printbuf_to_formatter: Lossy display of non-UTF-8 printbufs

[bcachefs-tools-debian] / bch_bindgen / build.rs

diff --git a/bch_bindgen/build.rs b/bch_bindgen/build.rs
index facea217be40bbacf6241b29c2f65de3a47cfbf4..c9a90fcab25da4cefeb805bbd65a6caedac8abbc 100644 (file)
--- a/bch_bindgen/build.rs
+++ b/bch_bindgen/build.rs
@@ -1,4 +1,3 @@
-
 #[derive(Debug)]
 pub struct Fix753 {}
 impl bindgen::callbacks::ParseCallbacks for Fix753 {
@@ -19,9 +18,9 @@ fn main() {
         .expect("ENV Var 'CARGO_MANIFEST_DIR' Expected")
         .into();
 
-    let libbcachefs_inc_dir = std::path::Path::new("../c_src");
-
+    let urcu = pkg_config::probe_library("liburcu").expect("Failed to find urcu lib");
     let bindings = bindgen::builder()
+        .formatter(bindgen::Formatter::Prettyplease)
         .header(
             top_dir
                 .join("src")
@@ -29,11 +28,15 @@ fn main() {
                 .display()
                 .to_string(),
         )
-        .clang_arg(format!(
-            "-I{}",
-            libbcachefs_inc_dir.join("include").display()
-        ))
-        .clang_arg(format!("-I{}", libbcachefs_inc_dir.display()))
+        .clang_args(
+            urcu
+                .include_paths
+                .iter()
+                .map(|p| format!("-I{}", p.display())),
+        )
+        .clang_arg("-I..")
+        .clang_arg("-I../c_src")
+        .clang_arg("-I../include")
         .clang_arg("-DZSTD_STATIC_LINKING_ONLY")
         .clang_arg("-DNO_BCACHEFS_FS")
         .clang_arg("-D_GNU_SOURCE")
@@ -50,6 +53,8 @@ fn main() {
         .allowlist_function("cmd_.*")
         .allowlist_function(".*_cmds")
         .allowlist_function(".*bch2_.*")
+        .allowlist_function("bcache_fs_open")
+        .allowlist_function("bcache_fs_close")
         .allowlist_function("bio_.*")
         .allowlist_function("derive_passphrase")
         .allowlist_function("request_key")
@@ -57,14 +62,11 @@ fn main() {
         .allowlist_function("keyctl_search")
         .allowlist_function("match_string")
         .allowlist_function("printbuf.*")
-        .blocklist_type("bch_extent_ptr")
-        .blocklist_type("btree_node")
-        .blocklist_type("bch_extent_crc32")
         .blocklist_type("rhash_lock_head")
         .blocklist_type("srcu_struct")
         .allowlist_var("BCH_.*")
         .allowlist_var("KEY_SPEC_.*")
-        .allowlist_var("Fix753_FMODE_.*")
+        .allowlist_var("Fix753_.*")
         .allowlist_var("bch.*")
         .allowlist_var("__bch2.*")
         .allowlist_var("__BTREE_ITER.*")
@@ -89,9 +91,12 @@ fn main() {
         .parse_callbacks(Box::new(Fix753 {}))
         .generate()
         .expect("BindGen Generation Failiure: [libbcachefs_wrapper]");
-    bindings
-        .write_to_file(out_dir.join("bcachefs.rs"))
-        .expect("Writing to output file failed for: `bcachefs.rs`");
+
+    std::fs::write(
+        out_dir.join("bcachefs.rs"),
+        packed_and_align_fix(bindings.to_string()),
+    )
+    .expect("Writing to output file failed for: `bcachefs.rs`");
 
     let keyutils = pkg_config::probe_library("libkeyutils").expect("Failed to find keyutils lib");
     let bindings = bindgen::builder()
@@ -114,3 +119,41 @@ fn main() {
         .write_to_file(out_dir.join("keyutils.rs"))
         .expect("Writing to output file failed for: `keyutils.rs`");
 }
+
+// rustc has a limitation where it does not allow structs to have both a "packed" and "align"
+// attribute. This means that bindgen cannot copy all attributes from some C types, like struct
+// bkey, that are both packed and aligned.
+//
+// bindgen tries to handle this situation smartly and for many types it will only apply a
+// "packed(N)" attribute if that is good enough. However, there are a few types where bindgen
+// does end up generating both a packed(N) and align(N) attribute. These types can't be compiled
+// by rustc.
+//
+// To work around this, we can remove either the "packed" or "align" attribute. It happens that
+// for all the types with this problem in bcachefs, removing the "packed" attribute and keeping
+// the "align" attribute results in a type with the correct ABI.
+//
+// This function applies that transformation to the following bcachefs types that need it:
+//   - bkey
+//   - bch_extent_crc32
+//   - bch_extent_ptr
+//   - btree_node
+fn packed_and_align_fix(bindings: std::string::String) -> std::string::String {
+    bindings
+        .replace(
+            "#[repr(C, packed(8))]\n#[repr(align(8))]\n#[derive(Debug, Default, Copy, Clone)]\npub struct bkey {",
+            "#[repr(C, align(8))]\n#[derive(Debug, Default, Copy, Clone)]\npub struct bkey {",
+        )
+        .replace(
+            "#[repr(C, packed(8))]\n#[repr(align(8))]\n#[derive(Debug, Default, Copy, Clone)]\npub struct bch_extent_crc32 {",
+            "#[repr(C, align(8))]\n#[derive(Debug, Default, Copy, Clone)]\npub struct bch_extent_crc32 {",
+        )
+        .replace(
+            "#[repr(C, packed(8))]\n#[repr(align(8))]\n#[derive(Debug, Default, Copy, Clone)]\npub struct bch_extent_ptr {",
+            "#[repr(C, align(8))]\n#[derive(Debug, Default, Copy, Clone)]\npub struct bch_extent_ptr {",
+        )
+        .replace(
+            "#[repr(C, packed(8))]\npub struct btree_node {",
+            "#[repr(C, align(8))]\npub struct btree_node {",
+        )
+}