Generate methods for Widgets

lvgl-codegen/Cargo.toml

@@ -1,12 +1,26 @@
 [package]
 name = "lvgl-codegen"
 version = "0.1.0"
+description = "Code generation based on LVGL source code"
 authors = ["Rafael Caricio <rafael@caricio.com>"]
 edition = "2018"
+license = "MIT"
 publish = false
+build = "build.rs"
+
+[lib]
+name = "lvgl_codegen"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-tera = "1.3.0"
 regex = "1.3.9"
+quote = "1.0.7"
+lazy_static = "1.4.0"
+clang = { path = "../../clang-rs" }
+itertools = "0.9.0"
+proc-macro2 = "1.0.18"
+syn = "1.0.31"
+
+[build-dependencies]
+cc = "1.0.50"

lvgl-codegen/build.rs

@@ -0,0 +1,69 @@
+use cc::Build;
+use std::process::Command;
+use std::{env, fs, path::Path, path::PathBuf};
+
+static CONFIG_NAME: &str = "DEP_LV_CONFIG_PATH";
+
+fn main() {
+    let project_dir = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap())
+        .canonicalize()
+        .unwrap();
+    let lvgl_sys = project_dir.join("..").join("lvgl-sys");
+    let vendor = lvgl_sys.join("vendor");
+    let lvgl_top_path = vendor.join("lvgl");
+    let lvgl_src_path = lvgl_top_path.join("src");
+    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
+
+    let lv_config_dir = {
+        let raw_path = env::var(CONFIG_NAME).unwrap_or_else(|_| {
+            panic!(
+                "The environment variable {} is required to be defined",
+                CONFIG_NAME
+            );
+        });
+        let conf_path = PathBuf::from(raw_path);
+
+        if !conf_path.exists() {
+            panic!(format!(
+                "Directory referenced by {} needs to exist",
+                CONFIG_NAME
+            ));
+        }
+        if !conf_path.is_dir() {
+            panic!(format!("{} needs to be a directory", CONFIG_NAME));
+        }
+        if !conf_path.join("lv_conf.h").exists() {
+            panic!(format!(
+                "Directory referenced by {} needs to contain a file called lv_conf.h",
+                CONFIG_NAME
+            ));
+        }
+
+        println!(
+            "cargo:rerun-if-changed={}",
+            conf_path.join("lv_conf.h").to_str().unwrap()
+        );
+        conf_path
+    };
+
+    let build = Build::new();
+    let tool = build.get_compiler();
+    let preprocessed = Command::new(tool.path().to_str().unwrap())
+        .args(&[
+            "-E",
+            "-std=c99",
+            "-DLV_CONF_INCLUDE_SIMPLE",
+            "-I",
+            lvgl_top_path.to_string_lossy().as_ref(),
+            "-I",
+            lvgl_src_path.to_string_lossy().as_ref(),
+            "-I",
+            lv_config_dir.to_string_lossy().as_ref(),
+            lvgl_top_path.join("lvgl.h").to_string_lossy().as_ref(),
+        ])
+        .output()
+        .unwrap();
+
+    let content = String::from_utf8(preprocessed.stdout).unwrap();
+    fs::write(out_path.join("lvgl_full.c"), content).unwrap();
+}

lvgl-codegen/src/lib.rs

@@ -0,0 +1,396 @@
+use clang::{Clang, Entity, EntityKind, Index, Type};
+use lazy_static::lazy_static;
+use proc_macro2::TokenStream;
+use quote::format_ident;
+use quote::quote;
+use regex::Regex;
+use std::collections::HashMap;
+use std::error::Error;
+
+type CGResult<T> = Result<T, Box<dyn Error>>;
+
+const LIB_PREFIX: &str = "lv_";
+
+lazy_static! {
+    static ref TYPE_MAPPINGS: HashMap<&'static str, &'static str> = [
+        ("uint16_t", "u16"),
+        ("int32_t", "i32"),
+        ("uint8_t", "u8"),
+        ("bool", "bool")
+    ]
+    .iter()
+    .cloned()
+    .collect();
+}
+
+#[derive(Debug, Copy, Clone)]
+pub enum WrapperError {
+    Skip,
+}
+
+pub type WrapperResult<T> = Result<T, WrapperError>;
+
+pub trait Rusty {
+    type Parent;
+
+    fn code(&self, parent: &Self::Parent) -> WrapperResult<TokenStream>;
+}
+
+#[derive(Clone, Eq, PartialEq)]
+pub struct LvWidget {
+    name: String,
+    methods: Vec<LvFunc>,
+}
+
+#[derive(Clone, Eq, PartialEq)]
+pub struct LvFunc {
+    name: String,
+    args: Vec<LvArg>,
+    ret: Option<LvType>,
+}
+
+impl LvFunc {
+    pub fn new(name: String, args: Vec<LvArg>, ret: Option<LvType>) -> Self {
+        Self { name, args, ret }
+    }
+}
+
+impl Rusty for LvFunc {
+    type Parent = LvWidget;
+
+    fn code(&self, parent: &Self::Parent) -> WrapperResult<TokenStream> {
+        let templ = format!("{}{}_", LIB_PREFIX, parent.name.as_str());
+        let new_name = self.name.replace(templ.as_str(), "");
+        let func_name = format_ident!("{}", new_name);
+        let original_func_name = format_ident!("{}", self.name.as_str());
+
+        // Make sure all argumets can be generated, skip the first arg (self)!
+        for arg in self.args.iter().skip(1) {
+            arg.code(self)?;
+        }
+
+        let args_decl = self
+            .args
+            .iter()
+            .enumerate()
+            .fold(quote!(), |mut args, (i, arg)| {
+                // if first arg is `const`, then it should be immutable
+                let next_arg = if i == 0 {
+                    if arg.get_type().is_const() {
+                        quote!(&self)
+                    } else {
+                        quote!(&mut self)
+                    }
+                } else {
+                    arg.code(self).unwrap()
+                };
+                if args.is_empty() {
+                    quote! {
+                        #next_arg
+                    }
+                } else {
+                    quote! {
+                        #args, #next_arg
+                    }
+                }
+            });
+
+        let args_call = self
+            .args
+            .iter()
+            .enumerate()
+            .fold(quote!(), |mut args, (i, arg)| {
+                // if first arg is `const`, then it should be immutable
+                let next_arg = if i == 0 {
+                    quote!(self.core.raw()?.as_mut())
+                } else {
+                    let var = format_ident!("{}", arg.name.as_str());
+                    quote!(#var)
+                };
+                if args.is_empty() {
+                    quote! {
+                        #next_arg
+                    }
+                } else {
+                    quote! {
+                        #args, #next_arg
+                    }
+                }
+            });
+
+        // TODO: Handle methods that return types
+        Ok(quote! {
+            pub fn #func_name(#args_decl) -> LvResult<()> {
+                unsafe {
+                    lvgl_sys::#original_func_name(#args_call);
+                }
+                Ok(())
+            }
+        })
+    }
+}
+
+impl From<Entity<'_>> for LvFunc {
+    fn from(entity: Entity) -> Self {
+        let result = entity.get_result_type().unwrap().get_display_name();
+        let ret_type = match result.as_str() {
+            "void" => None,
+            _ => Some(LvType::new(result)),
+        };
+        Self::new(
+            entity.get_name().unwrap(),
+            entity
+                .get_arguments()
+                .unwrap()
+                .iter()
+                .map(|e| e.into())
+                .collect::<Vec<LvArg>>(),
+            ret_type,
+        )
+    }
+}
+
+#[derive(Clone, Eq, PartialEq)]
+pub struct LvArg {
+    name: String,
+    typ: LvType,
+}
+
+impl LvArg {
+    pub fn new(name: String, typ: LvType) -> Self {
+        Self { name, typ }
+    }
+
+    pub fn get_type(&self) -> &LvType {
+        &self.typ
+    }
+}
+
+impl Rusty for LvArg {
+    type Parent = LvFunc;
+
+    fn code(&self, parent: &Self::Parent) -> WrapperResult<TokenStream> {
+        let name = format_ident!("{}", self.name.as_str());
+        let typ = self.typ.code(self)?;
+        Ok(quote! {
+            #name: #typ
+        })
+    }
+}
+
+impl From<&Entity<'_>> for LvArg {
+    fn from(entity: &Entity) -> Self {
+        Self::new(
+            entity.get_name().unwrap(),
+            entity.get_type().unwrap().into(),
+        )
+    }
+}
+
+#[derive(Clone, Eq, PartialEq)]
+pub struct LvType {
+    typ: String,
+}
+
+impl LvType {
+    pub fn new(typ: String) -> Self {
+        Self { typ }
+    }
+
+    pub fn is_const(&self) -> bool {
+        self.typ.starts_with("const ")
+    }
+}
+
+impl Rusty for LvType {
+    type Parent = LvArg;
+
+    fn code(&self, _parent: &Self::Parent) -> WrapperResult<TokenStream> {
+        match TYPE_MAPPINGS.get(self.typ.as_str()) {
+            Some(name) => {
+                let ident = format_ident!("{}", name);
+                Ok(quote! {
+                    #ident
+                })
+            }
+            None => Err(WrapperError::Skip),
+        }
+    }
+}
+
+impl From<Type<'_>> for LvType {
+    fn from(ty: Type) -> Self {
+        Self::new(ty.get_display_name())
+    }
+}
+
+pub struct CodeGen {
+    functions: Vec<LvFunc>,
+    widgets: Vec<LvWidget>,
+}
+
+impl CodeGen {
+    pub fn new() -> CGResult<Self> {
+        let functions = Self::load_function_definitions()?;
+        let widgets = Self::extract_widgets(&functions)?;
+        Ok(Self { functions, widgets })
+    }
+
+    fn extract_widgets(functions: &Vec<LvFunc>) -> CGResult<Vec<LvWidget>> {
+        let widget_names = Self::get_widget_names(functions);
+
+        let widgets = functions.iter().fold(HashMap::new(), |mut ws, f| {
+            for widget_name in &widget_names {
+                if f.name
+                    .starts_with(format!("{}{}", LIB_PREFIX, widget_name).as_str())
+                {
+                    ws.entry(widget_name.clone())
+                        .or_insert_with(|| LvWidget {
+                            name: widget_name.clone(),
+                            methods: Vec::new(),
+                        })
+                        .methods
+                        .push(f.clone())
+                }
+            }
+            ws
+        });
+
+        Ok(widgets.values().map(|v| v.clone()).collect())
+    }
+
+    fn get_widget_names(functions: &Vec<LvFunc>) -> Vec<String> {
+        let reg = format!("^{}([^_]+)_create$", LIB_PREFIX);
+        let create_func = Regex::new(reg.as_str()).unwrap();
+
+        functions
+            .iter()
+            .filter(|e| create_func.is_match(e.name.as_str()) && e.args.len() == 2)
+            .filter_map(|f| {
+                Some(String::from(
+                    create_func
+                        .captures(f.name.as_str())
+                        .unwrap()
+                        .get(1)
+                        .unwrap()
+                        .as_str(),
+                ))
+            })
+            .collect::<Vec<_>>()
+    }
+
+    pub fn load_function_definitions() -> CGResult<Vec<LvFunc>> {
+        let clang = Clang::new()?;
+        let index = Index::new(&clang, false, false);
+        let tu = index
+            .parser(concat!(env!("OUT_DIR"), "/lvgl_full.c"))
+            .parse()?;
+        let entities = tu
+            .get_entity()
+            .get_children()
+            .into_iter()
+            .filter(|e| e.get_kind() == EntityKind::FunctionDecl)
+            .filter(|e| e.get_name().is_some())
+            .map(|e| e.into())
+            .filter(|e: &LvFunc| e.name.starts_with(LIB_PREFIX))
+            .collect::<Vec<_>>();
+        Ok(entities)
+    }
+
+    pub fn get_function_names(&self) -> CGResult<Vec<String>> {
+        Ok(self.functions.iter().map(|f| f.name.clone()).collect())
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use crate::{CodeGen, LvArg, LvFunc, LvType, LvWidget, Rusty};
+    use quote::quote;
+
+    #[test]
+    fn can_list_functions() {
+        let lv = CodeGen::new().unwrap();
+        let func = String::from("lv_obj_create");
+        let func_names = lv.get_function_names().unwrap();
+        assert!(func_names.contains(&func));
+    }
+
+    #[test]
+    fn can_identify_widgets_from_function_names() {
+        let funcs = vec![
+            LvFunc::new(
+                "lv_obj_create".to_string(),
+                vec![
+                    LvArg::new("parent".to_string(), LvType::new("abc".to_string())),
+                    LvArg::new("copy_from".to_string(), LvType::new("bcf".to_string())),
+                ],
+                None,
+            ),
+            LvFunc::new(
+                "lv_btn_create".to_string(),
+                vec![
+                    LvArg::new("parent".to_string(), LvType::new("abc".to_string())),
+                    LvArg::new("copy_from".to_string(), LvType::new("bcf".to_string())),
+                ],
+                None,
+            ),
+            LvFunc::new(
+                "lv_do_something".to_string(),
+                vec![
+                    LvArg::new("parent".to_string(), LvType::new("abc".to_string())),
+                    LvArg::new("copy_from".to_string(), LvType::new("bcf".to_string())),
+                ],
+                None,
+            ),
+            LvFunc::new(
+                "lv_invalid_create".to_string(),
+                vec![LvArg::new(
+                    "parent".to_string(),
+                    LvType::new("abc".to_string()),
+                )],
+                None,
+            ),
+            LvFunc::new(
+                "lv_cb_create".to_string(),
+                vec![
+                    LvArg::new("parent".to_string(), LvType::new("abc".to_string())),
+                    LvArg::new("copy_from".to_string(), LvType::new("bcf".to_string())),
+                ],
+                None,
+            ),
+        ];
+
+        let widget_names = CodeGen::get_widget_names(&funcs);
+
+        assert_eq!(widget_names.len(), 3);
+    }
+
+    #[test]
+    fn generate_method_wrapper() {
+        // void lv_arc_set_bg_end_angle(lv_obj_t * arc, uint16_t end);
+        let arc_set_bg_end_angle = LvFunc::new(
+            "lv_arc_set_bg_end_angle".to_string(),
+            vec![
+                LvArg::new("arc".to_string(), LvType::new("lv_obj_t *".to_string())),
+                LvArg::new("end".to_string(), LvType::new("uint16_t".to_string())),
+            ],
+            None,
+        );
+        let arc_widget = LvWidget {
+            name: "arc".to_string(),
+            methods: vec![],
+        };
+
+        let code = arc_set_bg_end_angle.code(&arc_widget).unwrap();
+        let expected_code = quote! {
+            pub fn set_bg_end_angle(&mut self, end: u16) -> LvResult<()> {
+                unsafe {
+                    lvgl_sys::lv_arc_set_bg_end_angle(self.core.raw()?.as_mut(), end);
+                }
+                Ok(())
+            }
+        };
+
+        assert_eq!(code.to_string(), expected_code.to_string());
+    }
+}

lvgl-codegen/src/main.rs

@@ -1,35 +0,0 @@
-use regex::Regex;
-use tera::{Context, Tera};
-
-fn main() {
-    let re = Regex::new(r"\((?P<prop_name>[^,]+), (?P<func_name>[^,]+), (?P<value_type>[^,]+), (?P<style_type>[^)]+), [a-z]+\)").unwrap();
-
-    let input = include_str!("../../lvgl-sys/vendor/lvgl/src/lv_core/lv_obj_style_dec.h");
-
-    let mut tera = Tera::default();
-    tera.add_raw_template("styles.rs", include_str!("../templates/style.rs.j2"))
-        .unwrap();
-
-    for line in input.lines() {
-        if !line.starts_with("_LV_OBJ_STYLE_SET_GET_DECLARE") {
-            continue;
-        }
-
-        if let Some(cap) = re.captures(line) {
-            let style_type = cap.get(4).unwrap().as_str().to_string();
-            if style_type.eq("_ptr") {
-                // Just a few, we will take care of this manually.
-                continue;
-            }
-
-            let value_type = cap.get(3).unwrap().as_str().to_string();
-
-            let mut ctx = Context::new();
-            ctx.insert("prop_name", cap.get(1).unwrap().as_str());
-            ctx.insert("func_name", cap.get(2).unwrap().as_str());
-            ctx.insert("value_type", value_type.as_str());
-            ctx.insert("style_type", style_type.as_str());
-            println!("{}", tera.render("styles.rs", &ctx).unwrap());
-        }
-    }
-}

lvgl-codegen/templates/style.rs.j2

@@ -1,33 +0,0 @@
-pub fn set_{{func_name}}(&mut self, state: State,
-
-    {% if style_type == "_color" %}
-    value: Color
-    {% elif style_type == "_int" %}
-    value: i16
-    {% elif style_type == "_ptr" %}
-    value: Any
-    {% elif style_type == "_opa" %}
-    value: Opacity
-    {% endif %}
-
-) {
-    let native_state: u32 = state.get_bits();
-    unsafe {
-        lvgl_sys::_lv_style_set{{style_type}}(
-            self.raw.as_mut(),
-            (lvgl_sys::LV_STYLE_{{prop_name}}
-            | (native_state << lvgl_sys::LV_STYLE_STATE_POS as u32)) as u16,
-
-            {% if style_type == "_color" %}
-                value.raw,
-            {% elif style_type == "_int" %}
-                value
-            {% elif style_type == "_opa" %}
-                value.into()
-            {% elif style_type == "_ptr" %}
-                value.into()
-            {% endif %}
-
-        );
-    }
-}