ ":" + pkg_target_name ]
	sources = manifest_sources + [ pkg_meta_output ]
	args =
	manifest_args + [ "--entry=meta/package=" +
	rebase_path(pkg_meta_output, "", target_out_dir) ]
	deps = pkg.deps + [ ":$pkg_meta_generated" ]
	public_deps = pkg.public_deps
	}

	# Next generate a sealed package file.
	pm_build(pkg_target_name) {
	if (defined(pkg.visibility)) {
	visibility = pkg.visibility
	}
	package_name = pkg.package_name
	manifest = ":$manifest"
	metadata = {
	forward_variables_from(pkg.metadata, "*")
	}

	deps = pkg.deps
	data_deps = pkg.data_deps
	public_deps = pkg.public_deps

	if (pkg.__deprecated_system_image \|\| bootfs_only) {
	public_deps += [ ":" + system_rsp_label ]
	}

	# Add the dep on the allowlist here rather than in pkg.deps earlier so that we can allow
	# specific targets by the package target's name using visibility.
	if (defined(require_bare_tests_allowlist) &&
	require_bare_tests_allowlist) {
	deps += [ "//build:deprecated_bare_tests_allowlist" ]
	}
	}
	} else {
	# A reference from a different toolchain, e.g. a variant toolchain, is
	# just an indirect way to get the package into the system images.
	# Redirect it as data_deps on the $target_toolchain package. This
	# really ought to be a pure redirect, i.e. public_deps. But using
	# data_deps here avoids problems in case some dependency on a package()
	# target is not in data_deps as it (almost surely) should be.
	group(target_name) {
	forward_variables_from(invoker,
	[
	"visibility",
	"testonly",
	])
	data_deps = [ ":$target_name($target_toolchain)" ]
	}

	# Suppress unused variable warnings.
	not_needed(invoker, "*")
	}
	}