Update bindgen to 0.71

This commit updates bindgen to 0.71. It also adds a test that verifies that the bundled bindings match the generated ones. Additionally it cleans up the generated bindings to only include items that are relevant for libpq

Cargo.toml

@@ -6,6 +6,7 @@ license = "MIT OR Apache-2.0"
 repository = "https://github.com/sgrif/pq-sys"
 links = "pq"
 build = "build.rs"
+edition = "2021"
 
 [workspace]
 members = ["pq-src"]
@@ -15,14 +16,19 @@ name = "pq_sys"
 
 [dependencies]
 pq-src = { path = "pq-src", version = ">=0.2, <0.4", optional = true , default-features = false }
+libc = "0.2.100"
 
 [build-dependencies]
 pkg-config = { version = "0.3.0", optional = true }
-bindgen = { version = "0.69.1", optional = true }
+bindgen = { version = "0.71.0", optional = true }
 
 [target.'cfg(target_env = "msvc")'.build-dependencies]
 vcpkg = "0.2.6"
 
+[dev-dependencies]
+similar-asserts = "1.6.0"
+bindgen = "0.71.0"
+
 [features]
 default = []
 bundled = ["bundled_without_openssl", "pq-src/with-openssl"]

DEVELOPMENT.md

@@ -0,0 +1,35 @@
+# DEVELOPMENT NOTES
+
+Use the following command to generate a new bindings file:
+```sh
+# keep the command in sync with the command in `src/make_bindings.rs"
+bindgen wrapper.h \
+    --rustified-enum ".*" \
+    --no-derive-default \
+    --generate "functions,types,vars,methods,constructors,destructors" \
+    --allowlist-var "PG_.*" \
+    --allowlist-var "LIBPQ_.*" \
+    --allowlist-var "PQ.*" \
+    --allowlist-type "Oid" \
+    --allowlist-type "ConnStatusType"  \
+    --allowlist-type "Postgres.*" \
+    --allowlist-type "pg.*" \
+    --allowlist-type "PG.*" \
+    --allowlist-type "PQ.*" \
+    --allowlist-type "pq.*" \
+    --allowlist-function "PQ.*" \
+    --allowlist-function "lo_.*" \
+    --allowlist-function "pg_.*" \
+    --opaque-type "FILE" \
+    --blocklist-type "FILE" \
+    --raw-line "use libc::FILE;" \
+    -- -I pq-src/source/src/interfaces/libpq/ -I pq-src/source/src/include/ -I pq-src/additional_include/
+```
+
+It is required to generate bindings for the following targets:
+
+* Linux 64 bit
+* Linux 32 bit (different field sizes, compilation fails otherwise due to const checks)
+* Windows (MSVC) 64 bit (uses `#[repr(i32)]` instead of `#[repr(u32)]` for enums,
+  can simply replace that in the generated linux bindings)
+* Windows (MSVC) 32 bit (same as 64 bit windows + 32 bit linux)

build.rs

@@ -90,20 +90,37 @@ fn main() {
         // by pq-src
         return;
     }
+    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap()).join("bindings.rs");
     #[cfg(feature = "buildtime_bindgen")]
     {
-        let bindings = bindgen::Builder::default()
-            .rustified_enum(".*")
-            .header("wrapper.h")
+        let bindings = include!("src/make_bindings.rs")
             .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
             .generate()
             .expect("Unable to generate bindings");
 
-        let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
         bindings
-            .write_to_file(out_path.join("bindings.rs"))
+            .write_to_file(out_path)
             .expect("Couldn't write bindings!");
     }
+    #[cfg(not(feature = "buildtime_bindgen"))]
+    {
+        let target_env = std::env::var("CARGO_CFG_TARGET_ENV").expect("Set by cargo");
+        let target_ptr_size =
+            std::env::var("CARGO_CFG_TARGET_POINTER_WIDTH").expect("Set by cargo");
+        let bindings_name = match (target_env.as_str(), target_ptr_size.as_str()) {
+            ("msvc", "32") => "src/bindings_windows_32.rs",
+            ("msvc", "64") => "src/bindings_windows.rs",
+            (_, "32") => "src/bindings_linux_32.rs",
+            (_, "64") => "src/bindings_linux.rs",
+            (target_env, ptr_width) => {
+                panic!("Unsupported target: TargetEnv: `{target_env}`, PtrWidth: `{ptr_width}`\n\
+                        If you use this target open an issue at https://github.com/sgrif/pq-sys/issues/new\
+                        outlining the details of this target");
+            }
+        };
+        let source_path = PathBuf::from(env!("CARGO_MANIFEST_DIR")).join(bindings_name);
+        std::fs::copy(source_path, out_path).expect("Couldn't write bindings");
+    }
 
     #[cfg(target_os = "windows")]
     println!("cargo:rustc-link-lib=libpq");