Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1206 insertions, 0 deletions

diff --git a/xpcom/components/gen_static_components.py b/xpcom/components/gen_static_components.py
new file mode 100644
index 0000000000..3d73eda603
--- /dev/null
+++ b/xpcom/components/gen_static_components.py
@@ -0,0 +1,1206 @@
+import json
+import os
+import re
+import struct
+from collections import defaultdict
+from uuid import UUID
+
+import buildconfig
+from mozbuild.util import FileAvoidWrite
+from perfecthash import PerfectHash
+
+NO_CONTRACT_ID = 0xFFFFFFFF
+
+PHF_SIZE = 512
+
+TINY_PHF_SIZE = 16
+
+# In tests, we might not have a (complete) buildconfig.
+ENDIAN = (
+    "<" if buildconfig.substs.get("TARGET_ENDIANNESS", "little") == "little" else ">"
+)
+
+
+# Represents a UUID in the format used internally by Gecko, and supports
+# serializing it in that format to both C++ source and raw byte arrays.
+class UUIDRepr(object):
+    def __init__(self, uuid):
+        self.uuid = uuid
+
+        fields = uuid.fields
+
+        self.a = fields[0]
+        self.b = fields[1]
+        self.c = fields[2]
+
+        d = list(fields[3:5])
+        for i in range(0, 6):
+            d.append(fields[5] >> (8 * (5 - i)) & 0xFF)
+
+        self.d = tuple(d)
+
+    def __str__(self):
+        return str(self.uuid)
+
+    @property
+    def bytes(self):
+        return struct.pack(ENDIAN + "IHHBBBBBBBB", self.a, self.b, self.c, *self.d)
+
+    def to_cxx(self):
+        rest = ", ".join("0x%02x" % b for b in self.d)
+
+        return "{ 0x%x, 0x%x, 0x%x, { %s } }" % (self.a, self.b, self.c, rest)
+
+
+# Corresponds to the Module::ProcessSelector enum in Module.h. The actual
+# values don't matter, since the code generator emits symbolic constants for
+# these values, but we use the same values as the enum constants for clarity.
+class ProcessSelector:
+    ANY_PROCESS = 0x0
+    MAIN_PROCESS_ONLY = 0x1
+    CONTENT_PROCESS_ONLY = 0x2
+    ALLOW_IN_GPU_PROCESS = 0x4
+    ALLOW_IN_VR_PROCESS = 0x8
+    ALLOW_IN_SOCKET_PROCESS = 0x10
+    ALLOW_IN_RDD_PROCESS = 0x20
+    ALLOW_IN_UTILITY_PROCESS = 0x30
+    ALLOW_IN_GPU_AND_MAIN_PROCESS = ALLOW_IN_GPU_PROCESS | MAIN_PROCESS_ONLY
+    ALLOW_IN_GPU_AND_SOCKET_PROCESS = ALLOW_IN_GPU_PROCESS | ALLOW_IN_SOCKET_PROCESS
+    ALLOW_IN_GPU_AND_VR_PROCESS = ALLOW_IN_GPU_PROCESS | ALLOW_IN_VR_PROCESS
+    ALLOW_IN_GPU_VR_AND_SOCKET_PROCESS = (
+        ALLOW_IN_GPU_PROCESS | ALLOW_IN_VR_PROCESS | ALLOW_IN_SOCKET_PROCESS
+    )
+    ALLOW_IN_RDD_AND_SOCKET_PROCESS = ALLOW_IN_RDD_PROCESS | ALLOW_IN_SOCKET_PROCESS
+    ALLOW_IN_GPU_RDD_AND_SOCKET_PROCESS = (
+        ALLOW_IN_GPU_PROCESS | ALLOW_IN_RDD_PROCESS | ALLOW_IN_SOCKET_PROCESS
+    )
+    ALLOW_IN_GPU_RDD_SOCKET_AND_UTILITY_PROCESS = (
+        ALLOW_IN_GPU_PROCESS
+        | ALLOW_IN_RDD_PROCESS
+        | ALLOW_IN_SOCKET_PROCESS
+        | ALLOW_IN_UTILITY_PROCESS
+    )
+    ALLOW_IN_GPU_RDD_VR_AND_SOCKET_PROCESS = (
+        ALLOW_IN_GPU_PROCESS
+        | ALLOW_IN_RDD_PROCESS
+        | ALLOW_IN_VR_PROCESS
+        | ALLOW_IN_SOCKET_PROCESS
+    )
+    ALLOW_IN_GPU_RDD_VR_SOCKET_AND_UTILITY_PROCESS = (
+        ALLOW_IN_GPU_PROCESS
+        | ALLOW_IN_RDD_PROCESS
+        | ALLOW_IN_VR_PROCESS
+        | ALLOW_IN_SOCKET_PROCESS
+        | ALLOW_IN_UTILITY_PROCESS
+    )
+
+
+# Maps ProcessSelector constants to the name of the corresponding
+# Module::ProcessSelector enum value.
+PROCESSES = {
+    ProcessSelector.ANY_PROCESS: "ANY_PROCESS",
+    ProcessSelector.MAIN_PROCESS_ONLY: "MAIN_PROCESS_ONLY",
+    ProcessSelector.CONTENT_PROCESS_ONLY: "CONTENT_PROCESS_ONLY",
+    ProcessSelector.ALLOW_IN_GPU_PROCESS: "ALLOW_IN_GPU_PROCESS",
+    ProcessSelector.ALLOW_IN_VR_PROCESS: "ALLOW_IN_VR_PROCESS",
+    ProcessSelector.ALLOW_IN_SOCKET_PROCESS: "ALLOW_IN_SOCKET_PROCESS",
+    ProcessSelector.ALLOW_IN_RDD_PROCESS: "ALLOW_IN_RDD_PROCESS",
+    ProcessSelector.ALLOW_IN_GPU_AND_MAIN_PROCESS: "ALLOW_IN_GPU_AND_MAIN_PROCESS",
+    ProcessSelector.ALLOW_IN_GPU_AND_SOCKET_PROCESS: "ALLOW_IN_GPU_AND_SOCKET_PROCESS",
+    ProcessSelector.ALLOW_IN_GPU_AND_VR_PROCESS: "ALLOW_IN_GPU_AND_VR_PROCESS",
+    ProcessSelector.ALLOW_IN_GPU_VR_AND_SOCKET_PROCESS: "ALLOW_IN_GPU_VR_AND_SOCKET_PROCESS",
+    ProcessSelector.ALLOW_IN_RDD_AND_SOCKET_PROCESS: "ALLOW_IN_RDD_AND_SOCKET_PROCESS",
+    ProcessSelector.ALLOW_IN_GPU_RDD_AND_SOCKET_PROCESS: "ALLOW_IN_GPU_RDD_AND_SOCKET_PROCESS",
+    ProcessSelector.ALLOW_IN_GPU_RDD_SOCKET_AND_UTILITY_PROCESS: "ALLOW_IN_GPU_RDD_SOCKET_AND_UTILITY_PROCESS",  # NOQA: E501
+    ProcessSelector.ALLOW_IN_GPU_RDD_VR_AND_SOCKET_PROCESS: "ALLOW_IN_GPU_RDD_VR_AND_SOCKET_PROCESS",  # NOQA: E501
+    ProcessSelector.ALLOW_IN_GPU_RDD_VR_SOCKET_AND_UTILITY_PROCESS: "ALLOW_IN_GPU_RDD_VR_SOCKET_AND_UTILITY_PROCESS",  # NOQA: E501
+}
+
+
+# Emits the C++ symbolic constant corresponding to a ProcessSelector constant.
+def lower_processes(processes):
+    return "Module::ProcessSelector::%s" % PROCESSES[processes]
+
+
+# Emits the C++ symbolic constant for a ModuleEntry's ModuleID enum entry.
+def lower_module_id(module):
+    return "ModuleID::%s" % module.name
+
+
+# Corresponds to the Module::BackgroundTasksSelector enum in Module.h. The
+# actual values don't matter, since the code generator emits symbolic constants
+# for these values, but we use the same values as the enum constants for
+# clarity.
+class BackgroundTasksSelector:
+    NO_TASKS = 0x0
+    ALL_TASKS = 0xFFFF
+
+
+# Maps BackgroundTasksSelector constants to the name of the corresponding
+# Module::BackgroundTasksSelector enum value.
+BACKGROUNDTASKS = {
+    BackgroundTasksSelector.ALL_TASKS: "ALL_TASKS",
+    BackgroundTasksSelector.NO_TASKS: "NO_TASKS",
+}
+
+
+# Emits the C++ symbolic constant corresponding to a BackgroundTasks constant.
+def lower_backgroundtasks(backgroundtasks):
+    return "Module::BackgroundTasksSelector::%s" % BACKGROUNDTASKS[backgroundtasks]
+
+
+# Represents a static string table, indexed by offset. This allows us to
+# reference strings from static data structures without requiring runtime
+# relocations.
+class StringTable(object):
+    def __init__(self):
+        self.entries = {}
+        self.entry_list = []
+        self.size = 0
+
+        self._serialized = False
+
+    # Returns the index of the given string in the `entry_list` array. If
+    # no entry for the string exists, it first creates one.
+    def get_idx(self, string):
+        idx = self.entries.get(string, None)
+        if idx is not None:
+            return idx
+
+        assert not self._serialized
+
+        assert len(string) == len(string.encode("utf-8"))
+
+        idx = self.size
+        self.size += len(string) + 1
+
+        self.entries[string] = idx
+        self.entry_list.append(string)
+        return idx
+
+    # Returns the C++ code representing string data of this string table, as a
+    # single string literal. This must only be called after the last call to
+    # `get_idx()` or `entry_to_cxx()` for this instance.
+    def to_cxx(self):
+        self._serialized = True
+
+        lines = []
+
+        idx = 0
+        for entry in self.entry_list:
+            str_ = entry.replace("\\", "\\\\").replace('"', r"\"").replace("\n", r"\n")
+
+            lines.append('    /* 0x%x */ "%s\\0"\n' % (idx, str_))
+
+            idx += len(entry) + 1
+
+        return "".join(lines)
+
+    # Returns a `StringEntry` struct initializer for the string table entry
+    # corresponding to the given string. If no matching entry exists, it is
+    # first created.
+    def entry_to_cxx(self, string):
+        idx = self.get_idx(string)
+        return "{ 0x%x } /* %s */" % (idx, pretty_string(string))
+
+
+strings = StringTable()
+
+interfaces = []
+
+
+# Represents a C++ namespace, containing a set of classes and potentially
+# sub-namespaces. This is used to generate pre-declarations for incomplete
+# types referenced in XPCOM manifests.
+class Namespace(object):
+    def __init__(self, name=None):
+        self.name = name
+        self.classes = set()
+        self.namespaces = {}
+
+    # Returns a Namespace object for the sub-namespace with the given name.
+    def sub(self, name):
+        assert name not in self.classes
+
+        if name not in self.namespaces:
+            self.namespaces[name] = Namespace(name)
+        return self.namespaces[name]
+
+    # Generates C++ code to pre-declare all classes in this namespace and all
+    # of its sub-namespaces.
+    def to_cxx(self):
+        res = ""
+        if self.name:
+            res += "namespace %s {\n" % self.name
+
+        for clas in sorted(self.classes):
+            res += "class %s;\n" % clas
+
+        for ns in sorted(self.namespaces.keys()):
+            res += self.namespaces[ns].to_cxx()
+
+        if self.name:
+            res += "}  // namespace %s\n" % self.name
+
+        return res
+
+
+# Represents a component defined in an XPCOM manifest's `Classes` array.
+class ModuleEntry(object):
+    next_anon_id = 0
+
+    def __init__(self, data, init_idx):
+        self.cid = UUIDRepr(UUID(data["cid"]))
+        self.contract_ids = data.get("contract_ids", [])
+        self.type = data.get("type", "nsISupports")
+        self.categories = data.get("categories", {})
+        self.processes = data.get("processes", 0)
+        self.headers = data.get("headers", [])
+
+        self.js_name = data.get("js_name", None)
+        self.interfaces = data.get("interfaces", [])
+
+        if len(self.interfaces) > 255:
+            raise Exception(
+                "JS service %s may not have more than 255 " "interfaces" % self.js_name
+            )
+
+        self.interfaces_offset = len(interfaces)
+        for iface in self.interfaces:
+            interfaces.append(iface)
+
+        # If the manifest declares Init or Unload functions, this contains its
+        # index, as understood by the `CallInitFunc()` function.
+        #
+        # If it contains any value other than `None`, a corresponding
+        # `CallInitFunc(init_idx)` call will be genrated before calling this
+        # module's constructor.
+        self.init_idx = init_idx
+
+        self.constructor = data.get("constructor", None)
+        self.legacy_constructor = data.get("legacy_constructor", None)
+        self.init_method = data.get("init_method", [])
+
+        self.jsm = data.get("jsm", None)
+        self.esModule = data.get("esModule", None)
+
+        self.external = data.get(
+            "external", not (self.headers or self.legacy_constructor)
+        )
+        self.singleton = data.get("singleton", False)
+        self.overridable = data.get("overridable", False)
+
+        self.protocol_config = data.get("protocol_config", None)
+
+        if "name" in data:
+            self.anonymous = False
+            self.name = data["name"]
+        else:
+            self.anonymous = True
+            self.name = "Anonymous%03d" % ModuleEntry.next_anon_id
+            ModuleEntry.next_anon_id += 1
+
+        def error(str_):
+            raise Exception(
+                "Error defining component %s (%s): %s"
+                % (str(self.cid), ", ".join(map(repr, self.contract_ids)), str_)
+            )
+
+        if self.jsm:
+            if not self.constructor:
+                error("JavaScript components must specify a constructor")
+
+            for prop in ("init_method", "legacy_constructor", "headers"):
+                if getattr(self, prop):
+                    error(
+                        "JavaScript components may not specify a '%s' "
+                        "property" % prop
+                    )
+        elif self.esModule:
+            if not self.constructor:
+                error("JavaScript components must specify a constructor")
+
+            for prop in ("init_method", "legacy_constructor", "headers"):
+                if getattr(self, prop):
+                    error(
+                        "JavaScript components may not specify a '%s' "
+                        "property" % prop
+                    )
+        elif self.external:
+            if self.constructor or self.legacy_constructor:
+                error(
+                    "Externally-constructed components may not specify "
+                    "'constructor' or 'legacy_constructor' properties"
+                )
+            if self.init_method:
+                error(
+                    "Externally-constructed components may not specify "
+                    "'init_method' properties"
+                )
+            if self.type == "nsISupports":
+                error(
+                    "Externally-constructed components must specify a type "
+                    "other than nsISupports"
+                )
+
+        if self.constructor and self.legacy_constructor:
+            error(
+                "The 'constructor' and 'legacy_constructor' properties "
+                "are mutually exclusive"
+            )
+
+        if self.overridable and not self.contract_ids:
+            error("Overridable components must specify at least one contract " "ID")
+
+    @property
+    def contract_id(self):
+        return self.contract_ids[0]
+
+    # Generates the C++ code for a StaticModule struct initializer
+    # representing this component.
+    def to_cxx(self):
+        contract_id = (
+            strings.entry_to_cxx(self.contract_id)
+            if self.overridable
+            else "{ 0x%x }" % NO_CONTRACT_ID
+        )
+
+        return """
+        /* {name} */ {{
+          /* {{{cid_string}}} */
+          {cid},
+          {contract_id},
+          {processes},
+        }}""".format(
+            name=self.name,
+            cid=self.cid.to_cxx(),
+            cid_string=str(self.cid),
+            contract_id=contract_id,
+            processes=lower_processes(self.processes),
+        )
+
+    # Generates the C++ code for a JSServiceEntry representing this module.
+    def lower_js_service(self):
+        return """
+        {{
+          {js_name},
+          ModuleID::{name},
+          {{ {iface_offset} }},
+          {iface_count}
+        }}""".format(
+            js_name=strings.entry_to_cxx(self.js_name),
+            name=self.name,
+            iface_offset=self.interfaces_offset,
+            iface_count=len(self.interfaces),
+        )
+
+    # Generates the C++ code necessary to construct an instance of this
+    # component.
+    #
+    # This code lives in a function with the following arguments:
+    #
+    #  - aIID: The `const nsIID&` interface ID that the resulting instance
+    #          will be queried to.
+    #
+    #  - aResult: The `void**` pointer in which to store the result.
+    #
+    # And which returns an `nsresult` indicating success or failure.
+    def lower_constructor(self):
+        res = ""
+
+        if self.init_idx is not None:
+            res += "      MOZ_TRY(CallInitFunc(%d));\n" % self.init_idx
+
+        if self.legacy_constructor:
+            res += (
+                "      return /* legacy */ %s(aIID, aResult);\n"
+                % self.legacy_constructor
+            )
+            return res
+
+        if self.jsm:
+            res += (
+                "      nsCOMPtr<nsISupports> inst;\n"
+                "      MOZ_TRY(ConstructJSMComponent(nsLiteralCString(%s),\n"
+                "                                    %s,\n"
+                "                                    getter_AddRefs(inst)));"
+                "\n" % (json.dumps(self.jsm), json.dumps(self.constructor))
+            )
+        elif self.esModule:
+            res += (
+                "      nsCOMPtr<nsISupports> inst;\n"
+                "      MOZ_TRY(ConstructESModuleComponent(nsLiteralCString(%s),\n"
+                "                                         %s,\n"
+                "                                         getter_AddRefs(inst)));"
+                "\n" % (json.dumps(self.esModule), json.dumps(self.constructor))
+            )
+        elif self.external:
+            res += (
+                "      nsCOMPtr<nsISupports> inst = "
+                "mozCreateComponent<%s>();\n" % self.type
+            )
+            # The custom constructor may return null, so check before calling
+            # any methods.
+            res += "      NS_ENSURE_TRUE(inst, NS_ERROR_FAILURE);\n"
+        else:
+            res += "      RefPtr<%s> inst = " % self.type
+
+            if not self.constructor:
+                res += "new %s();\n" % self.type
+            else:
+                res += "%s();\n" % self.constructor
+                # The `new` operator is infallible, so we don't need to worry
+                # about it returning null, but custom constructors may, so
+                # check before calling any methods.
+                res += "      NS_ENSURE_TRUE(inst, NS_ERROR_OUT_OF_MEMORY);\n"
+
+                # Check that the constructor function returns an appropriate
+                # `already_AddRefed` value for our declared type.
+                res += """
+      using T =
+          RemoveAlreadyAddRefed<decltype(%(constructor)s())>::Type;
+      static_assert(
+          std::is_same_v<already_AddRefed<T>, decltype(%(constructor)s())>,
+          "Singleton constructor must return already_AddRefed");
+      static_assert(
+          std::is_base_of<%(type)s, T>::value,
+          "Singleton constructor must return correct already_AddRefed");
+
+""" % {
+                    "type": self.type,
+                    "constructor": self.constructor,
+                }
+
+            if self.init_method:
+                res += "      MOZ_TRY(inst->%s());\n" % self.init_method
+
+        res += "      return inst->QueryInterface(aIID, aResult);\n"
+
+        return res
+
+    # Generates the C++ code for the `mozilla::components::<name>` entry
+    # corresponding to this component. This may not be called for modules
+    # without an explicit `name` (in which cases, `self.anonymous` will be
+    # true).
+    def lower_getters(self):
+        assert not self.anonymous
+
+        substs = {
+            "name": self.name,
+            "id": "::mozilla::xpcom::ModuleID::%s" % self.name,
+        }
+
+        res = (
+            """
+namespace %(name)s {
+static inline const nsID& CID() {
+  return ::mozilla::xpcom::Components::GetCID(%(id)s);
+}
+
+static inline ::mozilla::xpcom::GetServiceHelper Service(nsresult* aRv = nullptr) {
+  return {%(id)s, aRv};
+}
+"""
+            % substs
+        )
+
+        if not self.singleton:
+            res += (
+                """
+static inline ::mozilla::xpcom::CreateInstanceHelper Create(nsresult* aRv = nullptr) {
+  return {%(id)s, aRv};
+}
+"""
+                % substs
+            )
+
+        res += (
+            """\
+}  // namespace %(name)s
+"""
+            % substs
+        )
+
+        return res
+
+    # Generates the rust code for the `xpcom::components::<name>` entry
+    # corresponding to this component. This may not be called for modules
+    # without an explicit `name` (in which cases, `self.anonymous` will be
+    # true).
+    def lower_getters_rust(self):
+        assert not self.anonymous
+
+        substs = {
+            "name": self.name,
+            "id": "super::ModuleID::%s" % self.name,
+        }
+
+        res = (
+            """
+#[allow(non_snake_case)]
+pub mod %(name)s {
+    /// Get the singleton service instance for this component.
+    pub fn service<T: crate::XpCom>() -> Result<crate::RefPtr<T>, nserror::nsresult> {
+        let mut ga = crate::GetterAddrefs::<T>::new();
+        let rv = unsafe { super::Gecko_GetServiceByModuleID(%(id)s, &T::IID, ga.void_ptr()) };
+        if rv.failed() {
+            return Err(rv);
+        }
+        ga.refptr().ok_or(nserror::NS_ERROR_NO_INTERFACE)
+    }
+"""
+            % substs
+        )
+
+        if not self.singleton:
+            res += (
+                """
+    /// Create a new instance of this component.
+    pub fn create<T: crate::XpCom>() -> Result<crate::RefPtr<T>, nserror::nsresult> {
+        let mut ga = crate::GetterAddrefs::<T>::new();
+        let rv = unsafe { super::Gecko_CreateInstanceByModuleID(%(id)s, &T::IID, ga.void_ptr()) };
+        if rv.failed() {
+            return Err(rv);
+        }
+        ga.refptr().ok_or(nserror::NS_ERROR_NO_INTERFACE)
+    }
+"""
+                % substs
+            )
+
+        res += """\
+}
+"""
+
+        return res
+
+
+# Returns a quoted string literal representing the given raw string, with
+# certain special characters replaced so that it can be used in a C++-style
+# (/* ... */) comment.
+def pretty_string(string):
+    return json.dumps(string).replace("*/", r"*\/").replace("/*", r"/\*")
+
+
+# Represents a static contract ID entry, corresponding to a C++ ContractEntry
+# struct, mapping a contract ID to a static module entry.
+class ContractEntry(object):
+    def __init__(self, contract, module):
+        self.contract = contract
+        self.module = module
+
+    def to_cxx(self):
+        return """
+        {{
+          {contract},
+          {module_id},
+        }}""".format(
+            contract=strings.entry_to_cxx(self.contract),
+            module_id=lower_module_id(self.module),
+        )
+
+
+# Represents a static ProtocolHandler entry, corresponding to a C++
+# ProtocolEntry struct, mapping a scheme to a static module entry and metadata.
+class ProtocolHandler(object):
+    def __init__(self, config, module):
+        def error(str_):
+            raise Exception(
+                "Error defining protocol handler %s (%s): %s"
+                % (str(module.cid), ", ".join(map(repr, module.contract_ids)), str_)
+            )
+
+        self.module = module
+        self.scheme = config.get("scheme", None)
+        if self.scheme is None:
+            error("No scheme defined for protocol component")
+        self.flags = config.get("flags", None)
+        if self.flags is None:
+            error("No flags defined for protocol component")
+        self.default_port = config.get("default_port", -1)
+        self.has_dynamic_flags = config.get("has_dynamic_flags", False)
+
+    def to_cxx(self):
+        return """
+        {{
+          .mScheme = {scheme},
+          .mProtocolFlags = {flags},
+          .mDefaultPort = {default_port},
+          .mModuleID = {module_id},
+          .mHasDynamicFlags = {has_dynamic_flags},
+        }}
+        """.format(
+            scheme=strings.entry_to_cxx(self.scheme),
+            module_id=lower_module_id(self.module),
+            flags=" | ".join("nsIProtocolHandler::%s" % flag for flag in self.flags),
+            default_port=self.default_port,
+            has_dynamic_flags="true" if self.has_dynamic_flags else "false",
+        )
+
+
+# Generates the C++ code for the StaticCategoryEntry and StaticCategory
+# structs for all category entries declared in XPCOM manifests.
+def gen_categories(substs, categories):
+    cats = []
+    ents = []
+
+    count = 0
+    for category, entries in sorted(categories.items()):
+
+        def k(entry):
+            return tuple(entry[0]["name"]) + entry[1:]
+
+        entries.sort(key=k)
+
+        cats.append(
+            "  { %s,\n"
+            "    %d, %d },\n" % (strings.entry_to_cxx(category), count, len(entries))
+        )
+        count += len(entries)
+
+        ents.append("  /* %s */\n" % pretty_string(category))
+        for entry, value, processes in entries:
+            name = entry["name"]
+            backgroundtasks = entry.get(
+                "backgroundtasks", BackgroundTasksSelector.NO_TASKS
+            )
+
+            ents.append(
+                "  { %s,\n"
+                "    %s,\n"
+                "    %s,\n"
+                "    %s },\n"
+                % (
+                    strings.entry_to_cxx(name),
+                    strings.entry_to_cxx(value),
+                    lower_backgroundtasks(backgroundtasks),
+                    lower_processes(processes),
+                )
+            )
+        ents.append("\n")
+    ents.pop()
+
+    substs["category_count"] = len(cats)
+    substs["categories"] = "".join(cats)
+    substs["category_entries"] = "".join(ents)
+
+
+# Generates the C++ code for all Init and Unload functions declared in XPCOM
+# manifests. These form the bodies of the `CallInitFunc()` and `CallUnload`
+# functions in StaticComponents.cpp.
+def gen_module_funcs(substs, funcs):
+    inits = []
+    unloads = []
+
+    template = """\
+    case %d:
+      %s
+      break;
+"""
+
+    for i, (init, unload) in enumerate(funcs):
+        init_code = "%s();" % init if init else "/* empty */"
+        inits.append(template % (i, init_code))
+
+        if unload:
+            unloads.append(
+                """\
+  if (CalledInit(%d)) {
+    %s();
+  }
+"""
+                % (i, unload)
+            )
+
+    substs["init_funcs"] = "".join(inits)
+    substs["unload_funcs"] = "".join(unloads)
+    substs["init_count"] = len(funcs)
+
+
+def gen_interfaces(ifaces):
+    res = []
+    for iface in ifaces:
+        res.append("  nsXPTInterface::%s,\n" % iface)
+    return "".join(res)
+
+
+# Generates class pre-declarations for any types referenced in `Classes` array
+# entries which do not have corresponding `headers` entries to fully declare
+# their types.
+def gen_decls(types):
+    root_ns = Namespace()
+
+    for type_ in sorted(types):
+        parts = type_.split("::")
+
+        ns = root_ns
+        for part in parts[:-1]:
+            ns = ns.sub(part)
+        ns.classes.add(parts[-1])
+
+    return root_ns.to_cxx()
+
+
+# Generates the `switch` body for the `CreateInstanceImpl()` function, with a
+# `case` for each value in ModuleID to construct an instance of the
+# corresponding component.
+def gen_constructors(entries):
+    constructors = []
+    for entry in entries:
+        constructors.append(
+            """\
+    case {id}: {{
+{constructor}\
+    }}
+""".format(
+                id=lower_module_id(entry), constructor=entry.lower_constructor()
+            )
+        )
+
+    return "".join(constructors)
+
+
+# Generates the getter code for each named component entry in the
+# `mozilla::components::` namespace.
+def gen_getters(entries):
+    entries = list(entries)
+    entries.sort(key=lambda e: e.name)
+
+    return "".join(entry.lower_getters() for entry in entries if not entry.anonymous)
+
+
+# Generates the rust getter code for each named component entry in the
+# `xpcom::components::` module.
+def gen_getters_rust(entries):
+    entries = list(entries)
+    entries.sort(key=lambda e: e.name)
+
+    return "".join(
+        entry.lower_getters_rust() for entry in entries if not entry.anonymous
+    )
+
+
+def gen_includes(substs, all_headers):
+    headers = set()
+    absolute_headers = set()
+
+    for header in all_headers:
+        if header.startswith("/"):
+            absolute_headers.add(header)
+        else:
+            headers.add(header)
+
+    includes = ['#include "%s"' % header for header in sorted(headers)]
+    substs["includes"] = "\n".join(includes) + "\n"
+
+    relative_includes = [
+        '#include "../..%s"' % header for header in sorted(absolute_headers)
+    ]
+    substs["relative_includes"] = "\n".join(relative_includes) + "\n"
+
+
+def to_category_list(val):
+    # Entries can be bare strings (like `"m-browser"`), lists of bare strings,
+    # or dictionaries (like `{"name": "m-browser", "backgroundtasks":
+    # BackgroundTasksSelector.ALL_TASKS}`), somewhat recursively.
+
+    def ensure_dict(v):
+        # Turn `v` into `{"name": v}` if it's not already a dict.
+        if isinstance(v, dict):
+            return v
+        return {"name": v}
+
+    if isinstance(val, (list, tuple)):
+        return tuple(ensure_dict(v) for v in val)
+
+    if isinstance(val, dict):
+        # Explode `{"name": ["x", "y"], "backgroundtasks": ...}` into
+        # `[{"name": "x", "backgroundtasks": ...}, {"name": "y", "backgroundtasks": ...}]`.
+        names = val.pop("name")
+
+        vals = []
+        for entry in to_category_list(names):
+            d = dict(val)
+            d["name"] = entry["name"]
+            vals.append(d)
+
+        return tuple(vals)
+
+    return (ensure_dict(val),)
+
+
+def gen_substs(manifests):
+    module_funcs = []
+
+    headers = set()
+
+    modules = []
+    categories = defaultdict(list)
+
+    for manifest in manifests:
+        headers |= set(manifest.get("Headers", []))
+
+        init_idx = None
+        init = manifest.get("InitFunc")
+        unload = manifest.get("UnloadFunc")
+        if init or unload:
+            init_idx = len(module_funcs)
+            module_funcs.append((init, unload))
+
+        for clas in manifest["Classes"]:
+            modules.append(ModuleEntry(clas, init_idx))
+
+        for category, entries in manifest.get("Categories", {}).items():
+            for key, entry in entries.items():
+                if isinstance(entry, tuple):
+                    value, process = entry
+                else:
+                    value, process = entry, 0
+                categories[category].append(({"name": key}, value, process))
+
+    cids = set()
+    contracts = []
+    contract_map = {}
+    js_services = {}
+    protocol_handlers = {}
+
+    jsms = set()
+    esModules = set()
+
+    types = set()
+
+    for mod in modules:
+        headers |= set(mod.headers)
+
+        for contract_id in mod.contract_ids:
+            if contract_id in contract_map:
+                raise Exception("Duplicate contract ID: %s" % contract_id)
+
+            entry = ContractEntry(contract_id, mod)
+            contracts.append(entry)
+            contract_map[contract_id] = entry
+
+        for category, entries in mod.categories.items():
+            for entry in to_category_list(entries):
+                categories[category].append((entry, mod.contract_id, mod.processes))
+
+        if mod.type and not mod.headers:
+            types.add(mod.type)
+
+        if mod.jsm:
+            jsms.add(mod.jsm)
+
+        if mod.esModule:
+            esModules.add(mod.esModule)
+
+        if mod.js_name:
+            if mod.js_name in js_services:
+                raise Exception("Duplicate JS service name: %s" % mod.js_name)
+            js_services[mod.js_name] = mod
+
+        if mod.protocol_config:
+            handler = ProtocolHandler(mod.protocol_config, mod)
+            if handler.scheme in protocol_handlers:
+                raise Exception("Duplicate protocol handler: %s" % handler.scheme)
+            protocol_handlers[handler.scheme] = handler
+
+        if str(mod.cid) in cids:
+            raise Exception("Duplicate cid: %s" % str(mod.cid))
+        cids.add(str(mod.cid))
+
+    cid_phf = PerfectHash(modules, PHF_SIZE, key=lambda module: module.cid.bytes)
+
+    contract_phf = PerfectHash(contracts, PHF_SIZE, key=lambda entry: entry.contract)
+
+    js_services_phf = PerfectHash(
+        list(js_services.values()), PHF_SIZE, key=lambda entry: entry.js_name
+    )
+
+    protocol_handlers_phf = PerfectHash(
+        list(protocol_handlers.values()), TINY_PHF_SIZE, key=lambda entry: entry.scheme
+    )
+
+    js_services_json = {}
+    for entry in js_services.values():
+        for iface in entry.interfaces:
+            js_services_json[iface] = entry.js_name
+
+    substs = {}
+
+    gen_categories(substs, categories)
+
+    substs["module_ids"] = "".join("  %s,\n" % entry.name for entry in cid_phf.entries)
+
+    substs["module_count"] = len(modules)
+    substs["contract_count"] = len(contracts)
+    substs["protocol_handler_count"] = len(protocol_handlers)
+
+    substs["default_protocol_handler_idx"] = protocol_handlers_phf.get_index("default")
+
+    gen_module_funcs(substs, module_funcs)
+
+    gen_includes(substs, headers)
+
+    substs["component_jsms"] = (
+        "\n".join(" %s," % strings.entry_to_cxx(jsm) for jsm in sorted(jsms)) + "\n"
+    )
+    substs["component_esmodules"] = (
+        "\n".join(
+            " %s," % strings.entry_to_cxx(esModule) for esModule in sorted(esModules)
+        )
+        + "\n"
+    )
+
+    substs["interfaces"] = gen_interfaces(interfaces)
+
+    substs["decls"] = gen_decls(types)
+
+    substs["constructors"] = gen_constructors(cid_phf.entries)
+
+    substs["component_getters"] = gen_getters(cid_phf.entries)
+
+    substs["component_getters_rust"] = gen_getters_rust(cid_phf.entries)
+
+    substs["module_cid_table"] = cid_phf.cxx_codegen(
+        name="ModuleByCID",
+        entry_type="StaticModule",
+        entries_name="gStaticModules",
+        lower_entry=lambda entry: entry.to_cxx(),
+        return_type="const StaticModule*",
+        return_entry=(
+            "return entry.CID().Equals(aKey) && entry.Active()" " ? &entry : nullptr;"
+        ),
+        key_type="const nsID&",
+        key_bytes="reinterpret_cast<const char*>(&aKey)",
+        key_length="sizeof(nsID)",
+    )
+
+    substs["module_contract_id_table"] = contract_phf.cxx_codegen(
+        name="LookupContractID",
+        entry_type="ContractEntry",
+        entries_name="gContractEntries",
+        lower_entry=lambda entry: entry.to_cxx(),
+        return_type="const ContractEntry*",
+        return_entry="return entry.Matches(aKey) ? &entry : nullptr;",
+        key_type="const nsACString&",
+        key_bytes="aKey.BeginReading()",
+        key_length="aKey.Length()",
+    )
+
+    substs["js_services_table"] = js_services_phf.cxx_codegen(
+        name="LookupJSService",
+        entry_type="JSServiceEntry",
+        entries_name="gJSServices",
+        lower_entry=lambda entry: entry.lower_js_service(),
+        return_type="const JSServiceEntry*",
+        return_entry="return entry.Name() == aKey ? &entry : nullptr;",
+        key_type="const nsACString&",
+        key_bytes="aKey.BeginReading()",
+        key_length="aKey.Length()",
+    )
+
+    substs["protocol_handlers_table"] = protocol_handlers_phf.cxx_codegen(
+        name="LookupProtocolHandler",
+        entry_type="StaticProtocolHandler",
+        entries_name="gStaticProtocolHandlers",
+        lower_entry=lambda entry: entry.to_cxx(),
+        return_type="const StaticProtocolHandler*",
+        return_entry="return entry.Scheme() == aKey ? &entry : nullptr;",
+        key_type="const nsACString&",
+        key_bytes="aKey.BeginReading()",
+        key_length="aKey.Length()",
+    )
+
+    substs["js_services_json"] = json.dumps(js_services_json, sort_keys=True, indent=4)
+
+    # Do this only after everything else has been emitted so we're sure the
+    # string table is complete.
+    substs["strings"] = strings.to_cxx()
+    return substs
+
+
+# Returns true if the given build config substitution is defined and truthy.
+def defined(subst):
+    return bool(buildconfig.substs.get(subst))
+
+
+def read_manifest(filename):
+    glbl = {
+        "buildconfig": buildconfig,
+        "defined": defined,
+        "ProcessSelector": ProcessSelector,
+        "BackgroundTasksSelector": BackgroundTasksSelector,
+    }
+    code = compile(open(filename).read(), filename, "exec")
+    exec(code, glbl)
+    return glbl
+
+
+def main(fd, conf_file, template_file):
+    def open_output(filename):
+        return FileAvoidWrite(os.path.join(os.path.dirname(fd.name), filename))
+
+    conf = json.load(open(conf_file, "r"))
+
+    deps = set()
+
+    manifests = []
+    for filename in conf["manifests"]:
+        deps.add(filename)
+        manifest = read_manifest(filename)
+        manifests.append(manifest)
+        manifest.setdefault("Priority", 50)
+        manifest["__filename__"] = filename
+
+    manifests.sort(key=lambda man: (man["Priority"], man["__filename__"]))
+
+    substs = gen_substs(manifests)
+
+    def replacer(match):
+        return substs[match.group(1)]
+
+    with open_output("StaticComponents.cpp") as fh:
+        with open(template_file, "r") as tfh:
+            template = tfh.read()
+
+        fh.write(re.sub(r"//# @([a-zA-Z_]+)@\n", replacer, template))
+
+    with open_output("StaticComponentData.h") as fh:
+        fh.write(
+            """\
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef StaticComponentData_h
+#define StaticComponentData_h
+
+#include <stddef.h>
+
+namespace mozilla {
+namespace xpcom {
+
+static constexpr size_t kStaticModuleCount = %(module_count)d;
+
+static constexpr size_t kContractCount = %(contract_count)d;
+
+static constexpr size_t kStaticCategoryCount = %(category_count)d;
+
+static constexpr size_t kModuleInitCount = %(init_count)d;
+
+static constexpr size_t kStaticProtocolHandlerCount = %(protocol_handler_count)d;
+
+static constexpr size_t kDefaultProtocolHandlerIndex = %(default_protocol_handler_idx)d;
+
+}  // namespace xpcom
+}  // namespace mozilla
+
+#endif
+"""
+            % substs
+        )
+
+    with open_output("components.rs") as fh:
+        fh.write(
+            """\
+/// Unique IDs for each statically-registered module.
+#[repr(u16)]
+pub enum ModuleID {
+%(module_ids)s
+}
+
+%(component_getters_rust)s
+"""
+            % substs
+        )
+
+    fd.write(
+        """\
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_Components_h
+#define mozilla_Components_h
+
+#include "nsCOMPtr.h"
+
+struct nsID;
+
+#define NS_IMPL_COMPONENT_FACTORY(iface) \\
+  template <>                            \\
+  already_AddRefed<nsISupports> mozCreateComponent<iface>()
+
+template <typename T>
+already_AddRefed<nsISupports> mozCreateComponent();
+
+namespace mozilla {
+namespace xpcom {
+
+enum class ModuleID : uint16_t {
+%(module_ids)s
+};
+
+// May be added as a friend function to allow constructing services via
+// private constructors and init methods.
+nsresult CreateInstanceImpl(ModuleID aID, const nsIID& aIID, void** aResult);
+
+class MOZ_STACK_CLASS StaticModuleHelper : public nsCOMPtr_helper {
+ public:
+  StaticModuleHelper(ModuleID aId, nsresult* aErrorPtr)
+      : mId(aId), mErrorPtr(aErrorPtr) {}
+
+ protected:
+  nsresult SetResult(nsresult aRv) const {
+    if (mErrorPtr) {
+      *mErrorPtr = aRv;
+    }
+    return aRv;
+  }
+
+  ModuleID mId;
+  nsresult* mErrorPtr;
+};
+
+class MOZ_STACK_CLASS GetServiceHelper final : public StaticModuleHelper {
+ public:
+  using StaticModuleHelper::StaticModuleHelper;
+
+  nsresult NS_FASTCALL operator()(const nsIID& aIID,
+                                  void** aResult) const override;
+};
+
+class MOZ_STACK_CLASS CreateInstanceHelper final : public StaticModuleHelper {
+ public:
+  using StaticModuleHelper::StaticModuleHelper;
+
+  nsresult NS_FASTCALL operator()(const nsIID& aIID,
+                                  void** aResult) const override;
+};
+
+class Components final {
+ public:
+  static const nsID& GetCID(ModuleID aID);
+};
+
+}  // namespace xpcom
+
+namespace components {
+%(component_getters)s
+}  // namespace components
+
+}  // namespace mozilla
+
+#endif
+"""
+        % substs
+    )
+
+    with open_output("services.json") as fh:
+        fh.write(substs["js_services_json"])
+
+    return deps