v0.2.96

build.rs

@@ -1,7 +1,64 @@
-use std::{env, fs, path::PathBuf};
+use std::{
+    env, fs,
+    path::{Path, PathBuf},
+};
+
+const FNV_OFFSET: u64 = 0xcbf29ce484222325;
+const FNV_PRIME: u64 = 0x100000001b3;
+
+fn hash_bytes(mut hash: u64, bytes: &[u8]) -> u64 {
+    for byte in bytes {
+        hash ^= u64::from(*byte);
+        hash = hash.wrapping_mul(FNV_PRIME);
+    }
+    hash
+}
+
+fn collect_files(root: &Path, dir: &Path, files: &mut Vec<PathBuf>) {
+    let mut entries = fs::read_dir(dir)
+        .unwrap_or_else(|error| panic!("failed to read {}: {error}", dir.display()))
+        .filter_map(Result::ok)
+        .map(|entry| entry.path())
+        .collect::<Vec<_>>();
+    entries.sort();
+    for path in entries {
+        if path.is_dir() {
+            collect_files(root, &path, files);
+        } else if path.is_file() {
+            println!(
+                "cargo:rerun-if-changed={}",
+                path.strip_prefix(root).unwrap_or(&path).display()
+            );
+            files.push(path);
+        }
+    }
+}
+
+fn asset_version(manifest_dir: &Path) -> String {
+    let mut files = Vec::new();
+    collect_files(manifest_dir, &manifest_dir.join("static"), &mut files);
+    collect_files(manifest_dir, &manifest_dir.join("lang"), &mut files);
+    files.sort();
+
+    let mut hash = FNV_OFFSET;
+    for path in files {
+        let relative = path.strip_prefix(manifest_dir).unwrap_or(&path);
+        hash = hash_bytes(hash, relative.to_string_lossy().as_bytes());
+        hash = hash_bytes(hash, &[0]);
+        let bytes = fs::read(&path)
+            .unwrap_or_else(|error| panic!("failed to read {}: {error}", path.display()));
+        hash = hash_bytes(hash, &bytes);
+        hash = hash_bytes(hash, &[0xff]);
+    }
+    format!(
+        "{}-{hash:016x}",
+        env::var("CARGO_PKG_VERSION").expect("CARGO_PKG_VERSION")
+    )
+}
 
 fn main() {
     println!("cargo:rerun-if-changed=lang");
+    println!("cargo:rerun-if-changed=static");
 
     let manifest_dir = PathBuf::from(env::var("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR"));
     let lang_dir = manifest_dir.join("lang");
@@ -31,5 +88,11 @@ fn main() {
     generated.push_str("];\n");
 
     let out_dir = PathBuf::from(env::var("OUT_DIR").expect("OUT_DIR"));
-    fs::write(out_dir.join("languages.rs"), generated).expect("failed to generate embedded languages");
+    fs::write(out_dir.join("languages.rs"), generated)
+        .expect("failed to generate embedded languages");
+
+    println!(
+        "cargo:rustc-env=RUSTPAD_ASSET_VERSION={}",
+        asset_version(&manifest_dir)
+    );
 }