flatbuffers: add definitions + build step

Cargo.toml

@@ -13,6 +13,8 @@ links = "protosol"
 
 [build-dependencies]
 prost-build = "0.11.9"
+flatc-rust = "0.2.0"
 
 [dependencies]
 prost = "0.11.9"
+flatbuffers = "25.9.23"

build.rs

@@ -1,4 +1,8 @@
-use std::{env, fs, path::{Path, PathBuf}};
+extern crate flatc_rust;
+use std::{
+    env, fs,
+    path::{Path, PathBuf},
+};
 
 /// Normalize path only on Windows, else just return unchanged.
 fn maybe_normalize_windows_path(path: &Path) -> PathBuf {
@@ -18,34 +22,74 @@ fn maybe_normalize_windows_path(path: &Path) -> PathBuf {
     }
 }
 
-fn main() -> Result<(), Box<dyn std::error::Error>> {
-    let proto_dir = PathBuf::from("proto");
+fn monitor_and_get_files(
+    dir: &PathBuf,
+    env_var: &str,
+    extension: &str,
+) -> Result<(Vec<PathBuf>, PathBuf), Box<dyn std::error::Error>> {
     let abs = env::current_dir()
         .expect("cwd")
-        .join(&proto_dir)
+        .join(dir)
         .canonicalize()
         .map(|p| maybe_normalize_windows_path(&p))
-        .expect("canonicalize proto dir");
+        .expect("canonicalize dir");
 
     println!("cargo:rerun-if-changed={}", abs.display());
-    println!("cargo:PROTO_DIR={}", abs.display());
+    println!("cargo:{}={}", env_var, abs.display());
 
-    let mut proto_files = vec![];
+    let mut files = vec![];
     for entry in fs::read_dir(&abs)? {
         let path = entry?.path();
-        if path.extension().and_then(|e| e.to_str()) == Some("proto") {
+        if path.extension().and_then(|e| e.to_str()) == Some(extension) {
             println!("cargo:rerun-if-changed={}", path.display());
-            proto_files.push(path);
+            files.push(path);
         }
     }
 
+    Ok((files, abs))
+}
+
+fn compile_protos() -> Result<(), Box<dyn std::error::Error>> {
+    let proto_dir = PathBuf::from("proto");
+    let (proto_files, abs) = monitor_and_get_files(&proto_dir, "PROTO_DIR", "proto")?;
+
     let out_dir = PathBuf::from(env::var("OUT_DIR")?);
     let mut config = prost_build::Config::new();
     config.out_dir(&out_dir);
     config.compile_protos(
-        &proto_files.iter().map(|p| p.display().to_string()).collect::<Vec<_>>(),
+        &proto_files
+            .iter()
+            .map(|p| p.display().to_string())
+            .collect::<Vec<_>>(),
         &[abs],
     )?;
 
     Ok(())
 }
+
+fn compile_flatbuffers() -> Result<(), Box<dyn std::error::Error>> {
+    let flatbuffers_dir = PathBuf::from("flatbuffers");
+    let (flatbuffers_files, abs) =
+        monitor_and_get_files(&flatbuffers_dir, "FLATBUFFERS_DIR", "fbs")?;
+
+    let out_dir = PathBuf::from(env::var("OUT_DIR")?);
+    flatc_rust::run(flatc_rust::Args {
+        lang: "rust",
+        inputs: flatbuffers_files
+            .iter()
+            .map(|p| p.as_path())
+            .collect::<Vec<_>>()
+            .as_slice(),
+        out_dir: out_dir.as_path(),
+        includes: &[abs.as_path()],
+        ..Default::default()
+    })?;
+
+    Ok(())
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    compile_protos()?;
+    compile_flatbuffers()?;
+    Ok(())
+}

flatbuffers/context.fbs

@@ -0,0 +1,36 @@
+// Generated from context.proto
+
+namespace org.solana.sealevel.v2;
+
+struct Pubkey {
+  address:[ubyte:32];
+}
+
+struct Signature {
+  signature:[ubyte:64];
+}
+
+struct Hash {
+  hash:[ubyte:32];
+}
+
+struct LtHash {
+  hash:[ushort:1024];
+}
+
+table FeatureSet {
+  features:[ulong];
+}
+
+table Account {
+  address:Pubkey (required);
+  lamports:ulong;
+  data:[ubyte] (required);
+  executable:bool;
+  owner:Pubkey (required);
+}
+
+table VoteAccount {
+  vote_account:Account (required);
+  stake:ulong;
+}

flatbuffers/elf.fbs

@@ -0,0 +1,28 @@
+// Generated from elf.proto
+
+include "metadata.fbs";
+include "context.fbs";
+
+namespace org.solana.sealevel.v2;
+
+table ELFLoaderCtx {
+  elf_data:[ubyte] (required);
+  features:FeatureSet (required);
+  deploy_checks:bool;
+}
+
+table ELFLoaderEffects {
+  err_code:ubyte;
+  rodata_hash:ulong;
+  text_cnt:ulong;
+  text_off:ulong;
+  entry_pc:ulong;
+  calldests_hash:ulong;
+}
+
+table ELFLoaderFixture {
+  metadata:FixtureMetadata (required);
+  input:ELFLoaderCtx (required);
+  output:ELFLoaderEffects (required);
+}
+

flatbuffers/metadata.fbs

@@ -0,0 +1,8 @@
+// Generated from metadata.proto
+
+namespace org.solana.sealevel.v2;
+
+table FixtureMetadata {
+  fn_entrypoint:string (required);
+}
+