init: remove Parser singleton and related cleanup

* Remove the Parser singleton (Hooray!)
* Rename parser.* to tokenizer.* as this is actually a tokenizer
* Rename init_parser.* to parser.* as this is a generic parser
* Move contents of init_parser_test.cpp to service_test.cpp as this
  actually is a test of the parsing in MakeExecOneshotService() and
  nothing related to (init_)parser.cpp

Test: boot bullhead
Test: bool sailfish
Test: init unit tests
Change-Id: I4fe39e6483f58ebd3ce5ee715a45dbba0acf5d91
diff --git a/init/Android.bp b/init/Android.bp
index 8294598..6e95baa 100644
--- a/init/Android.bp
+++ b/init/Android.bp
@@ -67,10 +67,10 @@
         "devices.cpp",
         "firmware_handler.cpp",
         "import_parser.cpp",
-        "init_parser.cpp",
         "log.cpp",
         "parser.cpp",
         "service.cpp",
+        "tokenizer.cpp",
         "uevent_listener.cpp",
         "ueventd_parser.cpp",
         "util.cpp",
@@ -153,7 +153,6 @@
     defaults: ["init_defaults"],
     srcs: [
         "devices_test.cpp",
-        "init_parser_test.cpp",
         "init_test.cpp",
         "property_service_test.cpp",
         "service_test.cpp",
diff --git a/init/action.h b/init/action.h
index ad15f3f..50cae71 100644
--- a/init/action.h
+++ b/init/action.h
@@ -24,8 +24,8 @@
 #include <vector>
 
 #include "builtins.h"
-#include "init_parser.h"
 #include "keyword_map.h"
+#include "parser.h"
 
 namespace android {
 namespace init {
diff --git a/init/builtins.cpp b/init/builtins.cpp
index dfd7b73..dec6f40 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -57,7 +57,7 @@
 #include "action.h"
 #include "bootchart.h"
 #include "init.h"
-#include "init_parser.h"
+#include "parser.h"
 #include "property_service.h"
 #include "reboot.h"
 #include "service.h"
@@ -388,21 +388,15 @@
  * start_index: index of the first path in the args list
  */
 static void import_late(const std::vector<std::string>& args, size_t start_index, size_t end_index) {
-    Parser& parser = Parser::GetInstance();
+    auto& action_manager = ActionManager::GetInstance();
+    auto& service_manager = ServiceManager::GetInstance();
+    Parser parser = CreateParser(action_manager, service_manager);
     if (end_index <= start_index) {
         // Fallbacks for partitions on which early mount isn't enabled.
-        if (!parser.is_system_etc_init_loaded()) {
-            parser.ParseConfig("/system/etc/init");
-            parser.set_is_system_etc_init_loaded(true);
+        for (const auto& path : late_import_paths) {
+            parser.ParseConfig(path);
         }
-        if (!parser.is_vendor_etc_init_loaded()) {
-            parser.ParseConfig("/vendor/etc/init");
-            parser.set_is_vendor_etc_init_loaded(true);
-        }
-        if (!parser.is_odm_etc_init_loaded()) {
-            parser.ParseConfig("/odm/etc/init");
-            parser.set_is_odm_etc_init_loaded(true);
-        }
+        late_import_paths.clear();
     } else {
         for (size_t i = start_index; i < end_index; ++i) {
             parser.ParseConfig(args[i]);
diff --git a/init/import_parser.h b/init/import_parser.h
index b774c57..0d04e0e 100644
--- a/init/import_parser.h
+++ b/init/import_parser.h
@@ -17,11 +17,11 @@
 #ifndef _INIT_IMPORT_PARSER_H
 #define _INIT_IMPORT_PARSER_H
 
-#include "init_parser.h"
-
 #include <string>
 #include <vector>
 
+#include "parser.h"
+
 namespace android {
 namespace init {
 
diff --git a/init/init.cpp b/init/init.cpp
index 7fbc3b7..f063c3f 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -55,16 +55,13 @@
 #include <memory>
 #include <vector>
 
-#include "action.h"
 #include "bootchart.h"
 #include "import_parser.h"
 #include "init_first_stage.h"
-#include "init_parser.h"
 #include "keychords.h"
 #include "log.h"
 #include "property_service.h"
 #include "reboot.h"
-#include "service.h"
 #include "signal_handler.h"
 #include "ueventd.h"
 #include "util.h"
@@ -98,11 +95,43 @@
 static std::string wait_prop_value;
 static bool shutting_down;
 
+std::vector<std::string> late_import_paths;
+
 void DumpState() {
     ServiceManager::GetInstance().DumpState();
     ActionManager::GetInstance().DumpState();
 }
 
+Parser CreateParser(ActionManager& action_manager, ServiceManager& service_manager) {
+    Parser parser;
+
+    parser.AddSectionParser("service", std::make_unique<ServiceParser>(&service_manager));
+    parser.AddSectionParser("on", std::make_unique<ActionParser>(&action_manager));
+    parser.AddSectionParser("import", std::make_unique<ImportParser>(&parser));
+
+    return parser;
+}
+
+static void LoadBootScripts(ActionManager& action_manager, ServiceManager& service_manager) {
+    Parser parser = CreateParser(action_manager, service_manager);
+
+    std::string bootscript = GetProperty("ro.boot.init_rc", "");
+    if (bootscript.empty()) {
+        parser.ParseConfig("/init.rc");
+        if (!parser.ParseConfig("/system/etc/init")) {
+            late_import_paths.emplace_back("/system/etc/init");
+        }
+        if (!parser.ParseConfig("/vendor/etc/init")) {
+            late_import_paths.emplace_back("/vendor/etc/init");
+        }
+        if (!parser.ParseConfig("/odm/etc/init")) {
+            late_import_paths.emplace_back("/odm/etc/init");
+        }
+    } else {
+        parser.ParseConfig(bootscript);
+    }
+}
+
 void register_epoll_handler(int fd, void (*fn)()) {
     epoll_event ev;
     ev.events = EPOLLIN;
@@ -1102,25 +1131,8 @@
 
     ActionManager& am = ActionManager::GetInstance();
     ServiceManager& sm = ServiceManager::GetInstance();
-    Parser& parser = Parser::GetInstance();
 
-    parser.AddSectionParser("service", std::make_unique<ServiceParser>(&sm));
-    parser.AddSectionParser("on", std::make_unique<ActionParser>(&am));
-    parser.AddSectionParser("import", std::make_unique<ImportParser>(&parser));
-    std::string bootscript = GetProperty("ro.boot.init_rc", "");
-    if (bootscript.empty()) {
-        parser.ParseConfig("/init.rc");
-        parser.set_is_system_etc_init_loaded(
-                parser.ParseConfig("/system/etc/init"));
-        parser.set_is_vendor_etc_init_loaded(
-                parser.ParseConfig("/vendor/etc/init"));
-        parser.set_is_odm_etc_init_loaded(parser.ParseConfig("/odm/etc/init"));
-    } else {
-        parser.ParseConfig(bootscript);
-        parser.set_is_system_etc_init_loaded(true);
-        parser.set_is_vendor_etc_init_loaded(true);
-        parser.set_is_odm_etc_init_loaded(true);
-    }
+    LoadBootScripts(am, sm);
 
     // Turning this on and letting the INFO logging be discarded adds 0.2s to
     // Nexus 9 boot time, so it's disabled by default.
diff --git a/init/init.h b/init/init.h
index aaab523..0a77bd2 100644
--- a/init/init.h
+++ b/init/init.h
@@ -21,6 +21,10 @@
 
 #include <selinux/label.h>
 
+#include "action.h"
+#include "parser.h"
+#include "service.h"
+
 namespace android {
 namespace init {
 
@@ -32,6 +36,10 @@
 extern struct selabel_handle *sehandle;
 extern struct selabel_handle *sehandle_prop;
 
+extern std::vector<std::string> late_import_paths;
+
+Parser CreateParser(ActionManager& action_manager, ServiceManager& service_manager);
+
 void handle_control_message(const std::string& msg, const std::string& arg);
 
 void property_changed(const std::string& name, const std::string& value);
diff --git a/init/init_parser.cpp b/init/init_parser.cpp
deleted file mode 100644
index 9f7089b..0000000
--- a/init/init_parser.cpp
+++ /dev/null
@@ -1,168 +0,0 @@
-/*
- * Copyright (C) 2010 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "init_parser.h"
-
-#include <dirent.h>
-
-#include <android-base/chrono_utils.h>
-#include <android-base/logging.h>
-#include <android-base/stringprintf.h>
-#include <android-base/strings.h>
-
-#include "parser.h"
-#include "util.h"
-
-namespace android {
-namespace init {
-
-Parser::Parser() {
-}
-
-Parser& Parser::GetInstance() {
-    static Parser instance;
-    return instance;
-}
-
-void Parser::AddSectionParser(const std::string& name,
-                              std::unique_ptr<SectionParser> parser) {
-    section_parsers_[name] = std::move(parser);
-}
-
-void Parser::AddSingleLineParser(const std::string& prefix, LineCallback callback) {
-    line_callbacks_.emplace_back(prefix, callback);
-}
-
-void Parser::ParseData(const std::string& filename, const std::string& data) {
-    //TODO: Use a parser with const input and remove this copy
-    std::vector<char> data_copy(data.begin(), data.end());
-    data_copy.push_back('\0');
-
-    parse_state state;
-    state.line = 0;
-    state.ptr = &data_copy[0];
-    state.nexttoken = 0;
-
-    SectionParser* section_parser = nullptr;
-    std::vector<std::string> args;
-
-    for (;;) {
-        switch (next_token(&state)) {
-        case T_EOF:
-            if (section_parser) {
-                section_parser->EndSection();
-            }
-            return;
-        case T_NEWLINE:
-            state.line++;
-            if (args.empty()) {
-                break;
-            }
-            // If we have a line matching a prefix we recognize, call its callback and unset any
-            // current section parsers.  This is meant for /sys/ and /dev/ line entries for uevent.
-            for (const auto& [prefix, callback] : line_callbacks_) {
-                if (android::base::StartsWith(args[0], prefix.c_str())) {
-                    if (section_parser) section_parser->EndSection();
-
-                    std::string ret_err;
-                    if (!callback(std::move(args), &ret_err)) {
-                        LOG(ERROR) << filename << ": " << state.line << ": " << ret_err;
-                    }
-                    section_parser = nullptr;
-                    break;
-                }
-            }
-            if (section_parsers_.count(args[0])) {
-                if (section_parser) {
-                    section_parser->EndSection();
-                }
-                section_parser = section_parsers_[args[0]].get();
-                std::string ret_err;
-                if (!section_parser->ParseSection(std::move(args), filename, state.line, &ret_err)) {
-                    LOG(ERROR) << filename << ": " << state.line << ": " << ret_err;
-                    section_parser = nullptr;
-                }
-            } else if (section_parser) {
-                std::string ret_err;
-                if (!section_parser->ParseLineSection(std::move(args), state.line, &ret_err)) {
-                    LOG(ERROR) << filename << ": " << state.line << ": " << ret_err;
-                }
-            }
-            args.clear();
-            break;
-        case T_TEXT:
-            args.emplace_back(state.text);
-            break;
-        }
-    }
-}
-
-bool Parser::ParseConfigFile(const std::string& path) {
-    LOG(INFO) << "Parsing file " << path << "...";
-    android::base::Timer t;
-    std::string data;
-    std::string err;
-    if (!ReadFile(path, &data, &err)) {
-        LOG(ERROR) << err;
-        return false;
-    }
-
-    data.push_back('\n'); // TODO: fix parse_config.
-    ParseData(path, data);
-    for (const auto& [section_name, section_parser] : section_parsers_) {
-        section_parser->EndFile();
-    }
-
-    LOG(VERBOSE) << "(Parsing " << path << " took " << t << ".)";
-    return true;
-}
-
-bool Parser::ParseConfigDir(const std::string& path) {
-    LOG(INFO) << "Parsing directory " << path << "...";
-    std::unique_ptr<DIR, int(*)(DIR*)> config_dir(opendir(path.c_str()), closedir);
-    if (!config_dir) {
-        PLOG(ERROR) << "Could not import directory '" << path << "'";
-        return false;
-    }
-    dirent* current_file;
-    std::vector<std::string> files;
-    while ((current_file = readdir(config_dir.get()))) {
-        // Ignore directories and only process regular files.
-        if (current_file->d_type == DT_REG) {
-            std::string current_path =
-                android::base::StringPrintf("%s/%s", path.c_str(), current_file->d_name);
-            files.emplace_back(current_path);
-        }
-    }
-    // Sort first so we load files in a consistent order (bug 31996208)
-    std::sort(files.begin(), files.end());
-    for (const auto& file : files) {
-        if (!ParseConfigFile(file)) {
-            LOG(ERROR) << "could not import file '" << file << "'";
-        }
-    }
-    return true;
-}
-
-bool Parser::ParseConfig(const std::string& path) {
-    if (is_dir(path.c_str())) {
-        return ParseConfigDir(path);
-    }
-    return ParseConfigFile(path);
-}
-
-}  // namespace init
-}  // namespace android
diff --git a/init/init_parser.h b/init/init_parser.h
deleted file mode 100644
index c07a699..0000000
--- a/init/init_parser.h
+++ /dev/null
@@ -1,102 +0,0 @@
-/*
- * Copyright (C) 2010 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#ifndef _INIT_INIT_PARSER_H_
-#define _INIT_INIT_PARSER_H_
-
-#include <map>
-#include <memory>
-#include <string>
-#include <vector>
-
-//  SectionParser is an interface that can parse a given 'section' in init.
-//
-//  You can implement up to 4 functions below, with ParseSection() being mandatory.
-//  The first two function return bool with false indicating a failure and has a std::string* err
-//  parameter into which an error string can be written.  It will be reported along with the
-//  filename and line number of where the error occurred.
-//
-//  1) bool ParseSection(std::vector<std::string>&& args, const std::string& filename,
-//                       int line, std::string* err)
-//    This function is called when a section is first encountered.
-//
-//  2) bool ParseLineSection(std::vector<std::string>&& args, int line, std::string* err)
-//    This function is called on each subsequent line until the next section is encountered.
-//
-//  3) bool EndSection()
-//    This function is called either when a new section is found or at the end of the file.
-//    It indicates that parsing of the current section is complete and any relevant objects should
-//    be committed.
-//
-//  4) bool EndFile()
-//    This function is called at the end of the file.
-//    It indicates that the parsing has completed and any relevant objects should be committed.
-
-namespace android {
-namespace init {
-
-class SectionParser {
-  public:
-    virtual ~SectionParser() {}
-    virtual bool ParseSection(std::vector<std::string>&& args, const std::string& filename,
-                              int line, std::string* err) = 0;
-    virtual bool ParseLineSection(std::vector<std::string>&&, int, std::string*) { return true; };
-    virtual void EndSection(){};
-    virtual void EndFile(){};
-};
-
-class Parser {
-  public:
-    //  LineCallback is the type for callbacks that can parse a line starting with a given prefix.
-    //
-    //  They take the form of bool Callback(std::vector<std::string>&& args, std::string* err)
-    //
-    //  Similar to ParseSection() and ParseLineSection(), this function returns bool with false
-    //  indicating a failure and has an std::string* err parameter into which an error string can
-    //  be written.
-    using LineCallback = std::function<bool(std::vector<std::string>&&, std::string*)>;
-
-    // TODO: init is the only user of this as a singleton; remove it.
-    static Parser& GetInstance();
-
-    Parser();
-
-    bool ParseConfig(const std::string& path);
-    void AddSectionParser(const std::string& name, std::unique_ptr<SectionParser> parser);
-    void AddSingleLineParser(const std::string& prefix, LineCallback callback);
-    void set_is_system_etc_init_loaded(bool loaded) { is_system_etc_init_loaded_ = loaded; }
-    void set_is_vendor_etc_init_loaded(bool loaded) { is_vendor_etc_init_loaded_ = loaded; }
-    void set_is_odm_etc_init_loaded(bool loaded) { is_odm_etc_init_loaded_ = loaded; }
-    bool is_system_etc_init_loaded() { return is_system_etc_init_loaded_; }
-    bool is_vendor_etc_init_loaded() { return is_vendor_etc_init_loaded_; }
-    bool is_odm_etc_init_loaded() { return is_odm_etc_init_loaded_; }
-
-  private:
-    void ParseData(const std::string& filename, const std::string& data);
-    bool ParseConfigFile(const std::string& path);
-    bool ParseConfigDir(const std::string& path);
-
-    std::map<std::string, std::unique_ptr<SectionParser>> section_parsers_;
-    std::vector<std::pair<std::string, LineCallback>> line_callbacks_;
-    bool is_system_etc_init_loaded_ = false;
-    bool is_vendor_etc_init_loaded_ = false;
-    bool is_odm_etc_init_loaded_ = false;
-};
-
-}  // namespace init
-}  // namespace android
-
-#endif
diff --git a/init/init_parser_test.cpp b/init/init_parser_test.cpp
deleted file mode 100644
index 95f269a..0000000
--- a/init/init_parser_test.cpp
+++ /dev/null
@@ -1,150 +0,0 @@
-/*
- * Copyright (C) 2015 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "init_parser.h"
-
-#include <string>
-#include <vector>
-
-#include <gtest/gtest.h>
-
-#include "init.h"
-#include "service.h"
-#include "util.h"
-
-namespace android {
-namespace init {
-
-TEST(init_parser, make_exec_oneshot_service_invalid_syntax) {
-    ServiceManager& sm = ServiceManager::GetInstance();
-    std::vector<std::string> args;
-    // Nothing.
-    ASSERT_EQ(nullptr, sm.MakeExecOneshotService(args));
-
-    // No arguments to 'exec'.
-    args.push_back("exec");
-    ASSERT_EQ(nullptr, sm.MakeExecOneshotService(args));
-
-    // No command in "exec --".
-    args.push_back("--");
-    ASSERT_EQ(nullptr, sm.MakeExecOneshotService(args));
-}
-
-TEST(init_parser, make_exec_oneshot_service_too_many_supplementary_gids) {
-    ServiceManager& sm = ServiceManager::GetInstance();
-    std::vector<std::string> args;
-    args.push_back("exec");
-    args.push_back("seclabel");
-    args.push_back("root"); // uid.
-    args.push_back("root"); // gid.
-    for (int i = 0; i < NR_SVC_SUPP_GIDS; ++i) {
-        args.push_back("root"); // Supplementary gid.
-    }
-    args.push_back("--");
-    args.push_back("/system/bin/id");
-    ASSERT_EQ(nullptr, sm.MakeExecOneshotService(args));
-}
-
-static void Test_make_exec_oneshot_service(bool dash_dash, bool seclabel, bool uid,
-                                           bool gid, bool supplementary_gids) {
-    ServiceManager& sm = ServiceManager::GetInstance();
-    std::vector<std::string> args;
-    args.push_back("exec");
-    if (seclabel) {
-        args.push_back("u:r:su:s0"); // seclabel
-        if (uid) {
-            args.push_back("log");      // uid
-            if (gid) {
-                args.push_back("shell");     // gid
-                if (supplementary_gids) {
-                    args.push_back("system");    // supplementary gid 0
-                    args.push_back("adb");       // supplementary gid 1
-                }
-            }
-        }
-    }
-    if (dash_dash) {
-        args.push_back("--");
-    }
-    args.push_back("/system/bin/toybox");
-    args.push_back("id");
-    Service* svc = sm.MakeExecOneshotService(args);
-    ASSERT_NE(nullptr, svc);
-
-    if (seclabel) {
-        ASSERT_EQ("u:r:su:s0", svc->seclabel());
-    } else {
-        ASSERT_EQ("", svc->seclabel());
-    }
-    if (uid) {
-        uid_t decoded_uid;
-        std::string err;
-        ASSERT_TRUE(DecodeUid("log", &decoded_uid, &err));
-        ASSERT_EQ(decoded_uid, svc->uid());
-    } else {
-        ASSERT_EQ(0U, svc->uid());
-    }
-    if (gid) {
-        uid_t decoded_uid;
-        std::string err;
-        ASSERT_TRUE(DecodeUid("shell", &decoded_uid, &err));
-        ASSERT_EQ(decoded_uid, svc->gid());
-    } else {
-        ASSERT_EQ(0U, svc->gid());
-    }
-    if (supplementary_gids) {
-        ASSERT_EQ(2U, svc->supp_gids().size());
-        uid_t decoded_uid;
-        std::string err;
-        ASSERT_TRUE(DecodeUid("system", &decoded_uid, &err));
-        ASSERT_EQ(decoded_uid, svc->supp_gids()[0]);
-        ASSERT_TRUE(DecodeUid("adb", &decoded_uid, &err));
-        ASSERT_EQ(decoded_uid, svc->supp_gids()[1]);
-    } else {
-        ASSERT_EQ(0U, svc->supp_gids().size());
-    }
-
-    ASSERT_EQ(static_cast<std::size_t>(2), svc->args().size());
-    ASSERT_EQ("/system/bin/toybox", svc->args()[0]);
-    ASSERT_EQ("id", svc->args()[1]);
-}
-
-TEST(init_parser, make_exec_oneshot_service_with_everything) {
-    Test_make_exec_oneshot_service(true, true, true, true, true);
-}
-
-TEST(init_parser, make_exec_oneshot_service_with_seclabel_uid_gid) {
-    Test_make_exec_oneshot_service(true, true, true, true, false);
-}
-
-TEST(init_parser, make_exec_oneshot_service_with_seclabel_uid) {
-    Test_make_exec_oneshot_service(true, true, true, false, false);
-}
-
-TEST(init_parser, make_exec_oneshot_service_with_seclabel) {
-    Test_make_exec_oneshot_service(true, true, false, false, false);
-}
-
-TEST(init_parser, make_exec_oneshot_service_with_just_command) {
-    Test_make_exec_oneshot_service(true, false, false, false, false);
-}
-
-TEST(init_parser, make_exec_oneshot_service_with_just_command_no_dash) {
-    Test_make_exec_oneshot_service(false, false, false, false, false);
-}
-
-}  // namespace init
-}  // namespace android
diff --git a/init/init_test.cpp b/init/init_test.cpp
index 0a4071b..2062290 100644
--- a/init/init_test.cpp
+++ b/init/init_test.cpp
@@ -23,8 +23,8 @@
 #include "action.h"
 #include "builtins.h"
 #include "import_parser.h"
-#include "init_parser.h"
 #include "keyword_map.h"
+#include "parser.h"
 #include "util.h"
 
 namespace android {
diff --git a/init/parser.cpp b/init/parser.cpp
index c0fa6d9..c6f4f45 100644
--- a/init/parser.cpp
+++ b/init/parser.cpp
@@ -1,123 +1,156 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 #include "parser.h"
 
+#include <dirent.h>
+
+#include <android-base/chrono_utils.h>
+#include <android-base/logging.h>
+#include <android-base/stringprintf.h>
+#include <android-base/strings.h>
+
+#include "tokenizer.h"
+#include "util.h"
+
 namespace android {
 namespace init {
 
-int next_token(struct parse_state *state)
-{
-    char *x = state->ptr;
-    char *s;
+Parser::Parser() {}
 
-    if (state->nexttoken) {
-        int t = state->nexttoken;
-        state->nexttoken = 0;
-        return t;
-    }
+void Parser::AddSectionParser(const std::string& name, std::unique_ptr<SectionParser> parser) {
+    section_parsers_[name] = std::move(parser);
+}
+
+void Parser::AddSingleLineParser(const std::string& prefix, LineCallback callback) {
+    line_callbacks_.emplace_back(prefix, callback);
+}
+
+void Parser::ParseData(const std::string& filename, const std::string& data) {
+    // TODO: Use a parser with const input and remove this copy
+    std::vector<char> data_copy(data.begin(), data.end());
+    data_copy.push_back('\0');
+
+    parse_state state;
+    state.line = 0;
+    state.ptr = &data_copy[0];
+    state.nexttoken = 0;
+
+    SectionParser* section_parser = nullptr;
+    std::vector<std::string> args;
 
     for (;;) {
-        switch (*x) {
-        case 0:
-            state->ptr = x;
-            return T_EOF;
-        case '\n':
-            x++;
-            state->ptr = x;
-            return T_NEWLINE;
-        case ' ':
-        case '\t':
-        case '\r':
-            x++;
-            continue;
-        case '#':
-            while (*x && (*x != '\n')) x++;
-            if (*x == '\n') {
-                state->ptr = x+1;
-                return T_NEWLINE;
-            } else {
-                state->ptr = x;
-                return T_EOF;
-            }
-        default:
-            goto text;
+        switch (next_token(&state)) {
+            case T_EOF:
+                if (section_parser) section_parser->EndSection();
+                return;
+            case T_NEWLINE:
+                state.line++;
+                if (args.empty()) break;
+                // If we have a line matching a prefix we recognize, call its callback and unset any
+                // current section parsers.  This is meant for /sys/ and /dev/ line entries for
+                // uevent.
+                for (const auto& [prefix, callback] : line_callbacks_) {
+                    if (android::base::StartsWith(args[0], prefix.c_str())) {
+                        if (section_parser) section_parser->EndSection();
+
+                        std::string ret_err;
+                        if (!callback(std::move(args), &ret_err)) {
+                            LOG(ERROR) << filename << ": " << state.line << ": " << ret_err;
+                        }
+                        section_parser = nullptr;
+                        break;
+                    }
+                }
+                if (section_parsers_.count(args[0])) {
+                    if (section_parser) section_parser->EndSection();
+                    section_parser = section_parsers_[args[0]].get();
+                    std::string ret_err;
+                    if (!section_parser->ParseSection(std::move(args), filename, state.line,
+                                                      &ret_err)) {
+                        LOG(ERROR) << filename << ": " << state.line << ": " << ret_err;
+                        section_parser = nullptr;
+                    }
+                } else if (section_parser) {
+                    std::string ret_err;
+                    if (!section_parser->ParseLineSection(std::move(args), state.line, &ret_err)) {
+                        LOG(ERROR) << filename << ": " << state.line << ": " << ret_err;
+                    }
+                }
+                args.clear();
+                break;
+            case T_TEXT:
+                args.emplace_back(state.text);
+                break;
         }
     }
+}
+
+bool Parser::ParseConfigFile(const std::string& path) {
+    LOG(INFO) << "Parsing file " << path << "...";
+    android::base::Timer t;
+    std::string data;
+    std::string err;
+    if (!ReadFile(path, &data, &err)) {
+        LOG(ERROR) << err;
+        return false;
+    }
 
-textdone:
-    state->ptr = x;
-    *s = 0;
-    return T_TEXT;
-text:
-    state->text = s = x;
-textresume:
-    for (;;) {
-        switch (*x) {
-        case 0:
-            goto textdone;
-        case ' ':
-        case '\t':
-        case '\r':
-            x++;
-            goto textdone;
-        case '\n':
-            state->nexttoken = T_NEWLINE;
-            x++;
-            goto textdone;
-        case '"':
-            x++;
-            for (;;) {
-                switch (*x) {
-                case 0:
-                        /* unterminated quoted thing */
-                    state->ptr = x;
-                    return T_EOF;
-                case '"':
-                    x++;
-                    goto textresume;
-                default:
-                    *s++ = *x++;
-                }
-            }
-            break;
-        case '\\':
-            x++;
-            switch (*x) {
-            case 0:
-                goto textdone;
-            case 'n':
-                *s++ = '\n';
-                break;
-            case 'r':
-                *s++ = '\r';
-                break;
-            case 't':
-                *s++ = '\t';
-                break;
-            case '\\':
-                *s++ = '\\';
-                break;
-            case '\r':
-                    /* \ <cr> <lf> -> line continuation */
-                if (x[1] != '\n') {
-                    x++;
-                    continue;
-                }
-            case '\n':
-                    /* \ <lf> -> line continuation */
-                state->line++;
-                x++;
-                    /* eat any extra whitespace */
-                while((*x == ' ') || (*x == '\t')) x++;
-                continue;
-            default:
-                    /* unknown escape -- just copy */
-                *s++ = *x++;
-            }
-            continue;
-        default:
-            *s++ = *x++;
+    data.push_back('\n');  // TODO: fix parse_config.
+    ParseData(path, data);
+    for (const auto& [section_name, section_parser] : section_parsers_) {
+        section_parser->EndFile();
+    }
+
+    LOG(VERBOSE) << "(Parsing " << path << " took " << t << ".)";
+    return true;
+}
+
+bool Parser::ParseConfigDir(const std::string& path) {
+    LOG(INFO) << "Parsing directory " << path << "...";
+    std::unique_ptr<DIR, decltype(&closedir)> config_dir(opendir(path.c_str()), closedir);
+    if (!config_dir) {
+        PLOG(ERROR) << "Could not import directory '" << path << "'";
+        return false;
+    }
+    dirent* current_file;
+    std::vector<std::string> files;
+    while ((current_file = readdir(config_dir.get()))) {
+        // Ignore directories and only process regular files.
+        if (current_file->d_type == DT_REG) {
+            std::string current_path =
+                android::base::StringPrintf("%s/%s", path.c_str(), current_file->d_name);
+            files.emplace_back(current_path);
         }
     }
-    return T_EOF;
+    // Sort first so we load files in a consistent order (bug 31996208)
+    std::sort(files.begin(), files.end());
+    for (const auto& file : files) {
+        if (!ParseConfigFile(file)) {
+            LOG(ERROR) << "could not import file '" << file << "'";
+        }
+    }
+    return true;
+}
+
+bool Parser::ParseConfig(const std::string& path) {
+    if (is_dir(path.c_str())) {
+        return ParseConfigDir(path);
+    }
+    return ParseConfigFile(path);
 }
 
 }  // namespace init
diff --git a/init/parser.h b/init/parser.h
index 86e4c57..fd65ad6 100644
--- a/init/parser.h
+++ b/init/parser.h
@@ -14,27 +14,77 @@
  * limitations under the License.
  */
 
-#ifndef PARSER_H_
-#define PARSER_H_
+#ifndef _INIT_PARSER_H_
+#define _INIT_PARSER_H_
 
-#define T_EOF 0
-#define T_TEXT 1
-#define T_NEWLINE 2
+#include <map>
+#include <memory>
+#include <string>
+#include <vector>
+
+//  SectionParser is an interface that can parse a given 'section' in init.
+//
+//  You can implement up to 4 functions below, with ParseSection() being mandatory.
+//  The first two function return bool with false indicating a failure and has a std::string* err
+//  parameter into which an error string can be written.  It will be reported along with the
+//  filename and line number of where the error occurred.
+//
+//  1) bool ParseSection(std::vector<std::string>&& args, const std::string& filename,
+//                       int line, std::string* err)
+//    This function is called when a section is first encountered.
+//
+//  2) bool ParseLineSection(std::vector<std::string>&& args, int line, std::string* err)
+//    This function is called on each subsequent line until the next section is encountered.
+//
+//  3) bool EndSection()
+//    This function is called either when a new section is found or at the end of the file.
+//    It indicates that parsing of the current section is complete and any relevant objects should
+//    be committed.
+//
+//  4) bool EndFile()
+//    This function is called at the end of the file.
+//    It indicates that the parsing has completed and any relevant objects should be committed.
 
 namespace android {
 namespace init {
 
-struct parse_state
-{
-    char *ptr;
-    char *text;
-    int line;
-    int nexttoken;
+class SectionParser {
+  public:
+    virtual ~SectionParser() {}
+    virtual bool ParseSection(std::vector<std::string>&& args, const std::string& filename,
+                              int line, std::string* err) = 0;
+    virtual bool ParseLineSection(std::vector<std::string>&&, int, std::string*) { return true; };
+    virtual void EndSection(){};
+    virtual void EndFile(){};
 };
 
-int next_token(struct parse_state *state);
+class Parser {
+  public:
+    //  LineCallback is the type for callbacks that can parse a line starting with a given prefix.
+    //
+    //  They take the form of bool Callback(std::vector<std::string>&& args, std::string* err)
+    //
+    //  Similar to ParseSection() and ParseLineSection(), this function returns bool with false
+    //  indicating a failure and has an std::string* err parameter into which an error string can
+    //  be written.
+    using LineCallback = std::function<bool(std::vector<std::string>&&, std::string*)>;
+
+    Parser();
+
+    bool ParseConfig(const std::string& path);
+    void AddSectionParser(const std::string& name, std::unique_ptr<SectionParser> parser);
+    void AddSingleLineParser(const std::string& prefix, LineCallback callback);
+
+  private:
+    void ParseData(const std::string& filename, const std::string& data);
+    bool ParseConfigFile(const std::string& path);
+    bool ParseConfigDir(const std::string& path);
+
+    std::map<std::string, std::unique_ptr<SectionParser>> section_parsers_;
+    std::vector<std::pair<std::string, LineCallback>> line_callbacks_;
+};
 
 }  // namespace init
 }  // namespace android
 
-#endif /* PARSER_H_ */
+#endif
diff --git a/init/service.h b/init/service.h
index 62a3299..10e19d9 100644
--- a/init/service.h
+++ b/init/service.h
@@ -30,8 +30,8 @@
 #include "action.h"
 #include "capabilities.h"
 #include "descriptors.h"
-#include "init_parser.h"
 #include "keyword_map.h"
+#include "parser.h"
 
 #define SVC_DISABLED 0x001        // do not autostart with class
 #define SVC_ONESHOT 0x002         // do not restart on exit
diff --git a/init/service_test.cpp b/init/service_test.cpp
index 44f28a3..123c8a5 100644
--- a/init/service_test.cpp
+++ b/init/service_test.cpp
@@ -23,6 +23,8 @@
 
 #include <gtest/gtest.h>
 
+#include "util.h"
+
 namespace android {
 namespace init {
 
@@ -71,5 +73,123 @@
     EXPECT_FALSE(service_in_old_memory->process_cgroup_empty());
 }
 
+TEST(service, make_exec_oneshot_service_invalid_syntax) {
+    ServiceManager& sm = ServiceManager::GetInstance();
+    std::vector<std::string> args;
+    // Nothing.
+    ASSERT_EQ(nullptr, sm.MakeExecOneshotService(args));
+
+    // No arguments to 'exec'.
+    args.push_back("exec");
+    ASSERT_EQ(nullptr, sm.MakeExecOneshotService(args));
+
+    // No command in "exec --".
+    args.push_back("--");
+    ASSERT_EQ(nullptr, sm.MakeExecOneshotService(args));
+}
+
+TEST(service, make_exec_oneshot_service_too_many_supplementary_gids) {
+    ServiceManager& sm = ServiceManager::GetInstance();
+    std::vector<std::string> args;
+    args.push_back("exec");
+    args.push_back("seclabel");
+    args.push_back("root");  // uid.
+    args.push_back("root");  // gid.
+    for (int i = 0; i < NR_SVC_SUPP_GIDS; ++i) {
+        args.push_back("root");  // Supplementary gid.
+    }
+    args.push_back("--");
+    args.push_back("/system/bin/id");
+    ASSERT_EQ(nullptr, sm.MakeExecOneshotService(args));
+}
+
+static void Test_make_exec_oneshot_service(bool dash_dash, bool seclabel, bool uid, bool gid,
+                                           bool supplementary_gids) {
+    ServiceManager& sm = ServiceManager::GetInstance();
+    std::vector<std::string> args;
+    args.push_back("exec");
+    if (seclabel) {
+        args.push_back("u:r:su:s0");  // seclabel
+        if (uid) {
+            args.push_back("log");  // uid
+            if (gid) {
+                args.push_back("shell");  // gid
+                if (supplementary_gids) {
+                    args.push_back("system");  // supplementary gid 0
+                    args.push_back("adb");     // supplementary gid 1
+                }
+            }
+        }
+    }
+    if (dash_dash) {
+        args.push_back("--");
+    }
+    args.push_back("/system/bin/toybox");
+    args.push_back("id");
+    Service* svc = sm.MakeExecOneshotService(args);
+    ASSERT_NE(nullptr, svc);
+
+    if (seclabel) {
+        ASSERT_EQ("u:r:su:s0", svc->seclabel());
+    } else {
+        ASSERT_EQ("", svc->seclabel());
+    }
+    if (uid) {
+        uid_t decoded_uid;
+        std::string err;
+        ASSERT_TRUE(DecodeUid("log", &decoded_uid, &err));
+        ASSERT_EQ(decoded_uid, svc->uid());
+    } else {
+        ASSERT_EQ(0U, svc->uid());
+    }
+    if (gid) {
+        uid_t decoded_uid;
+        std::string err;
+        ASSERT_TRUE(DecodeUid("shell", &decoded_uid, &err));
+        ASSERT_EQ(decoded_uid, svc->gid());
+    } else {
+        ASSERT_EQ(0U, svc->gid());
+    }
+    if (supplementary_gids) {
+        ASSERT_EQ(2U, svc->supp_gids().size());
+        uid_t decoded_uid;
+        std::string err;
+        ASSERT_TRUE(DecodeUid("system", &decoded_uid, &err));
+        ASSERT_EQ(decoded_uid, svc->supp_gids()[0]);
+        ASSERT_TRUE(DecodeUid("adb", &decoded_uid, &err));
+        ASSERT_EQ(decoded_uid, svc->supp_gids()[1]);
+    } else {
+        ASSERT_EQ(0U, svc->supp_gids().size());
+    }
+
+    ASSERT_EQ(static_cast<std::size_t>(2), svc->args().size());
+    ASSERT_EQ("/system/bin/toybox", svc->args()[0]);
+    ASSERT_EQ("id", svc->args()[1]);
+}
+
+TEST(service, make_exec_oneshot_service_with_everything) {
+    Test_make_exec_oneshot_service(true, true, true, true, true);
+}
+
+TEST(service, make_exec_oneshot_service_with_seclabel_uid_gid) {
+    Test_make_exec_oneshot_service(true, true, true, true, false);
+}
+
+TEST(service, make_exec_oneshot_service_with_seclabel_uid) {
+    Test_make_exec_oneshot_service(true, true, true, false, false);
+}
+
+TEST(service, make_exec_oneshot_service_with_seclabel) {
+    Test_make_exec_oneshot_service(true, true, false, false, false);
+}
+
+TEST(service, make_exec_oneshot_service_with_just_command) {
+    Test_make_exec_oneshot_service(true, false, false, false, false);
+}
+
+TEST(service, make_exec_oneshot_service_with_just_command_no_dash) {
+    Test_make_exec_oneshot_service(false, false, false, false, false);
+}
+
 }  // namespace init
 }  // namespace android
diff --git a/init/tokenizer.cpp b/init/tokenizer.cpp
new file mode 100644
index 0000000..f8d9b6b
--- /dev/null
+++ b/init/tokenizer.cpp
@@ -0,0 +1,124 @@
+#include "tokenizer.h"
+
+namespace android {
+namespace init {
+
+int next_token(struct parse_state *state)
+{
+    char *x = state->ptr;
+    char *s;
+
+    if (state->nexttoken) {
+        int t = state->nexttoken;
+        state->nexttoken = 0;
+        return t;
+    }
+
+    for (;;) {
+        switch (*x) {
+        case 0:
+            state->ptr = x;
+            return T_EOF;
+        case '\n':
+            x++;
+            state->ptr = x;
+            return T_NEWLINE;
+        case ' ':
+        case '\t':
+        case '\r':
+            x++;
+            continue;
+        case '#':
+            while (*x && (*x != '\n')) x++;
+            if (*x == '\n') {
+                state->ptr = x+1;
+                return T_NEWLINE;
+            } else {
+                state->ptr = x;
+                return T_EOF;
+            }
+        default:
+            goto text;
+        }
+    }
+
+textdone:
+    state->ptr = x;
+    *s = 0;
+    return T_TEXT;
+text:
+    state->text = s = x;
+textresume:
+    for (;;) {
+        switch (*x) {
+        case 0:
+            goto textdone;
+        case ' ':
+        case '\t':
+        case '\r':
+            x++;
+            goto textdone;
+        case '\n':
+            state->nexttoken = T_NEWLINE;
+            x++;
+            goto textdone;
+        case '"':
+            x++;
+            for (;;) {
+                switch (*x) {
+                case 0:
+                        /* unterminated quoted thing */
+                    state->ptr = x;
+                    return T_EOF;
+                case '"':
+                    x++;
+                    goto textresume;
+                default:
+                    *s++ = *x++;
+                }
+            }
+            break;
+        case '\\':
+            x++;
+            switch (*x) {
+            case 0:
+                goto textdone;
+            case 'n':
+                *s++ = '\n';
+                break;
+            case 'r':
+                *s++ = '\r';
+                break;
+            case 't':
+                *s++ = '\t';
+                break;
+            case '\\':
+                *s++ = '\\';
+                break;
+            case '\r':
+                    /* \ <cr> <lf> -> line continuation */
+                if (x[1] != '\n') {
+                    x++;
+                    continue;
+                }
+            case '\n':
+                    /* \ <lf> -> line continuation */
+                state->line++;
+                x++;
+                    /* eat any extra whitespace */
+                while((*x == ' ') || (*x == '\t')) x++;
+                continue;
+            default:
+                    /* unknown escape -- just copy */
+                *s++ = *x++;
+            }
+            continue;
+        default:
+            *s++ = *x++;
+        }
+    }
+    return T_EOF;
+}
+
+}  // namespace init
+}  // namespace android
diff --git a/init/tokenizer.h b/init/tokenizer.h
new file mode 100644
index 0000000..72c08ef
--- /dev/null
+++ b/init/tokenizer.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _INIT_TOKENIZER_H_
+#define _INIT_TOKENIZER_H_
+
+#define T_EOF 0
+#define T_TEXT 1
+#define T_NEWLINE 2
+
+namespace android {
+namespace init {
+
+struct parse_state
+{
+    char *ptr;
+    char *text;
+    int line;
+    int nexttoken;
+};
+
+int next_token(struct parse_state *state);
+
+}  // namespace init
+}  // namespace android
+
+#endif
diff --git a/init/ueventd_parser.h b/init/ueventd_parser.h
index 592df63..51d83ef 100644
--- a/init/ueventd_parser.h
+++ b/init/ueventd_parser.h
@@ -21,7 +21,7 @@
 #include <vector>
 
 #include "devices.h"
-#include "init_parser.h"
+#include "parser.h"
 
 namespace android {
 namespace init {