Merge "aconfig: Add first iteration of cpp codegen to aconfig"

tools/aconfig/src/codegen_cpp.rs

@@ -0,0 +1,216 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+use anyhow::Result;
+use serde::Serialize;
+use tinytemplate::TinyTemplate;
+
+use crate::aconfig::{FlagState, Permission};
+use crate::cache::{Cache, Item};
+use crate::commands::OutputFile;
+
+pub fn generate_cpp_code(cache: &Cache) -> Result<OutputFile> {
+    let class_elements: Vec<ClassElement> = cache.iter().map(create_class_element).collect();
+    let readwrite = class_elements.iter().any(|item| item.readwrite);
+    let namespace = cache.namespace().to_lowercase();
+    let context = Context { namespace: namespace.clone(), readwrite, class_elements };
+    let mut template = TinyTemplate::new();
+    template.add_template("cpp_code_gen", include_str!("../templates/cpp.template"))?;
+    let contents = template.render("cpp_code_gen", &context)?;
+    let path = ["aconfig", &(namespace + ".h")].iter().collect();
+    Ok(OutputFile { contents: contents.into(), path })
+}
+
+#[derive(Serialize)]
+struct Context {
+    pub namespace: String,
+    pub readwrite: bool,
+    pub class_elements: Vec<ClassElement>,
+}
+
+#[derive(Serialize)]
+struct ClassElement {
+    pub readwrite: bool,
+    pub default_value: String,
+    pub flag_name: String,
+}
+
+fn create_class_element(item: &Item) -> ClassElement {
+    ClassElement {
+        readwrite: item.permission == Permission::ReadWrite,
+        default_value: if item.state == FlagState::Enabled {
+            "true".to_string()
+        } else {
+            "false".to_string()
+        },
+        flag_name: item.name.clone(),
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::aconfig::{FlagDeclaration, FlagState, FlagValue, Permission};
+    use crate::commands::Source;
+
+    #[test]
+    fn test_cpp_codegen_build_time_flag_only() {
+        let namespace = "my_namespace";
+        let mut cache = Cache::new(namespace.to_string()).unwrap();
+        cache
+            .add_flag_declaration(
+                Source::File("aconfig_one.txt".to_string()),
+                FlagDeclaration {
+                    name: "my_flag_one".to_string(),
+                    description: "buildtime disable".to_string(),
+                },
+            )
+            .unwrap();
+        cache
+            .add_flag_value(
+                Source::Memory,
+                FlagValue {
+                    namespace: namespace.to_string(),
+                    name: "my_flag_one".to_string(),
+                    state: FlagState::Disabled,
+                    permission: Permission::ReadOnly,
+                },
+            )
+            .unwrap();
+        cache
+            .add_flag_declaration(
+                Source::File("aconfig_two.txt".to_string()),
+                FlagDeclaration {
+                    name: "my_flag_two".to_string(),
+                    description: "buildtime enable".to_string(),
+                },
+            )
+            .unwrap();
+        cache
+            .add_flag_value(
+                Source::Memory,
+                FlagValue {
+                    namespace: namespace.to_string(),
+                    name: "my_flag_two".to_string(),
+                    state: FlagState::Enabled,
+                    permission: Permission::ReadOnly,
+                },
+            )
+            .unwrap();
+        let expect_content = r#"#ifndef my_namespace_HEADER_H
+        #define my_namespace_HEADER_H
+        #include "my_namespace.h"
+
+        namespace my_namespace {
+
+            class my_flag_one {
+                public:
+                    virtual const bool value() {
+                        return false;
+                    }
+            }
+
+            class my_flag_two {
+                public:
+                    virtual const bool value() {
+                        return true;
+                    }
+            }
+
+        }
+        #endif
+        "#;
+        let file = generate_cpp_code(&cache).unwrap();
+        assert_eq!("aconfig/my_namespace.h", file.path.to_str().unwrap());
+        assert_eq!(
+            expect_content.replace(' ', ""),
+            String::from_utf8(file.contents).unwrap().replace(' ', "")
+        );
+    }
+
+    #[test]
+    fn test_cpp_codegen_runtime_flag() {
+        let namespace = "my_namespace";
+        let mut cache = Cache::new(namespace.to_string()).unwrap();
+        cache
+            .add_flag_declaration(
+                Source::File("aconfig_one.txt".to_string()),
+                FlagDeclaration {
+                    name: "my_flag_one".to_string(),
+                    description: "buildtime disable".to_string(),
+                },
+            )
+            .unwrap();
+        cache
+            .add_flag_declaration(
+                Source::File("aconfig_two.txt".to_string()),
+                FlagDeclaration {
+                    name: "my_flag_two".to_string(),
+                    description: "runtime enable".to_string(),
+                },
+            )
+            .unwrap();
+        cache
+            .add_flag_value(
+                Source::Memory,
+                FlagValue {
+                    namespace: namespace.to_string(),
+                    name: "my_flag_two".to_string(),
+                    state: FlagState::Enabled,
+                    permission: Permission::ReadWrite,
+                },
+            )
+            .unwrap();
+        let expect_content = r#"#ifndef my_namespace_HEADER_H
+        #define my_namespace_HEADER_H
+        #include "my_namespace.h"
+
+        #include <server_configurable_flags/get_flags.h>
+        using namespace server_configurable_flags;
+
+        namespace my_namespace {
+
+            class my_flag_one {
+                public:
+                    virtual const bool value() {
+                        return GetServerConfigurableFlag(
+                            "my_namespace",
+                            "my_flag_one",
+                            "false") == "true";
+                    }
+            }
+
+            class my_flag_two {
+                public:
+                    virtual const bool value() {
+                        return GetServerConfigurableFlag(
+                            "my_namespace",
+                            "my_flag_two",
+                            "true") == "true";
+                    }
+            }
+
+        }
+        #endif
+        "#;
+        let file = generate_cpp_code(&cache).unwrap();
+        assert_eq!("aconfig/my_namespace.h", file.path.to_str().unwrap());
+        assert_eq!(
+            expect_content.replace(' ', ""),
+            String::from_utf8(file.contents).unwrap().replace(' ', "")
+        );
+    }
+}

tools/aconfig/src/commands.rs

@@ -24,6 +24,7 @@ use std::path::PathBuf;
 
 use crate::aconfig::{FlagDeclarations, FlagValue};
 use crate::cache::Cache;
+use crate::codegen_cpp::generate_cpp_code;
 use crate::codegen_java::generate_java_code;
 use crate::protos::ProtoParsedFlags;
 
@@ -91,10 +92,14 @@ pub fn create_cache(
     Ok(cache)
 }
 
-pub fn generate_code(cache: &Cache) -> Result<OutputFile> {
+pub fn create_java_lib(cache: &Cache) -> Result<OutputFile> {
     generate_java_code(cache)
 }
 
+pub fn create_cpp_lib(cache: &Cache) -> Result<OutputFile> {
+    generate_cpp_code(cache)
+}
+
 #[derive(Copy, Clone, Debug, PartialEq, Eq, ValueEnum)]
 pub enum DumpFormat {
     Text,

tools/aconfig/src/main.rs

@@ -26,6 +26,7 @@ use std::path::{Path, PathBuf};
 
 mod aconfig;
 mod cache;
+mod codegen_cpp;
 mod codegen_java;
 mod commands;
 mod protos;
@@ -48,6 +49,11 @@ fn cli() -> Command {
                 .arg(Arg::new("cache").long("cache").required(true))
                 .arg(Arg::new("out").long("out").required(true)),
         )
+        .subcommand(
+            Command::new("create-cpp-lib")
+                .arg(Arg::new("cache").long("cache").required(true))
+                .arg(Arg::new("out").long("out").required(true)),
+        )
         .subcommand(
             Command::new("dump")
                 .arg(Arg::new("cache").long("cache").required(true))
@@ -112,7 +118,15 @@ fn main() -> Result<()> {
             let file = fs::File::open(path)?;
             let cache = Cache::read_from_reader(file)?;
             let dir = PathBuf::from(get_required_arg::<String>(sub_matches, "out")?);
-            let generated_file = commands::generate_code(&cache)?;
+            let generated_file = commands::create_java_lib(&cache)?;
+            write_output_file_realtive_to_dir(&dir, &generated_file)?;
+        }
+        Some(("create-cpp-lib", sub_matches)) => {
+            let path = get_required_arg::<String>(sub_matches, "cache")?;
+            let file = fs::File::open(path)?;
+            let cache = Cache::read_from_reader(file)?;
+            let dir = PathBuf::from(get_required_arg::<String>(sub_matches, "out")?);
+            let generated_file = commands::create_cpp_lib(&cache)?;
             write_output_file_realtive_to_dir(&dir, &generated_file)?;
         }
         Some(("dump", sub_matches)) => {

tools/aconfig/templates/cpp.template

@@ -0,0 +1,25 @@
+#ifndef {namespace}_HEADER_H
+#define {namespace}_HEADER_H
+#include "{namespace}.h"
+{{ if readwrite }}
+#include <server_configurable_flags/get_flags.h>
+using namespace server_configurable_flags;
+{{ endif }}
+namespace {namespace} \{
+    {{ for item in class_elements}}
+    class {item.flag_name} \{
+        public:
+            virtual const bool value() \{
+                {{ if item.readwrite- }}
+                return GetServerConfigurableFlag(
+                    "{namespace}",
+                    "{item.flag_name}",
+                    "{item.default_value}") == "true";
+                {{ -else- }}
+                return {item.default_value};
+                {{ -endif }}
+            }
+    }
+    {{ endfor }}
+}
+#endif