Support distribution of RPL patterns

Cargo.toml

@@ -22,6 +22,7 @@ rpl_mir_graph = { path = "./crates/rpl_mir_graph" }
 rpl_mir_transform = { path = "./crates/rpl_mir_transform" }
 rpl_utils = { path = "./crates/rpl_utils" }
 rpl_meta = { path = "./crates/rpl_meta" }
+rpl_config = { path = "./crates/rpl_config" }
 rpl_constraints = { path = "./crates/rpl_constraints" }
 rpl_resolve = { path = "./crates/rpl_resolve" }
 rustc_tools_util = "0.3.0"
@@ -90,6 +91,7 @@ path = "src/driver.rs"
 [dependencies]
 rpl_interface.workspace = true
 rpl_meta.workspace = true
+rpl_config.workspace = true
 rustc_tools_util.workspace = true
 color-print = "0.3.4"
 anstream = "0.6.0"

crates/rpl_config/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "rpl_config"
+version.workspace = true
+description.workspace = true
+repository.workspace = true
+license.workspace = true
+keywords.workspace = true
+edition.workspace = true
+
+[dependencies]
+cargo_metadata = "0.15.4"
+serde.workspace = true
+serde_json.workspace = true
+toml.workspace = true
+thiserror.workspace = true

crates/rpl_config/src/lib.rs

@@ -0,0 +1,74 @@
+use std::path::{Path, PathBuf};
+
+use serde::Deserialize;
+
+mod patterns;
+mod run;
+mod util;
+
+#[derive(Debug, thiserror::Error)]
+pub enum ConfigError {
+    #[error("failed to read {path}: {source}")]
+    Io { path: PathBuf, source: Box<std::io::Error> },
+    #[error("failed to parse {path}: {source}")]
+    Toml {
+        path: PathBuf,
+        source: Box<toml::de::Error>,
+    },
+    #[error("cargo metadata failed: {0}")]
+    CargoMetadata(#[from] Box<cargo_metadata::Error>),
+    #[error("rpl.toml not found at {path}")]
+    ConfigNotFound { path: PathBuf },
+    #[error("rpl.toml defines no pattern groups")]
+    NoGroups,
+    #[error("duplicate pattern group name `{name}`")]
+    DuplicateGroup { name: String },
+    #[error("unknown pattern group `{name}`")]
+    UnknownGroup { name: String },
+    #[error("invalid remote group reference `{spec}`; expected `crate::group`")]
+    InvalidRemoteGroup { spec: String },
+    #[error("crate `{crate_name}` not found in cargo metadata")]
+    CrateNotFound { crate_name: String },
+    #[error("multiple crates named `{crate_name}` found; disambiguation not supported")]
+    AmbiguousCrate { crate_name: String },
+    #[error("crate `{crate_name}` does not publish RPL metadata")]
+    MissingRplMetadata { crate_name: String },
+    #[error("crate `{crate_name}` has invalid RPL metadata: {error}")]
+    InvalidRplMetadata { crate_name: String, error: String },
+    #[error("crate `{crate_name}` does not define RPL group `{group}`")]
+    MissingRemoteGroup { crate_name: String, group: String },
+    #[error("pattern group name cannot be empty")]
+    EmptyGroupName,
+    #[error("pattern path is not valid unicode: {path}")]
+    NonUnicodePath { path: PathBuf },
+    #[error("pattern paths cannot be joined for environment variable: {source}")]
+    InvalidPatternPathList { source: Box<std::env::JoinPathsError> },
+}
+
+#[derive(Debug, Deserialize)]
+struct RplConfig {
+    run: Option<run::RunConfig>,
+    patterns: Option<patterns::PatternsConfig>,
+}
+
+#[derive(Debug)]
+pub struct Config {
+    pub patterns_env: Option<String>,
+    pub inline_mir: Option<bool>,
+}
+
+pub fn load_config(manifest_path: Option<&Path>, selected_groups: &[String]) -> Result<Config, ConfigError> {
+    let base_dir = util::resolve_base_dir(manifest_path)?;
+    let config_path = base_dir.join("rpl.toml");
+    let config = if config_path.exists() {
+        Some(util::read_config(&config_path)?)
+    } else {
+        None
+    };
+    let inline_mir = run::load_inline_mir(config.as_ref());
+    let patterns_env = patterns::load_patterns_env(manifest_path, selected_groups, config.as_ref())?;
+    Ok(Config {
+        patterns_env,
+        inline_mir,
+    })
+}